diff options
-rw-r--r-- | include/linux/timer.h | 6 | ||||
-rw-r--r-- | kernel/time/tick-sched.c | 16 | ||||
-rw-r--r-- | kernel/timer.c | 10 |
3 files changed, 30 insertions, 2 deletions
diff --git a/include/linux/timer.h b/include/linux/timer.h index e0c5c16c992f..c661710d3627 100644 --- a/include/linux/timer.h +++ b/include/linux/timer.h | |||
@@ -69,6 +69,12 @@ extern int __mod_timer(struct timer_list *timer, unsigned long expires); | |||
69 | extern int mod_timer(struct timer_list *timer, unsigned long expires); | 69 | extern int mod_timer(struct timer_list *timer, unsigned long expires); |
70 | 70 | ||
71 | /* | 71 | /* |
72 | * The jiffies value which is added to now, when there is no timer | ||
73 | * in the timer wheel: | ||
74 | */ | ||
75 | #define NEXT_TIMER_MAX_DELTA ((1UL << 30) - 1) | ||
76 | |||
77 | /* | ||
72 | * Return when the next timer-wheel timeout occurs (in absolute jiffies), | 78 | * Return when the next timer-wheel timeout occurs (in absolute jiffies), |
73 | * locks the timer base: | 79 | * locks the timer base: |
74 | */ | 80 | */ |
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index 3e7ebc4646b7..52db9e3c526e 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c | |||
@@ -247,6 +247,21 @@ void tick_nohz_stop_sched_tick(void) | |||
247 | if (cpu == tick_do_timer_cpu) | 247 | if (cpu == tick_do_timer_cpu) |
248 | tick_do_timer_cpu = -1; | 248 | tick_do_timer_cpu = -1; |
249 | 249 | ||
250 | ts->idle_sleeps++; | ||
251 | |||
252 | /* | ||
253 | * delta_jiffies >= NEXT_TIMER_MAX_DELTA signals that | ||
254 | * there is no timer pending or at least extremly far | ||
255 | * into the future (12 days for HZ=1000). In this case | ||
256 | * we simply stop the tick timer: | ||
257 | */ | ||
258 | if (unlikely(delta_jiffies >= NEXT_TIMER_MAX_DELTA)) { | ||
259 | ts->idle_expires.tv64 = KTIME_MAX; | ||
260 | if (ts->nohz_mode == NOHZ_MODE_HIGHRES) | ||
261 | hrtimer_cancel(&ts->sched_timer); | ||
262 | goto out; | ||
263 | } | ||
264 | |||
250 | /* | 265 | /* |
251 | * calculate the expiry time for the next timer wheel | 266 | * calculate the expiry time for the next timer wheel |
252 | * timer | 267 | * timer |
@@ -254,7 +269,6 @@ void tick_nohz_stop_sched_tick(void) | |||
254 | expires = ktime_add_ns(last_update, tick_period.tv64 * | 269 | expires = ktime_add_ns(last_update, tick_period.tv64 * |
255 | delta_jiffies); | 270 | delta_jiffies); |
256 | ts->idle_expires = expires; | 271 | ts->idle_expires = expires; |
257 | ts->idle_sleeps++; | ||
258 | 272 | ||
259 | if (ts->nohz_mode == NOHZ_MODE_HIGHRES) { | 273 | if (ts->nohz_mode == NOHZ_MODE_HIGHRES) { |
260 | hrtimer_start(&ts->sched_timer, expires, | 274 | hrtimer_start(&ts->sched_timer, expires, |
diff --git a/kernel/timer.c b/kernel/timer.c index 5ec5490f8d85..1a69705c2fb9 100644 --- a/kernel/timer.c +++ b/kernel/timer.c | |||
@@ -666,7 +666,7 @@ static inline void __run_timers(tvec_base_t *base) | |||
666 | static unsigned long __next_timer_interrupt(tvec_base_t *base) | 666 | static unsigned long __next_timer_interrupt(tvec_base_t *base) |
667 | { | 667 | { |
668 | unsigned long timer_jiffies = base->timer_jiffies; | 668 | unsigned long timer_jiffies = base->timer_jiffies; |
669 | unsigned long expires = timer_jiffies + (LONG_MAX >> 1); | 669 | unsigned long expires = timer_jiffies + NEXT_TIMER_MAX_DELTA; |
670 | int index, slot, array, found = 0; | 670 | int index, slot, array, found = 0; |
671 | struct timer_list *nte; | 671 | struct timer_list *nte; |
672 | tvec_t *varray[4]; | 672 | tvec_t *varray[4]; |
@@ -752,6 +752,14 @@ static unsigned long cmp_next_hrtimer_event(unsigned long now, | |||
752 | 752 | ||
753 | tsdelta = ktime_to_timespec(hr_delta); | 753 | tsdelta = ktime_to_timespec(hr_delta); |
754 | delta = timespec_to_jiffies(&tsdelta); | 754 | delta = timespec_to_jiffies(&tsdelta); |
755 | |||
756 | /* | ||
757 | * Limit the delta to the max value, which is checked in | ||
758 | * tick_nohz_stop_sched_tick(): | ||
759 | */ | ||
760 | if (delta > NEXT_TIMER_MAX_DELTA) | ||
761 | delta = NEXT_TIMER_MAX_DELTA; | ||
762 | |||
755 | /* | 763 | /* |
756 | * Take rounding errors in to account and make sure, that it | 764 | * Take rounding errors in to account and make sure, that it |
757 | * expires in the next tick. Otherwise we go into an endless | 765 | * expires in the next tick. Otherwise we go into an endless |