diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h index cf5cfdf8d61304b319486724f9e0ec7515b63148..089bfb1fa01a771d7c11ee7de4227deb88d29b00 100644 --- a/include/linux/hrtimer.h +++ b/include/linux/hrtimer.h @@ -49,8 +49,6 @@ struct hrtimer_base; * struct hrtimer - the basic hrtimer structure * * @node: red black tree node for time ordered insertion - * @list: list head for easier access to the time ordered list, - * without walking the red black tree. * @expires: the absolute expiry time in the hrtimers internal * representation. The time is related to the clock on * which the timer is based. @@ -63,7 +61,6 @@ struct hrtimer_base; */ struct hrtimer { struct rb_node node; - struct list_head list; ktime_t expires; enum hrtimer_state state; int (*function)(void *); @@ -78,7 +75,7 @@ struct hrtimer { * to a base on another cpu. * @lock: lock protecting the base and associated timers * @active: red black tree root node for the active timers - * @pending: list of pending timers for simple time ordered access + * @first: pointer to the timer node which expires first * @resolution: the resolution of the clock, in nanoseconds * @get_time: function to retrieve the current time of the clock * @curr_timer: the timer which is executing a callback right now @@ -87,8 +84,8 @@ struct hrtimer_base { clockid_t index; spinlock_t lock; struct rb_root active; - struct list_head pending; - unsigned long resolution; + struct rb_node *first; + ktime_t resolution; ktime_t (*get_time)(void); struct hrtimer *curr_timer; }; @@ -125,8 +122,7 @@ static inline int hrtimer_active(const struct hrtimer *timer) } /* Forward a hrtimer so it expires after now: */ -extern unsigned long hrtimer_forward(struct hrtimer *timer, - const ktime_t interval); +extern unsigned long hrtimer_forward(struct hrtimer *timer, ktime_t interval); /* Precise sleep: */ extern long hrtimer_nanosleep(struct timespec *rqtp, diff --git a/include/linux/ktime.h b/include/linux/ktime.h index 222a047cc145e8d25c8d68894c86bc390d2a929b..1bd6552cc34134c4e19d5565e992fc91b9785910 100644 --- a/include/linux/ktime.h +++ b/include/linux/ktime.h @@ -272,8 +272,8 @@ static inline u64 ktime_to_ns(const ktime_t kt) * idea of the (in)accuracy of timers. Timer values are rounded up to * this resolution values. */ -#define KTIME_REALTIME_RES (NSEC_PER_SEC/HZ) -#define KTIME_MONOTONIC_RES (NSEC_PER_SEC/HZ) +#define KTIME_REALTIME_RES (ktime_t){ .tv64 = TICK_NSEC } +#define KTIME_MONOTONIC_RES (ktime_t){ .tv64 = TICK_NSEC } /* Get the monotonic time in timespec format: */ extern void ktime_get_ts(struct timespec *ts); diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c index f073a2461faa0b2090c4094215aa9d7804882eae..04ccab099e84e3ce01125a540e02f49d216f5943 100644 --- a/kernel/hrtimer.c +++ b/kernel/hrtimer.c @@ -275,7 +275,7 @@ void unlock_hrtimer_base(const struct hrtimer *timer, unsigned long *flags) * The number of overruns is added to the overrun field. */ unsigned long -hrtimer_forward(struct hrtimer *timer, const ktime_t interval) +hrtimer_forward(struct hrtimer *timer, ktime_t interval) { unsigned long orun = 1; ktime_t delta, now; @@ -287,6 +287,9 @@ hrtimer_forward(struct hrtimer *timer, const ktime_t interval) if (delta.tv64 < 0) return 0; + if (interval.tv64 < timer->base->resolution.tv64) + interval.tv64 = timer->base->resolution.tv64; + if (unlikely(delta.tv64 >= interval.tv64)) { nsec_t incr = ktime_to_ns(interval); @@ -314,7 +317,6 @@ hrtimer_forward(struct hrtimer *timer, const ktime_t interval) static void enqueue_hrtimer(struct hrtimer *timer, struct hrtimer_base *base) { struct rb_node **link = &base->active.rb_node; - struct list_head *prev = &base->pending; struct rb_node *parent = NULL; struct hrtimer *entry; @@ -330,22 +332,23 @@ static void enqueue_hrtimer(struct hrtimer *timer, struct hrtimer_base *base) */ if (timer->expires.tv64 < entry->expires.tv64) link = &(*link)->rb_left; - else { + else link = &(*link)->rb_right; - prev = &entry->list; - } } /* - * Insert the timer to the rbtree and to the sorted list: + * Insert the timer to the rbtree and check whether it + * replaces the first pending timer */ rb_link_node(&timer->node, parent, link); rb_insert_color(&timer->node, &base->active); - list_add(&timer->list, prev); timer->state = HRTIMER_PENDING; -} + if (!base->first || timer->expires.tv64 < + rb_entry(base->first, struct hrtimer, node)->expires.tv64) + base->first = &timer->node; +} /* * __remove_hrtimer - internal function to remove a timer @@ -355,9 +358,11 @@ static void enqueue_hrtimer(struct hrtimer *timer, struct hrtimer_base *base) static void __remove_hrtimer(struct hrtimer *timer, struct hrtimer_base *base) { /* - * Remove the timer from the sorted list and from the rbtree: + * Remove the timer from the rbtree and replace the + * first entry pointer if necessary. */ - list_del(&timer->list); + if (base->first == &timer->node) + base->first = rb_next(&timer->node); rb_erase(&timer->node, &base->active); } @@ -516,9 +521,8 @@ int hrtimer_get_res(const clockid_t which_clock, struct timespec *tp) { struct hrtimer_base *bases; - tp->tv_sec = 0; bases = per_cpu(hrtimer_bases, raw_smp_processor_id()); - tp->tv_nsec = bases[which_clock].resolution; + *tp = ktime_to_timespec(bases[which_clock].resolution); return 0; } @@ -529,16 +533,17 @@ int hrtimer_get_res(const clockid_t which_clock, struct timespec *tp) static inline void run_hrtimer_queue(struct hrtimer_base *base) { ktime_t now = base->get_time(); + struct rb_node *node; spin_lock_irq(&base->lock); - while (!list_empty(&base->pending)) { + while ((node = base->first)) { struct hrtimer *timer; int (*fn)(void *); int restart; void *data; - timer = list_entry(base->pending.next, struct hrtimer, list); + timer = rb_entry(node, struct hrtimer, node); if (now.tv64 <= timer->expires.tv64) break; @@ -732,7 +737,6 @@ static void __devinit init_hrtimers_cpu(int cpu) for (i = 0; i < MAX_HRTIMER_BASES; i++) { spin_lock_init(&base->lock); - INIT_LIST_HEAD(&base->pending); base++; } }