16 files changed, 19056 insertions, 0 deletions

diff --git a/kernel/sched/Makefile b/kernel/sched/Makefile
new file mode 100644
index 00000000000..9a7dd35102a
--- /dev/null
+++ b/kernel/sched/Makefile
@@ -0,0 +1,20 @@
+ifdef CONFIG_FUNCTION_TRACER
+CFLAGS_REMOVE_clock.o = -pg
+endif
+
+ifneq ($(CONFIG_SCHED_OMIT_FRAME_POINTER),y)
+# According to Alan Modra <alan@linuxcare.com.au>, the -fno-omit-frame-pointer is
+# needed for x86 only.  Why this used to be enabled for all architectures is beyond
+# me.  I suspect most platforms don't need this, but until we know that for sure
+# I turn this off for IA-64 only.  Andreas Schwab says it's also needed on m68k
+# to get a correct value for the wait-channel (WCHAN in ps). --davidm
+CFLAGS_core.o := $(PROFILING) -fno-omit-frame-pointer
+endif
+
+obj-y += core.o clock.o idle_task.o fair.o rt.o stop_task.o
+obj-$(CONFIG_SMP) += cpupri.o
+obj-$(CONFIG_SCHED_AUTOGROUP) += auto_group.o
+obj-$(CONFIG_SCHEDSTATS) += stats.o
+obj-$(CONFIG_SCHED_DEBUG) += debug.o
+
+
diff --git a/kernel/sched/auto_group.c b/kernel/sched/auto_group.c
new file mode 100644
index 00000000000..e8a1f83ee0e
--- /dev/null
+++ b/kernel/sched/auto_group.c
@@ -0,0 +1,258 @@
+#ifdef CONFIG_SCHED_AUTOGROUP
+
+#include "sched.h"
+
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/kallsyms.h>
+#include <linux/utsname.h>
+#include <linux/security.h>
+#include <linux/export.h>
+
+unsigned int __read_mostly sysctl_sched_autogroup_enabled = 1;
+static struct autogroup autogroup_default;
+static atomic_t autogroup_seq_nr;
+
+void __init autogroup_init(struct task_struct *init_task)
+{
+	autogroup_default.tg = &root_task_group;
+	kref_init(&autogroup_default.kref);
+	init_rwsem(&autogroup_default.lock);
+	init_task->signal->autogroup = &autogroup_default;
+}
+
+void autogroup_free(struct task_group *tg)
+{
+	kfree(tg->autogroup);
+}
+
+static inline void autogroup_destroy(struct kref *kref)
+{
+	struct autogroup *ag = container_of(kref, struct autogroup, kref);
+
+#ifdef CONFIG_RT_GROUP_SCHED
+	/* We've redirected RT tasks to the root task group... */
+	ag->tg->rt_se = NULL;
+	ag->tg->rt_rq = NULL;
+#endif
+	sched_destroy_group(ag->tg);
+}
+
+static inline void autogroup_kref_put(struct autogroup *ag)
+{
+	kref_put(&ag->kref, autogroup_destroy);
+}
+
+static inline struct autogroup *autogroup_kref_get(struct autogroup *ag)
+{
+	kref_get(&ag->kref);
+	return ag;
+}
+
+static inline struct autogroup *autogroup_task_get(struct task_struct *p)
+{
+	struct autogroup *ag;
+	unsigned long flags;
+
+	if (!lock_task_sighand(p, &flags))
+		return autogroup_kref_get(&autogroup_default);
+
+	ag = autogroup_kref_get(p->signal->autogroup);
+	unlock_task_sighand(p, &flags);
+
+	return ag;
+}
+
+static inline struct autogroup *autogroup_create(void)
+{
+	struct autogroup *ag = kzalloc(sizeof(*ag), GFP_KERNEL);
+	struct task_group *tg;
+
+	if (!ag)
+		goto out_fail;
+
+	tg = sched_create_group(&root_task_group);
+
+	if (IS_ERR(tg))
+		goto out_free;
+
+	kref_init(&ag->kref);
+	init_rwsem(&ag->lock);
+	ag->id = atomic_inc_return(&autogroup_seq_nr);
+	ag->tg = tg;
+#ifdef CONFIG_RT_GROUP_SCHED
+	/*
+	 * Autogroup RT tasks are redirected to the root task group
+	 * so we don't have to move tasks around upon policy change,
+	 * or flail around trying to allocate bandwidth on the fly.
+	 * A bandwidth exception in __sched_setscheduler() allows
+	 * the policy change to proceed.  Thereafter, task_group()
+	 * returns &root_task_group, so zero bandwidth is required.
+	 */
+	free_rt_sched_group(tg);
+	tg->rt_se = root_task_group.rt_se;
+	tg->rt_rq = root_task_group.rt_rq;
+#endif
+	tg->autogroup = ag;
+
+	return ag;
+
+out_free:
+	kfree(ag);
+out_fail:
+	if (printk_ratelimit()) {
+		printk(KERN_WARNING "autogroup_create: %s failure.\n",
+			ag ? "sched_create_group()" : "kmalloc()");
+	}
+
+	return autogroup_kref_get(&autogroup_default);
+}
+
+bool task_wants_autogroup(struct task_struct *p, struct task_group *tg)
+{
+	if (tg != &root_task_group)
+		return false;
+
+	if (p->sched_class != &fair_sched_class)
+		return false;
+
+	/*
+	 * We can only assume the task group can't go away on us if
+	 * autogroup_move_group() can see us on ->thread_group list.
+	 */
+	if (p->flags & PF_EXITING)
+		return false;
+
+	return true;
+}
+
+static void
+autogroup_move_group(struct task_struct *p, struct autogroup *ag)
+{
+	struct autogroup *prev;
+	struct task_struct *t;
+	unsigned long flags;
+
+	BUG_ON(!lock_task_sighand(p, &flags));
+
+	prev = p->signal->autogroup;
+	if (prev == ag) {
+		unlock_task_sighand(p, &flags);
+		return;
+	}
+
+	p->signal->autogroup = autogroup_kref_get(ag);
+
+	if (!ACCESS_ONCE(sysctl_sched_autogroup_enabled))
+		goto out;
+
+	t = p;
+	do {
+		sched_move_task(t);
+	} while_each_thread(p, t);
+
+out:
+	unlock_task_sighand(p, &flags);
+	autogroup_kref_put(prev);
+}
+
+/* Allocates GFP_KERNEL, cannot be called under any spinlock */
+void sched_autogroup_create_attach(struct task_struct *p)
+{
+	struct autogroup *ag = autogroup_create();
+
+	autogroup_move_group(p, ag);
+	/* drop extra reference added by autogroup_create() */
+	autogroup_kref_put(ag);
+}
+EXPORT_SYMBOL(sched_autogroup_create_attach);
+
+/* Cannot be called under siglock.  Currently has no users */
+void sched_autogroup_detach(struct task_struct *p)
+{
+	autogroup_move_group(p, &autogroup_default);
+}
+EXPORT_SYMBOL(sched_autogroup_detach);
+
+void sched_autogroup_fork(struct signal_struct *sig)
+{
+	sig->autogroup = autogroup_task_get(current);
+}
+
+void sched_autogroup_exit(struct signal_struct *sig)
+{
+	autogroup_kref_put(sig->autogroup);
+}
+
+static int __init setup_autogroup(char *str)
+{
+	sysctl_sched_autogroup_enabled = 0;
+
+	return 1;
+}
+
+__setup("noautogroup", setup_autogroup);
+
+#ifdef CONFIG_PROC_FS
+
+int proc_sched_autogroup_set_nice(struct task_struct *p, int *nice)
+{
+	static unsigned long next = INITIAL_JIFFIES;
+	struct autogroup *ag;
+	int err;
+
+	if (*nice < -20 || *nice > 19)
+		return -EINVAL;
+
+	err = security_task_setnice(current, *nice);
+	if (err)
+		return err;
+
+	if (*nice < 0 && !can_nice(current, *nice))
+		return -EPERM;
+
+	/* this is a heavy operation taking global locks.. */
+	if (!capable(CAP_SYS_ADMIN) && time_before(jiffies, next))
+		return -EAGAIN;
+
+	next = HZ / 10 + jiffies;
+	ag = autogroup_task_get(p);
+
+	down_write(&ag->lock);
+	err = sched_group_set_shares(ag->tg, prio_to_weight[*nice + 20]);
+	if (!err)
+		ag->nice = *nice;
+	up_write(&ag->lock);
+
+	autogroup_kref_put(ag);
+
+	return err;
+}
+
+void proc_sched_autogroup_show_task(struct task_struct *p, struct seq_file *m)
+{
+	struct autogroup *ag = autogroup_task_get(p);
+
+	if (!task_group_is_autogroup(ag->tg))
+		goto out;
+
+	down_read(&ag->lock);
+	seq_printf(m, "/autogroup-%ld nice %d\n", ag->id, ag->nice);
+	up_read(&ag->lock);
+
+out:
+	autogroup_kref_put(ag);
+}
+#endif /* CONFIG_PROC_FS */
+
+#ifdef CONFIG_SCHED_DEBUG
+int autogroup_path(struct task_group *tg, char *buf, int buflen)
+{
+	if (!task_group_is_autogroup(tg))
+		return 0;
+
+	return snprintf(buf, buflen, "%s-%ld", "/autogroup", tg->autogroup->id);
+}
+#endif /* CONFIG_SCHED_DEBUG */
+
+#endif /* CONFIG_SCHED_AUTOGROUP */
diff --git a/kernel/sched/auto_group.h b/kernel/sched/auto_group.h
new file mode 100644
index 00000000000..8bd04714281
--- /dev/null
+++ b/kernel/sched/auto_group.h
@@ -0,0 +1,64 @@
+#ifdef CONFIG_SCHED_AUTOGROUP
+
+#include <linux/kref.h>
+#include <linux/rwsem.h>
+
+struct autogroup {
+	/*
+	 * reference doesn't mean how many thread attach to this
+	 * autogroup now. It just stands for the number of task
+	 * could use this autogroup.
+	 */
+	struct kref		kref;
+	struct task_group	*tg;
+	struct rw_semaphore	lock;
+	unsigned long		id;
+	int			nice;
+};
+
+extern void autogroup_init(struct task_struct *init_task);
+extern void autogroup_free(struct task_group *tg);
+
+static inline bool task_group_is_autogroup(struct task_group *tg)
+{
+	return !!tg->autogroup;
+}
+
+extern bool task_wants_autogroup(struct task_struct *p, struct task_group *tg);
+
+static inline struct task_group *
+autogroup_task_group(struct task_struct *p, struct task_group *tg)
+{
+	int enabled = ACCESS_ONCE(sysctl_sched_autogroup_enabled);
+
+	if (enabled && task_wants_autogroup(p, tg))
+		return p->signal->autogroup->tg;
+
+	return tg;
+}
+
+extern int autogroup_path(struct task_group *tg, char *buf, int buflen);
+
+#else /* !CONFIG_SCHED_AUTOGROUP */
+
+static inline void autogroup_init(struct task_struct *init_task) {  }
+static inline void autogroup_free(struct task_group *tg) { }
+static inline bool task_group_is_autogroup(struct task_group *tg)
+{
+	return 0;
+}
+
+static inline struct task_group *
+autogroup_task_group(struct task_struct *p, struct task_group *tg)
+{
+	return tg;
+}
+
+#ifdef CONFIG_SCHED_DEBUG
+static inline int autogroup_path(struct task_group *tg, char *buf, int buflen)
+{
+	return 0;
+}
+#endif
+
+#endif /* CONFIG_SCHED_AUTOGROUP */
diff --git a/kernel/sched/clock.c b/kernel/sched/clock.c
new file mode 100644
index 00000000000..c685e31492d
--- /dev/null
+++ b/kernel/sched/clock.c
@@ -0,0 +1,350 @@
+/*
+ * sched_clock for unstable cpu clocks
+ *
+ *  Copyright (C) 2008 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
+ *
+ *  Updates and enhancements:
+ *    Copyright (C) 2008 Red Hat, Inc. Steven Rostedt <srostedt@redhat.com>
+ *
+ * Based on code by:
+ *   Ingo Molnar <mingo@redhat.com>
+ *   Guillaume Chazarain <guichaz@gmail.com>
+ *
+ *
+ * What:
+ *
+ * cpu_clock(i) provides a fast (execution time) high resolution
+ * clock with bounded drift between CPUs. The value of cpu_clock(i)
+ * is monotonic for constant i. The timestamp returned is in nanoseconds.
+ *
+ * ######################### BIG FAT WARNING ##########################
+ * # when comparing cpu_clock(i) to cpu_clock(j) for i != j, time can #
+ * # go backwards !!                                                  #
+ * ####################################################################
+ *
+ * There is no strict promise about the base, although it tends to start
+ * at 0 on boot (but people really shouldn't rely on that).
+ *
+ * cpu_clock(i)       -- can be used from any context, including NMI.
+ * sched_clock_cpu(i) -- must be used with local IRQs disabled (implied by NMI)
+ * local_clock()      -- is cpu_clock() on the current cpu.
+ *
+ * How:
+ *
+ * The implementation either uses sched_clock() when
+ * !CONFIG_HAVE_UNSTABLE_SCHED_CLOCK, which means in that case the
+ * sched_clock() is assumed to provide these properties (mostly it means
+ * the architecture provides a globally synchronized highres time source).
+ *
+ * Otherwise it tries to create a semi stable clock from a mixture of other
+ * clocks, including:
+ *
+ *  - GTOD (clock monotomic)
+ *  - sched_clock()
+ *  - explicit idle events
+ *
+ * We use GTOD as base and use sched_clock() deltas to improve resolution. The
+ * deltas are filtered to provide monotonicity and keeping it within an
+ * expected window.
+ *
+ * Furthermore, explicit sleep and wakeup hooks allow us to account for time
+ * that is otherwise invisible (TSC gets stopped).
+ *
+ *
+ * Notes:
+ *
+ * The !IRQ-safetly of sched_clock() and sched_clock_cpu() comes from things
+ * like cpufreq interrupts that can change the base clock (TSC) multiplier
+ * and cause funny jumps in time -- although the filtering provided by
+ * sched_clock_cpu() should mitigate serious artifacts we cannot rely on it
+ * in general since for !CONFIG_HAVE_UNSTABLE_SCHED_CLOCK we fully rely on
+ * sched_clock().
+ */
+#include <linux/spinlock.h>
+#include <linux/hardirq.h>
+#include <linux/export.h>
+#include <linux/percpu.h>
+#include <linux/ktime.h>
+#include <linux/sched.h>
+
+/*
+ * Scheduler clock - returns current time in nanosec units.
+ * This is default implementation.
+ * Architectures and sub-architectures can override this.
+ */
+unsigned long long __attribute__((weak)) sched_clock(void)
+{
+	return (unsigned long long)(jiffies - INITIAL_JIFFIES)
+					* (NSEC_PER_SEC / HZ);
+}
+EXPORT_SYMBOL_GPL(sched_clock);
+
+__read_mostly int sched_clock_running;
+
+#ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
+__read_mostly int sched_clock_stable;
+
+struct sched_clock_data {
+	u64			tick_raw;
+	u64			tick_gtod;
+	u64			clock;
+};
+
+static DEFINE_PER_CPU_SHARED_ALIGNED(struct sched_clock_data, sched_clock_data);
+
+static inline struct sched_clock_data *this_scd(void)
+{
+	return &__get_cpu_var(sched_clock_data);
+}
+
+static inline struct sched_clock_data *cpu_sdc(int cpu)
+{
+	return &per_cpu(sched_clock_data, cpu);
+}
+
+void sched_clock_init(void)
+{
+	u64 ktime_now = ktime_to_ns(ktime_get());
+	int cpu;
+
+	for_each_possible_cpu(cpu) {
+		struct sched_clock_data *scd = cpu_sdc(cpu);
+
+		scd->tick_raw = 0;
+		scd->tick_gtod = ktime_now;
+		scd->clock = ktime_now;
+	}
+
+	sched_clock_running = 1;
+}
+
+/*
+ * min, max except they take wrapping into account
+ */
+
+static inline u64 wrap_min(u64 x, u64 y)
+{
+	return (s64)(x - y) < 0 ? x : y;
+}
+
+static inline u64 wrap_max(u64 x, u64 y)
+{
+	return (s64)(x - y) > 0 ? x : y;
+}
+
+/*
+ * update the percpu scd from the raw @now value
+ *
+ *  - filter out backward motion
+ *  - use the GTOD tick value to create a window to filter crazy TSC values
+ */
+static u64 sched_clock_local(struct sched_clock_data *scd)
+{
+	u64 now, clock, old_clock, min_clock, max_clock;
+	s64 delta;
+
+again:
+	now = sched_clock();
+	delta = now - scd->tick_raw;
+	if (unlikely(delta < 0))
+		delta = 0;
+
+	old_clock = scd->clock;
+
+	/*
+	 * scd->clock = clamp(scd->tick_gtod + delta,
+	 *		      max(scd->tick_gtod, scd->clock),
+	 *		      scd->tick_gtod + TICK_NSEC);
+	 */
+
+	clock = scd->tick_gtod + delta;
+	min_clock = wrap_max(scd->tick_gtod, old_clock);
+	max_clock = wrap_max(old_clock, scd->tick_gtod + TICK_NSEC);
+
+	clock = wrap_max(clock, min_clock);
+	clock = wrap_min(clock, max_clock);
+
+	if (cmpxchg64(&scd->clock, old_clock, clock) != old_clock)
+		goto again;
+
+	return clock;
+}
+
+static u64 sched_clock_remote(struct sched_clock_data *scd)
+{
+	struct sched_clock_data *my_scd = this_scd();
+	u64 this_clock, remote_clock;
+	u64 *ptr, old_val, val;
+
+	sched_clock_local(my_scd);
+again:
+	this_clock = my_scd->clock;
+	remote_clock = scd->clock;
+
+	/*
+	 * Use the opportunity that we have both locks
+	 * taken to couple the two clocks: we take the
+	 * larger time as the latest time for both
+	 * runqueues. (this creates monotonic movement)
+	 */
+	if (likely((s64)(remote_clock - this_clock) < 0)) {
+		ptr = &scd->clock;
+		old_val = remote_clock;
+		val = this_clock;
+	} else {
+		/*
+		 * Should be rare, but possible:
+		 */
+		ptr = &my_scd->clock;
+		old_val = this_clock;
+		val = remote_clock;
+	}
+
+	if (cmpxchg64(ptr, old_val, val) != old_val)
+		goto again;
+
+	return val;
+}
+
+/*
+ * Similar to cpu_clock(), but requires local IRQs to be disabled.
+ *
+ * See cpu_clock().
+ */
+u64 sched_clock_cpu(int cpu)
+{
+	struct sched_clock_data *scd;
+	u64 clock;
+
+	WARN_ON_ONCE(!irqs_disabled());
+
+	if (sched_clock_stable)
+		return sched_clock();
+
+	if (unlikely(!sched_clock_running))
+		return 0ull;
+
+	scd = cpu_sdc(cpu);
+
+	if (cpu != smp_processor_id())
+		clock = sched_clock_remote(scd);
+	else
+		clock = sched_clock_local(scd);
+
+	return clock;
+}
+
+void sched_clock_tick(void)
+{
+	struct sched_clock_data *scd;
+	u64 now, now_gtod;
+
+	if (sched_clock_stable)
+		return;
+
+	if (unlikely(!sched_clock_running))
+		return;
+
+	WARN_ON_ONCE(!irqs_disabled());
+
+	scd = this_scd();
+	now_gtod = ktime_to_ns(ktime_get());
+	now = sched_clock();
+
+	scd->tick_raw = now;
+	scd->tick_gtod = now_gtod;
+	sched_clock_local(scd);
+}
+
+/*
+ * We are going deep-idle (irqs are disabled):
+ */
+void sched_clock_idle_sleep_event(void)
+{
+	sched_clock_cpu(smp_processor_id());
+}
+EXPORT_SYMBOL_GPL(sched_clock_idle_sleep_event);
+
+/*
+ * We just idled delta nanoseconds (called with irqs disabled):
+ */
+void sched_clock_idle_wakeup_event(u64 delta_ns)
+{
+	if (timekeeping_suspended)
+		return;
+
+	sched_clock_tick();
+	touch_softlockup_watchdog();
+}
+EXPORT_SYMBOL_GPL(sched_clock_idle_wakeup_event);
+
+/*
+ * As outlined at the top, provides a fast, high resolution, nanosecond
+ * time source that is monotonic per cpu argument and has bounded drift
+ * between cpus.
+ *
+ * ######################### BIG FAT WARNING ##########################
+ * # when comparing cpu_clock(i) to cpu_clock(j) for i != j, time can #
+ * # go backwards !!                                                  #
+ * ####################################################################
+ */
+u64 cpu_clock(int cpu)
+{
+	u64 clock;
+	unsigned long flags;
+
+	local_irq_save(flags);
+	clock = sched_clock_cpu(cpu);
+	local_irq_restore(flags);
+
+	return clock;
+}
+
+/*
+ * Similar to cpu_clock() for the current cpu. Time will only be observed
+ * to be monotonic if care is taken to only compare timestampt taken on the
+ * same CPU.
+ *
+ * See cpu_clock().
+ */
+u64 local_clock(void)
+{
+	u64 clock;
+	unsigned long flags;
+
+	local_irq_save(flags);
+	clock = sched_clock_cpu(smp_processor_id());
+	local_irq_restore(flags);
+
+	return clock;
+}
+
+#else /* CONFIG_HAVE_UNSTABLE_SCHED_CLOCK */
+
+void sched_clock_init(void)
+{
+	sched_clock_running = 1;
+}
+
+u64 sched_clock_cpu(int cpu)
+{
+	if (unlikely(!sched_clock_running))
+		return 0;
+
+	return sched_clock();
+}
+
+u64 cpu_clock(int cpu)
+{
+	return sched_clock_cpu(cpu);
+}
+
+u64 local_clock(void)
+{
+	return sched_clock_cpu(0);
+}
+
+#endif /* CONFIG_HAVE_UNSTABLE_SCHED_CLOCK */
+
+EXPORT_SYMBOL_GPL(cpu_clock);
+EXPORT_SYMBOL_GPL(local_clock);
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
new file mode 100644
index 00000000000..df00cb09263
--- /dev/null
+++ b/kernel/sched/core.c
@@ -0,0 +1,8150 @@
+/*
+ *  kernel/sched/core.c
+ *
+ *  Kernel scheduler and related syscalls
+ *
+ *  Copyright (C) 1991-2002  Linus Torvalds
+ *
+ *  1996-12-23  Modified by Dave Grothe to fix bugs in semaphores and
+ *		make semaphores SMP safe
+ *  1998-11-19	Implemented schedule_timeout() and related stuff
+ *		by Andrea Arcangeli
+ *  2002-01-04	New ultra-scalable O(1) scheduler by Ingo Molnar:
+ *		hybrid priority-list and round-robin design with
+ *		an array-switch method of distributing timeslices
+ *		and per-CPU runqueues.  Cleanups and useful suggestions
+ *		by Davide Libenzi, preemptible kernel bits by Robert Love.
+ *  2003-09-03	Interactivity tuning by Con Kolivas.
+ *  2004-04-02	Scheduler domains code by Nick Piggin
+ *  2007-04-15  Work begun on replacing all interactivity tuning with a
+ *              fair scheduling design by Con Kolivas.
+ *  2007-05-05  Load balancing (smp-nice) and other improvements
+ *              by Peter Williams
+ *  2007-05-06  Interactivity improvements to CFS by Mike Galbraith
+ *  2007-07-01  Group scheduling enhancements by Srivatsa Vaddagiri
+ *  2007-11-29  RT balancing improvements by Steven Rostedt, Gregory Haskins,
+ *              Thomas Gleixner, Mike Kravetz
+ */
+
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/nmi.h>
+#include <linux/init.h>
+#include <linux/uaccess.h>
+#include <linux/highmem.h>
+#include <asm/mmu_context.h>
+#include <linux/interrupt.h>
+#include <linux/capability.h>
+#include <linux/completion.h>
+#include <linux/kernel_stat.h>
+#include <linux/debug_locks.h>
+#include <linux/perf_event.h>
+#include <linux/security.h>
+#include <linux/notifier.h>
+#include <linux/profile.h>
+#include <linux/freezer.h>
+#include <linux/vmalloc.h>
+#include <linux/blkdev.h>
+#include <linux/delay.h>
+#include <linux/pid_namespace.h>
+#include <linux/smp.h>
+#include <linux/threads.h>
+#include <linux/timer.h>
+#include <linux/rcupdate.h>
+#include <linux/cpu.h>
+#include <linux/cpuset.h>
+#include <linux/percpu.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/sysctl.h>
+#include <linux/syscalls.h>
+#include <linux/times.h>
+#include <linux/tsacct_kern.h>
+#include <linux/kprobes.h>
+#include <linux/delayacct.h>
+#include <linux/unistd.h>
+#include <linux/pagemap.h>
+#include <linux/hrtimer.h>
+#include <linux/tick.h>
+#include <linux/debugfs.h>
+#include <linux/ctype.h>
+#include <linux/ftrace.h>
+#include <linux/slab.h>
+#include <linux/init_task.h>
+
+#include <asm/tlb.h>
+#include <asm/irq_regs.h>
+#ifdef CONFIG_PARAVIRT
+#include <asm/paravirt.h>
+#endif
+
+#include "sched.h"
+#include "../workqueue_sched.h"
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/sched.h>
+
+void start_bandwidth_timer(struct hrtimer *period_timer, ktime_t period)
+{
+	unsigned long delta;
+	ktime_t soft, hard, now;
+
+	for (;;) {
+		if (hrtimer_active(period_timer))
+			break;
+
+		now = hrtimer_cb_get_time(period_timer);
+		hrtimer_forward(period_timer, now, period);
+
+		soft = hrtimer_get_softexpires(period_timer);
+		hard = hrtimer_get_expires(period_timer);
+		delta = ktime_to_ns(ktime_sub(hard, soft));
+		__hrtimer_start_range_ns(period_timer, soft, delta,
+					 HRTIMER_MODE_ABS_PINNED, 0);
+	}
+}
+
+DEFINE_MUTEX(sched_domains_mutex);
+DEFINE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
+
+static void update_rq_clock_task(struct rq *rq, s64 delta);
+
+void update_rq_clock(struct rq *rq)
+{
+	s64 delta;
+
+	if (rq->skip_clock_update > 0)
+		return;
+
+	delta = sched_clock_cpu(cpu_of(rq)) - rq->clock;
+	rq->clock += delta;
+	update_rq_clock_task(rq, delta);
+}
+
+/*
+ * Debugging: various feature bits
+ */
+
+#define SCHED_FEAT(name, enabled)	\
+	(1UL << __SCHED_FEAT_##name) * enabled |
+
+const_debug unsigned int sysctl_sched_features =
+#include "features.h"
+	0;
+
+#undef SCHED_FEAT
+
+#ifdef CONFIG_SCHED_DEBUG
+#define SCHED_FEAT(name, enabled)	\
+	#name ,
+
+static __read_mostly char *sched_feat_names[] = {
+#include "features.h"
+	NULL
+};
+
+#undef SCHED_FEAT
+
+static int sched_feat_show(struct seq_file *m, void *v)
+{
+	int i;
+
+	for (i = 0; i < __SCHED_FEAT_NR; i++) {
+		if (!(sysctl_sched_features & (1UL << i)))
+			seq_puts(m, "NO_");
+		seq_printf(m, "%s ", sched_feat_names[i]);
+	}
+	seq_puts(m, "\n");
+
+	return 0;
+}
+
+#ifdef HAVE_JUMP_LABEL
+
+#define jump_label_key__true  jump_label_key_enabled
+#define jump_label_key__false jump_label_key_disabled
+
+#define SCHED_FEAT(name, enabled)	\
+	jump_label_key__##enabled ,
+
+struct jump_label_key sched_feat_keys[__SCHED_FEAT_NR] = {
+#include "features.h"
+};
+
+#undef SCHED_FEAT
+
+static void sched_feat_disable(int i)
+{
+	if (jump_label_enabled(&sched_feat_keys[i]))
+		jump_label_dec(&sched_feat_keys[i]);
+}
+
+static void sched_feat_enable(int i)
+{
+	if (!jump_label_enabled(&sched_feat_keys[i]))
+		jump_label_inc(&sched_feat_keys[i]);
+}
+#else
+static void sched_feat_disable(int i) { };
+static void sched_feat_enable(int i) { };
+#endif /* HAVE_JUMP_LABEL */
+
+static ssize_t
+sched_feat_write(struct file *filp, const char __user *ubuf,
+		size_t cnt, loff_t *ppos)
+{
+	char buf[64];
+	char *cmp;
+	int neg = 0;
+	int i;
+
+	if (cnt > 63)
+		cnt = 63;
+
+	if (copy_from_user(&buf, ubuf, cnt))
+		return -EFAULT;
+
+	buf[cnt] = 0;
+	cmp = strstrip(buf);
+
+	if (strncmp(cmp, "NO_", 3) == 0) {
+		neg = 1;
+		cmp += 3;
+	}
+
+	for (i = 0; i < __SCHED_FEAT_NR; i++) {
+		if (strcmp(cmp, sched_feat_names[i]) == 0) {
+			if (neg) {
+				sysctl_sched_features &= ~(1UL << i);
+				sched_feat_disable(i);
+			} else {
+				sysctl_sched_features |= (1UL << i);
+				sched_feat_enable(i);
+			}
+			break;
+		}
+	}
+
+	if (i == __SCHED_FEAT_NR)
+		return -EINVAL;
+
+	*ppos += cnt;
+
+	return cnt;
+}
+
+static int sched_feat_open(struct inode *inode, struct file *filp)
+{
+	return single_open(filp, sched_feat_show, NULL);
+}
+
+static const struct file_operations sched_feat_fops = {
+	.open		= sched_feat_open,
+	.write		= sched_feat_write,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+static __init int sched_init_debug(void)
+{
+	debugfs_create_file("sched_features", 0644, NULL, NULL,
+			&sched_feat_fops);
+
+	return 0;
+}
+late_initcall(sched_init_debug);
+#endif /* CONFIG_SCHED_DEBUG */
+
+/*
+ * Number of tasks to iterate in a single balance run.
+ * Limited because this is done with IRQs disabled.
+ */
+const_debug unsigned int sysctl_sched_nr_migrate = 32;
+
+/*
+ * period over which we average the RT time consumption, measured
+ * in ms.
+ *
+ * default: 1s
+ */
+const_debug unsigned int sysctl_sched_time_avg = MSEC_PER_SEC;
+
+/*
+ * period over which we measure -rt task cpu usage in us.
+ * default: 1s
+ */
+unsigned int sysctl_sched_rt_period = 1000000;
+
+__read_mostly int scheduler_running;
+
+/*
+ * part of the period that we allow rt tasks to run in us.
+ * default: 0.95s
+ */
+int sysctl_sched_rt_runtime = 950000;
+
+
+
+/*
+ * __task_rq_lock - lock the rq @p resides on.
+ */
+static inline struct rq *__task_rq_lock(struct task_struct *p)
+	__acquires(rq->lock)
+{
+	struct rq *rq;
+
+	lockdep_assert_held(&p->pi_lock);
+
+	for (;;) {
+		rq = task_rq(p);
+		raw_spin_lock(&rq->lock);
+		if (likely(rq == task_rq(p)))
+			return rq;
+		raw_spin_unlock(&rq->lock);
+	}
+}
+
+/*
+ * task_rq_lock - lock p->pi_lock and lock the rq @p resides on.
+ */
+static struct rq *task_rq_lock(struct task_struct *p, unsigned long *flags)
+	__acquires(p->pi_lock)
+	__acquires(rq->lock)
+{
+	struct rq *rq;
+
+	for (;;) {
+		raw_spin_lock_irqsave(&p->pi_lock, *flags);
+		rq = task_rq(p);
+		raw_spin_lock(&rq->lock);
+		if (likely(rq == task_rq(p)))
+			return rq;
+		raw_spin_unlock(&rq->lock);
+		raw_spin_unlock_irqrestore(&p->pi_lock, *flags);
+	}
+}
+
+static void __task_rq_unlock(struct rq *rq)
+	__releases(rq->lock)
+{
+	raw_spin_unlock(&rq->lock);
+}
+
+static inline void
+task_rq_unlock(struct rq *rq, struct task_struct *p, unsigned long *flags)
+	__releases(rq->lock)
+	__releases(p->pi_lock)
+{
+	raw_spin_unlock(&rq->lock);
+	raw_spin_unlock_irqrestore(&p->pi_lock, *flags);
+}
+
+/*
+ * this_rq_lock - lock this runqueue and disable interrupts.
+ */
+static struct rq *this_rq_lock(void)
+	__acquires(rq->lock)
+{
+	struct rq *rq;
+
+	local_irq_disable();
+	rq = this_rq();
+	raw_spin_lock(&rq->lock);
+
+	return rq;
+}
+
+#ifdef CONFIG_SCHED_HRTICK
+/*
+ * Use HR-timers to deliver accurate preemption points.
+ *
+ * Its all a bit involved since we cannot program an hrt while holding the
+ * rq->lock. So what we do is store a state in in rq->hrtick_* and ask for a
+ * reschedule event.
+ *
+ * When we get rescheduled we reprogram the hrtick_timer outside of the
+ * rq->lock.
+ */
+
+static void hrtick_clear(struct rq *rq)
+{
+	if (hrtimer_active(&rq->hrtick_timer))
+		hrtimer_cancel(&rq->hrtick_timer);
+}
+
+/*
+ * High-resolution timer tick.
+ * Runs from hardirq context with interrupts disabled.
+ */
+static enum hrtimer_restart hrtick(struct hrtimer *timer)
+{
+	struct rq *rq = container_of(timer, struct rq, hrtick_timer);
+
+	WARN_ON_ONCE(cpu_of(rq) != smp_processor_id());
+
+	raw_spin_lock(&rq->lock);
+	update_rq_clock(rq);
+	rq->curr->sched_class->task_tick(rq, rq->curr, 1);
+	raw_spin_unlock(&rq->lock);
+
+	return HRTIMER_NORESTART;
+}
+
+#ifdef CONFIG_SMP
+/*
+ * called from hardirq (IPI) context
+ */
+static void __hrtick_start(void *arg)
+{
+	struct rq *rq = arg;
+
+	raw_spin_lock(&rq->lock);
+	hrtimer_restart(&rq->hrtick_timer);
+	rq->hrtick_csd_pending = 0;
+	raw_spin_unlock(&rq->lock);
+}
+
+/*
+ * Called to set the hrtick timer state.
+ *
+ * called with rq->lock held and irqs disabled
+ */
+void hrtick_start(struct rq *rq, u64 delay)
+{
+	struct hrtimer *timer = &rq->hrtick_timer;
+	ktime_t time = ktime_add_ns(timer->base->get_time(), delay);
+
+	hrtimer_set_expires(timer, time);
+
+	if (rq == this_rq()) {
+		hrtimer_restart(timer);
+	} else if (!rq->hrtick_csd_pending) {
+		__smp_call_function_single(cpu_of(rq), &rq->hrtick_csd, 0);
+		rq->hrtick_csd_pending = 1;
+	}
+}
+
+static int
+hotplug_hrtick(struct notifier_block *nfb, unsigned long action, void *hcpu)
+{
+	int cpu = (int)(long)hcpu;
+
+	switch (action) {
+	case CPU_UP_CANCELED:
+	case CPU_UP_CANCELED_FROZEN:
+	case CPU_DOWN_PREPARE:
+	case CPU_DOWN_PREPARE_FROZEN:
+	case CPU_DEAD:
+	case CPU_DEAD_FROZEN:
+		hrtick_clear(cpu_rq(cpu));
+		return NOTIFY_OK;
+	}
+
+	return NOTIFY_DONE;
+}
+
+static __init void init_hrtick(void)
+{
+	hotcpu_notifier(hotplug_hrtick, 0);
+}
+#else
+/*
+ * Called to set the hrtick timer state.
+ *
+ * called with rq->lock held and irqs disabled
+ */
+void hrtick_start(struct rq *rq, u64 delay)
+{
+	__hrtimer_start_range_ns(&rq->hrtick_timer, ns_to_ktime(delay), 0,
+			HRTIMER_MODE_REL_PINNED, 0);
+}
+
+static inline void init_hrtick(void)
+{
+}
+#endif /* CONFIG_SMP */
+
+static void init_rq_hrtick(struct rq *rq)
+{
+#ifdef CONFIG_SMP
+	rq->hrtick_csd_pending = 0;
+
+	rq->hrtick_csd.flags = 0;
+	rq->hrtick_csd.func = __hrtick_start;
+	rq->hrtick_csd.info = rq;
+#endif
+
+	hrtimer_init(&rq->hrtick_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	rq->hrtick_timer.function = hrtick;
+}
+#else	/* CONFIG_SCHED_HRTICK */
+static inline void hrtick_clear(struct rq *rq)
+{
+}
+
+static inline void init_rq_hrtick(struct rq *rq)
+{
+}
+
+static inline void init_hrtick(void)
+{
+}
+#endif	/* CONFIG_SCHED_HRTICK */
+
+/*
+ * resched_task - mark a task 'to be rescheduled now'.
+ *
+ * On UP this means the setting of the need_resched flag, on SMP it
+ * might also involve a cross-CPU call to trigger the scheduler on
+ * the target CPU.
+ */
+#ifdef CONFIG_SMP
+
+#ifndef tsk_is_polling
+#define tsk_is_polling(t) test_tsk_thread_flag(t, TIF_POLLING_NRFLAG)
+#endif
+
+void resched_task(struct task_struct *p)
+{
+	int cpu;
+
+	assert_raw_spin_locked(&task_rq(p)->lock);
+
+	if (test_tsk_need_resched(p))
+		return;
+
+	set_tsk_need_resched(p);
+
+	cpu = task_cpu(p);
+	if (cpu == smp_processor_id())
+		return;
+
+	/* NEED_RESCHED must be visible before we test polling */
+	smp_mb();
+	if (!tsk_is_polling(p))
+		smp_send_reschedule(cpu);
+}
+
+void resched_cpu(int cpu)
+{
+	struct rq *rq = cpu_rq(cpu);
+	unsigned long flags;
+
+	if (!raw_spin_trylock_irqsave(&rq->lock, flags))
+		return;
+	resched_task(cpu_curr(cpu));
+	raw_spin_unlock_irqrestore(&rq->lock, flags);
+}
+
+#ifdef CONFIG_NO_HZ
+/*
+ * In the semi idle case, use the nearest busy cpu for migrating timers
+ * from an idle cpu.  This is good for power-savings.
+ *
+ * We don't do similar optimization for completely idle system, as
+ * selecting an idle cpu will add more delays to the timers than intended
+ * (as that cpu's timer base may not be uptodate wrt jiffies etc).
+ */
+int get_nohz_timer_target(void)
+{
+	int cpu = smp_processor_id();
+	int i;
+	struct sched_domain *sd;
+
+	rcu_read_lock();
+	for_each_domain(cpu, sd) {
+		for_each_cpu(i, sched_domain_span(sd)) {
+			if (!idle_cpu(i)) {
+				cpu = i;
+				goto unlock;
+			}
+		}
+	}
+unlock:
+	rcu_read_unlock();
+	return cpu;
+}
+/*
+ * When add_timer_on() enqueues a timer into the timer wheel of an
+ * idle CPU then this timer might expire before the next timer event
+ * which is scheduled to wake up that CPU. In case of a completely
+ * idle system the next event might even be infinite time into the
+ * future. wake_up_idle_cpu() ensures that the CPU is woken up and
+ * leaves the inner idle loop so the newly added timer is taken into
+ * account when the CPU goes back to idle and evaluates the timer
+ * wheel for the next timer event.
+ */
+void wake_up_idle_cpu(int cpu)
+{
+	struct rq *rq = cpu_rq(cpu);
+
+	if (cpu == smp_processor_id())
+		return;
+
+	/*
+	 * This is safe, as this function is called with the timer
+	 * wheel base lock of (cpu) held. When the CPU is on the way
+	 * to idle and has not yet set rq->curr to idle then it will
+	 * be serialized on the timer wheel base lock and take the new
+	 * timer into account automatically.
+	 */
+	if (rq->curr != rq->idle)
+		return;
+
+	/*
+	 * We can set TIF_RESCHED on the idle task of the other CPU
+	 * lockless. The worst case is that the other CPU runs the
+	 * idle task through an additional NOOP schedule()
+	 */
+	set_tsk_need_resched(rq->idle);
+
+	/* NEED_RESCHED must be visible before we test polling */
+	smp_mb();
+	if (!tsk_is_polling(rq->idle))
+		smp_send_reschedule(cpu);
+}
+
+static inline bool got_nohz_idle_kick(void)
+{
+	int cpu = smp_processor_id();
+	return idle_cpu(cpu) && test_bit(NOHZ_BALANCE_KICK, nohz_flags(cpu));
+}
+
+#else /* CONFIG_NO_HZ */
+
+static inline bool got_nohz_idle_kick(void)
+{
+	return false;
+}
+
+#endif /* CONFIG_NO_HZ */
+
+void sched_avg_update(struct rq *rq)
+{
+	s64 period = sched_avg_period();
+
+	while ((s64)(rq->clock - rq->age_stamp) > period) {
+		/*
+		 * Inline assembly required to prevent the compiler
+		 * optimising this loop into a divmod call.
+		 * See __iter_div_u64_rem() for another example of this.
+		 */
+		asm("" : "+rm" (rq->age_stamp));
+		rq->age_stamp += period;
+		rq->rt_avg /= 2;
+	}
+}
+
+#else /* !CONFIG_SMP */
+void resched_task(struct task_struct *p)
+{
+	assert_raw_spin_locked(&task_rq(p)->lock);
+	set_tsk_need_resched(p);
+}
+#endif /* CONFIG_SMP */
+
+#if defined(CONFIG_RT_GROUP_SCHED) || (defined(CONFIG_FAIR_GROUP_SCHED) && \
+			(defined(CONFIG_SMP) || defined(CONFIG_CFS_BANDWIDTH)))
+/*
+ * Iterate task_group tree rooted at *from, calling @down when first entering a
+ * node and @up when leaving it for the final time.
+ *
+ * Caller must hold rcu_lock or sufficient equivalent.
+ */
+int walk_tg_tree_from(struct task_group *from,
+			     tg_visitor down, tg_visitor up, void *data)
+{
+	struct task_group *parent, *child;
+	int ret;
+
+	parent = from;
+
+down:
+	ret = (*down)(parent, data);
+	if (ret)
+		goto out;
+	list_for_each_entry_rcu(child, &parent->children, siblings) {
+		parent = child;
+		goto down;
+
+up:
+		continue;
+	}
+	ret = (*up)(parent, data);
+	if (ret || parent == from)
+		goto out;
+
+	child = parent;
+	parent = parent->parent;
+	if (parent)
+		goto up;
+out:
+	return ret;
+}
+
+int tg_nop(struct task_group *tg, void *data)
+{
+	return 0;
+}
+#endif
+
+void update_cpu_load(struct rq *this_rq);
+
+static void set_load_weight(struct task_struct *p)
+{
+	int prio = p->static_prio - MAX_RT_PRIO;
+	struct load_weight *load = &p->se.load;
+
+	/*
+	 * SCHED_IDLE tasks get minimal weight:
+	 */
+	if (p->policy == SCHED_IDLE) {
+		load->weight = scale_load(WEIGHT_IDLEPRIO);
+		load->inv_weight = WMULT_IDLEPRIO;
+		return;
+	}
+
+	load->weight = scale_load(prio_to_weight[prio]);
+	load->inv_weight = prio_to_wmult[prio];
+}
+
+static void enqueue_task(struct rq *rq, struct task_struct *p, int flags)
+{
+	update_rq_clock(rq);
+	sched_info_queued(p);
+	p->sched_class->enqueue_task(rq, p, flags);
+}
+
+static void dequeue_task(struct rq *rq, struct task_struct *p, int flags)
+{
+	update_rq_clock(rq);
+	sched_info_dequeued(p);
+	p->sched_class->dequeue_task(rq, p, flags);
+}
+
+/*
+ * activate_task - move a task to the runqueue.
+ */
+void activate_task(struct rq *rq, struct task_struct *p, int flags)
+{
+	if (task_contributes_to_load(p))
+		rq->nr_uninterruptible--;
+
+	enqueue_task(rq, p, flags);
+}
+
+/*
+ * deactivate_task - remove a task from the runqueue.
+ */
+void deactivate_task(struct rq *rq, struct task_struct *p, int flags)
+{
+	if (task_contributes_to_load(p))
+		rq->nr_uninterruptible++;
+
+	dequeue_task(rq, p, flags);
+}
+
+#ifdef CONFIG_IRQ_TIME_ACCOUNTING
+
+/*
+ * There are no locks covering percpu hardirq/softirq time.
+ * They are only modified in account_system_vtime, on corresponding CPU
+ * with interrupts disabled. So, writes are safe.
+ * They are read and saved off onto struct rq in update_rq_clock().
+ * This may result in other CPU reading this CPU's irq time and can
+ * race with irq/account_system_vtime on this CPU. We would either get old
+ * or new value with a side effect of accounting a slice of irq time to wrong
+ * task when irq is in progress while we read rq->clock. That is a worthy
+ * compromise in place of having locks on each irq in account_system_time.
+ */
+static DEFINE_PER_CPU(u64, cpu_hardirq_time);
+static DEFINE_PER_CPU(u64, cpu_softirq_time);
+
+static DEFINE_PER_CPU(u64, irq_start_time);
+static int sched_clock_irqtime;
+
+void enable_sched_clock_irqtime(void)
+{
+	sched_clock_irqtime = 1;
+}
+
+void disable_sched_clock_irqtime(void)
+{
+	sched_clock_irqtime = 0;
+}
+
+#ifndef CONFIG_64BIT
+static DEFINE_PER_CPU(seqcount_t, irq_time_seq);
+
+static inline void irq_time_write_begin(void)
+{
+	__this_cpu_inc(irq_time_seq.sequence);
+	smp_wmb();
+}
+
+static inline void irq_time_write_end(void)
+{
+	smp_wmb();
+	__this_cpu_inc(irq_time_seq.sequence);
+}
+
+static inline u64 irq_time_read(int cpu)
+{
+	u64 irq_time;
+	unsigned seq;
+
+	do {
+		seq = read_seqcount_begin(&per_cpu(irq_time_seq, cpu));
+		irq_time = per_cpu(cpu_softirq_time, cpu) +
+			   per_cpu(cpu_hardirq_time, cpu);
+	} while (read_seqcount_retry(&per_cpu(irq_time_seq, cpu), seq));
+
+	return irq_time;
+}
+#else /* CONFIG_64BIT */
+static inline void irq_time_write_begin(void)
+{
+}
+
+static inline void irq_time_write_end(void)
+{
+}
+
+static inline u64 irq_time_read(int cpu)
+{
+	return per_cpu(cpu_softirq_time, cpu) + per_cpu(cpu_hardirq_time, cpu);
+}
+#endif /* CONFIG_64BIT */
+
+/*
+ * Called before incrementing preempt_count on {soft,}irq_enter
+ * and before decrementing preempt_count on {soft,}irq_exit.
+ */
+void account_system_vtime(struct task_struct *curr)
+{
+	unsigned long flags;
+	s64 delta;
+	int cpu;
+
+	if (!sched_clock_irqtime)
+		return;
+
+	local_irq_save(flags);
+
+	cpu = smp_processor_id();
+	delta = sched_clock_cpu(cpu) - __this_cpu_read(irq_start_time);
+	__this_cpu_add(irq_start_time, delta);
+
+	irq_time_write_begin();
+	/*
+	 * We do not account for softirq time from ksoftirqd here.
+	 * We want to continue accounting softirq time to ksoftirqd thread
+	 * in that case, so as not to confuse scheduler with a special task
+	 * that do not consume any time, but still wants to run.
+	 */
+	if (hardirq_count())
+		__this_cpu_add(cpu_hardirq_time, delta);
+	else if (in_serving_softirq() && curr != this_cpu_ksoftirqd())
+		__this_cpu_add(cpu_softirq_time, delta);
+
+	irq_time_write_end();
+	local_irq_restore(flags);
+}
+EXPORT_SYMBOL_GPL(account_system_vtime);
+
+#endif /* CONFIG_IRQ_TIME_ACCOUNTING */
+
+#ifdef CONFIG_PARAVIRT
+static inline u64 steal_ticks(u64 steal)
+{
+	if (unlikely(steal > NSEC_PER_SEC))
+		return div_u64(steal, TICK_NSEC);
+
+	return __iter_div_u64_rem(steal, TICK_NSEC, &steal);
+}
+#endif
+
+static void update_rq_clock_task(struct rq *rq, s64 delta)
+{
+/*
+ * In theory, the compile should just see 0 here, and optimize out the call
+ * to sched_rt_avg_update. But I don't trust it...
+ */
+#if defined(CONFIG_IRQ_TIME_ACCOUNTING) || defined(CONFIG_PARAVIRT_TIME_ACCOUNTING)
+	s64 steal = 0, irq_delta = 0;
+#endif
+#ifdef CONFIG_IRQ_TIME_ACCOUNTING
+	irq_delta = irq_time_read(cpu_of(rq)) - rq->prev_irq_time;
+
+	/*
+	 * Since irq_time is only updated on {soft,}irq_exit, we might run into
+	 * this case when a previous update_rq_clock() happened inside a
+	 * {soft,}irq region.
+	 *
+	 * When this happens, we stop ->clock_task and only update the
+	 * prev_irq_time stamp to account for the part that fit, so that a next
+	 * update will consume the rest. This ensures ->clock_task is
+	 * monotonic.
+	 *
+	 * It does however cause some slight miss-attribution of {soft,}irq
+	 * time, a more accurate solution would be to update the irq_time using
+	 * the current rq->clock timestamp, except that would require using
+	 * atomic ops.
+	 */
+	if (irq_delta > delta)
+		irq_delta = delta;
+
+	rq->prev_irq_time += irq_delta;
+	delta -= irq_delta;
+#endif
+#ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
+	if (static_branch((&paravirt_steal_rq_enabled))) {
+		u64 st;
+
+		steal = paravirt_steal_clock(cpu_of(rq));
+		steal -= rq->prev_steal_time_rq;
+
+		if (unlikely(steal > delta))
+			steal = delta;
+
+		st = steal_ticks(steal);
+		steal = st * TICK_NSEC;
+
+		rq->prev_steal_time_rq += steal;
+
+		delta -= steal;
+	}
+#endif
+
+	rq->clock_task += delta;
+
+#if defined(CONFIG_IRQ_TIME_ACCOUNTING) || defined(CONFIG_PARAVIRT_TIME_ACCOUNTING)
+	if ((irq_delta + steal) && sched_feat(NONTASK_POWER))
+		sched_rt_avg_update(rq, irq_delta + steal);
+#endif
+}
+
+#ifdef CONFIG_IRQ_TIME_ACCOUNTING
+static int irqtime_account_hi_update(void)
+{
+	u64 *cpustat = kcpustat_this_cpu->cpustat;
+	unsigned long flags;
+	u64 latest_ns;
+	int ret = 0;
+
+	local_irq_save(flags);
+	latest_ns = this_cpu_read(cpu_hardirq_time);
+	if (nsecs_to_cputime64(latest_ns) > cpustat[CPUTIME_IRQ])
+		ret = 1;
+	local_irq_restore(flags);
+	return ret;
+}
+
+static int irqtime_account_si_update(void)
+{
+	u64 *cpustat = kcpustat_this_cpu->cpustat;
+	unsigned long flags;
+	u64 latest_ns;
+	int ret = 0;
+
+	local_irq_save(flags);
+	latest_ns = this_cpu_read(cpu_softirq_time);
+	if (nsecs_to_cputime64(latest_ns) > cpustat[CPUTIME_SOFTIRQ])
+		ret = 1;
+	local_irq_restore(flags);
+	return ret;
+}
+
+#else /* CONFIG_IRQ_TIME_ACCOUNTING */
+
+#define sched_clock_irqtime	(0)
+
+#endif
+
+void sched_set_stop_task(int cpu, struct task_struct *stop)
+{
+	struct sched_param param = { .sched_priority = MAX_RT_PRIO - 1 };
+	struct task_struct *old_stop = cpu_rq(cpu)->stop;
+
+	if (stop) {
+		/*
+		 * Make it appear like a SCHED_FIFO task, its something
+		 * userspace knows about and won't get confused about.
+		 *
+		 * Also, it will make PI more or less work without too
+		 * much confusion -- but then, stop work should not
+		 * rely on PI working anyway.
+		 */
+		sched_setscheduler_nocheck(stop, SCHED_FIFO, &param);
+
+		stop->sched_class = &stop_sched_class;
+	}
+
+	cpu_rq(cpu)->stop = stop;
+
+	if (old_stop) {
+		/*
+		 * Reset it back to a normal scheduling class so that
+		 * it can die in pieces.
+		 */
+		old_stop->sched_class = &rt_sched_class;
+	}
+}
+
+/*
+ * __normal_prio - return the priority that is based on the static prio
+ */
+static inline int __normal_prio(struct task_struct *p)
+{
+	return p->static_prio;
+}
+
+/*
+ * Calculate the expected normal priority: i.e. priority
+ * without taking RT-inheritance into account. Might be
+ * boosted by interactivity modifiers. Changes upon fork,
+ * setprio syscalls, and whenever the interactivity
+ * estimator recalculates.
+ */
+static inline int normal_prio(struct task_struct *p)
+{
+	int prio;
+
+	if (task_has_rt_policy(p))
+		prio = MAX_RT_PRIO-1 - p->rt_priority;
+	else
+		prio = __normal_prio(p);
+	return prio;
+}
+
+/*
+ * Calculate the current priority, i.e. the priority
+ * taken into account by the scheduler. This value might
+ * be boosted by RT tasks, or might be boosted by
+ * interactivity modifiers. Will be RT if the task got
+ * RT-boosted. If not then it returns p->normal_prio.
+ */
+static int effective_prio(struct task_struct *p)
+{
+	p->normal_prio = normal_prio(p);
+	/*
+	 * If we are RT tasks or we were boosted to RT priority,
+	 * keep the priority unchanged. Otherwise, update priority
+	 * to the normal priority:
+	 */
+	if (!rt_prio(p->prio))
+		return p->normal_prio;
+	return p->prio;
+}
+
+/**
+ * task_curr - is this task currently executing on a CPU?
+ * @p: the task in question.
+ */
+inline int task_curr(const struct task_struct *p)
+{
+	return cpu_curr(task_cpu(p)) == p;
+}
+
+static inline void check_class_changed(struct rq *rq, struct task_struct *p,
+				       const struct sched_class *prev_class,
+				       int oldprio)
+{
+	if (prev_class != p->sched_class) {
+		if (prev_class->switched_from)
+			prev_class->switched_from(rq, p);
+		p->sched_class->switched_to(rq, p);
+	} else if (oldprio != p->prio)
+		p->sched_class->prio_changed(rq, p, oldprio);
+}
+
+void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags)
+{
+	const struct sched_class *class;
+
+	if (p->sched_class == rq->curr->sched_class) {
+		rq->curr->sched_class->check_preempt_curr(rq, p, flags);
+	} else {
+		for_each_class(class) {
+			if (class == rq->curr->sched_class)
+				break;
+			if (class == p->sched_class) {
+				resched_task(rq->curr);
+				break;
+			}
+		}
+	}
+
+	/*
+	 * A queue event has occurred, and we're going to schedule.  In
+	 * this case, we can save a useless back to back clock update.
+	 */
+	if (rq->curr->on_rq && test_tsk_need_resched(rq->curr))
+		rq->skip_clock_update = 1;
+}
+
+#ifdef CONFIG_SMP
+void set_task_cpu(struct task_struct *p, unsigned int new_cpu)
+{
+#ifdef CONFIG_SCHED_DEBUG
+	/*
+	 * We should never call set_task_cpu() on a blocked task,
+	 * ttwu() will sort out the placement.
+	 */
+	WARN_ON_ONCE(p->state != TASK_RUNNING && p->state != TASK_WAKING &&
+			!(task_thread_info(p)->preempt_count & PREEMPT_ACTIVE));
+
+#ifdef CONFIG_LOCKDEP
+	/*
+	 * The caller should hold either p->pi_lock or rq->lock, when changing
+	 * a task's CPU. ->pi_lock for waking tasks, rq->lock for runnable tasks.
+	 *
+	 * sched_move_task() holds both and thus holding either pins the cgroup,
+	 * see set_task_rq().
+	 *
+	 * Furthermore, all task_rq users should acquire both locks, see
+	 * task_rq_lock().
+	 */
+	WARN_ON_ONCE(debug_locks && !(lockdep_is_held(&p->pi_lock) ||
+				      lockdep_is_held(&task_rq(p)->lock)));
+#endif
+#endif
+
+	trace_sched_migrate_task(p, new_cpu);
+
+	if (task_cpu(p) != new_cpu) {
+		p->se.nr_migrations++;
+		perf_sw_event(PERF_COUNT_SW_CPU_MIGRATIONS, 1, NULL, 0);
+	}
+
+	__set_task_cpu(p, new_cpu);
+}
+
+struct migration_arg {
+	struct task_struct *task;
+	int dest_cpu;
+};
+
+static int migration_cpu_stop(void *data);
+
+/*
+ * wait_task_inactive - wait for a thread to unschedule.
+ *
+ * If @match_state is nonzero, it's the @p->state value just checked and
+ * not expected to change.  If it changes, i.e. @p might have woken up,
+ * then return zero.  When we succeed in waiting for @p to be off its CPU,
+ * we return a positive number (its total switch count).  If a second call
+ * a short while later returns the same number, the caller can be sure that
+ * @p has remained unscheduled the whole time.
+ *
+ * The caller must ensure that the task *will* unschedule sometime soon,
+ * else this function might spin for a *long* time. This function can't
+ * be called with interrupts off, or it may introduce deadlock with
+ * smp_call_function() if an IPI is sent by the same process we are
+ * waiting to become inactive.
+ */
+unsigned long wait_task_inactive(struct task_struct *p, long match_state)
+{
+	unsigned long flags;
+	int running, on_rq;
+	unsigned long ncsw;
+	struct rq *rq;
+
+	for (;;) {
+		/*
+		 * We do the initial early heuristics without holding
+		 * any task-queue locks at all. We'll only try to get
+		 * the runqueue lock when things look like they will
+		 * work out!
+		 */
+		rq = task_rq(p);
+
+		/*
+		 * If the task is actively running on another CPU
+		 * still, just relax and busy-wait without holding
+		 * any locks.
+		 *
+		 * NOTE! Since we don't hold any locks, it's not
+		 * even sure that "rq" stays as the right runqueue!
+		 * But we don't care, since "task_running()" will
+		 * return false if the runqueue has changed and p
+		 * is actually now running somewhere else!
+		 */
+		while (task_running(rq, p)) {
+			if (match_state && unlikely(p->state != match_state))
+				return 0;
+			cpu_relax();
+		}
+
+		/*
+		 * Ok, time to look more closely! We need the rq
+		 * lock now, to be *sure*. If we're wrong, we'll
+		 * just go back and repeat.
+		 */
+		rq = task_rq_lock(p, &flags);
+		trace_sched_wait_task(p);
+		running = task_running(rq, p);
+		on_rq = p->on_rq;
+		ncsw = 0;
+		if (!match_state || p->state == match_state)
+			ncsw = p->nvcsw | LONG_MIN; /* sets MSB */
+		task_rq_unlock(rq, p, &flags);
+
+		/*
+		 * If it changed from the expected state, bail out now.
+		 */
+		if (unlikely(!ncsw))
+			break;
+
+		/*
+		 * Was it really running after all now that we
+		 * checked with the proper locks actually held?
+		 *
+		 * Oops. Go back and try again..
+		 */
+		if (unlikely(running)) {
+			cpu_relax();
+			continue;
+		}
+
+		/*
+		 * It's not enough that it's not actively running,
+		 * it must be off the runqueue _entirely_, and not
+		 * preempted!
+		 *
+		 * So if it was still runnable (but just not actively
+		 * running right now), it's preempted, and we should
+		 * yield - it could be a while.
+		 */
+		if (unlikely(on_rq)) {
+			ktime_t to = ktime_set(0, NSEC_PER_SEC/HZ);
+
+			set_current_state(TASK_UNINTERRUPTIBLE);
+			schedule_hrtimeout(&to, HRTIMER_MODE_REL);
+			continue;
+		}
+
+		/*
+		 * Ahh, all good. It wasn't running, and it wasn't
+		 * runnable, which means that it will never become
+		 * running in the future either. We're all done!
+		 */
+		break;
+	}
+
+	return ncsw;
+}
+
+/***
+ * kick_process - kick a running thread to enter/exit the kernel
+ * @p: the to-be-kicked thread
+ *
+ * Cause a process which is running on another CPU to enter
+ * kernel-mode, without any delay. (to get signals handled.)
+ *
+ * NOTE: this function doesn't have to take the runqueue lock,
+ * because all it wants to ensure is that the remote task enters
+ * the kernel. If the IPI races and the task has been migrated
+ * to another CPU then no harm is done and the purpose has been
+ * achieved as well.
+ */
+void kick_process(struct task_struct *p)
+{
+	int cpu;
+
+	preempt_disable();
+	cpu = task_cpu(p);
+	if ((cpu != smp_processor_id()) && task_curr(p))
+		smp_send_reschedule(cpu);
+	preempt_enable();
+}
+EXPORT_SYMBOL_GPL(kick_process);
+#endif /* CONFIG_SMP */
+
+#ifdef CONFIG_SMP
+/*
+ * ->cpus_allowed is protected by both rq->lock and p->pi_lock
+ */
+static int select_fallback_rq(int cpu, struct task_struct *p)
+{
+	int dest_cpu;
+	const struct cpumask *nodemask = cpumask_of_node(cpu_to_node(cpu));
+
+	/* Look for allowed, online CPU in same node. */
+	for_each_cpu_and(dest_cpu, nodemask, cpu_active_mask)
+		if (cpumask_test_cpu(dest_cpu, tsk_cpus_allowed(p)))
+			return dest_cpu;
+
+	/* Any allowed, online CPU? */
+	dest_cpu = cpumask_any_and(tsk_cpus_allowed(p), cpu_active_mask);
+	if (dest_cpu < nr_cpu_ids)
+		return dest_cpu;
+
+	/* No more Mr. Nice Guy. */
+	dest_cpu = cpuset_cpus_allowed_fallback(p);
+	/*
+	 * Don't tell them about moving exiting tasks or
+	 * kernel threads (both mm NULL), since they never
+	 * leave kernel.
+	 */
+	if (p->mm && printk_ratelimit()) {
+		printk(KERN_INFO "process %d (%s) no longer affine to cpu%d\n",
+				task_pid_nr(p), p->comm, cpu);
+	}
+
+	return dest_cpu;
+}
+
+/*
+ * The caller (fork, wakeup) owns p->pi_lock, ->cpus_allowed is stable.
+ */
+static inline
+int select_task_rq(struct task_struct *p, int sd_flags, int wake_flags)
+{
+	int cpu = p->sched_class->select_task_rq(p, sd_flags, wake_flags);
+
+	/*
+	 * In order not to call set_task_cpu() on a blocking task we need
+	 * to rely on ttwu() to place the task on a valid ->cpus_allowed
+	 * cpu.
+	 *
+	 * Since this is common to all placement strategies, this lives here.
+	 *
+	 * [ this allows ->select_task() to simply return task_cpu(p) and
+	 *   not worry about this generic constraint ]
+	 */
+	if (unlikely(!cpumask_test_cpu(cpu, tsk_cpus_allowed(p)) ||
+		     !cpu_online(cpu)))
+		cpu = select_fallback_rq(task_cpu(p), p);
+
+	return cpu;
+}
+
+static void update_avg(u64 *avg, u64 sample)
+{
+	s64 diff = sample - *avg;
+	*avg += diff >> 3;
+}
+#endif
+
+static void
+ttwu_stat(struct task_struct *p, int cpu, int wake_flags)
+{
+#ifdef CONFIG_SCHEDSTATS
+	struct rq *rq = this_rq();
+
+#ifdef CONFIG_SMP
+	int this_cpu = smp_processor_id();
+
+	if (cpu == this_cpu) {
+		schedstat_inc(rq, ttwu_local);
+		schedstat_inc(p, se.statistics.nr_wakeups_local);
+	} else {
+		struct sched_domain *sd;
+
+		schedstat_inc(p, se.statistics.nr_wakeups_remote);
+		rcu_read_lock();
+		for_each_domain(this_cpu, sd) {
+			if (cpumask_test_cpu(cpu, sched_domain_span(sd))) {
+				schedstat_inc(sd, ttwu_wake_remote);
+				break;
+			}
+		}
+		rcu_read_unlock();
+	}
+
+	if (wake_flags & WF_MIGRATED)
+		schedstat_inc(p, se.statistics.nr_wakeups_migrate);
+
+#endif /* CONFIG_SMP */
+
+	schedstat_inc(rq, ttwu_count);
+	schedstat_inc(p, se.statistics.nr_wakeups);
+
+	if (wake_flags & WF_SYNC)
+		schedstat_inc(p, se.statistics.nr_wakeups_sync);
+
+#endif /* CONFIG_SCHEDSTATS */
+}
+
+static void ttwu_activate(struct rq *rq, struct task_struct *p, int en_flags)
+{
+	activate_task(rq, p, en_flags);
+	p->on_rq = 1;
+
+	/* if a worker is waking up, notify workqueue */
+	if (p->flags & PF_WQ_WORKER)
+		wq_worker_waking_up(p, cpu_of(rq));
+}
+
+/*
+ * Mark the task runnable and perform wakeup-preemption.
+ */
+static void
+ttwu_do_wakeup(struct rq *rq, struct task_struct *p, int wake_flags)
+{
+	trace_sched_wakeup(p, true);
+	check_preempt_curr(rq, p, wake_flags);
+
+	p->state = TASK_RUNNING;
+#ifdef CONFIG_SMP
+	if (p->sched_class->task_woken)
+		p->sched_class->task_woken(rq, p);
+
+	if (rq->idle_stamp) {
+		u64 delta = rq->clock - rq->idle_stamp;
+		u64 max = 2*sysctl_sched_migration_cost;
+
+		if (delta > max)
+			rq->avg_idle = max;
+		else
+			update_avg(&rq->avg_idle, delta);
+		rq->idle_stamp = 0;
+	}
+#endif
+}
+
+static void
+ttwu_do_activate(struct rq *rq, struct task_struct *p, int wake_flags)
+{
+#ifdef CONFIG_SMP
+	if (p->sched_contributes_to_load)
+		rq->nr_uninterruptible--;
+#endif
+
+	ttwu_activate(rq, p, ENQUEUE_WAKEUP | ENQUEUE_WAKING);
+	ttwu_do_wakeup(rq, p, wake_flags);
+}
+
+/*
+ * Called in case the task @p isn't fully descheduled from its runqueue,
+ * in this case we must do a remote wakeup. Its a 'light' wakeup though,
+ * since all we need to do is flip p->state to TASK_RUNNING, since
+ * the task is still ->on_rq.
+ */
+static int ttwu_remote(struct task_struct *p, int wake_flags)
+{
+	struct rq *rq;
+	int ret = 0;
+
+	rq = __task_rq_lock(p);
+	if (p->on_rq) {
+		ttwu_do_wakeup(rq, p, wake_flags);
+		ret = 1;
+	}
+	__task_rq_unlock(rq);
+
+	return ret;
+}
+
+#ifdef CONFIG_SMP
+static void sched_ttwu_pending(void)
+{
+	struct rq *rq = this_rq();
+	struct llist_node *llist = llist_del_all(&rq->wake_list);
+	struct task_struct *p;
+
+	raw_spin_lock(&rq->lock);
+
+	while (llist) {
+		p = llist_entry(llist, struct task_struct, wake_entry);
+		llist = llist_next(llist);
+		ttwu_do_activate(rq, p, 0);
+	}
+
+	raw_spin_unlock(&rq->lock);
+}
+
+void scheduler_ipi(void)
+{
+	if (llist_empty(&this_rq()->wake_list) && !got_nohz_idle_kick())
+		return;
+
+	/*
+	 * Not all reschedule IPI handlers call irq_enter/irq_exit, since
+	 * traditionally all their work was done from the interrupt return
+	 * path. Now that we actually do some work, we need to make sure
+	 * we do call them.
+	 *
+	 * Some archs already do call them, luckily irq_enter/exit nest
+	 * properly.
+	 *
+	 * Arguably we should visit all archs and update all handlers,
+	 * however a fair share of IPIs are still resched only so this would
+	 * somewhat pessimize the simple resched case.
+	 */
+	irq_enter();
+	sched_ttwu_pending();
+
+	/*
+	 * Check if someone kicked us for doing the nohz idle load balance.
+	 */
+	if (unlikely(got_nohz_idle_kick() && !need_resched())) {
+		this_rq()->idle_balance = 1;
+		raise_softirq_irqoff(SCHED_SOFTIRQ);
+	}
+	irq_exit();
+}
+
+static void ttwu_queue_remote(struct task_struct *p, int cpu)
+{
+	if (llist_add(&p->wake_entry, &cpu_rq(cpu)->wake_list))
+		smp_send_reschedule(cpu);
+}
+
+#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
+static int ttwu_activate_remote(struct task_struct *p, int wake_flags)
+{
+	struct rq *rq;
+	int ret = 0;
+
+	rq = __task_rq_lock(p);
+	if (p->on_cpu) {
+		ttwu_activate(rq, p, ENQUEUE_WAKEUP);
+		ttwu_do_wakeup(rq, p, wake_flags);
+		ret = 1;
+	}
+	__task_rq_unlock(rq);
+
+	return ret;
+
+}
+#endif /* __ARCH_WANT_INTERRUPTS_ON_CTXSW */
+
+static inline int ttwu_share_cache(int this_cpu, int that_cpu)
+{
+	return per_cpu(sd_llc_id, this_cpu) == per_cpu(sd_llc_id, that_cpu);
+}
+#endif /* CONFIG_SMP */
+
+static void ttwu_queue(struct task_struct *p, int cpu)
+{
+	struct rq *rq = cpu_rq(cpu);
+
+#if defined(CONFIG_SMP)
+	if (sched_feat(TTWU_QUEUE) && !ttwu_share_cache(smp_processor_id(), cpu)) {
+		sched_clock_cpu(cpu); /* sync clocks x-cpu */
+		ttwu_queue_remote(p, cpu);
+		return;
+	}
+#endif
+
+	raw_spin_lock(&rq->lock);
+	ttwu_do_activate(rq, p, 0);
+	raw_spin_unlock(&rq->lock);
+}
+
+/**
+ * try_to_wake_up - wake up a thread
+ * @p: the thread to be awakened
+ * @state: the mask of task states that can be woken
+ * @wake_flags: wake modifier flags (WF_*)
+ *
+ * Put it on the run-queue if it's not already there. The "current"
+ * thread is always on the run-queue (except when the actual
+ * re-schedule is in progress), and as such you're allowed to do
+ * the simpler "current->state = TASK_RUNNING" to mark yourself
+ * runnable without the overhead of this.
+ *
+ * Returns %true if @p was woken up, %false if it was already running
+ * or @state didn't match @p's state.
+ */
+static int
+try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
+{
+	unsigned long flags;
+	int cpu, success = 0;
+
+	smp_wmb();
+	raw_spin_lock_irqsave(&p->pi_lock, flags);
+	if (!(p->state & state))
+		goto out;
+
+	success = 1; /* we're going to change ->state */
+	cpu = task_cpu(p);
+
+	if (p->on_rq && ttwu_remote(p, wake_flags))
+		goto stat;
+
+#ifdef CONFIG_SMP
+	/*
+	 * If the owning (remote) cpu is still in the middle of schedule() with
+	 * this task as prev, wait until its done referencing the task.
+	 */
+	while (p->on_cpu) {
+#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
+		/*
+		 * In case the architecture enables interrupts in
+		 * context_switch(), we cannot busy wait, since that
+		 * would lead to deadlocks when an interrupt hits and
+		 * tries to wake up @prev. So bail and do a complete
+		 * remote wakeup.
+		 */
+		if (ttwu_activate_remote(p, wake_flags))
+			goto stat;
+#else
+		cpu_relax();
+#endif
+	}
+	/*
+	 * Pairs with the smp_wmb() in finish_lock_switch().
+	 */
+	smp_rmb();
+
+	p->sched_contributes_to_load = !!task_contributes_to_load(p);
+	p->state = TASK_WAKING;
+
+	if (p->sched_class->task_waking)
+		p->sched_class->task_waking(p);
+
+	cpu = select_task_rq(p, SD_BALANCE_WAKE, wake_flags);
+	if (task_cpu(p) != cpu) {
+		wake_flags |= WF_MIGRATED;
+		set_task_cpu(p, cpu);
+	}
+#endif /* CONFIG_SMP */
+
+	ttwu_queue(p, cpu);
+stat:
+	ttwu_stat(p, cpu, wake_flags);
+out:
+	raw_spin_unlock_irqrestore(&p->pi_lock, flags);
+
+	return success;
+}
+
+/**
+ * try_to_wake_up_local - try to wake up a local task with rq lock held
+ * @p: the thread to be awakened
+ *
+ * Put @p on the run-queue if it's not already there. The caller must
+ * ensure that this_rq() is locked, @p is bound to this_rq() and not
+ * the current task.
+ */
+static void try_to_wake_up_local(struct task_struct *p)
+{
+	struct rq *rq = task_rq(p);
+
+	BUG_ON(rq != this_rq());
+	BUG_ON(p == current);
+	lockdep_assert_held(&rq->lock);
+
+	if (!raw_spin_trylock(&p->pi_lock)) {
+		raw_spin_unlock(&rq->lock);
+		raw_spin_lock(&p->pi_lock);
+		raw_spin_lock(&rq->lock);
+	}
+
+	if (!(p->state & TASK_NORMAL))
+		goto out;
+
+	if (!p->on_rq)
+		ttwu_activate(rq, p, ENQUEUE_WAKEUP);
+
+	ttwu_do_wakeup(rq, p, 0);
+	ttwu_stat(p, smp_processor_id(), 0);
+out:
+	raw_spin_unlock(&p->pi_lock);
+}
+
+/**
+ * wake_up_process - Wake up a specific process
+ * @p: The process to be woken up.
+ *
+ * Attempt to wake up the nominated process and move it to the set of runnable
+ * processes.  Returns 1 if the process was woken up, 0 if it was already
+ * running.
+ *
+ * It may be assumed that this function implies a write memory barrier before
+ * changing the task state if and only if any tasks are woken up.
+ */
+int wake_up_process(struct task_struct *p)
+{
+	return try_to_wake_up(p, TASK_ALL, 0);
+}
+EXPORT_SYMBOL(wake_up_process);
+
+int wake_up_state(struct task_struct *p, unsigned int state)
+{
+	return try_to_wake_up(p, state, 0);
+}
+
+/*
+ * Perform scheduler related setup for a newly forked process p.
+ * p is forked by current.
+ *
+ * __sched_fork() is basic setup used by init_idle() too:
+ */
+static void __sched_fork(struct task_struct *p)
+{
+	p->on_rq			= 0;
+
+	p->se.on_rq			= 0;
+	p->se.exec_start		= 0;
+	p->se.sum_exec_runtime		= 0;
+	p->se.prev_sum_exec_runtime	= 0;
+	p->se.nr_migrations		= 0;
+	p->se.vruntime			= 0;
+	INIT_LIST_HEAD(&p->se.group_node);
+
+#ifdef CONFIG_SCHEDSTATS
+	memset(&p->se.statistics, 0, sizeof(p->se.statistics));
+#endif
+
+	INIT_LIST_HEAD(&p->rt.run_list);
+
+#ifdef CONFIG_PREEMPT_NOTIFIERS
+	INIT_HLIST_HEAD(&p->preempt_notifiers);
+#endif
+}
+
+/*
+ * fork()/clone()-time setup:
+ */
+void sched_fork(struct task_struct *p)
+{
+	unsigned long flags;
+	int cpu = get_cpu();
+
+	__sched_fork(p);
+	/*
+	 * We mark the process as running here. This guarantees that
+	 * nobody will actually run it, and a signal or other external
+	 * event cannot wake it up and insert it on the runqueue either.
+	 */
+	p->state = TASK_RUNNING;
+
+	/*
+	 * Make sure we do not leak PI boosting priority to the child.
+	 */
+	p->prio = current->normal_prio;
+
+	/*
+	 * Revert to default priority/policy on fork if requested.
+	 */
+	if (unlikely(p->sched_reset_on_fork)) {
+		if (task_has_rt_policy(p)) {
+			p->policy = SCHED_NORMAL;
+			p->static_prio = NICE_TO_PRIO(0);
+			p->rt_priority = 0;
+		} else if (PRIO_TO_NICE(p->static_prio) < 0)
+			p->static_prio = NICE_TO_PRIO(0);
+
+		p->prio = p->normal_prio = __normal_prio(p);
+		set_load_weight(p);
+
+		/*
+		 * We don't need the reset flag anymore after the fork. It has
+		 * fulfilled its duty:
+		 */
+		p->sched_reset_on_fork = 0;
+	}
+
+	if (!rt_prio(p->prio))
+		p->sched_class = &fair_sched_class;
+
+	if (p->sched_class->task_fork)
+		p->sched_class->task_fork(p);
+
+	/*
+	 * The child is not yet in the pid-hash so no cgroup attach races,
+	 * and the cgroup is pinned to this child due to cgroup_fork()
+	 * is ran before sched_fork().
+	 *
+	 * Silence PROVE_RCU.
+	 */
+	raw_spin_lock_irqsave(&p->pi_lock, flags);
+	set_task_cpu(p, cpu);
+	raw_spin_unlock_irqrestore(&p->pi_lock, flags);
+
+#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
+	if (likely(sched_info_on()))
+		memset(&p->sched_info, 0, sizeof(p->sched_info));
+#endif
+#if defined(CONFIG_SMP)
+	p->on_cpu = 0;
+#endif
+#ifdef CONFIG_PREEMPT_COUNT
+	/* Want to start with kernel preemption disabled. */
+	task_thread_info(p)->preempt_count = 1;
+#endif
+#ifdef CONFIG_SMP
+	plist_node_init(&p->pushable_tasks, MAX_PRIO);
+#endif
+
+	put_cpu();
+}
+
+/*
+ * wake_up_new_task - wake up a newly created task for the first time.
+ *
+ * This function will do some initial scheduler statistics housekeeping
+ * that must be done for every newly created context, then puts the task
+ * on the runqueue and wakes it.
+ */
+void wake_up_new_task(struct task_struct *p)
+{
+	unsigned long flags;
+	struct rq *rq;
+
+	raw_spin_lock_irqsave(&p->pi_lock, flags);
+#ifdef CONFIG_SMP
+	/*
+	 * Fork balancing, do it here and not earlier because:
+	 *  - cpus_allowed can change in the fork path
+	 *  - any previously selected cpu might disappear through hotplug
+	 */
+	set_task_cpu(p, select_task_rq(p, SD_BALANCE_FORK, 0));
+#endif
+
+	rq = __task_rq_lock(p);
+	activate_task(rq, p, 0);
+	p->on_rq = 1;
+	trace_sched_wakeup_new(p, true);
+	check_preempt_curr(rq, p, WF_FORK);
+#ifdef CONFIG_SMP
+	if (p->sched_class->task_woken)
+		p->sched_class->task_woken(rq, p);
+#endif
+	task_rq_unlock(rq, p, &flags);
+}
+
+#ifdef CONFIG_PREEMPT_NOTIFIERS
+
+/**
+ * preempt_notifier_register - tell me when current is being preempted & rescheduled
+ * @notifier: notifier struct to register
+ */
+void preempt_notifier_register(struct preempt_notifier *notifier)
+{
+	hlist_add_head(&notifier->link, &current->preempt_notifiers);
+}
+EXPORT_SYMBOL_GPL(preempt_notifier_register);
+
+/**
+ * preempt_notifier_unregister - no longer interested in preemption notifications
+ * @notifier: notifier struct to unregister
+ *
+ * This is safe to call from within a preemption notifier.
+ */
+void preempt_notifier_unregister(struct preempt_notifier *notifier)
+{
+	hlist_del(&notifier->link);
+}
+EXPORT_SYMBOL_GPL(preempt_notifier_unregister);
+
+static void fire_sched_in_preempt_notifiers(struct task_struct *curr)
+{
+	struct preempt_notifier *notifier;
+	struct hlist_node *node;
+
+	hlist_for_each_entry(notifier, node, &curr->preempt_notifiers, link)
+		notifier->ops->sched_in(notifier, raw_smp_processor_id());
+}
+
+static void
+fire_sched_out_preempt_notifiers(struct task_struct *curr,
+				 struct task_struct *next)
+{
+	struct preempt_notifier *notifier;
+	struct hlist_node *node;
+
+	hlist_for_each_entry(notifier, node, &curr->preempt_notifiers, link)
+		notifier->ops->sched_out(notifier, next);
+}
+
+#else /* !CONFIG_PREEMPT_NOTIFIERS */
+
+static void fire_sched_in_preempt_notifiers(struct task_struct *curr)
+{
+}
+
+static void
+fire_sched_out_preempt_notifiers(struct task_struct *curr,
+				 struct task_struct *next)
+{
+}
+
+#endif /* CONFIG_PREEMPT_NOTIFIERS */
+
+/**
+ * prepare_task_switch - prepare to switch tasks
+ * @rq: the runqueue preparing to switch
+ * @prev: the current task that is being switched out
+ * @next: the task we are going to switch to.
+ *
+ * This is called with the rq lock held and interrupts off. It must
+ * be paired with a subsequent finish_task_switch after the context
+ * switch.
+ *
+ * prepare_task_switch sets up locking and calls architecture specific
+ * hooks.
+ */
+static inline void
+prepare_task_switch(struct rq *rq, struct task_struct *prev,
+		    struct task_struct *next)
+{
+	sched_info_switch(prev, next);
+	perf_event_task_sched_out(prev, next);
+	fire_sched_out_preempt_notifiers(prev, next);
+	prepare_lock_switch(rq, next);
+	prepare_arch_switch(next);
+	trace_sched_switch(prev, next);
+}
+
+/**
+ * finish_task_switch - clean up after a task-switch
+ * @rq: runqueue associated with task-switch
+ * @prev: the thread we just switched away from.
+ *
+ * finish_task_switch must be called after the context switch, paired
+ * with a prepare_task_switch call before the context switch.
+ * finish_task_switch will reconcile locking set up by prepare_task_switch,
+ * and do any other architecture-specific cleanup actions.
+ *
+ * Note that we may have delayed dropping an mm in context_switch(). If
+ * so, we finish that here outside of the runqueue lock. (Doing it
+ * with the lock held can cause deadlocks; see schedule() for
+ * details.)
+ */
+static void finish_task_switch(struct rq *rq, struct task_struct *prev)
+	__releases(rq->lock)
+{
+	struct mm_struct *mm = rq->prev_mm;
+	long prev_state;
+
+	rq->prev_mm = NULL;
+
+	/*
+	 * A task struct has one reference for the use as "current".
+	 * If a task dies, then it sets TASK_DEAD in tsk->state and calls
+	 * schedule one last time. The schedule call will never return, and
+	 * the scheduled task must drop that reference.
+	 * The test for TASK_DEAD must occur while the runqueue locks are
+	 * still held, otherwise prev could be scheduled on another cpu, die
+	 * there before we look at prev->state, and then the reference would
+	 * be dropped twice.
+	 *		Manfred Spraul <manfred@colorfullife.com>
+	 */
+	prev_state = prev->state;
+	finish_arch_switch(prev);
+#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
+	local_irq_disable();
+#endif /* __ARCH_WANT_INTERRUPTS_ON_CTXSW */
+	perf_event_task_sched_in(prev, current);
+#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
+	local_irq_enable();
+#endif /* __ARCH_WANT_INTERRUPTS_ON_CTXSW */
+	finish_lock_switch(rq, prev);
+	trace_sched_stat_sleeptime(current, rq->clock);
+
+	fire_sched_in_preempt_notifiers(current);
+	if (mm)
+		mmdrop(mm);
+	if (unlikely(prev_state == TASK_DEAD)) {
+		/*
+		 * Remove function-return probe instances associated with this
+		 * task and put them back on the free list.
+		 */
+		kprobe_flush_task(prev);
+		put_task_struct(prev);
+	}
+}
+
+#ifdef CONFIG_SMP
+
+/* assumes rq->lock is held */
+static inline void pre_schedule(struct rq *rq, struct task_struct *prev)
+{
+	if (prev->sched_class->pre_schedule)
+		prev->sched_class->pre_schedule(rq, prev);
+}
+
+/* rq->lock is NOT held, but preemption is disabled */
+static inline void post_schedule(struct rq *rq)
+{
+	if (rq->post_schedule) {
+		unsigned long flags;
+
+		raw_spin_lock_irqsave(&rq->lock, flags);
+		if (rq->curr->sched_class->post_schedule)
+			rq->curr->sched_class->post_schedule(rq);
+		raw_spin_unlock_irqrestore(&rq->lock, flags);
+
+		rq->post_schedule = 0;
+	}
+}
+
+#else
+
+static inline void pre_schedule(struct rq *rq, struct task_struct *p)
+{
+}
+
+static inline void post_schedule(struct rq *rq)
+{
+}
+
+#endif
+
+/**
+ * schedule_tail - first thing a freshly forked thread must call.
+ * @prev: the thread we just switched away from.
+ */
+asmlinkage void schedule_tail(struct task_struct *prev)
+	__releases(rq->lock)
+{
+	struct rq *rq = this_rq();
+
+	finish_task_switch(rq, prev);
+
+	/*
+	 * FIXME: do we need to worry about rq being invalidated by the
+	 * task_switch?
+	 */
+	post_schedule(rq);
+
+#ifdef __ARCH_WANT_UNLOCKED_CTXSW
+	/* In this case, finish_task_switch does not reenable preemption */
+	preempt_enable();
+#endif
+	if (current->set_child_tid)
+		put_user(task_pid_vnr(current), current->set_child_tid);
+}
+
+/*
+ * context_switch - switch to the new MM and the new
+ * thread's register state.
+ */
+static inline void
+context_switch(struct rq *rq, struct task_struct *prev,
+	       struct task_struct *next)
+{
+	struct mm_struct *mm, *oldmm;
+
+	prepare_task_switch(rq, prev, next);
+
+	mm = next->mm;
+	oldmm = prev->active_mm;
+	/*
+	 * For paravirt, this is coupled with an exit in switch_to to
+	 * combine the page table reload and the switch backend into
+	 * one hypercall.
+	 */
+	arch_start_context_switch(prev);
+
+	if (!mm) {
+		next->active_mm = oldmm;
+		atomic_inc(&oldmm->mm_count);
+		enter_lazy_tlb(oldmm, next);
+	} else
+		switch_mm(oldmm, mm, next);
+
+	if (!prev->mm) {
+		prev->active_mm = NULL;
+		rq->prev_mm = oldmm;
+	}
+	/*
+	 * Since the runqueue lock will be released by the next
+	 * task (which is an invalid locking op but in the case
+	 * of the scheduler it's an obvious special-case), so we
+	 * do an early lockdep release here:
+	 */
+#ifndef __ARCH_WANT_UNLOCKED_CTXSW
+	spin_release(&rq->lock.dep_map, 1, _THIS_IP_);
+#endif
+
+	/* Here we just switch the register state and the stack. */
+	switch_to(prev, next, prev);
+
+	barrier();
+	/*
+	 * this_rq must be evaluated again because prev may have moved
+	 * CPUs since it called schedule(), thus the 'rq' on its stack
+	 * frame will be invalid.
+	 */
+	finish_task_switch(this_rq(), prev);
+}
+
+/*
+ * nr_running, nr_uninterruptible and nr_context_switches:
+ *
+ * externally visible scheduler statistics: current number of runnable
+ * threads, current number of uninterruptible-sleeping threads, total
+ * number of context switches performed since bootup.
+ */
+unsigned long nr_running(void)
+{
+	unsigned long i, sum = 0;
+
+	for_each_online_cpu(i)
+		sum += cpu_rq(i)->nr_running;
+
+	return sum;
+}
+
+unsigned long nr_uninterruptible(void)
+{
+	unsigned long i, sum = 0;
+
+	for_each_possible_cpu(i)
+		sum += cpu_rq(i)->nr_uninterruptible;
+
+	/*
+	 * Since we read the counters lockless, it might be slightly
+	 * inaccurate. Do not allow it to go below zero though:
+	 */
+	if (unlikely((long)sum < 0))
+		sum = 0;
+
+	return sum;
+}
+
+unsigned long long nr_context_switches(void)
+{
+	int i;
+	unsigned long long sum = 0;
+
+	for_each_possible_cpu(i)
+		sum += cpu_rq(i)->nr_switches;
+
+	return sum;
+}
+
+unsigned long nr_iowait(void)
+{
+	unsigned long i, sum = 0;
+
+	for_each_possible_cpu(i)
+		sum += atomic_read(&cpu_rq(i)->nr_iowait);
+
+	return sum;
+}
+
+unsigned long nr_iowait_cpu(int cpu)
+{
+	struct rq *this = cpu_rq(cpu);
+	return atomic_read(&this->nr_iowait);
+}
+
+unsigned long this_cpu_load(void)
+{
+	struct rq *this = this_rq();
+	return this->cpu_load[0];
+}
+
+
+/* Variables and functions for calc_load */
+static atomic_long_t calc_load_tasks;
+static unsigned long calc_load_update;
+unsigned long avenrun[3];
+EXPORT_SYMBOL(avenrun);
+
+static long calc_load_fold_active(struct rq *this_rq)
+{
+	long nr_active, delta = 0;
+
+	nr_active = this_rq->nr_running;
+	nr_active += (long) this_rq->nr_uninterruptible;
+
+	if (nr_active != this_rq->calc_load_active) {
+		delta = nr_active - this_rq->calc_load_active;
+		this_rq->calc_load_active = nr_active;
+	}
+
+	return delta;
+}
+
+static unsigned long
+calc_load(unsigned long load, unsigned long exp, unsigned long active)
+{
+	load *= exp;
+	load += active * (FIXED_1 - exp);
+	load += 1UL << (FSHIFT - 1);
+	return load >> FSHIFT;
+}
+
+#ifdef CONFIG_NO_HZ
+/*
+ * For NO_HZ we delay the active fold to the next LOAD_FREQ update.
+ *
+ * When making the ILB scale, we should try to pull this in as well.
+ */
+static atomic_long_t calc_load_tasks_idle;
+
+void calc_load_account_idle(struct rq *this_rq)
+{
+	long delta;
+
+	delta = calc_load_fold_active(this_rq);
+	if (delta)
+		atomic_long_add(delta, &calc_load_tasks_idle);
+}
+
+static long calc_load_fold_idle(void)
+{
+	long delta = 0;
+
+	/*
+	 * Its got a race, we don't care...
+	 */
+	if (atomic_long_read(&calc_load_tasks_idle))
+		delta = atomic_long_xchg(&calc_load_tasks_idle, 0);
+
+	return delta;
+}
+
+/**
+ * fixed_power_int - compute: x^n, in O(log n) time
+ *
+ * @x:         base of the power
+ * @frac_bits: fractional bits of @x
+ * @n:         power to raise @x to.
+ *
+ * By exploiting the relation between the definition of the natural power
+ * function: x^n := x*x*...*x (x multiplied by itself for n times), and
+ * the binary encoding of numbers used by computers: n := \Sum n_i * 2^i,
+ * (where: n_i \elem {0, 1}, the binary vector representing n),
+ * we find: x^n := x^(\Sum n_i * 2^i) := \Prod x^(n_i * 2^i), which is
+ * of course trivially computable in O(log_2 n), the length of our binary
+ * vector.
+ */
+static unsigned long
+fixed_power_int(unsigned long x, unsigned int frac_bits, unsigned int n)
+{
+	unsigned long result = 1UL << frac_bits;
+
+	if (n) for (;;) {
+		if (n & 1) {
+			result *= x;
+			result += 1UL << (frac_bits - 1);
+			result >>= frac_bits;
+		}
+		n >>= 1;
+		if (!n)
+			break;
+		x *= x;
+		x += 1UL << (frac_bits - 1);
+		x >>= frac_bits;
+	}
+
+	return result;
+}
+
+/*
+ * a1 = a0 * e + a * (1 - e)
+ *
+ * a2 = a1 * e + a * (1 - e)
+ *    = (a0 * e + a * (1 - e)) * e + a * (1 - e)
+ *    = a0 * e^2 + a * (1 - e) * (1 + e)
+ *
+ * a3 = a2 * e + a * (1 - e)
+ *    = (a0 * e^2 + a * (1 - e) * (1 + e)) * e + a * (1 - e)
+ *    = a0 * e^3 + a * (1 - e) * (1 + e + e^2)
+ *
+ *  ...
+ *
+ * an = a0 * e^n + a * (1 - e) * (1 + e + ... + e^n-1) [1]
+ *    = a0 * e^n + a * (1 - e) * (1 - e^n)/(1 - e)
+ *    = a0 * e^n + a * (1 - e^n)
+ *
+ * [1] application of the geometric series:
+ *
+ *              n         1 - x^(n+1)
+ *     S_n := \Sum x^i = -------------
+ *             i=0          1 - x
+ */
+static unsigned long
+calc_load_n(unsigned long load, unsigned long exp,
+	    unsigned long active, unsigned int n)
+{
+
+	return calc_load(load, fixed_power_int(exp, FSHIFT, n), active);
+}
+
+/*
+ * NO_HZ can leave us missing all per-cpu ticks calling
+ * calc_load_account_active(), but since an idle CPU folds its delta into
+ * calc_load_tasks_idle per calc_load_account_idle(), all we need to do is fold
+ * in the pending idle delta if our idle period crossed a load cycle boundary.
+ *
+ * Once we've updated the global active value, we need to apply the exponential
+ * weights adjusted to the number of cycles missed.
+ */
+static void calc_global_nohz(unsigned long ticks)
+{
+	long delta, active, n;
+
+	if (time_before(jiffies, calc_load_update))
+		return;
+
+	/*
+	 * If we crossed a calc_load_update boundary, make sure to fold
+	 * any pending idle changes, the respective CPUs might have
+	 * missed the tick driven calc_load_account_active() update
+	 * due to NO_HZ.
+	 */
+	delta = calc_load_fold_idle();
+	if (delta)
+		atomic_long_add(delta, &calc_load_tasks);
+
+	/*
+	 * If we were idle for multiple load cycles, apply them.
+	 */
+	if (ticks >= LOAD_FREQ) {
+		n = ticks / LOAD_FREQ;
+
+		active = atomic_long_read(&calc_load_tasks);
+		active = active > 0 ? active * FIXED_1 : 0;
+
+		avenrun[0] = calc_load_n(avenrun[0], EXP_1, active, n);
+		avenrun[1] = calc_load_n(avenrun[1], EXP_5, active, n);
+		avenrun[2] = calc_load_n(avenrun[2], EXP_15, active, n);
+
+		calc_load_update += n * LOAD_FREQ;
+	}
+
+	/*
+	 * Its possible the remainder of the above division also crosses
+	 * a LOAD_FREQ period, the regular check in calc_global_load()
+	 * which comes after this will take care of that.
+	 *
+	 * Consider us being 11 ticks before a cycle completion, and us
+	 * sleeping for 4*LOAD_FREQ + 22 ticks, then the above code will
+	 * age us 4 cycles, and the test in calc_global_load() will
+	 * pick up the final one.
+	 */
+}
+#else
+void calc_load_account_idle(struct rq *this_rq)
+{
+}
+
+static inline long calc_load_fold_idle(void)
+{
+	return 0;
+}
+
+static void calc_global_nohz(unsigned long ticks)
+{
+}
+#endif
+
+/**
+ * get_avenrun - get the load average array
+ * @loads:	pointer to dest load array
+ * @offset:	offset to add
+ * @shift:	shift count to shift the result left
+ *
+ * These values are estimates at best, so no need for locking.
+ */
+void get_avenrun(unsigned long *loads, unsigned long offset, int shift)
+{
+	loads[0] = (avenrun[0] + offset) << shift;
+	loads[1] = (avenrun[1] + offset) << shift;
+	loads[2] = (avenrun[2] + offset) << shift;
+}
+
+/*
+ * calc_load - update the avenrun load estimates 10 ticks after the
+ * CPUs have updated calc_load_tasks.
+ */
+void calc_global_load(unsigned long ticks)
+{
+	long active;
+
+	calc_global_nohz(ticks);
+
+	if (time_before(jiffies, calc_load_update + 10))
+		return;
+
+	active = atomic_long_read(&calc_load_tasks);
+	active = active > 0 ? active * FIXED_1 : 0;
+
+	avenrun[0] = calc_load(avenrun[0], EXP_1, active);
+	avenrun[1] = calc_load(avenrun[1], EXP_5, active);
+	avenrun[2] = calc_load(avenrun[2], EXP_15, active);
+
+	calc_load_update += LOAD_FREQ;
+}
+
+/*
+ * Called from update_cpu_load() to periodically update this CPU's
+ * active count.
+ */
+static void calc_load_account_active(struct rq *this_rq)
+{
+	long delta;
+
+	if (time_before(jiffies, this_rq->calc_load_update))
+		return;
+
+	delta  = calc_load_fold_active(this_rq);
+	delta += calc_load_fold_idle();
+	if (delta)
+		atomic_long_add(delta, &calc_load_tasks);
+
+	this_rq->calc_load_update += LOAD_FREQ;
+}
+
+/*
+ * The exact cpuload at various idx values, calculated at every tick would be
+ * load = (2^idx - 1) / 2^idx * load + 1 / 2^idx * cur_load
+ *
+ * If a cpu misses updates for n-1 ticks (as it was idle) and update gets called
+ * on nth tick when cpu may be busy, then we have:
+ * load = ((2^idx - 1) / 2^idx)^(n-1) * load
+ * load = (2^idx - 1) / 2^idx) * load + 1 / 2^idx * cur_load
+ *
+ * decay_load_missed() below does efficient calculation of
+ * load = ((2^idx - 1) / 2^idx)^(n-1) * load
+ * avoiding 0..n-1 loop doing load = ((2^idx - 1) / 2^idx) * load
+ *
+ * The calculation is approximated on a 128 point scale.
+ * degrade_zero_ticks is the number of ticks after which load at any
+ * particular idx is approximated to be zero.
+ * degrade_factor is a precomputed table, a row for each load idx.
+ * Each column corresponds to degradation factor for a power of two ticks,
+ * based on 128 point scale.
+ * Example:
+ * row 2, col 3 (=12) says that the degradation at load idx 2 after
+ * 8 ticks is 12/128 (which is an approximation of exact factor 3^8/4^8).
+ *
+ * With this power of 2 load factors, we can degrade the load n times
+ * by looking at 1 bits in n and doing as many mult/shift instead of
+ * n mult/shifts needed by the exact degradation.
+ */
+#define DEGRADE_SHIFT		7
+static const unsigned char
+		degrade_zero_ticks[CPU_LOAD_IDX_MAX] = {0, 8, 32, 64, 128};
+static const unsigned char
+		degrade_factor[CPU_LOAD_IDX_MAX][DEGRADE_SHIFT + 1] = {
+					{0, 0, 0, 0, 0, 0, 0, 0},
+					{64, 32, 8, 0, 0, 0, 0, 0},
+					{96, 72, 40, 12, 1, 0, 0},
+					{112, 98, 75, 43, 15, 1, 0},
+					{120, 112, 98, 76, 45, 16, 2} };
+
+/*
+ * Update cpu_load for any missed ticks, due to tickless idle. The backlog
+ * would be when CPU is idle and so we just decay the old load without
+ * adding any new load.
+ */
+static unsigned long
+decay_load_missed(unsigned long load, unsigned long missed_updates, int idx)
+{
+	int j = 0;
+
+	if (!missed_updates)
+		return load;
+
+	if (missed_updates >= degrade_zero_ticks[idx])
+		return 0;
+
+	if (idx == 1)
+		return load >> missed_updates;
+
+	while (missed_updates) {
+		if (missed_updates % 2)
+			load = (load * degrade_factor[idx][j]) >> DEGRADE_SHIFT;
+
+		missed_updates >>= 1;
+		j++;
+	}
+	return load;
+}
+
+/*
+ * Update rq->cpu_load[] statistics. This function is usually called every
+ * scheduler tick (TICK_NSEC). With tickless idle this will not be called
+ * every tick. We fix it up based on jiffies.
+ */
+void update_cpu_load(struct rq *this_rq)
+{
+	unsigned long this_load = this_rq->load.weight;
+	unsigned long curr_jiffies = jiffies;
+	unsigned long pending_updates;
+	int i, scale;
+
+	this_rq->nr_load_updates++;
+
+	/* Avoid repeated calls on same jiffy, when moving in and out of idle */
+	if (curr_jiffies == this_rq->last_load_update_tick)
+		return;
+
+	pending_updates = curr_jiffies - this_rq->last_load_update_tick;
+	this_rq->last_load_update_tick = curr_jiffies;
+
+	/* Update our load: */
+	this_rq->cpu_load[0] = this_load; /* Fasttrack for idx 0 */
+	for (i = 1, scale = 2; i < CPU_LOAD_IDX_MAX; i++, scale += scale) {
+		unsigned long old_load, new_load;
+
+		/* scale is effectively 1 << i now, and >> i divides by scale */
+
+		old_load = this_rq->cpu_load[i];
+		old_load = decay_load_missed(old_load, pending_updates - 1, i);
+		new_load = this_load;
+		/*
+		 * Round up the averaging division if load is increasing. This
+		 * prevents us from getting stuck on 9 if the load is 10, for
+		 * example.
+		 */
+		if (new_load > old_load)
+			new_load += scale - 1;
+
+		this_rq->cpu_load[i] = (old_load * (scale - 1) + new_load) >> i;
+	}
+
+	sched_avg_update(this_rq);
+}
+
+static void update_cpu_load_active(struct rq *this_rq)
+{
+	update_cpu_load(this_rq);
+
+	calc_load_account_active(this_rq);
+}
+
+#ifdef CONFIG_SMP
+
+/*
+ * sched_exec - execve() is a valuable balancing opportunity, because at
+ * this point the task has the smallest effective memory and cache footprint.
+ */
+void sched_exec(void)
+{
+	struct task_struct *p = current;
+	unsigned long flags;
+	int dest_cpu;
+
+	raw_spin_lock_irqsave(&p->pi_lock, flags);
+	dest_cpu = p->sched_class->select_task_rq(p, SD_BALANCE_EXEC, 0);
+	if (dest_cpu == smp_processor_id())
+		goto unlock;
+
+	if (likely(cpu_active(dest_cpu))) {
+		struct migration_arg arg = { p, dest_cpu };
+
+		raw_spin_unlock_irqrestore(&p->pi_lock, flags);
+		stop_one_cpu(task_cpu(p), migration_cpu_stop, &arg);
+		return;
+	}
+unlock:
+	raw_spin_unlock_irqrestore(&p->pi_lock, flags);
+}
+
+#endif
+
+DEFINE_PER_CPU(struct kernel_stat, kstat);
+DEFINE_PER_CPU(struct kernel_cpustat, kernel_cpustat);
+
+EXPORT_PER_CPU_SYMBOL(kstat);
+EXPORT_PER_CPU_SYMBOL(kernel_cpustat);
+
+/*
+ * Return any ns on the sched_clock that have not yet been accounted in
+ * @p in case that task is currently running.
+ *
+ * Called with task_rq_lock() held on @rq.
+ */
+static u64 do_task_delta_exec(struct task_struct *p, struct rq *rq)
+{
+	u64 ns = 0;
+
+	if (task_current(rq, p)) {
+		update_rq_clock(rq);
+		ns = rq->clock_task - p->se.exec_start;
+		if ((s64)ns < 0)
+			ns = 0;
+	}
+
+	return ns;
+}
+
+unsigned long long task_delta_exec(struct task_struct *p)
+{
+	unsigned long flags;
+	struct rq *rq;
+	u64 ns = 0;
+
+	rq = task_rq_lock(p, &flags);
+	ns = do_task_delta_exec(p, rq);
+	task_rq_unlock(rq, p, &flags);
+
+	return ns;
+}
+
+/*
+ * Return accounted runtime for the task.
+ * In case the task is currently running, return the runtime plus current's
+ * pending runtime that have not been accounted yet.
+ */
+unsigned long long task_sched_runtime(struct task_struct *p)
+{
+	unsigned long flags;
+	struct rq *rq;
+	u64 ns = 0;
+
+	rq = task_rq_lock(p, &flags);
+	ns = p->se.sum_exec_runtime + do_task_delta_exec(p, rq);
+	task_rq_unlock(rq, p, &flags);
+
+	return ns;
+}
+
+#ifdef CONFIG_CGROUP_CPUACCT
+struct cgroup_subsys cpuacct_subsys;
+struct cpuacct root_cpuacct;
+#endif
+
+static inline void task_group_account_field(struct task_struct *p, int index,
+					    u64 tmp)
+{
+#ifdef CONFIG_CGROUP_CPUACCT
+	struct kernel_cpustat *kcpustat;
+	struct cpuacct *ca;
+#endif
+	/*
+	 * Since all updates are sure to touch the root cgroup, we
+	 * get ourselves ahead and touch it first. If the root cgroup
+	 * is the only cgroup, then nothing else should be necessary.
+	 *
+	 */
+	__get_cpu_var(kernel_cpustat).cpustat[index] += tmp;
+
+#ifdef CONFIG_CGROUP_CPUACCT
+	if (unlikely(!cpuacct_subsys.active))
+		return;
+
+	rcu_read_lock();
+	ca = task_ca(p);
+	while (ca && (ca != &root_cpuacct)) {
+		kcpustat = this_cpu_ptr(ca->cpustat);
+		kcpustat->cpustat[index] += tmp;
+		ca = parent_ca(ca);
+	}
+	rcu_read_unlock();
+#endif
+}
+
+
+/*
+ * Account user cpu time to a process.
+ * @p: the process that the cpu time gets accounted to
+ * @cputime: the cpu time spent in user space since the last update
+ * @cputime_scaled: cputime scaled by cpu frequency
+ */
+void account_user_time(struct task_struct *p, cputime_t cputime,
+		       cputime_t cputime_scaled)
+{
+	int index;
+
+	/* Add user time to process. */
+	p->utime += cputime;
+	p->utimescaled += cputime_scaled;
+	account_group_user_time(p, cputime);
+
+	index = (TASK_NICE(p) > 0) ? CPUTIME_NICE : CPUTIME_USER;
+
+	/* Add user time to cpustat. */
+	task_group_account_field(p, index, (__force u64) cputime);
+
+	/* Account for user time used */
+	acct_update_integrals(p);
+}
+
+/*
+ * Account guest cpu time to a process.
+ * @p: the process that the cpu time gets accounted to
+ * @cputime: the cpu time spent in virtual machine since the last update
+ * @cputime_scaled: cputime scaled by cpu frequency
+ */
+static void account_guest_time(struct task_struct *p, cputime_t cputime,
+			       cputime_t cputime_scaled)
+{
+	u64 *cpustat = kcpustat_this_cpu->cpustat;
+
+	/* Add guest time to process. */
+	p->utime += cputime;
+	p->utimescaled += cputime_scaled;
+	account_group_user_time(p, cputime);
+	p->gtime += cputime;
+
+	/* Add guest time to cpustat. */
+	if (TASK_NICE(p) > 0) {
+		cpustat[CPUTIME_NICE] += (__force u64) cputime;
+		cpustat[CPUTIME_GUEST_NICE] += (__force u64) cputime;
+	} else {
+		cpustat[CPUTIME_USER] += (__force u64) cputime;
+		cpustat[CPUTIME_GUEST] += (__force u64) cputime;
+	}
+}
+
+/*
+ * Account system cpu time to a process and desired cpustat field
+ * @p: the process that the cpu time gets accounted to
+ * @cputime: the cpu time spent in kernel space since the last update
+ * @cputime_scaled: cputime scaled by cpu frequency
+ * @target_cputime64: pointer to cpustat field that has to be updated
+ */
+static inline
+void __account_system_time(struct task_struct *p, cputime_t cputime,
+			cputime_t cputime_scaled, int index)
+{
+	/* Add system time to process. */
+	p->stime += cputime;
+	p->stimescaled += cputime_scaled;
+	account_group_system_time(p, cputime);
+
+	/* Add system time to cpustat. */
+	task_group_account_field(p, index, (__force u64) cputime);
+
+	/* Account for system time used */
+	acct_update_integrals(p);
+}
+
+/*
+ * Account system cpu time to a process.
+ * @p: the process that the cpu time gets accounted to
+ * @hardirq_offset: the offset to subtract from hardirq_count()
+ * @cputime: the cpu time spent in kernel space since the last update
+ * @cputime_scaled: cputime scaled by cpu frequency
+ */
+void account_system_time(struct task_struct *p, int hardirq_offset,
+			 cputime_t cputime, cputime_t cputime_scaled)
+{
+	int index;
+
+	if ((p->flags & PF_VCPU) && (irq_count() - hardirq_offset == 0)) {
+		account_guest_time(p, cputime, cputime_scaled);
+		return;
+	}
+
+	if (hardirq_count() - hardirq_offset)
+		index = CPUTIME_IRQ;
+	else if (in_serving_softirq())
+		index = CPUTIME_SOFTIRQ;
+	else
+		index = CPUTIME_SYSTEM;
+
+	__account_system_time(p, cputime, cputime_scaled, index);
+}
+
+/*
+ * Account for involuntary wait time.
+ * @cputime: the cpu time spent in involuntary wait
+ */
+void account_steal_time(cputime_t cputime)
+{
+	u64 *cpustat = kcpustat_this_cpu->cpustat;
+
+	cpustat[CPUTIME_STEAL] += (__force u64) cputime;
+}
+
+/*
+ * Account for idle time.
+ * @cputime: the cpu time spent in idle wait
+ */
+void account_idle_time(cputime_t cputime)
+{
+	u64 *cpustat = kcpustat_this_cpu->cpustat;
+	struct rq *rq = this_rq();
+
+	if (atomic_read(&rq->nr_iowait) > 0)
+		cpustat[CPUTIME_IOWAIT] += (__force u64) cputime;
+	else
+		cpustat[CPUTIME_IDLE] += (__force u64) cputime;
+}
+
+static __always_inline bool steal_account_process_tick(void)
+{
+#ifdef CONFIG_PARAVIRT
+	if (static_branch(&paravirt_steal_enabled)) {
+		u64 steal, st = 0;
+
+		steal = paravirt_steal_clock(smp_processor_id());
+		steal -= this_rq()->prev_steal_time;
+
+		st = steal_ticks(steal);
+		this_rq()->prev_steal_time += st * TICK_NSEC;
+
+		account_steal_time(st);
+		return st;
+	}
+#endif
+	return false;
+}
+
+#ifndef CONFIG_VIRT_CPU_ACCOUNTING
+
+#ifdef CONFIG_IRQ_TIME_ACCOUNTING
+/*
+ * Account a tick to a process and cpustat
+ * @p: the process that the cpu time gets accounted to
+ * @user_tick: is the tick from userspace
+ * @rq: the pointer to rq
+ *
+ * Tick demultiplexing follows the order
+ * - pending hardirq update
+ * - pending softirq update
+ * - user_time
+ * - idle_time
+ * - system time
+ *   - check for guest_time
+ *   - else account as system_time
+ *
+ * Check for hardirq is done both for system and user time as there is
+ * no timer going off while we are on hardirq and hence we may never get an
+ * opportunity to update it solely in system time.
+ * p->stime and friends are only updated on system time and not on irq
+ * softirq as those do not count in task exec_runtime any more.
+ */
+static void irqtime_account_process_tick(struct task_struct *p, int user_tick,
+						struct rq *rq)
+{
+	cputime_t one_jiffy_scaled = cputime_to_scaled(cputime_one_jiffy);
+	u64 *cpustat = kcpustat_this_cpu->cpustat;
+
+	if (steal_account_process_tick())
+		return;
+
+	if (irqtime_account_hi_update()) {
+		cpustat[CPUTIME_IRQ] += (__force u64) cputime_one_jiffy;
+	} else if (irqtime_account_si_update()) {
+		cpustat[CPUTIME_SOFTIRQ] += (__force u64) cputime_one_jiffy;
+	} else if (this_cpu_ksoftirqd() == p) {
+		/*
+		 * ksoftirqd time do not get accounted in cpu_softirq_time.
+		 * So, we have to handle it separately here.
+		 * Also, p->stime needs to be updated for ksoftirqd.
+		 */
+		__account_system_time(p, cputime_one_jiffy, one_jiffy_scaled,
+					CPUTIME_SOFTIRQ);
+	} else if (user_tick) {
+		account_user_time(p, cputime_one_jiffy, one_jiffy_scaled);
+	} else if (p == rq->idle) {
+		account_idle_time(cputime_one_jiffy);
+	} else if (p->flags & PF_VCPU) { /* System time or guest time */
+		account_guest_time(p, cputime_one_jiffy, one_jiffy_scaled);
+	} else {
+		__account_system_time(p, cputime_one_jiffy, one_jiffy_scaled,
+					CPUTIME_SYSTEM);
+	}
+}
+
+static void irqtime_account_idle_ticks(int ticks)
+{
+	int i;
+	struct rq *rq = this_rq();
+
+	for (i = 0; i < ticks; i++)
+		irqtime_account_process_tick(current, 0, rq);
+}
+#else /* CONFIG_IRQ_TIME_ACCOUNTING */
+static void irqtime_account_idle_ticks(int ticks) {}
+static void irqtime_account_process_tick(struct task_struct *p, int user_tick,
+						struct rq *rq) {}
+#endif /* CONFIG_IRQ_TIME_ACCOUNTING */
+
+/*
+ * Account a single tick of cpu time.
+ * @p: the process that the cpu time gets accounted to
+ * @user_tick: indicates if the tick is a user or a system tick
+ */
+void account_process_tick(struct task_struct *p, int user_tick)
+{
+	cputime_t one_jiffy_scaled = cputime_to_scaled(cputime_one_jiffy);
+	struct rq *rq = this_rq();
+
+	if (sched_clock_irqtime) {
+		irqtime_account_process_tick(p, user_tick, rq);
+		return;
+	}
+
+	if (steal_account_process_tick())
+		return;
+
+	if (user_tick)
+		account_user_time(p, cputime_one_jiffy, one_jiffy_scaled);
+	else if ((p != rq->idle) || (irq_count() != HARDIRQ_OFFSET))
+		account_system_time(p, HARDIRQ_OFFSET, cputime_one_jiffy,
+				    one_jiffy_scaled);
+	else
+		account_idle_time(cputime_one_jiffy);
+}
+
+/*
+ * Account multiple ticks of steal time.
+ * @p: the process from which the cpu time has been stolen
+ * @ticks: number of stolen ticks
+ */
+void account_steal_ticks(unsigned long ticks)
+{
+	account_steal_time(jiffies_to_cputime(ticks));
+}
+
+/*
+ * Account multiple ticks of idle time.
+ * @ticks: number of stolen ticks
+ */
+void account_idle_ticks(unsigned long ticks)
+{
+
+	if (sched_clock_irqtime) {
+		irqtime_account_idle_ticks(ticks);
+		return;
+	}
+
+	account_idle_time(jiffies_to_cputime(ticks));
+}
+
+#endif
+
+/*
+ * Use precise platform statistics if available:
+ */
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING
+void task_times(struct task_struct *p, cputime_t *ut, cputime_t *st)
+{
+	*ut = p->utime;
+	*st = p->stime;
+}
+
+void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st)
+{
+	struct task_cputime cputime;
+
+	thread_group_cputime(p, &cputime);
+
+	*ut = cputime.utime;
+	*st = cputime.stime;
+}
+#else
+
+#ifndef nsecs_to_cputime
+# define nsecs_to_cputime(__nsecs)	nsecs_to_jiffies(__nsecs)
+#endif
+
+void task_times(struct task_struct *p, cputime_t *ut, cputime_t *st)
+{
+	cputime_t rtime, utime = p->utime, total = utime + p->stime;
+
+	/*
+	 * Use CFS's precise accounting:
+	 */
+	rtime = nsecs_to_cputime(p->se.sum_exec_runtime);
+
+	if (total) {
+		u64 temp = (__force u64) rtime;
+
+		temp *= (__force u64) utime;
+		do_div(temp, (__force u32) total);
+		utime = (__force cputime_t) temp;
+	} else
+		utime = rtime;
+
+	/*
+	 * Compare with previous values, to keep monotonicity:
+	 */
+	p->prev_utime = max(p->prev_utime, utime);
+	p->prev_stime = max(p->prev_stime, rtime - p->prev_utime);
+
+	*ut = p->prev_utime;
+	*st = p->prev_stime;
+}
+
+/*
+ * Must be called with siglock held.
+ */
+void thread_group_times(struct task_struct *p, cputime_t *ut, cputime_t *st)
+{
+	struct signal_struct *sig = p->signal;
+	struct task_cputime cputime;
+	cputime_t rtime, utime, total;
+
+	thread_group_cputime(p, &cputime);
+
+	total = cputime.utime + cputime.stime;
+	rtime = nsecs_to_cputime(cputime.sum_exec_runtime);
+
+	if (total) {
+		u64 temp = (__force u64) rtime;
+
+		temp *= (__force u64) cputime.utime;
+		do_div(temp, (__force u32) total);
+		utime = (__force cputime_t) temp;
+	} else
+		utime = rtime;
+
+	sig->prev_utime = max(sig->prev_utime, utime);
+	sig->prev_stime = max(sig->prev_stime, rtime - sig->prev_utime);
+
+	*ut = sig->prev_utime;
+	*st = sig->prev_stime;
+}
+#endif
+
+/*
+ * This function gets called by the timer code, with HZ frequency.
+ * We call it with interrupts disabled.
+ */
+void scheduler_tick(void)
+{
+	int cpu = smp_processor_id();
+	struct rq *rq = cpu_rq(cpu);
+	struct task_struct *curr = rq->curr;
+
+	sched_clock_tick();
+
+	raw_spin_lock(&rq->lock);
+	update_rq_clock(rq);
+	update_cpu_load_active(rq);
+	curr->sched_class->task_tick(rq, curr, 0);
+	raw_spin_unlock(&rq->lock);
+
+	perf_event_task_tick();
+
+#ifdef CONFIG_SMP
+	rq->idle_balance = idle_cpu(cpu);
+	trigger_load_balance(rq, cpu);
+#endif
+}
+
+notrace unsigned long get_parent_ip(unsigned long addr)
+{
+	if (in_lock_functions(addr)) {
+		addr = CALLER_ADDR2;
+		if (in_lock_functions(addr))
+			addr = CALLER_ADDR3;
+	}
+	return addr;
+}
+
+#if defined(CONFIG_PREEMPT) && (defined(CONFIG_DEBUG_PREEMPT) || \
+				defined(CONFIG_PREEMPT_TRACER))
+
+void __kprobes add_preempt_count(int val)
+{
+#ifdef CONFIG_DEBUG_PREEMPT
+	/*
+	 * Underflow?
+	 */
+	if (DEBUG_LOCKS_WARN_ON((preempt_count() < 0)))
+		return;
+#endif
+	preempt_count() += val;
+#ifdef CONFIG_DEBUG_PREEMPT
+	/*
+	 * Spinlock count overflowing soon?
+	 */
+	DEBUG_LOCKS_WARN_ON((preempt_count() & PREEMPT_MASK) >=
+				PREEMPT_MASK - 10);
+#endif
+	if (preempt_count() == val)
+		trace_preempt_off(CALLER_ADDR0, get_parent_ip(CALLER_ADDR1));
+}
+EXPORT_SYMBOL(add_preempt_count);
+
+void __kprobes sub_preempt_count(int val)
+{
+#ifdef CONFIG_DEBUG_PREEMPT
+	/*
+	 * Underflow?
+	 */
+	if (DEBUG_LOCKS_WARN_ON(val > preempt_count()))
+		return;
+	/*
+	 * Is the spinlock portion underflowing?
+	 */
+	if (DEBUG_LOCKS_WARN_ON((val < PREEMPT_MASK) &&
+			!(preempt_count() & PREEMPT_MASK)))
+		return;
+#endif
+
+	if (preempt_count() == val)
+		trace_preempt_on(CALLER_ADDR0, get_parent_ip(CALLER_ADDR1));
+	preempt_count() -= val;
+}
+EXPORT_SYMBOL(sub_preempt_count);
+
+#endif
+
+/*
+ * Print scheduling while atomic bug:
+ */
+static noinline void __schedule_bug(struct task_struct *prev)
+{
+	struct pt_regs *regs = get_irq_regs();
+
+	if (oops_in_progress)
+		return;
+
+	printk(KERN_ERR "BUG: scheduling while atomic: %s/%d/0x%08x\n",
+		prev->comm, prev->pid, preempt_count());
+
+	debug_show_held_locks(prev);
+	print_modules();
+	if (irqs_disabled())
+		print_irqtrace_events(prev);
+
+	if (regs)
+		show_regs(regs);
+	else
+		dump_stack();
+}
+
+/*
+ * Various schedule()-time debugging checks and statistics:
+ */
+static inline void schedule_debug(struct task_struct *prev)
+{
+	/*
+	 * Test if we are atomic. Since do_exit() needs to call into
+	 * schedule() atomically, we ignore that path for now.
+	 * Otherwise, whine if we are scheduling when we should not be.
+	 */
+	if (unlikely(in_atomic_preempt_off() && !prev->exit_state))
+		__schedule_bug(prev);
+	rcu_sleep_check();
+
+	profile_hit(SCHED_PROFILING, __builtin_return_address(0));
+
+	schedstat_inc(this_rq(), sched_count);
+}
+
+static void put_prev_task(struct rq *rq, struct task_struct *prev)
+{
+	if (prev->on_rq || rq->skip_clock_update < 0)
+		update_rq_clock(rq);
+	prev->sched_class->put_prev_task(rq, prev);
+}
+
+/*
+ * Pick up the highest-prio task:
+ */
+static inline struct task_struct *
+pick_next_task(struct rq *rq)
+{
+	const struct sched_class *class;
+	struct task_struct *p;
+
+	/*
+	 * Optimization: we know that if all tasks are in
+	 * the fair class we can call that function directly:
+	 */
+	if (likely(rq->nr_running == rq->cfs.h_nr_running)) {
+		p = fair_sched_class.pick_next_task(rq);
+		if (likely(p))
+			return p;
+	}
+
+	for_each_class(class) {
+		p = class->pick_next_task(rq);
+		if (p)
+			return p;
+	}
+
+	BUG(); /* the idle class will always have a runnable task */
+}
+
+/*
+ * __schedule() is the main scheduler function.
+ */
+static void __sched __schedule(void)
+{
+	struct task_struct *prev, *next;
+	unsigned long *switch_count;
+	struct rq *rq;
+	int cpu;
+
+need_resched:
+	preempt_disable();
+	cpu = smp_processor_id();
+	rq = cpu_rq(cpu);
+	rcu_note_context_switch(cpu);
+	prev = rq->curr;
+
+	schedule_debug(prev);
+
+	if (sched_feat(HRTICK))
+		hrtick_clear(rq);
+
+	raw_spin_lock_irq(&rq->lock);
+
+	switch_count = &prev->nivcsw;
+	if (prev->state && !(preempt_count() & PREEMPT_ACTIVE)) {
+		if (unlikely(signal_pending_state(prev->state, prev))) {
+			prev->state = TASK_RUNNING;
+		} else {
+			deactivate_task(rq, prev, DEQUEUE_SLEEP);
+			prev->on_rq = 0;
+
+			/*
+			 * If a worker went to sleep, notify and ask workqueue
+			 * whether it wants to wake up a task to maintain
+			 * concurrency.
+			 */
+			if (prev->flags & PF_WQ_WORKER) {
+				struct task_struct *to_wakeup;
+
+				to_wakeup = wq_worker_sleeping(prev, cpu);
+				if (to_wakeup)
+					try_to_wake_up_local(to_wakeup);
+			}
+		}
+		switch_count = &prev->nvcsw;
+	}
+
+	pre_schedule(rq, prev);
+
+	if (unlikely(!rq->nr_running))
+		idle_balance(cpu, rq);
+
+	put_prev_task(rq, prev);
+	next = pick_next_task(rq);
+	clear_tsk_need_resched(prev);
+	rq->skip_clock_update = 0;
+
+	if (likely(prev != next)) {
+		rq->nr_switches++;
+		rq->curr = next;
+		++*switch_count;
+
+		context_switch(rq, prev, next); /* unlocks the rq */
+		/*
+		 * The context switch have flipped the stack from under us
+		 * and restored the local variables which were saved when
+		 * this task called schedule() in the past. prev == current
+		 * is still correct, but it can be moved to another cpu/rq.
+		 */
+		cpu = smp_processor_id();
+		rq = cpu_rq(cpu);
+	} else
+		raw_spin_unlock_irq(&rq->lock);
+
+	post_schedule(rq);
+
+	preempt_enable_no_resched();
+	if (need_resched())
+		goto need_resched;
+}
+
+static inline void sched_submit_work(struct task_struct *tsk)
+{
+	if (!tsk->state)
+		return;
+	/*
+	 * If we are going to sleep and we have plugged IO queued,
+	 * make sure to submit it to avoid deadlocks.
+	 */
+	if (blk_needs_flush_plug(tsk))
+		blk_schedule_flush_plug(tsk);
+}
+
+asmlinkage void __sched schedule(void)
+{
+	struct task_struct *tsk = current;
+
+	sched_submit_work(tsk);
+	__schedule();
+}
+EXPORT_SYMBOL(schedule);
+
+#ifdef CONFIG_MUTEX_SPIN_ON_OWNER
+
+static inline bool owner_running(struct mutex *lock, struct task_struct *owner)
+{
+	if (lock->owner != owner)
+		return false;
+
+	/*
+	 * Ensure we emit the owner->on_cpu, dereference _after_ checking
+	 * lock->owner still matches owner, if that fails, owner might
+	 * point to free()d memory, if it still matches, the rcu_read_lock()
+	 * ensures the memory stays valid.
+	 */
+	barrier();
+
+	return owner->on_cpu;
+}
+
+/*
+ * Look out! "owner" is an entirely speculative pointer
+ * access and not reliable.
+ */
+int mutex_spin_on_owner(struct mutex *lock, struct task_struct *owner)
+{
+	if (!sched_feat(OWNER_SPIN))
+		return 0;
+
+	rcu_read_lock();
+	while (owner_running(lock, owner)) {
+		if (need_resched())
+			break;
+
+		arch_mutex_cpu_relax();
+	}
+	rcu_read_unlock();
+
+	/*
+	 * We break out the loop above on need_resched() and when the
+	 * owner changed, which is a sign for heavy contention. Return
+	 * success only when lock->owner is NULL.
+	 */
+	return lock->owner == NULL;
+}
+#endif
+
+#ifdef CONFIG_PREEMPT
+/*
+ * this is the entry point to schedule() from in-kernel preemption
+ * off of preempt_enable. Kernel preemptions off return from interrupt
+ * occur there and call schedule directly.
+ */
+asmlinkage void __sched notrace preempt_schedule(void)
+{
+	struct thread_info *ti = current_thread_info();
+
+	/*
+	 * If there is a non-zero preempt_count or interrupts are disabled,
+	 * we do not want to preempt the current task. Just return..
+	 */
+	if (likely(ti->preempt_count || irqs_disabled()))
+		return;
+
+	do {
+		add_preempt_count_notrace(PREEMPT_ACTIVE);
+		__schedule();
+		sub_preempt_count_notrace(PREEMPT_ACTIVE);
+
+		/*
+		 * Check again in case we missed a preemption opportunity
+		 * between schedule and now.
+		 */
+		barrier();
+	} while (need_resched());
+}
+EXPORT_SYMBOL(preempt_schedule);
+
+/*
+ * this is the entry point to schedule() from kernel preemption
+ * off of irq context.
+ * Note, that this is called and return with irqs disabled. This will
+ * protect us against recursive calling from irq.
+ */
+asmlinkage void __sched preempt_schedule_irq(void)
+{
+	struct thread_info *ti = current_thread_info();
+
+	/* Catch callers which need to be fixed */
+	BUG_ON(ti->preempt_count || !irqs_disabled());
+
+	do {
+		add_preempt_count(PREEMPT_ACTIVE);
+		local_irq_enable();
+		__schedule();
+		local_irq_disable();
+		sub_preempt_count(PREEMPT_ACTIVE);
+
+		/*
+		 * Check again in case we missed a preemption opportunity
+		 * between schedule and now.
+		 */
+		barrier();
+	} while (need_resched());
+}
+
+#endif /* CONFIG_PREEMPT */
+
+int default_wake_function(wait_queue_t *curr, unsigned mode, int wake_flags,
+			  void *key)
+{
+	return try_to_wake_up(curr->private, mode, wake_flags);
+}
+EXPORT_SYMBOL(default_wake_function);
+
+/*
+ * The core wakeup function. Non-exclusive wakeups (nr_exclusive == 0) just
+ * wake everything up. If it's an exclusive wakeup (nr_exclusive == small +ve
+ * number) then we wake all the non-exclusive tasks and one exclusive task.
+ *
+ * There are circumstances in which we can try to wake a task which has already
+ * started to run but is not in state TASK_RUNNING. try_to_wake_up() returns
+ * zero in this (rare) case, and we handle it by continuing to scan the queue.
+ */
+static void __wake_up_common(wait_queue_head_t *q, unsigned int mode,
+			int nr_exclusive, int wake_flags, void *key)
+{
+	wait_queue_t *curr, *next;
+
+	list_for_each_entry_safe(curr, next, &q->task_list, task_list) {
+		unsigned flags = curr->flags;
+
+		if (curr->func(curr, mode, wake_flags, key) &&
+				(flags & WQ_FLAG_EXCLUSIVE) && !--nr_exclusive)
+			break;
+	}
+}
+
+/**
+ * __wake_up - wake up threads blocked on a waitqueue.
+ * @q: the waitqueue
+ * @mode: which threads
+ * @nr_exclusive: how many wake-one or wake-many threads to wake up
+ * @key: is directly passed to the wakeup function
+ *
+ * It may be assumed that this function implies a write memory barrier before
+ * changing the task state if and only if any tasks are woken up.
+ */
+void __wake_up(wait_queue_head_t *q, unsigned int mode,
+			int nr_exclusive, void *key)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&q->lock, flags);
+	__wake_up_common(q, mode, nr_exclusive, 0, key);
+	spin_unlock_irqrestore(&q->lock, flags);
+}
+EXPORT_SYMBOL(__wake_up);
+
+/*
+ * Same as __wake_up but called with the spinlock in wait_queue_head_t held.
+ */
+void __wake_up_locked(wait_queue_head_t *q, unsigned int mode)
+{
+	__wake_up_common(q, mode, 1, 0, NULL);
+}
+EXPORT_SYMBOL_GPL(__wake_up_locked);
+
+void __wake_up_locked_key(wait_queue_head_t *q, unsigned int mode, void *key)
+{
+	__wake_up_common(q, mode, 1, 0, key);
+}
+EXPORT_SYMBOL_GPL(__wake_up_locked_key);
+
+/**
+ * __wake_up_sync_key - wake up threads blocked on a waitqueue.
+ * @q: the waitqueue
+ * @mode: which threads
+ * @nr_exclusive: how many wake-one or wake-many threads to wake up
+ * @key: opaque value to be passed to wakeup targets
+ *
+ * The sync wakeup differs that the waker knows that it will schedule
+ * away soon, so while the target thread will be woken up, it will not
+ * be migrated to another CPU - ie. the two threads are 'synchronized'
+ * with each other. This can prevent needless bouncing between CPUs.
+ *
+ * On UP it can prevent extra preemption.
+ *
+ * It may be assumed that this function implies a write memory barrier before
+ * changing the task state if and only if any tasks are woken up.
+ */
+void __wake_up_sync_key(wait_queue_head_t *q, unsigned int mode,
+			int nr_exclusive, void *key)
+{
+	unsigned long flags;
+	int wake_flags = WF_SYNC;
+
+	if (unlikely(!q))
+		return;
+
+	if (unlikely(!nr_exclusive))
+		wake_flags = 0;
+
+	spin_lock_irqsave(&q->lock, flags);
+	__wake_up_common(q, mode, nr_exclusive, wake_flags, key);
+	spin_unlock_irqrestore(&q->lock, flags);
+}
+EXPORT_SYMBOL_GPL(__wake_up_sync_key);
+
+/*
+ * __wake_up_sync - see __wake_up_sync_key()
+ */
+void __wake_up_sync(wait_queue_head_t *q, unsigned int mode, int nr_exclusive)
+{
+	__wake_up_sync_key(q, mode, nr_exclusive, NULL);
+}
+EXPORT_SYMBOL_GPL(__wake_up_sync);	/* For internal use only */
+
+/**
+ * complete: - signals a single thread waiting on this completion
+ * @x:  holds the state of this particular completion
+ *
+ * This will wake up a single thread waiting on this completion. Threads will be
+ * awakened in the same order in which they were queued.
+ *
+ * See also complete_all(), wait_for_completion() and related routines.
+ *
+ * It may be assumed that this function implies a write memory barrier before
+ * changing the task state if and only if any tasks are woken up.
+ */
+void complete(struct completion *x)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&x->wait.lock, flags);
+	x->done++;
+	__wake_up_common(&x->wait, TASK_NORMAL, 1, 0, NULL);
+	spin_unlock_irqrestore(&x->wait.lock, flags);
+}
+EXPORT_SYMBOL(complete);
+
+/**
+ * complete_all: - signals all threads waiting on this completion
+ * @x:  holds the state of this particular completion
+ *
+ * This will wake up all threads waiting on this particular completion event.
+ *
+ * It may be assumed that this function implies a write memory barrier before
+ * changing the task state if and only if any tasks are woken up.
+ */
+void complete_all(struct completion *x)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&x->wait.lock, flags);
+	x->done += UINT_MAX/2;
+	__wake_up_common(&x->wait, TASK_NORMAL, 0, 0, NULL);
+	spin_unlock_irqrestore(&x->wait.lock, flags);
+}
+EXPORT_SYMBOL(complete_all);
+
+static inline long __sched
+do_wait_for_common(struct completion *x, long timeout, int state)
+{
+	if (!x->done) {
+		DECLARE_WAITQUEUE(wait, current);
+
+		__add_wait_queue_tail_exclusive(&x->wait, &wait);
+		do {
+			if (signal_pending_state(state, current)) {
+				timeout = -ERESTARTSYS;
+				break;
+			}
+			__set_current_state(state);
+			spin_unlock_irq(&x->wait.lock);
+			timeout = schedule_timeout(timeout);
+			spin_lock_irq(&x->wait.lock);
+		} while (!x->done && timeout);
+		__remove_wait_queue(&x->wait, &wait);
+		if (!x->done)
+			return timeout;
+	}
+	x->done--;
+	return timeout ?: 1;
+}
+
+static long __sched
+wait_for_common(struct completion *x, long timeout, int state)
+{
+	might_sleep();
+
+	spin_lock_irq(&x->wait.lock);
+	timeout = do_wait_for_common(x, timeout, state);
+	spin_unlock_irq(&x->wait.lock);
+	return timeout;
+}
+
+/**
+ * wait_for_completion: - waits for completion of a task
+ * @x:  holds the state of this particular completion
+ *
+ * This waits to be signaled for completion of a specific task. It is NOT
+ * interruptible and there is no timeout.
+ *
+ * See also similar routines (i.e. wait_for_completion_timeout()) with timeout
+ * and interrupt capability. Also see complete().
+ */
+void __sched wait_for_completion(struct completion *x)
+{
+	wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_UNINTERRUPTIBLE);
+}
+EXPORT_SYMBOL(wait_for_completion);
+
+/**
+ * wait_for_completion_timeout: - waits for completion of a task (w/timeout)
+ * @x:  holds the state of this particular completion
+ * @timeout:  timeout value in jiffies
+ *
+ * This waits for either a completion of a specific task to be signaled or for a
+ * specified timeout to expire. The timeout is in jiffies. It is not
+ * interruptible.
+ *
+ * The return value is 0 if timed out, and positive (at least 1, or number of
+ * jiffies left till timeout) if completed.
+ */
+unsigned long __sched
+wait_for_completion_timeout(struct completion *x, unsigned long timeout)
+{
+	return wait_for_common(x, timeout, TASK_UNINTERRUPTIBLE);
+}
+EXPORT_SYMBOL(wait_for_completion_timeout);
+
+/**
+ * wait_for_completion_interruptible: - waits for completion of a task (w/intr)
+ * @x:  holds the state of this particular completion
+ *
+ * This waits for completion of a specific task to be signaled. It is
+ * interruptible.
+ *
+ * The return value is -ERESTARTSYS if interrupted, 0 if completed.
+ */
+int __sched wait_for_completion_interruptible(struct completion *x)
+{
+	long t = wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_INTERRUPTIBLE);
+	if (t == -ERESTARTSYS)
+		return t;
+	return 0;
+}
+EXPORT_SYMBOL(wait_for_completion_interruptible);
+
+/**
+ * wait_for_completion_interruptible_timeout: - waits for completion (w/(to,intr))
+ * @x:  holds the state of this particular completion
+ * @timeout:  timeout value in jiffies
+ *
+ * This waits for either a completion of a specific task to be signaled or for a
+ * specified timeout to expire. It is interruptible. The timeout is in jiffies.
+ *
+ * The return value is -ERESTARTSYS if interrupted, 0 if timed out,
+ * positive (at least 1, or number of jiffies left till timeout) if completed.
+ */
+long __sched
+wait_for_completion_interruptible_timeout(struct completion *x,
+					  unsigned long timeout)
+{
+	return wait_for_common(x, timeout, TASK_INTERRUPTIBLE);
+}
+EXPORT_SYMBOL(wait_for_completion_interruptible_timeout);
+
+/**
+ * wait_for_completion_killable: - waits for completion of a task (killable)
+ * @x:  holds the state of this particular completion
+ *
+ * This waits to be signaled for completion of a specific task. It can be
+ * interrupted by a kill signal.
+ *
+ * The return value is -ERESTARTSYS if interrupted, 0 if completed.
+ */
+int __sched wait_for_completion_killable(struct completion *x)
+{
+	long t = wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_KILLABLE);
+	if (t == -ERESTARTSYS)
+		return t;
+	return 0;
+}
+EXPORT_SYMBOL(wait_for_completion_killable);
+
+/**
+ * wait_for_completion_killable_timeout: - waits for completion of a task (w/(to,killable))
+ * @x:  holds the state of this particular completion
+ * @timeout:  timeout value in jiffies
+ *
+ * This waits for either a completion of a specific task to be
+ * signaled or for a specified timeout to expire. It can be
+ * interrupted by a kill signal. The timeout is in jiffies.
+ *
+ * The return value is -ERESTARTSYS if interrupted, 0 if timed out,
+ * positive (at least 1, or number of jiffies left till timeout) if completed.
+ */
+long __sched
+wait_for_completion_killable_timeout(struct completion *x,
+				     unsigned long timeout)
+{
+	return wait_for_common(x, timeout, TASK_KILLABLE);
+}
+EXPORT_SYMBOL(wait_for_completion_killable_timeout);
+
+/**
+ *	try_wait_for_completion - try to decrement a completion without blocking
+ *	@x:	completion structure
+ *
+ *	Returns: 0 if a decrement cannot be done without blocking
+ *		 1 if a decrement succeeded.
+ *
+ *	If a completion is being used as a counting completion,
+ *	attempt to decrement the counter without blocking. This
+ *	enables us to avoid waiting if the resource the completion
+ *	is protecting is not available.
+ */
+bool try_wait_for_completion(struct completion *x)
+{
+	unsigned long flags;
+	int ret = 1;
+
+	spin_lock_irqsave(&x->wait.lock, flags);
+	if (!x->done)
+		ret = 0;
+	else
+		x->done--;
+	spin_unlock_irqrestore(&x->wait.lock, flags);
+	return ret;
+}
+EXPORT_SYMBOL(try_wait_for_completion);
+
+/**
+ *	completion_done - Test to see if a completion has any waiters
+ *	@x:	completion structure
+ *
+ *	Returns: 0 if there are waiters (wait_for_completion() in progress)
+ *		 1 if there are no waiters.
+ *
+ */
+bool completion_done(struct completion *x)
+{
+	unsigned long flags;
+	int ret = 1;
+
+	spin_lock_irqsave(&x->wait.lock, flags);
+	if (!x->done)
+		ret = 0;
+	spin_unlock_irqrestore(&x->wait.lock, flags);
+	return ret;
+}
+EXPORT_SYMBOL(completion_done);
+
+static long __sched
+sleep_on_common(wait_queue_head_t *q, int state, long timeout)
+{
+	unsigned long flags;
+	wait_queue_t wait;
+
+	init_waitqueue_entry(&wait, current);
+
+	__set_current_state(state);
+
+	spin_lock_irqsave(&q->lock, flags);
+	__add_wait_queue(q, &wait);
+	spin_unlock(&q->lock);
+	timeout = schedule_timeout(timeout);
+	spin_lock_irq(&q->lock);
+	__remove_wait_queue(q, &wait);
+	spin_unlock_irqrestore(&q->lock, flags);
+
+	return timeout;
+}
+
+void __sched interruptible_sleep_on(wait_queue_head_t *q)
+{
+	sleep_on_common(q, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
+}
+EXPORT_SYMBOL(interruptible_sleep_on);
+
+long __sched
+interruptible_sleep_on_timeout(wait_queue_head_t *q, long timeout)
+{
+	return sleep_on_common(q, TASK_INTERRUPTIBLE, timeout);
+}
+EXPORT_SYMBOL(interruptible_sleep_on_timeout);
+
+void __sched sleep_on(wait_queue_head_t *q)
+{
+	sleep_on_common(q, TASK_UNINTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
+}
+EXPORT_SYMBOL(sleep_on);
+
+long __sched sleep_on_timeout(wait_queue_head_t *q, long timeout)
+{
+	return sleep_on_common(q, TASK_UNINTERRUPTIBLE, timeout);
+}
+EXPORT_SYMBOL(sleep_on_timeout);
+
+#ifdef CONFIG_RT_MUTEXES
+
+/*
+ * rt_mutex_setprio - set the current priority of a task
+ * @p: task
+ * @prio: prio value (kernel-internal form)
+ *
+ * This function changes the 'effective' priority of a task. It does
+ * not touch ->normal_prio like __setscheduler().
+ *
+ * Used by the rt_mutex code to implement priority inheritance logic.
+ */
+void rt_mutex_setprio(struct task_struct *p, int prio)
+{
+	int oldprio, on_rq, running;
+	struct rq *rq;
+	const struct sched_class *prev_class;
+
+	BUG_ON(prio < 0 || prio > MAX_PRIO);
+
+	rq = __task_rq_lock(p);
+
+	trace_sched_pi_setprio(p, prio);
+	oldprio = p->prio;
+	prev_class = p->sched_class;
+	on_rq = p->on_rq;
+	running = task_current(rq, p);
+	if (on_rq)
+		dequeue_task(rq, p, 0);
+	if (running)
+		p->sched_class->put_prev_task(rq, p);
+
+	if (rt_prio(prio))
+		p->sched_class = &rt_sched_class;
+	else
+		p->sched_class = &fair_sched_class;
+
+	p->prio = prio;
+
+	if (running)
+		p->sched_class->set_curr_task(rq);
+	if (on_rq)
+		enqueue_task(rq, p, oldprio < prio ? ENQUEUE_HEAD : 0);
+
+	check_class_changed(rq, p, prev_class, oldprio);
+	__task_rq_unlock(rq);
+}
+
+#endif
+
+void set_user_nice(struct task_struct *p, long nice)
+{
+	int old_prio, delta, on_rq;
+	unsigned long flags;
+	struct rq *rq;
+
+	if (TASK_NICE(p) == nice || nice < -20 || nice > 19)
+		return;
+	/*
+	 * We have to be careful, if called from sys_setpriority(),
+	 * the task might be in the middle of scheduling on another CPU.
+	 */
+	rq = task_rq_lock(p, &flags);
+	/*
+	 * The RT priorities are set via sched_setscheduler(), but we still
+	 * allow the 'normal' nice value to be set - but as expected
+	 * it wont have any effect on scheduling until the task is
+	 * SCHED_FIFO/SCHED_RR:
+	 */
+	if (task_has_rt_policy(p)) {
+		p->static_prio = NICE_TO_PRIO(nice);
+		goto out_unlock;
+	}
+	on_rq = p->on_rq;
+	if (on_rq)
+		dequeue_task(rq, p, 0);
+
+	p->static_prio = NICE_TO_PRIO(nice);
+	set_load_weight(p);
+	old_prio = p->prio;
+	p->prio = effective_prio(p);
+	delta = p->prio - old_prio;
+
+	if (on_rq) {
+		enqueue_task(rq, p, 0);
+		/*
+		 * If the task increased its priority or is running and
+		 * lowered its priority, then reschedule its CPU:
+		 */
+		if (delta < 0 || (delta > 0 && task_running(rq, p)))
+			resched_task(rq->curr);
+	}
+out_unlock:
+	task_rq_unlock(rq, p, &flags);
+}
+EXPORT_SYMBOL(set_user_nice);
+
+/*
+ * can_nice - check if a task can reduce its nice value
+ * @p: task
+ * @nice: nice value
+ */
+int can_nice(const struct task_struct *p, const int nice)
+{
+	/* convert nice value [19,-20] to rlimit style value [1,40] */
+	int nice_rlim = 20 - nice;
+
+	return (nice_rlim <= task_rlimit(p, RLIMIT_NICE) ||
+		capable(CAP_SYS_NICE));
+}
+
+#ifdef __ARCH_WANT_SYS_NICE
+
+/*
+ * sys_nice - change the priority of the current process.
+ * @increment: priority increment
+ *
+ * sys_setpriority is a more generic, but much slower function that
+ * does similar things.
+ */
+SYSCALL_DEFINE1(nice, int, increment)
+{
+	long nice, retval;
+
+	/*
+	 * Setpriority might change our priority at the same moment.
+	 * We don't have to worry. Conceptually one call occurs first
+	 * and we have a single winner.
+	 */
+	if (increment < -40)
+		increment = -40;
+	if (increment > 40)
+		increment = 40;
+
+	nice = TASK_NICE(current) + increment;
+	if (nice < -20)
+		nice = -20;
+	if (nice > 19)
+		nice = 19;
+
+	if (increment < 0 && !can_nice(current, nice))
+		return -EPERM;
+
+	retval = security_task_setnice(current, nice);
+	if (retval)
+		return retval;
+
+	set_user_nice(current, nice);
+	return 0;
+}
+
+#endif
+
+/**
+ * task_prio - return the priority value of a given task.
+ * @p: the task in question.
+ *
+ * This is the priority value as seen by users in /proc.
+ * RT tasks are offset by -200. Normal tasks are centered
+ * around 0, value goes from -16 to +15.
+ */
+int task_prio(const struct task_struct *p)
+{
+	return p->prio - MAX_RT_PRIO;
+}
+
+/**
+ * task_nice - return the nice value of a given task.
+ * @p: the task in question.
+ */
+int task_nice(const struct task_struct *p)
+{
+	return TASK_NICE(p);
+}
+EXPORT_SYMBOL(task_nice);
+
+/**
+ * idle_cpu - is a given cpu idle currently?
+ * @cpu: the processor in question.
+ */
+int idle_cpu(int cpu)
+{
+	struct rq *rq = cpu_rq(cpu);
+
+	if (rq->curr != rq->idle)
+		return 0;
+
+	if (rq->nr_running)
+		return 0;
+
+#ifdef CONFIG_SMP
+	if (!llist_empty(&rq->wake_list))
+		return 0;
+#endif
+
+	return 1;
+}
+
+/**
+ * idle_task - return the idle task for a given cpu.
+ * @cpu: the processor in question.
+ */
+struct task_struct *idle_task(int cpu)
+{
+	return cpu_rq(cpu)->idle;
+}
+
+/**
+ * find_process_by_pid - find a process with a matching PID value.
+ * @pid: the pid in question.
+ */
+static struct task_struct *find_process_by_pid(pid_t pid)
+{
+	return pid ? find_task_by_vpid(pid) : current;
+}
+
+/* Actually do priority change: must hold rq lock. */
+static void
+__setscheduler(struct rq *rq, struct task_struct *p, int policy, int prio)
+{
+	p->policy = policy;
+	p->rt_priority = prio;
+	p->normal_prio = normal_prio(p);
+	/* we are holding p->pi_lock already */
+	p->prio = rt_mutex_getprio(p);
+	if (rt_prio(p->prio))
+		p->sched_class = &rt_sched_class;
+	else
+		p->sched_class = &fair_sched_class;
+	set_load_weight(p);
+}
+
+/*
+ * check the target process has a UID that matches the current process's
+ */
+static bool check_same_owner(struct task_struct *p)
+{
+	const struct cred *cred = current_cred(), *pcred;
+	bool match;
+
+	rcu_read_lock();
+	pcred = __task_cred(p);
+	if (cred->user->user_ns == pcred->user->user_ns)
+		match = (cred->euid == pcred->euid ||
+			 cred->euid == pcred->uid);
+	else
+		match = false;
+	rcu_read_unlock();
+	return match;
+}
+
+static int __sched_setscheduler(struct task_struct *p, int policy,
+				const struct sched_param *param, bool user)
+{
+	int retval, oldprio, oldpolicy = -1, on_rq, running;
+	unsigned long flags;
+	const struct sched_class *prev_class;
+	struct rq *rq;
+	int reset_on_fork;
+
+	/* may grab non-irq protected spin_locks */
+	BUG_ON(in_interrupt());
+recheck:
+	/* double check policy once rq lock held */
+	if (policy < 0) {
+		reset_on_fork = p->sched_reset_on_fork;
+		policy = oldpolicy = p->policy;
+	} else {
+		reset_on_fork = !!(policy & SCHED_RESET_ON_FORK);
+		policy &= ~SCHED_RESET_ON_FORK;
+
+		if (policy != SCHED_FIFO && policy != SCHED_RR &&
+				policy != SCHED_NORMAL && policy != SCHED_BATCH &&
+				policy != SCHED_IDLE)
+			return -EINVAL;
+	}
+
+	/*
+	 * Valid priorities for SCHED_FIFO and SCHED_RR are
+	 * 1..MAX_USER_RT_PRIO-1, valid priority for SCHED_NORMAL,
+	 * SCHED_BATCH and SCHED_IDLE is 0.
+	 */
+	if (param->sched_priority < 0 ||
+	    (p->mm && param->sched_priority > MAX_USER_RT_PRIO-1) ||
+	    (!p->mm && param->sched_priority > MAX_RT_PRIO-1))
+		return -EINVAL;
+	if (rt_policy(policy) != (param->sched_priority != 0))
+		return -EINVAL;
+
+	/*
+	 * Allow unprivileged RT tasks to decrease priority:
+	 */
+	if (user && !capable(CAP_SYS_NICE)) {
+		if (rt_policy(policy)) {
+			unsigned long rlim_rtprio =
+					task_rlimit(p, RLIMIT_RTPRIO);
+
+			/* can't set/change the rt policy */
+			if (policy != p->policy && !rlim_rtprio)
+				return -EPERM;
+
+			/* can't increase priority */
+			if (param->sched_priority > p->rt_priority &&
+			    param->sched_priority > rlim_rtprio)
+				return -EPERM;
+		}
+
+		/*
+		 * Treat SCHED_IDLE as nice 20. Only allow a switch to
+		 * SCHED_NORMAL if the RLIMIT_NICE would normally permit it.
+		 */
+		if (p->policy == SCHED_IDLE && policy != SCHED_IDLE) {
+			if (!can_nice(p, TASK_NICE(p)))
+				return -EPERM;
+		}
+
+		/* can't change other user's priorities */
+		if (!check_same_owner(p))
+			return -EPERM;
+
+		/* Normal users shall not reset the sched_reset_on_fork flag */
+		if (p->sched_reset_on_fork && !reset_on_fork)
+			return -EPERM;
+	}
+
+	if (user) {
+		retval = security_task_setscheduler(p);
+		if (retval)
+			return retval;
+	}
+
+	/*
+	 * make sure no PI-waiters arrive (or leave) while we are
+	 * changing the priority of the task:
+	 *
+	 * To be able to change p->policy safely, the appropriate
+	 * runqueue lock must be held.
+	 */
+	rq = task_rq_lock(p, &flags);
+
+	/*
+	 * Changing the policy of the stop threads its a very bad idea
+	 */
+	if (p == rq->stop) {
+		task_rq_unlock(rq, p, &flags);
+		return -EINVAL;
+	}
+
+	/*
+	 * If not changing anything there's no need to proceed further:
+	 */
+	if (unlikely(policy == p->policy && (!rt_policy(policy) ||
+			param->sched_priority == p->rt_priority))) {
+
+		__task_rq_unlock(rq);
+		raw_spin_unlock_irqrestore(&p->pi_lock, flags);
+		return 0;
+	}
+
+#ifdef CONFIG_RT_GROUP_SCHED
+	if (user) {
+		/*
+		 * Do not allow realtime tasks into groups that have no runtime
+		 * assigned.
+		 */
+		if (rt_bandwidth_enabled() && rt_policy(policy) &&
+				task_group(p)->rt_bandwidth.rt_runtime == 0 &&
+				!task_group_is_autogroup(task_group(p))) {
+			task_rq_unlock(rq, p, &flags);
+			return -EPERM;
+		}
+	}
+#endif
+
+	/* recheck policy now with rq lock held */
+	if (unlikely(oldpolicy != -1 && oldpolicy != p->policy)) {
+		policy = oldpolicy = -1;
+		task_rq_unlock(rq, p, &flags);
+		goto recheck;
+	}
+	on_rq = p->on_rq;
+	running = task_current(rq, p);
+	if (on_rq)
+		deactivate_task(rq, p, 0);
+	if (running)
+		p->sched_class->put_prev_task(rq, p);
+
+	p->sched_reset_on_fork = reset_on_fork;
+
+	oldprio = p->prio;
+	prev_class = p->sched_class;
+	__setscheduler(rq, p, policy, param->sched_priority);
+
+	if (running)
+		p->sched_class->set_curr_task(rq);
+	if (on_rq)
+		activate_task(rq, p, 0);
+
+	check_class_changed(rq, p, prev_class, oldprio);
+	task_rq_unlock(rq, p, &flags);
+
+	rt_mutex_adjust_pi(p);
+
+	return 0;
+}
+
+/**
+ * sched_setscheduler - change the scheduling policy and/or RT priority of a thread.
+ * @p: the task in question.
+ * @policy: new policy.
+ * @param: structure containing the new RT priority.
+ *
+ * NOTE that the task may be already dead.
+ */
+int sched_setscheduler(struct task_struct *p, int policy,
+		       const struct sched_param *param)
+{
+	return __sched_setscheduler(p, policy, param, true);
+}
+EXPORT_SYMBOL_GPL(sched_setscheduler);
+
+/**
+ * sched_setscheduler_nocheck - change the scheduling policy and/or RT priority of a thread from kernelspace.
+ * @p: the task in question.
+ * @policy: new policy.
+ * @param: structure containing the new RT priority.
+ *
+ * Just like sched_setscheduler, only don't bother checking if the
+ * current context has permission.  For example, this is needed in
+ * stop_machine(): we create temporary high priority worker threads,
+ * but our caller might not have that capability.
+ */
+int sched_setscheduler_nocheck(struct task_struct *p, int policy,
+			       const struct sched_param *param)
+{
+	return __sched_setscheduler(p, policy, param, false);
+}
+
+static int
+do_sched_setscheduler(pid_t pid, int policy, struct sched_param __user *param)
+{
+	struct sched_param lparam;
+	struct task_struct *p;
+	int retval;
+
+	if (!param || pid < 0)
+		return -EINVAL;
+	if (copy_from_user(&lparam, param, sizeof(struct sched_param)))
+		return -EFAULT;
+
+	rcu_read_lock();
+	retval = -ESRCH;
+	p = find_process_by_pid(pid);
+	if (p != NULL)
+		retval = sched_setscheduler(p, policy, &lparam);
+	rcu_read_unlock();
+
+	return retval;
+}
+
+/**
+ * sys_sched_setscheduler - set/change the scheduler policy and RT priority
+ * @pid: the pid in question.
+ * @policy: new policy.
+ * @param: structure containing the new RT priority.
+ */
+SYSCALL_DEFINE3(sched_setscheduler, pid_t, pid, int, policy,
+		struct sched_param __user *, param)
+{
+	/* negative values for policy are not valid */
+	if (policy < 0)
+		return -EINVAL;
+
+	return do_sched_setscheduler(pid, policy, param);
+}
+
+/**
+ * sys_sched_setparam - set/change the RT priority of a thread
+ * @pid: the pid in question.
+ * @param: structure containing the new RT priority.
+ */
+SYSCALL_DEFINE2(sched_setparam, pid_t, pid, struct sched_param __user *, param)
+{
+	return do_sched_setscheduler(pid, -1, param);
+}
+
+/**
+ * sys_sched_getscheduler - get the policy (scheduling class) of a thread
+ * @pid: the pid in question.
+ */
+SYSCALL_DEFINE1(sched_getscheduler, pid_t, pid)
+{
+	struct task_struct *p;
+	int retval;
+
+	if (pid < 0)
+		return -EINVAL;
+
+	retval = -ESRCH;
+	rcu_read_lock();
+	p = find_process_by_pid(pid);
+	if (p) {
+		retval = security_task_getscheduler(p);
+		if (!retval)
+			retval = p->policy
+				| (p->sched_reset_on_fork ? SCHED_RESET_ON_FORK : 0);
+	}
+	rcu_read_unlock();
+	return retval;
+}
+
+/**
+ * sys_sched_getparam - get the RT priority of a thread
+ * @pid: the pid in question.
+ * @param: structure containing the RT priority.
+ */
+SYSCALL_DEFINE2(sched_getparam, pid_t, pid, struct sched_param __user *, param)
+{
+	struct sched_param lp;
+	struct task_struct *p;
+	int retval;
+
+	if (!param || pid < 0)
+		return -EINVAL;
+
+	rcu_read_lock();
+	p = find_process_by_pid(pid);
+	retval = -ESRCH;
+	if (!p)
+		goto out_unlock;
+
+	retval = security_task_getscheduler(p);
+	if (retval)
+		goto out_unlock;
+
+	lp.sched_priority = p->rt_priority;
+	rcu_read_unlock();
+
+	/*
+	 * This one might sleep, we cannot do it with a spinlock held ...
+	 */
+	retval = copy_to_user(param, &lp, sizeof(*param)) ? -EFAULT : 0;
+
+	return retval;
+
+out_unlock:
+	rcu_read_unlock();
+	return retval;
+}
+
+long sched_setaffinity(pid_t pid, const struct cpumask *in_mask)
+{
+	cpumask_var_t cpus_allowed, new_mask;
+	struct task_struct *p;
+	int retval;
+
+	get_online_cpus();
+	rcu_read_lock();
+
+	p = find_process_by_pid(pid);
+	if (!p) {
+		rcu_read_unlock();
+		put_online_cpus();
+		return -ESRCH;
+	}
+
+	/* Prevent p going away */
+	get_task_struct(p);
+	rcu_read_unlock();
+
+	if (!alloc_cpumask_var(&cpus_allowed, GFP_KERNEL)) {
+		retval = -ENOMEM;
+		goto out_put_task;
+	}
+	if (!alloc_cpumask_var(&new_mask, GFP_KERNEL)) {
+		retval = -ENOMEM;
+		goto out_free_cpus_allowed;
+	}
+	retval = -EPERM;
+	if (!check_same_owner(p) && !ns_capable(task_user_ns(p), CAP_SYS_NICE))
+		goto out_unlock;
+
+	retval = security_task_setscheduler(p);
+	if (retval)
+		goto out_unlock;
+
+	cpuset_cpus_allowed(p, cpus_allowed);
+	cpumask_and(new_mask, in_mask, cpus_allowed);
+again:
+	retval = set_cpus_allowed_ptr(p, new_mask);
+
+	if (!retval) {
+		cpuset_cpus_allowed(p, cpus_allowed);
+		if (!cpumask_subset(new_mask, cpus_allowed)) {
+			/*
+			 * We must have raced with a concurrent cpuset
+			 * update. Just reset the cpus_allowed to the
+			 * cpuset's cpus_allowed
+			 */
+			cpumask_copy(new_mask, cpus_allowed);
+			goto again;
+		}
+	}
+out_unlock:
+	free_cpumask_var(new_mask);
+out_free_cpus_allowed:
+	free_cpumask_var(cpus_allowed);
+out_put_task:
+	put_task_struct(p);
+	put_online_cpus();
+	return retval;
+}
+
+static int get_user_cpu_mask(unsigned long __user *user_mask_ptr, unsigned len,
+			     struct cpumask *new_mask)
+{
+	if (len < cpumask_size())
+		cpumask_clear(new_mask);
+	else if (len > cpumask_size())
+		len = cpumask_size();
+
+	return copy_from_user(new_mask, user_mask_ptr, len) ? -EFAULT : 0;
+}
+
+/**
+ * sys_sched_setaffinity - set the cpu affinity of a process
+ * @pid: pid of the process
+ * @len: length in bytes of the bitmask pointed to by user_mask_ptr
+ * @user_mask_ptr: user-space pointer to the new cpu mask
+ */
+SYSCALL_DEFINE3(sched_setaffinity, pid_t, pid, unsigned int, len,
+		unsigned long __user *, user_mask_ptr)
+{
+	cpumask_var_t new_mask;
+	int retval;
+
+	if (!alloc_cpumask_var(&new_mask, GFP_KERNEL))
+		return -ENOMEM;
+
+	retval = get_user_cpu_mask(user_mask_ptr, len, new_mask);
+	if (retval == 0)
+		retval = sched_setaffinity(pid, new_mask);
+	free_cpumask_var(new_mask);
+	return retval;
+}
+
+long sched_getaffinity(pid_t pid, struct cpumask *mask)
+{
+	struct task_struct *p;
+	unsigned long flags;
+	int retval;
+
+	get_online_cpus();
+	rcu_read_lock();
+
+	retval = -ESRCH;
+	p = find_process_by_pid(pid);
+	if (!p)
+		goto out_unlock;
+
+	retval = security_task_getscheduler(p);
+	if (retval)
+		goto out_unlock;
+
+	raw_spin_lock_irqsave(&p->pi_lock, flags);
+	cpumask_and(mask, &p->cpus_allowed, cpu_online_mask);
+	raw_spin_unlock_irqrestore(&p->pi_lock, flags);
+
+out_unlock:
+	rcu_read_unlock();
+	put_online_cpus();
+
+	return retval;
+}
+
+/**
+ * sys_sched_getaffinity - get the cpu affinity of a process
+ * @pid: pid of the process
+ * @len: length in bytes of the bitmask pointed to by user_mask_ptr
+ * @user_mask_ptr: user-space pointer to hold the current cpu mask
+ */
+SYSCALL_DEFINE3(sched_getaffinity, pid_t, pid, unsigned int, len,
+		unsigned long __user *, user_mask_ptr)
+{
+	int ret;
+	cpumask_var_t mask;
+
+	if ((len * BITS_PER_BYTE) < nr_cpu_ids)
+		return -EINVAL;
+	if (len & (sizeof(unsigned long)-1))
+		return -EINVAL;
+
+	if (!alloc_cpumask_var(&mask, GFP_KERNEL))
+		return -ENOMEM;
+
+	ret = sched_getaffinity(pid, mask);
+	if (ret == 0) {
+		size_t retlen = min_t(size_t, len, cpumask_size());
+
+		if (copy_to_user(user_mask_ptr, mask, retlen))
+			ret = -EFAULT;
+		else
+			ret = retlen;
+	}
+	free_cpumask_var(mask);
+
+	return ret;
+}
+
+/**
+ * sys_sched_yield - yield the current processor to other threads.
+ *
+ * This function yields the current CPU to other tasks. If there are no
+ * other threads running on this CPU then this function will return.
+ */
+SYSCALL_DEFINE0(sched_yield)
+{
+	struct rq *rq = this_rq_lock();
+
+	schedstat_inc(rq, yld_count);
+	current->sched_class->yield_task(rq);
+
+	/*
+	 * Since we are going to call schedule() anyway, there's
+	 * no need to preempt or enable interrupts:
+	 */
+	__release(rq->lock);
+	spin_release(&rq->lock.dep_map, 1, _THIS_IP_);
+	do_raw_spin_unlock(&rq->lock);
+	preempt_enable_no_resched();
+
+	schedule();
+
+	return 0;
+}
+
+static inline int should_resched(void)
+{
+	return need_resched() && !(preempt_count() & PREEMPT_ACTIVE);
+}
+
+static void __cond_resched(void)
+{
+	add_preempt_count(PREEMPT_ACTIVE);
+	__schedule();
+	sub_preempt_count(PREEMPT_ACTIVE);
+}
+
+int __sched _cond_resched(void)
+{
+	if (should_resched()) {
+		__cond_resched();
+		return 1;
+	}
+	return 0;
+}
+EXPORT_SYMBOL(_cond_resched);
+
+/*
+ * __cond_resched_lock() - if a reschedule is pending, drop the given lock,
+ * call schedule, and on return reacquire the lock.
+ *
+ * This works OK both with and without CONFIG_PREEMPT. We do strange low-level
+ * operations here to prevent schedule() from being called twice (once via
+ * spin_unlock(), once by hand).
+ */
+int __cond_resched_lock(spinlock_t *lock)
+{
+	int resched = should_resched();
+	int ret = 0;
+
+	lockdep_assert_held(lock);
+
+	if (spin_needbreak(lock) || resched) {
+		spin_unlock(lock);
+		if (resched)
+			__cond_resched();
+		else
+			cpu_relax();
+		ret = 1;
+		spin_lock(lock);
+	}
+	return ret;
+}
+EXPORT_SYMBOL(__cond_resched_lock);
+
+int __sched __cond_resched_softirq(void)
+{
+	BUG_ON(!in_softirq());
+
+	if (should_resched()) {
+		local_bh_enable();
+		__cond_resched();
+		local_bh_disable();
+		return 1;
+	}
+	return 0;
+}
+EXPORT_SYMBOL(__cond_resched_softirq);
+
+/**
+ * yield - yield the current processor to other threads.
+ *
+ * This is a shortcut for kernel-space yielding - it marks the
+ * thread runnable and calls sys_sched_yield().
+ */
+void __sched yield(void)
+{
+	set_current_state(TASK_RUNNING);
+	sys_sched_yield();
+}
+EXPORT_SYMBOL(yield);
+
+/**
+ * yield_to - yield the current processor to another thread in
+ * your thread group, or accelerate that thread toward the
+ * processor it's on.
+ * @p: target task
+ * @preempt: whether task preemption is allowed or not
+ *
+ * It's the caller's job to ensure that the target task struct
+ * can't go away on us before we can do any checks.
+ *
+ * Returns true if we indeed boosted the target task.
+ */
+bool __sched yield_to(struct task_struct *p, bool preempt)
+{
+	struct task_struct *curr = current;
+	struct rq *rq, *p_rq;
+	unsigned long flags;
+	bool yielded = 0;
+
+	local_irq_save(flags);
+	rq = this_rq();
+
+again:
+	p_rq = task_rq(p);
+	double_rq_lock(rq, p_rq);
+	while (task_rq(p) != p_rq) {
+		double_rq_unlock(rq, p_rq);
+		goto again;
+	}
+
+	if (!curr->sched_class->yield_to_task)
+		goto out;
+
+	if (curr->sched_class != p->sched_class)
+		goto out;
+
+	if (task_running(p_rq, p) || p->state)
+		goto out;
+
+	yielded = curr->sched_class->yield_to_task(rq, p, preempt);
+	if (yielded) {
+		schedstat_inc(rq, yld_count);
+		/*
+		 * Make p's CPU reschedule; pick_next_entity takes care of
+		 * fairness.
+		 */
+		if (preempt && rq != p_rq)
+			resched_task(p_rq->curr);
+	} else {
+		/*
+		 * We might have set it in task_yield_fair(), but are
+		 * not going to schedule(), so don't want to skip
+		 * the next update.
+		 */
+		rq->skip_clock_update = 0;
+	}
+
+out:
+	double_rq_unlock(rq, p_rq);
+	local_irq_restore(flags);
+
+	if (yielded)
+		schedule();
+
+	return yielded;
+}
+EXPORT_SYMBOL_GPL(yield_to);
+
+/*
+ * This task is about to go to sleep on IO. Increment rq->nr_iowait so
+ * that process accounting knows that this is a task in IO wait state.
+ */
+void __sched io_schedule(void)
+{
+	struct rq *rq = raw_rq();
+
+	delayacct_blkio_start();
+	atomic_inc(&rq->nr_iowait);
+	blk_flush_plug(current);
+	current->in_iowait = 1;
+	schedule();
+	current->in_iowait = 0;
+	atomic_dec(&rq->nr_iowait);
+	delayacct_blkio_end();
+}
+EXPORT_SYMBOL(io_schedule);
+
+long __sched io_schedule_timeout(long timeout)
+{
+	struct rq *rq = raw_rq();
+	long ret;
+
+	delayacct_blkio_start();
+	atomic_inc(&rq->nr_iowait);
+	blk_flush_plug(current);
+	current->in_iowait = 1;
+	ret = schedule_timeout(timeout);
+	current->in_iowait = 0;
+	atomic_dec(&rq->nr_iowait);
+	delayacct_blkio_end();
+	return ret;
+}
+
+/**
+ * sys_sched_get_priority_max - return maximum RT priority.
+ * @policy: scheduling class.
+ *
+ * this syscall returns the maximum rt_priority that can be used
+ * by a given scheduling class.
+ */
+SYSCALL_DEFINE1(sched_get_priority_max, int, policy)
+{
+	int ret = -EINVAL;
+
+	switch (policy) {
+	case SCHED_FIFO:
+	case SCHED_RR:
+		ret = MAX_USER_RT_PRIO-1;
+		break;
+	case SCHED_NORMAL:
+	case SCHED_BATCH:
+	case SCHED_IDLE:
+		ret = 0;
+		break;
+	}
+	return ret;
+}
+
+/**
+ * sys_sched_get_priority_min - return minimum RT priority.
+ * @policy: scheduling class.
+ *
+ * this syscall returns the minimum rt_priority that can be used
+ * by a given scheduling class.
+ */
+SYSCALL_DEFINE1(sched_get_priority_min, int, policy)
+{
+	int ret = -EINVAL;
+
+	switch (policy) {
+	case SCHED_FIFO:
+	case SCHED_RR:
+		ret = 1;
+		break;
+	case SCHED_NORMAL:
+	case SCHED_BATCH:
+	case SCHED_IDLE:
+		ret = 0;
+	}
+	return ret;
+}
+
+/**
+ * sys_sched_rr_get_interval - return the default timeslice of a process.
+ * @pid: pid of the process.
+ * @interval: userspace pointer to the timeslice value.
+ *
+ * this syscall writes the default timeslice value of a given process
+ * into the user-space timespec buffer. A value of '0' means infinity.
+ */
+SYSCALL_DEFINE2(sched_rr_get_interval, pid_t, pid,
+		struct timespec __user *, interval)
+{
+	struct task_struct *p;
+	unsigned int time_slice;
+	unsigned long flags;
+	struct rq *rq;
+	int retval;
+	struct timespec t;
+
+	if (pid < 0)
+		return -EINVAL;
+
+	retval = -ESRCH;
+	rcu_read_lock();
+	p = find_process_by_pid(pid);
+	if (!p)
+		goto out_unlock;
+
+	retval = security_task_getscheduler(p);
+	if (retval)
+		goto out_unlock;
+
+	rq = task_rq_lock(p, &flags);
+	time_slice = p->sched_class->get_rr_interval(rq, p);
+	task_rq_unlock(rq, p, &flags);
+
+	rcu_read_unlock();
+	jiffies_to_timespec(time_slice, &t);
+	retval = copy_to_user(interval, &t, sizeof(t)) ? -EFAULT : 0;
+	return retval;
+
+out_unlock:
+	rcu_read_unlock();
+	return retval;
+}
+
+static const char stat_nam[] = TASK_STATE_TO_CHAR_STR;
+
+void sched_show_task(struct task_struct *p)
+{
+	unsigned long free = 0;
+	unsigned state;
+
+	state = p->state ? __ffs(p->state) + 1 : 0;
+	printk(KERN_INFO "%-15.15s %c", p->comm,
+		state < sizeof(stat_nam) - 1 ? stat_nam[state] : '?');
+#if BITS_PER_LONG == 32
+	if (state == TASK_RUNNING)
+		printk(KERN_CONT " running  ");
+	else
+		printk(KERN_CONT " %08lx ", thread_saved_pc(p));
+#else
+	if (state == TASK_RUNNING)
+		printk(KERN_CONT "  running task    ");
+	else
+		printk(KERN_CONT " %016lx ", thread_saved_pc(p));
+#endif
+#ifdef CONFIG_DEBUG_STACK_USAGE
+	free = stack_not_used(p);
+#endif
+	printk(KERN_CONT "%5lu %5d %6d 0x%08lx\n", free,
+		task_pid_nr(p), task_pid_nr(rcu_dereference(p->real_parent)),
+		(unsigned long)task_thread_info(p)->flags);
+
+	show_stack(p, NULL);
+}
+
+void show_state_filter(unsigned long state_filter)
+{
+	struct task_struct *g, *p;
+
+#if BITS_PER_LONG == 32
+	printk(KERN_INFO
+		"  task                PC stack   pid father\n");
+#else
+	printk(KERN_INFO
+		"  task                        PC stack   pid father\n");
+#endif
+	rcu_read_lock();
+	do_each_thread(g, p) {
+		/*
+		 * reset the NMI-timeout, listing all files on a slow
+		 * console might take a lot of time:
+		 */
+		touch_nmi_watchdog();
+		if (!state_filter || (p->state & state_filter))
+			sched_show_task(p);
+	} while_each_thread(g, p);
+
+	touch_all_softlockup_watchdogs();
+
+#ifdef CONFIG_SCHED_DEBUG
+	sysrq_sched_debug_show();
+#endif
+	rcu_read_unlock();
+	/*
+	 * Only show locks if all tasks are dumped:
+	 */
+	if (!state_filter)
+		debug_show_all_locks();
+}
+
+void __cpuinit init_idle_bootup_task(struct task_struct *idle)
+{
+	idle->sched_class = &idle_sched_class;
+}
+
+/**
+ * init_idle - set up an idle thread for a given CPU
+ * @idle: task in question
+ * @cpu: cpu the idle task belongs to
+ *
+ * NOTE: this function does not set the idle thread's NEED_RESCHED
+ * flag, to make booting more robust.
+ */
+void __cpuinit init_idle(struct task_struct *idle, int cpu)
+{
+	struct rq *rq = cpu_rq(cpu);
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&rq->lock, flags);
+
+	__sched_fork(idle);
+	idle->state = TASK_RUNNING;
+	idle->se.exec_start = sched_clock();
+
+	do_set_cpus_allowed(idle, cpumask_of(cpu));
+	/*
+	 * We're having a chicken and egg problem, even though we are
+	 * holding rq->lock, the cpu isn't yet set to this cpu so the
+	 * lockdep check in task_group() will fail.
+	 *
+	 * Similar case to sched_fork(). / Alternatively we could
+	 * use task_rq_lock() here and obtain the other rq->lock.
+	 *
+	 * Silence PROVE_RCU
+	 */
+	rcu_read_lock();
+	__set_task_cpu(idle, cpu);
+	rcu_read_unlock();
+
+	rq->curr = rq->idle = idle;
+#if defined(CONFIG_SMP)
+	idle->on_cpu = 1;
+#endif
+	raw_spin_unlock_irqrestore(&rq->lock, flags);
+
+	/* Set the preempt count _outside_ the spinlocks! */
+	task_thread_info(idle)->preempt_count = 0;
+
+	/*
+	 * The idle tasks have their own, simple scheduling class:
+	 */
+	idle->sched_class = &idle_sched_class;
+	ftrace_graph_init_idle_task(idle, cpu);
+#if defined(CONFIG_SMP)
+	sprintf(idle->comm, "%s/%d", INIT_TASK_COMM, cpu);
+#endif
+}
+
+#ifdef CONFIG_SMP
+void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask)
+{
+	if (p->sched_class && p->sched_class->set_cpus_allowed)
+		p->sched_class->set_cpus_allowed(p, new_mask);
+
+	cpumask_copy(&p->cpus_allowed, new_mask);
+	p->rt.nr_cpus_allowed = cpumask_weight(new_mask);
+}
+
+/*
+ * This is how migration works:
+ *
+ * 1) we invoke migration_cpu_stop() on the target CPU using
+ *    stop_one_cpu().
+ * 2) stopper starts to run (implicitly forcing the migrated thread
+ *    off the CPU)
+ * 3) it checks whether the migrated task is still in the wrong runqueue.
+ * 4) if it's in the wrong runqueue then the migration thread removes
+ *    it and puts it into the right queue.
+ * 5) stopper completes and stop_one_cpu() returns and the migration
+ *    is done.
+ */
+
+/*
+ * Change a given task's CPU affinity. Migrate the thread to a
+ * proper CPU and schedule it away if the CPU it's executing on
+ * is removed from the allowed bitmask.
+ *
+ * NOTE: the caller must have a valid reference to the task, the
+ * task must not exit() & deallocate itself prematurely. The
+ * call is not atomic; no spinlocks may be held.
+ */
+int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
+{
+	unsigned long flags;
+	struct rq *rq;
+	unsigned int dest_cpu;
+	int ret = 0;
+
+	rq = task_rq_lock(p, &flags);
+
+	if (cpumask_equal(&p->cpus_allowed, new_mask))
+		goto out;
+
+	if (!cpumask_intersects(new_mask, cpu_active_mask)) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	if (unlikely((p->flags & PF_THREAD_BOUND) && p != current)) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	do_set_cpus_allowed(p, new_mask);
+
+	/* Can the task run on the task's current CPU? If so, we're done */
+	if (cpumask_test_cpu(task_cpu(p), new_mask))
+		goto out;
+
+	dest_cpu = cpumask_any_and(cpu_active_mask, new_mask);
+	if (p->on_rq) {
+		struct migration_arg arg = { p, dest_cpu };
+		/* Need help from migration thread: drop lock and wait. */
+		task_rq_unlock(rq, p, &flags);
+		stop_one_cpu(cpu_of(rq), migration_cpu_stop, &arg);
+		tlb_migrate_finish(p->mm);
+		return 0;
+	}
+out:
+	task_rq_unlock(rq, p, &flags);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(set_cpus_allowed_ptr);
+
+/*
+ * Move (not current) task off this cpu, onto dest cpu. We're doing
+ * this because either it can't run here any more (set_cpus_allowed()
+ * away from this CPU, or CPU going down), or because we're
+ * attempting to rebalance this task on exec (sched_exec).
+ *
+ * So we race with normal scheduler movements, but that's OK, as long
+ * as the task is no longer on this CPU.
+ *
+ * Returns non-zero if task was successfully migrated.
+ */
+static int __migrate_task(struct task_struct *p, int src_cpu, int dest_cpu)
+{
+	struct rq *rq_dest, *rq_src;
+	int ret = 0;
+
+	if (unlikely(!cpu_active(dest_cpu)))
+		return ret;
+
+	rq_src = cpu_rq(src_cpu);
+	rq_dest = cpu_rq(dest_cpu);
+
+	raw_spin_lock(&p->pi_lock);
+	double_rq_lock(rq_src, rq_dest);
+	/* Already moved. */
+	if (task_cpu(p) != src_cpu)
+		goto done;
+	/* Affinity changed (again). */
+	if (!cpumask_test_cpu(dest_cpu, tsk_cpus_allowed(p)))
+		goto fail;
+
+	/*
+	 * If we're not on a rq, the next wake-up will ensure we're
+	 * placed properly.
+	 */
+	if (p->on_rq) {
+		deactivate_task(rq_src, p, 0);
+		set_task_cpu(p, dest_cpu);
+		activate_task(rq_dest, p, 0);
+		check_preempt_curr(rq_dest, p, 0);
+	}
+done:
+	ret = 1;
+fail:
+	double_rq_unlock(rq_src, rq_dest);
+	raw_spin_unlock(&p->pi_lock);
+	return ret;
+}
+
+/*
+ * migration_cpu_stop - this will be executed by a highprio stopper thread
+ * and performs thread migration by bumping thread off CPU then
+ * 'pushing' onto another runqueue.
+ */
+static int migration_cpu_stop(void *data)
+{
+	struct migration_arg *arg = data;
+
+	/*
+	 * The original target cpu might have gone down and we might
+	 * be on another cpu but it doesn't matter.
+	 */
+	local_irq_disable();
+	__migrate_task(arg->task, raw_smp_processor_id(), arg->dest_cpu);
+	local_irq_enable();
+	return 0;
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+
+/*
+ * Ensures that the idle task is using init_mm right before its cpu goes
+ * offline.
+ */
+void idle_task_exit(void)
+{
+	struct mm_struct *mm = current->active_mm;
+
+	BUG_ON(cpu_online(smp_processor_id()));
+
+	if (mm != &init_mm)
+		switch_mm(mm, &init_mm, current);
+	mmdrop(mm);
+}
+
+/*
+ * While a dead CPU has no uninterruptible tasks queued at this point,
+ * it might still have a nonzero ->nr_uninterruptible counter, because
+ * for performance reasons the counter is not stricly tracking tasks to
+ * their home CPUs. So we just add the counter to another CPU's counter,
+ * to keep the global sum constant after CPU-down:
+ */
+static void migrate_nr_uninterruptible(struct rq *rq_src)
+{
+	struct rq *rq_dest = cpu_rq(cpumask_any(cpu_active_mask));
+
+	rq_dest->nr_uninterruptible += rq_src->nr_uninterruptible;
+	rq_src->nr_uninterruptible = 0;
+}
+
+/*
+ * remove the tasks which were accounted by rq from calc_load_tasks.
+ */
+static void calc_global_load_remove(struct rq *rq)
+{
+	atomic_long_sub(rq->calc_load_active, &calc_load_tasks);
+	rq->calc_load_active = 0;
+}
+
+/*
+ * Migrate all tasks from the rq, sleeping tasks will be migrated by
+ * try_to_wake_up()->select_task_rq().
+ *
+ * Called with rq->lock held even though we'er in stop_machine() and
+ * there's no concurrency possible, we hold the required locks anyway
+ * because of lock validation efforts.
+ */
+static void migrate_tasks(unsigned int dead_cpu)
+{
+	struct rq *rq = cpu_rq(dead_cpu);
+	struct task_struct *next, *stop = rq->stop;
+	int dest_cpu;
+
+	/*
+	 * Fudge the rq selection such that the below task selection loop
+	 * doesn't get stuck on the currently eligible stop task.
+	 *
+	 * We're currently inside stop_machine() and the rq is either stuck
+	 * in the stop_machine_cpu_stop() loop, or we're executing this code,
+	 * either way we should never end up calling schedule() until we're
+	 * done here.
+	 */
+	rq->stop = NULL;
+
+	/* Ensure any throttled groups are reachable by pick_next_task */
+	unthrottle_offline_cfs_rqs(rq);
+
+	for ( ; ; ) {
+		/*
+		 * There's this thread running, bail when that's the only
+		 * remaining thread.
+		 */
+		if (rq->nr_running == 1)
+			break;
+
+		next = pick_next_task(rq);
+		BUG_ON(!next);
+		next->sched_class->put_prev_task(rq, next);
+
+		/* Find suitable destination for @next, with force if needed. */
+		dest_cpu = select_fallback_rq(dead_cpu, next);
+		raw_spin_unlock(&rq->lock);
+
+		__migrate_task(next, dead_cpu, dest_cpu);
+
+		raw_spin_lock(&rq->lock);
+	}
+
+	rq->stop = stop;
+}
+
+#endif /* CONFIG_HOTPLUG_CPU */
+
+#if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SYSCTL)
+
+static struct ctl_table sd_ctl_dir[] = {
+	{
+		.procname	= "sched_domain",
+		.mode		= 0555,
+	},
+	{}
+};
+
+static struct ctl_table sd_ctl_root[] = {
+	{
+		.procname	= "kernel",
+		.mode		= 0555,
+		.child		= sd_ctl_dir,
+	},
+	{}
+};
+
+static struct ctl_table *sd_alloc_ctl_entry(int n)
+{
+	struct ctl_table *entry =
+		kcalloc(n, sizeof(struct ctl_table), GFP_KERNEL);
+
+	return entry;
+}
+
+static void sd_free_ctl_entry(struct ctl_table **tablep)
+{
+	struct ctl_table *entry;
+
+	/*
+	 * In the intermediate directories, both the child directory and
+	 * procname are dynamically allocated and could fail but the mode
+	 * will always be set. In the lowest directory the names are
+	 * static strings and all have proc handlers.
+	 */
+	for (entry = *tablep; entry->mode; entry++) {
+		if (entry->child)
+			sd_free_ctl_entry(&entry->child);
+		if (entry->proc_handler == NULL)
+			kfree(entry->procname);
+	}
+
+	kfree(*tablep);
+	*tablep = NULL;
+}
+
+static void
+set_table_entry(struct ctl_table *entry,
+		const char *procname, void *data, int maxlen,
+		umode_t mode, proc_handler *proc_handler)
+{
+	entry->procname = procname;
+	entry->data = data;
+	entry->maxlen = maxlen;
+	entry->mode = mode;
+	entry->proc_handler = proc_handler;
+}
+
+static struct ctl_table *
+sd_alloc_ctl_domain_table(struct sched_domain *sd)
+{
+	struct ctl_table *table = sd_alloc_ctl_entry(13);
+
+	if (table == NULL)
+		return NULL;
+
+	set_table_entry(&table[0], "min_interval", &sd->min_interval,
+		sizeof(long), 0644, proc_doulongvec_minmax);
+	set_table_entry(&table[1], "max_interval", &sd->max_interval,
+		sizeof(long), 0644, proc_doulongvec_minmax);
+	set_table_entry(&table[2], "busy_idx", &sd->busy_idx,
+		sizeof(int), 0644, proc_dointvec_minmax);
+	set_table_entry(&table[3], "idle_idx", &sd->idle_idx,
+		sizeof(int), 0644, proc_dointvec_minmax);
+	set_table_entry(&table[4], "newidle_idx", &sd->newidle_idx,
+		sizeof(int), 0644, proc_dointvec_minmax);
+	set_table_entry(&table[5], "wake_idx", &sd->wake_idx,
+		sizeof(int), 0644, proc_dointvec_minmax);
+	set_table_entry(&table[6], "forkexec_idx", &sd->forkexec_idx,
+		sizeof(int), 0644, proc_dointvec_minmax);
+	set_table_entry(&table[7], "busy_factor", &sd->busy_factor,
+		sizeof(int), 0644, proc_dointvec_minmax);
+	set_table_entry(&table[8], "imbalance_pct", &sd->imbalance_pct,
+		sizeof(int), 0644, proc_dointvec_minmax);
+	set_table_entry(&table[9], "cache_nice_tries",
+		&sd->cache_nice_tries,
+		sizeof(int), 0644, proc_dointvec_minmax);
+	set_table_entry(&table[10], "flags", &sd->flags,
+		sizeof(int), 0644, proc_dointvec_minmax);
+	set_table_entry(&table[11], "name", sd->name,
+		CORENAME_MAX_SIZE, 0444, proc_dostring);
+	/* &table[12] is terminator */
+
+	return table;
+}
+
+static ctl_table *sd_alloc_ctl_cpu_table(int cpu)
+{
+	struct ctl_table *entry, *table;
+	struct sched_domain *sd;
+	int domain_num = 0, i;
+	char buf[32];
+
+	for_each_domain(cpu, sd)
+		domain_num++;
+	entry = table = sd_alloc_ctl_entry(domain_num + 1);
+	if (table == NULL)
+		return NULL;
+
+	i = 0;
+	for_each_domain(cpu, sd) {
+		snprintf(buf, 32, "domain%d", i);
+		entry->procname = kstrdup(buf, GFP_KERNEL);
+		entry->mode = 0555;
+		entry->child = sd_alloc_ctl_domain_table(sd);
+		entry++;
+		i++;
+	}
+	return table;
+}
+
+static struct ctl_table_header *sd_sysctl_header;
+static void register_sched_domain_sysctl(void)
+{
+	int i, cpu_num = num_possible_cpus();
+	struct ctl_table *entry = sd_alloc_ctl_entry(cpu_num + 1);
+	char buf[32];
+
+	WARN_ON(sd_ctl_dir[0].child);
+	sd_ctl_dir[0].child = entry;
+
+	if (entry == NULL)
+		return;
+
+	for_each_possible_cpu(i) {
+		snprintf(buf, 32, "cpu%d", i);
+		entry->procname = kstrdup(buf, GFP_KERNEL);
+		entry->mode = 0555;
+		entry->child = sd_alloc_ctl_cpu_table(i);
+		entry++;
+	}
+
+	WARN_ON(sd_sysctl_header);
+	sd_sysctl_header = register_sysctl_table(sd_ctl_root);
+}
+
+/* may be called multiple times per register */
+static void unregister_sched_domain_sysctl(void)
+{
+	if (sd_sysctl_header)
+		unregister_sysctl_table(sd_sysctl_header);
+	sd_sysctl_header = NULL;
+	if (sd_ctl_dir[0].child)
+		sd_free_ctl_entry(&sd_ctl_dir[0].child);
+}
+#else
+static void register_sched_domain_sysctl(void)
+{
+}
+static void unregister_sched_domain_sysctl(void)
+{
+}
+#endif
+
+static void set_rq_online(struct rq *rq)
+{
+	if (!rq->online) {
+		const struct sched_class *class;
+
+		cpumask_set_cpu(rq->cpu, rq->rd->online);
+		rq->online = 1;
+
+		for_each_class(class) {
+			if (class->rq_online)
+				class->rq_online(rq);
+		}
+	}
+}
+
+static void set_rq_offline(struct rq *rq)
+{
+	if (rq->online) {
+		const struct sched_class *class;
+
+		for_each_class(class) {
+			if (class->rq_offline)
+				class->rq_offline(rq);
+		}
+
+		cpumask_clear_cpu(rq->cpu, rq->rd->online);
+		rq->online = 0;
+	}
+}
+
+/*
+ * migration_call - callback that gets triggered when a CPU is added.
+ * Here we can start up the necessary migration thread for the new CPU.
+ */
+static int __cpuinit
+migration_call(struct notifier_block *nfb, unsigned long action, void *hcpu)
+{
+	int cpu = (long)hcpu;
+	unsigned long flags;
+	struct rq *rq = cpu_rq(cpu);
+
+	switch (action & ~CPU_TASKS_FROZEN) {
+
+	case CPU_UP_PREPARE:
+		rq->calc_load_update = calc_load_update;
+		break;
+
+	case CPU_ONLINE:
+		/* Update our root-domain */
+		raw_spin_lock_irqsave(&rq->lock, flags);
+		if (rq->rd) {
+			BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span));
+
+			set_rq_online(rq);
+		}
+		raw_spin_unlock_irqrestore(&rq->lock, flags);
+		break;
+
+#ifdef CONFIG_HOTPLUG_CPU
+	case CPU_DYING:
+		sched_ttwu_pending();
+		/* Update our root-domain */
+		raw_spin_lock_irqsave(&rq->lock, flags);
+		if (rq->rd) {
+			BUG_ON(!cpumask_test_cpu(cpu, rq->rd->span));
+			set_rq_offline(rq);
+		}
+		migrate_tasks(cpu);
+		BUG_ON(rq->nr_running != 1); /* the migration thread */
+		raw_spin_unlock_irqrestore(&rq->lock, flags);
+
+		migrate_nr_uninterruptible(rq);
+		calc_global_load_remove(rq);
+		break;
+#endif
+	}
+
+	update_max_interval();
+
+	return NOTIFY_OK;
+}
+
+/*
+ * Register at high priority so that task migration (migrate_all_tasks)
+ * happens before everything else.  This has to be lower priority than
+ * the notifier in the perf_event subsystem, though.
+ */
+static struct notifier_block __cpuinitdata migration_notifier = {
+	.notifier_call = migration_call,
+	.priority = CPU_PRI_MIGRATION,
+};
+
+static int __cpuinit sched_cpu_active(struct notifier_block *nfb,
+				      unsigned long action, void *hcpu)
+{
+	switch (action & ~CPU_TASKS_FROZEN) {
+	case CPU_ONLINE:
+	case CPU_DOWN_FAILED:
+		set_cpu_active((long)hcpu, true);
+		return NOTIFY_OK;
+	default:
+		return NOTIFY_DONE;
+	}
+}
+
+static int __cpuinit sched_cpu_inactive(struct notifier_block *nfb,
+					unsigned long action, void *hcpu)
+{
+	switch (action & ~CPU_TASKS_FROZEN) {
+	case CPU_DOWN_PREPARE:
+		set_cpu_active((long)hcpu, false);
+		return NOTIFY_OK;
+	default:
+		return NOTIFY_DONE;
+	}
+}
+
+static int __init migration_init(void)
+{
+	void *cpu = (void *)(long)smp_processor_id();
+	int err;
+
+	/* Initialize migration for the boot CPU */
+	err = migration_call(&migration_notifier, CPU_UP_PREPARE, cpu);
+	BUG_ON(err == NOTIFY_BAD);
+	migration_call(&migration_notifier, CPU_ONLINE, cpu);
+	register_cpu_notifier(&migration_notifier);
+
+	/* Register cpu active notifiers */
+	cpu_notifier(sched_cpu_active, CPU_PRI_SCHED_ACTIVE);
+	cpu_notifier(sched_cpu_inactive, CPU_PRI_SCHED_INACTIVE);
+
+	return 0;
+}
+early_initcall(migration_init);
+#endif
+
+#ifdef CONFIG_SMP
+
+static cpumask_var_t sched_domains_tmpmask; /* sched_domains_mutex */
+
+#ifdef CONFIG_SCHED_DEBUG
+
+static __read_mostly int sched_domain_debug_enabled;
+
+static int __init sched_domain_debug_setup(char *str)
+{
+	sched_domain_debug_enabled = 1;
+
+	return 0;
+}
+early_param("sched_debug", sched_domain_debug_setup);
+
+static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
+				  struct cpumask *groupmask)
+{
+	struct sched_group *group = sd->groups;
+	char str[256];
+
+	cpulist_scnprintf(str, sizeof(str), sched_domain_span(sd));
+	cpumask_clear(groupmask);
+
+	printk(KERN_DEBUG "%*s domain %d: ", level, "", level);
+
+	if (!(sd->flags & SD_LOAD_BALANCE)) {
+		printk("does not load-balance\n");
+		if (sd->parent)
+			printk(KERN_ERR "ERROR: !SD_LOAD_BALANCE domain"
+					" has parent");
+		return -1;
+	}
+
+	printk(KERN_CONT "span %s level %s\n", str, sd->name);
+
+	if (!cpumask_test_cpu(cpu, sched_domain_span(sd))) {
+		printk(KERN_ERR "ERROR: domain->span does not contain "
+				"CPU%d\n", cpu);
+	}
+	if (!cpumask_test_cpu(cpu, sched_group_cpus(group))) {
+		printk(KERN_ERR "ERROR: domain->groups does not contain"
+				" CPU%d\n", cpu);
+	}
+
+	printk(KERN_DEBUG "%*s groups:", level + 1, "");
+	do {
+		if (!group) {
+			printk("\n");
+			printk(KERN_ERR "ERROR: group is NULL\n");
+			break;
+		}
+
+		if (!group->sgp->power) {
+			printk(KERN_CONT "\n");
+			printk(KERN_ERR "ERROR: domain->cpu_power not "
+					"set\n");
+			break;
+		}
+
+		if (!cpumask_weight(sched_group_cpus(group))) {
+			printk(KERN_CONT "\n");
+			printk(KERN_ERR "ERROR: empty group\n");
+			break;
+		}
+
+		if (cpumask_intersects(groupmask, sched_group_cpus(group))) {
+			printk(KERN_CONT "\n");
+			printk(KERN_ERR "ERROR: repeated CPUs\n");
+			break;
+		}
+
+		cpumask_or(groupmask, groupmask, sched_group_cpus(group));
+
+		cpulist_scnprintf(str, sizeof(str), sched_group_cpus(group));
+
+		printk(KERN_CONT " %s", str);
+		if (group->sgp->power != SCHED_POWER_SCALE) {
+			printk(KERN_CONT " (cpu_power = %d)",
+				group->sgp->power);
+		}
+
+		group = group->next;
+	} while (group != sd->groups);
+	printk(KERN_CONT "\n");
+
+	if (!cpumask_equal(sched_domain_span(sd), groupmask))
+		printk(KERN_ERR "ERROR: groups don't span domain->span\n");
+
+	if (sd->parent &&
+	    !cpumask_subset(groupmask, sched_domain_span(sd->parent)))
+		printk(KERN_ERR "ERROR: parent span is not a superset "
+			"of domain->span\n");
+	return 0;
+}
+
+static void sched_domain_debug(struct sched_domain *sd, int cpu)
+{
+	int level = 0;
+
+	if (!sched_domain_debug_enabled)
+		return;
+
+	if (!sd) {
+		printk(KERN_DEBUG "CPU%d attaching NULL sched-domain.\n", cpu);
+		return;
+	}
+
+	printk(KERN_DEBUG "CPU%d attaching sched-domain:\n", cpu);
+
+	for (;;) {
+		if (sched_domain_debug_one(sd, cpu, level, sched_domains_tmpmask))
+			break;
+		level++;
+		sd = sd->parent;
+		if (!sd)
+			break;
+	}
+}
+#else /* !CONFIG_SCHED_DEBUG */
+# define sched_domain_debug(sd, cpu) do { } while (0)
+#endif /* CONFIG_SCHED_DEBUG */
+
+static int sd_degenerate(struct sched_domain *sd)
+{
+	if (cpumask_weight(sched_domain_span(sd)) == 1)
+		return 1;
+
+	/* Following flags need at least 2 groups */
+	if (sd->flags & (SD_LOAD_BALANCE |
+			 SD_BALANCE_NEWIDLE |
+			 SD_BALANCE_FORK |
+			 SD_BALANCE_EXEC |
+			 SD_SHARE_CPUPOWER |
+			 SD_SHARE_PKG_RESOURCES)) {
+		if (sd->groups != sd->groups->next)
+			return 0;
+	}
+
+	/* Following flags don't use groups */
+	if (sd->flags & (SD_WAKE_AFFINE))
+		return 0;
+
+	return 1;
+}
+
+static int
+sd_parent_degenerate(struct sched_domain *sd, struct sched_domain *parent)
+{
+	unsigned long cflags = sd->flags, pflags = parent->flags;
+
+	if (sd_degenerate(parent))
+		return 1;
+
+	if (!cpumask_equal(sched_domain_span(sd), sched_domain_span(parent)))
+		return 0;
+
+	/* Flags needing groups don't count if only 1 group in parent */
+	if (parent->groups == parent->groups->next) {
+		pflags &= ~(SD_LOAD_BALANCE |
+				SD_BALANCE_NEWIDLE |
+				SD_BALANCE_FORK |
+				SD_BALANCE_EXEC |
+				SD_SHARE_CPUPOWER |
+				SD_SHARE_PKG_RESOURCES);
+		if (nr_node_ids == 1)
+			pflags &= ~SD_SERIALIZE;
+	}
+	if (~cflags & pflags)
+		return 0;
+
+	return 1;
+}
+
+static void free_rootdomain(struct rcu_head *rcu)
+{
+	struct root_domain *rd = container_of(rcu, struct root_domain, rcu);
+
+	cpupri_cleanup(&rd->cpupri);
+	free_cpumask_var(rd->rto_mask);
+	free_cpumask_var(rd->online);
+	free_cpumask_var(rd->span);
+	kfree(rd);
+}
+
+static void rq_attach_root(struct rq *rq, struct root_domain *rd)
+{
+	struct root_domain *old_rd = NULL;
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&rq->lock, flags);
+
+	if (rq->rd) {
+		old_rd = rq->rd;
+
+		if (cpumask_test_cpu(rq->cpu, old_rd->online))
+			set_rq_offline(rq);
+
+		cpumask_clear_cpu(rq->cpu, old_rd->span);
+
+		/*
+		 * If we dont want to free the old_rt yet then
+		 * set old_rd to NULL to skip the freeing later
+		 * in this function:
+		 */
+		if (!atomic_dec_and_test(&old_rd->refcount))
+			old_rd = NULL;
+	}
+
+	atomic_inc(&rd->refcount);
+	rq->rd = rd;
+
+	cpumask_set_cpu(rq->cpu, rd->span);
+	if (cpumask_test_cpu(rq->cpu, cpu_active_mask))
+		set_rq_online(rq);
+
+	raw_spin_unlock_irqrestore(&rq->lock, flags);
+
+	if (old_rd)
+		call_rcu_sched(&old_rd->rcu, free_rootdomain);
+}
+
+static int init_rootdomain(struct root_domain *rd)
+{
+	memset(rd, 0, sizeof(*rd));
+
+	if (!alloc_cpumask_var(&rd->span, GFP_KERNEL))
+		goto out;
+	if (!alloc_cpumask_var(&rd->online, GFP_KERNEL))
+		goto free_span;
+	if (!alloc_cpumask_var(&rd->rto_mask, GFP_KERNEL))
+		goto free_online;
+
+	if (cpupri_init(&rd->cpupri) != 0)
+		goto free_rto_mask;
+	return 0;
+
+free_rto_mask:
+	free_cpumask_var(rd->rto_mask);
+free_online:
+	free_cpumask_var(rd->online);
+free_span:
+	free_cpumask_var(rd->span);
+out:
+	return -ENOMEM;
+}
+
+/*
+ * By default the system creates a single root-domain with all cpus as
+ * members (mimicking the global state we have today).
+ */
+struct root_domain def_root_domain;
+
+static void init_defrootdomain(void)
+{
+	init_rootdomain(&def_root_domain);
+
+	atomic_set(&def_root_domain.refcount, 1);
+}
+
+static struct root_domain *alloc_rootdomain(void)
+{
+	struct root_domain *rd;
+
+	rd = kmalloc(sizeof(*rd), GFP_KERNEL);
+	if (!rd)
+		return NULL;
+
+	if (init_rootdomain(rd) != 0) {
+		kfree(rd);
+		return NULL;
+	}
+
+	return rd;
+}
+
+static void free_sched_groups(struct sched_group *sg, int free_sgp)
+{
+	struct sched_group *tmp, *first;
+
+	if (!sg)
+		return;
+
+	first = sg;
+	do {
+		tmp = sg->next;
+
+		if (free_sgp && atomic_dec_and_test(&sg->sgp->ref))
+			kfree(sg->sgp);
+
+		kfree(sg);
+		sg = tmp;
+	} while (sg != first);
+}
+
+static void free_sched_domain(struct rcu_head *rcu)
+{
+	struct sched_domain *sd = container_of(rcu, struct sched_domain, rcu);
+
+	/*
+	 * If its an overlapping domain it has private groups, iterate and
+	 * nuke them all.
+	 */
+	if (sd->flags & SD_OVERLAP) {
+		free_sched_groups(sd->groups, 1);
+	} else if (atomic_dec_and_test(&sd->groups->ref)) {
+		kfree(sd->groups->sgp);
+		kfree(sd->groups);
+	}
+	kfree(sd);
+}
+
+static void destroy_sched_domain(struct sched_domain *sd, int cpu)
+{
+	call_rcu(&sd->rcu, free_sched_domain);
+}
+
+static void destroy_sched_domains(struct sched_domain *sd, int cpu)
+{
+	for (; sd; sd = sd->parent)
+		destroy_sched_domain(sd, cpu);
+}
+
+/*
+ * Keep a special pointer to the highest sched_domain that has
+ * SD_SHARE_PKG_RESOURCE set (Last Level Cache Domain) for this
+ * allows us to avoid some pointer chasing select_idle_sibling().
+ *
+ * Also keep a unique ID per domain (we use the first cpu number in
+ * the cpumask of the domain), this allows us to quickly tell if
+ * two cpus are in the same cache domain, see ttwu_share_cache().
+ */
+DEFINE_PER_CPU(struct sched_domain *, sd_llc);
+DEFINE_PER_CPU(int, sd_llc_id);
+
+static void update_top_cache_domain(int cpu)
+{
+	struct sched_domain *sd;
+	int id = cpu;
+
+	sd = highest_flag_domain(cpu, SD_SHARE_PKG_RESOURCES);
+	if (sd)
+		id = cpumask_first(sched_domain_span(sd));
+
+	rcu_assign_pointer(per_cpu(sd_llc, cpu), sd);
+	per_cpu(sd_llc_id, cpu) = id;
+}
+
+/*
+ * Attach the domain 'sd' to 'cpu' as its base domain. Callers must
+ * hold the hotplug lock.
+ */
+static void
+cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu)
+{
+	struct rq *rq = cpu_rq(cpu);
+	struct sched_domain *tmp;
+
+	/* Remove the sched domains which do not contribute to scheduling. */
+	for (tmp = sd; tmp; ) {
+		struct sched_domain *parent = tmp->parent;
+		if (!parent)
+			break;
+
+		if (sd_parent_degenerate(tmp, parent)) {
+			tmp->parent = parent->parent;
+			if (parent->parent)
+				parent->parent->child = tmp;
+			destroy_sched_domain(parent, cpu);
+		} else
+			tmp = tmp->parent;
+	}
+
+	if (sd && sd_degenerate(sd)) {
+		tmp = sd;
+		sd = sd->parent;
+		destroy_sched_domain(tmp, cpu);
+		if (sd)
+			sd->child = NULL;
+	}
+
+	sched_domain_debug(sd, cpu);
+
+	rq_attach_root(rq, rd);
+	tmp = rq->sd;
+	rcu_assign_pointer(rq->sd, sd);
+	destroy_sched_domains(tmp, cpu);
+
+	update_top_cache_domain(cpu);
+}
+
+/* cpus with isolated domains */
+static cpumask_var_t cpu_isolated_map;
+
+/* Setup the mask of cpus configured for isolated domains */
+static int __init isolated_cpu_setup(char *str)
+{
+	alloc_bootmem_cpumask_var(&cpu_isolated_map);
+	cpulist_parse(str, cpu_isolated_map);
+	return 1;
+}
+
+__setup("isolcpus=", isolated_cpu_setup);
+
+#ifdef CONFIG_NUMA
+
+/**
+ * find_next_best_node - find the next node to include in a sched_domain
+ * @node: node whose sched_domain we're building
+ * @used_nodes: nodes already in the sched_domain
+ *
+ * Find the next node to include in a given scheduling domain. Simply
+ * finds the closest node not already in the @used_nodes map.
+ *
+ * Should use nodemask_t.
+ */
+static int find_next_best_node(int node, nodemask_t *used_nodes)
+{
+	int i, n, val, min_val, best_node = -1;
+
+	min_val = INT_MAX;
+
+	for (i = 0; i < nr_node_ids; i++) {
+		/* Start at @node */
+		n = (node + i) % nr_node_ids;
+
+		if (!nr_cpus_node(n))
+			continue;
+
+		/* Skip already used nodes */
+		if (node_isset(n, *used_nodes))
+			continue;
+
+		/* Simple min distance search */
+		val = node_distance(node, n);
+
+		if (val < min_val) {
+			min_val = val;
+			best_node = n;
+		}
+	}
+
+	if (best_node != -1)
+		node_set(best_node, *used_nodes);
+	return best_node;
+}
+
+/**
+ * sched_domain_node_span - get a cpumask for a node's sched_domain
+ * @node: node whose cpumask we're constructing
+ * @span: resulting cpumask
+ *
+ * Given a node, construct a good cpumask for its sched_domain to span. It
+ * should be one that prevents unnecessary balancing, but also spreads tasks
+ * out optimally.
+ */
+static void sched_domain_node_span(int node, struct cpumask *span)
+{
+	nodemask_t used_nodes;
+	int i;
+
+	cpumask_clear(span);
+	nodes_clear(used_nodes);
+
+	cpumask_or(span, span, cpumask_of_node(node));
+	node_set(node, used_nodes);
+
+	for (i = 1; i < SD_NODES_PER_DOMAIN; i++) {
+		int next_node = find_next_best_node(node, &used_nodes);
+		if (next_node < 0)
+			break;
+		cpumask_or(span, span, cpumask_of_node(next_node));
+	}
+}
+
+static const struct cpumask *cpu_node_mask(int cpu)
+{
+	lockdep_assert_held(&sched_domains_mutex);
+
+	sched_domain_node_span(cpu_to_node(cpu), sched_domains_tmpmask);
+
+	return sched_domains_tmpmask;
+}
+
+static const struct cpumask *cpu_allnodes_mask(int cpu)
+{
+	return cpu_possible_mask;
+}
+#endif /* CONFIG_NUMA */
+
+static const struct cpumask *cpu_cpu_mask(int cpu)
+{
+	return cpumask_of_node(cpu_to_node(cpu));
+}
+
+int sched_smt_power_savings = 0, sched_mc_power_savings = 0;
+
+struct sd_data {
+	struct sched_domain **__percpu sd;
+	struct sched_group **__percpu sg;
+	struct sched_group_power **__percpu sgp;
+};
+
+struct s_data {
+	struct sched_domain ** __percpu sd;
+	struct root_domain	*rd;
+};
+
+enum s_alloc {
+	sa_rootdomain,
+	sa_sd,
+	sa_sd_storage,
+	sa_none,
+};
+
+struct sched_domain_topology_level;
+
+typedef struct sched_domain *(*sched_domain_init_f)(struct sched_domain_topology_level *tl, int cpu);
+typedef const struct cpumask *(*sched_domain_mask_f)(int cpu);
+
+#define SDTL_OVERLAP	0x01
+
+struct sched_domain_topology_level {
+	sched_domain_init_f init;
+	sched_domain_mask_f mask;
+	int		    flags;
+	struct sd_data      data;
+};
+
+static int
+build_overlap_sched_groups(struct sched_domain *sd, int cpu)
+{
+	struct sched_group *first = NULL, *last = NULL, *groups = NULL, *sg;
+	const struct cpumask *span = sched_domain_span(sd);
+	struct cpumask *covered = sched_domains_tmpmask;
+	struct sd_data *sdd = sd->private;
+	struct sched_domain *child;
+	int i;
+
+	cpumask_clear(covered);
+
+	for_each_cpu(i, span) {
+		struct cpumask *sg_span;
+
+		if (cpumask_test_cpu(i, covered))
+			continue;
+
+		sg = kzalloc_node(sizeof(struct sched_group) + cpumask_size(),
+				GFP_KERNEL, cpu_to_node(cpu));
+
+		if (!sg)
+			goto fail;
+
+		sg_span = sched_group_cpus(sg);
+
+		child = *per_cpu_ptr(sdd->sd, i);
+		if (child->child) {
+			child = child->child;
+			cpumask_copy(sg_span, sched_domain_span(child));
+		} else
+			cpumask_set_cpu(i, sg_span);
+
+		cpumask_or(covered, covered, sg_span);
+
+		sg->sgp = *per_cpu_ptr(sdd->sgp, cpumask_first(sg_span));
+		atomic_inc(&sg->sgp->ref);
+
+		if (cpumask_test_cpu(cpu, sg_span))
+			groups = sg;
+
+		if (!first)
+			first = sg;
+		if (last)
+			last->next = sg;
+		last = sg;
+		last->next = first;
+	}
+	sd->groups = groups;
+
+	return 0;
+
+fail:
+	free_sched_groups(first, 0);
+
+	return -ENOMEM;
+}
+
+static int get_group(int cpu, struct sd_data *sdd, struct sched_group **sg)
+{
+	struct sched_domain *sd = *per_cpu_ptr(sdd->sd, cpu);
+	struct sched_domain *child = sd->child;
+
+	if (child)
+		cpu = cpumask_first(sched_domain_span(child));
+
+	if (sg) {
+		*sg = *per_cpu_ptr(sdd->sg, cpu);
+		(*sg)->sgp = *per_cpu_ptr(sdd->sgp, cpu);
+		atomic_set(&(*sg)->sgp->ref, 1); /* for claim_allocations */
+	}
+
+	return cpu;
+}
+
+/*
+ * build_sched_groups will build a circular linked list of the groups
+ * covered by the given span, and will set each group's ->cpumask correctly,
+ * and ->cpu_power to 0.
+ *
+ * Assumes the sched_domain tree is fully constructed
+ */
+static int
+build_sched_groups(struct sched_domain *sd, int cpu)
+{
+	struct sched_group *first = NULL, *last = NULL;
+	struct sd_data *sdd = sd->private;
+	const struct cpumask *span = sched_domain_span(sd);
+	struct cpumask *covered;
+	int i;
+
+	get_group(cpu, sdd, &sd->groups);
+	atomic_inc(&sd->groups->ref);
+
+	if (cpu != cpumask_first(sched_domain_span(sd)))
+		return 0;
+
+	lockdep_assert_held(&sched_domains_mutex);
+	covered = sched_domains_tmpmask;
+
+	cpumask_clear(covered);
+
+	for_each_cpu(i, span) {
+		struct sched_group *sg;
+		int group = get_group(i, sdd, &sg);
+		int j;
+
+		if (cpumask_test_cpu(i, covered))
+			continue;
+
+		cpumask_clear(sched_group_cpus(sg));
+		sg->sgp->power = 0;
+
+		for_each_cpu(j, span) {
+			if (get_group(j, sdd, NULL) != group)
+				continue;
+
+			cpumask_set_cpu(j, covered);
+			cpumask_set_cpu(j, sched_group_cpus(sg));
+		}
+
+		if (!first)
+			first = sg;
+		if (last)
+			last->next = sg;
+		last = sg;
+	}
+	last->next = first;
+
+	return 0;
+}
+
+/*
+ * Initialize sched groups cpu_power.
+ *
+ * cpu_power indicates the capacity of sched group, which is used while
+ * distributing the load between different sched groups in a sched domain.
+ * Typically cpu_power for all the groups in a sched domain will be same unless
+ * there are asymmetries in the topology. If there are asymmetries, group
+ * having more cpu_power will pickup more load compared to the group having
+ * less cpu_power.
+ */
+static void init_sched_groups_power(int cpu, struct sched_domain *sd)
+{
+	struct sched_group *sg = sd->groups;
+
+	WARN_ON(!sd || !sg);
+
+	do {
+		sg->group_weight = cpumask_weight(sched_group_cpus(sg));
+		sg = sg->next;
+	} while (sg != sd->groups);
+
+	if (cpu != group_first_cpu(sg))
+		return;
+
+	update_group_power(sd, cpu);
+	atomic_set(&sg->sgp->nr_busy_cpus, sg->group_weight);
+}
+
+int __weak arch_sd_sibling_asym_packing(void)
+{
+       return 0*SD_ASYM_PACKING;
+}
+
+/*
+ * Initializers for schedule domains
+ * Non-inlined to reduce accumulated stack pressure in build_sched_domains()
+ */
+
+#ifdef CONFIG_SCHED_DEBUG
+# define SD_INIT_NAME(sd, type)		sd->name = #type
+#else
+# define SD_INIT_NAME(sd, type)		do { } while (0)
+#endif
+
+#define SD_INIT_FUNC(type)						\
+static noinline struct sched_domain *					\
+sd_init_##type(struct sched_domain_topology_level *tl, int cpu) 	\
+{									\
+	struct sched_domain *sd = *per_cpu_ptr(tl->data.sd, cpu);	\
+	*sd = SD_##type##_INIT;						\
+	SD_INIT_NAME(sd, type);						\
+	sd->private = &tl->data;					\
+	return sd;							\
+}
+
+SD_INIT_FUNC(CPU)
+#ifdef CONFIG_NUMA
+ SD_INIT_FUNC(ALLNODES)
+ SD_INIT_FUNC(NODE)
+#endif
+#ifdef CONFIG_SCHED_SMT
+ SD_INIT_FUNC(SIBLING)
+#endif
+#ifdef CONFIG_SCHED_MC
+ SD_INIT_FUNC(MC)
+#endif
+#ifdef CONFIG_SCHED_BOOK
+ SD_INIT_FUNC(BOOK)
+#endif
+
+static int default_relax_domain_level = -1;
+int sched_domain_level_max;
+
+static int __init setup_relax_domain_level(char *str)
+{
+	unsigned long val;
+
+	val = simple_strtoul(str, NULL, 0);
+	if (val < sched_domain_level_max)
+		default_relax_domain_level = val;
+
+	return 1;
+}
+__setup("relax_domain_level=", setup_relax_domain_level);
+
+static void set_domain_attribute(struct sched_domain *sd,
+				 struct sched_domain_attr *attr)
+{
+	int request;
+
+	if (!attr || attr->relax_domain_level < 0) {
+		if (default_relax_domain_level < 0)
+			return;
+		else
+			request = default_relax_domain_level;
+	} else
+		request = attr->relax_domain_level;
+	if (request < sd->level) {
+		/* turn off idle balance on this domain */
+		sd->flags &= ~(SD_BALANCE_WAKE|SD_BALANCE_NEWIDLE);
+	} else {
+		/* turn on idle balance on this domain */
+		sd->flags |= (SD_BALANCE_WAKE|SD_BALANCE_NEWIDLE);
+	}
+}
+
+static void __sdt_free(const struct cpumask *cpu_map);
+static int __sdt_alloc(const struct cpumask *cpu_map);
+
+static void __free_domain_allocs(struct s_data *d, enum s_alloc what,
+				 const struct cpumask *cpu_map)
+{
+	switch (what) {
+	case sa_rootdomain:
+		if (!atomic_read(&d->rd->refcount))
+			free_rootdomain(&d->rd->rcu); /* fall through */
+	case sa_sd:
+		free_percpu(d->sd); /* fall through */
+	case sa_sd_storage:
+		__sdt_free(cpu_map); /* fall through */
+	case sa_none:
+		break;
+	}
+}
+
+static enum s_alloc __visit_domain_allocation_hell(struct s_data *d,
+						   const struct cpumask *cpu_map)
+{
+	memset(d, 0, sizeof(*d));
+
+	if (__sdt_alloc(cpu_map))
+		return sa_sd_storage;
+	d->sd = alloc_percpu(struct sched_domain *);
+	if (!d->sd)
+		return sa_sd_storage;
+	d->rd = alloc_rootdomain();
+	if (!d->rd)
+		return sa_sd;
+	return sa_rootdomain;
+}
+
+/*
+ * NULL the sd_data elements we've used to build the sched_domain and
+ * sched_group structure so that the subsequent __free_domain_allocs()
+ * will not free the data we're using.
+ */
+static void claim_allocations(int cpu, struct sched_domain *sd)
+{
+	struct sd_data *sdd = sd->private;
+
+	WARN_ON_ONCE(*per_cpu_ptr(sdd->sd, cpu) != sd);
+	*per_cpu_ptr(sdd->sd, cpu) = NULL;
+
+	if (atomic_read(&(*per_cpu_ptr(sdd->sg, cpu))->ref))
+		*per_cpu_ptr(sdd->sg, cpu) = NULL;
+
+	if (atomic_read(&(*per_cpu_ptr(sdd->sgp, cpu))->ref))
+		*per_cpu_ptr(sdd->sgp, cpu) = NULL;
+}
+
+#ifdef CONFIG_SCHED_SMT
+static const struct cpumask *cpu_smt_mask(int cpu)
+{
+	return topology_thread_cpumask(cpu);
+}
+#endif
+
+/*
+ * Topology list, bottom-up.
+ */
+static struct sched_domain_topology_level default_topology[] = {
+#ifdef CONFIG_SCHED_SMT
+	{ sd_init_SIBLING, cpu_smt_mask, },
+#endif
+#ifdef CONFIG_SCHED_MC
+	{ sd_init_MC, cpu_coregroup_mask, },
+#endif
+#ifdef CONFIG_SCHED_BOOK
+	{ sd_init_BOOK, cpu_book_mask, },
+#endif
+	{ sd_init_CPU, cpu_cpu_mask, },
+#ifdef CONFIG_NUMA
+	{ sd_init_NODE, cpu_node_mask, SDTL_OVERLAP, },
+	{ sd_init_ALLNODES, cpu_allnodes_mask, },
+#endif
+	{ NULL, },
+};
+
+static struct sched_domain_topology_level *sched_domain_topology = default_topology;
+
+static int __sdt_alloc(const struct cpumask *cpu_map)
+{
+	struct sched_domain_topology_level *tl;
+	int j;
+
+	for (tl = sched_domain_topology; tl->init; tl++) {
+		struct sd_data *sdd = &tl->data;
+
+		sdd->sd = alloc_percpu(struct sched_domain *);
+		if (!sdd->sd)
+			return -ENOMEM;
+
+		sdd->sg = alloc_percpu(struct sched_group *);
+		if (!sdd->sg)
+			return -ENOMEM;
+
+		sdd->sgp = alloc_percpu(struct sched_group_power *);
+		if (!sdd->sgp)
+			return -ENOMEM;
+
+		for_each_cpu(j, cpu_map) {
+			struct sched_domain *sd;
+			struct sched_group *sg;
+			struct sched_group_power *sgp;
+
+		       	sd = kzalloc_node(sizeof(struct sched_domain) + cpumask_size(),
+					GFP_KERNEL, cpu_to_node(j));
+			if (!sd)
+				return -ENOMEM;
+
+			*per_cpu_ptr(sdd->sd, j) = sd;
+
+			sg = kzalloc_node(sizeof(struct sched_group) + cpumask_size(),
+					GFP_KERNEL, cpu_to_node(j));
+			if (!sg)
+				return -ENOMEM;
+
+			*per_cpu_ptr(sdd->sg, j) = sg;
+
+			sgp = kzalloc_node(sizeof(struct sched_group_power),
+					GFP_KERNEL, cpu_to_node(j));
+			if (!sgp)
+				return -ENOMEM;
+
+			*per_cpu_ptr(sdd->sgp, j) = sgp;
+		}
+	}
+
+	return 0;
+}
+
+static void __sdt_free(const struct cpumask *cpu_map)
+{
+	struct sched_domain_topology_level *tl;
+	int j;
+
+	for (tl = sched_domain_topology; tl->init; tl++) {
+		struct sd_data *sdd = &tl->data;
+
+		for_each_cpu(j, cpu_map) {
+			struct sched_domain *sd = *per_cpu_ptr(sdd->sd, j);
+			if (sd && (sd->flags & SD_OVERLAP))
+				free_sched_groups(sd->groups, 0);
+			kfree(*per_cpu_ptr(sdd->sd, j));
+			kfree(*per_cpu_ptr(sdd->sg, j));
+			kfree(*per_cpu_ptr(sdd->sgp, j));
+		}
+		free_percpu(sdd->sd);
+		free_percpu(sdd->sg);
+		free_percpu(sdd->sgp);
+	}
+}
+
+struct sched_domain *build_sched_domain(struct sched_domain_topology_level *tl,
+		struct s_data *d, const struct cpumask *cpu_map,
+		struct sched_domain_attr *attr, struct sched_domain *child,
+		int cpu)
+{
+	struct sched_domain *sd = tl->init(tl, cpu);
+	if (!sd)
+		return child;
+
+	set_domain_attribute(sd, attr);
+	cpumask_and(sched_domain_span(sd), cpu_map, tl->mask(cpu));
+	if (child) {
+		sd->level = child->level + 1;
+		sched_domain_level_max = max(sched_domain_level_max, sd->level);
+		child->parent = sd;
+	}
+	sd->child = child;
+
+	return sd;
+}
+
+/*
+ * Build sched domains for a given set of cpus and attach the sched domains
+ * to the individual cpus
+ */
+static int build_sched_domains(const struct cpumask *cpu_map,
+			       struct sched_domain_attr *attr)
+{
+	enum s_alloc alloc_state = sa_none;
+	struct sched_domain *sd;
+	struct s_data d;
+	int i, ret = -ENOMEM;
+
+	alloc_state = __visit_domain_allocation_hell(&d, cpu_map);
+	if (alloc_state != sa_rootdomain)
+		goto error;
+
+	/* Set up domains for cpus specified by the cpu_map. */
+	for_each_cpu(i, cpu_map) {
+		struct sched_domain_topology_level *tl;
+
+		sd = NULL;
+		for (tl = sched_domain_topology; tl->init; tl++) {
+			sd = build_sched_domain(tl, &d, cpu_map, attr, sd, i);
+			if (tl->flags & SDTL_OVERLAP || sched_feat(FORCE_SD_OVERLAP))
+				sd->flags |= SD_OVERLAP;
+			if (cpumask_equal(cpu_map, sched_domain_span(sd)))
+				break;
+		}
+
+		while (sd->child)
+			sd = sd->child;
+
+		*per_cpu_ptr(d.sd, i) = sd;
+	}
+
+	/* Build the groups for the domains */
+	for_each_cpu(i, cpu_map) {
+		for (sd = *per_cpu_ptr(d.sd, i); sd; sd = sd->parent) {
+			sd->span_weight = cpumask_weight(sched_domain_span(sd));
+			if (sd->flags & SD_OVERLAP) {
+				if (build_overlap_sched_groups(sd, i))
+					goto error;
+			} else {
+				if (build_sched_groups(sd, i))
+					goto error;
+			}
+		}
+	}
+
+	/* Calculate CPU power for physical packages and nodes */
+	for (i = nr_cpumask_bits-1; i >= 0; i--) {
+		if (!cpumask_test_cpu(i, cpu_map))
+			continue;
+
+		for (sd = *per_cpu_ptr(d.sd, i); sd; sd = sd->parent) {
+			claim_allocations(i, sd);
+			init_sched_groups_power(i, sd);
+		}
+	}
+
+	/* Attach the domains */
+	rcu_read_lock();
+	for_each_cpu(i, cpu_map) {
+		sd = *per_cpu_ptr(d.sd, i);
+		cpu_attach_domain(sd, d.rd, i);
+	}
+	rcu_read_unlock();
+
+	ret = 0;
+error:
+	__free_domain_allocs(&d, alloc_state, cpu_map);
+	return ret;
+}
+
+static cpumask_var_t *doms_cur;	/* current sched domains */
+static int ndoms_cur;		/* number of sched domains in 'doms_cur' */
+static struct sched_domain_attr *dattr_cur;
+				/* attribues of custom domains in 'doms_cur' */
+
+/*
+ * Special case: If a kmalloc of a doms_cur partition (array of
+ * cpumask) fails, then fallback to a single sched domain,
+ * as determined by the single cpumask fallback_doms.
+ */
+static cpumask_var_t fallback_doms;
+
+/*
+ * arch_update_cpu_topology lets virtualized architectures update the
+ * cpu core maps. It is supposed to return 1 if the topology changed
+ * or 0 if it stayed the same.
+ */
+int __attribute__((weak)) arch_update_cpu_topology(void)
+{
+	return 0;
+}
+
+cpumask_var_t *alloc_sched_domains(unsigned int ndoms)
+{
+	int i;
+	cpumask_var_t *doms;
+
+	doms = kmalloc(sizeof(*doms) * ndoms, GFP_KERNEL);
+	if (!doms)
+		return NULL;
+	for (i = 0; i < ndoms; i++) {
+		if (!alloc_cpumask_var(&doms[i], GFP_KERNEL)) {
+			free_sched_domains(doms, i);
+			return NULL;
+		}
+	}
+	return doms;
+}
+
+void free_sched_domains(cpumask_var_t doms[], unsigned int ndoms)
+{
+	unsigned int i;
+	for (i = 0; i < ndoms; i++)
+		free_cpumask_var(doms[i]);
+	kfree(doms);
+}
+
+/*
+ * Set up scheduler domains and groups. Callers must hold the hotplug lock.
+ * For now this just excludes isolated cpus, but could be used to
+ * exclude other special cases in the future.
+ */
+static int init_sched_domains(const struct cpumask *cpu_map)
+{
+	int err;
+
+	arch_update_cpu_topology();
+	ndoms_cur = 1;
+	doms_cur = alloc_sched_domains(ndoms_cur);
+	if (!doms_cur)
+		doms_cur = &fallback_doms;
+	cpumask_andnot(doms_cur[0], cpu_map, cpu_isolated_map);
+	dattr_cur = NULL;
+	err = build_sched_domains(doms_cur[0], NULL);
+	register_sched_domain_sysctl();
+
+	return err;
+}
+
+/*
+ * Detach sched domains from a group of cpus specified in cpu_map
+ * These cpus will now be attached to the NULL domain
+ */
+static void detach_destroy_domains(const struct cpumask *cpu_map)
+{
+	int i;
+
+	rcu_read_lock();
+	for_each_cpu(i, cpu_map)
+		cpu_attach_domain(NULL, &def_root_domain, i);
+	rcu_read_unlock();
+}
+
+/* handle null as "default" */
+static int dattrs_equal(struct sched_domain_attr *cur, int idx_cur,
+			struct sched_domain_attr *new, int idx_new)
+{
+	struct sched_domain_attr tmp;
+
+	/* fast path */
+	if (!new && !cur)
+		return 1;
+
+	tmp = SD_ATTR_INIT;
+	return !memcmp(cur ? (cur + idx_cur) : &tmp,
+			new ? (new + idx_new) : &tmp,
+			sizeof(struct sched_domain_attr));
+}
+
+/*
+ * Partition sched domains as specified by the 'ndoms_new'
+ * cpumasks in the array doms_new[] of cpumasks. This compares
+ * doms_new[] to the current sched domain partitioning, doms_cur[].
+ * It destroys each deleted domain and builds each new domain.
+ *
+ * 'doms_new' is an array of cpumask_var_t's of length 'ndoms_new'.
+ * The masks don't intersect (don't overlap.) We should setup one
+ * sched domain for each mask. CPUs not in any of the cpumasks will
+ * not be load balanced. If the same cpumask appears both in the
+ * current 'doms_cur' domains and in the new 'doms_new', we can leave
+ * it as it is.
+ *
+ * The passed in 'doms_new' should be allocated using
+ * alloc_sched_domains.  This routine takes ownership of it and will
+ * free_sched_domains it when done with it. If the caller failed the
+ * alloc call, then it can pass in doms_new == NULL && ndoms_new == 1,
+ * and partition_sched_domains() will fallback to the single partition
+ * 'fallback_doms', it also forces the domains to be rebuilt.
+ *
+ * If doms_new == NULL it will be replaced with cpu_online_mask.
+ * ndoms_new == 0 is a special case for destroying existing domains,
+ * and it will not create the default domain.
+ *
+ * Call with hotplug lock held
+ */
+void partition_sched_domains(int ndoms_new, cpumask_var_t doms_new[],
+			     struct sched_domain_attr *dattr_new)
+{
+	int i, j, n;
+	int new_topology;
+
+	mutex_lock(&sched_domains_mutex);
+
+	/* always unregister in case we don't destroy any domains */
+	unregister_sched_domain_sysctl();
+
+	/* Let architecture update cpu core mappings. */
+	new_topology = arch_update_cpu_topology();
+
+	n = doms_new ? ndoms_new : 0;
+
+	/* Destroy deleted domains */
+	for (i = 0; i < ndoms_cur; i++) {
+		for (j = 0; j < n && !new_topology; j++) {
+			if (cpumask_equal(doms_cur[i], doms_new[j])
+			    && dattrs_equal(dattr_cur, i, dattr_new, j))
+				goto match1;
+		}
+		/* no match - a current sched domain not in new doms_new[] */
+		detach_destroy_domains(doms_cur[i]);
+match1:
+		;
+	}
+
+	if (doms_new == NULL) {
+		ndoms_cur = 0;
+		doms_new = &fallback_doms;
+		cpumask_andnot(doms_new[0], cpu_active_mask, cpu_isolated_map);
+		WARN_ON_ONCE(dattr_new);
+	}
+
+	/* Build new domains */
+	for (i = 0; i < ndoms_new; i++) {
+		for (j = 0; j < ndoms_cur && !new_topology; j++) {
+			if (cpumask_equal(doms_new[i], doms_cur[j])
+			    && dattrs_equal(dattr_new, i, dattr_cur, j))
+				goto match2;
+		}
+		/* no match - add a new doms_new */
+		build_sched_domains(doms_new[i], dattr_new ? dattr_new + i : NULL);
+match2:
+		;
+	}
+
+	/* Remember the new sched domains */
+	if (doms_cur != &fallback_doms)
+		free_sched_domains(doms_cur, ndoms_cur);
+	kfree(dattr_cur);	/* kfree(NULL) is safe */
+	doms_cur = doms_new;
+	dattr_cur = dattr_new;
+	ndoms_cur = ndoms_new;
+
+	register_sched_domain_sysctl();
+
+	mutex_unlock(&sched_domains_mutex);
+}
+
+#if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT)
+static void reinit_sched_domains(void)
+{
+	get_online_cpus();
+
+	/* Destroy domains first to force the rebuild */
+	partition_sched_domains(0, NULL, NULL);
+
+	rebuild_sched_domains();
+	put_online_cpus();
+}
+
+static ssize_t sched_power_savings_store(const char *buf, size_t count, int smt)
+{
+	unsigned int level = 0;
+
+	if (sscanf(buf, "%u", &level) != 1)
+		return -EINVAL;
+
+	/*
+	 * level is always be positive so don't check for
+	 * level < POWERSAVINGS_BALANCE_NONE which is 0
+	 * What happens on 0 or 1 byte write,
+	 * need to check for count as well?
+	 */
+
+	if (level >= MAX_POWERSAVINGS_BALANCE_LEVELS)
+		return -EINVAL;
+
+	if (smt)
+		sched_smt_power_savings = level;
+	else
+		sched_mc_power_savings = level;
+
+	reinit_sched_domains();
+
+	return count;
+}
+
+#ifdef CONFIG_SCHED_MC
+static ssize_t sched_mc_power_savings_show(struct device *dev,
+					   struct device_attribute *attr,
+					   char *buf)
+{
+	return sprintf(buf, "%u\n", sched_mc_power_savings);
+}
+static ssize_t sched_mc_power_savings_store(struct device *dev,
+					    struct device_attribute *attr,
+					    const char *buf, size_t count)
+{
+	return sched_power_savings_store(buf, count, 0);
+}
+static DEVICE_ATTR(sched_mc_power_savings, 0644,
+		   sched_mc_power_savings_show,
+		   sched_mc_power_savings_store);
+#endif
+
+#ifdef CONFIG_SCHED_SMT
+static ssize_t sched_smt_power_savings_show(struct device *dev,
+					    struct device_attribute *attr,
+					    char *buf)
+{
+	return sprintf(buf, "%u\n", sched_smt_power_savings);
+}
+static ssize_t sched_smt_power_savings_store(struct device *dev,
+					    struct device_attribute *attr,
+					     const char *buf, size_t count)
+{
+	return sched_power_savings_store(buf, count, 1);
+}
+static DEVICE_ATTR(sched_smt_power_savings, 0644,
+		   sched_smt_power_savings_show,
+		   sched_smt_power_savings_store);
+#endif
+
+int __init sched_create_sysfs_power_savings_entries(struct device *dev)
+{
+	int err = 0;
+
+#ifdef CONFIG_SCHED_SMT
+	if (smt_capable())
+		err = device_create_file(dev, &dev_attr_sched_smt_power_savings);
+#endif
+#ifdef CONFIG_SCHED_MC
+	if (!err && mc_capable())
+		err = device_create_file(dev, &dev_attr_sched_mc_power_savings);
+#endif
+	return err;
+}
+#endif /* CONFIG_SCHED_MC || CONFIG_SCHED_SMT */
+
+/*
+ * Update cpusets according to cpu_active mask.  If cpusets are
+ * disabled, cpuset_update_active_cpus() becomes a simple wrapper
+ * around partition_sched_domains().
+ */
+static int cpuset_cpu_active(struct notifier_block *nfb, unsigned long action,
+			     void *hcpu)
+{
+	switch (action & ~CPU_TASKS_FROZEN) {
+	case CPU_ONLINE:
+	case CPU_DOWN_FAILED:
+		cpuset_update_active_cpus();
+		return NOTIFY_OK;
+	default:
+		return NOTIFY_DONE;
+	}
+}
+
+static int cpuset_cpu_inactive(struct notifier_block *nfb, unsigned long action,
+			       void *hcpu)
+{
+	switch (action & ~CPU_TASKS_FROZEN) {
+	case CPU_DOWN_PREPARE:
+		cpuset_update_active_cpus();
+		return NOTIFY_OK;
+	default:
+		return NOTIFY_DONE;
+	}
+}
+
+void __init sched_init_smp(void)
+{
+	cpumask_var_t non_isolated_cpus;
+
+	alloc_cpumask_var(&non_isolated_cpus, GFP_KERNEL);
+	alloc_cpumask_var(&fallback_doms, GFP_KERNEL);
+
+	get_online_cpus();
+	mutex_lock(&sched_domains_mutex);
+	init_sched_domains(cpu_active_mask);
+	cpumask_andnot(non_isolated_cpus, cpu_possible_mask, cpu_isolated_map);
+	if (cpumask_empty(non_isolated_cpus))
+		cpumask_set_cpu(smp_processor_id(), non_isolated_cpus);
+	mutex_unlock(&sched_domains_mutex);
+	put_online_cpus();
+
+	hotcpu_notifier(cpuset_cpu_active, CPU_PRI_CPUSET_ACTIVE);
+	hotcpu_notifier(cpuset_cpu_inactive, CPU_PRI_CPUSET_INACTIVE);
+
+	/* RT runtime code needs to handle some hotplug events */
+	hotcpu_notifier(update_runtime, 0);
+
+	init_hrtick();
+
+	/* Move init over to a non-isolated CPU */
+	if (set_cpus_allowed_ptr(current, non_isolated_cpus) < 0)
+		BUG();
+	sched_init_granularity();
+	free_cpumask_var(non_isolated_cpus);
+
+	init_sched_rt_class();
+}
+#else
+void __init sched_init_smp(void)
+{
+	sched_init_granularity();
+}
+#endif /* CONFIG_SMP */
+
+const_debug unsigned int sysctl_timer_migration = 1;
+
+int in_sched_functions(unsigned long addr)
+{
+	return in_lock_functions(addr) ||
+		(addr >= (unsigned long)__sched_text_start
+		&& addr < (unsigned long)__sched_text_end);
+}
+
+#ifdef CONFIG_CGROUP_SCHED
+struct task_group root_task_group;
+#endif
+
+DECLARE_PER_CPU(cpumask_var_t, load_balance_tmpmask);
+
+void __init sched_init(void)
+{
+	int i, j;
+	unsigned long alloc_size = 0, ptr;
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+	alloc_size += 2 * nr_cpu_ids * sizeof(void **);
+#endif
+#ifdef CONFIG_RT_GROUP_SCHED
+	alloc_size += 2 * nr_cpu_ids * sizeof(void **);
+#endif
+#ifdef CONFIG_CPUMASK_OFFSTACK
+	alloc_size += num_possible_cpus() * cpumask_size();
+#endif
+	if (alloc_size) {
+		ptr = (unsigned long)kzalloc(alloc_size, GFP_NOWAIT);
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+		root_task_group.se = (struct sched_entity **)ptr;
+		ptr += nr_cpu_ids * sizeof(void **);
+
+		root_task_group.cfs_rq = (struct cfs_rq **)ptr;
+		ptr += nr_cpu_ids * sizeof(void **);
+
+#endif /* CONFIG_FAIR_GROUP_SCHED */
+#ifdef CONFIG_RT_GROUP_SCHED
+		root_task_group.rt_se = (struct sched_rt_entity **)ptr;
+		ptr += nr_cpu_ids * sizeof(void **);
+
+		root_task_group.rt_rq = (struct rt_rq **)ptr;
+		ptr += nr_cpu_ids * sizeof(void **);
+
+#endif /* CONFIG_RT_GROUP_SCHED */
+#ifdef CONFIG_CPUMASK_OFFSTACK
+		for_each_possible_cpu(i) {
+			per_cpu(load_balance_tmpmask, i) = (void *)ptr;
+			ptr += cpumask_size();
+		}
+#endif /* CONFIG_CPUMASK_OFFSTACK */
+	}
+
+#ifdef CONFIG_SMP
+	init_defrootdomain();
+#endif
+
+	init_rt_bandwidth(&def_rt_bandwidth,
+			global_rt_period(), global_rt_runtime());
+
+#ifdef CONFIG_RT_GROUP_SCHED
+	init_rt_bandwidth(&root_task_group.rt_bandwidth,
+			global_rt_period(), global_rt_runtime());
+#endif /* CONFIG_RT_GROUP_SCHED */
+
+#ifdef CONFIG_CGROUP_SCHED
+	list_add(&root_task_group.list, &task_groups);
+	INIT_LIST_HEAD(&root_task_group.children);
+	INIT_LIST_HEAD(&root_task_group.siblings);
+	autogroup_init(&init_task);
+
+#endif /* CONFIG_CGROUP_SCHED */
+
+#ifdef CONFIG_CGROUP_CPUACCT
+	root_cpuacct.cpustat = &kernel_cpustat;
+	root_cpuacct.cpuusage = alloc_percpu(u64);
+	/* Too early, not expected to fail */
+	BUG_ON(!root_cpuacct.cpuusage);
+#endif
+	for_each_possible_cpu(i) {
+		struct rq *rq;
+
+		rq = cpu_rq(i);
+		raw_spin_lock_init(&rq->lock);
+		rq->nr_running = 0;
+		rq->calc_load_active = 0;
+		rq->calc_load_update = jiffies + LOAD_FREQ;
+		init_cfs_rq(&rq->cfs);
+		init_rt_rq(&rq->rt, rq);
+#ifdef CONFIG_FAIR_GROUP_SCHED
+		root_task_group.shares = ROOT_TASK_GROUP_LOAD;
+		INIT_LIST_HEAD(&rq->leaf_cfs_rq_list);
+		/*
+		 * How much cpu bandwidth does root_task_group get?
+		 *
+		 * In case of task-groups formed thr' the cgroup filesystem, it
+		 * gets 100% of the cpu resources in the system. This overall
+		 * system cpu resource is divided among the tasks of
+		 * root_task_group and its child task-groups in a fair manner,
+		 * based on each entity's (task or task-group's) weight
+		 * (se->load.weight).
+		 *
+		 * In other words, if root_task_group has 10 tasks of weight
+		 * 1024) and two child groups A0 and A1 (of weight 1024 each),
+		 * then A0's share of the cpu resource is:
+		 *
+		 *	A0's bandwidth = 1024 / (10*1024 + 1024 + 1024) = 8.33%
+		 *
+		 * We achieve this by letting root_task_group's tasks sit
+		 * directly in rq->cfs (i.e root_task_group->se[] = NULL).
+		 */
+		init_cfs_bandwidth(&root_task_group.cfs_bandwidth);
+		init_tg_cfs_entry(&root_task_group, &rq->cfs, NULL, i, NULL);
+#endif /* CONFIG_FAIR_GROUP_SCHED */
+
+		rq->rt.rt_runtime = def_rt_bandwidth.rt_runtime;
+#ifdef CONFIG_RT_GROUP_SCHED
+		INIT_LIST_HEAD(&rq->leaf_rt_rq_list);
+		init_tg_rt_entry(&root_task_group, &rq->rt, NULL, i, NULL);
+#endif
+
+		for (j = 0; j < CPU_LOAD_IDX_MAX; j++)
+			rq->cpu_load[j] = 0;
+
+		rq->last_load_update_tick = jiffies;
+
+#ifdef CONFIG_SMP
+		rq->sd = NULL;
+		rq->rd = NULL;
+		rq->cpu_power = SCHED_POWER_SCALE;
+		rq->post_schedule = 0;
+		rq->active_balance = 0;
+		rq->next_balance = jiffies;
+		rq->push_cpu = 0;
+		rq->cpu = i;
+		rq->online = 0;
+		rq->idle_stamp = 0;
+		rq->avg_idle = 2*sysctl_sched_migration_cost;
+		rq_attach_root(rq, &def_root_domain);
+#ifdef CONFIG_NO_HZ
+		rq->nohz_flags = 0;
+#endif
+#endif
+		init_rq_hrtick(rq);
+		atomic_set(&rq->nr_iowait, 0);
+	}
+
+	set_load_weight(&init_task);
+
+#ifdef CONFIG_PREEMPT_NOTIFIERS
+	INIT_HLIST_HEAD(&init_task.preempt_notifiers);
+#endif
+
+#ifdef CONFIG_RT_MUTEXES
+	plist_head_init(&init_task.pi_waiters);
+#endif
+
+	/*
+	 * The boot idle thread does lazy MMU switching as well:
+	 */
+	atomic_inc(&init_mm.mm_count);
+	enter_lazy_tlb(&init_mm, current);
+
+	/*
+	 * Make us the idle thread. Technically, schedule() should not be
+	 * called from this thread, however somewhere below it might be,
+	 * but because we are the idle thread, we just pick up running again
+	 * when this runqueue becomes "idle".
+	 */
+	init_idle(current, smp_processor_id());
+
+	calc_load_update = jiffies + LOAD_FREQ;
+
+	/*
+	 * During early bootup we pretend to be a normal task:
+	 */
+	current->sched_class = &fair_sched_class;
+
+#ifdef CONFIG_SMP
+	zalloc_cpumask_var(&sched_domains_tmpmask, GFP_NOWAIT);
+	/* May be allocated at isolcpus cmdline parse time */
+	if (cpu_isolated_map == NULL)
+		zalloc_cpumask_var(&cpu_isolated_map, GFP_NOWAIT);
+#endif
+	init_sched_fair_class();
+
+	scheduler_running = 1;
+}
+
+#ifdef CONFIG_DEBUG_ATOMIC_SLEEP
+static inline int preempt_count_equals(int preempt_offset)
+{
+	int nested = (preempt_count() & ~PREEMPT_ACTIVE) + rcu_preempt_depth();
+
+	return (nested == preempt_offset);
+}
+
+void __might_sleep(const char *file, int line, int preempt_offset)
+{
+	static unsigned long prev_jiffy;	/* ratelimiting */
+
+	rcu_sleep_check(); /* WARN_ON_ONCE() by default, no rate limit reqd. */
+	if ((preempt_count_equals(preempt_offset) && !irqs_disabled()) ||
+	    system_state != SYSTEM_RUNNING || oops_in_progress)
+		return;
+	if (time_before(jiffies, prev_jiffy + HZ) && prev_jiffy)
+		return;
+	prev_jiffy = jiffies;
+
+	printk(KERN_ERR
+		"BUG: sleeping function called from invalid context at %s:%d\n",
+			file, line);
+	printk(KERN_ERR
+		"in_atomic(): %d, irqs_disabled(): %d, pid: %d, name: %s\n",
+			in_atomic(), irqs_disabled(),
+			current->pid, current->comm);
+
+	debug_show_held_locks(current);
+	if (irqs_disabled())
+		print_irqtrace_events(current);
+	dump_stack();
+}
+EXPORT_SYMBOL(__might_sleep);
+#endif
+
+#ifdef CONFIG_MAGIC_SYSRQ
+static void normalize_task(struct rq *rq, struct task_struct *p)
+{
+	const struct sched_class *prev_class = p->sched_class;
+	int old_prio = p->prio;
+	int on_rq;
+
+	on_rq = p->on_rq;
+	if (on_rq)
+		deactivate_task(rq, p, 0);
+	__setscheduler(rq, p, SCHED_NORMAL, 0);
+	if (on_rq) {
+		activate_task(rq, p, 0);
+		resched_task(rq->curr);
+	}
+
+	check_class_changed(rq, p, prev_class, old_prio);
+}
+
+void normalize_rt_tasks(void)
+{
+	struct task_struct *g, *p;
+	unsigned long flags;
+	struct rq *rq;
+
+	read_lock_irqsave(&tasklist_lock, flags);
+	do_each_thread(g, p) {
+		/*
+		 * Only normalize user tasks:
+		 */
+		if (!p->mm)
+			continue;
+
+		p->se.exec_start		= 0;
+#ifdef CONFIG_SCHEDSTATS
+		p->se.statistics.wait_start	= 0;
+		p->se.statistics.sleep_start	= 0;
+		p->se.statistics.block_start	= 0;
+#endif
+
+		if (!rt_task(p)) {
+			/*
+			 * Renice negative nice level userspace
+			 * tasks back to 0:
+			 */
+			if (TASK_NICE(p) < 0 && p->mm)
+				set_user_nice(p, 0);
+			continue;
+		}
+
+		raw_spin_lock(&p->pi_lock);
+		rq = __task_rq_lock(p);
+
+		normalize_task(rq, p);
+
+		__task_rq_unlock(rq);
+		raw_spin_unlock(&p->pi_lock);
+	} while_each_thread(g, p);
+
+	read_unlock_irqrestore(&tasklist_lock, flags);
+}
+
+#endif /* CONFIG_MAGIC_SYSRQ */
+
+#if defined(CONFIG_IA64) || defined(CONFIG_KGDB_KDB)
+/*
+ * These functions are only useful for the IA64 MCA handling, or kdb.
+ *
+ * They can only be called when the whole system has been
+ * stopped - every CPU needs to be quiescent, and no scheduling
+ * activity can take place. Using them for anything else would
+ * be a serious bug, and as a result, they aren't even visible
+ * under any other configuration.
+ */
+
+/**
+ * curr_task - return the current task for a given cpu.
+ * @cpu: the processor in question.
+ *
+ * ONLY VALID WHEN THE WHOLE SYSTEM IS STOPPED!
+ */
+struct task_struct *curr_task(int cpu)
+{
+	return cpu_curr(cpu);
+}
+
+#endif /* defined(CONFIG_IA64) || defined(CONFIG_KGDB_KDB) */
+
+#ifdef CONFIG_IA64
+/**
+ * set_curr_task - set the current task for a given cpu.
+ * @cpu: the processor in question.
+ * @p: the task pointer to set.
+ *
+ * Description: This function must only be used when non-maskable interrupts
+ * are serviced on a separate stack. It allows the architecture to switch the
+ * notion of the current task on a cpu in a non-blocking manner. This function
+ * must be called with all CPU's synchronized, and interrupts disabled, the
+ * and caller must save the original value of the current task (see
+ * curr_task() above) and restore that value before reenabling interrupts and
+ * re-starting the system.
+ *
+ * ONLY VALID WHEN THE WHOLE SYSTEM IS STOPPED!
+ */
+void set_curr_task(int cpu, struct task_struct *p)
+{
+	cpu_curr(cpu) = p;
+}
+
+#endif
+
+#ifdef CONFIG_CGROUP_SCHED
+/* task_group_lock serializes the addition/removal of task groups */
+static DEFINE_SPINLOCK(task_group_lock);
+
+static void free_sched_group(struct task_group *tg)
+{
+	free_fair_sched_group(tg);
+	free_rt_sched_group(tg);
+	autogroup_free(tg);
+	kfree(tg);
+}
+
+/* allocate runqueue etc for a new task group */
+struct task_group *sched_create_group(struct task_group *parent)
+{
+	struct task_group *tg;
+	unsigned long flags;
+
+	tg = kzalloc(sizeof(*tg), GFP_KERNEL);
+	if (!tg)
+		return ERR_PTR(-ENOMEM);
+
+	if (!alloc_fair_sched_group(tg, parent))
+		goto err;
+
+	if (!alloc_rt_sched_group(tg, parent))
+		goto err;
+
+	spin_lock_irqsave(&task_group_lock, flags);
+	list_add_rcu(&tg->list, &task_groups);
+
+	WARN_ON(!parent); /* root should already exist */
+
+	tg->parent = parent;
+	INIT_LIST_HEAD(&tg->children);
+	list_add_rcu(&tg->siblings, &parent->children);
+	spin_unlock_irqrestore(&task_group_lock, flags);
+
+	return tg;
+
+err:
+	free_sched_group(tg);
+	return ERR_PTR(-ENOMEM);
+}
+
+/* rcu callback to free various structures associated with a task group */
+static void free_sched_group_rcu(struct rcu_head *rhp)
+{
+	/* now it should be safe to free those cfs_rqs */
+	free_sched_group(container_of(rhp, struct task_group, rcu));
+}
+
+/* Destroy runqueue etc associated with a task group */
+void sched_destroy_group(struct task_group *tg)
+{
+	unsigned long flags;
+	int i;
+
+	/* end participation in shares distribution */
+	for_each_possible_cpu(i)
+		unregister_fair_sched_group(tg, i);
+
+	spin_lock_irqsave(&task_group_lock, flags);
+	list_del_rcu(&tg->list);
+	list_del_rcu(&tg->siblings);
+	spin_unlock_irqrestore(&task_group_lock, flags);
+
+	/* wait for possible concurrent references to cfs_rqs complete */
+	call_rcu(&tg->rcu, free_sched_group_rcu);
+}
+
+/* change task's runqueue when it moves between groups.
+ *	The caller of this function should have put the task in its new group
+ *	by now. This function just updates tsk->se.cfs_rq and tsk->se.parent to
+ *	reflect its new group.
+ */
+void sched_move_task(struct task_struct *tsk)
+{
+	int on_rq, running;
+	unsigned long flags;
+	struct rq *rq;
+
+	rq = task_rq_lock(tsk, &flags);
+
+	running = task_current(rq, tsk);
+	on_rq = tsk->on_rq;
+
+	if (on_rq)
+		dequeue_task(rq, tsk, 0);
+	if (unlikely(running))
+		tsk->sched_class->put_prev_task(rq, tsk);
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+	if (tsk->sched_class->task_move_group)
+		tsk->sched_class->task_move_group(tsk, on_rq);
+	else
+#endif
+		set_task_rq(tsk, task_cpu(tsk));
+
+	if (unlikely(running))
+		tsk->sched_class->set_curr_task(rq);
+	if (on_rq)
+		enqueue_task(rq, tsk, 0);
+
+	task_rq_unlock(rq, tsk, &flags);
+}
+#endif /* CONFIG_CGROUP_SCHED */
+
+#if defined(CONFIG_RT_GROUP_SCHED) || defined(CONFIG_CFS_BANDWIDTH)
+static unsigned long to_ratio(u64 period, u64 runtime)
+{
+	if (runtime == RUNTIME_INF)
+		return 1ULL << 20;
+
+	return div64_u64(runtime << 20, period);
+}
+#endif
+
+#ifdef CONFIG_RT_GROUP_SCHED
+/*
+ * Ensure that the real time constraints are schedulable.
+ */
+static DEFINE_MUTEX(rt_constraints_mutex);
+
+/* Must be called with tasklist_lock held */
+static inline int tg_has_rt_tasks(struct task_group *tg)
+{
+	struct task_struct *g, *p;
+
+	do_each_thread(g, p) {
+		if (rt_task(p) && task_rq(p)->rt.tg == tg)
+			return 1;
+	} while_each_thread(g, p);
+
+	return 0;
+}
+
+struct rt_schedulable_data {
+	struct task_group *tg;
+	u64 rt_period;
+	u64 rt_runtime;
+};
+
+static int tg_rt_schedulable(struct task_group *tg, void *data)
+{
+	struct rt_schedulable_data *d = data;
+	struct task_group *child;
+	unsigned long total, sum = 0;
+	u64 period, runtime;
+
+	period = ktime_to_ns(tg->rt_bandwidth.rt_period);
+	runtime = tg->rt_bandwidth.rt_runtime;
+
+	if (tg == d->tg) {
+		period = d->rt_period;
+		runtime = d->rt_runtime;
+	}
+
+	/*
+	 * Cannot have more runtime than the period.
+	 */
+	if (runtime > period && runtime != RUNTIME_INF)
+		return -EINVAL;
+
+	/*
+	 * Ensure we don't starve existing RT tasks.
+	 */
+	if (rt_bandwidth_enabled() && !runtime && tg_has_rt_tasks(tg))
+		return -EBUSY;
+
+	total = to_ratio(period, runtime);
+
+	/*
+	 * Nobody can have more than the global setting allows.
+	 */
+	if (total > to_ratio(global_rt_period(), global_rt_runtime()))
+		return -EINVAL;
+
+	/*
+	 * The sum of our children's runtime should not exceed our own.
+	 */
+	list_for_each_entry_rcu(child, &tg->children, siblings) {
+		period = ktime_to_ns(child->rt_bandwidth.rt_period);
+		runtime = child->rt_bandwidth.rt_runtime;
+
+		if (child == d->tg) {
+			period = d->rt_period;
+			runtime = d->rt_runtime;
+		}
+
+		sum += to_ratio(period, runtime);
+	}
+
+	if (sum > total)
+		return -EINVAL;
+
+	return 0;
+}
+
+static int __rt_schedulable(struct task_group *tg, u64 period, u64 runtime)
+{
+	int ret;
+
+	struct rt_schedulable_data data = {
+		.tg = tg,
+		.rt_period = period,
+		.rt_runtime = runtime,
+	};
+
+	rcu_read_lock();
+	ret = walk_tg_tree(tg_rt_schedulable, tg_nop, &data);
+	rcu_read_unlock();
+
+	return ret;
+}
+
+static int tg_set_rt_bandwidth(struct task_group *tg,
+		u64 rt_period, u64 rt_runtime)
+{
+	int i, err = 0;
+
+	mutex_lock(&rt_constraints_mutex);
+	read_lock(&tasklist_lock);
+	err = __rt_schedulable(tg, rt_period, rt_runtime);
+	if (err)
+		goto unlock;
+
+	raw_spin_lock_irq(&tg->rt_bandwidth.rt_runtime_lock);
+	tg->rt_bandwidth.rt_period = ns_to_ktime(rt_period);
+	tg->rt_bandwidth.rt_runtime = rt_runtime;
+
+	for_each_possible_cpu(i) {
+		struct rt_rq *rt_rq = tg->rt_rq[i];
+
+		raw_spin_lock(&rt_rq->rt_runtime_lock);
+		rt_rq->rt_runtime = rt_runtime;
+		raw_spin_unlock(&rt_rq->rt_runtime_lock);
+	}
+	raw_spin_unlock_irq(&tg->rt_bandwidth.rt_runtime_lock);
+unlock:
+	read_unlock(&tasklist_lock);
+	mutex_unlock(&rt_constraints_mutex);
+
+	return err;
+}
+
+int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us)
+{
+	u64 rt_runtime, rt_period;
+
+	rt_period = ktime_to_ns(tg->rt_bandwidth.rt_period);
+	rt_runtime = (u64)rt_runtime_us * NSEC_PER_USEC;
+	if (rt_runtime_us < 0)
+		rt_runtime = RUNTIME_INF;
+
+	return tg_set_rt_bandwidth(tg, rt_period, rt_runtime);
+}
+
+long sched_group_rt_runtime(struct task_group *tg)
+{
+	u64 rt_runtime_us;
+
+	if (tg->rt_bandwidth.rt_runtime == RUNTIME_INF)
+		return -1;
+
+	rt_runtime_us = tg->rt_bandwidth.rt_runtime;
+	do_div(rt_runtime_us, NSEC_PER_USEC);
+	return rt_runtime_us;
+}
+
+int sched_group_set_rt_period(struct task_group *tg, long rt_period_us)
+{
+	u64 rt_runtime, rt_period;
+
+	rt_period = (u64)rt_period_us * NSEC_PER_USEC;
+	rt_runtime = tg->rt_bandwidth.rt_runtime;
+
+	if (rt_period == 0)
+		return -EINVAL;
+
+	return tg_set_rt_bandwidth(tg, rt_period, rt_runtime);
+}
+
+long sched_group_rt_period(struct task_group *tg)
+{
+	u64 rt_period_us;
+
+	rt_period_us = ktime_to_ns(tg->rt_bandwidth.rt_period);
+	do_div(rt_period_us, NSEC_PER_USEC);
+	return rt_period_us;
+}
+
+static int sched_rt_global_constraints(void)
+{
+	u64 runtime, period;
+	int ret = 0;
+
+	if (sysctl_sched_rt_period <= 0)
+		return -EINVAL;
+
+	runtime = global_rt_runtime();
+	period = global_rt_period();
+
+	/*
+	 * Sanity check on the sysctl variables.
+	 */
+	if (runtime > period && runtime != RUNTIME_INF)
+		return -EINVAL;
+
+	mutex_lock(&rt_constraints_mutex);
+	read_lock(&tasklist_lock);
+	ret = __rt_schedulable(NULL, 0, 0);
+	read_unlock(&tasklist_lock);
+	mutex_unlock(&rt_constraints_mutex);
+
+	return ret;
+}
+
+int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk)
+{
+	/* Don't accept realtime tasks when there is no way for them to run */
+	if (rt_task(tsk) && tg->rt_bandwidth.rt_runtime == 0)
+		return 0;
+
+	return 1;
+}
+
+#else /* !CONFIG_RT_GROUP_SCHED */
+static int sched_rt_global_constraints(void)
+{
+	unsigned long flags;
+	int i;
+
+	if (sysctl_sched_rt_period <= 0)
+		return -EINVAL;
+
+	/*
+	 * There's always some RT tasks in the root group
+	 * -- migration, kstopmachine etc..
+	 */
+	if (sysctl_sched_rt_runtime == 0)
+		return -EBUSY;
+
+	raw_spin_lock_irqsave(&def_rt_bandwidth.rt_runtime_lock, flags);
+	for_each_possible_cpu(i) {
+		struct rt_rq *rt_rq = &cpu_rq(i)->rt;
+
+		raw_spin_lock(&rt_rq->rt_runtime_lock);
+		rt_rq->rt_runtime = global_rt_runtime();
+		raw_spin_unlock(&rt_rq->rt_runtime_lock);
+	}
+	raw_spin_unlock_irqrestore(&def_rt_bandwidth.rt_runtime_lock, flags);
+
+	return 0;
+}
+#endif /* CONFIG_RT_GROUP_SCHED */
+
+int sched_rt_handler(struct ctl_table *table, int write,
+		void __user *buffer, size_t *lenp,
+		loff_t *ppos)
+{
+	int ret;
+	int old_period, old_runtime;
+	static DEFINE_MUTEX(mutex);
+
+	mutex_lock(&mutex);
+	old_period = sysctl_sched_rt_period;
+	old_runtime = sysctl_sched_rt_runtime;
+
+	ret = proc_dointvec(table, write, buffer, lenp, ppos);
+
+	if (!ret && write) {
+		ret = sched_rt_global_constraints();
+		if (ret) {
+			sysctl_sched_rt_period = old_period;
+			sysctl_sched_rt_runtime = old_runtime;
+		} else {
+			def_rt_bandwidth.rt_runtime = global_rt_runtime();
+			def_rt_bandwidth.rt_period =
+				ns_to_ktime(global_rt_period());
+		}
+	}
+	mutex_unlock(&mutex);
+
+	return ret;
+}
+
+#ifdef CONFIG_CGROUP_SCHED
+
+/* return corresponding task_group object of a cgroup */
+static inline struct task_group *cgroup_tg(struct cgroup *cgrp)
+{
+	return container_of(cgroup_subsys_state(cgrp, cpu_cgroup_subsys_id),
+			    struct task_group, css);
+}
+
+static struct cgroup_subsys_state *
+cpu_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cgrp)
+{
+	struct task_group *tg, *parent;
+
+	if (!cgrp->parent) {
+		/* This is early initialization for the top cgroup */
+		return &root_task_group.css;
+	}
+
+	parent = cgroup_tg(cgrp->parent);
+	tg = sched_create_group(parent);
+	if (IS_ERR(tg))
+		return ERR_PTR(-ENOMEM);
+
+	return &tg->css;
+}
+
+static void
+cpu_cgroup_destroy(struct cgroup_subsys *ss, struct cgroup *cgrp)
+{
+	struct task_group *tg = cgroup_tg(cgrp);
+
+	sched_destroy_group(tg);
+}
+
+static int cpu_cgroup_can_attach(struct cgroup_subsys *ss, struct cgroup *cgrp,
+				 struct cgroup_taskset *tset)
+{
+	struct task_struct *task;
+
+	cgroup_taskset_for_each(task, cgrp, tset) {
+#ifdef CONFIG_RT_GROUP_SCHED
+		if (!sched_rt_can_attach(cgroup_tg(cgrp), task))
+			return -EINVAL;
+#else
+		/* We don't support RT-tasks being in separate groups */
+		if (task->sched_class != &fair_sched_class)
+			return -EINVAL;
+#endif
+	}
+	return 0;
+}
+
+static void cpu_cgroup_attach(struct cgroup_subsys *ss, struct cgroup *cgrp,
+			      struct cgroup_taskset *tset)
+{
+	struct task_struct *task;
+
+	cgroup_taskset_for_each(task, cgrp, tset)
+		sched_move_task(task);
+}
+
+static void
+cpu_cgroup_exit(struct cgroup_subsys *ss, struct cgroup *cgrp,
+		struct cgroup *old_cgrp, struct task_struct *task)
+{
+	/*
+	 * cgroup_exit() is called in the copy_process() failure path.
+	 * Ignore this case since the task hasn't ran yet, this avoids
+	 * trying to poke a half freed task state from generic code.
+	 */
+	if (!(task->flags & PF_EXITING))
+		return;
+
+	sched_move_task(task);
+}
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+static int cpu_shares_write_u64(struct cgroup *cgrp, struct cftype *cftype,
+				u64 shareval)
+{
+	return sched_group_set_shares(cgroup_tg(cgrp), scale_load(shareval));
+}
+
+static u64 cpu_shares_read_u64(struct cgroup *cgrp, struct cftype *cft)
+{
+	struct task_group *tg = cgroup_tg(cgrp);
+
+	return (u64) scale_load_down(tg->shares);
+}
+
+#ifdef CONFIG_CFS_BANDWIDTH
+static DEFINE_MUTEX(cfs_constraints_mutex);
+
+const u64 max_cfs_quota_period = 1 * NSEC_PER_SEC; /* 1s */
+const u64 min_cfs_quota_period = 1 * NSEC_PER_MSEC; /* 1ms */
+
+static int __cfs_schedulable(struct task_group *tg, u64 period, u64 runtime);
+
+static int tg_set_cfs_bandwidth(struct task_group *tg, u64 period, u64 quota)
+{
+	int i, ret = 0, runtime_enabled, runtime_was_enabled;
+	struct cfs_bandwidth *cfs_b = &tg->cfs_bandwidth;
+
+	if (tg == &root_task_group)
+		return -EINVAL;
+
+	/*
+	 * Ensure we have at some amount of bandwidth every period.  This is
+	 * to prevent reaching a state of large arrears when throttled via
+	 * entity_tick() resulting in prolonged exit starvation.
+	 */
+	if (quota < min_cfs_quota_period || period < min_cfs_quota_period)
+		return -EINVAL;
+
+	/*
+	 * Likewise, bound things on the otherside by preventing insane quota
+	 * periods.  This also allows us to normalize in computing quota
+	 * feasibility.
+	 */
+	if (period > max_cfs_quota_period)
+		return -EINVAL;
+
+	mutex_lock(&cfs_constraints_mutex);
+	ret = __cfs_schedulable(tg, period, quota);
+	if (ret)
+		goto out_unlock;
+
+	runtime_enabled = quota != RUNTIME_INF;
+	runtime_was_enabled = cfs_b->quota != RUNTIME_INF;
+	account_cfs_bandwidth_used(runtime_enabled, runtime_was_enabled);
+	raw_spin_lock_irq(&cfs_b->lock);
+	cfs_b->period = ns_to_ktime(period);
+	cfs_b->quota = quota;
+
+	__refill_cfs_bandwidth_runtime(cfs_b);
+	/* restart the period timer (if active) to handle new period expiry */
+	if (runtime_enabled && cfs_b->timer_active) {
+		/* force a reprogram */
+		cfs_b->timer_active = 0;
+		__start_cfs_bandwidth(cfs_b);
+	}
+	raw_spin_unlock_irq(&cfs_b->lock);
+
+	for_each_possible_cpu(i) {
+		struct cfs_rq *cfs_rq = tg->cfs_rq[i];
+		struct rq *rq = cfs_rq->rq;
+
+		raw_spin_lock_irq(&rq->lock);
+		cfs_rq->runtime_enabled = runtime_enabled;
+		cfs_rq->runtime_remaining = 0;
+
+		if (cfs_rq->throttled)
+			unthrottle_cfs_rq(cfs_rq);
+		raw_spin_unlock_irq(&rq->lock);
+	}
+out_unlock:
+	mutex_unlock(&cfs_constraints_mutex);
+
+	return ret;
+}
+
+int tg_set_cfs_quota(struct task_group *tg, long cfs_quota_us)
+{
+	u64 quota, period;
+
+	period = ktime_to_ns(tg->cfs_bandwidth.period);
+	if (cfs_quota_us < 0)
+		quota = RUNTIME_INF;
+	else
+		quota = (u64)cfs_quota_us * NSEC_PER_USEC;
+
+	return tg_set_cfs_bandwidth(tg, period, quota);
+}
+
+long tg_get_cfs_quota(struct task_group *tg)
+{
+	u64 quota_us;
+
+	if (tg->cfs_bandwidth.quota == RUNTIME_INF)
+		return -1;
+
+	quota_us = tg->cfs_bandwidth.quota;
+	do_div(quota_us, NSEC_PER_USEC);
+
+	return quota_us;
+}
+
+int tg_set_cfs_period(struct task_group *tg, long cfs_period_us)
+{
+	u64 quota, period;
+
+	period = (u64)cfs_period_us * NSEC_PER_USEC;
+	quota = tg->cfs_bandwidth.quota;
+
+	return tg_set_cfs_bandwidth(tg, period, quota);
+}
+
+long tg_get_cfs_period(struct task_group *tg)
+{
+	u64 cfs_period_us;
+
+	cfs_period_us = ktime_to_ns(tg->cfs_bandwidth.period);
+	do_div(cfs_period_us, NSEC_PER_USEC);
+
+	return cfs_period_us;
+}
+
+static s64 cpu_cfs_quota_read_s64(struct cgroup *cgrp, struct cftype *cft)
+{
+	return tg_get_cfs_quota(cgroup_tg(cgrp));
+}
+
+static int cpu_cfs_quota_write_s64(struct cgroup *cgrp, struct cftype *cftype,
+				s64 cfs_quota_us)
+{
+	return tg_set_cfs_quota(cgroup_tg(cgrp), cfs_quota_us);
+}
+
+static u64 cpu_cfs_period_read_u64(struct cgroup *cgrp, struct cftype *cft)
+{
+	return tg_get_cfs_period(cgroup_tg(cgrp));
+}
+
+static int cpu_cfs_period_write_u64(struct cgroup *cgrp, struct cftype *cftype,
+				u64 cfs_period_us)
+{
+	return tg_set_cfs_period(cgroup_tg(cgrp), cfs_period_us);
+}
+
+struct cfs_schedulable_data {
+	struct task_group *tg;
+	u64 period, quota;
+};
+
+/*
+ * normalize group quota/period to be quota/max_period
+ * note: units are usecs
+ */
+static u64 normalize_cfs_quota(struct task_group *tg,
+			       struct cfs_schedulable_data *d)
+{
+	u64 quota, period;
+
+	if (tg == d->tg) {
+		period = d->period;
+		quota = d->quota;
+	} else {
+		period = tg_get_cfs_period(tg);
+		quota = tg_get_cfs_quota(tg);
+	}
+
+	/* note: these should typically be equivalent */
+	if (quota == RUNTIME_INF || quota == -1)
+		return RUNTIME_INF;
+
+	return to_ratio(period, quota);
+}
+
+static int tg_cfs_schedulable_down(struct task_group *tg, void *data)
+{
+	struct cfs_schedulable_data *d = data;
+	struct cfs_bandwidth *cfs_b = &tg->cfs_bandwidth;
+	s64 quota = 0, parent_quota = -1;
+
+	if (!tg->parent) {
+		quota = RUNTIME_INF;
+	} else {
+		struct cfs_bandwidth *parent_b = &tg->parent->cfs_bandwidth;
+
+		quota = normalize_cfs_quota(tg, d);
+		parent_quota = parent_b->hierarchal_quota;
+
+		/*
+		 * ensure max(child_quota) <= parent_quota, inherit when no
+		 * limit is set
+		 */
+		if (quota == RUNTIME_INF)
+			quota = parent_quota;
+		else if (parent_quota != RUNTIME_INF && quota > parent_quota)
+			return -EINVAL;
+	}
+	cfs_b->hierarchal_quota = quota;
+
+	return 0;
+}
+
+static int __cfs_schedulable(struct task_group *tg, u64 period, u64 quota)
+{
+	int ret;
+	struct cfs_schedulable_data data = {
+		.tg = tg,
+		.period = period,
+		.quota = quota,
+	};
+
+	if (quota != RUNTIME_INF) {
+		do_div(data.period, NSEC_PER_USEC);
+		do_div(data.quota, NSEC_PER_USEC);
+	}
+
+	rcu_read_lock();
+	ret = walk_tg_tree(tg_cfs_schedulable_down, tg_nop, &data);
+	rcu_read_unlock();
+
+	return ret;
+}
+
+static int cpu_stats_show(struct cgroup *cgrp, struct cftype *cft,
+		struct cgroup_map_cb *cb)
+{
+	struct task_group *tg = cgroup_tg(cgrp);
+	struct cfs_bandwidth *cfs_b = &tg->cfs_bandwidth;
+
+	cb->fill(cb, "nr_periods", cfs_b->nr_periods);
+	cb->fill(cb, "nr_throttled", cfs_b->nr_throttled);
+	cb->fill(cb, "throttled_time", cfs_b->throttled_time);
+
+	return 0;
+}
+#endif /* CONFIG_CFS_BANDWIDTH */
+#endif /* CONFIG_FAIR_GROUP_SCHED */
+
+#ifdef CONFIG_RT_GROUP_SCHED
+static int cpu_rt_runtime_write(struct cgroup *cgrp, struct cftype *cft,
+				s64 val)
+{
+	return sched_group_set_rt_runtime(cgroup_tg(cgrp), val);
+}
+
+static s64 cpu_rt_runtime_read(struct cgroup *cgrp, struct cftype *cft)
+{
+	return sched_group_rt_runtime(cgroup_tg(cgrp));
+}
+
+static int cpu_rt_period_write_uint(struct cgroup *cgrp, struct cftype *cftype,
+		u64 rt_period_us)
+{
+	return sched_group_set_rt_period(cgroup_tg(cgrp), rt_period_us);
+}
+
+static u64 cpu_rt_period_read_uint(struct cgroup *cgrp, struct cftype *cft)
+{
+	return sched_group_rt_period(cgroup_tg(cgrp));
+}
+#endif /* CONFIG_RT_GROUP_SCHED */
+
+static struct cftype cpu_files[] = {
+#ifdef CONFIG_FAIR_GROUP_SCHED
+	{
+		.name = "shares",
+		.read_u64 = cpu_shares_read_u64,
+		.write_u64 = cpu_shares_write_u64,
+	},
+#endif
+#ifdef CONFIG_CFS_BANDWIDTH
+	{
+		.name = "cfs_quota_us",
+		.read_s64 = cpu_cfs_quota_read_s64,
+		.write_s64 = cpu_cfs_quota_write_s64,
+	},
+	{
+		.name = "cfs_period_us",
+		.read_u64 = cpu_cfs_period_read_u64,
+		.write_u64 = cpu_cfs_period_write_u64,
+	},
+	{
+		.name = "stat",
+		.read_map = cpu_stats_show,
+	},
+#endif
+#ifdef CONFIG_RT_GROUP_SCHED
+	{
+		.name = "rt_runtime_us",
+		.read_s64 = cpu_rt_runtime_read,
+		.write_s64 = cpu_rt_runtime_write,
+	},
+	{
+		.name = "rt_period_us",
+		.read_u64 = cpu_rt_period_read_uint,
+		.write_u64 = cpu_rt_period_write_uint,
+	},
+#endif
+};
+
+static int cpu_cgroup_populate(struct cgroup_subsys *ss, struct cgroup *cont)
+{
+	return cgroup_add_files(cont, ss, cpu_files, ARRAY_SIZE(cpu_files));
+}
+
+struct cgroup_subsys cpu_cgroup_subsys = {
+	.name		= "cpu",
+	.create		= cpu_cgroup_create,
+	.destroy	= cpu_cgroup_destroy,
+	.can_attach	= cpu_cgroup_can_attach,
+	.attach		= cpu_cgroup_attach,
+	.exit		= cpu_cgroup_exit,
+	.populate	= cpu_cgroup_populate,
+	.subsys_id	= cpu_cgroup_subsys_id,
+	.early_init	= 1,
+};
+
+#endif	/* CONFIG_CGROUP_SCHED */
+
+#ifdef CONFIG_CGROUP_CPUACCT
+
+/*
+ * CPU accounting code for task groups.
+ *
+ * Based on the work by Paul Menage (menage@google.com) and Balbir Singh
+ * (balbir@in.ibm.com).
+ */
+
+/* create a new cpu accounting group */
+static struct cgroup_subsys_state *cpuacct_create(
+	struct cgroup_subsys *ss, struct cgroup *cgrp)
+{
+	struct cpuacct *ca;
+
+	if (!cgrp->parent)
+		return &root_cpuacct.css;
+
+	ca = kzalloc(sizeof(*ca), GFP_KERNEL);
+	if (!ca)
+		goto out;
+
+	ca->cpuusage = alloc_percpu(u64);
+	if (!ca->cpuusage)
+		goto out_free_ca;
+
+	ca->cpustat = alloc_percpu(struct kernel_cpustat);
+	if (!ca->cpustat)
+		goto out_free_cpuusage;
+
+	return &ca->css;
+
+out_free_cpuusage:
+	free_percpu(ca->cpuusage);
+out_free_ca:
+	kfree(ca);
+out:
+	return ERR_PTR(-ENOMEM);
+}
+
+/* destroy an existing cpu accounting group */
+static void
+cpuacct_destroy(struct cgroup_subsys *ss, struct cgroup *cgrp)
+{
+	struct cpuacct *ca = cgroup_ca(cgrp);
+
+	free_percpu(ca->cpustat);
+	free_percpu(ca->cpuusage);
+	kfree(ca);
+}
+
+static u64 cpuacct_cpuusage_read(struct cpuacct *ca, int cpu)
+{
+	u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
+	u64 data;
+
+#ifndef CONFIG_64BIT
+	/*
+	 * Take rq->lock to make 64-bit read safe on 32-bit platforms.
+	 */
+	raw_spin_lock_irq(&cpu_rq(cpu)->lock);
+	data = *cpuusage;
+	raw_spin_unlock_irq(&cpu_rq(cpu)->lock);
+#else
+	data = *cpuusage;
+#endif
+
+	return data;
+}
+
+static void cpuacct_cpuusage_write(struct cpuacct *ca, int cpu, u64 val)
+{
+	u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
+
+#ifndef CONFIG_64BIT
+	/*
+	 * Take rq->lock to make 64-bit write safe on 32-bit platforms.
+	 */
+	raw_spin_lock_irq(&cpu_rq(cpu)->lock);
+	*cpuusage = val;
+	raw_spin_unlock_irq(&cpu_rq(cpu)->lock);
+#else
+	*cpuusage = val;
+#endif
+}
+
+/* return total cpu usage (in nanoseconds) of a group */
+static u64 cpuusage_read(struct cgroup *cgrp, struct cftype *cft)
+{
+	struct cpuacct *ca = cgroup_ca(cgrp);
+	u64 totalcpuusage = 0;
+	int i;
+
+	for_each_present_cpu(i)
+		totalcpuusage += cpuacct_cpuusage_read(ca, i);
+
+	return totalcpuusage;
+}
+
+static int cpuusage_write(struct cgroup *cgrp, struct cftype *cftype,
+								u64 reset)
+{
+	struct cpuacct *ca = cgroup_ca(cgrp);
+	int err = 0;
+	int i;
+
+	if (reset) {
+		err = -EINVAL;
+		goto out;
+	}
+
+	for_each_present_cpu(i)
+		cpuacct_cpuusage_write(ca, i, 0);
+
+out:
+	return err;
+}
+
+static int cpuacct_percpu_seq_read(struct cgroup *cgroup, struct cftype *cft,
+				   struct seq_file *m)
+{
+	struct cpuacct *ca = cgroup_ca(cgroup);
+	u64 percpu;
+	int i;
+
+	for_each_present_cpu(i) {
+		percpu = cpuacct_cpuusage_read(ca, i);
+		seq_printf(m, "%llu ", (unsigned long long) percpu);
+	}
+	seq_printf(m, "\n");
+	return 0;
+}
+
+static const char *cpuacct_stat_desc[] = {
+	[CPUACCT_STAT_USER] = "user",
+	[CPUACCT_STAT_SYSTEM] = "system",
+};
+
+static int cpuacct_stats_show(struct cgroup *cgrp, struct cftype *cft,
+			      struct cgroup_map_cb *cb)
+{
+	struct cpuacct *ca = cgroup_ca(cgrp);
+	int cpu;
+	s64 val = 0;
+
+	for_each_online_cpu(cpu) {
+		struct kernel_cpustat *kcpustat = per_cpu_ptr(ca->cpustat, cpu);
+		val += kcpustat->cpustat[CPUTIME_USER];
+		val += kcpustat->cpustat[CPUTIME_NICE];
+	}
+	val = cputime64_to_clock_t(val);
+	cb->fill(cb, cpuacct_stat_desc[CPUACCT_STAT_USER], val);
+
+	val = 0;
+	for_each_online_cpu(cpu) {
+		struct kernel_cpustat *kcpustat = per_cpu_ptr(ca->cpustat, cpu);
+		val += kcpustat->cpustat[CPUTIME_SYSTEM];
+		val += kcpustat->cpustat[CPUTIME_IRQ];
+		val += kcpustat->cpustat[CPUTIME_SOFTIRQ];
+	}
+
+	val = cputime64_to_clock_t(val);
+	cb->fill(cb, cpuacct_stat_desc[CPUACCT_STAT_SYSTEM], val);
+
+	return 0;
+}
+
+static struct cftype files[] = {
+	{
+		.name = "usage",
+		.read_u64 = cpuusage_read,
+		.write_u64 = cpuusage_write,
+	},
+	{
+		.name = "usage_percpu",
+		.read_seq_string = cpuacct_percpu_seq_read,
+	},
+	{
+		.name = "stat",
+		.read_map = cpuacct_stats_show,
+	},
+};
+
+static int cpuacct_populate(struct cgroup_subsys *ss, struct cgroup *cgrp)
+{
+	return cgroup_add_files(cgrp, ss, files, ARRAY_SIZE(files));
+}
+
+/*
+ * charge this task's execution time to its accounting group.
+ *
+ * called with rq->lock held.
+ */
+void cpuacct_charge(struct task_struct *tsk, u64 cputime)
+{
+	struct cpuacct *ca;
+	int cpu;
+
+	if (unlikely(!cpuacct_subsys.active))
+		return;
+
+	cpu = task_cpu(tsk);
+
+	rcu_read_lock();
+
+	ca = task_ca(tsk);
+
+	for (; ca; ca = parent_ca(ca)) {
+		u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu);
+		*cpuusage += cputime;
+	}
+
+	rcu_read_unlock();
+}
+
+struct cgroup_subsys cpuacct_subsys = {
+	.name = "cpuacct",
+	.create = cpuacct_create,
+	.destroy = cpuacct_destroy,
+	.populate = cpuacct_populate,
+	.subsys_id = cpuacct_subsys_id,
+};
+#endif	/* CONFIG_CGROUP_CPUACCT */
diff --git a/kernel/sched/cpupri.c b/kernel/sched/cpupri.c
new file mode 100644
index 00000000000..b0d798eaf13
--- /dev/null
+++ b/kernel/sched/cpupri.c
@@ -0,0 +1,241 @@
+/*
+ *  kernel/sched/cpupri.c
+ *
+ *  CPU priority management
+ *
+ *  Copyright (C) 2007-2008 Novell
+ *
+ *  Author: Gregory Haskins <ghaskins@novell.com>
+ *
+ *  This code tracks the priority of each CPU so that global migration
+ *  decisions are easy to calculate.  Each CPU can be in a state as follows:
+ *
+ *                 (INVALID), IDLE, NORMAL, RT1, ... RT99
+ *
+ *  going from the lowest priority to the highest.  CPUs in the INVALID state
+ *  are not eligible for routing.  The system maintains this state with
+ *  a 2 dimensional bitmap (the first for priority class, the second for cpus
+ *  in that class).  Therefore a typical application without affinity
+ *  restrictions can find a suitable CPU with O(1) complexity (e.g. two bit
+ *  searches).  For tasks with affinity restrictions, the algorithm has a
+ *  worst case complexity of O(min(102, nr_domcpus)), though the scenario that
+ *  yields the worst case search is fairly contrived.
+ *
+ *  This program is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU General Public License
+ *  as published by the Free Software Foundation; version 2
+ *  of the License.
+ */
+
+#include <linux/gfp.h>
+#include "cpupri.h"
+
+/* Convert between a 140 based task->prio, and our 102 based cpupri */
+static int convert_prio(int prio)
+{
+	int cpupri;
+
+	if (prio == CPUPRI_INVALID)
+		cpupri = CPUPRI_INVALID;
+	else if (prio == MAX_PRIO)
+		cpupri = CPUPRI_IDLE;
+	else if (prio >= MAX_RT_PRIO)
+		cpupri = CPUPRI_NORMAL;
+	else
+		cpupri = MAX_RT_PRIO - prio + 1;
+
+	return cpupri;
+}
+
+/**
+ * cpupri_find - find the best (lowest-pri) CPU in the system
+ * @cp: The cpupri context
+ * @p: The task
+ * @lowest_mask: A mask to fill in with selected CPUs (or NULL)
+ *
+ * Note: This function returns the recommended CPUs as calculated during the
+ * current invocation.  By the time the call returns, the CPUs may have in
+ * fact changed priorities any number of times.  While not ideal, it is not
+ * an issue of correctness since the normal rebalancer logic will correct
+ * any discrepancies created by racing against the uncertainty of the current
+ * priority configuration.
+ *
+ * Returns: (int)bool - CPUs were found
+ */
+int cpupri_find(struct cpupri *cp, struct task_struct *p,
+		struct cpumask *lowest_mask)
+{
+	int                  idx      = 0;
+	int                  task_pri = convert_prio(p->prio);
+
+	if (task_pri >= MAX_RT_PRIO)
+		return 0;
+
+	for (idx = 0; idx < task_pri; idx++) {
+		struct cpupri_vec *vec  = &cp->pri_to_cpu[idx];
+		int skip = 0;
+
+		if (!atomic_read(&(vec)->count))
+			skip = 1;
+		/*
+		 * When looking at the vector, we need to read the counter,
+		 * do a memory barrier, then read the mask.
+		 *
+		 * Note: This is still all racey, but we can deal with it.
+		 *  Ideally, we only want to look at masks that are set.
+		 *
+		 *  If a mask is not set, then the only thing wrong is that we
+		 *  did a little more work than necessary.
+		 *
+		 *  If we read a zero count but the mask is set, because of the
+		 *  memory barriers, that can only happen when the highest prio
+		 *  task for a run queue has left the run queue, in which case,
+		 *  it will be followed by a pull. If the task we are processing
+		 *  fails to find a proper place to go, that pull request will
+		 *  pull this task if the run queue is running at a lower
+		 *  priority.
+		 */
+		smp_rmb();
+
+		/* Need to do the rmb for every iteration */
+		if (skip)
+			continue;
+
+		if (cpumask_any_and(&p->cpus_allowed, vec->mask) >= nr_cpu_ids)
+			continue;
+
+		if (lowest_mask) {
+			cpumask_and(lowest_mask, &p->cpus_allowed, vec->mask);
+
+			/*
+			 * We have to ensure that we have at least one bit
+			 * still set in the array, since the map could have
+			 * been concurrently emptied between the first and
+			 * second reads of vec->mask.  If we hit this
+			 * condition, simply act as though we never hit this
+			 * priority level and continue on.
+			 */
+			if (cpumask_any(lowest_mask) >= nr_cpu_ids)
+				continue;
+		}
+
+		return 1;
+	}
+
+	return 0;
+}
+
+/**
+ * cpupri_set - update the cpu priority setting
+ * @cp: The cpupri context
+ * @cpu: The target cpu
+ * @pri: The priority (INVALID-RT99) to assign to this CPU
+ *
+ * Note: Assumes cpu_rq(cpu)->lock is locked
+ *
+ * Returns: (void)
+ */
+void cpupri_set(struct cpupri *cp, int cpu, int newpri)
+{
+	int                 *currpri = &cp->cpu_to_pri[cpu];
+	int                  oldpri  = *currpri;
+	int                  do_mb = 0;
+
+	newpri = convert_prio(newpri);
+
+	BUG_ON(newpri >= CPUPRI_NR_PRIORITIES);
+
+	if (newpri == oldpri)
+		return;
+
+	/*
+	 * If the cpu was currently mapped to a different value, we
+	 * need to map it to the new value then remove the old value.
+	 * Note, we must add the new value first, otherwise we risk the
+	 * cpu being missed by the priority loop in cpupri_find.
+	 */
+	if (likely(newpri != CPUPRI_INVALID)) {
+		struct cpupri_vec *vec = &cp->pri_to_cpu[newpri];
+
+		cpumask_set_cpu(cpu, vec->mask);
+		/*
+		 * When adding a new vector, we update the mask first,
+		 * do a write memory barrier, and then update the count, to
+		 * make sure the vector is visible when count is set.
+		 */
+		smp_mb__before_atomic_inc();
+		atomic_inc(&(vec)->count);
+		do_mb = 1;
+	}
+	if (likely(oldpri != CPUPRI_INVALID)) {
+		struct cpupri_vec *vec  = &cp->pri_to_cpu[oldpri];
+
+		/*
+		 * Because the order of modification of the vec->count
+		 * is important, we must make sure that the update
+		 * of the new prio is seen before we decrement the
+		 * old prio. This makes sure that the loop sees
+		 * one or the other when we raise the priority of
+		 * the run queue. We don't care about when we lower the
+		 * priority, as that will trigger an rt pull anyway.
+		 *
+		 * We only need to do a memory barrier if we updated
+		 * the new priority vec.
+		 */
+		if (do_mb)
+			smp_mb__after_atomic_inc();
+
+		/*
+		 * When removing from the vector, we decrement the counter first
+		 * do a memory barrier and then clear the mask.
+		 */
+		atomic_dec(&(vec)->count);
+		smp_mb__after_atomic_inc();
+		cpumask_clear_cpu(cpu, vec->mask);
+	}
+
+	*currpri = newpri;
+}
+
+/**
+ * cpupri_init - initialize the cpupri structure
+ * @cp: The cpupri context
+ * @bootmem: true if allocations need to use bootmem
+ *
+ * Returns: -ENOMEM if memory fails.
+ */
+int cpupri_init(struct cpupri *cp)
+{
+	int i;
+
+	memset(cp, 0, sizeof(*cp));
+
+	for (i = 0; i < CPUPRI_NR_PRIORITIES; i++) {
+		struct cpupri_vec *vec = &cp->pri_to_cpu[i];
+
+		atomic_set(&vec->count, 0);
+		if (!zalloc_cpumask_var(&vec->mask, GFP_KERNEL))
+			goto cleanup;
+	}
+
+	for_each_possible_cpu(i)
+		cp->cpu_to_pri[i] = CPUPRI_INVALID;
+	return 0;
+
+cleanup:
+	for (i--; i >= 0; i--)
+		free_cpumask_var(cp->pri_to_cpu[i].mask);
+	return -ENOMEM;
+}
+
+/**
+ * cpupri_cleanup - clean up the cpupri structure
+ * @cp: The cpupri context
+ */
+void cpupri_cleanup(struct cpupri *cp)
+{
+	int i;
+
+	for (i = 0; i < CPUPRI_NR_PRIORITIES; i++)
+		free_cpumask_var(cp->pri_to_cpu[i].mask);
+}
diff --git a/kernel/sched/cpupri.h b/kernel/sched/cpupri.h
new file mode 100644
index 00000000000..f6d75617349
--- /dev/null
+++ b/kernel/sched/cpupri.h
@@ -0,0 +1,34 @@
+#ifndef _LINUX_CPUPRI_H
+#define _LINUX_CPUPRI_H
+
+#include <linux/sched.h>
+
+#define CPUPRI_NR_PRIORITIES	(MAX_RT_PRIO + 2)
+
+#define CPUPRI_INVALID -1
+#define CPUPRI_IDLE     0
+#define CPUPRI_NORMAL   1
+/* values 2-101 are RT priorities 0-99 */
+
+struct cpupri_vec {
+	atomic_t	count;
+	cpumask_var_t	mask;
+};
+
+struct cpupri {
+	struct cpupri_vec pri_to_cpu[CPUPRI_NR_PRIORITIES];
+	int               cpu_to_pri[NR_CPUS];
+};
+
+#ifdef CONFIG_SMP
+int  cpupri_find(struct cpupri *cp,
+		 struct task_struct *p, struct cpumask *lowest_mask);
+void cpupri_set(struct cpupri *cp, int cpu, int pri);
+int cpupri_init(struct cpupri *cp);
+void cpupri_cleanup(struct cpupri *cp);
+#else
+#define cpupri_set(cp, cpu, pri) do { } while (0)
+#define cpupri_init() do { } while (0)
+#endif
+
+#endif /* _LINUX_CPUPRI_H */
diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c
new file mode 100644
index 00000000000..2a075e10004
--- /dev/null
+++ b/kernel/sched/debug.c
@@ -0,0 +1,510 @@
+/*
+ * kernel/sched/debug.c
+ *
+ * Print the CFS rbtree
+ *
+ * Copyright(C) 2007, Red Hat, Inc., Ingo Molnar
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/proc_fs.h>
+#include <linux/sched.h>
+#include <linux/seq_file.h>
+#include <linux/kallsyms.h>
+#include <linux/utsname.h>
+
+#include "sched.h"
+
+static DEFINE_SPINLOCK(sched_debug_lock);
+
+/*
+ * This allows printing both to /proc/sched_debug and
+ * to the console
+ */
+#define SEQ_printf(m, x...)			\
+ do {						\
+	if (m)					\
+		seq_printf(m, x);		\
+	else					\
+		printk(x);			\
+ } while (0)
+
+/*
+ * Ease the printing of nsec fields:
+ */
+static long long nsec_high(unsigned long long nsec)
+{
+	if ((long long)nsec < 0) {
+		nsec = -nsec;
+		do_div(nsec, 1000000);
+		return -nsec;
+	}
+	do_div(nsec, 1000000);
+
+	return nsec;
+}
+
+static unsigned long nsec_low(unsigned long long nsec)
+{
+	if ((long long)nsec < 0)
+		nsec = -nsec;
+
+	return do_div(nsec, 1000000);
+}
+
+#define SPLIT_NS(x) nsec_high(x), nsec_low(x)
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+static void print_cfs_group_stats(struct seq_file *m, int cpu, struct task_group *tg)
+{
+	struct sched_entity *se = tg->se[cpu];
+	if (!se)
+		return;
+
+#define P(F) \
+	SEQ_printf(m, "  .%-30s: %lld\n", #F, (long long)F)
+#define PN(F) \
+	SEQ_printf(m, "  .%-30s: %lld.%06ld\n", #F, SPLIT_NS((long long)F))
+
+	PN(se->exec_start);
+	PN(se->vruntime);
+	PN(se->sum_exec_runtime);
+#ifdef CONFIG_SCHEDSTATS
+	PN(se->statistics.wait_start);
+	PN(se->statistics.sleep_start);
+	PN(se->statistics.block_start);
+	PN(se->statistics.sleep_max);
+	PN(se->statistics.block_max);
+	PN(se->statistics.exec_max);
+	PN(se->statistics.slice_max);
+	PN(se->statistics.wait_max);
+	PN(se->statistics.wait_sum);
+	P(se->statistics.wait_count);
+#endif
+	P(se->load.weight);
+#undef PN
+#undef P
+}
+#endif
+
+#ifdef CONFIG_CGROUP_SCHED
+static char group_path[PATH_MAX];
+
+static char *task_group_path(struct task_group *tg)
+{
+	if (autogroup_path(tg, group_path, PATH_MAX))
+		return group_path;
+
+	/*
+	 * May be NULL if the underlying cgroup isn't fully-created yet
+	 */
+	if (!tg->css.cgroup) {
+		group_path[0] = '\0';
+		return group_path;
+	}
+	cgroup_path(tg->css.cgroup, group_path, PATH_MAX);
+	return group_path;
+}
+#endif
+
+static void
+print_task(struct seq_file *m, struct rq *rq, struct task_struct *p)
+{
+	if (rq->curr == p)
+		SEQ_printf(m, "R");
+	else
+		SEQ_printf(m, " ");
+
+	SEQ_printf(m, "%15s %5d %9Ld.%06ld %9Ld %5d ",
+		p->comm, p->pid,
+		SPLIT_NS(p->se.vruntime),
+		(long long)(p->nvcsw + p->nivcsw),
+		p->prio);
+#ifdef CONFIG_SCHEDSTATS
+	SEQ_printf(m, "%9Ld.%06ld %9Ld.%06ld %9Ld.%06ld",
+		SPLIT_NS(p->se.vruntime),
+		SPLIT_NS(p->se.sum_exec_runtime),
+		SPLIT_NS(p->se.statistics.sum_sleep_runtime));
+#else
+	SEQ_printf(m, "%15Ld %15Ld %15Ld.%06ld %15Ld.%06ld %15Ld.%06ld",
+		0LL, 0LL, 0LL, 0L, 0LL, 0L, 0LL, 0L);
+#endif
+#ifdef CONFIG_CGROUP_SCHED
+	SEQ_printf(m, " %s", task_group_path(task_group(p)));
+#endif
+
+	SEQ_printf(m, "\n");
+}
+
+static void print_rq(struct seq_file *m, struct rq *rq, int rq_cpu)
+{
+	struct task_struct *g, *p;
+	unsigned long flags;
+
+	SEQ_printf(m,
+	"\nrunnable tasks:\n"
+	"            task   PID         tree-key  switches  prio"
+	"     exec-runtime         sum-exec        sum-sleep\n"
+	"------------------------------------------------------"
+	"----------------------------------------------------\n");
+
+	read_lock_irqsave(&tasklist_lock, flags);
+
+	do_each_thread(g, p) {
+		if (!p->on_rq || task_cpu(p) != rq_cpu)
+			continue;
+
+		print_task(m, rq, p);
+	} while_each_thread(g, p);
+
+	read_unlock_irqrestore(&tasklist_lock, flags);
+}
+
+void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
+{
+	s64 MIN_vruntime = -1, min_vruntime, max_vruntime = -1,
+		spread, rq0_min_vruntime, spread0;
+	struct rq *rq = cpu_rq(cpu);
+	struct sched_entity *last;
+	unsigned long flags;
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+	SEQ_printf(m, "\ncfs_rq[%d]:%s\n", cpu, task_group_path(cfs_rq->tg));
+#else
+	SEQ_printf(m, "\ncfs_rq[%d]:\n", cpu);
+#endif
+	SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "exec_clock",
+			SPLIT_NS(cfs_rq->exec_clock));
+
+	raw_spin_lock_irqsave(&rq->lock, flags);
+	if (cfs_rq->rb_leftmost)
+		MIN_vruntime = (__pick_first_entity(cfs_rq))->vruntime;
+	last = __pick_last_entity(cfs_rq);
+	if (last)
+		max_vruntime = last->vruntime;
+	min_vruntime = cfs_rq->min_vruntime;
+	rq0_min_vruntime = cpu_rq(0)->cfs.min_vruntime;
+	raw_spin_unlock_irqrestore(&rq->lock, flags);
+	SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "MIN_vruntime",
+			SPLIT_NS(MIN_vruntime));
+	SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "min_vruntime",
+			SPLIT_NS(min_vruntime));
+	SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "max_vruntime",
+			SPLIT_NS(max_vruntime));
+	spread = max_vruntime - MIN_vruntime;
+	SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "spread",
+			SPLIT_NS(spread));
+	spread0 = min_vruntime - rq0_min_vruntime;
+	SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "spread0",
+			SPLIT_NS(spread0));
+	SEQ_printf(m, "  .%-30s: %d\n", "nr_spread_over",
+			cfs_rq->nr_spread_over);
+	SEQ_printf(m, "  .%-30s: %ld\n", "nr_running", cfs_rq->nr_running);
+	SEQ_printf(m, "  .%-30s: %ld\n", "load", cfs_rq->load.weight);
+#ifdef CONFIG_FAIR_GROUP_SCHED
+#ifdef CONFIG_SMP
+	SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "load_avg",
+			SPLIT_NS(cfs_rq->load_avg));
+	SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "load_period",
+			SPLIT_NS(cfs_rq->load_period));
+	SEQ_printf(m, "  .%-30s: %ld\n", "load_contrib",
+			cfs_rq->load_contribution);
+	SEQ_printf(m, "  .%-30s: %d\n", "load_tg",
+			atomic_read(&cfs_rq->tg->load_weight));
+#endif
+
+	print_cfs_group_stats(m, cpu, cfs_rq->tg);
+#endif
+}
+
+void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq)
+{
+#ifdef CONFIG_RT_GROUP_SCHED
+	SEQ_printf(m, "\nrt_rq[%d]:%s\n", cpu, task_group_path(rt_rq->tg));
+#else
+	SEQ_printf(m, "\nrt_rq[%d]:\n", cpu);
+#endif
+
+#define P(x) \
+	SEQ_printf(m, "  .%-30s: %Ld\n", #x, (long long)(rt_rq->x))
+#define PN(x) \
+	SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", #x, SPLIT_NS(rt_rq->x))
+
+	P(rt_nr_running);
+	P(rt_throttled);
+	PN(rt_time);
+	PN(rt_runtime);
+
+#undef PN
+#undef P
+}
+
+extern __read_mostly int sched_clock_running;
+
+static void print_cpu(struct seq_file *m, int cpu)
+{
+	struct rq *rq = cpu_rq(cpu);
+	unsigned long flags;
+
+#ifdef CONFIG_X86
+	{
+		unsigned int freq = cpu_khz ? : 1;
+
+		SEQ_printf(m, "\ncpu#%d, %u.%03u MHz\n",
+			   cpu, freq / 1000, (freq % 1000));
+	}
+#else
+	SEQ_printf(m, "\ncpu#%d\n", cpu);
+#endif
+
+#define P(x) \
+	SEQ_printf(m, "  .%-30s: %Ld\n", #x, (long long)(rq->x))
+#define PN(x) \
+	SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", #x, SPLIT_NS(rq->x))
+
+	P(nr_running);
+	SEQ_printf(m, "  .%-30s: %lu\n", "load",
+		   rq->load.weight);
+	P(nr_switches);
+	P(nr_load_updates);
+	P(nr_uninterruptible);
+	PN(next_balance);
+	P(curr->pid);
+	PN(clock);
+	P(cpu_load[0]);
+	P(cpu_load[1]);
+	P(cpu_load[2]);
+	P(cpu_load[3]);
+	P(cpu_load[4]);
+#undef P
+#undef PN
+
+#ifdef CONFIG_SCHEDSTATS
+#define P(n) SEQ_printf(m, "  .%-30s: %d\n", #n, rq->n);
+#define P64(n) SEQ_printf(m, "  .%-30s: %Ld\n", #n, rq->n);
+
+	P(yld_count);
+
+	P(sched_switch);
+	P(sched_count);
+	P(sched_goidle);
+#ifdef CONFIG_SMP
+	P64(avg_idle);
+#endif
+
+	P(ttwu_count);
+	P(ttwu_local);
+
+#undef P
+#undef P64
+#endif
+	spin_lock_irqsave(&sched_debug_lock, flags);
+	print_cfs_stats(m, cpu);
+	print_rt_stats(m, cpu);
+
+	rcu_read_lock();
+	print_rq(m, rq, cpu);
+	rcu_read_unlock();
+	spin_unlock_irqrestore(&sched_debug_lock, flags);
+}
+
+static const char *sched_tunable_scaling_names[] = {
+	"none",
+	"logaritmic",
+	"linear"
+};
+
+static int sched_debug_show(struct seq_file *m, void *v)
+{
+	u64 ktime, sched_clk, cpu_clk;
+	unsigned long flags;
+	int cpu;
+
+	local_irq_save(flags);
+	ktime = ktime_to_ns(ktime_get());
+	sched_clk = sched_clock();
+	cpu_clk = local_clock();
+	local_irq_restore(flags);
+
+	SEQ_printf(m, "Sched Debug Version: v0.10, %s %.*s\n",
+		init_utsname()->release,
+		(int)strcspn(init_utsname()->version, " "),
+		init_utsname()->version);
+
+#define P(x) \
+	SEQ_printf(m, "%-40s: %Ld\n", #x, (long long)(x))
+#define PN(x) \
+	SEQ_printf(m, "%-40s: %Ld.%06ld\n", #x, SPLIT_NS(x))
+	PN(ktime);
+	PN(sched_clk);
+	PN(cpu_clk);
+	P(jiffies);
+#ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
+	P(sched_clock_stable);
+#endif
+#undef PN
+#undef P
+
+	SEQ_printf(m, "\n");
+	SEQ_printf(m, "sysctl_sched\n");
+
+#define P(x) \
+	SEQ_printf(m, "  .%-40s: %Ld\n", #x, (long long)(x))
+#define PN(x) \
+	SEQ_printf(m, "  .%-40s: %Ld.%06ld\n", #x, SPLIT_NS(x))
+	PN(sysctl_sched_latency);
+	PN(sysctl_sched_min_granularity);
+	PN(sysctl_sched_wakeup_granularity);
+	P(sysctl_sched_child_runs_first);
+	P(sysctl_sched_features);
+#undef PN
+#undef P
+
+	SEQ_printf(m, "  .%-40s: %d (%s)\n", "sysctl_sched_tunable_scaling",
+		sysctl_sched_tunable_scaling,
+		sched_tunable_scaling_names[sysctl_sched_tunable_scaling]);
+
+	for_each_online_cpu(cpu)
+		print_cpu(m, cpu);
+
+	SEQ_printf(m, "\n");
+
+	return 0;
+}
+
+void sysrq_sched_debug_show(void)
+{
+	sched_debug_show(NULL, NULL);
+}
+
+static int sched_debug_open(struct inode *inode, struct file *filp)
+{
+	return single_open(filp, sched_debug_show, NULL);
+}
+
+static const struct file_operations sched_debug_fops = {
+	.open		= sched_debug_open,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+
+static int __init init_sched_debug_procfs(void)
+{
+	struct proc_dir_entry *pe;
+
+	pe = proc_create("sched_debug", 0444, NULL, &sched_debug_fops);
+	if (!pe)
+		return -ENOMEM;
+	return 0;
+}
+
+__initcall(init_sched_debug_procfs);
+
+void proc_sched_show_task(struct task_struct *p, struct seq_file *m)
+{
+	unsigned long nr_switches;
+
+	SEQ_printf(m, "%s (%d, #threads: %d)\n", p->comm, p->pid,
+						get_nr_threads(p));
+	SEQ_printf(m,
+		"---------------------------------------------------------\n");
+#define __P(F) \
+	SEQ_printf(m, "%-35s:%21Ld\n", #F, (long long)F)
+#define P(F) \
+	SEQ_printf(m, "%-35s:%21Ld\n", #F, (long long)p->F)
+#define __PN(F) \
+	SEQ_printf(m, "%-35s:%14Ld.%06ld\n", #F, SPLIT_NS((long long)F))
+#define PN(F) \
+	SEQ_printf(m, "%-35s:%14Ld.%06ld\n", #F, SPLIT_NS((long long)p->F))
+
+	PN(se.exec_start);
+	PN(se.vruntime);
+	PN(se.sum_exec_runtime);
+
+	nr_switches = p->nvcsw + p->nivcsw;
+
+#ifdef CONFIG_SCHEDSTATS
+	PN(se.statistics.wait_start);
+	PN(se.statistics.sleep_start);
+	PN(se.statistics.block_start);
+	PN(se.statistics.sleep_max);
+	PN(se.statistics.block_max);
+	PN(se.statistics.exec_max);
+	PN(se.statistics.slice_max);
+	PN(se.statistics.wait_max);
+	PN(se.statistics.wait_sum);
+	P(se.statistics.wait_count);
+	PN(se.statistics.iowait_sum);
+	P(se.statistics.iowait_count);
+	P(se.nr_migrations);
+	P(se.statistics.nr_migrations_cold);
+	P(se.statistics.nr_failed_migrations_affine);
+	P(se.statistics.nr_failed_migrations_running);
+	P(se.statistics.nr_failed_migrations_hot);
+	P(se.statistics.nr_forced_migrations);
+	P(se.statistics.nr_wakeups);
+	P(se.statistics.nr_wakeups_sync);
+	P(se.statistics.nr_wakeups_migrate);
+	P(se.statistics.nr_wakeups_local);
+	P(se.statistics.nr_wakeups_remote);
+	P(se.statistics.nr_wakeups_affine);
+	P(se.statistics.nr_wakeups_affine_attempts);
+	P(se.statistics.nr_wakeups_passive);
+	P(se.statistics.nr_wakeups_idle);
+
+	{
+		u64 avg_atom, avg_per_cpu;
+
+		avg_atom = p->se.sum_exec_runtime;
+		if (nr_switches)
+			do_div(avg_atom, nr_switches);
+		else
+			avg_atom = -1LL;
+
+		avg_per_cpu = p->se.sum_exec_runtime;
+		if (p->se.nr_migrations) {
+			avg_per_cpu = div64_u64(avg_per_cpu,
+						p->se.nr_migrations);
+		} else {
+			avg_per_cpu = -1LL;
+		}
+
+		__PN(avg_atom);
+		__PN(avg_per_cpu);
+	}
+#endif
+	__P(nr_switches);
+	SEQ_printf(m, "%-35s:%21Ld\n",
+		   "nr_voluntary_switches", (long long)p->nvcsw);
+	SEQ_printf(m, "%-35s:%21Ld\n",
+		   "nr_involuntary_switches", (long long)p->nivcsw);
+
+	P(se.load.weight);
+	P(policy);
+	P(prio);
+#undef PN
+#undef __PN
+#undef P
+#undef __P
+
+	{
+		unsigned int this_cpu = raw_smp_processor_id();
+		u64 t0, t1;
+
+		t0 = cpu_clock(this_cpu);
+		t1 = cpu_clock(this_cpu);
+		SEQ_printf(m, "%-35s:%21Ld\n",
+			   "clock-delta", (long long)(t1-t0));
+	}
+}
+
+void proc_sched_set_task(struct task_struct *p)
+{
+#ifdef CONFIG_SCHEDSTATS
+	memset(&p->se.statistics, 0, sizeof(p->se.statistics));
+#endif
+}
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
new file mode 100644
index 00000000000..84adb2d66cb
--- /dev/null
+++ b/kernel/sched/fair.c
@@ -0,0 +1,5596 @@
+/*
+ * Completely Fair Scheduling (CFS) Class (SCHED_NORMAL/SCHED_BATCH)
+ *
+ *  Copyright (C) 2007 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
+ *
+ *  Interactivity improvements by Mike Galbraith
+ *  (C) 2007 Mike Galbraith <efault@gmx.de>
+ *
+ *  Various enhancements by Dmitry Adamushko.
+ *  (C) 2007 Dmitry Adamushko <dmitry.adamushko@gmail.com>
+ *
+ *  Group scheduling enhancements by Srivatsa Vaddagiri
+ *  Copyright IBM Corporation, 2007
+ *  Author: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
+ *
+ *  Scaled math optimizations by Thomas Gleixner
+ *  Copyright (C) 2007, Thomas Gleixner <tglx@linutronix.de>
+ *
+ *  Adaptive scheduling granularity, math enhancements by Peter Zijlstra
+ *  Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
+ */
+
+#include <linux/latencytop.h>
+#include <linux/sched.h>
+#include <linux/cpumask.h>
+#include <linux/slab.h>
+#include <linux/profile.h>
+#include <linux/interrupt.h>
+
+#include <trace/events/sched.h>
+
+#include "sched.h"
+
+/*
+ * Targeted preemption latency for CPU-bound tasks:
+ * (default: 6ms * (1 + ilog(ncpus)), units: nanoseconds)
+ *
+ * NOTE: this latency value is not the same as the concept of
+ * 'timeslice length' - timeslices in CFS are of variable length
+ * and have no persistent notion like in traditional, time-slice
+ * based scheduling concepts.
+ *
+ * (to see the precise effective timeslice length of your workload,
+ *  run vmstat and monitor the context-switches (cs) field)
+ */
+unsigned int sysctl_sched_latency = 6000000ULL;
+unsigned int normalized_sysctl_sched_latency = 6000000ULL;
+
+/*
+ * The initial- and re-scaling of tunables is configurable
+ * (default SCHED_TUNABLESCALING_LOG = *(1+ilog(ncpus))
+ *
+ * Options are:
+ * SCHED_TUNABLESCALING_NONE - unscaled, always *1
+ * SCHED_TUNABLESCALING_LOG - scaled logarithmical, *1+ilog(ncpus)
+ * SCHED_TUNABLESCALING_LINEAR - scaled linear, *ncpus
+ */
+enum sched_tunable_scaling sysctl_sched_tunable_scaling
+	= SCHED_TUNABLESCALING_LOG;
+
+/*
+ * Minimal preemption granularity for CPU-bound tasks:
+ * (default: 0.75 msec * (1 + ilog(ncpus)), units: nanoseconds)
+ */
+unsigned int sysctl_sched_min_granularity = 750000ULL;
+unsigned int normalized_sysctl_sched_min_granularity = 750000ULL;
+
+/*
+ * is kept at sysctl_sched_latency / sysctl_sched_min_granularity
+ */
+static unsigned int sched_nr_latency = 8;
+
+/*
+ * After fork, child runs first. If set to 0 (default) then
+ * parent will (try to) run first.
+ */
+unsigned int sysctl_sched_child_runs_first __read_mostly;
+
+/*
+ * SCHED_OTHER wake-up granularity.
+ * (default: 1 msec * (1 + ilog(ncpus)), units: nanoseconds)
+ *
+ * This option delays the preemption effects of decoupled workloads
+ * and reduces their over-scheduling. Synchronous workloads will still
+ * have immediate wakeup/sleep latencies.
+ */
+unsigned int sysctl_sched_wakeup_granularity = 1000000UL;
+unsigned int normalized_sysctl_sched_wakeup_granularity = 1000000UL;
+
+const_debug unsigned int sysctl_sched_migration_cost = 500000UL;
+
+/*
+ * The exponential sliding  window over which load is averaged for shares
+ * distribution.
+ * (default: 10msec)
+ */
+unsigned int __read_mostly sysctl_sched_shares_window = 10000000UL;
+
+#ifdef CONFIG_CFS_BANDWIDTH
+/*
+ * Amount of runtime to allocate from global (tg) to local (per-cfs_rq) pool
+ * each time a cfs_rq requests quota.
+ *
+ * Note: in the case that the slice exceeds the runtime remaining (either due
+ * to consumption or the quota being specified to be smaller than the slice)
+ * we will always only issue the remaining available time.
+ *
+ * default: 5 msec, units: microseconds
+  */
+unsigned int sysctl_sched_cfs_bandwidth_slice = 5000UL;
+#endif
+
+/*
+ * Increase the granularity value when there are more CPUs,
+ * because with more CPUs the 'effective latency' as visible
+ * to users decreases. But the relationship is not linear,
+ * so pick a second-best guess by going with the log2 of the
+ * number of CPUs.
+ *
+ * This idea comes from the SD scheduler of Con Kolivas:
+ */
+static int get_update_sysctl_factor(void)
+{
+	unsigned int cpus = min_t(int, num_online_cpus(), 8);
+	unsigned int factor;
+
+	switch (sysctl_sched_tunable_scaling) {
+	case SCHED_TUNABLESCALING_NONE:
+		factor = 1;
+		break;
+	case SCHED_TUNABLESCALING_LINEAR:
+		factor = cpus;
+		break;
+	case SCHED_TUNABLESCALING_LOG:
+	default:
+		factor = 1 + ilog2(cpus);
+		break;
+	}
+
+	return factor;
+}
+
+static void update_sysctl(void)
+{
+	unsigned int factor = get_update_sysctl_factor();
+
+#define SET_SYSCTL(name) \
+	(sysctl_##name = (factor) * normalized_sysctl_##name)
+	SET_SYSCTL(sched_min_granularity);
+	SET_SYSCTL(sched_latency);
+	SET_SYSCTL(sched_wakeup_granularity);
+#undef SET_SYSCTL
+}
+
+void sched_init_granularity(void)
+{
+	update_sysctl();
+}
+
+#if BITS_PER_LONG == 32
+# define WMULT_CONST	(~0UL)
+#else
+# define WMULT_CONST	(1UL << 32)
+#endif
+
+#define WMULT_SHIFT	32
+
+/*
+ * Shift right and round:
+ */
+#define SRR(x, y) (((x) + (1UL << ((y) - 1))) >> (y))
+
+/*
+ * delta *= weight / lw
+ */
+static unsigned long
+calc_delta_mine(unsigned long delta_exec, unsigned long weight,
+		struct load_weight *lw)
+{
+	u64 tmp;
+
+	/*
+	 * weight can be less than 2^SCHED_LOAD_RESOLUTION for task group sched
+	 * entities since MIN_SHARES = 2. Treat weight as 1 if less than
+	 * 2^SCHED_LOAD_RESOLUTION.
+	 */
+	if (likely(weight > (1UL << SCHED_LOAD_RESOLUTION)))
+		tmp = (u64)delta_exec * scale_load_down(weight);
+	else
+		tmp = (u64)delta_exec;
+
+	if (!lw->inv_weight) {
+		unsigned long w = scale_load_down(lw->weight);
+
+		if (BITS_PER_LONG > 32 && unlikely(w >= WMULT_CONST))
+			lw->inv_weight = 1;
+		else if (unlikely(!w))
+			lw->inv_weight = WMULT_CONST;
+		else
+			lw->inv_weight = WMULT_CONST / w;
+	}
+
+	/*
+	 * Check whether we'd overflow the 64-bit multiplication:
+	 */
+	if (unlikely(tmp > WMULT_CONST))
+		tmp = SRR(SRR(tmp, WMULT_SHIFT/2) * lw->inv_weight,
+			WMULT_SHIFT/2);
+	else
+		tmp = SRR(tmp * lw->inv_weight, WMULT_SHIFT);
+
+	return (unsigned long)min(tmp, (u64)(unsigned long)LONG_MAX);
+}
+
+
+const struct sched_class fair_sched_class;
+
+/**************************************************************
+ * CFS operations on generic schedulable entities:
+ */
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+
+/* cpu runqueue to which this cfs_rq is attached */
+static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
+{
+	return cfs_rq->rq;
+}
+
+/* An entity is a task if it doesn't "own" a runqueue */
+#define entity_is_task(se)	(!se->my_q)
+
+static inline struct task_struct *task_of(struct sched_entity *se)
+{
+#ifdef CONFIG_SCHED_DEBUG
+	WARN_ON_ONCE(!entity_is_task(se));
+#endif
+	return container_of(se, struct task_struct, se);
+}
+
+/* Walk up scheduling entities hierarchy */
+#define for_each_sched_entity(se) \
+		for (; se; se = se->parent)
+
+static inline struct cfs_rq *task_cfs_rq(struct task_struct *p)
+{
+	return p->se.cfs_rq;
+}
+
+/* runqueue on which this entity is (to be) queued */
+static inline struct cfs_rq *cfs_rq_of(struct sched_entity *se)
+{
+	return se->cfs_rq;
+}
+
+/* runqueue "owned" by this group */
+static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
+{
+	return grp->my_q;
+}
+
+static inline void list_add_leaf_cfs_rq(struct cfs_rq *cfs_rq)
+{
+	if (!cfs_rq->on_list) {
+		/*
+		 * Ensure we either appear before our parent (if already
+		 * enqueued) or force our parent to appear after us when it is
+		 * enqueued.  The fact that we always enqueue bottom-up
+		 * reduces this to two cases.
+		 */
+		if (cfs_rq->tg->parent &&
+		    cfs_rq->tg->parent->cfs_rq[cpu_of(rq_of(cfs_rq))]->on_list) {
+			list_add_rcu(&cfs_rq->leaf_cfs_rq_list,
+				&rq_of(cfs_rq)->leaf_cfs_rq_list);
+		} else {
+			list_add_tail_rcu(&cfs_rq->leaf_cfs_rq_list,
+				&rq_of(cfs_rq)->leaf_cfs_rq_list);
+		}
+
+		cfs_rq->on_list = 1;
+	}
+}
+
+static inline void list_del_leaf_cfs_rq(struct cfs_rq *cfs_rq)
+{
+	if (cfs_rq->on_list) {
+		list_del_rcu(&cfs_rq->leaf_cfs_rq_list);
+		cfs_rq->on_list = 0;
+	}
+}
+
+/* Iterate thr' all leaf cfs_rq's on a runqueue */
+#define for_each_leaf_cfs_rq(rq, cfs_rq) \
+	list_for_each_entry_rcu(cfs_rq, &rq->leaf_cfs_rq_list, leaf_cfs_rq_list)
+
+/* Do the two (enqueued) entities belong to the same group ? */
+static inline int
+is_same_group(struct sched_entity *se, struct sched_entity *pse)
+{
+	if (se->cfs_rq == pse->cfs_rq)
+		return 1;
+
+	return 0;
+}
+
+static inline struct sched_entity *parent_entity(struct sched_entity *se)
+{
+	return se->parent;
+}
+
+/* return depth at which a sched entity is present in the hierarchy */
+static inline int depth_se(struct sched_entity *se)
+{
+	int depth = 0;
+
+	for_each_sched_entity(se)
+		depth++;
+
+	return depth;
+}
+
+static void
+find_matching_se(struct sched_entity **se, struct sched_entity **pse)
+{
+	int se_depth, pse_depth;
+
+	/*
+	 * preemption test can be made between sibling entities who are in the
+	 * same cfs_rq i.e who have a common parent. Walk up the hierarchy of
+	 * both tasks until we find their ancestors who are siblings of common
+	 * parent.
+	 */
+
+	/* First walk up until both entities are at same depth */
+	se_depth = depth_se(*se);
+	pse_depth = depth_se(*pse);
+
+	while (se_depth > pse_depth) {
+		se_depth--;
+		*se = parent_entity(*se);
+	}
+
+	while (pse_depth > se_depth) {
+		pse_depth--;
+		*pse = parent_entity(*pse);
+	}
+
+	while (!is_same_group(*se, *pse)) {
+		*se = parent_entity(*se);
+		*pse = parent_entity(*pse);
+	}
+}
+
+#else	/* !CONFIG_FAIR_GROUP_SCHED */
+
+static inline struct task_struct *task_of(struct sched_entity *se)
+{
+	return container_of(se, struct task_struct, se);
+}
+
+static inline struct rq *rq_of(struct cfs_rq *cfs_rq)
+{
+	return container_of(cfs_rq, struct rq, cfs);
+}
+
+#define entity_is_task(se)	1
+
+#define for_each_sched_entity(se) \
+		for (; se; se = NULL)
+
+static inline struct cfs_rq *task_cfs_rq(struct task_struct *p)
+{
+	return &task_rq(p)->cfs;
+}
+
+static inline struct cfs_rq *cfs_rq_of(struct sched_entity *se)
+{
+	struct task_struct *p = task_of(se);
+	struct rq *rq = task_rq(p);
+
+	return &rq->cfs;
+}
+
+/* runqueue "owned" by this group */
+static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
+{
+	return NULL;
+}
+
+static inline void list_add_leaf_cfs_rq(struct cfs_rq *cfs_rq)
+{
+}
+
+static inline void list_del_leaf_cfs_rq(struct cfs_rq *cfs_rq)
+{
+}
+
+#define for_each_leaf_cfs_rq(rq, cfs_rq) \
+		for (cfs_rq = &rq->cfs; cfs_rq; cfs_rq = NULL)
+
+static inline int
+is_same_group(struct sched_entity *se, struct sched_entity *pse)
+{
+	return 1;
+}
+
+static inline struct sched_entity *parent_entity(struct sched_entity *se)
+{
+	return NULL;
+}
+
+static inline void
+find_matching_se(struct sched_entity **se, struct sched_entity **pse)
+{
+}
+
+#endif	/* CONFIG_FAIR_GROUP_SCHED */
+
+static void account_cfs_rq_runtime(struct cfs_rq *cfs_rq,
+				   unsigned long delta_exec);
+
+/**************************************************************
+ * Scheduling class tree data structure manipulation methods:
+ */
+
+static inline u64 max_vruntime(u64 min_vruntime, u64 vruntime)
+{
+	s64 delta = (s64)(vruntime - min_vruntime);
+	if (delta > 0)
+		min_vruntime = vruntime;
+
+	return min_vruntime;
+}
+
+static inline u64 min_vruntime(u64 min_vruntime, u64 vruntime)
+{
+	s64 delta = (s64)(vruntime - min_vruntime);
+	if (delta < 0)
+		min_vruntime = vruntime;
+
+	return min_vruntime;
+}
+
+static inline int entity_before(struct sched_entity *a,
+				struct sched_entity *b)
+{
+	return (s64)(a->vruntime - b->vruntime) < 0;
+}
+
+static void update_min_vruntime(struct cfs_rq *cfs_rq)
+{
+	u64 vruntime = cfs_rq->min_vruntime;
+
+	if (cfs_rq->curr)
+		vruntime = cfs_rq->curr->vruntime;
+
+	if (cfs_rq->rb_leftmost) {
+		struct sched_entity *se = rb_entry(cfs_rq->rb_leftmost,
+						   struct sched_entity,
+						   run_node);
+
+		if (!cfs_rq->curr)
+			vruntime = se->vruntime;
+		else
+			vruntime = min_vruntime(vruntime, se->vruntime);
+	}
+
+	cfs_rq->min_vruntime = max_vruntime(cfs_rq->min_vruntime, vruntime);
+#ifndef CONFIG_64BIT
+	smp_wmb();
+	cfs_rq->min_vruntime_copy = cfs_rq->min_vruntime;
+#endif
+}
+
+/*
+ * Enqueue an entity into the rb-tree:
+ */
+static void __enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
+	struct rb_node **link = &cfs_rq->tasks_timeline.rb_node;
+	struct rb_node *parent = NULL;
+	struct sched_entity *entry;
+	int leftmost = 1;
+
+	/*
+	 * Find the right place in the rbtree:
+	 */
+	while (*link) {
+		parent = *link;
+		entry = rb_entry(parent, struct sched_entity, run_node);
+		/*
+		 * We dont care about collisions. Nodes with
+		 * the same key stay together.
+		 */
+		if (entity_before(se, entry)) {
+			link = &parent->rb_left;
+		} else {
+			link = &parent->rb_right;
+			leftmost = 0;
+		}
+	}
+
+	/*
+	 * Maintain a cache of leftmost tree entries (it is frequently
+	 * used):
+	 */
+	if (leftmost)
+		cfs_rq->rb_leftmost = &se->run_node;
+
+	rb_link_node(&se->run_node, parent, link);
+	rb_insert_color(&se->run_node, &cfs_rq->tasks_timeline);
+}
+
+static void __dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
+	if (cfs_rq->rb_leftmost == &se->run_node) {
+		struct rb_node *next_node;
+
+		next_node = rb_next(&se->run_node);
+		cfs_rq->rb_leftmost = next_node;
+	}
+
+	rb_erase(&se->run_node, &cfs_rq->tasks_timeline);
+}
+
+struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq)
+{
+	struct rb_node *left = cfs_rq->rb_leftmost;
+
+	if (!left)
+		return NULL;
+
+	return rb_entry(left, struct sched_entity, run_node);
+}
+
+static struct sched_entity *__pick_next_entity(struct sched_entity *se)
+{
+	struct rb_node *next = rb_next(&se->run_node);
+
+	if (!next)
+		return NULL;
+
+	return rb_entry(next, struct sched_entity, run_node);
+}
+
+#ifdef CONFIG_SCHED_DEBUG
+struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq)
+{
+	struct rb_node *last = rb_last(&cfs_rq->tasks_timeline);
+
+	if (!last)
+		return NULL;
+
+	return rb_entry(last, struct sched_entity, run_node);
+}
+
+/**************************************************************
+ * Scheduling class statistics methods:
+ */
+
+int sched_proc_update_handler(struct ctl_table *table, int write,
+		void __user *buffer, size_t *lenp,
+		loff_t *ppos)
+{
+	int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
+	int factor = get_update_sysctl_factor();
+
+	if (ret || !write)
+		return ret;
+
+	sched_nr_latency = DIV_ROUND_UP(sysctl_sched_latency,
+					sysctl_sched_min_granularity);
+
+#define WRT_SYSCTL(name) \
+	(normalized_sysctl_##name = sysctl_##name / (factor))
+	WRT_SYSCTL(sched_min_granularity);
+	WRT_SYSCTL(sched_latency);
+	WRT_SYSCTL(sched_wakeup_granularity);
+#undef WRT_SYSCTL
+
+	return 0;
+}
+#endif
+
+/*
+ * delta /= w
+ */
+static inline unsigned long
+calc_delta_fair(unsigned long delta, struct sched_entity *se)
+{
+	if (unlikely(se->load.weight != NICE_0_LOAD))
+		delta = calc_delta_mine(delta, NICE_0_LOAD, &se->load);
+
+	return delta;
+}
+
+/*
+ * The idea is to set a period in which each task runs once.
+ *
+ * When there are too many tasks (sysctl_sched_nr_latency) we have to stretch
+ * this period because otherwise the slices get too small.
+ *
+ * p = (nr <= nl) ? l : l*nr/nl
+ */
+static u64 __sched_period(unsigned long nr_running)
+{
+	u64 period = sysctl_sched_latency;
+	unsigned long nr_latency = sched_nr_latency;
+
+	if (unlikely(nr_running > nr_latency)) {
+		period = sysctl_sched_min_granularity;
+		period *= nr_running;
+	}
+
+	return period;
+}
+
+/*
+ * We calculate the wall-time slice from the period by taking a part
+ * proportional to the weight.
+ *
+ * s = p*P[w/rw]
+ */
+static u64 sched_slice(struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
+	u64 slice = __sched_period(cfs_rq->nr_running + !se->on_rq);
+
+	for_each_sched_entity(se) {
+		struct load_weight *load;
+		struct load_weight lw;
+
+		cfs_rq = cfs_rq_of(se);
+		load = &cfs_rq->load;
+
+		if (unlikely(!se->on_rq)) {
+			lw = cfs_rq->load;
+
+			update_load_add(&lw, se->load.weight);
+			load = &lw;
+		}
+		slice = calc_delta_mine(slice, se->load.weight, load);
+	}
+	return slice;
+}
+
+/*
+ * We calculate the vruntime slice of a to be inserted task
+ *
+ * vs = s/w
+ */
+static u64 sched_vslice(struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
+	return calc_delta_fair(sched_slice(cfs_rq, se), se);
+}
+
+static void update_cfs_load(struct cfs_rq *cfs_rq, int global_update);
+static void update_cfs_shares(struct cfs_rq *cfs_rq);
+
+/*
+ * Update the current task's runtime statistics. Skip current tasks that
+ * are not in our scheduling class.
+ */
+static inline void
+__update_curr(struct cfs_rq *cfs_rq, struct sched_entity *curr,
+	      unsigned long delta_exec)
+{
+	unsigned long delta_exec_weighted;
+
+	schedstat_set(curr->statistics.exec_max,
+		      max((u64)delta_exec, curr->statistics.exec_max));
+
+	curr->sum_exec_runtime += delta_exec;
+	schedstat_add(cfs_rq, exec_clock, delta_exec);
+	delta_exec_weighted = calc_delta_fair(delta_exec, curr);
+
+	curr->vruntime += delta_exec_weighted;
+	update_min_vruntime(cfs_rq);
+
+#if defined CONFIG_SMP && defined CONFIG_FAIR_GROUP_SCHED
+	cfs_rq->load_unacc_exec_time += delta_exec;
+#endif
+}
+
+static void update_curr(struct cfs_rq *cfs_rq)
+{
+	struct sched_entity *curr = cfs_rq->curr;
+	u64 now = rq_of(cfs_rq)->clock_task;
+	unsigned long delta_exec;
+
+	if (unlikely(!curr))
+		return;
+
+	/*
+	 * Get the amount of time the current task was running
+	 * since the last time we changed load (this cannot
+	 * overflow on 32 bits):
+	 */
+	delta_exec = (unsigned long)(now - curr->exec_start);
+	if (!delta_exec)
+		return;
+
+	__update_curr(cfs_rq, curr, delta_exec);
+	curr->exec_start = now;
+
+	if (entity_is_task(curr)) {
+		struct task_struct *curtask = task_of(curr);
+
+		trace_sched_stat_runtime(curtask, delta_exec, curr->vruntime);
+		cpuacct_charge(curtask, delta_exec);
+		account_group_exec_runtime(curtask, delta_exec);
+	}
+
+	account_cfs_rq_runtime(cfs_rq, delta_exec);
+}
+
+static inline void
+update_stats_wait_start(struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
+	schedstat_set(se->statistics.wait_start, rq_of(cfs_rq)->clock);
+}
+
+/*
+ * Task is being enqueued - update stats:
+ */
+static void update_stats_enqueue(struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
+	/*
+	 * Are we enqueueing a waiting task? (for current tasks
+	 * a dequeue/enqueue event is a NOP)
+	 */
+	if (se != cfs_rq->curr)
+		update_stats_wait_start(cfs_rq, se);
+}
+
+static void
+update_stats_wait_end(struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
+	schedstat_set(se->statistics.wait_max, max(se->statistics.wait_max,
+			rq_of(cfs_rq)->clock - se->statistics.wait_start));
+	schedstat_set(se->statistics.wait_count, se->statistics.wait_count + 1);
+	schedstat_set(se->statistics.wait_sum, se->statistics.wait_sum +
+			rq_of(cfs_rq)->clock - se->statistics.wait_start);
+#ifdef CONFIG_SCHEDSTATS
+	if (entity_is_task(se)) {
+		trace_sched_stat_wait(task_of(se),
+			rq_of(cfs_rq)->clock - se->statistics.wait_start);
+	}
+#endif
+	schedstat_set(se->statistics.wait_start, 0);
+}
+
+static inline void
+update_stats_dequeue(struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
+	/*
+	 * Mark the end of the wait period if dequeueing a
+	 * waiting task:
+	 */
+	if (se != cfs_rq->curr)
+		update_stats_wait_end(cfs_rq, se);
+}
+
+/*
+ * We are picking a new current task - update its stats:
+ */
+static inline void
+update_stats_curr_start(struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
+	/*
+	 * We are starting a new run period:
+	 */
+	se->exec_start = rq_of(cfs_rq)->clock_task;
+}
+
+/**************************************************
+ * Scheduling class queueing methods:
+ */
+
+#if defined CONFIG_SMP && defined CONFIG_FAIR_GROUP_SCHED
+static void
+add_cfs_task_weight(struct cfs_rq *cfs_rq, unsigned long weight)
+{
+	cfs_rq->task_weight += weight;
+}
+#else
+static inline void
+add_cfs_task_weight(struct cfs_rq *cfs_rq, unsigned long weight)
+{
+}
+#endif
+
+static void
+account_entity_enqueue(struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
+	update_load_add(&cfs_rq->load, se->load.weight);
+	if (!parent_entity(se))
+		update_load_add(&rq_of(cfs_rq)->load, se->load.weight);
+	if (entity_is_task(se)) {
+		add_cfs_task_weight(cfs_rq, se->load.weight);
+		list_add(&se->group_node, &cfs_rq->tasks);
+	}
+	cfs_rq->nr_running++;
+}
+
+static void
+account_entity_dequeue(struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
+	update_load_sub(&cfs_rq->load, se->load.weight);
+	if (!parent_entity(se))
+		update_load_sub(&rq_of(cfs_rq)->load, se->load.weight);
+	if (entity_is_task(se)) {
+		add_cfs_task_weight(cfs_rq, -se->load.weight);
+		list_del_init(&se->group_node);
+	}
+	cfs_rq->nr_running--;
+}
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+/* we need this in update_cfs_load and load-balance functions below */
+static inline int throttled_hierarchy(struct cfs_rq *cfs_rq);
+# ifdef CONFIG_SMP
+static void update_cfs_rq_load_contribution(struct cfs_rq *cfs_rq,
+					    int global_update)
+{
+	struct task_group *tg = cfs_rq->tg;
+	long load_avg;
+
+	load_avg = div64_u64(cfs_rq->load_avg, cfs_rq->load_period+1);
+	load_avg -= cfs_rq->load_contribution;
+
+	if (global_update || abs(load_avg) > cfs_rq->load_contribution / 8) {
+		atomic_add(load_avg, &tg->load_weight);
+		cfs_rq->load_contribution += load_avg;
+	}
+}
+
+static void update_cfs_load(struct cfs_rq *cfs_rq, int global_update)
+{
+	u64 period = sysctl_sched_shares_window;
+	u64 now, delta;
+	unsigned long load = cfs_rq->load.weight;
+
+	if (cfs_rq->tg == &root_task_group || throttled_hierarchy(cfs_rq))
+		return;
+
+	now = rq_of(cfs_rq)->clock_task;
+	delta = now - cfs_rq->load_stamp;
+
+	/* truncate load history at 4 idle periods */
+	if (cfs_rq->load_stamp > cfs_rq->load_last &&
+	    now - cfs_rq->load_last > 4 * period) {
+		cfs_rq->load_period = 0;
+		cfs_rq->load_avg = 0;
+		delta = period - 1;
+	}
+
+	cfs_rq->load_stamp = now;
+	cfs_rq->load_unacc_exec_time = 0;
+	cfs_rq->load_period += delta;
+	if (load) {
+		cfs_rq->load_last = now;
+		cfs_rq->load_avg += delta * load;
+	}
+
+	/* consider updating load contribution on each fold or truncate */
+	if (global_update || cfs_rq->load_period > period
+	    || !cfs_rq->load_period)
+		update_cfs_rq_load_contribution(cfs_rq, global_update);
+
+	while (cfs_rq->load_period > period) {
+		/*
+		 * Inline assembly required to prevent the compiler
+		 * optimising this loop into a divmod call.
+		 * See __iter_div_u64_rem() for another example of this.
+		 */
+		asm("" : "+rm" (cfs_rq->load_period));
+		cfs_rq->load_period /= 2;
+		cfs_rq->load_avg /= 2;
+	}
+
+	if (!cfs_rq->curr && !cfs_rq->nr_running && !cfs_rq->load_avg)
+		list_del_leaf_cfs_rq(cfs_rq);
+}
+
+static inline long calc_tg_weight(struct task_group *tg, struct cfs_rq *cfs_rq)
+{
+	long tg_weight;
+
+	/*
+	 * Use this CPU's actual weight instead of the last load_contribution
+	 * to gain a more accurate current total weight. See
+	 * update_cfs_rq_load_contribution().
+	 */
+	tg_weight = atomic_read(&tg->load_weight);
+	tg_weight -= cfs_rq->load_contribution;
+	tg_weight += cfs_rq->load.weight;
+
+	return tg_weight;
+}
+
+static long calc_cfs_shares(struct cfs_rq *cfs_rq, struct task_group *tg)
+{
+	long tg_weight, load, shares;
+
+	tg_weight = calc_tg_weight(tg, cfs_rq);
+	load = cfs_rq->load.weight;
+
+	shares = (tg->shares * load);
+	if (tg_weight)
+		shares /= tg_weight;
+
+	if (shares < MIN_SHARES)
+		shares = MIN_SHARES;
+	if (shares > tg->shares)
+		shares = tg->shares;
+
+	return shares;
+}
+
+static void update_entity_shares_tick(struct cfs_rq *cfs_rq)
+{
+	if (cfs_rq->load_unacc_exec_time > sysctl_sched_shares_window) {
+		update_cfs_load(cfs_rq, 0);
+		update_cfs_shares(cfs_rq);
+	}
+}
+# else /* CONFIG_SMP */
+static void update_cfs_load(struct cfs_rq *cfs_rq, int global_update)
+{
+}
+
+static inline long calc_cfs_shares(struct cfs_rq *cfs_rq, struct task_group *tg)
+{
+	return tg->shares;
+}
+
+static inline void update_entity_shares_tick(struct cfs_rq *cfs_rq)
+{
+}
+# endif /* CONFIG_SMP */
+static void reweight_entity(struct cfs_rq *cfs_rq, struct sched_entity *se,
+			    unsigned long weight)
+{
+	if (se->on_rq) {
+		/* commit outstanding execution time */
+		if (cfs_rq->curr == se)
+			update_curr(cfs_rq);
+		account_entity_dequeue(cfs_rq, se);
+	}
+
+	update_load_set(&se->load, weight);
+
+	if (se->on_rq)
+		account_entity_enqueue(cfs_rq, se);
+}
+
+static void update_cfs_shares(struct cfs_rq *cfs_rq)
+{
+	struct task_group *tg;
+	struct sched_entity *se;
+	long shares;
+
+	tg = cfs_rq->tg;
+	se = tg->se[cpu_of(rq_of(cfs_rq))];
+	if (!se || throttled_hierarchy(cfs_rq))
+		return;
+#ifndef CONFIG_SMP
+	if (likely(se->load.weight == tg->shares))
+		return;
+#endif
+	shares = calc_cfs_shares(cfs_rq, tg);
+
+	reweight_entity(cfs_rq_of(se), se, shares);
+}
+#else /* CONFIG_FAIR_GROUP_SCHED */
+static void update_cfs_load(struct cfs_rq *cfs_rq, int global_update)
+{
+}
+
+static inline void update_cfs_shares(struct cfs_rq *cfs_rq)
+{
+}
+
+static inline void update_entity_shares_tick(struct cfs_rq *cfs_rq)
+{
+}
+#endif /* CONFIG_FAIR_GROUP_SCHED */
+
+static void enqueue_sleeper(struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
+#ifdef CONFIG_SCHEDSTATS
+	struct task_struct *tsk = NULL;
+
+	if (entity_is_task(se))
+		tsk = task_of(se);
+
+	if (se->statistics.sleep_start) {
+		u64 delta = rq_of(cfs_rq)->clock - se->statistics.sleep_start;
+
+		if ((s64)delta < 0)
+			delta = 0;
+
+		if (unlikely(delta > se->statistics.sleep_max))
+			se->statistics.sleep_max = delta;
+
+		se->statistics.sum_sleep_runtime += delta;
+
+		if (tsk) {
+			account_scheduler_latency(tsk, delta >> 10, 1);
+			trace_sched_stat_sleep(tsk, delta);
+		}
+	}
+	if (se->statistics.block_start) {
+		u64 delta = rq_of(cfs_rq)->clock - se->statistics.block_start;
+
+		if ((s64)delta < 0)
+			delta = 0;
+
+		if (unlikely(delta > se->statistics.block_max))
+			se->statistics.block_max = delta;
+
+		se->statistics.sum_sleep_runtime += delta;
+
+		if (tsk) {
+			if (tsk->in_iowait) {
+				se->statistics.iowait_sum += delta;
+				se->statistics.iowait_count++;
+				trace_sched_stat_iowait(tsk, delta);
+			}
+
+			trace_sched_stat_blocked(tsk, delta);
+
+			/*
+			 * Blocking time is in units of nanosecs, so shift by
+			 * 20 to get a milliseconds-range estimation of the
+			 * amount of time that the task spent sleeping:
+			 */
+			if (unlikely(prof_on == SLEEP_PROFILING)) {
+				profile_hits(SLEEP_PROFILING,
+						(void *)get_wchan(tsk),
+						delta >> 20);
+			}
+			account_scheduler_latency(tsk, delta >> 10, 0);
+		}
+	}
+#endif
+}
+
+static void check_spread(struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
+#ifdef CONFIG_SCHED_DEBUG
+	s64 d = se->vruntime - cfs_rq->min_vruntime;
+
+	if (d < 0)
+		d = -d;
+
+	if (d > 3*sysctl_sched_latency)
+		schedstat_inc(cfs_rq, nr_spread_over);
+#endif
+}
+
+static void
+place_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int initial)
+{
+	u64 vruntime = cfs_rq->min_vruntime;
+
+	/*
+	 * The 'current' period is already promised to the current tasks,
+	 * however the extra weight of the new task will slow them down a
+	 * little, place the new task so that it fits in the slot that
+	 * stays open at the end.
+	 */
+	if (initial && sched_feat(START_DEBIT))
+		vruntime += sched_vslice(cfs_rq, se);
+
+	/* sleeps up to a single latency don't count. */
+	if (!initial) {
+		unsigned long thresh = sysctl_sched_latency;
+
+		/*
+		 * Halve their sleep time's effect, to allow
+		 * for a gentler effect of sleepers:
+		 */
+		if (sched_feat(GENTLE_FAIR_SLEEPERS))
+			thresh >>= 1;
+
+		vruntime -= thresh;
+	}
+
+	/* ensure we never gain time by being placed backwards. */
+	vruntime = max_vruntime(se->vruntime, vruntime);
+
+	se->vruntime = vruntime;
+}
+
+static void check_enqueue_throttle(struct cfs_rq *cfs_rq);
+
+static void
+enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
+{
+	/*
+	 * Update the normalized vruntime before updating min_vruntime
+	 * through callig update_curr().
+	 */
+	if (!(flags & ENQUEUE_WAKEUP) || (flags & ENQUEUE_WAKING))
+		se->vruntime += cfs_rq->min_vruntime;
+
+	/*
+	 * Update run-time statistics of the 'current'.
+	 */
+	update_curr(cfs_rq);
+	update_cfs_load(cfs_rq, 0);
+	account_entity_enqueue(cfs_rq, se);
+	update_cfs_shares(cfs_rq);
+
+	if (flags & ENQUEUE_WAKEUP) {
+		place_entity(cfs_rq, se, 0);
+		enqueue_sleeper(cfs_rq, se);
+	}
+
+	update_stats_enqueue(cfs_rq, se);
+	check_spread(cfs_rq, se);
+	if (se != cfs_rq->curr)
+		__enqueue_entity(cfs_rq, se);
+	se->on_rq = 1;
+
+	if (cfs_rq->nr_running == 1) {
+		list_add_leaf_cfs_rq(cfs_rq);
+		check_enqueue_throttle(cfs_rq);
+	}
+}
+
+static void __clear_buddies_last(struct sched_entity *se)
+{
+	for_each_sched_entity(se) {
+		struct cfs_rq *cfs_rq = cfs_rq_of(se);
+		if (cfs_rq->last == se)
+			cfs_rq->last = NULL;
+		else
+			break;
+	}
+}
+
+static void __clear_buddies_next(struct sched_entity *se)
+{
+	for_each_sched_entity(se) {
+		struct cfs_rq *cfs_rq = cfs_rq_of(se);
+		if (cfs_rq->next == se)
+			cfs_rq->next = NULL;
+		else
+			break;
+	}
+}
+
+static void __clear_buddies_skip(struct sched_entity *se)
+{
+	for_each_sched_entity(se) {
+		struct cfs_rq *cfs_rq = cfs_rq_of(se);
+		if (cfs_rq->skip == se)
+			cfs_rq->skip = NULL;
+		else
+			break;
+	}
+}
+
+static void clear_buddies(struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
+	if (cfs_rq->last == se)
+		__clear_buddies_last(se);
+
+	if (cfs_rq->next == se)
+		__clear_buddies_next(se);
+
+	if (cfs_rq->skip == se)
+		__clear_buddies_skip(se);
+}
+
+static void return_cfs_rq_runtime(struct cfs_rq *cfs_rq);
+
+static void
+dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
+{
+	/*
+	 * Update run-time statistics of the 'current'.
+	 */
+	update_curr(cfs_rq);
+
+	update_stats_dequeue(cfs_rq, se);
+	if (flags & DEQUEUE_SLEEP) {
+#ifdef CONFIG_SCHEDSTATS
+		if (entity_is_task(se)) {
+			struct task_struct *tsk = task_of(se);
+
+			if (tsk->state & TASK_INTERRUPTIBLE)
+				se->statistics.sleep_start = rq_of(cfs_rq)->clock;
+			if (tsk->state & TASK_UNINTERRUPTIBLE)
+				se->statistics.block_start = rq_of(cfs_rq)->clock;
+		}
+#endif
+	}
+
+	clear_buddies(cfs_rq, se);
+
+	if (se != cfs_rq->curr)
+		__dequeue_entity(cfs_rq, se);
+	se->on_rq = 0;
+	update_cfs_load(cfs_rq, 0);
+	account_entity_dequeue(cfs_rq, se);
+
+	/*
+	 * Normalize the entity after updating the min_vruntime because the
+	 * update can refer to the ->curr item and we need to reflect this
+	 * movement in our normalized position.
+	 */
+	if (!(flags & DEQUEUE_SLEEP))
+		se->vruntime -= cfs_rq->min_vruntime;
+
+	/* return excess runtime on last dequeue */
+	return_cfs_rq_runtime(cfs_rq);
+
+	update_min_vruntime(cfs_rq);
+	update_cfs_shares(cfs_rq);
+}
+
+/*
+ * Preempt the current task with a newly woken task if needed:
+ */
+static void
+check_preempt_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr)
+{
+	unsigned long ideal_runtime, delta_exec;
+	struct sched_entity *se;
+	s64 delta;
+
+	ideal_runtime = sched_slice(cfs_rq, curr);
+	delta_exec = curr->sum_exec_runtime - curr->prev_sum_exec_runtime;
+	if (delta_exec > ideal_runtime) {
+		resched_task(rq_of(cfs_rq)->curr);
+		/*
+		 * The current task ran long enough, ensure it doesn't get
+		 * re-elected due to buddy favours.
+		 */
+		clear_buddies(cfs_rq, curr);
+		return;
+	}
+
+	/*
+	 * Ensure that a task that missed wakeup preemption by a
+	 * narrow margin doesn't have to wait for a full slice.
+	 * This also mitigates buddy induced latencies under load.
+	 */
+	if (delta_exec < sysctl_sched_min_granularity)
+		return;
+
+	se = __pick_first_entity(cfs_rq);
+	delta = curr->vruntime - se->vruntime;
+
+	if (delta < 0)
+		return;
+
+	if (delta > ideal_runtime)
+		resched_task(rq_of(cfs_rq)->curr);
+}
+
+static void
+set_next_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
+	/* 'current' is not kept within the tree. */
+	if (se->on_rq) {
+		/*
+		 * Any task has to be enqueued before it get to execute on
+		 * a CPU. So account for the time it spent waiting on the
+		 * runqueue.
+		 */
+		update_stats_wait_end(cfs_rq, se);
+		__dequeue_entity(cfs_rq, se);
+	}
+
+	update_stats_curr_start(cfs_rq, se);
+	cfs_rq->curr = se;
+#ifdef CONFIG_SCHEDSTATS
+	/*
+	 * Track our maximum slice length, if the CPU's load is at
+	 * least twice that of our own weight (i.e. dont track it
+	 * when there are only lesser-weight tasks around):
+	 */
+	if (rq_of(cfs_rq)->load.weight >= 2*se->load.weight) {
+		se->statistics.slice_max = max(se->statistics.slice_max,
+			se->sum_exec_runtime - se->prev_sum_exec_runtime);
+	}
+#endif
+	se->prev_sum_exec_runtime = se->sum_exec_runtime;
+}
+
+static int
+wakeup_preempt_entity(struct sched_entity *curr, struct sched_entity *se);
+
+/*
+ * Pick the next process, keeping these things in mind, in this order:
+ * 1) keep things fair between processes/task groups
+ * 2) pick the "next" process, since someone really wants that to run
+ * 3) pick the "last" process, for cache locality
+ * 4) do not run the "skip" process, if something else is available
+ */
+static struct sched_entity *pick_next_entity(struct cfs_rq *cfs_rq)
+{
+	struct sched_entity *se = __pick_first_entity(cfs_rq);
+	struct sched_entity *left = se;
+
+	/*
+	 * Avoid running the skip buddy, if running something else can
+	 * be done without getting too unfair.
+	 */
+	if (cfs_rq->skip == se) {
+		struct sched_entity *second = __pick_next_entity(se);
+		if (second && wakeup_preempt_entity(second, left) < 1)
+			se = second;
+	}
+
+	/*
+	 * Prefer last buddy, try to return the CPU to a preempted task.
+	 */
+	if (cfs_rq->last && wakeup_preempt_entity(cfs_rq->last, left) < 1)
+		se = cfs_rq->last;
+
+	/*
+	 * Someone really wants this to run. If it's not unfair, run it.
+	 */
+	if (cfs_rq->next && wakeup_preempt_entity(cfs_rq->next, left) < 1)
+		se = cfs_rq->next;
+
+	clear_buddies(cfs_rq, se);
+
+	return se;
+}
+
+static void check_cfs_rq_runtime(struct cfs_rq *cfs_rq);
+
+static void put_prev_entity(struct cfs_rq *cfs_rq, struct sched_entity *prev)
+{
+	/*
+	 * If still on the runqueue then deactivate_task()
+	 * was not called and update_curr() has to be done:
+	 */
+	if (prev->on_rq)
+		update_curr(cfs_rq);
+
+	/* throttle cfs_rqs exceeding runtime */
+	check_cfs_rq_runtime(cfs_rq);
+
+	check_spread(cfs_rq, prev);
+	if (prev->on_rq) {
+		update_stats_wait_start(cfs_rq, prev);
+		/* Put 'current' back into the tree. */
+		__enqueue_entity(cfs_rq, prev);
+	}
+	cfs_rq->curr = NULL;
+}
+
+static void
+entity_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr, int queued)
+{
+	/*
+	 * Update run-time statistics of the 'current'.
+	 */
+	update_curr(cfs_rq);
+
+	/*
+	 * Update share accounting for long-running entities.
+	 */
+	update_entity_shares_tick(cfs_rq);
+
+#ifdef CONFIG_SCHED_HRTICK
+	/*
+	 * queued ticks are scheduled to match the slice, so don't bother
+	 * validating it and just reschedule.
+	 */
+	if (queued) {
+		resched_task(rq_of(cfs_rq)->curr);
+		return;
+	}
+	/*
+	 * don't let the period tick interfere with the hrtick preemption
+	 */
+	if (!sched_feat(DOUBLE_TICK) &&
+			hrtimer_active(&rq_of(cfs_rq)->hrtick_timer))
+		return;
+#endif
+
+	if (cfs_rq->nr_running > 1)
+		check_preempt_tick(cfs_rq, curr);
+}
+
+
+/**************************************************
+ * CFS bandwidth control machinery
+ */
+
+#ifdef CONFIG_CFS_BANDWIDTH
+
+#ifdef HAVE_JUMP_LABEL
+static struct jump_label_key __cfs_bandwidth_used;
+
+static inline bool cfs_bandwidth_used(void)
+{
+	return static_branch(&__cfs_bandwidth_used);
+}
+
+void account_cfs_bandwidth_used(int enabled, int was_enabled)
+{
+	/* only need to count groups transitioning between enabled/!enabled */
+	if (enabled && !was_enabled)
+		jump_label_inc(&__cfs_bandwidth_used);
+	else if (!enabled && was_enabled)
+		jump_label_dec(&__cfs_bandwidth_used);
+}
+#else /* HAVE_JUMP_LABEL */
+static bool cfs_bandwidth_used(void)
+{
+	return true;
+}
+
+void account_cfs_bandwidth_used(int enabled, int was_enabled) {}
+#endif /* HAVE_JUMP_LABEL */
+
+/*
+ * default period for cfs group bandwidth.
+ * default: 0.1s, units: nanoseconds
+ */
+static inline u64 default_cfs_period(void)
+{
+	return 100000000ULL;
+}
+
+static inline u64 sched_cfs_bandwidth_slice(void)
+{
+	return (u64)sysctl_sched_cfs_bandwidth_slice * NSEC_PER_USEC;
+}
+
+/*
+ * Replenish runtime according to assigned quota and update expiration time.
+ * We use sched_clock_cpu directly instead of rq->clock to avoid adding
+ * additional synchronization around rq->lock.
+ *
+ * requires cfs_b->lock
+ */
+void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b)
+{
+	u64 now;
+
+	if (cfs_b->quota == RUNTIME_INF)
+		return;
+
+	now = sched_clock_cpu(smp_processor_id());
+	cfs_b->runtime = cfs_b->quota;
+	cfs_b->runtime_expires = now + ktime_to_ns(cfs_b->period);
+}
+
+static inline struct cfs_bandwidth *tg_cfs_bandwidth(struct task_group *tg)
+{
+	return &tg->cfs_bandwidth;
+}
+
+/* returns 0 on failure to allocate runtime */
+static int assign_cfs_rq_runtime(struct cfs_rq *cfs_rq)
+{
+	struct task_group *tg = cfs_rq->tg;
+	struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(tg);
+	u64 amount = 0, min_amount, expires;
+
+	/* note: this is a positive sum as runtime_remaining <= 0 */
+	min_amount = sched_cfs_bandwidth_slice() - cfs_rq->runtime_remaining;
+
+	raw_spin_lock(&cfs_b->lock);
+	if (cfs_b->quota == RUNTIME_INF)
+		amount = min_amount;
+	else {
+		/*
+		 * If the bandwidth pool has become inactive, then at least one
+		 * period must have elapsed since the last consumption.
+		 * Refresh the global state and ensure bandwidth timer becomes
+		 * active.
+		 */
+		if (!cfs_b->timer_active) {
+			__refill_cfs_bandwidth_runtime(cfs_b);
+			__start_cfs_bandwidth(cfs_b);
+		}
+
+		if (cfs_b->runtime > 0) {
+			amount = min(cfs_b->runtime, min_amount);
+			cfs_b->runtime -= amount;
+			cfs_b->idle = 0;
+		}
+	}
+	expires = cfs_b->runtime_expires;
+	raw_spin_unlock(&cfs_b->lock);
+
+	cfs_rq->runtime_remaining += amount;
+	/*
+	 * we may have advanced our local expiration to account for allowed
+	 * spread between our sched_clock and the one on which runtime was
+	 * issued.
+	 */
+	if ((s64)(expires - cfs_rq->runtime_expires) > 0)
+		cfs_rq->runtime_expires = expires;
+
+	return cfs_rq->runtime_remaining > 0;
+}
+
+/*
+ * Note: This depends on the synchronization provided by sched_clock and the
+ * fact that rq->clock snapshots this value.
+ */
+static void expire_cfs_rq_runtime(struct cfs_rq *cfs_rq)
+{
+	struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(cfs_rq->tg);
+	struct rq *rq = rq_of(cfs_rq);
+
+	/* if the deadline is ahead of our clock, nothing to do */
+	if (likely((s64)(rq->clock - cfs_rq->runtime_expires) < 0))
+		return;
+
+	if (cfs_rq->runtime_remaining < 0)
+		return;
+
+	/*
+	 * If the local deadline has passed we have to consider the
+	 * possibility that our sched_clock is 'fast' and the global deadline
+	 * has not truly expired.
+	 *
+	 * Fortunately we can check determine whether this the case by checking
+	 * whether the global deadline has advanced.
+	 */
+
+	if ((s64)(cfs_rq->runtime_expires - cfs_b->runtime_expires) >= 0) {
+		/* extend local deadline, drift is bounded above by 2 ticks */
+		cfs_rq->runtime_expires += TICK_NSEC;
+	} else {
+		/* global deadline is ahead, expiration has passed */
+		cfs_rq->runtime_remaining = 0;
+	}
+}
+
+static void __account_cfs_rq_runtime(struct cfs_rq *cfs_rq,
+				     unsigned long delta_exec)
+{
+	/* dock delta_exec before expiring quota (as it could span periods) */
+	cfs_rq->runtime_remaining -= delta_exec;
+	expire_cfs_rq_runtime(cfs_rq);
+
+	if (likely(cfs_rq->runtime_remaining > 0))
+		return;
+
+	/*
+	 * if we're unable to extend our runtime we resched so that the active
+	 * hierarchy can be throttled
+	 */
+	if (!assign_cfs_rq_runtime(cfs_rq) && likely(cfs_rq->curr))
+		resched_task(rq_of(cfs_rq)->curr);
+}
+
+static __always_inline void account_cfs_rq_runtime(struct cfs_rq *cfs_rq,
+						   unsigned long delta_exec)
+{
+	if (!cfs_bandwidth_used() || !cfs_rq->runtime_enabled)
+		return;
+
+	__account_cfs_rq_runtime(cfs_rq, delta_exec);
+}
+
+static inline int cfs_rq_throttled(struct cfs_rq *cfs_rq)
+{
+	return cfs_bandwidth_used() && cfs_rq->throttled;
+}
+
+/* check whether cfs_rq, or any parent, is throttled */
+static inline int throttled_hierarchy(struct cfs_rq *cfs_rq)
+{
+	return cfs_bandwidth_used() && cfs_rq->throttle_count;
+}
+
+/*
+ * Ensure that neither of the group entities corresponding to src_cpu or
+ * dest_cpu are members of a throttled hierarchy when performing group
+ * load-balance operations.
+ */
+static inline int throttled_lb_pair(struct task_group *tg,
+				    int src_cpu, int dest_cpu)
+{
+	struct cfs_rq *src_cfs_rq, *dest_cfs_rq;
+
+	src_cfs_rq = tg->cfs_rq[src_cpu];
+	dest_cfs_rq = tg->cfs_rq[dest_cpu];
+
+	return throttled_hierarchy(src_cfs_rq) ||
+	       throttled_hierarchy(dest_cfs_rq);
+}
+
+/* updated child weight may affect parent so we have to do this bottom up */
+static int tg_unthrottle_up(struct task_group *tg, void *data)
+{
+	struct rq *rq = data;
+	struct cfs_rq *cfs_rq = tg->cfs_rq[cpu_of(rq)];
+
+	cfs_rq->throttle_count--;
+#ifdef CONFIG_SMP
+	if (!cfs_rq->throttle_count) {
+		u64 delta = rq->clock_task - cfs_rq->load_stamp;
+
+		/* leaving throttled state, advance shares averaging windows */
+		cfs_rq->load_stamp += delta;
+		cfs_rq->load_last += delta;
+
+		/* update entity weight now that we are on_rq again */
+		update_cfs_shares(cfs_rq);
+	}
+#endif
+
+	return 0;
+}
+
+static int tg_throttle_down(struct task_group *tg, void *data)
+{
+	struct rq *rq = data;
+	struct cfs_rq *cfs_rq = tg->cfs_rq[cpu_of(rq)];
+
+	/* group is entering throttled state, record last load */
+	if (!cfs_rq->throttle_count)
+		update_cfs_load(cfs_rq, 0);
+	cfs_rq->throttle_count++;
+
+	return 0;
+}
+
+static void throttle_cfs_rq(struct cfs_rq *cfs_rq)
+{
+	struct rq *rq = rq_of(cfs_rq);
+	struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(cfs_rq->tg);
+	struct sched_entity *se;
+	long task_delta, dequeue = 1;
+
+	se = cfs_rq->tg->se[cpu_of(rq_of(cfs_rq))];
+
+	/* account load preceding throttle */
+	rcu_read_lock();
+	walk_tg_tree_from(cfs_rq->tg, tg_throttle_down, tg_nop, (void *)rq);
+	rcu_read_unlock();
+
+	task_delta = cfs_rq->h_nr_running;
+	for_each_sched_entity(se) {
+		struct cfs_rq *qcfs_rq = cfs_rq_of(se);
+		/* throttled entity or throttle-on-deactivate */
+		if (!se->on_rq)
+			break;
+
+		if (dequeue)
+			dequeue_entity(qcfs_rq, se, DEQUEUE_SLEEP);
+		qcfs_rq->h_nr_running -= task_delta;
+
+		if (qcfs_rq->load.weight)
+			dequeue = 0;
+	}
+
+	if (!se)
+		rq->nr_running -= task_delta;
+
+	cfs_rq->throttled = 1;
+	cfs_rq->throttled_timestamp = rq->clock;
+	raw_spin_lock(&cfs_b->lock);
+	list_add_tail_rcu(&cfs_rq->throttled_list, &cfs_b->throttled_cfs_rq);
+	raw_spin_unlock(&cfs_b->lock);
+}
+
+void unthrottle_cfs_rq(struct cfs_rq *cfs_rq)
+{
+	struct rq *rq = rq_of(cfs_rq);
+	struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(cfs_rq->tg);
+	struct sched_entity *se;
+	int enqueue = 1;
+	long task_delta;
+
+	se = cfs_rq->tg->se[cpu_of(rq_of(cfs_rq))];
+
+	cfs_rq->throttled = 0;
+	raw_spin_lock(&cfs_b->lock);
+	cfs_b->throttled_time += rq->clock - cfs_rq->throttled_timestamp;
+	list_del_rcu(&cfs_rq->throttled_list);
+	raw_spin_unlock(&cfs_b->lock);
+	cfs_rq->throttled_timestamp = 0;
+
+	update_rq_clock(rq);
+	/* update hierarchical throttle state */
+	walk_tg_tree_from(cfs_rq->tg, tg_nop, tg_unthrottle_up, (void *)rq);
+
+	if (!cfs_rq->load.weight)
+		return;
+
+	task_delta = cfs_rq->h_nr_running;
+	for_each_sched_entity(se) {
+		if (se->on_rq)
+			enqueue = 0;
+
+		cfs_rq = cfs_rq_of(se);
+		if (enqueue)
+			enqueue_entity(cfs_rq, se, ENQUEUE_WAKEUP);
+		cfs_rq->h_nr_running += task_delta;
+
+		if (cfs_rq_throttled(cfs_rq))
+			break;
+	}
+
+	if (!se)
+		rq->nr_running += task_delta;
+
+	/* determine whether we need to wake up potentially idle cpu */
+	if (rq->curr == rq->idle && rq->cfs.nr_running)
+		resched_task(rq->curr);
+}
+
+static u64 distribute_cfs_runtime(struct cfs_bandwidth *cfs_b,
+		u64 remaining, u64 expires)
+{
+	struct cfs_rq *cfs_rq;
+	u64 runtime = remaining;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(cfs_rq, &cfs_b->throttled_cfs_rq,
+				throttled_list) {
+		struct rq *rq = rq_of(cfs_rq);
+
+		raw_spin_lock(&rq->lock);
+		if (!cfs_rq_throttled(cfs_rq))
+			goto next;
+
+		runtime = -cfs_rq->runtime_remaining + 1;
+		if (runtime > remaining)
+			runtime = remaining;
+		remaining -= runtime;
+
+		cfs_rq->runtime_remaining += runtime;
+		cfs_rq->runtime_expires = expires;
+
+		/* we check whether we're throttled above */
+		if (cfs_rq->runtime_remaining > 0)
+			unthrottle_cfs_rq(cfs_rq);
+
+next:
+		raw_spin_unlock(&rq->lock);
+
+		if (!remaining)
+			break;
+	}
+	rcu_read_unlock();
+
+	return remaining;
+}
+
+/*
+ * Responsible for refilling a task_group's bandwidth and unthrottling its
+ * cfs_rqs as appropriate. If there has been no activity within the last
+ * period the timer is deactivated until scheduling resumes; cfs_b->idle is
+ * used to track this state.
+ */
+static int do_sched_cfs_period_timer(struct cfs_bandwidth *cfs_b, int overrun)
+{
+	u64 runtime, runtime_expires;
+	int idle = 1, throttled;
+
+	raw_spin_lock(&cfs_b->lock);
+	/* no need to continue the timer with no bandwidth constraint */
+	if (cfs_b->quota == RUNTIME_INF)
+		goto out_unlock;
+
+	throttled = !list_empty(&cfs_b->throttled_cfs_rq);
+	/* idle depends on !throttled (for the case of a large deficit) */
+	idle = cfs_b->idle && !throttled;
+	cfs_b->nr_periods += overrun;
+
+	/* if we're going inactive then everything else can be deferred */
+	if (idle)
+		goto out_unlock;
+
+	__refill_cfs_bandwidth_runtime(cfs_b);
+
+	if (!throttled) {
+		/* mark as potentially idle for the upcoming period */
+		cfs_b->idle = 1;
+		goto out_unlock;
+	}
+
+	/* account preceding periods in which throttling occurred */
+	cfs_b->nr_throttled += overrun;
+
+	/*
+	 * There are throttled entities so we must first use the new bandwidth
+	 * to unthrottle them before making it generally available.  This
+	 * ensures that all existing debts will be paid before a new cfs_rq is
+	 * allowed to run.
+	 */
+	runtime = cfs_b->runtime;
+	runtime_expires = cfs_b->runtime_expires;
+	cfs_b->runtime = 0;
+
+	/*
+	 * This check is repeated as we are holding onto the new bandwidth
+	 * while we unthrottle.  This can potentially race with an unthrottled
+	 * group trying to acquire new bandwidth from the global pool.
+	 */
+	while (throttled && runtime > 0) {
+		raw_spin_unlock(&cfs_b->lock);
+		/* we can't nest cfs_b->lock while distributing bandwidth */
+		runtime = distribute_cfs_runtime(cfs_b, runtime,
+						 runtime_expires);
+		raw_spin_lock(&cfs_b->lock);
+
+		throttled = !list_empty(&cfs_b->throttled_cfs_rq);
+	}
+
+	/* return (any) remaining runtime */
+	cfs_b->runtime = runtime;
+	/*
+	 * While we are ensured activity in the period following an
+	 * unthrottle, this also covers the case in which the new bandwidth is
+	 * insufficient to cover the existing bandwidth deficit.  (Forcing the
+	 * timer to remain active while there are any throttled entities.)
+	 */
+	cfs_b->idle = 0;
+out_unlock:
+	if (idle)
+		cfs_b->timer_active = 0;
+	raw_spin_unlock(&cfs_b->lock);
+
+	return idle;
+}
+
+/* a cfs_rq won't donate quota below this amount */
+static const u64 min_cfs_rq_runtime = 1 * NSEC_PER_MSEC;
+/* minimum remaining period time to redistribute slack quota */
+static const u64 min_bandwidth_expiration = 2 * NSEC_PER_MSEC;
+/* how long we wait to gather additional slack before distributing */
+static const u64 cfs_bandwidth_slack_period = 5 * NSEC_PER_MSEC;
+
+/* are we near the end of the current quota period? */
+static int runtime_refresh_within(struct cfs_bandwidth *cfs_b, u64 min_expire)
+{
+	struct hrtimer *refresh_timer = &cfs_b->period_timer;
+	u64 remaining;
+
+	/* if the call-back is running a quota refresh is already occurring */
+	if (hrtimer_callback_running(refresh_timer))
+		return 1;
+
+	/* is a quota refresh about to occur? */
+	remaining = ktime_to_ns(hrtimer_expires_remaining(refresh_timer));
+	if (remaining < min_expire)
+		return 1;
+
+	return 0;
+}
+
+static void start_cfs_slack_bandwidth(struct cfs_bandwidth *cfs_b)
+{
+	u64 min_left = cfs_bandwidth_slack_period + min_bandwidth_expiration;
+
+	/* if there's a quota refresh soon don't bother with slack */
+	if (runtime_refresh_within(cfs_b, min_left))
+		return;
+
+	start_bandwidth_timer(&cfs_b->slack_timer,
+				ns_to_ktime(cfs_bandwidth_slack_period));
+}
+
+/* we know any runtime found here is valid as update_curr() precedes return */
+static void __return_cfs_rq_runtime(struct cfs_rq *cfs_rq)
+{
+	struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(cfs_rq->tg);
+	s64 slack_runtime = cfs_rq->runtime_remaining - min_cfs_rq_runtime;
+
+	if (slack_runtime <= 0)
+		return;
+
+	raw_spin_lock(&cfs_b->lock);
+	if (cfs_b->quota != RUNTIME_INF &&
+	    cfs_rq->runtime_expires == cfs_b->runtime_expires) {
+		cfs_b->runtime += slack_runtime;
+
+		/* we are under rq->lock, defer unthrottling using a timer */
+		if (cfs_b->runtime > sched_cfs_bandwidth_slice() &&
+		    !list_empty(&cfs_b->throttled_cfs_rq))
+			start_cfs_slack_bandwidth(cfs_b);
+	}
+	raw_spin_unlock(&cfs_b->lock);
+
+	/* even if it's not valid for return we don't want to try again */
+	cfs_rq->runtime_remaining -= slack_runtime;
+}
+
+static __always_inline void return_cfs_rq_runtime(struct cfs_rq *cfs_rq)
+{
+	if (!cfs_bandwidth_used())
+		return;
+
+	if (!cfs_rq->runtime_enabled || cfs_rq->nr_running)
+		return;
+
+	__return_cfs_rq_runtime(cfs_rq);
+}
+
+/*
+ * This is done with a timer (instead of inline with bandwidth return) since
+ * it's necessary to juggle rq->locks to unthrottle their respective cfs_rqs.
+ */
+static void do_sched_cfs_slack_timer(struct cfs_bandwidth *cfs_b)
+{
+	u64 runtime = 0, slice = sched_cfs_bandwidth_slice();
+	u64 expires;
+
+	/* confirm we're still not at a refresh boundary */
+	if (runtime_refresh_within(cfs_b, min_bandwidth_expiration))
+		return;
+
+	raw_spin_lock(&cfs_b->lock);
+	if (cfs_b->quota != RUNTIME_INF && cfs_b->runtime > slice) {
+		runtime = cfs_b->runtime;
+		cfs_b->runtime = 0;
+	}
+	expires = cfs_b->runtime_expires;
+	raw_spin_unlock(&cfs_b->lock);
+
+	if (!runtime)
+		return;
+
+	runtime = distribute_cfs_runtime(cfs_b, runtime, expires);
+
+	raw_spin_lock(&cfs_b->lock);
+	if (expires == cfs_b->runtime_expires)
+		cfs_b->runtime = runtime;
+	raw_spin_unlock(&cfs_b->lock);
+}
+
+/*
+ * When a group wakes up we want to make sure that its quota is not already
+ * expired/exceeded, otherwise it may be allowed to steal additional ticks of
+ * runtime as update_curr() throttling can not not trigger until it's on-rq.
+ */
+static void check_enqueue_throttle(struct cfs_rq *cfs_rq)
+{
+	if (!cfs_bandwidth_used())
+		return;
+
+	/* an active group must be handled by the update_curr()->put() path */
+	if (!cfs_rq->runtime_enabled || cfs_rq->curr)
+		return;
+
+	/* ensure the group is not already throttled */
+	if (cfs_rq_throttled(cfs_rq))
+		return;
+
+	/* update runtime allocation */
+	account_cfs_rq_runtime(cfs_rq, 0);
+	if (cfs_rq->runtime_remaining <= 0)
+		throttle_cfs_rq(cfs_rq);
+}
+
+/* conditionally throttle active cfs_rq's from put_prev_entity() */
+static void check_cfs_rq_runtime(struct cfs_rq *cfs_rq)
+{
+	if (!cfs_bandwidth_used())
+		return;
+
+	if (likely(!cfs_rq->runtime_enabled || cfs_rq->runtime_remaining > 0))
+		return;
+
+	/*
+	 * it's possible for a throttled entity to be forced into a running
+	 * state (e.g. set_curr_task), in this case we're finished.
+	 */
+	if (cfs_rq_throttled(cfs_rq))
+		return;
+
+	throttle_cfs_rq(cfs_rq);
+}
+
+static inline u64 default_cfs_period(void);
+static int do_sched_cfs_period_timer(struct cfs_bandwidth *cfs_b, int overrun);
+static void do_sched_cfs_slack_timer(struct cfs_bandwidth *cfs_b);
+
+static enum hrtimer_restart sched_cfs_slack_timer(struct hrtimer *timer)
+{
+	struct cfs_bandwidth *cfs_b =
+		container_of(timer, struct cfs_bandwidth, slack_timer);
+	do_sched_cfs_slack_timer(cfs_b);
+
+	return HRTIMER_NORESTART;
+}
+
+static enum hrtimer_restart sched_cfs_period_timer(struct hrtimer *timer)
+{
+	struct cfs_bandwidth *cfs_b =
+		container_of(timer, struct cfs_bandwidth, period_timer);
+	ktime_t now;
+	int overrun;
+	int idle = 0;
+
+	for (;;) {
+		now = hrtimer_cb_get_time(timer);
+		overrun = hrtimer_forward(timer, now, cfs_b->period);
+
+		if (!overrun)
+			break;
+
+		idle = do_sched_cfs_period_timer(cfs_b, overrun);
+	}
+
+	return idle ? HRTIMER_NORESTART : HRTIMER_RESTART;
+}
+
+void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b)
+{
+	raw_spin_lock_init(&cfs_b->lock);
+	cfs_b->runtime = 0;
+	cfs_b->quota = RUNTIME_INF;
+	cfs_b->period = ns_to_ktime(default_cfs_period());
+
+	INIT_LIST_HEAD(&cfs_b->throttled_cfs_rq);
+	hrtimer_init(&cfs_b->period_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	cfs_b->period_timer.function = sched_cfs_period_timer;
+	hrtimer_init(&cfs_b->slack_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	cfs_b->slack_timer.function = sched_cfs_slack_timer;
+}
+
+static void init_cfs_rq_runtime(struct cfs_rq *cfs_rq)
+{
+	cfs_rq->runtime_enabled = 0;
+	INIT_LIST_HEAD(&cfs_rq->throttled_list);
+}
+
+/* requires cfs_b->lock, may release to reprogram timer */
+void __start_cfs_bandwidth(struct cfs_bandwidth *cfs_b)
+{
+	/*
+	 * The timer may be active because we're trying to set a new bandwidth
+	 * period or because we're racing with the tear-down path
+	 * (timer_active==0 becomes visible before the hrtimer call-back
+	 * terminates).  In either case we ensure that it's re-programmed
+	 */
+	while (unlikely(hrtimer_active(&cfs_b->period_timer))) {
+		raw_spin_unlock(&cfs_b->lock);
+		/* ensure cfs_b->lock is available while we wait */
+		hrtimer_cancel(&cfs_b->period_timer);
+
+		raw_spin_lock(&cfs_b->lock);
+		/* if someone else restarted the timer then we're done */
+		if (cfs_b->timer_active)
+			return;
+	}
+
+	cfs_b->timer_active = 1;
+	start_bandwidth_timer(&cfs_b->period_timer, cfs_b->period);
+}
+
+static void destroy_cfs_bandwidth(struct cfs_bandwidth *cfs_b)
+{
+	hrtimer_cancel(&cfs_b->period_timer);
+	hrtimer_cancel(&cfs_b->slack_timer);
+}
+
+void unthrottle_offline_cfs_rqs(struct rq *rq)
+{
+	struct cfs_rq *cfs_rq;
+
+	for_each_leaf_cfs_rq(rq, cfs_rq) {
+		struct cfs_bandwidth *cfs_b = tg_cfs_bandwidth(cfs_rq->tg);
+
+		if (!cfs_rq->runtime_enabled)
+			continue;
+
+		/*
+		 * clock_task is not advancing so we just need to make sure
+		 * there's some valid quota amount
+		 */
+		cfs_rq->runtime_remaining = cfs_b->quota;
+		if (cfs_rq_throttled(cfs_rq))
+			unthrottle_cfs_rq(cfs_rq);
+	}
+}
+
+#else /* CONFIG_CFS_BANDWIDTH */
+static void account_cfs_rq_runtime(struct cfs_rq *cfs_rq,
+				     unsigned long delta_exec) {}
+static void check_cfs_rq_runtime(struct cfs_rq *cfs_rq) {}
+static void check_enqueue_throttle(struct cfs_rq *cfs_rq) {}
+static void return_cfs_rq_runtime(struct cfs_rq *cfs_rq) {}
+
+static inline int cfs_rq_throttled(struct cfs_rq *cfs_rq)
+{
+	return 0;
+}
+
+static inline int throttled_hierarchy(struct cfs_rq *cfs_rq)
+{
+	return 0;
+}
+
+static inline int throttled_lb_pair(struct task_group *tg,
+				    int src_cpu, int dest_cpu)
+{
+	return 0;
+}
+
+void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b) {}
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+static void init_cfs_rq_runtime(struct cfs_rq *cfs_rq) {}
+#endif
+
+static inline struct cfs_bandwidth *tg_cfs_bandwidth(struct task_group *tg)
+{
+	return NULL;
+}
+static inline void destroy_cfs_bandwidth(struct cfs_bandwidth *cfs_b) {}
+void unthrottle_offline_cfs_rqs(struct rq *rq) {}
+
+#endif /* CONFIG_CFS_BANDWIDTH */
+
+/**************************************************
+ * CFS operations on tasks:
+ */
+
+#ifdef CONFIG_SCHED_HRTICK
+static void hrtick_start_fair(struct rq *rq, struct task_struct *p)
+{
+	struct sched_entity *se = &p->se;
+	struct cfs_rq *cfs_rq = cfs_rq_of(se);
+
+	WARN_ON(task_rq(p) != rq);
+
+	if (cfs_rq->nr_running > 1) {
+		u64 slice = sched_slice(cfs_rq, se);
+		u64 ran = se->sum_exec_runtime - se->prev_sum_exec_runtime;
+		s64 delta = slice - ran;
+
+		if (delta < 0) {
+			if (rq->curr == p)
+				resched_task(p);
+			return;
+		}
+
+		/*
+		 * Don't schedule slices shorter than 10000ns, that just
+		 * doesn't make sense. Rely on vruntime for fairness.
+		 */
+		if (rq->curr != p)
+			delta = max_t(s64, 10000LL, delta);
+
+		hrtick_start(rq, delta);
+	}
+}
+
+/*
+ * called from enqueue/dequeue and updates the hrtick when the
+ * current task is from our class and nr_running is low enough
+ * to matter.
+ */
+static void hrtick_update(struct rq *rq)
+{
+	struct task_struct *curr = rq->curr;
+
+	if (!hrtick_enabled(rq) || curr->sched_class != &fair_sched_class)
+		return;
+
+	if (cfs_rq_of(&curr->se)->nr_running < sched_nr_latency)
+		hrtick_start_fair(rq, curr);
+}
+#else /* !CONFIG_SCHED_HRTICK */
+static inline void
+hrtick_start_fair(struct rq *rq, struct task_struct *p)
+{
+}
+
+static inline void hrtick_update(struct rq *rq)
+{
+}
+#endif
+
+/*
+ * The enqueue_task method is called before nr_running is
+ * increased. Here we update the fair scheduling stats and
+ * then put the task into the rbtree:
+ */
+static void
+enqueue_task_fair(struct rq *rq, struct task_struct *p, int flags)
+{
+	struct cfs_rq *cfs_rq;
+	struct sched_entity *se = &p->se;
+
+	for_each_sched_entity(se) {
+		if (se->on_rq)
+			break;
+		cfs_rq = cfs_rq_of(se);
+		enqueue_entity(cfs_rq, se, flags);
+
+		/*
+		 * end evaluation on encountering a throttled cfs_rq
+		 *
+		 * note: in the case of encountering a throttled cfs_rq we will
+		 * post the final h_nr_running increment below.
+		*/
+		if (cfs_rq_throttled(cfs_rq))
+			break;
+		cfs_rq->h_nr_running++;
+
+		flags = ENQUEUE_WAKEUP;
+	}
+
+	for_each_sched_entity(se) {
+		cfs_rq = cfs_rq_of(se);
+		cfs_rq->h_nr_running++;
+
+		if (cfs_rq_throttled(cfs_rq))
+			break;
+
+		update_cfs_load(cfs_rq, 0);
+		update_cfs_shares(cfs_rq);
+	}
+
+	if (!se)
+		inc_nr_running(rq);
+	hrtick_update(rq);
+}
+
+static void set_next_buddy(struct sched_entity *se);
+
+/*
+ * The dequeue_task method is called before nr_running is
+ * decreased. We remove the task from the rbtree and
+ * update the fair scheduling stats:
+ */
+static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int flags)
+{
+	struct cfs_rq *cfs_rq;
+	struct sched_entity *se = &p->se;
+	int task_sleep = flags & DEQUEUE_SLEEP;
+
+	for_each_sched_entity(se) {
+		cfs_rq = cfs_rq_of(se);
+		dequeue_entity(cfs_rq, se, flags);
+
+		/*
+		 * end evaluation on encountering a throttled cfs_rq
+		 *
+		 * note: in the case of encountering a throttled cfs_rq we will
+		 * post the final h_nr_running decrement below.
+		*/
+		if (cfs_rq_throttled(cfs_rq))
+			break;
+		cfs_rq->h_nr_running--;
+
+		/* Don't dequeue parent if it has other entities besides us */
+		if (cfs_rq->load.weight) {
+			/*
+			 * Bias pick_next to pick a task from this cfs_rq, as
+			 * p is sleeping when it is within its sched_slice.
+			 */
+			if (task_sleep && parent_entity(se))
+				set_next_buddy(parent_entity(se));
+
+			/* avoid re-evaluating load for this entity */
+			se = parent_entity(se);
+			break;
+		}
+		flags |= DEQUEUE_SLEEP;
+	}
+
+	for_each_sched_entity(se) {
+		cfs_rq = cfs_rq_of(se);
+		cfs_rq->h_nr_running--;
+
+		if (cfs_rq_throttled(cfs_rq))
+			break;
+
+		update_cfs_load(cfs_rq, 0);
+		update_cfs_shares(cfs_rq);
+	}
+
+	if (!se)
+		dec_nr_running(rq);
+	hrtick_update(rq);
+}
+
+#ifdef CONFIG_SMP
+/* Used instead of source_load when we know the type == 0 */
+static unsigned long weighted_cpuload(const int cpu)
+{
+	return cpu_rq(cpu)->load.weight;
+}
+
+/*
+ * Return a low guess at the load of a migration-source cpu weighted
+ * according to the scheduling class and "nice" value.
+ *
+ * We want to under-estimate the load of migration sources, to
+ * balance conservatively.
+ */
+static unsigned long source_load(int cpu, int type)
+{
+	struct rq *rq = cpu_rq(cpu);
+	unsigned long total = weighted_cpuload(cpu);
+
+	if (type == 0 || !sched_feat(LB_BIAS))
+		return total;
+
+	return min(rq->cpu_load[type-1], total);
+}
+
+/*
+ * Return a high guess at the load of a migration-target cpu weighted
+ * according to the scheduling class and "nice" value.
+ */
+static unsigned long target_load(int cpu, int type)
+{
+	struct rq *rq = cpu_rq(cpu);
+	unsigned long total = weighted_cpuload(cpu);
+
+	if (type == 0 || !sched_feat(LB_BIAS))
+		return total;
+
+	return max(rq->cpu_load[type-1], total);
+}
+
+static unsigned long power_of(int cpu)
+{
+	return cpu_rq(cpu)->cpu_power;
+}
+
+static unsigned long cpu_avg_load_per_task(int cpu)
+{
+	struct rq *rq = cpu_rq(cpu);
+	unsigned long nr_running = ACCESS_ONCE(rq->nr_running);
+
+	if (nr_running)
+		return rq->load.weight / nr_running;
+
+	return 0;
+}
+
+
+static void task_waking_fair(struct task_struct *p)
+{
+	struct sched_entity *se = &p->se;
+	struct cfs_rq *cfs_rq = cfs_rq_of(se);
+	u64 min_vruntime;
+
+#ifndef CONFIG_64BIT
+	u64 min_vruntime_copy;
+
+	do {
+		min_vruntime_copy = cfs_rq->min_vruntime_copy;
+		smp_rmb();
+		min_vruntime = cfs_rq->min_vruntime;
+	} while (min_vruntime != min_vruntime_copy);
+#else
+	min_vruntime = cfs_rq->min_vruntime;
+#endif
+
+	se->vruntime -= min_vruntime;
+}
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+/*
+ * effective_load() calculates the load change as seen from the root_task_group
+ *
+ * Adding load to a group doesn't make a group heavier, but can cause movement
+ * of group shares between cpus. Assuming the shares were perfectly aligned one
+ * can calculate the shift in shares.
+ *
+ * Calculate the effective load difference if @wl is added (subtracted) to @tg
+ * on this @cpu and results in a total addition (subtraction) of @wg to the
+ * total group weight.
+ *
+ * Given a runqueue weight distribution (rw_i) we can compute a shares
+ * distribution (s_i) using:
+ *
+ *   s_i = rw_i / \Sum rw_j						(1)
+ *
+ * Suppose we have 4 CPUs and our @tg is a direct child of the root group and
+ * has 7 equal weight tasks, distributed as below (rw_i), with the resulting
+ * shares distribution (s_i):
+ *
+ *   rw_i = {   2,   4,   1,   0 }
+ *   s_i  = { 2/7, 4/7, 1/7,   0 }
+ *
+ * As per wake_affine() we're interested in the load of two CPUs (the CPU the
+ * task used to run on and the CPU the waker is running on), we need to
+ * compute the effect of waking a task on either CPU and, in case of a sync
+ * wakeup, compute the effect of the current task going to sleep.
+ *
+ * So for a change of @wl to the local @cpu with an overall group weight change
+ * of @wl we can compute the new shares distribution (s'_i) using:
+ *
+ *   s'_i = (rw_i + @wl) / (@wg + \Sum rw_j)				(2)
+ *
+ * Suppose we're interested in CPUs 0 and 1, and want to compute the load
+ * differences in waking a task to CPU 0. The additional task changes the
+ * weight and shares distributions like:
+ *
+ *   rw'_i = {   3,   4,   1,   0 }
+ *   s'_i  = { 3/8, 4/8, 1/8,   0 }
+ *
+ * We can then compute the difference in effective weight by using:
+ *
+ *   dw_i = S * (s'_i - s_i)						(3)
+ *
+ * Where 'S' is the group weight as seen by its parent.
+ *
+ * Therefore the effective change in loads on CPU 0 would be 5/56 (3/8 - 2/7)
+ * times the weight of the group. The effect on CPU 1 would be -4/56 (4/8 -
+ * 4/7) times the weight of the group.
+ */
+static long effective_load(struct task_group *tg, int cpu, long wl, long wg)
+{
+	struct sched_entity *se = tg->se[cpu];
+
+	if (!tg->parent)	/* the trivial, non-cgroup case */
+		return wl;
+
+	for_each_sched_entity(se) {
+		long w, W;
+
+		tg = se->my_q->tg;
+
+		/*
+		 * W = @wg + \Sum rw_j
+		 */
+		W = wg + calc_tg_weight(tg, se->my_q);
+
+		/*
+		 * w = rw_i + @wl
+		 */
+		w = se->my_q->load.weight + wl;
+
+		/*
+		 * wl = S * s'_i; see (2)
+		 */
+		if (W > 0 && w < W)
+			wl = (w * tg->shares) / W;
+		else
+			wl = tg->shares;
+
+		/*
+		 * Per the above, wl is the new se->load.weight value; since
+		 * those are clipped to [MIN_SHARES, ...) do so now. See
+		 * calc_cfs_shares().
+		 */
+		if (wl < MIN_SHARES)
+			wl = MIN_SHARES;
+
+		/*
+		 * wl = dw_i = S * (s'_i - s_i); see (3)
+		 */
+		wl -= se->load.weight;
+
+		/*
+		 * Recursively apply this logic to all parent groups to compute
+		 * the final effective load change on the root group. Since
+		 * only the @tg group gets extra weight, all parent groups can
+		 * only redistribute existing shares. @wl is the shift in shares
+		 * resulting from this level per the above.
+		 */
+		wg = 0;
+	}
+
+	return wl;
+}
+#else
+
+static inline unsigned long effective_load(struct task_group *tg, int cpu,
+		unsigned long wl, unsigned long wg)
+{
+	return wl;
+}
+
+#endif
+
+static int wake_affine(struct sched_domain *sd, struct task_struct *p, int sync)
+{
+	s64 this_load, load;
+	int idx, this_cpu, prev_cpu;
+	unsigned long tl_per_task;
+	struct task_group *tg;
+	unsigned long weight;
+	int balanced;
+
+	idx	  = sd->wake_idx;
+	this_cpu  = smp_processor_id();
+	prev_cpu  = task_cpu(p);
+	load	  = source_load(prev_cpu, idx);
+	this_load = target_load(this_cpu, idx);
+
+	/*
+	 * If sync wakeup then subtract the (maximum possible)
+	 * effect of the currently running task from the load
+	 * of the current CPU:
+	 */
+	if (sync) {
+		tg = task_group(current);
+		weight = current->se.load.weight;
+
+		this_load += effective_load(tg, this_cpu, -weight, -weight);
+		load += effective_load(tg, prev_cpu, 0, -weight);
+	}
+
+	tg = task_group(p);
+	weight = p->se.load.weight;
+
+	/*
+	 * In low-load situations, where prev_cpu is idle and this_cpu is idle
+	 * due to the sync cause above having dropped this_load to 0, we'll
+	 * always have an imbalance, but there's really nothing you can do
+	 * about that, so that's good too.
+	 *
+	 * Otherwise check if either cpus are near enough in load to allow this
+	 * task to be woken on this_cpu.
+	 */
+	if (this_load > 0) {
+		s64 this_eff_load, prev_eff_load;
+
+		this_eff_load = 100;
+		this_eff_load *= power_of(prev_cpu);
+		this_eff_load *= this_load +
+			effective_load(tg, this_cpu, weight, weight);
+
+		prev_eff_load = 100 + (sd->imbalance_pct - 100) / 2;
+		prev_eff_load *= power_of(this_cpu);
+		prev_eff_load *= load + effective_load(tg, prev_cpu, 0, weight);
+
+		balanced = this_eff_load <= prev_eff_load;
+	} else
+		balanced = true;
+
+	/*
+	 * If the currently running task will sleep within
+	 * a reasonable amount of time then attract this newly
+	 * woken task:
+	 */
+	if (sync && balanced)
+		return 1;
+
+	schedstat_inc(p, se.statistics.nr_wakeups_affine_attempts);
+	tl_per_task = cpu_avg_load_per_task(this_cpu);
+
+	if (balanced ||
+	    (this_load <= load &&
+	     this_load + target_load(prev_cpu, idx) <= tl_per_task)) {
+		/*
+		 * This domain has SD_WAKE_AFFINE and
+		 * p is cache cold in this domain, and
+		 * there is no bad imbalance.
+		 */
+		schedstat_inc(sd, ttwu_move_affine);
+		schedstat_inc(p, se.statistics.nr_wakeups_affine);
+
+		return 1;
+	}
+	return 0;
+}
+
+/*
+ * find_idlest_group finds and returns the least busy CPU group within the
+ * domain.
+ */
+static struct sched_group *
+find_idlest_group(struct sched_domain *sd, struct task_struct *p,
+		  int this_cpu, int load_idx)
+{
+	struct sched_group *idlest = NULL, *group = sd->groups;
+	unsigned long min_load = ULONG_MAX, this_load = 0;
+	int imbalance = 100 + (sd->imbalance_pct-100)/2;
+
+	do {
+		unsigned long load, avg_load;
+		int local_group;
+		int i;
+
+		/* Skip over this group if it has no CPUs allowed */
+		if (!cpumask_intersects(sched_group_cpus(group),
+					tsk_cpus_allowed(p)))
+			continue;
+
+		local_group = cpumask_test_cpu(this_cpu,
+					       sched_group_cpus(group));
+
+		/* Tally up the load of all CPUs in the group */
+		avg_load = 0;
+
+		for_each_cpu(i, sched_group_cpus(group)) {
+			/* Bias balancing toward cpus of our domain */
+			if (local_group)
+				load = source_load(i, load_idx);
+			else
+				load = target_load(i, load_idx);
+
+			avg_load += load;
+		}
+
+		/* Adjust by relative CPU power of the group */
+		avg_load = (avg_load * SCHED_POWER_SCALE) / group->sgp->power;
+
+		if (local_group) {
+			this_load = avg_load;
+		} else if (avg_load < min_load) {
+			min_load = avg_load;
+			idlest = group;
+		}
+	} while (group = group->next, group != sd->groups);
+
+	if (!idlest || 100*this_load < imbalance*min_load)
+		return NULL;
+	return idlest;
+}
+
+/*
+ * find_idlest_cpu - find the idlest cpu among the cpus in group.
+ */
+static int
+find_idlest_cpu(struct sched_group *group, struct task_struct *p, int this_cpu)
+{
+	unsigned long load, min_load = ULONG_MAX;
+	int idlest = -1;
+	int i;
+
+	/* Traverse only the allowed CPUs */
+	for_each_cpu_and(i, sched_group_cpus(group), tsk_cpus_allowed(p)) {
+		load = weighted_cpuload(i);
+
+		if (load < min_load || (load == min_load && i == this_cpu)) {
+			min_load = load;
+			idlest = i;
+		}
+	}
+
+	return idlest;
+}
+
+/*
+ * Try and locate an idle CPU in the sched_domain.
+ */
+static int select_idle_sibling(struct task_struct *p, int target)
+{
+	int cpu = smp_processor_id();
+	int prev_cpu = task_cpu(p);
+	struct sched_domain *sd;
+	struct sched_group *sg;
+	int i;
+
+	/*
+	 * If the task is going to be woken-up on this cpu and if it is
+	 * already idle, then it is the right target.
+	 */
+	if (target == cpu && idle_cpu(cpu))
+		return cpu;
+
+	/*
+	 * If the task is going to be woken-up on the cpu where it previously
+	 * ran and if it is currently idle, then it the right target.
+	 */
+	if (target == prev_cpu && idle_cpu(prev_cpu))
+		return prev_cpu;
+
+	/*
+	 * Otherwise, iterate the domains and find an elegible idle cpu.
+	 */
+	rcu_read_lock();
+
+	sd = rcu_dereference(per_cpu(sd_llc, target));
+	for_each_lower_domain(sd) {
+		sg = sd->groups;
+		do {
+			if (!cpumask_intersects(sched_group_cpus(sg),
+						tsk_cpus_allowed(p)))
+				goto next;
+
+			for_each_cpu(i, sched_group_cpus(sg)) {
+				if (!idle_cpu(i))
+					goto next;
+			}
+
+			target = cpumask_first_and(sched_group_cpus(sg),
+					tsk_cpus_allowed(p));
+			goto done;
+next:
+			sg = sg->next;
+		} while (sg != sd->groups);
+	}
+done:
+	rcu_read_unlock();
+
+	return target;
+}
+
+/*
+ * sched_balance_self: balance the current task (running on cpu) in domains
+ * that have the 'flag' flag set. In practice, this is SD_BALANCE_FORK and
+ * SD_BALANCE_EXEC.
+ *
+ * Balance, ie. select the least loaded group.
+ *
+ * Returns the target CPU number, or the same CPU if no balancing is needed.
+ *
+ * preempt must be disabled.
+ */
+static int
+select_task_rq_fair(struct task_struct *p, int sd_flag, int wake_flags)
+{
+	struct sched_domain *tmp, *affine_sd = NULL, *sd = NULL;
+	int cpu = smp_processor_id();
+	int prev_cpu = task_cpu(p);
+	int new_cpu = cpu;
+	int want_affine = 0;
+	int want_sd = 1;
+	int sync = wake_flags & WF_SYNC;
+
+	if (p->rt.nr_cpus_allowed == 1)
+		return prev_cpu;
+
+	if (sd_flag & SD_BALANCE_WAKE) {
+		if (cpumask_test_cpu(cpu, tsk_cpus_allowed(p)))
+			want_affine = 1;
+		new_cpu = prev_cpu;
+	}
+
+	rcu_read_lock();
+	for_each_domain(cpu, tmp) {
+		if (!(tmp->flags & SD_LOAD_BALANCE))
+			continue;
+
+		/*
+		 * If power savings logic is enabled for a domain, see if we
+		 * are not overloaded, if so, don't balance wider.
+		 */
+		if (tmp->flags & (SD_POWERSAVINGS_BALANCE|SD_PREFER_LOCAL)) {
+			unsigned long power = 0;
+			unsigned long nr_running = 0;
+			unsigned long capacity;
+			int i;
+
+			for_each_cpu(i, sched_domain_span(tmp)) {
+				power += power_of(i);
+				nr_running += cpu_rq(i)->cfs.nr_running;
+			}
+
+			capacity = DIV_ROUND_CLOSEST(power, SCHED_POWER_SCALE);
+
+			if (tmp->flags & SD_POWERSAVINGS_BALANCE)
+				nr_running /= 2;
+
+			if (nr_running < capacity)
+				want_sd = 0;
+		}
+
+		/*
+		 * If both cpu and prev_cpu are part of this domain,
+		 * cpu is a valid SD_WAKE_AFFINE target.
+		 */
+		if (want_affine && (tmp->flags & SD_WAKE_AFFINE) &&
+		    cpumask_test_cpu(prev_cpu, sched_domain_span(tmp))) {
+			affine_sd = tmp;
+			want_affine = 0;
+		}
+
+		if (!want_sd && !want_affine)
+			break;
+
+		if (!(tmp->flags & sd_flag))
+			continue;
+
+		if (want_sd)
+			sd = tmp;
+	}
+
+	if (affine_sd) {
+		if (cpu == prev_cpu || wake_affine(affine_sd, p, sync))
+			prev_cpu = cpu;
+
+		new_cpu = select_idle_sibling(p, prev_cpu);
+		goto unlock;
+	}
+
+	while (sd) {
+		int load_idx = sd->forkexec_idx;
+		struct sched_group *group;
+		int weight;
+
+		if (!(sd->flags & sd_flag)) {
+			sd = sd->child;
+			continue;
+		}
+
+		if (sd_flag & SD_BALANCE_WAKE)
+			load_idx = sd->wake_idx;
+
+		group = find_idlest_group(sd, p, cpu, load_idx);
+		if (!group) {
+			sd = sd->child;
+			continue;
+		}
+
+		new_cpu = find_idlest_cpu(group, p, cpu);
+		if (new_cpu == -1 || new_cpu == cpu) {
+			/* Now try balancing at a lower domain level of cpu */
+			sd = sd->child;
+			continue;
+		}
+
+		/* Now try balancing at a lower domain level of new_cpu */
+		cpu = new_cpu;
+		weight = sd->span_weight;
+		sd = NULL;
+		for_each_domain(cpu, tmp) {
+			if (weight <= tmp->span_weight)
+				break;
+			if (tmp->flags & sd_flag)
+				sd = tmp;
+		}
+		/* while loop will break here if sd == NULL */
+	}
+unlock:
+	rcu_read_unlock();
+
+	return new_cpu;
+}
+#endif /* CONFIG_SMP */
+
+static unsigned long
+wakeup_gran(struct sched_entity *curr, struct sched_entity *se)
+{
+	unsigned long gran = sysctl_sched_wakeup_granularity;
+
+	/*
+	 * Since its curr running now, convert the gran from real-time
+	 * to virtual-time in his units.
+	 *
+	 * By using 'se' instead of 'curr' we penalize light tasks, so
+	 * they get preempted easier. That is, if 'se' < 'curr' then
+	 * the resulting gran will be larger, therefore penalizing the
+	 * lighter, if otoh 'se' > 'curr' then the resulting gran will
+	 * be smaller, again penalizing the lighter task.
+	 *
+	 * This is especially important for buddies when the leftmost
+	 * task is higher priority than the buddy.
+	 */
+	return calc_delta_fair(gran, se);
+}
+
+/*
+ * Should 'se' preempt 'curr'.
+ *
+ *             |s1
+ *        |s2
+ *   |s3
+ *         g
+ *      |<--->|c
+ *
+ *  w(c, s1) = -1
+ *  w(c, s2) =  0
+ *  w(c, s3) =  1
+ *
+ */
+static int
+wakeup_preempt_entity(struct sched_entity *curr, struct sched_entity *se)
+{
+	s64 gran, vdiff = curr->vruntime - se->vruntime;
+
+	if (vdiff <= 0)
+		return -1;
+
+	gran = wakeup_gran(curr, se);
+	if (vdiff > gran)
+		return 1;
+
+	return 0;
+}
+
+static void set_last_buddy(struct sched_entity *se)
+{
+	if (entity_is_task(se) && unlikely(task_of(se)->policy == SCHED_IDLE))
+		return;
+
+	for_each_sched_entity(se)
+		cfs_rq_of(se)->last = se;
+}
+
+static void set_next_buddy(struct sched_entity *se)
+{
+	if (entity_is_task(se) && unlikely(task_of(se)->policy == SCHED_IDLE))
+		return;
+
+	for_each_sched_entity(se)
+		cfs_rq_of(se)->next = se;
+}
+
+static void set_skip_buddy(struct sched_entity *se)
+{
+	for_each_sched_entity(se)
+		cfs_rq_of(se)->skip = se;
+}
+
+/*
+ * Preempt the current task with a newly woken task if needed:
+ */
+static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int wake_flags)
+{
+	struct task_struct *curr = rq->curr;
+	struct sched_entity *se = &curr->se, *pse = &p->se;
+	struct cfs_rq *cfs_rq = task_cfs_rq(curr);
+	int scale = cfs_rq->nr_running >= sched_nr_latency;
+	int next_buddy_marked = 0;
+
+	if (unlikely(se == pse))
+		return;
+
+	/*
+	 * This is possible from callers such as pull_task(), in which we
+	 * unconditionally check_prempt_curr() after an enqueue (which may have
+	 * lead to a throttle).  This both saves work and prevents false
+	 * next-buddy nomination below.
+	 */
+	if (unlikely(throttled_hierarchy(cfs_rq_of(pse))))
+		return;
+
+	if (sched_feat(NEXT_BUDDY) && scale && !(wake_flags & WF_FORK)) {
+		set_next_buddy(pse);
+		next_buddy_marked = 1;
+	}
+
+	/*
+	 * We can come here with TIF_NEED_RESCHED already set from new task
+	 * wake up path.
+	 *
+	 * Note: this also catches the edge-case of curr being in a throttled
+	 * group (e.g. via set_curr_task), since update_curr() (in the
+	 * enqueue of curr) will have resulted in resched being set.  This
+	 * prevents us from potentially nominating it as a false LAST_BUDDY
+	 * below.
+	 */
+	if (test_tsk_need_resched(curr))
+		return;
+
+	/* Idle tasks are by definition preempted by non-idle tasks. */
+	if (unlikely(curr->policy == SCHED_IDLE) &&
+	    likely(p->policy != SCHED_IDLE))
+		goto preempt;
+
+	/*
+	 * Batch and idle tasks do not preempt non-idle tasks (their preemption
+	 * is driven by the tick):
+	 */
+	if (unlikely(p->policy != SCHED_NORMAL))
+		return;
+
+	find_matching_se(&se, &pse);
+	update_curr(cfs_rq_of(se));
+	BUG_ON(!pse);
+	if (wakeup_preempt_entity(se, pse) == 1) {
+		/*
+		 * Bias pick_next to pick the sched entity that is
+		 * triggering this preemption.
+		 */
+		if (!next_buddy_marked)
+			set_next_buddy(pse);
+		goto preempt;
+	}
+
+	return;
+
+preempt:
+	resched_task(curr);
+	/*
+	 * Only set the backward buddy when the current task is still
+	 * on the rq. This can happen when a wakeup gets interleaved
+	 * with schedule on the ->pre_schedule() or idle_balance()
+	 * point, either of which can * drop the rq lock.
+	 *
+	 * Also, during early boot the idle thread is in the fair class,
+	 * for obvious reasons its a bad idea to schedule back to it.
+	 */
+	if (unlikely(!se->on_rq || curr == rq->idle))
+		return;
+
+	if (sched_feat(LAST_BUDDY) && scale && entity_is_task(se))
+		set_last_buddy(se);
+}
+
+static struct task_struct *pick_next_task_fair(struct rq *rq)
+{
+	struct task_struct *p;
+	struct cfs_rq *cfs_rq = &rq->cfs;
+	struct sched_entity *se;
+
+	if (!cfs_rq->nr_running)
+		return NULL;
+
+	do {
+		se = pick_next_entity(cfs_rq);
+		set_next_entity(cfs_rq, se);
+		cfs_rq = group_cfs_rq(se);
+	} while (cfs_rq);
+
+	p = task_of(se);
+	if (hrtick_enabled(rq))
+		hrtick_start_fair(rq, p);
+
+	return p;
+}
+
+/*
+ * Account for a descheduled task:
+ */
+static void put_prev_task_fair(struct rq *rq, struct task_struct *prev)
+{
+	struct sched_entity *se = &prev->se;
+	struct cfs_rq *cfs_rq;
+
+	for_each_sched_entity(se) {
+		cfs_rq = cfs_rq_of(se);
+		put_prev_entity(cfs_rq, se);
+	}
+}
+
+/*
+ * sched_yield() is very simple
+ *
+ * The magic of dealing with the ->skip buddy is in pick_next_entity.
+ */
+static void yield_task_fair(struct rq *rq)
+{
+	struct task_struct *curr = rq->curr;
+	struct cfs_rq *cfs_rq = task_cfs_rq(curr);
+	struct sched_entity *se = &curr->se;
+
+	/*
+	 * Are we the only task in the tree?
+	 */
+	if (unlikely(rq->nr_running == 1))
+		return;
+
+	clear_buddies(cfs_rq, se);
+
+	if (curr->policy != SCHED_BATCH) {
+		update_rq_clock(rq);
+		/*
+		 * Update run-time statistics of the 'current'.
+		 */
+		update_curr(cfs_rq);
+		/*
+		 * Tell update_rq_clock() that we've just updated,
+		 * so we don't do microscopic update in schedule()
+		 * and double the fastpath cost.
+		 */
+		 rq->skip_clock_update = 1;
+	}
+
+	set_skip_buddy(se);
+}
+
+static bool yield_to_task_fair(struct rq *rq, struct task_struct *p, bool preempt)
+{
+	struct sched_entity *se = &p->se;
+
+	/* throttled hierarchies are not runnable */
+	if (!se->on_rq || throttled_hierarchy(cfs_rq_of(se)))
+		return false;
+
+	/* Tell the scheduler that we'd really like pse to run next. */
+	set_next_buddy(se);
+
+	yield_task_fair(rq);
+
+	return true;
+}
+
+#ifdef CONFIG_SMP
+/**************************************************
+ * Fair scheduling class load-balancing methods:
+ */
+
+/*
+ * pull_task - move a task from a remote runqueue to the local runqueue.
+ * Both runqueues must be locked.
+ */
+static void pull_task(struct rq *src_rq, struct task_struct *p,
+		      struct rq *this_rq, int this_cpu)
+{
+	deactivate_task(src_rq, p, 0);
+	set_task_cpu(p, this_cpu);
+	activate_task(this_rq, p, 0);
+	check_preempt_curr(this_rq, p, 0);
+}
+
+/*
+ * Is this task likely cache-hot:
+ */
+static int
+task_hot(struct task_struct *p, u64 now, struct sched_domain *sd)
+{
+	s64 delta;
+
+	if (p->sched_class != &fair_sched_class)
+		return 0;
+
+	if (unlikely(p->policy == SCHED_IDLE))
+		return 0;
+
+	/*
+	 * Buddy candidates are cache hot:
+	 */
+	if (sched_feat(CACHE_HOT_BUDDY) && this_rq()->nr_running &&
+			(&p->se == cfs_rq_of(&p->se)->next ||
+			 &p->se == cfs_rq_of(&p->se)->last))
+		return 1;
+
+	if (sysctl_sched_migration_cost == -1)
+		return 1;
+	if (sysctl_sched_migration_cost == 0)
+		return 0;
+
+	delta = now - p->se.exec_start;
+
+	return delta < (s64)sysctl_sched_migration_cost;
+}
+
+#define LBF_ALL_PINNED	0x01
+#define LBF_NEED_BREAK	0x02	/* clears into HAD_BREAK */
+#define LBF_HAD_BREAK	0x04
+#define LBF_HAD_BREAKS	0x0C	/* count HAD_BREAKs overflows into ABORT */
+#define LBF_ABORT	0x10
+
+/*
+ * can_migrate_task - may task p from runqueue rq be migrated to this_cpu?
+ */
+static
+int can_migrate_task(struct task_struct *p, struct rq *rq, int this_cpu,
+		     struct sched_domain *sd, enum cpu_idle_type idle,
+		     int *lb_flags)
+{
+	int tsk_cache_hot = 0;
+	/*
+	 * We do not migrate tasks that are:
+	 * 1) running (obviously), or
+	 * 2) cannot be migrated to this CPU due to cpus_allowed, or
+	 * 3) are cache-hot on their current CPU.
+	 */
+	if (!cpumask_test_cpu(this_cpu, tsk_cpus_allowed(p))) {
+		schedstat_inc(p, se.statistics.nr_failed_migrations_affine);
+		return 0;
+	}
+	*lb_flags &= ~LBF_ALL_PINNED;
+
+	if (task_running(rq, p)) {
+		schedstat_inc(p, se.statistics.nr_failed_migrations_running);
+		return 0;
+	}
+
+	/*
+	 * Aggressive migration if:
+	 * 1) task is cache cold, or
+	 * 2) too many balance attempts have failed.
+	 */
+
+	tsk_cache_hot = task_hot(p, rq->clock_task, sd);
+	if (!tsk_cache_hot ||
+		sd->nr_balance_failed > sd->cache_nice_tries) {
+#ifdef CONFIG_SCHEDSTATS
+		if (tsk_cache_hot) {
+			schedstat_inc(sd, lb_hot_gained[idle]);
+			schedstat_inc(p, se.statistics.nr_forced_migrations);
+		}
+#endif
+		return 1;
+	}
+
+	if (tsk_cache_hot) {
+		schedstat_inc(p, se.statistics.nr_failed_migrations_hot);
+		return 0;
+	}
+	return 1;
+}
+
+/*
+ * move_one_task tries to move exactly one task from busiest to this_rq, as
+ * part of active balancing operations within "domain".
+ * Returns 1 if successful and 0 otherwise.
+ *
+ * Called with both runqueues locked.
+ */
+static int
+move_one_task(struct rq *this_rq, int this_cpu, struct rq *busiest,
+	      struct sched_domain *sd, enum cpu_idle_type idle)
+{
+	struct task_struct *p, *n;
+	struct cfs_rq *cfs_rq;
+	int pinned = 0;
+
+	for_each_leaf_cfs_rq(busiest, cfs_rq) {
+		list_for_each_entry_safe(p, n, &cfs_rq->tasks, se.group_node) {
+			if (throttled_lb_pair(task_group(p),
+					      busiest->cpu, this_cpu))
+				break;
+
+			if (!can_migrate_task(p, busiest, this_cpu,
+						sd, idle, &pinned))
+				continue;
+
+			pull_task(busiest, p, this_rq, this_cpu);
+			/*
+			 * Right now, this is only the second place pull_task()
+			 * is called, so we can safely collect pull_task()
+			 * stats here rather than inside pull_task().
+			 */
+			schedstat_inc(sd, lb_gained[idle]);
+			return 1;
+		}
+	}
+
+	return 0;
+}
+
+static unsigned long
+balance_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest,
+	      unsigned long max_load_move, struct sched_domain *sd,
+	      enum cpu_idle_type idle, int *lb_flags,
+	      struct cfs_rq *busiest_cfs_rq)
+{
+	int loops = 0, pulled = 0;
+	long rem_load_move = max_load_move;
+	struct task_struct *p, *n;
+
+	if (max_load_move == 0)
+		goto out;
+
+	list_for_each_entry_safe(p, n, &busiest_cfs_rq->tasks, se.group_node) {
+		if (loops++ > sysctl_sched_nr_migrate) {
+			*lb_flags |= LBF_NEED_BREAK;
+			break;
+		}
+
+		if ((p->se.load.weight >> 1) > rem_load_move ||
+		    !can_migrate_task(p, busiest, this_cpu, sd, idle,
+				      lb_flags))
+			continue;
+
+		pull_task(busiest, p, this_rq, this_cpu);
+		pulled++;
+		rem_load_move -= p->se.load.weight;
+
+#ifdef CONFIG_PREEMPT
+		/*
+		 * NEWIDLE balancing is a source of latency, so preemptible
+		 * kernels will stop after the first task is pulled to minimize
+		 * the critical section.
+		 */
+		if (idle == CPU_NEWLY_IDLE) {
+			*lb_flags |= LBF_ABORT;
+			break;
+		}
+#endif
+
+		/*
+		 * We only want to steal up to the prescribed amount of
+		 * weighted load.
+		 */
+		if (rem_load_move <= 0)
+			break;
+	}
+out:
+	/*
+	 * Right now, this is one of only two places pull_task() is called,
+	 * so we can safely collect pull_task() stats here rather than
+	 * inside pull_task().
+	 */
+	schedstat_add(sd, lb_gained[idle], pulled);
+
+	return max_load_move - rem_load_move;
+}
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+/*
+ * update tg->load_weight by folding this cpu's load_avg
+ */
+static int update_shares_cpu(struct task_group *tg, int cpu)
+{
+	struct cfs_rq *cfs_rq;
+	unsigned long flags;
+	struct rq *rq;
+
+	if (!tg->se[cpu])
+		return 0;
+
+	rq = cpu_rq(cpu);
+	cfs_rq = tg->cfs_rq[cpu];
+
+	raw_spin_lock_irqsave(&rq->lock, flags);
+
+	update_rq_clock(rq);
+	update_cfs_load(cfs_rq, 1);
+
+	/*
+	 * We need to update shares after updating tg->load_weight in
+	 * order to adjust the weight of groups with long running tasks.
+	 */
+	update_cfs_shares(cfs_rq);
+
+	raw_spin_unlock_irqrestore(&rq->lock, flags);
+
+	return 0;
+}
+
+static void update_shares(int cpu)
+{
+	struct cfs_rq *cfs_rq;
+	struct rq *rq = cpu_rq(cpu);
+
+	rcu_read_lock();
+	/*
+	 * Iterates the task_group tree in a bottom up fashion, see
+	 * list_add_leaf_cfs_rq() for details.
+	 */
+	for_each_leaf_cfs_rq(rq, cfs_rq) {
+		/* throttled entities do not contribute to load */
+		if (throttled_hierarchy(cfs_rq))
+			continue;
+
+		update_shares_cpu(cfs_rq->tg, cpu);
+	}
+	rcu_read_unlock();
+}
+
+/*
+ * Compute the cpu's hierarchical load factor for each task group.
+ * This needs to be done in a top-down fashion because the load of a child
+ * group is a fraction of its parents load.
+ */
+static int tg_load_down(struct task_group *tg, void *data)
+{
+	unsigned long load;
+	long cpu = (long)data;
+
+	if (!tg->parent) {
+		load = cpu_rq(cpu)->load.weight;
+	} else {
+		load = tg->parent->cfs_rq[cpu]->h_load;
+		load *= tg->se[cpu]->load.weight;
+		load /= tg->parent->cfs_rq[cpu]->load.weight + 1;
+	}
+
+	tg->cfs_rq[cpu]->h_load = load;
+
+	return 0;
+}
+
+static void update_h_load(long cpu)
+{
+	walk_tg_tree(tg_load_down, tg_nop, (void *)cpu);
+}
+
+static unsigned long
+load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
+		  unsigned long max_load_move,
+		  struct sched_domain *sd, enum cpu_idle_type idle,
+		  int *lb_flags)
+{
+	long rem_load_move = max_load_move;
+	struct cfs_rq *busiest_cfs_rq;
+
+	rcu_read_lock();
+	update_h_load(cpu_of(busiest));
+
+	for_each_leaf_cfs_rq(busiest, busiest_cfs_rq) {
+		unsigned long busiest_h_load = busiest_cfs_rq->h_load;
+		unsigned long busiest_weight = busiest_cfs_rq->load.weight;
+		u64 rem_load, moved_load;
+
+		if (*lb_flags & (LBF_NEED_BREAK|LBF_ABORT))
+			break;
+
+		/*
+		 * empty group or part of a throttled hierarchy
+		 */
+		if (!busiest_cfs_rq->task_weight ||
+		    throttled_lb_pair(busiest_cfs_rq->tg, cpu_of(busiest), this_cpu))
+			continue;
+
+		rem_load = (u64)rem_load_move * busiest_weight;
+		rem_load = div_u64(rem_load, busiest_h_load + 1);
+
+		moved_load = balance_tasks(this_rq, this_cpu, busiest,
+				rem_load, sd, idle, lb_flags,
+				busiest_cfs_rq);
+
+		if (!moved_load)
+			continue;
+
+		moved_load *= busiest_h_load;
+		moved_load = div_u64(moved_load, busiest_weight + 1);
+
+		rem_load_move -= moved_load;
+		if (rem_load_move < 0)
+			break;
+	}
+	rcu_read_unlock();
+
+	return max_load_move - rem_load_move;
+}
+#else
+static inline void update_shares(int cpu)
+{
+}
+
+static unsigned long
+load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
+		  unsigned long max_load_move,
+		  struct sched_domain *sd, enum cpu_idle_type idle,
+		  int *lb_flags)
+{
+	return balance_tasks(this_rq, this_cpu, busiest,
+			max_load_move, sd, idle, lb_flags,
+			&busiest->cfs);
+}
+#endif
+
+/*
+ * move_tasks tries to move up to max_load_move weighted load from busiest to
+ * this_rq, as part of a balancing operation within domain "sd".
+ * Returns 1 if successful and 0 otherwise.
+ *
+ * Called with both runqueues locked.
+ */
+static int move_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest,
+		      unsigned long max_load_move,
+		      struct sched_domain *sd, enum cpu_idle_type idle,
+		      int *lb_flags)
+{
+	unsigned long total_load_moved = 0, load_moved;
+
+	do {
+		load_moved = load_balance_fair(this_rq, this_cpu, busiest,
+				max_load_move - total_load_moved,
+				sd, idle, lb_flags);
+
+		total_load_moved += load_moved;
+
+		if (*lb_flags & (LBF_NEED_BREAK|LBF_ABORT))
+			break;
+
+#ifdef CONFIG_PREEMPT
+		/*
+		 * NEWIDLE balancing is a source of latency, so preemptible
+		 * kernels will stop after the first task is pulled to minimize
+		 * the critical section.
+		 */
+		if (idle == CPU_NEWLY_IDLE && this_rq->nr_running) {
+			*lb_flags |= LBF_ABORT;
+			break;
+		}
+#endif
+	} while (load_moved && max_load_move > total_load_moved);
+
+	return total_load_moved > 0;
+}
+
+/********** Helpers for find_busiest_group ************************/
+/*
+ * sd_lb_stats - Structure to store the statistics of a sched_domain
+ * 		during load balancing.
+ */
+struct sd_lb_stats {
+	struct sched_group *busiest; /* Busiest group in this sd */
+	struct sched_group *this;  /* Local group in this sd */
+	unsigned long total_load;  /* Total load of all groups in sd */
+	unsigned long total_pwr;   /*	Total power of all groups in sd */
+	unsigned long avg_load;	   /* Average load across all groups in sd */
+
+	/** Statistics of this group */
+	unsigned long this_load;
+	unsigned long this_load_per_task;
+	unsigned long this_nr_running;
+	unsigned long this_has_capacity;
+	unsigned int  this_idle_cpus;
+
+	/* Statistics of the busiest group */
+	unsigned int  busiest_idle_cpus;
+	unsigned long max_load;
+	unsigned long busiest_load_per_task;
+	unsigned long busiest_nr_running;
+	unsigned long busiest_group_capacity;
+	unsigned long busiest_has_capacity;
+	unsigned int  busiest_group_weight;
+
+	int group_imb; /* Is there imbalance in this sd */
+#if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT)
+	int power_savings_balance; /* Is powersave balance needed for this sd */
+	struct sched_group *group_min; /* Least loaded group in sd */
+	struct sched_group *group_leader; /* Group which relieves group_min */
+	unsigned long min_load_per_task; /* load_per_task in group_min */
+	unsigned long leader_nr_running; /* Nr running of group_leader */
+	unsigned long min_nr_running; /* Nr running of group_min */
+#endif
+};
+
+/*
+ * sg_lb_stats - stats of a sched_group required for load_balancing
+ */
+struct sg_lb_stats {
+	unsigned long avg_load; /*Avg load across the CPUs of the group */
+	unsigned long group_load; /* Total load over the CPUs of the group */
+	unsigned long sum_nr_running; /* Nr tasks running in the group */
+	unsigned long sum_weighted_load; /* Weighted load of group's tasks */
+	unsigned long group_capacity;
+	unsigned long idle_cpus;
+	unsigned long group_weight;
+	int group_imb; /* Is there an imbalance in the group ? */
+	int group_has_capacity; /* Is there extra capacity in the group? */
+};
+
+/**
+ * get_sd_load_idx - Obtain the load index for a given sched domain.
+ * @sd: The sched_domain whose load_idx is to be obtained.
+ * @idle: The Idle status of the CPU for whose sd load_icx is obtained.
+ */
+static inline int get_sd_load_idx(struct sched_domain *sd,
+					enum cpu_idle_type idle)
+{
+	int load_idx;
+
+	switch (idle) {
+	case CPU_NOT_IDLE:
+		load_idx = sd->busy_idx;
+		break;
+
+	case CPU_NEWLY_IDLE:
+		load_idx = sd->newidle_idx;
+		break;
+	default:
+		load_idx = sd->idle_idx;
+		break;
+	}
+
+	return load_idx;
+}
+
+
+#if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT)
+/**
+ * init_sd_power_savings_stats - Initialize power savings statistics for
+ * the given sched_domain, during load balancing.
+ *
+ * @sd: Sched domain whose power-savings statistics are to be initialized.
+ * @sds: Variable containing the statistics for sd.
+ * @idle: Idle status of the CPU at which we're performing load-balancing.
+ */
+static inline void init_sd_power_savings_stats(struct sched_domain *sd,
+	struct sd_lb_stats *sds, enum cpu_idle_type idle)
+{
+	/*
+	 * Busy processors will not participate in power savings
+	 * balance.
+	 */
+	if (idle == CPU_NOT_IDLE || !(sd->flags & SD_POWERSAVINGS_BALANCE))
+		sds->power_savings_balance = 0;
+	else {
+		sds->power_savings_balance = 1;
+		sds->min_nr_running = ULONG_MAX;
+		sds->leader_nr_running = 0;
+	}
+}
+
+/**
+ * update_sd_power_savings_stats - Update the power saving stats for a
+ * sched_domain while performing load balancing.
+ *
+ * @group: sched_group belonging to the sched_domain under consideration.
+ * @sds: Variable containing the statistics of the sched_domain
+ * @local_group: Does group contain the CPU for which we're performing
+ * 		load balancing ?
+ * @sgs: Variable containing the statistics of the group.
+ */
+static inline void update_sd_power_savings_stats(struct sched_group *group,
+	struct sd_lb_stats *sds, int local_group, struct sg_lb_stats *sgs)
+{
+
+	if (!sds->power_savings_balance)
+		return;
+
+	/*
+	 * If the local group is idle or completely loaded
+	 * no need to do power savings balance at this domain
+	 */
+	if (local_group && (sds->this_nr_running >= sgs->group_capacity ||
+				!sds->this_nr_running))
+		sds->power_savings_balance = 0;
+
+	/*
+	 * If a group is already running at full capacity or idle,
+	 * don't include that group in power savings calculations
+	 */
+	if (!sds->power_savings_balance ||
+		sgs->sum_nr_running >= sgs->group_capacity ||
+		!sgs->sum_nr_running)
+		return;
+
+	/*
+	 * Calculate the group which has the least non-idle load.
+	 * This is the group from where we need to pick up the load
+	 * for saving power
+	 */
+	if ((sgs->sum_nr_running < sds->min_nr_running) ||
+	    (sgs->sum_nr_running == sds->min_nr_running &&
+	     group_first_cpu(group) > group_first_cpu(sds->group_min))) {
+		sds->group_min = group;
+		sds->min_nr_running = sgs->sum_nr_running;
+		sds->min_load_per_task = sgs->sum_weighted_load /
+						sgs->sum_nr_running;
+	}
+
+	/*
+	 * Calculate the group which is almost near its
+	 * capacity but still has some space to pick up some load
+	 * from other group and save more power
+	 */
+	if (sgs->sum_nr_running + 1 > sgs->group_capacity)
+		return;
+
+	if (sgs->sum_nr_running > sds->leader_nr_running ||
+	    (sgs->sum_nr_running == sds->leader_nr_running &&
+	     group_first_cpu(group) < group_first_cpu(sds->group_leader))) {
+		sds->group_leader = group;
+		sds->leader_nr_running = sgs->sum_nr_running;
+	}
+}
+
+/**
+ * check_power_save_busiest_group - see if there is potential for some power-savings balance
+ * @sds: Variable containing the statistics of the sched_domain
+ *	under consideration.
+ * @this_cpu: Cpu at which we're currently performing load-balancing.
+ * @imbalance: Variable to store the imbalance.
+ *
+ * Description:
+ * Check if we have potential to perform some power-savings balance.
+ * If yes, set the busiest group to be the least loaded group in the
+ * sched_domain, so that it's CPUs can be put to idle.
+ *
+ * Returns 1 if there is potential to perform power-savings balance.
+ * Else returns 0.
+ */
+static inline int check_power_save_busiest_group(struct sd_lb_stats *sds,
+					int this_cpu, unsigned long *imbalance)
+{
+	if (!sds->power_savings_balance)
+		return 0;
+
+	if (sds->this != sds->group_leader ||
+			sds->group_leader == sds->group_min)
+		return 0;
+
+	*imbalance = sds->min_load_per_task;
+	sds->busiest = sds->group_min;
+
+	return 1;
+
+}
+#else /* CONFIG_SCHED_MC || CONFIG_SCHED_SMT */
+static inline void init_sd_power_savings_stats(struct sched_domain *sd,
+	struct sd_lb_stats *sds, enum cpu_idle_type idle)
+{
+	return;
+}
+
+static inline void update_sd_power_savings_stats(struct sched_group *group,
+	struct sd_lb_stats *sds, int local_group, struct sg_lb_stats *sgs)
+{
+	return;
+}
+
+static inline int check_power_save_busiest_group(struct sd_lb_stats *sds,
+					int this_cpu, unsigned long *imbalance)
+{
+	return 0;
+}
+#endif /* CONFIG_SCHED_MC || CONFIG_SCHED_SMT */
+
+
+unsigned long default_scale_freq_power(struct sched_domain *sd, int cpu)
+{
+	return SCHED_POWER_SCALE;
+}
+
+unsigned long __weak arch_scale_freq_power(struct sched_domain *sd, int cpu)
+{
+	return default_scale_freq_power(sd, cpu);
+}
+
+unsigned long default_scale_smt_power(struct sched_domain *sd, int cpu)
+{
+	unsigned long weight = sd->span_weight;
+	unsigned long smt_gain = sd->smt_gain;
+
+	smt_gain /= weight;
+
+	return smt_gain;
+}
+
+unsigned long __weak arch_scale_smt_power(struct sched_domain *sd, int cpu)
+{
+	return default_scale_smt_power(sd, cpu);
+}
+
+unsigned long scale_rt_power(int cpu)
+{
+	struct rq *rq = cpu_rq(cpu);
+	u64 total, available;
+
+	total = sched_avg_period() + (rq->clock - rq->age_stamp);
+
+	if (unlikely(total < rq->rt_avg)) {
+		/* Ensures that power won't end up being negative */
+		available = 0;
+	} else {
+		available = total - rq->rt_avg;
+	}
+
+	if (unlikely((s64)total < SCHED_POWER_SCALE))
+		total = SCHED_POWER_SCALE;
+
+	total >>= SCHED_POWER_SHIFT;
+
+	return div_u64(available, total);
+}
+
+static void update_cpu_power(struct sched_domain *sd, int cpu)
+{
+	unsigned long weight = sd->span_weight;
+	unsigned long power = SCHED_POWER_SCALE;
+	struct sched_group *sdg = sd->groups;
+
+	if ((sd->flags & SD_SHARE_CPUPOWER) && weight > 1) {
+		if (sched_feat(ARCH_POWER))
+			power *= arch_scale_smt_power(sd, cpu);
+		else
+			power *= default_scale_smt_power(sd, cpu);
+
+		power >>= SCHED_POWER_SHIFT;
+	}
+
+	sdg->sgp->power_orig = power;
+
+	if (sched_feat(ARCH_POWER))
+		power *= arch_scale_freq_power(sd, cpu);
+	else
+		power *= default_scale_freq_power(sd, cpu);
+
+	power >>= SCHED_POWER_SHIFT;
+
+	power *= scale_rt_power(cpu);
+	power >>= SCHED_POWER_SHIFT;
+
+	if (!power)
+		power = 1;
+
+	cpu_rq(cpu)->cpu_power = power;
+	sdg->sgp->power = power;
+}
+
+void update_group_power(struct sched_domain *sd, int cpu)
+{
+	struct sched_domain *child = sd->child;
+	struct sched_group *group, *sdg = sd->groups;
+	unsigned long power;
+
+	if (!child) {
+		update_cpu_power(sd, cpu);
+		return;
+	}
+
+	power = 0;
+
+	group = child->groups;
+	do {
+		power += group->sgp->power;
+		group = group->next;
+	} while (group != child->groups);
+
+	sdg->sgp->power = power;
+}
+
+/*
+ * Try and fix up capacity for tiny siblings, this is needed when
+ * things like SD_ASYM_PACKING need f_b_g to select another sibling
+ * which on its own isn't powerful enough.
+ *
+ * See update_sd_pick_busiest() and check_asym_packing().
+ */
+static inline int
+fix_small_capacity(struct sched_domain *sd, struct sched_group *group)
+{
+	/*
+	 * Only siblings can have significantly less than SCHED_POWER_SCALE
+	 */
+	if (!(sd->flags & SD_SHARE_CPUPOWER))
+		return 0;
+
+	/*
+	 * If ~90% of the cpu_power is still there, we're good.
+	 */
+	if (group->sgp->power * 32 > group->sgp->power_orig * 29)
+		return 1;
+
+	return 0;
+}
+
+/**
+ * update_sg_lb_stats - Update sched_group's statistics for load balancing.
+ * @sd: The sched_domain whose statistics are to be updated.
+ * @group: sched_group whose statistics are to be updated.
+ * @this_cpu: Cpu for which load balance is currently performed.
+ * @idle: Idle status of this_cpu
+ * @load_idx: Load index of sched_domain of this_cpu for load calc.
+ * @local_group: Does group contain this_cpu.
+ * @cpus: Set of cpus considered for load balancing.
+ * @balance: Should we balance.
+ * @sgs: variable to hold the statistics for this group.
+ */
+static inline void update_sg_lb_stats(struct sched_domain *sd,
+			struct sched_group *group, int this_cpu,
+			enum cpu_idle_type idle, int load_idx,
+			int local_group, const struct cpumask *cpus,
+			int *balance, struct sg_lb_stats *sgs)
+{
+	unsigned long load, max_cpu_load, min_cpu_load, max_nr_running;
+	int i;
+	unsigned int balance_cpu = -1, first_idle_cpu = 0;
+	unsigned long avg_load_per_task = 0;
+
+	if (local_group)
+		balance_cpu = group_first_cpu(group);
+
+	/* Tally up the load of all CPUs in the group */
+	max_cpu_load = 0;
+	min_cpu_load = ~0UL;
+	max_nr_running = 0;
+
+	for_each_cpu_and(i, sched_group_cpus(group), cpus) {
+		struct rq *rq = cpu_rq(i);
+
+		/* Bias balancing toward cpus of our domain */
+		if (local_group) {
+			if (idle_cpu(i) && !first_idle_cpu) {
+				first_idle_cpu = 1;
+				balance_cpu = i;
+			}
+
+			load = target_load(i, load_idx);
+		} else {
+			load = source_load(i, load_idx);
+			if (load > max_cpu_load) {
+				max_cpu_load = load;
+				max_nr_running = rq->nr_running;
+			}
+			if (min_cpu_load > load)
+				min_cpu_load = load;
+		}
+
+		sgs->group_load += load;
+		sgs->sum_nr_running += rq->nr_running;
+		sgs->sum_weighted_load += weighted_cpuload(i);
+		if (idle_cpu(i))
+			sgs->idle_cpus++;
+	}
+
+	/*
+	 * First idle cpu or the first cpu(busiest) in this sched group
+	 * is eligible for doing load balancing at this and above
+	 * domains. In the newly idle case, we will allow all the cpu's
+	 * to do the newly idle load balance.
+	 */
+	if (idle != CPU_NEWLY_IDLE && local_group) {
+		if (balance_cpu != this_cpu) {
+			*balance = 0;
+			return;
+		}
+		update_group_power(sd, this_cpu);
+	}
+
+	/* Adjust by relative CPU power of the group */
+	sgs->avg_load = (sgs->group_load*SCHED_POWER_SCALE) / group->sgp->power;
+
+	/*
+	 * Consider the group unbalanced when the imbalance is larger
+	 * than the average weight of a task.
+	 *
+	 * APZ: with cgroup the avg task weight can vary wildly and
+	 *      might not be a suitable number - should we keep a
+	 *      normalized nr_running number somewhere that negates
+	 *      the hierarchy?
+	 */
+	if (sgs->sum_nr_running)
+		avg_load_per_task = sgs->sum_weighted_load / sgs->sum_nr_running;
+
+	if ((max_cpu_load - min_cpu_load) >= avg_load_per_task && max_nr_running > 1)
+		sgs->group_imb = 1;
+
+	sgs->group_capacity = DIV_ROUND_CLOSEST(group->sgp->power,
+						SCHED_POWER_SCALE);
+	if (!sgs->group_capacity)
+		sgs->group_capacity = fix_small_capacity(sd, group);
+	sgs->group_weight = group->group_weight;
+
+	if (sgs->group_capacity > sgs->sum_nr_running)
+		sgs->group_has_capacity = 1;
+}
+
+/**
+ * update_sd_pick_busiest - return 1 on busiest group
+ * @sd: sched_domain whose statistics are to be checked
+ * @sds: sched_domain statistics
+ * @sg: sched_group candidate to be checked for being the busiest
+ * @sgs: sched_group statistics
+ * @this_cpu: the current cpu
+ *
+ * Determine if @sg is a busier group than the previously selected
+ * busiest group.
+ */
+static bool update_sd_pick_busiest(struct sched_domain *sd,
+				   struct sd_lb_stats *sds,
+				   struct sched_group *sg,
+				   struct sg_lb_stats *sgs,
+				   int this_cpu)
+{
+	if (sgs->avg_load <= sds->max_load)
+		return false;
+
+	if (sgs->sum_nr_running > sgs->group_capacity)
+		return true;
+
+	if (sgs->group_imb)
+		return true;
+
+	/*
+	 * ASYM_PACKING needs to move all the work to the lowest
+	 * numbered CPUs in the group, therefore mark all groups
+	 * higher than ourself as busy.
+	 */
+	if ((sd->flags & SD_ASYM_PACKING) && sgs->sum_nr_running &&
+	    this_cpu < group_first_cpu(sg)) {
+		if (!sds->busiest)
+			return true;
+
+		if (group_first_cpu(sds->busiest) > group_first_cpu(sg))
+			return true;
+	}
+
+	return false;
+}
+
+/**
+ * update_sd_lb_stats - Update sched_domain's statistics for load balancing.
+ * @sd: sched_domain whose statistics are to be updated.
+ * @this_cpu: Cpu for which load balance is currently performed.
+ * @idle: Idle status of this_cpu
+ * @cpus: Set of cpus considered for load balancing.
+ * @balance: Should we balance.
+ * @sds: variable to hold the statistics for this sched_domain.
+ */
+static inline void update_sd_lb_stats(struct sched_domain *sd, int this_cpu,
+			enum cpu_idle_type idle, const struct cpumask *cpus,
+			int *balance, struct sd_lb_stats *sds)
+{
+	struct sched_domain *child = sd->child;
+	struct sched_group *sg = sd->groups;
+	struct sg_lb_stats sgs;
+	int load_idx, prefer_sibling = 0;
+
+	if (child && child->flags & SD_PREFER_SIBLING)
+		prefer_sibling = 1;
+
+	init_sd_power_savings_stats(sd, sds, idle);
+	load_idx = get_sd_load_idx(sd, idle);
+
+	do {
+		int local_group;
+
+		local_group = cpumask_test_cpu(this_cpu, sched_group_cpus(sg));
+		memset(&sgs, 0, sizeof(sgs));
+		update_sg_lb_stats(sd, sg, this_cpu, idle, load_idx,
+				local_group, cpus, balance, &sgs);
+
+		if (local_group && !(*balance))
+			return;
+
+		sds->total_load += sgs.group_load;
+		sds->total_pwr += sg->sgp->power;
+
+		/*
+		 * In case the child domain prefers tasks go to siblings
+		 * first, lower the sg capacity to one so that we'll try
+		 * and move all the excess tasks away. We lower the capacity
+		 * of a group only if the local group has the capacity to fit
+		 * these excess tasks, i.e. nr_running < group_capacity. The
+		 * extra check prevents the case where you always pull from the
+		 * heaviest group when it is already under-utilized (possible
+		 * with a large weight task outweighs the tasks on the system).
+		 */
+		if (prefer_sibling && !local_group && sds->this_has_capacity)
+			sgs.group_capacity = min(sgs.group_capacity, 1UL);
+
+		if (local_group) {
+			sds->this_load = sgs.avg_load;
+			sds->this = sg;
+			sds->this_nr_running = sgs.sum_nr_running;
+			sds->this_load_per_task = sgs.sum_weighted_load;
+			sds->this_has_capacity = sgs.group_has_capacity;
+			sds->this_idle_cpus = sgs.idle_cpus;
+		} else if (update_sd_pick_busiest(sd, sds, sg, &sgs, this_cpu)) {
+			sds->max_load = sgs.avg_load;
+			sds->busiest = sg;
+			sds->busiest_nr_running = sgs.sum_nr_running;
+			sds->busiest_idle_cpus = sgs.idle_cpus;
+			sds->busiest_group_capacity = sgs.group_capacity;
+			sds->busiest_load_per_task = sgs.sum_weighted_load;
+			sds->busiest_has_capacity = sgs.group_has_capacity;
+			sds->busiest_group_weight = sgs.group_weight;
+			sds->group_imb = sgs.group_imb;
+		}
+
+		update_sd_power_savings_stats(sg, sds, local_group, &sgs);
+		sg = sg->next;
+	} while (sg != sd->groups);
+}
+
+/**
+ * check_asym_packing - Check to see if the group is packed into the
+ *			sched doman.
+ *
+ * This is primarily intended to used at the sibling level.  Some
+ * cores like POWER7 prefer to use lower numbered SMT threads.  In the
+ * case of POWER7, it can move to lower SMT modes only when higher
+ * threads are idle.  When in lower SMT modes, the threads will
+ * perform better since they share less core resources.  Hence when we
+ * have idle threads, we want them to be the higher ones.
+ *
+ * This packing function is run on idle threads.  It checks to see if
+ * the busiest CPU in this domain (core in the P7 case) has a higher
+ * CPU number than the packing function is being run on.  Here we are
+ * assuming lower CPU number will be equivalent to lower a SMT thread
+ * number.
+ *
+ * Returns 1 when packing is required and a task should be moved to
+ * this CPU.  The amount of the imbalance is returned in *imbalance.
+ *
+ * @sd: The sched_domain whose packing is to be checked.
+ * @sds: Statistics of the sched_domain which is to be packed
+ * @this_cpu: The cpu at whose sched_domain we're performing load-balance.
+ * @imbalance: returns amount of imbalanced due to packing.
+ */
+static int check_asym_packing(struct sched_domain *sd,
+			      struct sd_lb_stats *sds,
+			      int this_cpu, unsigned long *imbalance)
+{
+	int busiest_cpu;
+
+	if (!(sd->flags & SD_ASYM_PACKING))
+		return 0;
+
+	if (!sds->busiest)
+		return 0;
+
+	busiest_cpu = group_first_cpu(sds->busiest);
+	if (this_cpu > busiest_cpu)
+		return 0;
+
+	*imbalance = DIV_ROUND_CLOSEST(sds->max_load * sds->busiest->sgp->power,
+				       SCHED_POWER_SCALE);
+	return 1;
+}
+
+/**
+ * fix_small_imbalance - Calculate the minor imbalance that exists
+ *			amongst the groups of a sched_domain, during
+ *			load balancing.
+ * @sds: Statistics of the sched_domain whose imbalance is to be calculated.
+ * @this_cpu: The cpu at whose sched_domain we're performing load-balance.
+ * @imbalance: Variable to store the imbalance.
+ */
+static inline void fix_small_imbalance(struct sd_lb_stats *sds,
+				int this_cpu, unsigned long *imbalance)
+{
+	unsigned long tmp, pwr_now = 0, pwr_move = 0;
+	unsigned int imbn = 2;
+	unsigned long scaled_busy_load_per_task;
+
+	if (sds->this_nr_running) {
+		sds->this_load_per_task /= sds->this_nr_running;
+		if (sds->busiest_load_per_task >
+				sds->this_load_per_task)
+			imbn = 1;
+	} else
+		sds->this_load_per_task =
+			cpu_avg_load_per_task(this_cpu);
+
+	scaled_busy_load_per_task = sds->busiest_load_per_task
+					 * SCHED_POWER_SCALE;
+	scaled_busy_load_per_task /= sds->busiest->sgp->power;
+
+	if (sds->max_load - sds->this_load + scaled_busy_load_per_task >=
+			(scaled_busy_load_per_task * imbn)) {
+		*imbalance = sds->busiest_load_per_task;
+		return;
+	}
+
+	/*
+	 * OK, we don't have enough imbalance to justify moving tasks,
+	 * however we may be able to increase total CPU power used by
+	 * moving them.
+	 */
+
+	pwr_now += sds->busiest->sgp->power *
+			min(sds->busiest_load_per_task, sds->max_load);
+	pwr_now += sds->this->sgp->power *
+			min(sds->this_load_per_task, sds->this_load);
+	pwr_now /= SCHED_POWER_SCALE;
+
+	/* Amount of load we'd subtract */
+	tmp = (sds->busiest_load_per_task * SCHED_POWER_SCALE) /
+		sds->busiest->sgp->power;
+	if (sds->max_load > tmp)
+		pwr_move += sds->busiest->sgp->power *
+			min(sds->busiest_load_per_task, sds->max_load - tmp);
+
+	/* Amount of load we'd add */
+	if (sds->max_load * sds->busiest->sgp->power <
+		sds->busiest_load_per_task * SCHED_POWER_SCALE)
+		tmp = (sds->max_load * sds->busiest->sgp->power) /
+			sds->this->sgp->power;
+	else
+		tmp = (sds->busiest_load_per_task * SCHED_POWER_SCALE) /
+			sds->this->sgp->power;
+	pwr_move += sds->this->sgp->power *
+			min(sds->this_load_per_task, sds->this_load + tmp);
+	pwr_move /= SCHED_POWER_SCALE;
+
+	/* Move if we gain throughput */
+	if (pwr_move > pwr_now)
+		*imbalance = sds->busiest_load_per_task;
+}
+
+/**
+ * calculate_imbalance - Calculate the amount of imbalance present within the
+ *			 groups of a given sched_domain during load balance.
+ * @sds: statistics of the sched_domain whose imbalance is to be calculated.
+ * @this_cpu: Cpu for which currently load balance is being performed.
+ * @imbalance: The variable to store the imbalance.
+ */
+static inline void calculate_imbalance(struct sd_lb_stats *sds, int this_cpu,
+		unsigned long *imbalance)
+{
+	unsigned long max_pull, load_above_capacity = ~0UL;
+
+	sds->busiest_load_per_task /= sds->busiest_nr_running;
+	if (sds->group_imb) {
+		sds->busiest_load_per_task =
+			min(sds->busiest_load_per_task, sds->avg_load);
+	}
+
+	/*
+	 * In the presence of smp nice balancing, certain scenarios can have
+	 * max load less than avg load(as we skip the groups at or below
+	 * its cpu_power, while calculating max_load..)
+	 */
+	if (sds->max_load < sds->avg_load) {
+		*imbalance = 0;
+		return fix_small_imbalance(sds, this_cpu, imbalance);
+	}
+
+	if (!sds->group_imb) {
+		/*
+		 * Don't want to pull so many tasks that a group would go idle.
+		 */
+		load_above_capacity = (sds->busiest_nr_running -
+						sds->busiest_group_capacity);
+
+		load_above_capacity *= (SCHED_LOAD_SCALE * SCHED_POWER_SCALE);
+
+		load_above_capacity /= sds->busiest->sgp->power;
+	}
+
+	/*
+	 * We're trying to get all the cpus to the average_load, so we don't
+	 * want to push ourselves above the average load, nor do we wish to
+	 * reduce the max loaded cpu below the average load. At the same time,
+	 * we also don't want to reduce the group load below the group capacity
+	 * (so that we can implement power-savings policies etc). Thus we look
+	 * for the minimum possible imbalance.
+	 * Be careful of negative numbers as they'll appear as very large values
+	 * with unsigned longs.
+	 */
+	max_pull = min(sds->max_load - sds->avg_load, load_above_capacity);
+
+	/* How much load to actually move to equalise the imbalance */
+	*imbalance = min(max_pull * sds->busiest->sgp->power,
+		(sds->avg_load - sds->this_load) * sds->this->sgp->power)
+			/ SCHED_POWER_SCALE;
+
+	/*
+	 * if *imbalance is less than the average load per runnable task
+	 * there is no guarantee that any tasks will be moved so we'll have
+	 * a think about bumping its value to force at least one task to be
+	 * moved
+	 */
+	if (*imbalance < sds->busiest_load_per_task)
+		return fix_small_imbalance(sds, this_cpu, imbalance);
+
+}
+
+/******* find_busiest_group() helpers end here *********************/
+
+/**
+ * find_busiest_group - Returns the busiest group within the sched_domain
+ * if there is an imbalance. If there isn't an imbalance, and
+ * the user has opted for power-savings, it returns a group whose
+ * CPUs can be put to idle by rebalancing those tasks elsewhere, if
+ * such a group exists.
+ *
+ * Also calculates the amount of weighted load which should be moved
+ * to restore balance.
+ *
+ * @sd: The sched_domain whose busiest group is to be returned.
+ * @this_cpu: The cpu for which load balancing is currently being performed.
+ * @imbalance: Variable which stores amount of weighted load which should
+ *		be moved to restore balance/put a group to idle.
+ * @idle: The idle status of this_cpu.
+ * @cpus: The set of CPUs under consideration for load-balancing.
+ * @balance: Pointer to a variable indicating if this_cpu
+ *	is the appropriate cpu to perform load balancing at this_level.
+ *
+ * Returns:	- the busiest group if imbalance exists.
+ *		- If no imbalance and user has opted for power-savings balance,
+ *		   return the least loaded group whose CPUs can be
+ *		   put to idle by rebalancing its tasks onto our group.
+ */
+static struct sched_group *
+find_busiest_group(struct sched_domain *sd, int this_cpu,
+		   unsigned long *imbalance, enum cpu_idle_type idle,
+		   const struct cpumask *cpus, int *balance)
+{
+	struct sd_lb_stats sds;
+
+	memset(&sds, 0, sizeof(sds));
+
+	/*
+	 * Compute the various statistics relavent for load balancing at
+	 * this level.
+	 */
+	update_sd_lb_stats(sd, this_cpu, idle, cpus, balance, &sds);
+
+	/*
+	 * this_cpu is not the appropriate cpu to perform load balancing at
+	 * this level.
+	 */
+	if (!(*balance))
+		goto ret;
+
+	if ((idle == CPU_IDLE || idle == CPU_NEWLY_IDLE) &&
+	    check_asym_packing(sd, &sds, this_cpu, imbalance))
+		return sds.busiest;
+
+	/* There is no busy sibling group to pull tasks from */
+	if (!sds.busiest || sds.busiest_nr_running == 0)
+		goto out_balanced;
+
+	sds.avg_load = (SCHED_POWER_SCALE * sds.total_load) / sds.total_pwr;
+
+	/*
+	 * If the busiest group is imbalanced the below checks don't
+	 * work because they assumes all things are equal, which typically
+	 * isn't true due to cpus_allowed constraints and the like.
+	 */
+	if (sds.group_imb)
+		goto force_balance;
+
+	/* SD_BALANCE_NEWIDLE trumps SMP nice when underutilized */
+	if (idle == CPU_NEWLY_IDLE && sds.this_has_capacity &&
+			!sds.busiest_has_capacity)
+		goto force_balance;
+
+	/*
+	 * If the local group is more busy than the selected busiest group
+	 * don't try and pull any tasks.
+	 */
+	if (sds.this_load >= sds.max_load)
+		goto out_balanced;
+
+	/*
+	 * Don't pull any tasks if this group is already above the domain
+	 * average load.
+	 */
+	if (sds.this_load >= sds.avg_load)
+		goto out_balanced;
+
+	if (idle == CPU_IDLE) {
+		/*
+		 * This cpu is idle. If the busiest group load doesn't
+		 * have more tasks than the number of available cpu's and
+		 * there is no imbalance between this and busiest group
+		 * wrt to idle cpu's, it is balanced.
+		 */
+		if ((sds.this_idle_cpus <= sds.busiest_idle_cpus + 1) &&
+		    sds.busiest_nr_running <= sds.busiest_group_weight)
+			goto out_balanced;
+	} else {
+		/*
+		 * In the CPU_NEWLY_IDLE, CPU_NOT_IDLE cases, use
+		 * imbalance_pct to be conservative.
+		 */
+		if (100 * sds.max_load <= sd->imbalance_pct * sds.this_load)
+			goto out_balanced;
+	}
+
+force_balance:
+	/* Looks like there is an imbalance. Compute it */
+	calculate_imbalance(&sds, this_cpu, imbalance);
+	return sds.busiest;
+
+out_balanced:
+	/*
+	 * There is no obvious imbalance. But check if we can do some balancing
+	 * to save power.
+	 */
+	if (check_power_save_busiest_group(&sds, this_cpu, imbalance))
+		return sds.busiest;
+ret:
+	*imbalance = 0;
+	return NULL;
+}
+
+/*
+ * find_busiest_queue - find the busiest runqueue among the cpus in group.
+ */
+static struct rq *
+find_busiest_queue(struct sched_domain *sd, struct sched_group *group,
+		   enum cpu_idle_type idle, unsigned long imbalance,
+		   const struct cpumask *cpus)
+{
+	struct rq *busiest = NULL, *rq;
+	unsigned long max_load = 0;
+	int i;
+
+	for_each_cpu(i, sched_group_cpus(group)) {
+		unsigned long power = power_of(i);
+		unsigned long capacity = DIV_ROUND_CLOSEST(power,
+							   SCHED_POWER_SCALE);
+		unsigned long wl;
+
+		if (!capacity)
+			capacity = fix_small_capacity(sd, group);
+
+		if (!cpumask_test_cpu(i, cpus))
+			continue;
+
+		rq = cpu_rq(i);
+		wl = weighted_cpuload(i);
+
+		/*
+		 * When comparing with imbalance, use weighted_cpuload()
+		 * which is not scaled with the cpu power.
+		 */
+		if (capacity && rq->nr_running == 1 && wl > imbalance)
+			continue;
+
+		/*
+		 * For the load comparisons with the other cpu's, consider
+		 * the weighted_cpuload() scaled with the cpu power, so that
+		 * the load can be moved away from the cpu that is potentially
+		 * running at a lower capacity.
+		 */
+		wl = (wl * SCHED_POWER_SCALE) / power;
+
+		if (wl > max_load) {
+			max_load = wl;
+			busiest = rq;
+		}
+	}
+
+	return busiest;
+}
+
+/*
+ * Max backoff if we encounter pinned tasks. Pretty arbitrary value, but
+ * so long as it is large enough.
+ */
+#define MAX_PINNED_INTERVAL	512
+
+/* Working cpumask for load_balance and load_balance_newidle. */
+DEFINE_PER_CPU(cpumask_var_t, load_balance_tmpmask);
+
+static int need_active_balance(struct sched_domain *sd, int idle,
+			       int busiest_cpu, int this_cpu)
+{
+	if (idle == CPU_NEWLY_IDLE) {
+
+		/*
+		 * ASYM_PACKING needs to force migrate tasks from busy but
+		 * higher numbered CPUs in order to pack all tasks in the
+		 * lowest numbered CPUs.
+		 */
+		if ((sd->flags & SD_ASYM_PACKING) && busiest_cpu > this_cpu)
+			return 1;
+
+		/*
+		 * The only task running in a non-idle cpu can be moved to this
+		 * cpu in an attempt to completely freeup the other CPU
+		 * package.
+		 *
+		 * The package power saving logic comes from
+		 * find_busiest_group(). If there are no imbalance, then
+		 * f_b_g() will return NULL. However when sched_mc={1,2} then
+		 * f_b_g() will select a group from which a running task may be
+		 * pulled to this cpu in order to make the other package idle.
+		 * If there is no opportunity to make a package idle and if
+		 * there are no imbalance, then f_b_g() will return NULL and no
+		 * action will be taken in load_balance_newidle().
+		 *
+		 * Under normal task pull operation due to imbalance, there
+		 * will be more than one task in the source run queue and
+		 * move_tasks() will succeed.  ld_moved will be true and this
+		 * active balance code will not be triggered.
+		 */
+		if (sched_mc_power_savings < POWERSAVINGS_BALANCE_WAKEUP)
+			return 0;
+	}
+
+	return unlikely(sd->nr_balance_failed > sd->cache_nice_tries+2);
+}
+
+static int active_load_balance_cpu_stop(void *data);
+
+/*
+ * Check this_cpu to ensure it is balanced within domain. Attempt to move
+ * tasks if there is an imbalance.
+ */
+static int load_balance(int this_cpu, struct rq *this_rq,
+			struct sched_domain *sd, enum cpu_idle_type idle,
+			int *balance)
+{
+	int ld_moved, lb_flags = 0, active_balance = 0;
+	struct sched_group *group;
+	unsigned long imbalance;
+	struct rq *busiest;
+	unsigned long flags;
+	struct cpumask *cpus = __get_cpu_var(load_balance_tmpmask);
+
+	cpumask_copy(cpus, cpu_active_mask);
+
+	schedstat_inc(sd, lb_count[idle]);
+
+redo:
+	group = find_busiest_group(sd, this_cpu, &imbalance, idle,
+				   cpus, balance);
+
+	if (*balance == 0)
+		goto out_balanced;
+
+	if (!group) {
+		schedstat_inc(sd, lb_nobusyg[idle]);
+		goto out_balanced;
+	}
+
+	busiest = find_busiest_queue(sd, group, idle, imbalance, cpus);
+	if (!busiest) {
+		schedstat_inc(sd, lb_nobusyq[idle]);
+		goto out_balanced;
+	}
+
+	BUG_ON(busiest == this_rq);
+
+	schedstat_add(sd, lb_imbalance[idle], imbalance);
+
+	ld_moved = 0;
+	if (busiest->nr_running > 1) {
+		/*
+		 * Attempt to move tasks. If find_busiest_group has found
+		 * an imbalance but busiest->nr_running <= 1, the group is
+		 * still unbalanced. ld_moved simply stays zero, so it is
+		 * correctly treated as an imbalance.
+		 */
+		lb_flags |= LBF_ALL_PINNED;
+		local_irq_save(flags);
+		double_rq_lock(this_rq, busiest);
+		ld_moved = move_tasks(this_rq, this_cpu, busiest,
+				      imbalance, sd, idle, &lb_flags);
+		double_rq_unlock(this_rq, busiest);
+		local_irq_restore(flags);
+
+		/*
+		 * some other cpu did the load balance for us.
+		 */
+		if (ld_moved && this_cpu != smp_processor_id())
+			resched_cpu(this_cpu);
+
+		if (lb_flags & LBF_ABORT)
+			goto out_balanced;
+
+		if (lb_flags & LBF_NEED_BREAK) {
+			lb_flags += LBF_HAD_BREAK - LBF_NEED_BREAK;
+			if (lb_flags & LBF_ABORT)
+				goto out_balanced;
+			goto redo;
+		}
+
+		/* All tasks on this runqueue were pinned by CPU affinity */
+		if (unlikely(lb_flags & LBF_ALL_PINNED)) {
+			cpumask_clear_cpu(cpu_of(busiest), cpus);
+			if (!cpumask_empty(cpus))
+				goto redo;
+			goto out_balanced;
+		}
+	}
+
+	if (!ld_moved) {
+		schedstat_inc(sd, lb_failed[idle]);
+		/*
+		 * Increment the failure counter only on periodic balance.
+		 * We do not want newidle balance, which can be very
+		 * frequent, pollute the failure counter causing
+		 * excessive cache_hot migrations and active balances.
+		 */
+		if (idle != CPU_NEWLY_IDLE)
+			sd->nr_balance_failed++;
+
+		if (need_active_balance(sd, idle, cpu_of(busiest), this_cpu)) {
+			raw_spin_lock_irqsave(&busiest->lock, flags);
+
+			/* don't kick the active_load_balance_cpu_stop,
+			 * if the curr task on busiest cpu can't be
+			 * moved to this_cpu
+			 */
+			if (!cpumask_test_cpu(this_cpu,
+					tsk_cpus_allowed(busiest->curr))) {
+				raw_spin_unlock_irqrestore(&busiest->lock,
+							    flags);
+				lb_flags |= LBF_ALL_PINNED;
+				goto out_one_pinned;
+			}
+
+			/*
+			 * ->active_balance synchronizes accesses to
+			 * ->active_balance_work.  Once set, it's cleared
+			 * only after active load balance is finished.
+			 */
+			if (!busiest->active_balance) {
+				busiest->active_balance = 1;
+				busiest->push_cpu = this_cpu;
+				active_balance = 1;
+			}
+			raw_spin_unlock_irqrestore(&busiest->lock, flags);
+
+			if (active_balance)
+				stop_one_cpu_nowait(cpu_of(busiest),
+					active_load_balance_cpu_stop, busiest,
+					&busiest->active_balance_work);
+
+			/*
+			 * We've kicked active balancing, reset the failure
+			 * counter.
+			 */
+			sd->nr_balance_failed = sd->cache_nice_tries+1;
+		}
+	} else
+		sd->nr_balance_failed = 0;
+
+	if (likely(!active_balance)) {
+		/* We were unbalanced, so reset the balancing interval */
+		sd->balance_interval = sd->min_interval;
+	} else {
+		/*
+		 * If we've begun active balancing, start to back off. This
+		 * case may not be covered by the all_pinned logic if there
+		 * is only 1 task on the busy runqueue (because we don't call
+		 * move_tasks).
+		 */
+		if (sd->balance_interval < sd->max_interval)
+			sd->balance_interval *= 2;
+	}
+
+	goto out;
+
+out_balanced:
+	schedstat_inc(sd, lb_balanced[idle]);
+
+	sd->nr_balance_failed = 0;
+
+out_one_pinned:
+	/* tune up the balancing interval */
+	if (((lb_flags & LBF_ALL_PINNED) &&
+			sd->balance_interval < MAX_PINNED_INTERVAL) ||
+			(sd->balance_interval < sd->max_interval))
+		sd->balance_interval *= 2;
+
+	ld_moved = 0;
+out:
+	return ld_moved;
+}
+
+/*
+ * idle_balance is called by schedule() if this_cpu is about to become
+ * idle. Attempts to pull tasks from other CPUs.
+ */
+void idle_balance(int this_cpu, struct rq *this_rq)
+{
+	struct sched_domain *sd;
+	int pulled_task = 0;
+	unsigned long next_balance = jiffies + HZ;
+
+	this_rq->idle_stamp = this_rq->clock;
+
+	if (this_rq->avg_idle < sysctl_sched_migration_cost)
+		return;
+
+	/*
+	 * Drop the rq->lock, but keep IRQ/preempt disabled.
+	 */
+	raw_spin_unlock(&this_rq->lock);
+
+	update_shares(this_cpu);
+	rcu_read_lock();
+	for_each_domain(this_cpu, sd) {
+		unsigned long interval;
+		int balance = 1;
+
+		if (!(sd->flags & SD_LOAD_BALANCE))
+			continue;
+
+		if (sd->flags & SD_BALANCE_NEWIDLE) {
+			/* If we've pulled tasks over stop searching: */
+			pulled_task = load_balance(this_cpu, this_rq,
+						   sd, CPU_NEWLY_IDLE, &balance);
+		}
+
+		interval = msecs_to_jiffies(sd->balance_interval);
+		if (time_after(next_balance, sd->last_balance + interval))
+			next_balance = sd->last_balance + interval;
+		if (pulled_task) {
+			this_rq->idle_stamp = 0;
+			break;
+		}
+	}
+	rcu_read_unlock();
+
+	raw_spin_lock(&this_rq->lock);
+
+	if (pulled_task || time_after(jiffies, this_rq->next_balance)) {
+		/*
+		 * We are going idle. next_balance may be set based on
+		 * a busy processor. So reset next_balance.
+		 */
+		this_rq->next_balance = next_balance;
+	}
+}
+
+/*
+ * active_load_balance_cpu_stop is run by cpu stopper. It pushes
+ * running tasks off the busiest CPU onto idle CPUs. It requires at
+ * least 1 task to be running on each physical CPU where possible, and
+ * avoids physical / logical imbalances.
+ */
+static int active_load_balance_cpu_stop(void *data)
+{
+	struct rq *busiest_rq = data;
+	int busiest_cpu = cpu_of(busiest_rq);
+	int target_cpu = busiest_rq->push_cpu;
+	struct rq *target_rq = cpu_rq(target_cpu);
+	struct sched_domain *sd;
+
+	raw_spin_lock_irq(&busiest_rq->lock);
+
+	/* make sure the requested cpu hasn't gone down in the meantime */
+	if (unlikely(busiest_cpu != smp_processor_id() ||
+		     !busiest_rq->active_balance))
+		goto out_unlock;
+
+	/* Is there any task to move? */
+	if (busiest_rq->nr_running <= 1)
+		goto out_unlock;
+
+	/*
+	 * This condition is "impossible", if it occurs
+	 * we need to fix it. Originally reported by
+	 * Bjorn Helgaas on a 128-cpu setup.
+	 */
+	BUG_ON(busiest_rq == target_rq);
+
+	/* move a task from busiest_rq to target_rq */
+	double_lock_balance(busiest_rq, target_rq);
+
+	/* Search for an sd spanning us and the target CPU. */
+	rcu_read_lock();
+	for_each_domain(target_cpu, sd) {
+		if ((sd->flags & SD_LOAD_BALANCE) &&
+		    cpumask_test_cpu(busiest_cpu, sched_domain_span(sd)))
+				break;
+	}
+
+	if (likely(sd)) {
+		schedstat_inc(sd, alb_count);
+
+		if (move_one_task(target_rq, target_cpu, busiest_rq,
+				  sd, CPU_IDLE))
+			schedstat_inc(sd, alb_pushed);
+		else
+			schedstat_inc(sd, alb_failed);
+	}
+	rcu_read_unlock();
+	double_unlock_balance(busiest_rq, target_rq);
+out_unlock:
+	busiest_rq->active_balance = 0;
+	raw_spin_unlock_irq(&busiest_rq->lock);
+	return 0;
+}
+
+#ifdef CONFIG_NO_HZ
+/*
+ * idle load balancing details
+ * - When one of the busy CPUs notice that there may be an idle rebalancing
+ *   needed, they will kick the idle load balancer, which then does idle
+ *   load balancing for all the idle CPUs.
+ */
+static struct {
+	cpumask_var_t idle_cpus_mask;
+	atomic_t nr_cpus;
+	unsigned long next_balance;     /* in jiffy units */
+} nohz ____cacheline_aligned;
+
+#if defined(CONFIG_SCHED_MC) || defined(CONFIG_SCHED_SMT)
+/**
+ * lowest_flag_domain - Return lowest sched_domain containing flag.
+ * @cpu:	The cpu whose lowest level of sched domain is to
+ *		be returned.
+ * @flag:	The flag to check for the lowest sched_domain
+ *		for the given cpu.
+ *
+ * Returns the lowest sched_domain of a cpu which contains the given flag.
+ */
+static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
+{
+	struct sched_domain *sd;
+
+	for_each_domain(cpu, sd)
+		if (sd->flags & flag)
+			break;
+
+	return sd;
+}
+
+/**
+ * for_each_flag_domain - Iterates over sched_domains containing the flag.
+ * @cpu:	The cpu whose domains we're iterating over.
+ * @sd:		variable holding the value of the power_savings_sd
+ *		for cpu.
+ * @flag:	The flag to filter the sched_domains to be iterated.
+ *
+ * Iterates over all the scheduler domains for a given cpu that has the 'flag'
+ * set, starting from the lowest sched_domain to the highest.
+ */
+#define for_each_flag_domain(cpu, sd, flag) \
+	for (sd = lowest_flag_domain(cpu, flag); \
+		(sd && (sd->flags & flag)); sd = sd->parent)
+
+/**
+ * find_new_ilb - Finds the optimum idle load balancer for nomination.
+ * @cpu:	The cpu which is nominating a new idle_load_balancer.
+ *
+ * Returns:	Returns the id of the idle load balancer if it exists,
+ *		Else, returns >= nr_cpu_ids.
+ *
+ * This algorithm picks the idle load balancer such that it belongs to a
+ * semi-idle powersavings sched_domain. The idea is to try and avoid
+ * completely idle packages/cores just for the purpose of idle load balancing
+ * when there are other idle cpu's which are better suited for that job.
+ */
+static int find_new_ilb(int cpu)
+{
+	int ilb = cpumask_first(nohz.idle_cpus_mask);
+	struct sched_group *ilbg;
+	struct sched_domain *sd;
+
+	/*
+	 * Have idle load balancer selection from semi-idle packages only
+	 * when power-aware load balancing is enabled
+	 */
+	if (!(sched_smt_power_savings || sched_mc_power_savings))
+		goto out_done;
+
+	/*
+	 * Optimize for the case when we have no idle CPUs or only one
+	 * idle CPU. Don't walk the sched_domain hierarchy in such cases
+	 */
+	if (cpumask_weight(nohz.idle_cpus_mask) < 2)
+		goto out_done;
+
+	rcu_read_lock();
+	for_each_flag_domain(cpu, sd, SD_POWERSAVINGS_BALANCE) {
+		ilbg = sd->groups;
+
+		do {
+			if (ilbg->group_weight !=
+				atomic_read(&ilbg->sgp->nr_busy_cpus)) {
+				ilb = cpumask_first_and(nohz.idle_cpus_mask,
+							sched_group_cpus(ilbg));
+				goto unlock;
+			}
+
+			ilbg = ilbg->next;
+
+		} while (ilbg != sd->groups);
+	}
+unlock:
+	rcu_read_unlock();
+
+out_done:
+	if (ilb < nr_cpu_ids && idle_cpu(ilb))
+		return ilb;
+
+	return nr_cpu_ids;
+}
+#else /*  (CONFIG_SCHED_MC || CONFIG_SCHED_SMT) */
+static inline int find_new_ilb(int call_cpu)
+{
+	return nr_cpu_ids;
+}
+#endif
+
+/*
+ * Kick a CPU to do the nohz balancing, if it is time for it. We pick the
+ * nohz_load_balancer CPU (if there is one) otherwise fallback to any idle
+ * CPU (if there is one).
+ */
+static void nohz_balancer_kick(int cpu)
+{
+	int ilb_cpu;
+
+	nohz.next_balance++;
+
+	ilb_cpu = find_new_ilb(cpu);
+
+	if (ilb_cpu >= nr_cpu_ids)
+		return;
+
+	if (test_and_set_bit(NOHZ_BALANCE_KICK, nohz_flags(ilb_cpu)))
+		return;
+	/*
+	 * Use smp_send_reschedule() instead of resched_cpu().
+	 * This way we generate a sched IPI on the target cpu which
+	 * is idle. And the softirq performing nohz idle load balance
+	 * will be run before returning from the IPI.
+	 */
+	smp_send_reschedule(ilb_cpu);
+	return;
+}
+
+static inline void set_cpu_sd_state_busy(void)
+{
+	struct sched_domain *sd;
+	int cpu = smp_processor_id();
+
+	if (!test_bit(NOHZ_IDLE, nohz_flags(cpu)))
+		return;
+	clear_bit(NOHZ_IDLE, nohz_flags(cpu));
+
+	rcu_read_lock();
+	for_each_domain(cpu, sd)
+		atomic_inc(&sd->groups->sgp->nr_busy_cpus);
+	rcu_read_unlock();
+}
+
+void set_cpu_sd_state_idle(void)
+{
+	struct sched_domain *sd;
+	int cpu = smp_processor_id();
+
+	if (test_bit(NOHZ_IDLE, nohz_flags(cpu)))
+		return;
+	set_bit(NOHZ_IDLE, nohz_flags(cpu));
+
+	rcu_read_lock();
+	for_each_domain(cpu, sd)
+		atomic_dec(&sd->groups->sgp->nr_busy_cpus);
+	rcu_read_unlock();
+}
+
+/*
+ * This routine will record that this cpu is going idle with tick stopped.
+ * This info will be used in performing idle load balancing in the future.
+ */
+void select_nohz_load_balancer(int stop_tick)
+{
+	int cpu = smp_processor_id();
+
+	if (stop_tick) {
+		if (test_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu)))
+			return;
+
+		cpumask_set_cpu(cpu, nohz.idle_cpus_mask);
+		atomic_inc(&nohz.nr_cpus);
+		set_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu));
+	}
+	return;
+}
+#endif
+
+static DEFINE_SPINLOCK(balancing);
+
+static unsigned long __read_mostly max_load_balance_interval = HZ/10;
+
+/*
+ * Scale the max load_balance interval with the number of CPUs in the system.
+ * This trades load-balance latency on larger machines for less cross talk.
+ */
+void update_max_interval(void)
+{
+	max_load_balance_interval = HZ*num_online_cpus()/10;
+}
+
+/*
+ * It checks each scheduling domain to see if it is due to be balanced,
+ * and initiates a balancing operation if so.
+ *
+ * Balancing parameters are set up in arch_init_sched_domains.
+ */
+static void rebalance_domains(int cpu, enum cpu_idle_type idle)
+{
+	int balance = 1;
+	struct rq *rq = cpu_rq(cpu);
+	unsigned long interval;
+	struct sched_domain *sd;
+	/* Earliest time when we have to do rebalance again */
+	unsigned long next_balance = jiffies + 60*HZ;
+	int update_next_balance = 0;
+	int need_serialize;
+
+	update_shares(cpu);
+
+	rcu_read_lock();
+	for_each_domain(cpu, sd) {
+		if (!(sd->flags & SD_LOAD_BALANCE))
+			continue;
+
+		interval = sd->balance_interval;
+		if (idle != CPU_IDLE)
+			interval *= sd->busy_factor;
+
+		/* scale ms to jiffies */
+		interval = msecs_to_jiffies(interval);
+		interval = clamp(interval, 1UL, max_load_balance_interval);
+
+		need_serialize = sd->flags & SD_SERIALIZE;
+
+		if (need_serialize) {
+			if (!spin_trylock(&balancing))
+				goto out;
+		}
+
+		if (time_after_eq(jiffies, sd->last_balance + interval)) {
+			if (load_balance(cpu, rq, sd, idle, &balance)) {
+				/*
+				 * We've pulled tasks over so either we're no
+				 * longer idle.
+				 */
+				idle = CPU_NOT_IDLE;
+			}
+			sd->last_balance = jiffies;
+		}
+		if (need_serialize)
+			spin_unlock(&balancing);
+out:
+		if (time_after(next_balance, sd->last_balance + interval)) {
+			next_balance = sd->last_balance + interval;
+			update_next_balance = 1;
+		}
+
+		/*
+		 * Stop the load balance at this level. There is another
+		 * CPU in our sched group which is doing load balancing more
+		 * actively.
+		 */
+		if (!balance)
+			break;
+	}
+	rcu_read_unlock();
+
+	/*
+	 * next_balance will be updated only when there is a need.
+	 * When the cpu is attached to null domain for ex, it will not be
+	 * updated.
+	 */
+	if (likely(update_next_balance))
+		rq->next_balance = next_balance;
+}
+
+#ifdef CONFIG_NO_HZ
+/*
+ * In CONFIG_NO_HZ case, the idle balance kickee will do the
+ * rebalancing for all the cpus for whom scheduler ticks are stopped.
+ */
+static void nohz_idle_balance(int this_cpu, enum cpu_idle_type idle)
+{
+	struct rq *this_rq = cpu_rq(this_cpu);
+	struct rq *rq;
+	int balance_cpu;
+
+	if (idle != CPU_IDLE ||
+	    !test_bit(NOHZ_BALANCE_KICK, nohz_flags(this_cpu)))
+		goto end;
+
+	for_each_cpu(balance_cpu, nohz.idle_cpus_mask) {
+		if (balance_cpu == this_cpu || !idle_cpu(balance_cpu))
+			continue;
+
+		/*
+		 * If this cpu gets work to do, stop the load balancing
+		 * work being done for other cpus. Next load
+		 * balancing owner will pick it up.
+		 */
+		if (need_resched())
+			break;
+
+		raw_spin_lock_irq(&this_rq->lock);
+		update_rq_clock(this_rq);
+		update_cpu_load(this_rq);
+		raw_spin_unlock_irq(&this_rq->lock);
+
+		rebalance_domains(balance_cpu, CPU_IDLE);
+
+		rq = cpu_rq(balance_cpu);
+		if (time_after(this_rq->next_balance, rq->next_balance))
+			this_rq->next_balance = rq->next_balance;
+	}
+	nohz.next_balance = this_rq->next_balance;
+end:
+	clear_bit(NOHZ_BALANCE_KICK, nohz_flags(this_cpu));
+}
+
+/*
+ * Current heuristic for kicking the idle load balancer in the presence
+ * of an idle cpu is the system.
+ *   - This rq has more than one task.
+ *   - At any scheduler domain level, this cpu's scheduler group has multiple
+ *     busy cpu's exceeding the group's power.
+ *   - For SD_ASYM_PACKING, if the lower numbered cpu's in the scheduler
+ *     domain span are idle.
+ */
+static inline int nohz_kick_needed(struct rq *rq, int cpu)
+{
+	unsigned long now = jiffies;
+	struct sched_domain *sd;
+
+	if (unlikely(idle_cpu(cpu)))
+		return 0;
+
+       /*
+	* We may be recently in ticked or tickless idle mode. At the first
+	* busy tick after returning from idle, we will update the busy stats.
+	*/
+	set_cpu_sd_state_busy();
+	if (unlikely(test_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu)))) {
+		clear_bit(NOHZ_TICK_STOPPED, nohz_flags(cpu));
+		cpumask_clear_cpu(cpu, nohz.idle_cpus_mask);
+		atomic_dec(&nohz.nr_cpus);
+	}
+
+	/*
+	 * None are in tickless mode and hence no need for NOHZ idle load
+	 * balancing.
+	 */
+	if (likely(!atomic_read(&nohz.nr_cpus)))
+		return 0;
+
+	if (time_before(now, nohz.next_balance))
+		return 0;
+
+	if (rq->nr_running >= 2)
+		goto need_kick;
+
+	rcu_read_lock();
+	for_each_domain(cpu, sd) {
+		struct sched_group *sg = sd->groups;
+		struct sched_group_power *sgp = sg->sgp;
+		int nr_busy = atomic_read(&sgp->nr_busy_cpus);
+
+		if (sd->flags & SD_SHARE_PKG_RESOURCES && nr_busy > 1)
+			goto need_kick_unlock;
+
+		if (sd->flags & SD_ASYM_PACKING && nr_busy != sg->group_weight
+		    && (cpumask_first_and(nohz.idle_cpus_mask,
+					  sched_domain_span(sd)) < cpu))
+			goto need_kick_unlock;
+
+		if (!(sd->flags & (SD_SHARE_PKG_RESOURCES | SD_ASYM_PACKING)))
+			break;
+	}
+	rcu_read_unlock();
+	return 0;
+
+need_kick_unlock:
+	rcu_read_unlock();
+need_kick:
+	return 1;
+}
+#else
+static void nohz_idle_balance(int this_cpu, enum cpu_idle_type idle) { }
+#endif
+
+/*
+ * run_rebalance_domains is triggered when needed from the scheduler tick.
+ * Also triggered for nohz idle balancing (with nohz_balancing_kick set).
+ */
+static void run_rebalance_domains(struct softirq_action *h)
+{
+	int this_cpu = smp_processor_id();
+	struct rq *this_rq = cpu_rq(this_cpu);
+	enum cpu_idle_type idle = this_rq->idle_balance ?
+						CPU_IDLE : CPU_NOT_IDLE;
+
+	rebalance_domains(this_cpu, idle);
+
+	/*
+	 * If this cpu has a pending nohz_balance_kick, then do the
+	 * balancing on behalf of the other idle cpus whose ticks are
+	 * stopped.
+	 */
+	nohz_idle_balance(this_cpu, idle);
+}
+
+static inline int on_null_domain(int cpu)
+{
+	return !rcu_dereference_sched(cpu_rq(cpu)->sd);
+}
+
+/*
+ * Trigger the SCHED_SOFTIRQ if it is time to do periodic load balancing.
+ */
+void trigger_load_balance(struct rq *rq, int cpu)
+{
+	/* Don't need to rebalance while attached to NULL domain */
+	if (time_after_eq(jiffies, rq->next_balance) &&
+	    likely(!on_null_domain(cpu)))
+		raise_softirq(SCHED_SOFTIRQ);
+#ifdef CONFIG_NO_HZ
+	if (nohz_kick_needed(rq, cpu) && likely(!on_null_domain(cpu)))
+		nohz_balancer_kick(cpu);
+#endif
+}
+
+static void rq_online_fair(struct rq *rq)
+{
+	update_sysctl();
+}
+
+static void rq_offline_fair(struct rq *rq)
+{
+	update_sysctl();
+}
+
+#endif /* CONFIG_SMP */
+
+/*
+ * scheduler tick hitting a task of our scheduling class:
+ */
+static void task_tick_fair(struct rq *rq, struct task_struct *curr, int queued)
+{
+	struct cfs_rq *cfs_rq;
+	struct sched_entity *se = &curr->se;
+
+	for_each_sched_entity(se) {
+		cfs_rq = cfs_rq_of(se);
+		entity_tick(cfs_rq, se, queued);
+	}
+}
+
+/*
+ * called on fork with the child task as argument from the parent's context
+ *  - child not yet on the tasklist
+ *  - preemption disabled
+ */
+static void task_fork_fair(struct task_struct *p)
+{
+	struct cfs_rq *cfs_rq;
+	struct sched_entity *se = &p->se, *curr;
+	int this_cpu = smp_processor_id();
+	struct rq *rq = this_rq();
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&rq->lock, flags);
+
+	update_rq_clock(rq);
+
+	cfs_rq = task_cfs_rq(current);
+	curr = cfs_rq->curr;
+
+	if (unlikely(task_cpu(p) != this_cpu)) {
+		rcu_read_lock();
+		__set_task_cpu(p, this_cpu);
+		rcu_read_unlock();
+	}
+
+	update_curr(cfs_rq);
+
+	if (curr)
+		se->vruntime = curr->vruntime;
+	place_entity(cfs_rq, se, 1);
+
+	if (sysctl_sched_child_runs_first && curr && entity_before(curr, se)) {
+		/*
+		 * Upon rescheduling, sched_class::put_prev_task() will place
+		 * 'current' within the tree based on its new key value.
+		 */
+		swap(curr->vruntime, se->vruntime);
+		resched_task(rq->curr);
+	}
+
+	se->vruntime -= cfs_rq->min_vruntime;
+
+	raw_spin_unlock_irqrestore(&rq->lock, flags);
+}
+
+/*
+ * Priority of the task has changed. Check to see if we preempt
+ * the current task.
+ */
+static void
+prio_changed_fair(struct rq *rq, struct task_struct *p, int oldprio)
+{
+	if (!p->se.on_rq)
+		return;
+
+	/*
+	 * Reschedule if we are currently running on this runqueue and
+	 * our priority decreased, or if we are not currently running on
+	 * this runqueue and our priority is higher than the current's
+	 */
+	if (rq->curr == p) {
+		if (p->prio > oldprio)
+			resched_task(rq->curr);
+	} else
+		check_preempt_curr(rq, p, 0);
+}
+
+static void switched_from_fair(struct rq *rq, struct task_struct *p)
+{
+	struct sched_entity *se = &p->se;
+	struct cfs_rq *cfs_rq = cfs_rq_of(se);
+
+	/*
+	 * Ensure the task's vruntime is normalized, so that when its
+	 * switched back to the fair class the enqueue_entity(.flags=0) will
+	 * do the right thing.
+	 *
+	 * If it was on_rq, then the dequeue_entity(.flags=0) will already
+	 * have normalized the vruntime, if it was !on_rq, then only when
+	 * the task is sleeping will it still have non-normalized vruntime.
+	 */
+	if (!se->on_rq && p->state != TASK_RUNNING) {
+		/*
+		 * Fix up our vruntime so that the current sleep doesn't
+		 * cause 'unlimited' sleep bonus.
+		 */
+		place_entity(cfs_rq, se, 0);
+		se->vruntime -= cfs_rq->min_vruntime;
+	}
+}
+
+/*
+ * We switched to the sched_fair class.
+ */
+static void switched_to_fair(struct rq *rq, struct task_struct *p)
+{
+	if (!p->se.on_rq)
+		return;
+
+	/*
+	 * We were most likely switched from sched_rt, so
+	 * kick off the schedule if running, otherwise just see
+	 * if we can still preempt the current task.
+	 */
+	if (rq->curr == p)
+		resched_task(rq->curr);
+	else
+		check_preempt_curr(rq, p, 0);
+}
+
+/* Account for a task changing its policy or group.
+ *
+ * This routine is mostly called to set cfs_rq->curr field when a task
+ * migrates between groups/classes.
+ */
+static void set_curr_task_fair(struct rq *rq)
+{
+	struct sched_entity *se = &rq->curr->se;
+
+	for_each_sched_entity(se) {
+		struct cfs_rq *cfs_rq = cfs_rq_of(se);
+
+		set_next_entity(cfs_rq, se);
+		/* ensure bandwidth has been allocated on our new cfs_rq */
+		account_cfs_rq_runtime(cfs_rq, 0);
+	}
+}
+
+void init_cfs_rq(struct cfs_rq *cfs_rq)
+{
+	cfs_rq->tasks_timeline = RB_ROOT;
+	INIT_LIST_HEAD(&cfs_rq->tasks);
+	cfs_rq->min_vruntime = (u64)(-(1LL << 20));
+#ifndef CONFIG_64BIT
+	cfs_rq->min_vruntime_copy = cfs_rq->min_vruntime;
+#endif
+}
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+static void task_move_group_fair(struct task_struct *p, int on_rq)
+{
+	/*
+	 * If the task was not on the rq at the time of this cgroup movement
+	 * it must have been asleep, sleeping tasks keep their ->vruntime
+	 * absolute on their old rq until wakeup (needed for the fair sleeper
+	 * bonus in place_entity()).
+	 *
+	 * If it was on the rq, we've just 'preempted' it, which does convert
+	 * ->vruntime to a relative base.
+	 *
+	 * Make sure both cases convert their relative position when migrating
+	 * to another cgroup's rq. This does somewhat interfere with the
+	 * fair sleeper stuff for the first placement, but who cares.
+	 */
+	/*
+	 * When !on_rq, vruntime of the task has usually NOT been normalized.
+	 * But there are some cases where it has already been normalized:
+	 *
+	 * - Moving a forked child which is waiting for being woken up by
+	 *   wake_up_new_task().
+	 * - Moving a task which has been woken up by try_to_wake_up() and
+	 *   waiting for actually being woken up by sched_ttwu_pending().
+	 *
+	 * To prevent boost or penalty in the new cfs_rq caused by delta
+	 * min_vruntime between the two cfs_rqs, we skip vruntime adjustment.
+	 */
+	if (!on_rq && (!p->se.sum_exec_runtime || p->state == TASK_WAKING))
+		on_rq = 1;
+
+	if (!on_rq)
+		p->se.vruntime -= cfs_rq_of(&p->se)->min_vruntime;
+	set_task_rq(p, task_cpu(p));
+	if (!on_rq)
+		p->se.vruntime += cfs_rq_of(&p->se)->min_vruntime;
+}
+
+void free_fair_sched_group(struct task_group *tg)
+{
+	int i;
+
+	destroy_cfs_bandwidth(tg_cfs_bandwidth(tg));
+
+	for_each_possible_cpu(i) {
+		if (tg->cfs_rq)
+			kfree(tg->cfs_rq[i]);
+		if (tg->se)
+			kfree(tg->se[i]);
+	}
+
+	kfree(tg->cfs_rq);
+	kfree(tg->se);
+}
+
+int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
+{
+	struct cfs_rq *cfs_rq;
+	struct sched_entity *se;
+	int i;
+
+	tg->cfs_rq = kzalloc(sizeof(cfs_rq) * nr_cpu_ids, GFP_KERNEL);
+	if (!tg->cfs_rq)
+		goto err;
+	tg->se = kzalloc(sizeof(se) * nr_cpu_ids, GFP_KERNEL);
+	if (!tg->se)
+		goto err;
+
+	tg->shares = NICE_0_LOAD;
+
+	init_cfs_bandwidth(tg_cfs_bandwidth(tg));
+
+	for_each_possible_cpu(i) {
+		cfs_rq = kzalloc_node(sizeof(struct cfs_rq),
+				      GFP_KERNEL, cpu_to_node(i));
+		if (!cfs_rq)
+			goto err;
+
+		se = kzalloc_node(sizeof(struct sched_entity),
+				  GFP_KERNEL, cpu_to_node(i));
+		if (!se)
+			goto err_free_rq;
+
+		init_cfs_rq(cfs_rq);
+		init_tg_cfs_entry(tg, cfs_rq, se, i, parent->se[i]);
+	}
+
+	return 1;
+
+err_free_rq:
+	kfree(cfs_rq);
+err:
+	return 0;
+}
+
+void unregister_fair_sched_group(struct task_group *tg, int cpu)
+{
+	struct rq *rq = cpu_rq(cpu);
+	unsigned long flags;
+
+	/*
+	* Only empty task groups can be destroyed; so we can speculatively
+	* check on_list without danger of it being re-added.
+	*/
+	if (!tg->cfs_rq[cpu]->on_list)
+		return;
+
+	raw_spin_lock_irqsave(&rq->lock, flags);
+	list_del_leaf_cfs_rq(tg->cfs_rq[cpu]);
+	raw_spin_unlock_irqrestore(&rq->lock, flags);
+}
+
+void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
+			struct sched_entity *se, int cpu,
+			struct sched_entity *parent)
+{
+	struct rq *rq = cpu_rq(cpu);
+
+	cfs_rq->tg = tg;
+	cfs_rq->rq = rq;
+#ifdef CONFIG_SMP
+	/* allow initial update_cfs_load() to truncate */
+	cfs_rq->load_stamp = 1;
+#endif
+	init_cfs_rq_runtime(cfs_rq);
+
+	tg->cfs_rq[cpu] = cfs_rq;
+	tg->se[cpu] = se;
+
+	/* se could be NULL for root_task_group */
+	if (!se)
+		return;
+
+	if (!parent)
+		se->cfs_rq = &rq->cfs;
+	else
+		se->cfs_rq = parent->my_q;
+
+	se->my_q = cfs_rq;
+	update_load_set(&se->load, 0);
+	se->parent = parent;
+}
+
+static DEFINE_MUTEX(shares_mutex);
+
+int sched_group_set_shares(struct task_group *tg, unsigned long shares)
+{
+	int i;
+	unsigned long flags;
+
+	/*
+	 * We can't change the weight of the root cgroup.
+	 */
+	if (!tg->se[0])
+		return -EINVAL;
+
+	shares = clamp(shares, scale_load(MIN_SHARES), scale_load(MAX_SHARES));
+
+	mutex_lock(&shares_mutex);
+	if (tg->shares == shares)
+		goto done;
+
+	tg->shares = shares;
+	for_each_possible_cpu(i) {
+		struct rq *rq = cpu_rq(i);
+		struct sched_entity *se;
+
+		se = tg->se[i];
+		/* Propagate contribution to hierarchy */
+		raw_spin_lock_irqsave(&rq->lock, flags);
+		for_each_sched_entity(se)
+			update_cfs_shares(group_cfs_rq(se));
+		raw_spin_unlock_irqrestore(&rq->lock, flags);
+	}
+
+done:
+	mutex_unlock(&shares_mutex);
+	return 0;
+}
+#else /* CONFIG_FAIR_GROUP_SCHED */
+
+void free_fair_sched_group(struct task_group *tg) { }
+
+int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
+{
+	return 1;
+}
+
+void unregister_fair_sched_group(struct task_group *tg, int cpu) { }
+
+#endif /* CONFIG_FAIR_GROUP_SCHED */
+
+
+static unsigned int get_rr_interval_fair(struct rq *rq, struct task_struct *task)
+{
+	struct sched_entity *se = &task->se;
+	unsigned int rr_interval = 0;
+
+	/*
+	 * Time slice is 0 for SCHED_OTHER tasks that are on an otherwise
+	 * idle runqueue:
+	 */
+	if (rq->cfs.load.weight)
+		rr_interval = NS_TO_JIFFIES(sched_slice(&rq->cfs, se));
+
+	return rr_interval;
+}
+
+/*
+ * All the scheduling class methods:
+ */
+const struct sched_class fair_sched_class = {
+	.next			= &idle_sched_class,
+	.enqueue_task		= enqueue_task_fair,
+	.dequeue_task		= dequeue_task_fair,
+	.yield_task		= yield_task_fair,
+	.yield_to_task		= yield_to_task_fair,
+
+	.check_preempt_curr	= check_preempt_wakeup,
+
+	.pick_next_task		= pick_next_task_fair,
+	.put_prev_task		= put_prev_task_fair,
+
+#ifdef CONFIG_SMP
+	.select_task_rq		= select_task_rq_fair,
+
+	.rq_online		= rq_online_fair,
+	.rq_offline		= rq_offline_fair,
+
+	.task_waking		= task_waking_fair,
+#endif
+
+	.set_curr_task          = set_curr_task_fair,
+	.task_tick		= task_tick_fair,
+	.task_fork		= task_fork_fair,
+
+	.prio_changed		= prio_changed_fair,
+	.switched_from		= switched_from_fair,
+	.switched_to		= switched_to_fair,
+
+	.get_rr_interval	= get_rr_interval_fair,
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+	.task_move_group	= task_move_group_fair,
+#endif
+};
+
+#ifdef CONFIG_SCHED_DEBUG
+void print_cfs_stats(struct seq_file *m, int cpu)
+{
+	struct cfs_rq *cfs_rq;
+
+	rcu_read_lock();
+	for_each_leaf_cfs_rq(cpu_rq(cpu), cfs_rq)
+		print_cfs_rq(m, cpu, cfs_rq);
+	rcu_read_unlock();
+}
+#endif
+
+__init void init_sched_fair_class(void)
+{
+#ifdef CONFIG_SMP
+	open_softirq(SCHED_SOFTIRQ, run_rebalance_domains);
+
+#ifdef CONFIG_NO_HZ
+	zalloc_cpumask_var(&nohz.idle_cpus_mask, GFP_NOWAIT);
+#endif
+#endif /* SMP */
+
+}
diff --git a/kernel/sched/features.h b/kernel/sched/features.h
new file mode 100644
index 00000000000..e61fd73913d
--- /dev/null
+++ b/kernel/sched/features.h
@@ -0,0 +1,70 @@
+/*
+ * Only give sleepers 50% of their service deficit. This allows
+ * them to run sooner, but does not allow tons of sleepers to
+ * rip the spread apart.
+ */
+SCHED_FEAT(GENTLE_FAIR_SLEEPERS, true)
+
+/*
+ * Place new tasks ahead so that they do not starve already running
+ * tasks
+ */
+SCHED_FEAT(START_DEBIT, true)
+
+/*
+ * Based on load and program behaviour, see if it makes sense to place
+ * a newly woken task on the same cpu as the task that woke it --
+ * improve cache locality. Typically used with SYNC wakeups as
+ * generated by pipes and the like, see also SYNC_WAKEUPS.
+ */
+SCHED_FEAT(AFFINE_WAKEUPS, true)
+
+/*
+ * Prefer to schedule the task we woke last (assuming it failed
+ * wakeup-preemption), since its likely going to consume data we
+ * touched, increases cache locality.
+ */
+SCHED_FEAT(NEXT_BUDDY, false)
+
+/*
+ * Prefer to schedule the task that ran last (when we did
+ * wake-preempt) as that likely will touch the same data, increases
+ * cache locality.
+ */
+SCHED_FEAT(LAST_BUDDY, true)
+
+/*
+ * Consider buddies to be cache hot, decreases the likelyness of a
+ * cache buddy being migrated away, increases cache locality.
+ */
+SCHED_FEAT(CACHE_HOT_BUDDY, true)
+
+/*
+ * Use arch dependent cpu power functions
+ */
+SCHED_FEAT(ARCH_POWER, false)
+
+SCHED_FEAT(HRTICK, false)
+SCHED_FEAT(DOUBLE_TICK, false)
+SCHED_FEAT(LB_BIAS, true)
+
+/*
+ * Spin-wait on mutex acquisition when the mutex owner is running on
+ * another cpu -- assumes that when the owner is running, it will soon
+ * release the lock. Decreases scheduling overhead.
+ */
+SCHED_FEAT(OWNER_SPIN, true)
+
+/*
+ * Decrement CPU power based on time not spent running tasks
+ */
+SCHED_FEAT(NONTASK_POWER, true)
+
+/*
+ * Queue remote wakeups on the target CPU and process them
+ * using the scheduler IPI. Reduces rq->lock contention/bounces.
+ */
+SCHED_FEAT(TTWU_QUEUE, true)
+
+SCHED_FEAT(FORCE_SD_OVERLAP, false)
+SCHED_FEAT(RT_RUNTIME_SHARE, true)
diff --git a/kernel/sched/idle_task.c b/kernel/sched/idle_task.c
new file mode 100644
index 00000000000..91b4c957f28
--- /dev/null
+++ b/kernel/sched/idle_task.c
@@ -0,0 +1,99 @@
+#include "sched.h"
+
+/*
+ * idle-task scheduling class.
+ *
+ * (NOTE: these are not related to SCHED_IDLE tasks which are
+ *  handled in sched_fair.c)
+ */
+
+#ifdef CONFIG_SMP
+static int
+select_task_rq_idle(struct task_struct *p, int sd_flag, int flags)
+{
+	return task_cpu(p); /* IDLE tasks as never migrated */
+}
+#endif /* CONFIG_SMP */
+/*
+ * Idle tasks are unconditionally rescheduled:
+ */
+static void check_preempt_curr_idle(struct rq *rq, struct task_struct *p, int flags)
+{
+	resched_task(rq->idle);
+}
+
+static struct task_struct *pick_next_task_idle(struct rq *rq)
+{
+	schedstat_inc(rq, sched_goidle);
+	calc_load_account_idle(rq);
+	return rq->idle;
+}
+
+/*
+ * It is not legal to sleep in the idle task - print a warning
+ * message if some code attempts to do it:
+ */
+static void
+dequeue_task_idle(struct rq *rq, struct task_struct *p, int flags)
+{
+	raw_spin_unlock_irq(&rq->lock);
+	printk(KERN_ERR "bad: scheduling from the idle thread!\n");
+	dump_stack();
+	raw_spin_lock_irq(&rq->lock);
+}
+
+static void put_prev_task_idle(struct rq *rq, struct task_struct *prev)
+{
+}
+
+static void task_tick_idle(struct rq *rq, struct task_struct *curr, int queued)
+{
+}
+
+static void set_curr_task_idle(struct rq *rq)
+{
+}
+
+static void switched_to_idle(struct rq *rq, struct task_struct *p)
+{
+	BUG();
+}
+
+static void
+prio_changed_idle(struct rq *rq, struct task_struct *p, int oldprio)
+{
+	BUG();
+}
+
+static unsigned int get_rr_interval_idle(struct rq *rq, struct task_struct *task)
+{
+	return 0;
+}
+
+/*
+ * Simple, special scheduling class for the per-CPU idle tasks:
+ */
+const struct sched_class idle_sched_class = {
+	/* .next is NULL */
+	/* no enqueue/yield_task for idle tasks */
+
+	/* dequeue is not valid, we print a debug message there: */
+	.dequeue_task		= dequeue_task_idle,
+
+	.check_preempt_curr	= check_preempt_curr_idle,
+
+	.pick_next_task		= pick_next_task_idle,
+	.put_prev_task		= put_prev_task_idle,
+
+#ifdef CONFIG_SMP
+	.select_task_rq		= select_task_rq_idle,
+#endif
+
+	.set_curr_task          = set_curr_task_idle,
+	.task_tick		= task_tick_idle,
+
+	.get_rr_interval	= get_rr_interval_idle,
+
+	.prio_changed		= prio_changed_idle,
+	.switched_to		= switched_to_idle,
+};
diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
new file mode 100644
index 00000000000..3640ebbb466
--- /dev/null
+++ b/kernel/sched/rt.c
@@ -0,0 +1,2048 @@
+/*
+ * Real-Time Scheduling Class (mapped to the SCHED_FIFO and SCHED_RR
+ * policies)
+ */
+
+#include "sched.h"
+
+#include <linux/slab.h>
+
+static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun);
+
+struct rt_bandwidth def_rt_bandwidth;
+
+static enum hrtimer_restart sched_rt_period_timer(struct hrtimer *timer)
+{
+	struct rt_bandwidth *rt_b =
+		container_of(timer, struct rt_bandwidth, rt_period_timer);
+	ktime_t now;
+	int overrun;
+	int idle = 0;
+
+	for (;;) {
+		now = hrtimer_cb_get_time(timer);
+		overrun = hrtimer_forward(timer, now, rt_b->rt_period);
+
+		if (!overrun)
+			break;
+
+		idle = do_sched_rt_period_timer(rt_b, overrun);
+	}
+
+	return idle ? HRTIMER_NORESTART : HRTIMER_RESTART;
+}
+
+void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime)
+{
+	rt_b->rt_period = ns_to_ktime(period);
+	rt_b->rt_runtime = runtime;
+
+	raw_spin_lock_init(&rt_b->rt_runtime_lock);
+
+	hrtimer_init(&rt_b->rt_period_timer,
+			CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	rt_b->rt_period_timer.function = sched_rt_period_timer;
+}
+
+static void start_rt_bandwidth(struct rt_bandwidth *rt_b)
+{
+	if (!rt_bandwidth_enabled() || rt_b->rt_runtime == RUNTIME_INF)
+		return;
+
+	if (hrtimer_active(&rt_b->rt_period_timer))
+		return;
+
+	raw_spin_lock(&rt_b->rt_runtime_lock);
+	start_bandwidth_timer(&rt_b->rt_period_timer, rt_b->rt_period);
+	raw_spin_unlock(&rt_b->rt_runtime_lock);
+}
+
+void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq)
+{
+	struct rt_prio_array *array;
+	int i;
+
+	array = &rt_rq->active;
+	for (i = 0; i < MAX_RT_PRIO; i++) {
+		INIT_LIST_HEAD(array->queue + i);
+		__clear_bit(i, array->bitmap);
+	}
+	/* delimiter for bitsearch: */
+	__set_bit(MAX_RT_PRIO, array->bitmap);
+
+#if defined CONFIG_SMP
+	rt_rq->highest_prio.curr = MAX_RT_PRIO;
+	rt_rq->highest_prio.next = MAX_RT_PRIO;
+	rt_rq->rt_nr_migratory = 0;
+	rt_rq->overloaded = 0;
+	plist_head_init(&rt_rq->pushable_tasks);
+#endif
+
+	rt_rq->rt_time = 0;
+	rt_rq->rt_throttled = 0;
+	rt_rq->rt_runtime = 0;
+	raw_spin_lock_init(&rt_rq->rt_runtime_lock);
+}
+
+#ifdef CONFIG_RT_GROUP_SCHED
+static void destroy_rt_bandwidth(struct rt_bandwidth *rt_b)
+{
+	hrtimer_cancel(&rt_b->rt_period_timer);
+}
+
+#define rt_entity_is_task(rt_se) (!(rt_se)->my_q)
+
+static inline struct task_struct *rt_task_of(struct sched_rt_entity *rt_se)
+{
+#ifdef CONFIG_SCHED_DEBUG
+	WARN_ON_ONCE(!rt_entity_is_task(rt_se));
+#endif
+	return container_of(rt_se, struct task_struct, rt);
+}
+
+static inline struct rq *rq_of_rt_rq(struct rt_rq *rt_rq)
+{
+	return rt_rq->rq;
+}
+
+static inline struct rt_rq *rt_rq_of_se(struct sched_rt_entity *rt_se)
+{
+	return rt_se->rt_rq;
+}
+
+void free_rt_sched_group(struct task_group *tg)
+{
+	int i;
+
+	if (tg->rt_se)
+		destroy_rt_bandwidth(&tg->rt_bandwidth);
+
+	for_each_possible_cpu(i) {
+		if (tg->rt_rq)
+			kfree(tg->rt_rq[i]);
+		if (tg->rt_se)
+			kfree(tg->rt_se[i]);
+	}
+
+	kfree(tg->rt_rq);
+	kfree(tg->rt_se);
+}
+
+void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
+		struct sched_rt_entity *rt_se, int cpu,
+		struct sched_rt_entity *parent)
+{
+	struct rq *rq = cpu_rq(cpu);
+
+	rt_rq->highest_prio.curr = MAX_RT_PRIO;
+	rt_rq->rt_nr_boosted = 0;
+	rt_rq->rq = rq;
+	rt_rq->tg = tg;
+
+	tg->rt_rq[cpu] = rt_rq;
+	tg->rt_se[cpu] = rt_se;
+
+	if (!rt_se)
+		return;
+
+	if (!parent)
+		rt_se->rt_rq = &rq->rt;
+	else
+		rt_se->rt_rq = parent->my_q;
+
+	rt_se->my_q = rt_rq;
+	rt_se->parent = parent;
+	INIT_LIST_HEAD(&rt_se->run_list);
+}
+
+int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent)
+{
+	struct rt_rq *rt_rq;
+	struct sched_rt_entity *rt_se;
+	int i;
+
+	tg->rt_rq = kzalloc(sizeof(rt_rq) * nr_cpu_ids, GFP_KERNEL);
+	if (!tg->rt_rq)
+		goto err;
+	tg->rt_se = kzalloc(sizeof(rt_se) * nr_cpu_ids, GFP_KERNEL);
+	if (!tg->rt_se)
+		goto err;
+
+	init_rt_bandwidth(&tg->rt_bandwidth,
+			ktime_to_ns(def_rt_bandwidth.rt_period), 0);
+
+	for_each_possible_cpu(i) {
+		rt_rq = kzalloc_node(sizeof(struct rt_rq),
+				     GFP_KERNEL, cpu_to_node(i));
+		if (!rt_rq)
+			goto err;
+
+		rt_se = kzalloc_node(sizeof(struct sched_rt_entity),
+				     GFP_KERNEL, cpu_to_node(i));
+		if (!rt_se)
+			goto err_free_rq;
+
+		init_rt_rq(rt_rq, cpu_rq(i));
+		rt_rq->rt_runtime = tg->rt_bandwidth.rt_runtime;
+		init_tg_rt_entry(tg, rt_rq, rt_se, i, parent->rt_se[i]);
+	}
+
+	return 1;
+
+err_free_rq:
+	kfree(rt_rq);
+err:
+	return 0;
+}
+
+#else /* CONFIG_RT_GROUP_SCHED */
+
+#define rt_entity_is_task(rt_se) (1)
+
+static inline struct task_struct *rt_task_of(struct sched_rt_entity *rt_se)
+{
+	return container_of(rt_se, struct task_struct, rt);
+}
+
+static inline struct rq *rq_of_rt_rq(struct rt_rq *rt_rq)
+{
+	return container_of(rt_rq, struct rq, rt);
+}
+
+static inline struct rt_rq *rt_rq_of_se(struct sched_rt_entity *rt_se)
+{
+	struct task_struct *p = rt_task_of(rt_se);
+	struct rq *rq = task_rq(p);
+
+	return &rq->rt;
+}
+
+void free_rt_sched_group(struct task_group *tg) { }
+
+int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent)
+{
+	return 1;
+}
+#endif /* CONFIG_RT_GROUP_SCHED */
+
+#ifdef CONFIG_SMP
+
+static inline int rt_overloaded(struct rq *rq)
+{
+	return atomic_read(&rq->rd->rto_count);
+}
+
+static inline void rt_set_overload(struct rq *rq)
+{
+	if (!rq->online)
+		return;
+
+	cpumask_set_cpu(rq->cpu, rq->rd->rto_mask);
+	/*
+	 * Make sure the mask is visible before we set
+	 * the overload count. That is checked to determine
+	 * if we should look at the mask. It would be a shame
+	 * if we looked at the mask, but the mask was not
+	 * updated yet.
+	 */
+	wmb();
+	atomic_inc(&rq->rd->rto_count);
+}
+
+static inline void rt_clear_overload(struct rq *rq)
+{
+	if (!rq->online)
+		return;
+
+	/* the order here really doesn't matter */
+	atomic_dec(&rq->rd->rto_count);
+	cpumask_clear_cpu(rq->cpu, rq->rd->rto_mask);
+}
+
+static void update_rt_migration(struct rt_rq *rt_rq)
+{
+	if (rt_rq->rt_nr_migratory && rt_rq->rt_nr_total > 1) {
+		if (!rt_rq->overloaded) {
+			rt_set_overload(rq_of_rt_rq(rt_rq));
+			rt_rq->overloaded = 1;
+		}
+	} else if (rt_rq->overloaded) {
+		rt_clear_overload(rq_of_rt_rq(rt_rq));
+		rt_rq->overloaded = 0;
+	}
+}
+
+static void inc_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
+{
+	if (!rt_entity_is_task(rt_se))
+		return;
+
+	rt_rq = &rq_of_rt_rq(rt_rq)->rt;
+
+	rt_rq->rt_nr_total++;
+	if (rt_se->nr_cpus_allowed > 1)
+		rt_rq->rt_nr_migratory++;
+
+	update_rt_migration(rt_rq);
+}
+
+static void dec_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
+{
+	if (!rt_entity_is_task(rt_se))
+		return;
+
+	rt_rq = &rq_of_rt_rq(rt_rq)->rt;
+
+	rt_rq->rt_nr_total--;
+	if (rt_se->nr_cpus_allowed > 1)
+		rt_rq->rt_nr_migratory--;
+
+	update_rt_migration(rt_rq);
+}
+
+static inline int has_pushable_tasks(struct rq *rq)
+{
+	return !plist_head_empty(&rq->rt.pushable_tasks);
+}
+
+static void enqueue_pushable_task(struct rq *rq, struct task_struct *p)
+{
+	plist_del(&p->pushable_tasks, &rq->rt.pushable_tasks);
+	plist_node_init(&p->pushable_tasks, p->prio);
+	plist_add(&p->pushable_tasks, &rq->rt.pushable_tasks);
+
+	/* Update the highest prio pushable task */
+	if (p->prio < rq->rt.highest_prio.next)
+		rq->rt.highest_prio.next = p->prio;
+}
+
+static void dequeue_pushable_task(struct rq *rq, struct task_struct *p)
+{
+	plist_del(&p->pushable_tasks, &rq->rt.pushable_tasks);
+
+	/* Update the new highest prio pushable task */
+	if (has_pushable_tasks(rq)) {
+		p = plist_first_entry(&rq->rt.pushable_tasks,
+				      struct task_struct, pushable_tasks);
+		rq->rt.highest_prio.next = p->prio;
+	} else
+		rq->rt.highest_prio.next = MAX_RT_PRIO;
+}
+
+#else
+
+static inline void enqueue_pushable_task(struct rq *rq, struct task_struct *p)
+{
+}
+
+static inline void dequeue_pushable_task(struct rq *rq, struct task_struct *p)
+{
+}
+
+static inline
+void inc_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
+{
+}
+
+static inline
+void dec_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
+{
+}
+
+#endif /* CONFIG_SMP */
+
+static inline int on_rt_rq(struct sched_rt_entity *rt_se)
+{
+	return !list_empty(&rt_se->run_list);
+}
+
+#ifdef CONFIG_RT_GROUP_SCHED
+
+static inline u64 sched_rt_runtime(struct rt_rq *rt_rq)
+{
+	if (!rt_rq->tg)
+		return RUNTIME_INF;
+
+	return rt_rq->rt_runtime;
+}
+
+static inline u64 sched_rt_period(struct rt_rq *rt_rq)
+{
+	return ktime_to_ns(rt_rq->tg->rt_bandwidth.rt_period);
+}
+
+typedef struct task_group *rt_rq_iter_t;
+
+static inline struct task_group *next_task_group(struct task_group *tg)
+{
+	do {
+		tg = list_entry_rcu(tg->list.next,
+			typeof(struct task_group), list);
+	} while (&tg->list != &task_groups && task_group_is_autogroup(tg));
+
+	if (&tg->list == &task_groups)
+		tg = NULL;
+
+	return tg;
+}
+
+#define for_each_rt_rq(rt_rq, iter, rq)					\
+	for (iter = container_of(&task_groups, typeof(*iter), list);	\
+		(iter = next_task_group(iter)) &&			\
+		(rt_rq = iter->rt_rq[cpu_of(rq)]);)
+
+static inline void list_add_leaf_rt_rq(struct rt_rq *rt_rq)
+{
+	list_add_rcu(&rt_rq->leaf_rt_rq_list,
+			&rq_of_rt_rq(rt_rq)->leaf_rt_rq_list);
+}
+
+static inline void list_del_leaf_rt_rq(struct rt_rq *rt_rq)
+{
+	list_del_rcu(&rt_rq->leaf_rt_rq_list);
+}
+
+#define for_each_leaf_rt_rq(rt_rq, rq) \
+	list_for_each_entry_rcu(rt_rq, &rq->leaf_rt_rq_list, leaf_rt_rq_list)
+
+#define for_each_sched_rt_entity(rt_se) \
+	for (; rt_se; rt_se = rt_se->parent)
+
+static inline struct rt_rq *group_rt_rq(struct sched_rt_entity *rt_se)
+{
+	return rt_se->my_q;
+}
+
+static void enqueue_rt_entity(struct sched_rt_entity *rt_se, bool head);
+static void dequeue_rt_entity(struct sched_rt_entity *rt_se);
+
+static void sched_rt_rq_enqueue(struct rt_rq *rt_rq)
+{
+	struct task_struct *curr = rq_of_rt_rq(rt_rq)->curr;
+	struct sched_rt_entity *rt_se;
+
+	int cpu = cpu_of(rq_of_rt_rq(rt_rq));
+
+	rt_se = rt_rq->tg->rt_se[cpu];
+
+	if (rt_rq->rt_nr_running) {
+		if (rt_se && !on_rt_rq(rt_se))
+			enqueue_rt_entity(rt_se, false);
+		if (rt_rq->highest_prio.curr < curr->prio)
+			resched_task(curr);
+	}
+}
+
+static void sched_rt_rq_dequeue(struct rt_rq *rt_rq)
+{
+	struct sched_rt_entity *rt_se;
+	int cpu = cpu_of(rq_of_rt_rq(rt_rq));
+
+	rt_se = rt_rq->tg->rt_se[cpu];
+
+	if (rt_se && on_rt_rq(rt_se))
+		dequeue_rt_entity(rt_se);
+}
+
+static inline int rt_rq_throttled(struct rt_rq *rt_rq)
+{
+	return rt_rq->rt_throttled && !rt_rq->rt_nr_boosted;
+}
+
+static int rt_se_boosted(struct sched_rt_entity *rt_se)
+{
+	struct rt_rq *rt_rq = group_rt_rq(rt_se);
+	struct task_struct *p;
+
+	if (rt_rq)
+		return !!rt_rq->rt_nr_boosted;
+
+	p = rt_task_of(rt_se);
+	return p->prio != p->normal_prio;
+}
+
+#ifdef CONFIG_SMP
+static inline const struct cpumask *sched_rt_period_mask(void)
+{
+	return cpu_rq(smp_processor_id())->rd->span;
+}
+#else
+static inline const struct cpumask *sched_rt_period_mask(void)
+{
+	return cpu_online_mask;
+}
+#endif
+
+static inline
+struct rt_rq *sched_rt_period_rt_rq(struct rt_bandwidth *rt_b, int cpu)
+{
+	return container_of(rt_b, struct task_group, rt_bandwidth)->rt_rq[cpu];
+}
+
+static inline struct rt_bandwidth *sched_rt_bandwidth(struct rt_rq *rt_rq)
+{
+	return &rt_rq->tg->rt_bandwidth;
+}
+
+#else /* !CONFIG_RT_GROUP_SCHED */
+
+static inline u64 sched_rt_runtime(struct rt_rq *rt_rq)
+{
+	return rt_rq->rt_runtime;
+}
+
+static inline u64 sched_rt_period(struct rt_rq *rt_rq)
+{
+	return ktime_to_ns(def_rt_bandwidth.rt_period);
+}
+
+typedef struct rt_rq *rt_rq_iter_t;
+
+#define for_each_rt_rq(rt_rq, iter, rq) \
+	for ((void) iter, rt_rq = &rq->rt; rt_rq; rt_rq = NULL)
+
+static inline void list_add_leaf_rt_rq(struct rt_rq *rt_rq)
+{
+}
+
+static inline void list_del_leaf_rt_rq(struct rt_rq *rt_rq)
+{
+}
+
+#define for_each_leaf_rt_rq(rt_rq, rq) \
+	for (rt_rq = &rq->rt; rt_rq; rt_rq = NULL)
+
+#define for_each_sched_rt_entity(rt_se) \
+	for (; rt_se; rt_se = NULL)
+
+static inline struct rt_rq *group_rt_rq(struct sched_rt_entity *rt_se)
+{
+	return NULL;
+}
+
+static inline void sched_rt_rq_enqueue(struct rt_rq *rt_rq)
+{
+	if (rt_rq->rt_nr_running)
+		resched_task(rq_of_rt_rq(rt_rq)->curr);
+}
+
+static inline void sched_rt_rq_dequeue(struct rt_rq *rt_rq)
+{
+}
+
+static inline int rt_rq_throttled(struct rt_rq *rt_rq)
+{
+	return rt_rq->rt_throttled;
+}
+
+static inline const struct cpumask *sched_rt_period_mask(void)
+{
+	return cpu_online_mask;
+}
+
+static inline
+struct rt_rq *sched_rt_period_rt_rq(struct rt_bandwidth *rt_b, int cpu)
+{
+	return &cpu_rq(cpu)->rt;
+}
+
+static inline struct rt_bandwidth *sched_rt_bandwidth(struct rt_rq *rt_rq)
+{
+	return &def_rt_bandwidth;
+}
+
+#endif /* CONFIG_RT_GROUP_SCHED */
+
+#ifdef CONFIG_SMP
+/*
+ * We ran out of runtime, see if we can borrow some from our neighbours.
+ */
+static int do_balance_runtime(struct rt_rq *rt_rq)
+{
+	struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);
+	struct root_domain *rd = cpu_rq(smp_processor_id())->rd;
+	int i, weight, more = 0;
+	u64 rt_period;
+
+	weight = cpumask_weight(rd->span);
+
+	raw_spin_lock(&rt_b->rt_runtime_lock);
+	rt_period = ktime_to_ns(rt_b->rt_period);
+	for_each_cpu(i, rd->span) {
+		struct rt_rq *iter = sched_rt_period_rt_rq(rt_b, i);
+		s64 diff;
+
+		if (iter == rt_rq)
+			continue;
+
+		raw_spin_lock(&iter->rt_runtime_lock);
+		/*
+		 * Either all rqs have inf runtime and there's nothing to steal
+		 * or __disable_runtime() below sets a specific rq to inf to
+		 * indicate its been disabled and disalow stealing.
+		 */
+		if (iter->rt_runtime == RUNTIME_INF)
+			goto next;
+
+		/*
+		 * From runqueues with spare time, take 1/n part of their
+		 * spare time, but no more than our period.
+		 */
+		diff = iter->rt_runtime - iter->rt_time;
+		if (diff > 0) {
+			diff = div_u64((u64)diff, weight);
+			if (rt_rq->rt_runtime + diff > rt_period)
+				diff = rt_period - rt_rq->rt_runtime;
+			iter->rt_runtime -= diff;
+			rt_rq->rt_runtime += diff;
+			more = 1;
+			if (rt_rq->rt_runtime == rt_period) {
+				raw_spin_unlock(&iter->rt_runtime_lock);
+				break;
+			}
+		}
+next:
+		raw_spin_unlock(&iter->rt_runtime_lock);
+	}
+	raw_spin_unlock(&rt_b->rt_runtime_lock);
+
+	return more;
+}
+
+/*
+ * Ensure this RQ takes back all the runtime it lend to its neighbours.
+ */
+static void __disable_runtime(struct rq *rq)
+{
+	struct root_domain *rd = rq->rd;
+	rt_rq_iter_t iter;
+	struct rt_rq *rt_rq;
+
+	if (unlikely(!scheduler_running))
+		return;
+
+	for_each_rt_rq(rt_rq, iter, rq) {
+		struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);
+		s64 want;
+		int i;
+
+		raw_spin_lock(&rt_b->rt_runtime_lock);
+		raw_spin_lock(&rt_rq->rt_runtime_lock);
+		/*
+		 * Either we're all inf and nobody needs to borrow, or we're
+		 * already disabled and thus have nothing to do, or we have
+		 * exactly the right amount of runtime to take out.
+		 */
+		if (rt_rq->rt_runtime == RUNTIME_INF ||
+				rt_rq->rt_runtime == rt_b->rt_runtime)
+			goto balanced;
+		raw_spin_unlock(&rt_rq->rt_runtime_lock);
+
+		/*
+		 * Calculate the difference between what we started out with
+		 * and what we current have, that's the amount of runtime
+		 * we lend and now have to reclaim.
+		 */
+		want = rt_b->rt_runtime - rt_rq->rt_runtime;
+
+		/*
+		 * Greedy reclaim, take back as much as we can.
+		 */
+		for_each_cpu(i, rd->span) {
+			struct rt_rq *iter = sched_rt_period_rt_rq(rt_b, i);
+			s64 diff;
+
+			/*
+			 * Can't reclaim from ourselves or disabled runqueues.
+			 */
+			if (iter == rt_rq || iter->rt_runtime == RUNTIME_INF)
+				continue;
+
+			raw_spin_lock(&iter->rt_runtime_lock);
+			if (want > 0) {
+				diff = min_t(s64, iter->rt_runtime, want);
+				iter->rt_runtime -= diff;
+				want -= diff;
+			} else {
+				iter->rt_runtime -= want;
+				want -= want;
+			}
+			raw_spin_unlock(&iter->rt_runtime_lock);
+
+			if (!want)
+				break;
+		}
+
+		raw_spin_lock(&rt_rq->rt_runtime_lock);
+		/*
+		 * We cannot be left wanting - that would mean some runtime
+		 * leaked out of the system.
+		 */
+		BUG_ON(want);
+balanced:
+		/*
+		 * Disable all the borrow logic by pretending we have inf
+		 * runtime - in which case borrowing doesn't make sense.
+		 */
+		rt_rq->rt_runtime = RUNTIME_INF;
+		raw_spin_unlock(&rt_rq->rt_runtime_lock);
+		raw_spin_unlock(&rt_b->rt_runtime_lock);
+	}
+}
+
+static void disable_runtime(struct rq *rq)
+{
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&rq->lock, flags);
+	__disable_runtime(rq);
+	raw_spin_unlock_irqrestore(&rq->lock, flags);
+}
+
+static void __enable_runtime(struct rq *rq)
+{
+	rt_rq_iter_t iter;
+	struct rt_rq *rt_rq;
+
+	if (unlikely(!scheduler_running))
+		return;
+
+	/*
+	 * Reset each runqueue's bandwidth settings
+	 */
+	for_each_rt_rq(rt_rq, iter, rq) {
+		struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);
+
+		raw_spin_lock(&rt_b->rt_runtime_lock);
+		raw_spin_lock(&rt_rq->rt_runtime_lock);
+		rt_rq->rt_runtime = rt_b->rt_runtime;
+		rt_rq->rt_time = 0;
+		rt_rq->rt_throttled = 0;
+		raw_spin_unlock(&rt_rq->rt_runtime_lock);
+		raw_spin_unlock(&rt_b->rt_runtime_lock);
+	}
+}
+
+static void enable_runtime(struct rq *rq)
+{
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&rq->lock, flags);
+	__enable_runtime(rq);
+	raw_spin_unlock_irqrestore(&rq->lock, flags);
+}
+
+int update_runtime(struct notifier_block *nfb, unsigned long action, void *hcpu)
+{
+	int cpu = (int)(long)hcpu;
+
+	switch (action) {
+	case CPU_DOWN_PREPARE:
+	case CPU_DOWN_PREPARE_FROZEN:
+		disable_runtime(cpu_rq(cpu));
+		return NOTIFY_OK;
+
+	case CPU_DOWN_FAILED:
+	case CPU_DOWN_FAILED_FROZEN:
+	case CPU_ONLINE:
+	case CPU_ONLINE_FROZEN:
+		enable_runtime(cpu_rq(cpu));
+		return NOTIFY_OK;
+
+	default:
+		return NOTIFY_DONE;
+	}
+}
+
+static int balance_runtime(struct rt_rq *rt_rq)
+{
+	int more = 0;
+
+	if (!sched_feat(RT_RUNTIME_SHARE))
+		return more;
+
+	if (rt_rq->rt_time > rt_rq->rt_runtime) {
+		raw_spin_unlock(&rt_rq->rt_runtime_lock);
+		more = do_balance_runtime(rt_rq);
+		raw_spin_lock(&rt_rq->rt_runtime_lock);
+	}
+
+	return more;
+}
+#else /* !CONFIG_SMP */
+static inline int balance_runtime(struct rt_rq *rt_rq)
+{
+	return 0;
+}
+#endif /* CONFIG_SMP */
+
+static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun)
+{
+	int i, idle = 1;
+	const struct cpumask *span;
+
+	if (!rt_bandwidth_enabled() || rt_b->rt_runtime == RUNTIME_INF)
+		return 1;
+
+	span = sched_rt_period_mask();
+	for_each_cpu(i, span) {
+		int enqueue = 0;
+		struct rt_rq *rt_rq = sched_rt_period_rt_rq(rt_b, i);
+		struct rq *rq = rq_of_rt_rq(rt_rq);
+
+		raw_spin_lock(&rq->lock);
+		if (rt_rq->rt_time) {
+			u64 runtime;
+
+			raw_spin_lock(&rt_rq->rt_runtime_lock);
+			if (rt_rq->rt_throttled)
+				balance_runtime(rt_rq);
+			runtime = rt_rq->rt_runtime;
+			rt_rq->rt_time -= min(rt_rq->rt_time, overrun*runtime);
+			if (rt_rq->rt_throttled && rt_rq->rt_time < runtime) {
+				rt_rq->rt_throttled = 0;
+				enqueue = 1;
+
+				/*
+				 * Force a clock update if the CPU was idle,
+				 * lest wakeup -> unthrottle time accumulate.
+				 */
+				if (rt_rq->rt_nr_running && rq->curr == rq->idle)
+					rq->skip_clock_update = -1;
+			}
+			if (rt_rq->rt_time || rt_rq->rt_nr_running)
+				idle = 0;
+			raw_spin_unlock(&rt_rq->rt_runtime_lock);
+		} else if (rt_rq->rt_nr_running) {
+			idle = 0;
+			if (!rt_rq_throttled(rt_rq))
+				enqueue = 1;
+		}
+
+		if (enqueue)
+			sched_rt_rq_enqueue(rt_rq);
+		raw_spin_unlock(&rq->lock);
+	}
+
+	return idle;
+}
+
+static inline int rt_se_prio(struct sched_rt_entity *rt_se)
+{
+#ifdef CONFIG_RT_GROUP_SCHED
+	struct rt_rq *rt_rq = group_rt_rq(rt_se);
+
+	if (rt_rq)
+		return rt_rq->highest_prio.curr;
+#endif
+
+	return rt_task_of(rt_se)->prio;
+}
+
+static int sched_rt_runtime_exceeded(struct rt_rq *rt_rq)
+{
+	u64 runtime = sched_rt_runtime(rt_rq);
+
+	if (rt_rq->rt_throttled)
+		return rt_rq_throttled(rt_rq);
+
+	if (runtime >= sched_rt_period(rt_rq))
+		return 0;
+
+	balance_runtime(rt_rq);
+	runtime = sched_rt_runtime(rt_rq);
+	if (runtime == RUNTIME_INF)
+		return 0;
+
+	if (rt_rq->rt_time > runtime) {
+		rt_rq->rt_throttled = 1;
+		printk_once(KERN_WARNING "sched: RT throttling activated\n");
+		if (rt_rq_throttled(rt_rq)) {
+			sched_rt_rq_dequeue(rt_rq);
+			return 1;
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * Update the current task's runtime statistics. Skip current tasks that
+ * are not in our scheduling class.
+ */
+static void update_curr_rt(struct rq *rq)
+{
+	struct task_struct *curr = rq->curr;
+	struct sched_rt_entity *rt_se = &curr->rt;
+	struct rt_rq *rt_rq = rt_rq_of_se(rt_se);
+	u64 delta_exec;
+
+	if (curr->sched_class != &rt_sched_class)
+		return;
+
+	delta_exec = rq->clock_task - curr->se.exec_start;
+	if (unlikely((s64)delta_exec < 0))
+		delta_exec = 0;
+
+	schedstat_set(curr->se.statistics.exec_max, max(curr->se.statistics.exec_max, delta_exec));
+
+	curr->se.sum_exec_runtime += delta_exec;
+	account_group_exec_runtime(curr, delta_exec);
+
+	curr->se.exec_start = rq->clock_task;
+	cpuacct_charge(curr, delta_exec);
+
+	sched_rt_avg_update(rq, delta_exec);
+
+	if (!rt_bandwidth_enabled())
+		return;
+
+	for_each_sched_rt_entity(rt_se) {
+		rt_rq = rt_rq_of_se(rt_se);
+
+		if (sched_rt_runtime(rt_rq) != RUNTIME_INF) {
+			raw_spin_lock(&rt_rq->rt_runtime_lock);
+			rt_rq->rt_time += delta_exec;
+			if (sched_rt_runtime_exceeded(rt_rq))
+				resched_task(curr);
+			raw_spin_unlock(&rt_rq->rt_runtime_lock);
+		}
+	}
+}
+
+#if defined CONFIG_SMP
+
+static void
+inc_rt_prio_smp(struct rt_rq *rt_rq, int prio, int prev_prio)
+{
+	struct rq *rq = rq_of_rt_rq(rt_rq);
+
+	if (rq->online && prio < prev_prio)
+		cpupri_set(&rq->rd->cpupri, rq->cpu, prio);
+}
+
+static void
+dec_rt_prio_smp(struct rt_rq *rt_rq, int prio, int prev_prio)
+{
+	struct rq *rq = rq_of_rt_rq(rt_rq);
+
+	if (rq->online && rt_rq->highest_prio.curr != prev_prio)
+		cpupri_set(&rq->rd->cpupri, rq->cpu, rt_rq->highest_prio.curr);
+}
+
+#else /* CONFIG_SMP */
+
+static inline
+void inc_rt_prio_smp(struct rt_rq *rt_rq, int prio, int prev_prio) {}
+static inline
+void dec_rt_prio_smp(struct rt_rq *rt_rq, int prio, int prev_prio) {}
+
+#endif /* CONFIG_SMP */
+
+#if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
+static void
+inc_rt_prio(struct rt_rq *rt_rq, int prio)
+{
+	int prev_prio = rt_rq->highest_prio.curr;
+
+	if (prio < prev_prio)
+		rt_rq->highest_prio.curr = prio;
+
+	inc_rt_prio_smp(rt_rq, prio, prev_prio);
+}
+
+static void
+dec_rt_prio(struct rt_rq *rt_rq, int prio)
+{
+	int prev_prio = rt_rq->highest_prio.curr;
+
+	if (rt_rq->rt_nr_running) {
+
+		WARN_ON(prio < prev_prio);
+
+		/*
+		 * This may have been our highest task, and therefore
+		 * we may have some recomputation to do
+		 */
+		if (prio == prev_prio) {
+			struct rt_prio_array *array = &rt_rq->active;
+
+			rt_rq->highest_prio.curr =
+				sched_find_first_bit(array->bitmap);
+		}
+
+	} else
+		rt_rq->highest_prio.curr = MAX_RT_PRIO;
+
+	dec_rt_prio_smp(rt_rq, prio, prev_prio);
+}
+
+#else
+
+static inline void inc_rt_prio(struct rt_rq *rt_rq, int prio) {}
+static inline void dec_rt_prio(struct rt_rq *rt_rq, int prio) {}
+
+#endif /* CONFIG_SMP || CONFIG_RT_GROUP_SCHED */
+
+#ifdef CONFIG_RT_GROUP_SCHED
+
+static void
+inc_rt_group(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
+{
+	if (rt_se_boosted(rt_se))
+		rt_rq->rt_nr_boosted++;
+
+	if (rt_rq->tg)
+		start_rt_bandwidth(&rt_rq->tg->rt_bandwidth);
+}
+
+static void
+dec_rt_group(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
+{
+	if (rt_se_boosted(rt_se))
+		rt_rq->rt_nr_boosted--;
+
+	WARN_ON(!rt_rq->rt_nr_running && rt_rq->rt_nr_boosted);
+}
+
+#else /* CONFIG_RT_GROUP_SCHED */
+
+static void
+inc_rt_group(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
+{
+	start_rt_bandwidth(&def_rt_bandwidth);
+}
+
+static inline
+void dec_rt_group(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq) {}
+
+#endif /* CONFIG_RT_GROUP_SCHED */
+
+static inline
+void inc_rt_tasks(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
+{
+	int prio = rt_se_prio(rt_se);
+
+	WARN_ON(!rt_prio(prio));
+	rt_rq->rt_nr_running++;
+
+	inc_rt_prio(rt_rq, prio);
+	inc_rt_migration(rt_se, rt_rq);
+	inc_rt_group(rt_se, rt_rq);
+}
+
+static inline
+void dec_rt_tasks(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
+{
+	WARN_ON(!rt_prio(rt_se_prio(rt_se)));
+	WARN_ON(!rt_rq->rt_nr_running);
+	rt_rq->rt_nr_running--;
+
+	dec_rt_prio(rt_rq, rt_se_prio(rt_se));
+	dec_rt_migration(rt_se, rt_rq);
+	dec_rt_group(rt_se, rt_rq);
+}
+
+static void __enqueue_rt_entity(struct sched_rt_entity *rt_se, bool head)
+{
+	struct rt_rq *rt_rq = rt_rq_of_se(rt_se);
+	struct rt_prio_array *array = &rt_rq->active;
+	struct rt_rq *group_rq = group_rt_rq(rt_se);
+	struct list_head *queue = array->queue + rt_se_prio(rt_se);
+
+	/*
+	 * Don't enqueue the group if its throttled, or when empty.
+	 * The latter is a consequence of the former when a child group
+	 * get throttled and the current group doesn't have any other
+	 * active members.
+	 */
+	if (group_rq && (rt_rq_throttled(group_rq) || !group_rq->rt_nr_running))
+		return;
+
+	if (!rt_rq->rt_nr_running)
+		list_add_leaf_rt_rq(rt_rq);
+
+	if (head)
+		list_add(&rt_se->run_list, queue);
+	else
+		list_add_tail(&rt_se->run_list, queue);
+	__set_bit(rt_se_prio(rt_se), array->bitmap);
+
+	inc_rt_tasks(rt_se, rt_rq);
+}
+
+static void __dequeue_rt_entity(struct sched_rt_entity *rt_se)
+{
+	struct rt_rq *rt_rq = rt_rq_of_se(rt_se);
+	struct rt_prio_array *array = &rt_rq->active;
+
+	list_del_init(&rt_se->run_list);
+	if (list_empty(array->queue + rt_se_prio(rt_se)))
+		__clear_bit(rt_se_prio(rt_se), array->bitmap);
+
+	dec_rt_tasks(rt_se, rt_rq);
+	if (!rt_rq->rt_nr_running)
+		list_del_leaf_rt_rq(rt_rq);
+}
+
+/*
+ * Because the prio of an upper entry depends on the lower
+ * entries, we must remove entries top - down.
+ */
+static void dequeue_rt_stack(struct sched_rt_entity *rt_se)
+{
+	struct sched_rt_entity *back = NULL;
+
+	for_each_sched_rt_entity(rt_se) {
+		rt_se->back = back;
+		back = rt_se;
+	}
+
+	for (rt_se = back; rt_se; rt_se = rt_se->back) {
+		if (on_rt_rq(rt_se))
+			__dequeue_rt_entity(rt_se);
+	}
+}
+
+static void enqueue_rt_entity(struct sched_rt_entity *rt_se, bool head)
+{
+	dequeue_rt_stack(rt_se);
+	for_each_sched_rt_entity(rt_se)
+		__enqueue_rt_entity(rt_se, head);
+}
+
+static void dequeue_rt_entity(struct sched_rt_entity *rt_se)
+{
+	dequeue_rt_stack(rt_se);
+
+	for_each_sched_rt_entity(rt_se) {
+		struct rt_rq *rt_rq = group_rt_rq(rt_se);
+
+		if (rt_rq && rt_rq->rt_nr_running)
+			__enqueue_rt_entity(rt_se, false);
+	}
+}
+
+/*
+ * Adding/removing a task to/from a priority array:
+ */
+static void
+enqueue_task_rt(struct rq *rq, struct task_struct *p, int flags)
+{
+	struct sched_rt_entity *rt_se = &p->rt;
+
+	if (flags & ENQUEUE_WAKEUP)
+		rt_se->timeout = 0;
+
+	enqueue_rt_entity(rt_se, flags & ENQUEUE_HEAD);
+
+	if (!task_current(rq, p) && p->rt.nr_cpus_allowed > 1)
+		enqueue_pushable_task(rq, p);
+
+	inc_nr_running(rq);
+}
+
+static void dequeue_task_rt(struct rq *rq, struct task_struct *p, int flags)
+{
+	struct sched_rt_entity *rt_se = &p->rt;
+
+	update_curr_rt(rq);
+	dequeue_rt_entity(rt_se);
+
+	dequeue_pushable_task(rq, p);
+
+	dec_nr_running(rq);
+}
+
+/*
+ * Put task to the head or the end of the run list without the overhead of
+ * dequeue followed by enqueue.
+ */
+static void
+requeue_rt_entity(struct rt_rq *rt_rq, struct sched_rt_entity *rt_se, int head)
+{
+	if (on_rt_rq(rt_se)) {
+		struct rt_prio_array *array = &rt_rq->active;
+		struct list_head *queue = array->queue + rt_se_prio(rt_se);
+
+		if (head)
+			list_move(&rt_se->run_list, queue);
+		else
+			list_move_tail(&rt_se->run_list, queue);
+	}
+}
+
+static void requeue_task_rt(struct rq *rq, struct task_struct *p, int head)
+{
+	struct sched_rt_entity *rt_se = &p->rt;
+	struct rt_rq *rt_rq;
+
+	for_each_sched_rt_entity(rt_se) {
+		rt_rq = rt_rq_of_se(rt_se);
+		requeue_rt_entity(rt_rq, rt_se, head);
+	}
+}
+
+static void yield_task_rt(struct rq *rq)
+{
+	requeue_task_rt(rq, rq->curr, 0);
+}
+
+#ifdef CONFIG_SMP
+static int find_lowest_rq(struct task_struct *task);
+
+static int
+select_task_rq_rt(struct task_struct *p, int sd_flag, int flags)
+{
+	struct task_struct *curr;
+	struct rq *rq;
+	int cpu;
+
+	cpu = task_cpu(p);
+
+	if (p->rt.nr_cpus_allowed == 1)
+		goto out;
+
+	/* For anything but wake ups, just return the task_cpu */
+	if (sd_flag != SD_BALANCE_WAKE && sd_flag != SD_BALANCE_FORK)
+		goto out;
+
+	rq = cpu_rq(cpu);
+
+	rcu_read_lock();
+	curr = ACCESS_ONCE(rq->curr); /* unlocked access */
+
+	/*
+	 * If the current task on @p's runqueue is an RT task, then
+	 * try to see if we can wake this RT task up on another
+	 * runqueue. Otherwise simply start this RT task
+	 * on its current runqueue.
+	 *
+	 * We want to avoid overloading runqueues. If the woken
+	 * task is a higher priority, then it will stay on this CPU
+	 * and the lower prio task should be moved to another CPU.
+	 * Even though this will probably make the lower prio task
+	 * lose its cache, we do not want to bounce a higher task
+	 * around just because it gave up its CPU, perhaps for a
+	 * lock?
+	 *
+	 * For equal prio tasks, we just let the scheduler sort it out.
+	 *
+	 * Otherwise, just let it ride on the affined RQ and the
+	 * post-schedule router will push the preempted task away
+	 *
+	 * This test is optimistic, if we get it wrong the load-balancer
+	 * will have to sort it out.
+	 */
+	if (curr && unlikely(rt_task(curr)) &&
+	    (curr->rt.nr_cpus_allowed < 2 ||
+	     curr->prio <= p->prio) &&
+	    (p->rt.nr_cpus_allowed > 1)) {
+		int target = find_lowest_rq(p);
+
+		if (target != -1)
+			cpu = target;
+	}
+	rcu_read_unlock();
+
+out:
+	return cpu;
+}
+
+static void check_preempt_equal_prio(struct rq *rq, struct task_struct *p)
+{
+	if (rq->curr->rt.nr_cpus_allowed == 1)
+		return;
+
+	if (p->rt.nr_cpus_allowed != 1
+	    && cpupri_find(&rq->rd->cpupri, p, NULL))
+		return;
+
+	if (!cpupri_find(&rq->rd->cpupri, rq->curr, NULL))
+		return;
+
+	/*
+	 * There appears to be other cpus that can accept
+	 * current and none to run 'p', so lets reschedule
+	 * to try and push current away:
+	 */
+	requeue_task_rt(rq, p, 1);
+	resched_task(rq->curr);
+}
+
+#endif /* CONFIG_SMP */
+
+/*
+ * Preempt the current task with a newly woken task if needed:
+ */
+static void check_preempt_curr_rt(struct rq *rq, struct task_struct *p, int flags)
+{
+	if (p->prio < rq->curr->prio) {
+		resched_task(rq->curr);
+		return;
+	}
+
+#ifdef CONFIG_SMP
+	/*
+	 * If:
+	 *
+	 * - the newly woken task is of equal priority to the current task
+	 * - the newly woken task is non-migratable while current is migratable
+	 * - current will be preempted on the next reschedule
+	 *
+	 * we should check to see if current can readily move to a different
+	 * cpu.  If so, we will reschedule to allow the push logic to try
+	 * to move current somewhere else, making room for our non-migratable
+	 * task.
+	 */
+	if (p->prio == rq->curr->prio && !test_tsk_need_resched(rq->curr))
+		check_preempt_equal_prio(rq, p);
+#endif
+}
+
+static struct sched_rt_entity *pick_next_rt_entity(struct rq *rq,
+						   struct rt_rq *rt_rq)
+{
+	struct rt_prio_array *array = &rt_rq->active;
+	struct sched_rt_entity *next = NULL;
+	struct list_head *queue;
+	int idx;
+
+	idx = sched_find_first_bit(array->bitmap);
+	BUG_ON(idx >= MAX_RT_PRIO);
+
+	queue = array->queue + idx;
+	next = list_entry(queue->next, struct sched_rt_entity, run_list);
+
+	return next;
+}
+
+static struct task_struct *_pick_next_task_rt(struct rq *rq)
+{
+	struct sched_rt_entity *rt_se;
+	struct task_struct *p;
+	struct rt_rq *rt_rq;
+
+	rt_rq = &rq->rt;
+
+	if (!rt_rq->rt_nr_running)
+		return NULL;
+
+	if (rt_rq_throttled(rt_rq))
+		return NULL;
+
+	do {
+		rt_se = pick_next_rt_entity(rq, rt_rq);
+		BUG_ON(!rt_se);
+		rt_rq = group_rt_rq(rt_se);
+	} while (rt_rq);
+
+	p = rt_task_of(rt_se);
+	p->se.exec_start = rq->clock_task;
+
+	return p;
+}
+
+static struct task_struct *pick_next_task_rt(struct rq *rq)
+{
+	struct task_struct *p = _pick_next_task_rt(rq);
+
+	/* The running task is never eligible for pushing */
+	if (p)
+		dequeue_pushable_task(rq, p);
+
+#ifdef CONFIG_SMP
+	/*
+	 * We detect this state here so that we can avoid taking the RQ
+	 * lock again later if there is no need to push
+	 */
+	rq->post_schedule = has_pushable_tasks(rq);
+#endif
+
+	return p;
+}
+
+static void put_prev_task_rt(struct rq *rq, struct task_struct *p)
+{
+	update_curr_rt(rq);
+
+	/*
+	 * The previous task needs to be made eligible for pushing
+	 * if it is still active
+	 */
+	if (on_rt_rq(&p->rt) && p->rt.nr_cpus_allowed > 1)
+		enqueue_pushable_task(rq, p);
+}
+
+#ifdef CONFIG_SMP
+
+/* Only try algorithms three times */
+#define RT_MAX_TRIES 3
+
+static int pick_rt_task(struct rq *rq, struct task_struct *p, int cpu)
+{
+	if (!task_running(rq, p) &&
+	    (cpu < 0 || cpumask_test_cpu(cpu, tsk_cpus_allowed(p))) &&
+	    (p->rt.nr_cpus_allowed > 1))
+		return 1;
+	return 0;
+}
+
+/* Return the second highest RT task, NULL otherwise */
+static struct task_struct *pick_next_highest_task_rt(struct rq *rq, int cpu)
+{
+	struct task_struct *next = NULL;
+	struct sched_rt_entity *rt_se;
+	struct rt_prio_array *array;
+	struct rt_rq *rt_rq;
+	int idx;
+
+	for_each_leaf_rt_rq(rt_rq, rq) {
+		array = &rt_rq->active;
+		idx = sched_find_first_bit(array->bitmap);
+next_idx:
+		if (idx >= MAX_RT_PRIO)
+			continue;
+		if (next && next->prio < idx)
+			continue;
+		list_for_each_entry(rt_se, array->queue + idx, run_list) {
+			struct task_struct *p;
+
+			if (!rt_entity_is_task(rt_se))
+				continue;
+
+			p = rt_task_of(rt_se);
+			if (pick_rt_task(rq, p, cpu)) {
+				next = p;
+				break;
+			}
+		}
+		if (!next) {
+			idx = find_next_bit(array->bitmap, MAX_RT_PRIO, idx+1);
+			goto next_idx;
+		}
+	}
+
+	return next;
+}
+
+static DEFINE_PER_CPU(cpumask_var_t, local_cpu_mask);
+
+static int find_lowest_rq(struct task_struct *task)
+{
+	struct sched_domain *sd;
+	struct cpumask *lowest_mask = __get_cpu_var(local_cpu_mask);
+	int this_cpu = smp_processor_id();
+	int cpu      = task_cpu(task);
+
+	/* Make sure the mask is initialized first */
+	if (unlikely(!lowest_mask))
+		return -1;
+
+	if (task->rt.nr_cpus_allowed == 1)
+		return -1; /* No other targets possible */
+
+	if (!cpupri_find(&task_rq(task)->rd->cpupri, task, lowest_mask))
+		return -1; /* No targets found */
+
+	/*
+	 * At this point we have built a mask of cpus representing the
+	 * lowest priority tasks in the system.  Now we want to elect
+	 * the best one based on our affinity and topology.
+	 *
+	 * We prioritize the last cpu that the task executed on since
+	 * it is most likely cache-hot in that location.
+	 */
+	if (cpumask_test_cpu(cpu, lowest_mask))
+		return cpu;
+
+	/*
+	 * Otherwise, we consult the sched_domains span maps to figure
+	 * out which cpu is logically closest to our hot cache data.
+	 */
+	if (!cpumask_test_cpu(this_cpu, lowest_mask))
+		this_cpu = -1; /* Skip this_cpu opt if not among lowest */
+
+	rcu_read_lock();
+	for_each_domain(cpu, sd) {
+		if (sd->flags & SD_WAKE_AFFINE) {
+			int best_cpu;
+
+			/*
+			 * "this_cpu" is cheaper to preempt than a
+			 * remote processor.
+			 */
+			if (this_cpu != -1 &&
+			    cpumask_test_cpu(this_cpu, sched_domain_span(sd))) {
+				rcu_read_unlock();
+				return this_cpu;
+			}
+
+			best_cpu = cpumask_first_and(lowest_mask,
+						     sched_domain_span(sd));
+			if (best_cpu < nr_cpu_ids) {
+				rcu_read_unlock();
+				return best_cpu;
+			}
+		}
+	}
+	rcu_read_unlock();
+
+	/*
+	 * And finally, if there were no matches within the domains
+	 * just give the caller *something* to work with from the compatible
+	 * locations.
+	 */
+	if (this_cpu != -1)
+		return this_cpu;
+
+	cpu = cpumask_any(lowest_mask);
+	if (cpu < nr_cpu_ids)
+		return cpu;
+	return -1;
+}
+
+/* Will lock the rq it finds */
+static struct rq *find_lock_lowest_rq(struct task_struct *task, struct rq *rq)
+{
+	struct rq *lowest_rq = NULL;
+	int tries;
+	int cpu;
+
+	for (tries = 0; tries < RT_MAX_TRIES; tries++) {
+		cpu = find_lowest_rq(task);
+
+		if ((cpu == -1) || (cpu == rq->cpu))
+			break;
+
+		lowest_rq = cpu_rq(cpu);
+
+		/* if the prio of this runqueue changed, try again */
+		if (double_lock_balance(rq, lowest_rq)) {
+			/*
+			 * We had to unlock the run queue. In
+			 * the mean time, task could have
+			 * migrated already or had its affinity changed.
+			 * Also make sure that it wasn't scheduled on its rq.
+			 */
+			if (unlikely(task_rq(task) != rq ||
+				     !cpumask_test_cpu(lowest_rq->cpu,
+						       tsk_cpus_allowed(task)) ||
+				     task_running(rq, task) ||
+				     !task->on_rq)) {
+
+				raw_spin_unlock(&lowest_rq->lock);
+				lowest_rq = NULL;
+				break;
+			}
+		}
+
+		/* If this rq is still suitable use it. */
+		if (lowest_rq->rt.highest_prio.curr > task->prio)
+			break;
+
+		/* try again */
+		double_unlock_balance(rq, lowest_rq);
+		lowest_rq = NULL;
+	}
+
+	return lowest_rq;
+}
+
+static struct task_struct *pick_next_pushable_task(struct rq *rq)
+{
+	struct task_struct *p;
+
+	if (!has_pushable_tasks(rq))
+		return NULL;
+
+	p = plist_first_entry(&rq->rt.pushable_tasks,
+			      struct task_struct, pushable_tasks);
+
+	BUG_ON(rq->cpu != task_cpu(p));
+	BUG_ON(task_current(rq, p));
+	BUG_ON(p->rt.nr_cpus_allowed <= 1);
+
+	BUG_ON(!p->on_rq);
+	BUG_ON(!rt_task(p));
+
+	return p;
+}
+
+/*
+ * If the current CPU has more than one RT task, see if the non
+ * running task can migrate over to a CPU that is running a task
+ * of lesser priority.
+ */
+static int push_rt_task(struct rq *rq)
+{
+	struct task_struct *next_task;
+	struct rq *lowest_rq;
+	int ret = 0;
+
+	if (!rq->rt.overloaded)
+		return 0;
+
+	next_task = pick_next_pushable_task(rq);
+	if (!next_task)
+		return 0;
+
+retry:
+	if (unlikely(next_task == rq->curr)) {
+		WARN_ON(1);
+		return 0;
+	}
+
+	/*
+	 * It's possible that the next_task slipped in of
+	 * higher priority than current. If that's the case
+	 * just reschedule current.
+	 */
+	if (unlikely(next_task->prio < rq->curr->prio)) {
+		resched_task(rq->curr);
+		return 0;
+	}
+
+	/* We might release rq lock */
+	get_task_struct(next_task);
+
+	/* find_lock_lowest_rq locks the rq if found */
+	lowest_rq = find_lock_lowest_rq(next_task, rq);
+	if (!lowest_rq) {
+		struct task_struct *task;
+		/*
+		 * find_lock_lowest_rq releases rq->lock
+		 * so it is possible that next_task has migrated.
+		 *
+		 * We need to make sure that the task is still on the same
+		 * run-queue and is also still the next task eligible for
+		 * pushing.
+		 */
+		task = pick_next_pushable_task(rq);
+		if (task_cpu(next_task) == rq->cpu && task == next_task) {
+			/*
+			 * The task hasn't migrated, and is still the next
+			 * eligible task, but we failed to find a run-queue
+			 * to push it to.  Do not retry in this case, since
+			 * other cpus will pull from us when ready.
+			 */
+			goto out;
+		}
+
+		if (!task)
+			/* No more tasks, just exit */
+			goto out;
+
+		/*
+		 * Something has shifted, try again.
+		 */
+		put_task_struct(next_task);
+		next_task = task;
+		goto retry;
+	}
+
+	deactivate_task(rq, next_task, 0);
+	set_task_cpu(next_task, lowest_rq->cpu);
+	activate_task(lowest_rq, next_task, 0);
+	ret = 1;
+
+	resched_task(lowest_rq->curr);
+
+	double_unlock_balance(rq, lowest_rq);
+
+out:
+	put_task_struct(next_task);
+
+	return ret;
+}
+
+static void push_rt_tasks(struct rq *rq)
+{
+	/* push_rt_task will return true if it moved an RT */
+	while (push_rt_task(rq))
+		;
+}
+
+static int pull_rt_task(struct rq *this_rq)
+{
+	int this_cpu = this_rq->cpu, ret = 0, cpu;
+	struct task_struct *p;
+	struct rq *src_rq;
+
+	if (likely(!rt_overloaded(this_rq)))
+		return 0;
+
+	for_each_cpu(cpu, this_rq->rd->rto_mask) {
+		if (this_cpu == cpu)
+			continue;
+
+		src_rq = cpu_rq(cpu);
+
+		/*
+		 * Don't bother taking the src_rq->lock if the next highest
+		 * task is known to be lower-priority than our current task.
+		 * This may look racy, but if this value is about to go
+		 * logically higher, the src_rq will push this task away.
+		 * And if its going logically lower, we do not care
+		 */
+		if (src_rq->rt.highest_prio.next >=
+		    this_rq->rt.highest_prio.curr)
+			continue;
+
+		/*
+		 * We can potentially drop this_rq's lock in
+		 * double_lock_balance, and another CPU could
+		 * alter this_rq
+		 */
+		double_lock_balance(this_rq, src_rq);
+
+		/*
+		 * Are there still pullable RT tasks?
+		 */
+		if (src_rq->rt.rt_nr_running <= 1)
+			goto skip;
+
+		p = pick_next_highest_task_rt(src_rq, this_cpu);
+
+		/*
+		 * Do we have an RT task that preempts
+		 * the to-be-scheduled task?
+		 */
+		if (p && (p->prio < this_rq->rt.highest_prio.curr)) {
+			WARN_ON(p == src_rq->curr);
+			WARN_ON(!p->on_rq);
+
+			/*
+			 * There's a chance that p is higher in priority
+			 * than what's currently running on its cpu.
+			 * This is just that p is wakeing up and hasn't
+			 * had a chance to schedule. We only pull
+			 * p if it is lower in priority than the
+			 * current task on the run queue
+			 */
+			if (p->prio < src_rq->curr->prio)
+				goto skip;
+
+			ret = 1;
+
+			deactivate_task(src_rq, p, 0);
+			set_task_cpu(p, this_cpu);
+			activate_task(this_rq, p, 0);
+			/*
+			 * We continue with the search, just in
+			 * case there's an even higher prio task
+			 * in another runqueue. (low likelihood
+			 * but possible)
+			 */
+		}
+skip:
+		double_unlock_balance(this_rq, src_rq);
+	}
+
+	return ret;
+}
+
+static void pre_schedule_rt(struct rq *rq, struct task_struct *prev)
+{
+	/* Try to pull RT tasks here if we lower this rq's prio */
+	if (rq->rt.highest_prio.curr > prev->prio)
+		pull_rt_task(rq);
+}
+
+static void post_schedule_rt(struct rq *rq)
+{
+	push_rt_tasks(rq);
+}
+
+/*
+ * If we are not running and we are not going to reschedule soon, we should
+ * try to push tasks away now
+ */
+static void task_woken_rt(struct rq *rq, struct task_struct *p)
+{
+	if (!task_running(rq, p) &&
+	    !test_tsk_need_resched(rq->curr) &&
+	    has_pushable_tasks(rq) &&
+	    p->rt.nr_cpus_allowed > 1 &&
+	    rt_task(rq->curr) &&
+	    (rq->curr->rt.nr_cpus_allowed < 2 ||
+	     rq->curr->prio <= p->prio))
+		push_rt_tasks(rq);
+}
+
+static void set_cpus_allowed_rt(struct task_struct *p,
+				const struct cpumask *new_mask)
+{
+	int weight = cpumask_weight(new_mask);
+
+	BUG_ON(!rt_task(p));
+
+	/*
+	 * Update the migration status of the RQ if we have an RT task
+	 * which is running AND changing its weight value.
+	 */
+	if (p->on_rq && (weight != p->rt.nr_cpus_allowed)) {
+		struct rq *rq = task_rq(p);
+
+		if (!task_current(rq, p)) {
+			/*
+			 * Make sure we dequeue this task from the pushable list
+			 * before going further.  It will either remain off of
+			 * the list because we are no longer pushable, or it
+			 * will be requeued.
+			 */
+			if (p->rt.nr_cpus_allowed > 1)
+				dequeue_pushable_task(rq, p);
+
+			/*
+			 * Requeue if our weight is changing and still > 1
+			 */
+			if (weight > 1)
+				enqueue_pushable_task(rq, p);
+
+		}
+
+		if ((p->rt.nr_cpus_allowed <= 1) && (weight > 1)) {
+			rq->rt.rt_nr_migratory++;
+		} else if ((p->rt.nr_cpus_allowed > 1) && (weight <= 1)) {
+			BUG_ON(!rq->rt.rt_nr_migratory);
+			rq->rt.rt_nr_migratory--;
+		}
+
+		update_rt_migration(&rq->rt);
+	}
+}
+
+/* Assumes rq->lock is held */
+static void rq_online_rt(struct rq *rq)
+{
+	if (rq->rt.overloaded)
+		rt_set_overload(rq);
+
+	__enable_runtime(rq);
+
+	cpupri_set(&rq->rd->cpupri, rq->cpu, rq->rt.highest_prio.curr);
+}
+
+/* Assumes rq->lock is held */
+static void rq_offline_rt(struct rq *rq)
+{
+	if (rq->rt.overloaded)
+		rt_clear_overload(rq);
+
+	__disable_runtime(rq);
+
+	cpupri_set(&rq->rd->cpupri, rq->cpu, CPUPRI_INVALID);
+}
+
+/*
+ * When switch from the rt queue, we bring ourselves to a position
+ * that we might want to pull RT tasks from other runqueues.
+ */
+static void switched_from_rt(struct rq *rq, struct task_struct *p)
+{
+	/*
+	 * If there are other RT tasks then we will reschedule
+	 * and the scheduling of the other RT tasks will handle
+	 * the balancing. But if we are the last RT task
+	 * we may need to handle the pulling of RT tasks
+	 * now.
+	 */
+	if (p->on_rq && !rq->rt.rt_nr_running)
+		pull_rt_task(rq);
+}
+
+void init_sched_rt_class(void)
+{
+	unsigned int i;
+
+	for_each_possible_cpu(i) {
+		zalloc_cpumask_var_node(&per_cpu(local_cpu_mask, i),
+					GFP_KERNEL, cpu_to_node(i));
+	}
+}
+#endif /* CONFIG_SMP */
+
+/*
+ * When switching a task to RT, we may overload the runqueue
+ * with RT tasks. In this case we try to push them off to
+ * other runqueues.
+ */
+static void switched_to_rt(struct rq *rq, struct task_struct *p)
+{
+	int check_resched = 1;
+
+	/*
+	 * If we are already running, then there's nothing
+	 * that needs to be done. But if we are not running
+	 * we may need to preempt the current running task.
+	 * If that current running task is also an RT task
+	 * then see if we can move to another run queue.
+	 */
+	if (p->on_rq && rq->curr != p) {
+#ifdef CONFIG_SMP
+		if (rq->rt.overloaded && push_rt_task(rq) &&
+		    /* Don't resched if we changed runqueues */
+		    rq != task_rq(p))
+			check_resched = 0;
+#endif /* CONFIG_SMP */
+		if (check_resched && p->prio < rq->curr->prio)
+			resched_task(rq->curr);
+	}
+}
+
+/*
+ * Priority of the task has changed. This may cause
+ * us to initiate a push or pull.
+ */
+static void
+prio_changed_rt(struct rq *rq, struct task_struct *p, int oldprio)
+{
+	if (!p->on_rq)
+		return;
+
+	if (rq->curr == p) {
+#ifdef CONFIG_SMP
+		/*
+		 * If our priority decreases while running, we
+		 * may need to pull tasks to this runqueue.
+		 */
+		if (oldprio < p->prio)
+			pull_rt_task(rq);
+		/*
+		 * If there's a higher priority task waiting to run
+		 * then reschedule. Note, the above pull_rt_task
+		 * can release the rq lock and p could migrate.
+		 * Only reschedule if p is still on the same runqueue.
+		 */
+		if (p->prio > rq->rt.highest_prio.curr && rq->curr == p)
+			resched_task(p);
+#else
+		/* For UP simply resched on drop of prio */
+		if (oldprio < p->prio)
+			resched_task(p);
+#endif /* CONFIG_SMP */
+	} else {
+		/*
+		 * This task is not running, but if it is
+		 * greater than the current running task
+		 * then reschedule.
+		 */
+		if (p->prio < rq->curr->prio)
+			resched_task(rq->curr);
+	}
+}
+
+static void watchdog(struct rq *rq, struct task_struct *p)
+{
+	unsigned long soft, hard;
+
+	/* max may change after cur was read, this will be fixed next tick */
+	soft = task_rlimit(p, RLIMIT_RTTIME);
+	hard = task_rlimit_max(p, RLIMIT_RTTIME);
+
+	if (soft != RLIM_INFINITY) {
+		unsigned long next;
+
+		p->rt.timeout++;
+		next = DIV_ROUND_UP(min(soft, hard), USEC_PER_SEC/HZ);
+		if (p->rt.timeout > next)
+			p->cputime_expires.sched_exp = p->se.sum_exec_runtime;
+	}
+}
+
+static void task_tick_rt(struct rq *rq, struct task_struct *p, int queued)
+{
+	update_curr_rt(rq);
+
+	watchdog(rq, p);
+
+	/*
+	 * RR tasks need a special form of timeslice management.
+	 * FIFO tasks have no timeslices.
+	 */
+	if (p->policy != SCHED_RR)
+		return;
+
+	if (--p->rt.time_slice)
+		return;
+
+	p->rt.time_slice = DEF_TIMESLICE;
+
+	/*
+	 * Requeue to the end of queue if we are not the only element
+	 * on the queue:
+	 */
+	if (p->rt.run_list.prev != p->rt.run_list.next) {
+		requeue_task_rt(rq, p, 0);
+		set_tsk_need_resched(p);
+	}
+}
+
+static void set_curr_task_rt(struct rq *rq)
+{
+	struct task_struct *p = rq->curr;
+
+	p->se.exec_start = rq->clock_task;
+
+	/* The running task is never eligible for pushing */
+	dequeue_pushable_task(rq, p);
+}
+
+static unsigned int get_rr_interval_rt(struct rq *rq, struct task_struct *task)
+{
+	/*
+	 * Time slice is 0 for SCHED_FIFO tasks
+	 */
+	if (task->policy == SCHED_RR)
+		return DEF_TIMESLICE;
+	else
+		return 0;
+}
+
+const struct sched_class rt_sched_class = {
+	.next			= &fair_sched_class,
+	.enqueue_task		= enqueue_task_rt,
+	.dequeue_task		= dequeue_task_rt,
+	.yield_task		= yield_task_rt,
+
+	.check_preempt_curr	= check_preempt_curr_rt,
+
+	.pick_next_task		= pick_next_task_rt,
+	.put_prev_task		= put_prev_task_rt,
+
+#ifdef CONFIG_SMP
+	.select_task_rq		= select_task_rq_rt,
+
+	.set_cpus_allowed       = set_cpus_allowed_rt,
+	.rq_online              = rq_online_rt,
+	.rq_offline             = rq_offline_rt,
+	.pre_schedule		= pre_schedule_rt,
+	.post_schedule		= post_schedule_rt,
+	.task_woken		= task_woken_rt,
+	.switched_from		= switched_from_rt,
+#endif
+
+	.set_curr_task          = set_curr_task_rt,
+	.task_tick		= task_tick_rt,
+
+	.get_rr_interval	= get_rr_interval_rt,
+
+	.prio_changed		= prio_changed_rt,
+	.switched_to		= switched_to_rt,
+};
+
+#ifdef CONFIG_SCHED_DEBUG
+extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
+
+void print_rt_stats(struct seq_file *m, int cpu)
+{
+	rt_rq_iter_t iter;
+	struct rt_rq *rt_rq;
+
+	rcu_read_lock();
+	for_each_rt_rq(rt_rq, iter, cpu_rq(cpu))
+		print_rt_rq(m, cpu, rt_rq);
+	rcu_read_unlock();
+}
+#endif /* CONFIG_SCHED_DEBUG */
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
new file mode 100644
index 00000000000..98c0c2623db
--- /dev/null
+++ b/kernel/sched/sched.h
@@ -0,0 +1,1166 @@
+
+#include <linux/sched.h>
+#include <linux/mutex.h>
+#include <linux/spinlock.h>
+#include <linux/stop_machine.h>
+
+#include "cpupri.h"
+
+extern __read_mostly int scheduler_running;
+
+/*
+ * Convert user-nice values [ -20 ... 0 ... 19 ]
+ * to static priority [ MAX_RT_PRIO..MAX_PRIO-1 ],
+ * and back.
+ */
+#define NICE_TO_PRIO(nice)	(MAX_RT_PRIO + (nice) + 20)
+#define PRIO_TO_NICE(prio)	((prio) - MAX_RT_PRIO - 20)
+#define TASK_NICE(p)		PRIO_TO_NICE((p)->static_prio)
+
+/*
+ * 'User priority' is the nice value converted to something we
+ * can work with better when scaling various scheduler parameters,
+ * it's a [ 0 ... 39 ] range.
+ */
+#define USER_PRIO(p)		((p)-MAX_RT_PRIO)
+#define TASK_USER_PRIO(p)	USER_PRIO((p)->static_prio)
+#define MAX_USER_PRIO		(USER_PRIO(MAX_PRIO))
+
+/*
+ * Helpers for converting nanosecond timing to jiffy resolution
+ */
+#define NS_TO_JIFFIES(TIME)	((unsigned long)(TIME) / (NSEC_PER_SEC / HZ))
+
+#define NICE_0_LOAD		SCHED_LOAD_SCALE
+#define NICE_0_SHIFT		SCHED_LOAD_SHIFT
+
+/*
+ * These are the 'tuning knobs' of the scheduler:
+ *
+ * default timeslice is 100 msecs (used only for SCHED_RR tasks).
+ * Timeslices get refilled after they expire.
+ */
+#define DEF_TIMESLICE		(100 * HZ / 1000)
+
+/*
+ * single value that denotes runtime == period, ie unlimited time.
+ */
+#define RUNTIME_INF	((u64)~0ULL)
+
+static inline int rt_policy(int policy)
+{
+	if (policy == SCHED_FIFO || policy == SCHED_RR)
+		return 1;
+	return 0;
+}
+
+static inline int task_has_rt_policy(struct task_struct *p)
+{
+	return rt_policy(p->policy);
+}
+
+/*
+ * This is the priority-queue data structure of the RT scheduling class:
+ */
+struct rt_prio_array {
+	DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
+	struct list_head queue[MAX_RT_PRIO];
+};
+
+struct rt_bandwidth {
+	/* nests inside the rq lock: */
+	raw_spinlock_t		rt_runtime_lock;
+	ktime_t			rt_period;
+	u64			rt_runtime;
+	struct hrtimer		rt_period_timer;
+};
+
+extern struct mutex sched_domains_mutex;
+
+#ifdef CONFIG_CGROUP_SCHED
+
+#include <linux/cgroup.h>
+
+struct cfs_rq;
+struct rt_rq;
+
+static LIST_HEAD(task_groups);
+
+struct cfs_bandwidth {
+#ifdef CONFIG_CFS_BANDWIDTH
+	raw_spinlock_t lock;
+	ktime_t period;
+	u64 quota, runtime;
+	s64 hierarchal_quota;
+	u64 runtime_expires;
+
+	int idle, timer_active;
+	struct hrtimer period_timer, slack_timer;
+	struct list_head throttled_cfs_rq;
+
+	/* statistics */
+	int nr_periods, nr_throttled;
+	u64 throttled_time;
+#endif
+};
+
+/* task group related information */
+struct task_group {
+	struct cgroup_subsys_state css;
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+	/* schedulable entities of this group on each cpu */
+	struct sched_entity **se;
+	/* runqueue "owned" by this group on each cpu */
+	struct cfs_rq **cfs_rq;
+	unsigned long shares;
+
+	atomic_t load_weight;
+#endif
+
+#ifdef CONFIG_RT_GROUP_SCHED
+	struct sched_rt_entity **rt_se;
+	struct rt_rq **rt_rq;
+
+	struct rt_bandwidth rt_bandwidth;
+#endif
+
+	struct rcu_head rcu;
+	struct list_head list;
+
+	struct task_group *parent;
+	struct list_head siblings;
+	struct list_head children;
+
+#ifdef CONFIG_SCHED_AUTOGROUP
+	struct autogroup *autogroup;
+#endif
+
+	struct cfs_bandwidth cfs_bandwidth;
+};
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+#define ROOT_TASK_GROUP_LOAD	NICE_0_LOAD
+
+/*
+ * A weight of 0 or 1 can cause arithmetics problems.
+ * A weight of a cfs_rq is the sum of weights of which entities
+ * are queued on this cfs_rq, so a weight of a entity should not be
+ * too large, so as the shares value of a task group.
+ * (The default weight is 1024 - so there's no practical
+ *  limitation from this.)
+ */
+#define MIN_SHARES	(1UL <<  1)
+#define MAX_SHARES	(1UL << 18)
+#endif
+
+/* Default task group.
+ *	Every task in system belong to this group at bootup.
+ */
+extern struct task_group root_task_group;
+
+typedef int (*tg_visitor)(struct task_group *, void *);
+
+extern int walk_tg_tree_from(struct task_group *from,
+			     tg_visitor down, tg_visitor up, void *data);
+
+/*
+ * Iterate the full tree, calling @down when first entering a node and @up when
+ * leaving it for the final time.
+ *
+ * Caller must hold rcu_lock or sufficient equivalent.
+ */
+static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
+{
+	return walk_tg_tree_from(&root_task_group, down, up, data);
+}
+
+extern int tg_nop(struct task_group *tg, void *data);
+
+extern void free_fair_sched_group(struct task_group *tg);
+extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
+extern void unregister_fair_sched_group(struct task_group *tg, int cpu);
+extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
+			struct sched_entity *se, int cpu,
+			struct sched_entity *parent);
+extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
+extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
+
+extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
+extern void __start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
+extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
+
+extern void free_rt_sched_group(struct task_group *tg);
+extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
+extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
+		struct sched_rt_entity *rt_se, int cpu,
+		struct sched_rt_entity *parent);
+
+#else /* CONFIG_CGROUP_SCHED */
+
+struct cfs_bandwidth { };
+
+#endif	/* CONFIG_CGROUP_SCHED */
+
+/* CFS-related fields in a runqueue */
+struct cfs_rq {
+	struct load_weight load;
+	unsigned long nr_running, h_nr_running;
+
+	u64 exec_clock;
+	u64 min_vruntime;
+#ifndef CONFIG_64BIT
+	u64 min_vruntime_copy;
+#endif
+
+	struct rb_root tasks_timeline;
+	struct rb_node *rb_leftmost;
+
+	struct list_head tasks;
+	struct list_head *balance_iterator;
+
+	/*
+	 * 'curr' points to currently running entity on this cfs_rq.
+	 * It is set to NULL otherwise (i.e when none are currently running).
+	 */
+	struct sched_entity *curr, *next, *last, *skip;
+
+#ifdef	CONFIG_SCHED_DEBUG
+	unsigned int nr_spread_over;
+#endif
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+	struct rq *rq;	/* cpu runqueue to which this cfs_rq is attached */
+
+	/*
+	 * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
+	 * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
+	 * (like users, containers etc.)
+	 *
+	 * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a cpu. This
+	 * list is used during load balance.
+	 */
+	int on_list;
+	struct list_head leaf_cfs_rq_list;
+	struct task_group *tg;	/* group that "owns" this runqueue */
+
+#ifdef CONFIG_SMP
+	/*
+	 * the part of load.weight contributed by tasks
+	 */
+	unsigned long task_weight;
+
+	/*
+	 *   h_load = weight * f(tg)
+	 *
+	 * Where f(tg) is the recursive weight fraction assigned to
+	 * this group.
+	 */
+	unsigned long h_load;
+
+	/*
+	 * Maintaining per-cpu shares distribution for group scheduling
+	 *
+	 * load_stamp is the last time we updated the load average
+	 * load_last is the last time we updated the load average and saw load
+	 * load_unacc_exec_time is currently unaccounted execution time
+	 */
+	u64 load_avg;
+	u64 load_period;
+	u64 load_stamp, load_last, load_unacc_exec_time;
+
+	unsigned long load_contribution;
+#endif /* CONFIG_SMP */
+#ifdef CONFIG_CFS_BANDWIDTH
+	int runtime_enabled;
+	u64 runtime_expires;
+	s64 runtime_remaining;
+
+	u64 throttled_timestamp;
+	int throttled, throttle_count;
+	struct list_head throttled_list;
+#endif /* CONFIG_CFS_BANDWIDTH */
+#endif /* CONFIG_FAIR_GROUP_SCHED */
+};
+
+static inline int rt_bandwidth_enabled(void)
+{
+	return sysctl_sched_rt_runtime >= 0;
+}
+
+/* Real-Time classes' related field in a runqueue: */
+struct rt_rq {
+	struct rt_prio_array active;
+	unsigned long rt_nr_running;
+#if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
+	struct {
+		int curr; /* highest queued rt task prio */
+#ifdef CONFIG_SMP
+		int next; /* next highest */
+#endif
+	} highest_prio;
+#endif
+#ifdef CONFIG_SMP
+	unsigned long rt_nr_migratory;
+	unsigned long rt_nr_total;
+	int overloaded;
+	struct plist_head pushable_tasks;
+#endif
+	int rt_throttled;
+	u64 rt_time;
+	u64 rt_runtime;
+	/* Nests inside the rq lock: */
+	raw_spinlock_t rt_runtime_lock;
+
+#ifdef CONFIG_RT_GROUP_SCHED
+	unsigned long rt_nr_boosted;
+
+	struct rq *rq;
+	struct list_head leaf_rt_rq_list;
+	struct task_group *tg;
+#endif
+};
+
+#ifdef CONFIG_SMP
+
+/*
+ * We add the notion of a root-domain which will be used to define per-domain
+ * variables. Each exclusive cpuset essentially defines an island domain by
+ * fully partitioning the member cpus from any other cpuset. Whenever a new
+ * exclusive cpuset is created, we also create and attach a new root-domain
+ * object.
+ *
+ */
+struct root_domain {
+	atomic_t refcount;
+	atomic_t rto_count;
+	struct rcu_head rcu;
+	cpumask_var_t span;
+	cpumask_var_t online;
+
+	/*
+	 * The "RT overload" flag: it gets set if a CPU has more than
+	 * one runnable RT task.
+	 */
+	cpumask_var_t rto_mask;
+	struct cpupri cpupri;
+};
+
+extern struct root_domain def_root_domain;
+
+#endif /* CONFIG_SMP */
+
+/*
+ * This is the main, per-CPU runqueue data structure.
+ *
+ * Locking rule: those places that want to lock multiple runqueues
+ * (such as the load balancing or the thread migration code), lock
+ * acquire operations must be ordered by ascending &runqueue.
+ */
+struct rq {
+	/* runqueue lock: */
+	raw_spinlock_t lock;
+
+	/*
+	 * nr_running and cpu_load should be in the same cacheline because
+	 * remote CPUs use both these fields when doing load calculation.
+	 */
+	unsigned long nr_running;
+	#define CPU_LOAD_IDX_MAX 5
+	unsigned long cpu_load[CPU_LOAD_IDX_MAX];
+	unsigned long last_load_update_tick;
+#ifdef CONFIG_NO_HZ
+	u64 nohz_stamp;
+	unsigned long nohz_flags;
+#endif
+	int skip_clock_update;
+
+	/* capture load from *all* tasks on this cpu: */
+	struct load_weight load;
+	unsigned long nr_load_updates;
+	u64 nr_switches;
+
+	struct cfs_rq cfs;
+	struct rt_rq rt;
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+	/* list of leaf cfs_rq on this cpu: */
+	struct list_head leaf_cfs_rq_list;
+#endif
+#ifdef CONFIG_RT_GROUP_SCHED
+	struct list_head leaf_rt_rq_list;
+#endif
+
+	/*
+	 * This is part of a global counter where only the total sum
+	 * over all CPUs matters. A task can increase this counter on
+	 * one CPU and if it got migrated afterwards it may decrease
+	 * it on another CPU. Always updated under the runqueue lock:
+	 */
+	unsigned long nr_uninterruptible;
+
+	struct task_struct *curr, *idle, *stop;
+	unsigned long next_balance;
+	struct mm_struct *prev_mm;
+
+	u64 clock;
+	u64 clock_task;
+
+	atomic_t nr_iowait;
+
+#ifdef CONFIG_SMP
+	struct root_domain *rd;
+	struct sched_domain *sd;
+
+	unsigned long cpu_power;
+
+	unsigned char idle_balance;
+	/* For active balancing */
+	int post_schedule;
+	int active_balance;
+	int push_cpu;
+	struct cpu_stop_work active_balance_work;
+	/* cpu of this runqueue: */
+	int cpu;
+	int online;
+
+	u64 rt_avg;
+	u64 age_stamp;
+	u64 idle_stamp;
+	u64 avg_idle;
+#endif
+
+#ifdef CONFIG_IRQ_TIME_ACCOUNTING
+	u64 prev_irq_time;
+#endif
+#ifdef CONFIG_PARAVIRT
+	u64 prev_steal_time;
+#endif
+#ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
+	u64 prev_steal_time_rq;
+#endif
+
+	/* calc_load related fields */
+	unsigned long calc_load_update;
+	long calc_load_active;
+
+#ifdef CONFIG_SCHED_HRTICK
+#ifdef CONFIG_SMP
+	int hrtick_csd_pending;
+	struct call_single_data hrtick_csd;
+#endif
+	struct hrtimer hrtick_timer;
+#endif
+
+#ifdef CONFIG_SCHEDSTATS
+	/* latency stats */
+	struct sched_info rq_sched_info;
+	unsigned long long rq_cpu_time;
+	/* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */
+
+	/* sys_sched_yield() stats */
+	unsigned int yld_count;
+
+	/* schedule() stats */
+	unsigned int sched_switch;
+	unsigned int sched_count;
+	unsigned int sched_goidle;
+
+	/* try_to_wake_up() stats */
+	unsigned int ttwu_count;
+	unsigned int ttwu_local;
+#endif
+
+#ifdef CONFIG_SMP
+	struct llist_head wake_list;
+#endif
+};
+
+static inline int cpu_of(struct rq *rq)
+{
+#ifdef CONFIG_SMP
+	return rq->cpu;
+#else
+	return 0;
+#endif
+}
+
+DECLARE_PER_CPU(struct rq, runqueues);
+
+#define cpu_rq(cpu)		(&per_cpu(runqueues, (cpu)))
+#define this_rq()		(&__get_cpu_var(runqueues))
+#define task_rq(p)		cpu_rq(task_cpu(p))
+#define cpu_curr(cpu)		(cpu_rq(cpu)->curr)
+#define raw_rq()		(&__raw_get_cpu_var(runqueues))
+
+#ifdef CONFIG_SMP
+
+#define rcu_dereference_check_sched_domain(p) \
+	rcu_dereference_check((p), \
+			      lockdep_is_held(&sched_domains_mutex))
+
+/*
+ * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
+ * See detach_destroy_domains: synchronize_sched for details.
+ *
+ * The domain tree of any CPU may only be accessed from within
+ * preempt-disabled sections.
+ */
+#define for_each_domain(cpu, __sd) \
+	for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
+			__sd; __sd = __sd->parent)
+
+#define for_each_lower_domain(sd) for (; sd; sd = sd->child)
+
+/**
+ * highest_flag_domain - Return highest sched_domain containing flag.
+ * @cpu:	The cpu whose highest level of sched domain is to
+ *		be returned.
+ * @flag:	The flag to check for the highest sched_domain
+ *		for the given cpu.
+ *
+ * Returns the highest sched_domain of a cpu which contains the given flag.
+ */
+static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
+{
+	struct sched_domain *sd, *hsd = NULL;
+
+	for_each_domain(cpu, sd) {
+		if (!(sd->flags & flag))
+			break;
+		hsd = sd;
+	}
+
+	return hsd;
+}
+
+DECLARE_PER_CPU(struct sched_domain *, sd_llc);
+DECLARE_PER_CPU(int, sd_llc_id);
+
+#endif /* CONFIG_SMP */
+
+#include "stats.h"
+#include "auto_group.h"
+
+#ifdef CONFIG_CGROUP_SCHED
+
+/*
+ * Return the group to which this tasks belongs.
+ *
+ * We use task_subsys_state_check() and extend the RCU verification with
+ * pi->lock and rq->lock because cpu_cgroup_attach() holds those locks for each
+ * task it moves into the cgroup. Therefore by holding either of those locks,
+ * we pin the task to the current cgroup.
+ */
+static inline struct task_group *task_group(struct task_struct *p)
+{
+	struct task_group *tg;
+	struct cgroup_subsys_state *css;
+
+	css = task_subsys_state_check(p, cpu_cgroup_subsys_id,
+			lockdep_is_held(&p->pi_lock) ||
+			lockdep_is_held(&task_rq(p)->lock));
+	tg = container_of(css, struct task_group, css);
+
+	return autogroup_task_group(p, tg);
+}
+
+/* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
+static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
+{
+#if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
+	struct task_group *tg = task_group(p);
+#endif
+
+#ifdef CONFIG_FAIR_GROUP_SCHED
+	p->se.cfs_rq = tg->cfs_rq[cpu];
+	p->se.parent = tg->se[cpu];
+#endif
+
+#ifdef CONFIG_RT_GROUP_SCHED
+	p->rt.rt_rq  = tg->rt_rq[cpu];
+	p->rt.parent = tg->rt_se[cpu];
+#endif
+}
+
+#else /* CONFIG_CGROUP_SCHED */
+
+static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
+static inline struct task_group *task_group(struct task_struct *p)
+{
+	return NULL;
+}
+
+#endif /* CONFIG_CGROUP_SCHED */
+
+static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
+{
+	set_task_rq(p, cpu);
+#ifdef CONFIG_SMP
+	/*
+	 * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
+	 * successfuly executed on another CPU. We must ensure that updates of
+	 * per-task data have been completed by this moment.
+	 */
+	smp_wmb();
+	task_thread_info(p)->cpu = cpu;
+#endif
+}
+
+/*
+ * Tunables that become constants when CONFIG_SCHED_DEBUG is off:
+ */
+#ifdef CONFIG_SCHED_DEBUG
+# include <linux/jump_label.h>
+# define const_debug __read_mostly
+#else
+# define const_debug const
+#endif
+
+extern const_debug unsigned int sysctl_sched_features;
+
+#define SCHED_FEAT(name, enabled)	\
+	__SCHED_FEAT_##name ,
+
+enum {
+#include "features.h"
+	__SCHED_FEAT_NR,
+};
+
+#undef SCHED_FEAT
+
+#if defined(CONFIG_SCHED_DEBUG) && defined(HAVE_JUMP_LABEL)
+static __always_inline bool static_branch__true(struct jump_label_key *key)
+{
+	return likely(static_branch(key)); /* Not out of line branch. */
+}
+
+static __always_inline bool static_branch__false(struct jump_label_key *key)
+{
+	return unlikely(static_branch(key)); /* Out of line branch. */
+}
+
+#define SCHED_FEAT(name, enabled)					\
+static __always_inline bool static_branch_##name(struct jump_label_key *key) \
+{									\
+	return static_branch__##enabled(key);				\
+}
+
+#include "features.h"
+
+#undef SCHED_FEAT
+
+extern struct jump_label_key sched_feat_keys[__SCHED_FEAT_NR];
+#define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
+#else /* !(SCHED_DEBUG && HAVE_JUMP_LABEL) */
+#define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
+#endif /* SCHED_DEBUG && HAVE_JUMP_LABEL */
+
+static inline u64 global_rt_period(void)
+{
+	return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
+}
+
+static inline u64 global_rt_runtime(void)
+{
+	if (sysctl_sched_rt_runtime < 0)
+		return RUNTIME_INF;
+
+	return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
+}
+
+
+
+static inline int task_current(struct rq *rq, struct task_struct *p)
+{
+	return rq->curr == p;
+}
+
+static inline int task_running(struct rq *rq, struct task_struct *p)
+{
+#ifdef CONFIG_SMP
+	return p->on_cpu;
+#else
+	return task_current(rq, p);
+#endif
+}
+
+
+#ifndef prepare_arch_switch
+# define prepare_arch_switch(next)	do { } while (0)
+#endif
+#ifndef finish_arch_switch
+# define finish_arch_switch(prev)	do { } while (0)
+#endif
+
+#ifndef __ARCH_WANT_UNLOCKED_CTXSW
+static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next)
+{
+#ifdef CONFIG_SMP
+	/*
+	 * We can optimise this out completely for !SMP, because the
+	 * SMP rebalancing from interrupt is the only thing that cares
+	 * here.
+	 */
+	next->on_cpu = 1;
+#endif
+}
+
+static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
+{
+#ifdef CONFIG_SMP
+	/*
+	 * After ->on_cpu is cleared, the task can be moved to a different CPU.
+	 * We must ensure this doesn't happen until the switch is completely
+	 * finished.
+	 */
+	smp_wmb();
+	prev->on_cpu = 0;
+#endif
+#ifdef CONFIG_DEBUG_SPINLOCK
+	/* this is a valid case when another task releases the spinlock */
+	rq->lock.owner = current;
+#endif
+	/*
+	 * If we are tracking spinlock dependencies then we have to
+	 * fix up the runqueue lock - which gets 'carried over' from
+	 * prev into current:
+	 */
+	spin_acquire(&rq->lock.dep_map, 0, 0, _THIS_IP_);
+
+	raw_spin_unlock_irq(&rq->lock);
+}
+
+#else /* __ARCH_WANT_UNLOCKED_CTXSW */
+static inline void prepare_lock_switch(struct rq *rq, struct task_struct *next)
+{
+#ifdef CONFIG_SMP
+	/*
+	 * We can optimise this out completely for !SMP, because the
+	 * SMP rebalancing from interrupt is the only thing that cares
+	 * here.
+	 */
+	next->on_cpu = 1;
+#endif
+#ifdef __ARCH_WANT_INTERRUPTS_ON_CTXSW
+	raw_spin_unlock_irq(&rq->lock);
+#else
+	raw_spin_unlock(&rq->lock);
+#endif
+}
+
+static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
+{
+#ifdef CONFIG_SMP
+	/*
+	 * After ->on_cpu is cleared, the task can be moved to a different CPU.
+	 * We must ensure this doesn't happen until the switch is completely
+	 * finished.
+	 */
+	smp_wmb();
+	prev->on_cpu = 0;
+#endif
+#ifndef __ARCH_WANT_INTERRUPTS_ON_CTXSW
+	local_irq_enable();
+#endif
+}
+#endif /* __ARCH_WANT_UNLOCKED_CTXSW */
+
+
+static inline void update_load_add(struct load_weight *lw, unsigned long inc)
+{
+	lw->weight += inc;
+	lw->inv_weight = 0;
+}
+
+static inline void update_load_sub(struct load_weight *lw, unsigned long dec)
+{
+	lw->weight -= dec;
+	lw->inv_weight = 0;
+}
+
+static inline void update_load_set(struct load_weight *lw, unsigned long w)
+{
+	lw->weight = w;
+	lw->inv_weight = 0;
+}
+
+/*
+ * To aid in avoiding the subversion of "niceness" due to uneven distribution
+ * of tasks with abnormal "nice" values across CPUs the contribution that
+ * each task makes to its run queue's load is weighted according to its
+ * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
+ * scaled version of the new time slice allocation that they receive on time
+ * slice expiry etc.
+ */
+
+#define WEIGHT_IDLEPRIO                3
+#define WMULT_IDLEPRIO         1431655765
+
+/*
+ * Nice levels are multiplicative, with a gentle 10% change for every
+ * nice level changed. I.e. when a CPU-bound task goes from nice 0 to
+ * nice 1, it will get ~10% less CPU time than another CPU-bound task
+ * that remained on nice 0.
+ *
+ * The "10% effect" is relative and cumulative: from _any_ nice level,
+ * if you go up 1 level, it's -10% CPU usage, if you go down 1 level
+ * it's +10% CPU usage. (to achieve that we use a multiplier of 1.25.
+ * If a task goes up by ~10% and another task goes down by ~10% then
+ * the relative distance between them is ~25%.)
+ */
+static const int prio_to_weight[40] = {
+ /* -20 */     88761,     71755,     56483,     46273,     36291,
+ /* -15 */     29154,     23254,     18705,     14949,     11916,
+ /* -10 */      9548,      7620,      6100,      4904,      3906,
+ /*  -5 */      3121,      2501,      1991,      1586,      1277,
+ /*   0 */      1024,       820,       655,       526,       423,
+ /*   5 */       335,       272,       215,       172,       137,
+ /*  10 */       110,        87,        70,        56,        45,
+ /*  15 */        36,        29,        23,        18,        15,
+};
+
+/*
+ * Inverse (2^32/x) values of the prio_to_weight[] array, precalculated.
+ *
+ * In cases where the weight does not change often, we can use the
+ * precalculated inverse to speed up arithmetics by turning divisions
+ * into multiplications:
+ */
+static const u32 prio_to_wmult[40] = {
+ /* -20 */     48388,     59856,     76040,     92818,    118348,
+ /* -15 */    147320,    184698,    229616,    287308,    360437,
+ /* -10 */    449829,    563644,    704093,    875809,   1099582,
+ /*  -5 */   1376151,   1717300,   2157191,   2708050,   3363326,
+ /*   0 */   4194304,   5237765,   6557202,   8165337,  10153587,
+ /*   5 */  12820798,  15790321,  19976592,  24970740,  31350126,
+ /*  10 */  39045157,  49367440,  61356676,  76695844,  95443717,
+ /*  15 */ 119304647, 148102320, 186737708, 238609294, 286331153,
+};
+
+/* Time spent by the tasks of the cpu accounting group executing in ... */
+enum cpuacct_stat_index {
+	CPUACCT_STAT_USER,	/* ... user mode */
+	CPUACCT_STAT_SYSTEM,	/* ... kernel mode */
+
+	CPUACCT_STAT_NSTATS,
+};
+
+
+#define sched_class_highest (&stop_sched_class)
+#define for_each_class(class) \
+   for (class = sched_class_highest; class; class = class->next)
+
+extern const struct sched_class stop_sched_class;
+extern const struct sched_class rt_sched_class;
+extern const struct sched_class fair_sched_class;
+extern const struct sched_class idle_sched_class;
+
+
+#ifdef CONFIG_SMP
+
+extern void trigger_load_balance(struct rq *rq, int cpu);
+extern void idle_balance(int this_cpu, struct rq *this_rq);
+
+#else	/* CONFIG_SMP */
+
+static inline void idle_balance(int cpu, struct rq *rq)
+{
+}
+
+#endif
+
+extern void sysrq_sched_debug_show(void);
+extern void sched_init_granularity(void);
+extern void update_max_interval(void);
+extern void update_group_power(struct sched_domain *sd, int cpu);
+extern int update_runtime(struct notifier_block *nfb, unsigned long action, void *hcpu);
+extern void init_sched_rt_class(void);
+extern void init_sched_fair_class(void);
+
+extern void resched_task(struct task_struct *p);
+extern void resched_cpu(int cpu);
+
+extern struct rt_bandwidth def_rt_bandwidth;
+extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
+
+extern void update_cpu_load(struct rq *this_rq);
+
+#ifdef CONFIG_CGROUP_CPUACCT
+#include <linux/cgroup.h>
+/* track cpu usage of a group of tasks and its child groups */
+struct cpuacct {
+	struct cgroup_subsys_state css;
+	/* cpuusage holds pointer to a u64-type object on every cpu */
+	u64 __percpu *cpuusage;
+	struct kernel_cpustat __percpu *cpustat;
+};
+
+/* return cpu accounting group corresponding to this container */
+static inline struct cpuacct *cgroup_ca(struct cgroup *cgrp)
+{
+	return container_of(cgroup_subsys_state(cgrp, cpuacct_subsys_id),
+			    struct cpuacct, css);
+}
+
+/* return cpu accounting group to which this task belongs */
+static inline struct cpuacct *task_ca(struct task_struct *tsk)
+{
+	return container_of(task_subsys_state(tsk, cpuacct_subsys_id),
+			    struct cpuacct, css);
+}
+
+static inline struct cpuacct *parent_ca(struct cpuacct *ca)
+{
+	if (!ca || !ca->css.cgroup->parent)
+		return NULL;
+	return cgroup_ca(ca->css.cgroup->parent);
+}
+
+extern void cpuacct_charge(struct task_struct *tsk, u64 cputime);
+#else
+static inline void cpuacct_charge(struct task_struct *tsk, u64 cputime) {}
+#endif
+
+static inline void inc_nr_running(struct rq *rq)
+{
+	rq->nr_running++;
+}
+
+static inline void dec_nr_running(struct rq *rq)
+{
+	rq->nr_running--;
+}
+
+extern void update_rq_clock(struct rq *rq);
+
+extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
+extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
+
+extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags);
+
+extern const_debug unsigned int sysctl_sched_time_avg;
+extern const_debug unsigned int sysctl_sched_nr_migrate;
+extern const_debug unsigned int sysctl_sched_migration_cost;
+
+static inline u64 sched_avg_period(void)
+{
+	return (u64)sysctl_sched_time_avg * NSEC_PER_MSEC / 2;
+}
+
+void calc_load_account_idle(struct rq *this_rq);
+
+#ifdef CONFIG_SCHED_HRTICK
+
+/*
+ * Use hrtick when:
+ *  - enabled by features
+ *  - hrtimer is actually high res
+ */
+static inline int hrtick_enabled(struct rq *rq)
+{
+	if (!sched_feat(HRTICK))
+		return 0;
+	if (!cpu_active(cpu_of(rq)))
+		return 0;
+	return hrtimer_is_hres_active(&rq->hrtick_timer);
+}
+
+void hrtick_start(struct rq *rq, u64 delay);
+
+#else
+
+static inline int hrtick_enabled(struct rq *rq)
+{
+	return 0;
+}
+
+#endif /* CONFIG_SCHED_HRTICK */
+
+#ifdef CONFIG_SMP
+extern void sched_avg_update(struct rq *rq);
+static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta)
+{
+	rq->rt_avg += rt_delta;
+	sched_avg_update(rq);
+}
+#else
+static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta) { }
+static inline void sched_avg_update(struct rq *rq) { }
+#endif
+
+extern void start_bandwidth_timer(struct hrtimer *period_timer, ktime_t period);
+
+#ifdef CONFIG_SMP
+#ifdef CONFIG_PREEMPT
+
+static inline void double_rq_lock(struct rq *rq1, struct rq *rq2);
+
+/*
+ * fair double_lock_balance: Safely acquires both rq->locks in a fair
+ * way at the expense of forcing extra atomic operations in all
+ * invocations.  This assures that the double_lock is acquired using the
+ * same underlying policy as the spinlock_t on this architecture, which
+ * reduces latency compared to the unfair variant below.  However, it
+ * also adds more overhead and therefore may reduce throughput.
+ */
+static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
+	__releases(this_rq->lock)
+	__acquires(busiest->lock)
+	__acquires(this_rq->lock)
+{
+	raw_spin_unlock(&this_rq->lock);
+	double_rq_lock(this_rq, busiest);
+
+	return 1;
+}
+
+#else
+/*
+ * Unfair double_lock_balance: Optimizes throughput at the expense of
+ * latency by eliminating extra atomic operations when the locks are
+ * already in proper order on entry.  This favors lower cpu-ids and will
+ * grant the double lock to lower cpus over higher ids under contention,
+ * regardless of entry order into the function.
+ */
+static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
+	__releases(this_rq->lock)
+	__acquires(busiest->lock)
+	__acquires(this_rq->lock)
+{
+	int ret = 0;
+
+	if (unlikely(!raw_spin_trylock(&busiest->lock))) {
+		if (busiest < this_rq) {
+			raw_spin_unlock(&this_rq->lock);
+			raw_spin_lock(&busiest->lock);
+			raw_spin_lock_nested(&this_rq->lock,
+					      SINGLE_DEPTH_NESTING);
+			ret = 1;
+		} else
+			raw_spin_lock_nested(&busiest->lock,
+					      SINGLE_DEPTH_NESTING);
+	}
+	return ret;
+}
+
+#endif /* CONFIG_PREEMPT */
+
+/*
+ * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
+ */
+static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
+{
+	if (unlikely(!irqs_disabled())) {
+		/* printk() doesn't work good under rq->lock */
+		raw_spin_unlock(&this_rq->lock);
+		BUG_ON(1);
+	}
+
+	return _double_lock_balance(this_rq, busiest);
+}
+
+static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
+	__releases(busiest->lock)
+{
+	raw_spin_unlock(&busiest->lock);
+	lock_set_subclass(&this_rq->lock.dep_map, 0, _RET_IP_);
+}
+
+/*
+ * double_rq_lock - safely lock two runqueues
+ *
+ * Note this does not disable interrupts like task_rq_lock,
+ * you need to do so manually before calling.
+ */
+static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
+	__acquires(rq1->lock)
+	__acquires(rq2->lock)
+{
+	BUG_ON(!irqs_disabled());
+	if (rq1 == rq2) {
+		raw_spin_lock(&rq1->lock);
+		__acquire(rq2->lock);	/* Fake it out ;) */
+	} else {
+		if (rq1 < rq2) {
+			raw_spin_lock(&rq1->lock);
+			raw_spin_lock_nested(&rq2->lock, SINGLE_DEPTH_NESTING);
+		} else {
+			raw_spin_lock(&rq2->lock);
+			raw_spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING);
+		}
+	}
+}
+
+/*
+ * double_rq_unlock - safely unlock two runqueues
+ *
+ * Note this does not restore interrupts like task_rq_unlock,
+ * you need to do so manually after calling.
+ */
+static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
+	__releases(rq1->lock)
+	__releases(rq2->lock)
+{
+	raw_spin_unlock(&rq1->lock);
+	if (rq1 != rq2)
+		raw_spin_unlock(&rq2->lock);
+	else
+		__release(rq2->lock);
+}
+
+#else /* CONFIG_SMP */
+
+/*
+ * double_rq_lock - safely lock two runqueues
+ *
+ * Note this does not disable interrupts like task_rq_lock,
+ * you need to do so manually before calling.
+ */
+static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
+	__acquires(rq1->lock)
+	__acquires(rq2->lock)
+{
+	BUG_ON(!irqs_disabled());
+	BUG_ON(rq1 != rq2);
+	raw_spin_lock(&rq1->lock);
+	__acquire(rq2->lock);	/* Fake it out ;) */
+}
+
+/*
+ * double_rq_unlock - safely unlock two runqueues
+ *
+ * Note this does not restore interrupts like task_rq_unlock,
+ * you need to do so manually after calling.
+ */
+static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
+	__releases(rq1->lock)
+	__releases(rq2->lock)
+{
+	BUG_ON(rq1 != rq2);
+	raw_spin_unlock(&rq1->lock);
+	__release(rq2->lock);
+}
+
+#endif
+
+extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
+extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
+extern void print_cfs_stats(struct seq_file *m, int cpu);
+extern void print_rt_stats(struct seq_file *m, int cpu);
+
+extern void init_cfs_rq(struct cfs_rq *cfs_rq);
+extern void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq);
+extern void unthrottle_offline_cfs_rqs(struct rq *rq);
+
+extern void account_cfs_bandwidth_used(int enabled, int was_enabled);
+
+#ifdef CONFIG_NO_HZ
+enum rq_nohz_flag_bits {
+	NOHZ_TICK_STOPPED,
+	NOHZ_BALANCE_KICK,
+	NOHZ_IDLE,
+};
+
+#define nohz_flags(cpu)	(&cpu_rq(cpu)->nohz_flags)
+#endif
diff --git a/kernel/sched/stats.c b/kernel/sched/stats.c
new file mode 100644
index 00000000000..2a581ba8e19
--- /dev/null
+++ b/kernel/sched/stats.c
@@ -0,0 +1,111 @@
+
+#include <linux/slab.h>
+#include <linux/fs.h>
+#include <linux/seq_file.h>
+#include <linux/proc_fs.h>
+
+#include "sched.h"
+
+/*
+ * bump this up when changing the output format or the meaning of an existing
+ * format, so that tools can adapt (or abort)
+ */
+#define SCHEDSTAT_VERSION 15
+
+static int show_schedstat(struct seq_file *seq, void *v)
+{
+	int cpu;
+	int mask_len = DIV_ROUND_UP(NR_CPUS, 32) * 9;
+	char *mask_str = kmalloc(mask_len, GFP_KERNEL);
+
+	if (mask_str == NULL)
+		return -ENOMEM;
+
+	seq_printf(seq, "version %d\n", SCHEDSTAT_VERSION);
+	seq_printf(seq, "timestamp %lu\n", jiffies);
+	for_each_online_cpu(cpu) {
+		struct rq *rq = cpu_rq(cpu);
+#ifdef CONFIG_SMP
+		struct sched_domain *sd;
+		int dcount = 0;
+#endif
+
+		/* runqueue-specific stats */
+		seq_printf(seq,
+		    "cpu%d %u %u %u %u %u %u %llu %llu %lu",
+		    cpu, rq->yld_count,
+		    rq->sched_switch, rq->sched_count, rq->sched_goidle,
+		    rq->ttwu_count, rq->ttwu_local,
+		    rq->rq_cpu_time,
+		    rq->rq_sched_info.run_delay, rq->rq_sched_info.pcount);
+
+		seq_printf(seq, "\n");
+
+#ifdef CONFIG_SMP
+		/* domain-specific stats */
+		rcu_read_lock();
+		for_each_domain(cpu, sd) {
+			enum cpu_idle_type itype;
+
+			cpumask_scnprintf(mask_str, mask_len,
+					  sched_domain_span(sd));
+			seq_printf(seq, "domain%d %s", dcount++, mask_str);
+			for (itype = CPU_IDLE; itype < CPU_MAX_IDLE_TYPES;
+					itype++) {
+				seq_printf(seq, " %u %u %u %u %u %u %u %u",
+				    sd->lb_count[itype],
+				    sd->lb_balanced[itype],
+				    sd->lb_failed[itype],
+				    sd->lb_imbalance[itype],
+				    sd->lb_gained[itype],
+				    sd->lb_hot_gained[itype],
+				    sd->lb_nobusyq[itype],
+				    sd->lb_nobusyg[itype]);
+			}
+			seq_printf(seq,
+				   " %u %u %u %u %u %u %u %u %u %u %u %u\n",
+			    sd->alb_count, sd->alb_failed, sd->alb_pushed,
+			    sd->sbe_count, sd->sbe_balanced, sd->sbe_pushed,
+			    sd->sbf_count, sd->sbf_balanced, sd->sbf_pushed,
+			    sd->ttwu_wake_remote, sd->ttwu_move_affine,
+			    sd->ttwu_move_balance);
+		}
+		rcu_read_unlock();
+#endif
+	}
+	kfree(mask_str);
+	return 0;
+}
+
+static int schedstat_open(struct inode *inode, struct file *file)
+{
+	unsigned int size = PAGE_SIZE * (1 + num_online_cpus() / 32);
+	char *buf = kmalloc(size, GFP_KERNEL);
+	struct seq_file *m;
+	int res;
+
+	if (!buf)
+		return -ENOMEM;
+	res = single_open(file, show_schedstat, NULL);
+	if (!res) {
+		m = file->private_data;
+		m->buf = buf;
+		m->size = size;
+	} else
+		kfree(buf);
+	return res;
+}
+
+static const struct file_operations proc_schedstat_operations = {
+	.open    = schedstat_open,
+	.read    = seq_read,
+	.llseek  = seq_lseek,
+	.release = single_release,
+};
+
+static int __init proc_schedstat_init(void)
+{
+	proc_create("schedstat", 0, NULL, &proc_schedstat_operations);
+	return 0;
+}
+module_init(proc_schedstat_init);
diff --git a/kernel/sched/stats.h b/kernel/sched/stats.h
new file mode 100644
index 00000000000..2ef90a51ec5
--- /dev/null
+++ b/kernel/sched/stats.h
@@ -0,0 +1,231 @@
+
+#ifdef CONFIG_SCHEDSTATS
+
+/*
+ * Expects runqueue lock to be held for atomicity of update
+ */
+static inline void
+rq_sched_info_arrive(struct rq *rq, unsigned long long delta)
+{
+	if (rq) {
+		rq->rq_sched_info.run_delay += delta;
+		rq->rq_sched_info.pcount++;
+	}
+}
+
+/*
+ * Expects runqueue lock to be held for atomicity of update
+ */
+static inline void
+rq_sched_info_depart(struct rq *rq, unsigned long long delta)
+{
+	if (rq)
+		rq->rq_cpu_time += delta;
+}
+
+static inline void
+rq_sched_info_dequeued(struct rq *rq, unsigned long long delta)
+{
+	if (rq)
+		rq->rq_sched_info.run_delay += delta;
+}
+# define schedstat_inc(rq, field)	do { (rq)->field++; } while (0)
+# define schedstat_add(rq, field, amt)	do { (rq)->field += (amt); } while (0)
+# define schedstat_set(var, val)	do { var = (val); } while (0)
+#else /* !CONFIG_SCHEDSTATS */
+static inline void
+rq_sched_info_arrive(struct rq *rq, unsigned long long delta)
+{}
+static inline void
+rq_sched_info_dequeued(struct rq *rq, unsigned long long delta)
+{}
+static inline void
+rq_sched_info_depart(struct rq *rq, unsigned long long delta)
+{}
+# define schedstat_inc(rq, field)	do { } while (0)
+# define schedstat_add(rq, field, amt)	do { } while (0)
+# define schedstat_set(var, val)	do { } while (0)
+#endif
+
+#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_TASK_DELAY_ACCT)
+static inline void sched_info_reset_dequeued(struct task_struct *t)
+{
+	t->sched_info.last_queued = 0;
+}
+
+/*
+ * We are interested in knowing how long it was from the *first* time a
+ * task was queued to the time that it finally hit a cpu, we call this routine
+ * from dequeue_task() to account for possible rq->clock skew across cpus. The
+ * delta taken on each cpu would annul the skew.
+ */
+static inline void sched_info_dequeued(struct task_struct *t)
+{
+	unsigned long long now = task_rq(t)->clock, delta = 0;
+
+	if (unlikely(sched_info_on()))
+		if (t->sched_info.last_queued)
+			delta = now - t->sched_info.last_queued;
+	sched_info_reset_dequeued(t);
+	t->sched_info.run_delay += delta;
+
+	rq_sched_info_dequeued(task_rq(t), delta);
+}
+
+/*
+ * Called when a task finally hits the cpu.  We can now calculate how
+ * long it was waiting to run.  We also note when it began so that we
+ * can keep stats on how long its timeslice is.
+ */
+static void sched_info_arrive(struct task_struct *t)
+{
+	unsigned long long now = task_rq(t)->clock, delta = 0;
+
+	if (t->sched_info.last_queued)
+		delta = now - t->sched_info.last_queued;
+	sched_info_reset_dequeued(t);
+	t->sched_info.run_delay += delta;
+	t->sched_info.last_arrival = now;
+	t->sched_info.pcount++;
+
+	rq_sched_info_arrive(task_rq(t), delta);
+}
+
+/*
+ * This function is only called from enqueue_task(), but also only updates
+ * the timestamp if it is already not set.  It's assumed that
+ * sched_info_dequeued() will clear that stamp when appropriate.
+ */
+static inline void sched_info_queued(struct task_struct *t)
+{
+	if (unlikely(sched_info_on()))
+		if (!t->sched_info.last_queued)
+			t->sched_info.last_queued = task_rq(t)->clock;
+}
+
+/*
+ * Called when a process ceases being the active-running process, either
+ * voluntarily or involuntarily.  Now we can calculate how long we ran.
+ * Also, if the process is still in the TASK_RUNNING state, call
+ * sched_info_queued() to mark that it has now again started waiting on
+ * the runqueue.
+ */
+static inline void sched_info_depart(struct task_struct *t)
+{
+	unsigned long long delta = task_rq(t)->clock -
+					t->sched_info.last_arrival;
+
+	rq_sched_info_depart(task_rq(t), delta);
+
+	if (t->state == TASK_RUNNING)
+		sched_info_queued(t);
+}
+
+/*
+ * Called when tasks are switched involuntarily due, typically, to expiring
+ * their time slice.  (This may also be called when switching to or from
+ * the idle task.)  We are only called when prev != next.
+ */
+static inline void
+__sched_info_switch(struct task_struct *prev, struct task_struct *next)
+{
+	struct rq *rq = task_rq(prev);
+
+	/*
+	 * prev now departs the cpu.  It's not interesting to record
+	 * stats about how efficient we were at scheduling the idle
+	 * process, however.
+	 */
+	if (prev != rq->idle)
+		sched_info_depart(prev);
+
+	if (next != rq->idle)
+		sched_info_arrive(next);
+}
+static inline void
+sched_info_switch(struct task_struct *prev, struct task_struct *next)
+{
+	if (unlikely(sched_info_on()))
+		__sched_info_switch(prev, next);
+}
+#else
+#define sched_info_queued(t)			do { } while (0)
+#define sched_info_reset_dequeued(t)	do { } while (0)
+#define sched_info_dequeued(t)			do { } while (0)
+#define sched_info_switch(t, next)		do { } while (0)
+#endif /* CONFIG_SCHEDSTATS || CONFIG_TASK_DELAY_ACCT */
+
+/*
+ * The following are functions that support scheduler-internal time accounting.
+ * These functions are generally called at the timer tick.  None of this depends
+ * on CONFIG_SCHEDSTATS.
+ */
+
+/**
+ * account_group_user_time - Maintain utime for a thread group.
+ *
+ * @tsk:	Pointer to task structure.
+ * @cputime:	Time value by which to increment the utime field of the
+ *		thread_group_cputime structure.
+ *
+ * If thread group time is being maintained, get the structure for the
+ * running CPU and update the utime field there.
+ */
+static inline void account_group_user_time(struct task_struct *tsk,
+					   cputime_t cputime)
+{
+	struct thread_group_cputimer *cputimer = &tsk->signal->cputimer;
+
+	if (!cputimer->running)
+		return;
+
+	raw_spin_lock(&cputimer->lock);
+	cputimer->cputime.utime += cputime;
+	raw_spin_unlock(&cputimer->lock);
+}
+
+/**
+ * account_group_system_time - Maintain stime for a thread group.
+ *
+ * @tsk:	Pointer to task structure.
+ * @cputime:	Time value by which to increment the stime field of the
+ *		thread_group_cputime structure.
+ *
+ * If thread group time is being maintained, get the structure for the
+ * running CPU and update the stime field there.
+ */
+static inline void account_group_system_time(struct task_struct *tsk,
+					     cputime_t cputime)
+{
+	struct thread_group_cputimer *cputimer = &tsk->signal->cputimer;
+
+	if (!cputimer->running)
+		return;
+
+	raw_spin_lock(&cputimer->lock);
+	cputimer->cputime.stime += cputime;
+	raw_spin_unlock(&cputimer->lock);
+}
+
+/**
+ * account_group_exec_runtime - Maintain exec runtime for a thread group.
+ *
+ * @tsk:	Pointer to task structure.
+ * @ns:		Time value by which to increment the sum_exec_runtime field
+ *		of the thread_group_cputime structure.
+ *
+ * If thread group time is being maintained, get the structure for the
+ * running CPU and update the sum_exec_runtime field there.
+ */
+static inline void account_group_exec_runtime(struct task_struct *tsk,
+					      unsigned long long ns)
+{
+	struct thread_group_cputimer *cputimer = &tsk->signal->cputimer;
+
+	if (!cputimer->running)
+		return;
+
+	raw_spin_lock(&cputimer->lock);
+	cputimer->cputime.sum_exec_runtime += ns;
+	raw_spin_unlock(&cputimer->lock);
+}
diff --git a/kernel/sched/stop_task.c b/kernel/sched/stop_task.c
new file mode 100644
index 00000000000..7b386e86fd2
--- /dev/null
+++ b/kernel/sched/stop_task.c
@@ -0,0 +1,108 @@
+#include "sched.h"
+
+/*
+ * stop-task scheduling class.
+ *
+ * The stop task is the highest priority task in the system, it preempts
+ * everything and will be preempted by nothing.
+ *
+ * See kernel/stop_machine.c
+ */
+
+#ifdef CONFIG_SMP
+static int
+select_task_rq_stop(struct task_struct *p, int sd_flag, int flags)
+{
+	return task_cpu(p); /* stop tasks as never migrate */
+}
+#endif /* CONFIG_SMP */
+
+static void
+check_preempt_curr_stop(struct rq *rq, struct task_struct *p, int flags)
+{
+	/* we're never preempted */
+}
+
+static struct task_struct *pick_next_task_stop(struct rq *rq)
+{
+	struct task_struct *stop = rq->stop;
+
+	if (stop && stop->on_rq)
+		return stop;
+
+	return NULL;
+}
+
+static void
+enqueue_task_stop(struct rq *rq, struct task_struct *p, int flags)
+{
+	inc_nr_running(rq);
+}
+
+static void
+dequeue_task_stop(struct rq *rq, struct task_struct *p, int flags)
+{
+	dec_nr_running(rq);
+}
+
+static void yield_task_stop(struct rq *rq)
+{
+	BUG(); /* the stop task should never yield, its pointless. */
+}
+
+static void put_prev_task_stop(struct rq *rq, struct task_struct *prev)
+{
+}
+
+static void task_tick_stop(struct rq *rq, struct task_struct *curr, int queued)
+{
+}
+
+static void set_curr_task_stop(struct rq *rq)
+{
+}
+
+static void switched_to_stop(struct rq *rq, struct task_struct *p)
+{
+	BUG(); /* its impossible to change to this class */
+}
+
+static void
+prio_changed_stop(struct rq *rq, struct task_struct *p, int oldprio)
+{
+	BUG(); /* how!?, what priority? */
+}
+
+static unsigned int
+get_rr_interval_stop(struct rq *rq, struct task_struct *task)
+{
+	return 0;
+}
+
+/*
+ * Simple, special scheduling class for the per-CPU stop tasks:
+ */
+const struct sched_class stop_sched_class = {
+	.next			= &rt_sched_class,
+
+	.enqueue_task		= enqueue_task_stop,
+	.dequeue_task		= dequeue_task_stop,
+	.yield_task		= yield_task_stop,
+
+	.check_preempt_curr	= check_preempt_curr_stop,
+
+	.pick_next_task		= pick_next_task_stop,
+	.put_prev_task		= put_prev_task_stop,
+
+#ifdef CONFIG_SMP
+	.select_task_rq		= select_task_rq_stop,
+#endif
+
+	.set_curr_task          = set_curr_task_stop,
+	.task_tick		= task_tick_stop,
+
+	.get_rr_interval	= get_rr_interval_stop,
+
+	.prio_changed		= prio_changed_stop,
+	.switched_to		= switched_to_stop,
+};