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Diffstat (limited to 'kernel/time/ntp.c')
-rw-r--r--kernel/time/ntp.c85
1 files changed, 64 insertions, 21 deletions
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index f6117a4c7cb..6e039b144da 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -22,13 +22,16 @@
* NTP timekeeping variables:
*/
+DEFINE_SPINLOCK(ntp_lock);
+
+
/* USER_HZ period (usecs): */
unsigned long tick_usec = TICK_USEC;
/* ACTHZ period (nsecs): */
unsigned long tick_nsec;
-u64 tick_length;
+static u64 tick_length;
static u64 tick_length_base;
static struct hrtimer leap_timer;
@@ -49,7 +52,7 @@ static struct hrtimer leap_timer;
static int time_state = TIME_OK;
/* clock status bits: */
-int time_status = STA_UNSYNC;
+static int time_status = STA_UNSYNC;
/* TAI offset (secs): */
static long time_tai;
@@ -133,7 +136,7 @@ static inline void pps_reset_freq_interval(void)
/**
* pps_clear - Clears the PPS state variables
*
- * Must be called while holding a write on the xtime_lock
+ * Must be called while holding a write on the ntp_lock
*/
static inline void pps_clear(void)
{
@@ -149,7 +152,7 @@ static inline void pps_clear(void)
* the last PPS signal. When it reaches 0, indicate that PPS signal is
* missing.
*
- * Must be called while holding a write on the xtime_lock
+ * Must be called while holding a write on the ntp_lock
*/
static inline void pps_dec_valid(void)
{
@@ -233,6 +236,17 @@ static inline void pps_fill_timex(struct timex *txc)
#endif /* CONFIG_NTP_PPS */
+
+/**
+ * ntp_synced - Returns 1 if the NTP status is not UNSYNC
+ *
+ */
+static inline int ntp_synced(void)
+{
+ return !(time_status & STA_UNSYNC);
+}
+
+
/*
* NTP methods:
*/
@@ -275,7 +289,7 @@ static inline s64 ntp_update_offset_fll(s64 offset64, long secs)
time_status |= STA_MODE;
- return div_s64(offset64 << (NTP_SCALE_SHIFT - SHIFT_FLL), secs);
+ return div64_long(offset64 << (NTP_SCALE_SHIFT - SHIFT_FLL), secs);
}
static void ntp_update_offset(long offset)
@@ -330,11 +344,13 @@ static void ntp_update_offset(long offset)
/**
* ntp_clear - Clears the NTP state variables
- *
- * Must be called while holding a write on the xtime_lock
*/
void ntp_clear(void)
{
+ unsigned long flags;
+
+ spin_lock_irqsave(&ntp_lock, flags);
+
time_adjust = 0; /* stop active adjtime() */
time_status |= STA_UNSYNC;
time_maxerror = NTP_PHASE_LIMIT;
@@ -347,8 +363,23 @@ void ntp_clear(void)
/* Clear PPS state variables */
pps_clear();
+ spin_unlock_irqrestore(&ntp_lock, flags);
+
}
+
+u64 ntp_tick_length(void)
+{
+ unsigned long flags;
+ s64 ret;
+
+ spin_lock_irqsave(&ntp_lock, flags);
+ ret = tick_length;
+ spin_unlock_irqrestore(&ntp_lock, flags);
+ return ret;
+}
+
+
/*
* Leap second processing. If in leap-insert state at the end of the
* day, the system clock is set back one second; if in leap-delete
@@ -357,14 +388,15 @@ void ntp_clear(void)
static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer)
{
enum hrtimer_restart res = HRTIMER_NORESTART;
+ unsigned long flags;
+ int leap = 0;
- write_seqlock(&xtime_lock);
-
+ spin_lock_irqsave(&ntp_lock, flags);
switch (time_state) {
case TIME_OK:
break;
case TIME_INS:
- timekeeping_leap_insert(-1);
+ leap = -1;
time_state = TIME_OOP;
printk(KERN_NOTICE
"Clock: inserting leap second 23:59:60 UTC\n");
@@ -372,7 +404,7 @@ static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer)
res = HRTIMER_RESTART;
break;
case TIME_DEL:
- timekeeping_leap_insert(1);
+ leap = 1;
time_tai--;
time_state = TIME_WAIT;
printk(KERN_NOTICE
@@ -387,8 +419,14 @@ static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer)
time_state = TIME_OK;
break;
}
+ spin_unlock_irqrestore(&ntp_lock, flags);
- write_sequnlock(&xtime_lock);
+ /*
+ * We have to call this outside of the ntp_lock to keep
+ * the proper locking hierarchy
+ */
+ if (leap)
+ timekeeping_leap_insert(leap);
return res;
}
@@ -404,6 +442,9 @@ static enum hrtimer_restart ntp_leap_second(struct hrtimer *timer)
void second_overflow(void)
{
s64 delta;
+ unsigned long flags;
+
+ spin_lock_irqsave(&ntp_lock, flags);
/* Bump the maxerror field */
time_maxerror += MAXFREQ / NSEC_PER_USEC;
@@ -423,23 +464,25 @@ void second_overflow(void)
pps_dec_valid();
if (!time_adjust)
- return;
+ goto out;
if (time_adjust > MAX_TICKADJ) {
time_adjust -= MAX_TICKADJ;
tick_length += MAX_TICKADJ_SCALED;
- return;
+ goto out;
}
if (time_adjust < -MAX_TICKADJ) {
time_adjust += MAX_TICKADJ;
tick_length -= MAX_TICKADJ_SCALED;
- return;
+ goto out;
}
tick_length += (s64)(time_adjust * NSEC_PER_USEC / NTP_INTERVAL_FREQ)
<< NTP_SCALE_SHIFT;
time_adjust = 0;
+out:
+ spin_unlock_irqrestore(&ntp_lock, flags);
}
#ifdef CONFIG_GENERIC_CMOS_UPDATE
@@ -663,7 +706,7 @@ int do_adjtimex(struct timex *txc)
getnstimeofday(&ts);
- write_seqlock_irq(&xtime_lock);
+ spin_lock_irq(&ntp_lock);
if (txc->modes & ADJ_ADJTIME) {
long save_adjust = time_adjust;
@@ -705,7 +748,7 @@ int do_adjtimex(struct timex *txc)
/* fill PPS status fields */
pps_fill_timex(txc);
- write_sequnlock_irq(&xtime_lock);
+ spin_unlock_irq(&ntp_lock);
txc->time.tv_sec = ts.tv_sec;
txc->time.tv_usec = ts.tv_nsec;
@@ -903,7 +946,7 @@ void hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts)
pts_norm = pps_normalize_ts(*phase_ts);
- write_seqlock_irqsave(&xtime_lock, flags);
+ spin_lock_irqsave(&ntp_lock, flags);
/* clear the error bits, they will be set again if needed */
time_status &= ~(STA_PPSJITTER | STA_PPSWANDER | STA_PPSERROR);
@@ -916,7 +959,7 @@ void hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts)
* just start the frequency interval */
if (unlikely(pps_fbase.tv_sec == 0)) {
pps_fbase = *raw_ts;
- write_sequnlock_irqrestore(&xtime_lock, flags);
+ spin_unlock_irqrestore(&ntp_lock, flags);
return;
}
@@ -931,7 +974,7 @@ void hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts)
time_status |= STA_PPSJITTER;
/* restart the frequency calibration interval */
pps_fbase = *raw_ts;
- write_sequnlock_irqrestore(&xtime_lock, flags);
+ spin_unlock_irqrestore(&ntp_lock, flags);
pr_err("hardpps: PPSJITTER: bad pulse\n");
return;
}
@@ -948,7 +991,7 @@ void hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts)
hardpps_update_phase(pts_norm.nsec);
- write_sequnlock_irqrestore(&xtime_lock, flags);
+ spin_unlock_irqrestore(&ntp_lock, flags);
}
EXPORT_SYMBOL(hardpps);
generated by cgit v1.2.3-70-g09d2 (git 2.51.2) at 2025-11-04 07:53:20 +0000