diff options
Diffstat (limited to 'arch/x86/kernel/cpu/perf_event.c')
| -rw-r--r-- | arch/x86/kernel/cpu/perf_event.c | 55 |
1 files changed, 45 insertions, 10 deletions
diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c index 60398a0d947..db5bdc8addf 100644 --- a/arch/x86/kernel/cpu/perf_event.c +++ b/arch/x86/kernel/cpu/perf_event.c @@ -21,6 +21,7 @@ #include <linux/kdebug.h> #include <linux/sched.h> #include <linux/uaccess.h> +#include <linux/slab.h> #include <linux/highmem.h> #include <linux/cpu.h> #include <linux/bitops.h> @@ -28,6 +29,7 @@ #include <asm/apic.h> #include <asm/stacktrace.h> #include <asm/nmi.h> +#include <asm/compat.h> static u64 perf_event_mask __read_mostly; @@ -158,7 +160,7 @@ struct x86_pmu { struct perf_event *event); struct event_constraint *event_constraints; - void (*cpu_prepare)(int cpu); + int (*cpu_prepare)(int cpu); void (*cpu_starting)(int cpu); void (*cpu_dying)(int cpu); void (*cpu_dead)(int cpu); @@ -1333,11 +1335,12 @@ static int __cpuinit x86_pmu_notifier(struct notifier_block *self, unsigned long action, void *hcpu) { unsigned int cpu = (long)hcpu; + int ret = NOTIFY_OK; switch (action & ~CPU_TASKS_FROZEN) { case CPU_UP_PREPARE: if (x86_pmu.cpu_prepare) - x86_pmu.cpu_prepare(cpu); + ret = x86_pmu.cpu_prepare(cpu); break; case CPU_STARTING: @@ -1350,6 +1353,7 @@ x86_pmu_notifier(struct notifier_block *self, unsigned long action, void *hcpu) x86_pmu.cpu_dying(cpu); break; + case CPU_UP_CANCELED: case CPU_DEAD: if (x86_pmu.cpu_dead) x86_pmu.cpu_dead(cpu); @@ -1359,7 +1363,7 @@ x86_pmu_notifier(struct notifier_block *self, unsigned long action, void *hcpu) break; } - return NOTIFY_OK; + return ret; } static void __init pmu_check_apic(void) @@ -1628,14 +1632,42 @@ copy_from_user_nmi(void *to, const void __user *from, unsigned long n) return len; } -static int copy_stack_frame(const void __user *fp, struct stack_frame *frame) +#ifdef CONFIG_COMPAT +static inline int +perf_callchain_user32(struct pt_regs *regs, struct perf_callchain_entry *entry) { - unsigned long bytes; + /* 32-bit process in 64-bit kernel. */ + struct stack_frame_ia32 frame; + const void __user *fp; - bytes = copy_from_user_nmi(frame, fp, sizeof(*frame)); + if (!test_thread_flag(TIF_IA32)) + return 0; + + fp = compat_ptr(regs->bp); + while (entry->nr < PERF_MAX_STACK_DEPTH) { + unsigned long bytes; + frame.next_frame = 0; + frame.return_address = 0; + + bytes = copy_from_user_nmi(&frame, fp, sizeof(frame)); + if (bytes != sizeof(frame)) + break; + + if (fp < compat_ptr(regs->sp)) + break; - return bytes == sizeof(*frame); + callchain_store(entry, frame.return_address); + fp = compat_ptr(frame.next_frame); + } + return 1; +} +#else +static inline int +perf_callchain_user32(struct pt_regs *regs, struct perf_callchain_entry *entry) +{ + return 0; } +#endif static void perf_callchain_user(struct pt_regs *regs, struct perf_callchain_entry *entry) @@ -1651,11 +1683,16 @@ perf_callchain_user(struct pt_regs *regs, struct perf_callchain_entry *entry) callchain_store(entry, PERF_CONTEXT_USER); callchain_store(entry, regs->ip); + if (perf_callchain_user32(regs, entry)) + return; + while (entry->nr < PERF_MAX_STACK_DEPTH) { + unsigned long bytes; frame.next_frame = NULL; frame.return_address = 0; - if (!copy_stack_frame(fp, &frame)) + bytes = copy_from_user_nmi(&frame, fp, sizeof(frame)); + if (bytes != sizeof(frame)) break; if ((unsigned long)fp < regs->sp) @@ -1702,7 +1739,6 @@ struct perf_callchain_entry *perf_callchain(struct pt_regs *regs) return entry; } -#ifdef CONFIG_EVENT_TRACING void perf_arch_fetch_caller_regs(struct pt_regs *regs, unsigned long ip, int skip) { regs->ip = ip; @@ -1714,4 +1750,3 @@ void perf_arch_fetch_caller_regs(struct pt_regs *regs, unsigned long ip, int ski regs->cs = __KERNEL_CS; local_save_flags(regs->flags); } -#endif |