diff options
| -rw-r--r-- | arch/arm/kernel/time.c | 10 | ||||
| -rw-r--r-- | include/linux/hrtimer.h | 4 | ||||
| -rw-r--r-- | kernel/hrtimer.c | 35 | ||||
| -rw-r--r-- | kernel/timer.c | 16 |
4 files changed, 61 insertions, 4 deletions
diff --git a/arch/arm/kernel/time.c b/arch/arm/kernel/time.c index d7d932c0286..d6bd435a685 100644 --- a/arch/arm/kernel/time.c +++ b/arch/arm/kernel/time.c @@ -422,12 +422,14 @@ static int timer_dyn_tick_disable(void) void timer_dyn_reprogram(void) { struct dyn_tick_timer *dyn_tick = system_timer->dyn_tick; + unsigned long next, seq; - if (dyn_tick) { - write_seqlock(&xtime_lock); - if (dyn_tick->state & DYN_TICK_ENABLED) + if (dyn_tick && (dyn_tick->state & DYN_TICK_ENABLED)) { + next = next_timer_interrupt(); + do { + seq = read_seqbegin(&xtime_lock); dyn_tick->reprogram(next_timer_interrupt() - jiffies); - write_sequnlock(&xtime_lock); + } while (read_seqretry(&xtime_lock, seq)); } } diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h index 6361544bb6a..6401c31d6ad 100644 --- a/include/linux/hrtimer.h +++ b/include/linux/hrtimer.h @@ -116,6 +116,10 @@ extern int hrtimer_try_to_cancel(struct hrtimer *timer); extern ktime_t hrtimer_get_remaining(const struct hrtimer *timer); extern int hrtimer_get_res(const clockid_t which_clock, struct timespec *tp); +#ifdef CONFIG_NO_IDLE_HZ +extern ktime_t hrtimer_get_next_event(void); +#endif + static inline int hrtimer_active(const struct hrtimer *timer) { return timer->state == HRTIMER_PENDING; diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c index 5ae51f1bc7c..14bc9cfa639 100644 --- a/kernel/hrtimer.c +++ b/kernel/hrtimer.c @@ -505,6 +505,41 @@ ktime_t hrtimer_get_remaining(const struct hrtimer *timer) return rem; } +#ifdef CONFIG_NO_IDLE_HZ +/** + * hrtimer_get_next_event - get the time until next expiry event + * + * Returns the delta to the next expiry event or KTIME_MAX if no timer + * is pending. + */ +ktime_t hrtimer_get_next_event(void) +{ + struct hrtimer_base *base = __get_cpu_var(hrtimer_bases); + ktime_t delta, mindelta = { .tv64 = KTIME_MAX }; + unsigned long flags; + int i; + + for (i = 0; i < MAX_HRTIMER_BASES; i++, base++) { + struct hrtimer *timer; + + spin_lock_irqsave(&base->lock, flags); + if (!base->first) { + spin_unlock_irqrestore(&base->lock, flags); + continue; + } + timer = rb_entry(base->first, struct hrtimer, node); + delta.tv64 = timer->expires.tv64; + spin_unlock_irqrestore(&base->lock, flags); + delta = ktime_sub(delta, base->get_time()); + if (delta.tv64 < mindelta.tv64) + mindelta.tv64 = delta.tv64; + } + if (mindelta.tv64 < 0) + mindelta.tv64 = 0; + return mindelta; +} +#endif + /** * hrtimer_init - initialize a timer to the given clock * diff --git a/kernel/timer.c b/kernel/timer.c index fc6646fd5aa..8256f3f5ec0 100644 --- a/kernel/timer.c +++ b/kernel/timer.c @@ -489,9 +489,21 @@ unsigned long next_timer_interrupt(void) struct list_head *list; struct timer_list *nte; unsigned long expires; + unsigned long hr_expires = MAX_JIFFY_OFFSET; + ktime_t hr_delta; tvec_t *varray[4]; int i, j; + hr_delta = hrtimer_get_next_event(); + if (hr_delta.tv64 != KTIME_MAX) { + struct timespec tsdelta; + tsdelta = ktime_to_timespec(hr_delta); + hr_expires = timespec_to_jiffies(&tsdelta); + if (hr_expires < 3) + return hr_expires + jiffies; + } + hr_expires += jiffies; + base = &__get_cpu_var(tvec_bases); spin_lock(&base->t_base.lock); expires = base->timer_jiffies + (LONG_MAX >> 1); @@ -542,6 +554,10 @@ found: } } spin_unlock(&base->t_base.lock); + + if (time_before(hr_expires, expires)) + return hr_expires; + return expires; } #endif |