diff options
| -rw-r--r-- | include/linux/alarmtimer.h | 34 | ||||
| -rw-r--r-- | kernel/time/alarmtimer.c | 21 |
2 files changed, 47 insertions, 8 deletions
diff --git a/include/linux/alarmtimer.h b/include/linux/alarmtimer.h index c854a8efa863..304124a6c982 100644 --- a/include/linux/alarmtimer.h +++ b/include/linux/alarmtimer.h @@ -18,6 +18,11 @@ enum alarmtimer_restart { ALARMTIMER_RESTART, }; + +#define ALARMTIMER_STATE_INACTIVE 0x00 +#define ALARMTIMER_STATE_ENQUEUED 0x01 +#define ALARMTIMER_STATE_CALLBACK 0x02 + /** * struct alarm - Alarm timer structure * @node: timerqueue node for adding to the event list this value @@ -32,7 +37,7 @@ struct alarm { struct timerqueue_node node; enum alarmtimer_restart (*function)(struct alarm *, ktime_t now); enum alarmtimer_type type; - bool enabled; + int state; void *data; }; @@ -43,4 +48,31 @@ void alarm_cancel(struct alarm *alarm); u64 alarm_forward(struct alarm *alarm, ktime_t now, ktime_t interval); +/* + * A alarmtimer is active, when it is enqueued into timerqueue or the + * callback function is running. + */ +static inline int alarmtimer_active(const struct alarm *timer) +{ + return timer->state != ALARMTIMER_STATE_INACTIVE; +} + +/* + * Helper function to check, whether the timer is on one of the queues + */ +static inline int alarmtimer_is_queued(struct alarm *timer) +{ + return timer->state & ALARMTIMER_STATE_ENQUEUED; +} + +/* + * Helper function to check, whether the timer is running the callback + * function + */ +static inline int alarmtimer_callback_running(struct alarm *timer) +{ + return timer->state & ALARMTIMER_STATE_CALLBACK; +} + + #endif diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c index 90935591dd44..5b14cc29b6a6 100644 --- a/kernel/time/alarmtimer.c +++ b/kernel/time/alarmtimer.c @@ -126,6 +126,8 @@ static struct rtc_device *alarmtimer_get_rtcdev(void) static void alarmtimer_enqueue(struct alarm_base *base, struct alarm *alarm) { timerqueue_add(&base->timerqueue, &alarm->node); + alarm->state |= ALARMTIMER_STATE_ENQUEUED; + if (&alarm->node == timerqueue_getnext(&base->timerqueue)) { hrtimer_try_to_cancel(&base->timer); hrtimer_start(&base->timer, alarm->node.expires, @@ -147,7 +149,12 @@ static void alarmtimer_remove(struct alarm_base *base, struct alarm *alarm) { struct timerqueue_node *next = timerqueue_getnext(&base->timerqueue); + if (!(alarm->state & ALARMTIMER_STATE_ENQUEUED)) + return; + timerqueue_del(&base->timerqueue, &alarm->node); + alarm->state &= ~ALARMTIMER_STATE_ENQUEUED; + if (next == &alarm->node) { hrtimer_try_to_cancel(&base->timer); next = timerqueue_getnext(&base->timerqueue); @@ -188,16 +195,18 @@ static enum hrtimer_restart alarmtimer_fired(struct hrtimer *timer) alarm = container_of(next, struct alarm, node); timerqueue_del(&base->timerqueue, &alarm->node); - alarm->enabled = 0; + alarm->state &= ~ALARMTIMER_STATE_ENQUEUED; + alarm->state |= ALARMTIMER_STATE_CALLBACK; spin_unlock_irqrestore(&base->lock, flags); if (alarm->function) restart = alarm->function(alarm, now); spin_lock_irqsave(&base->lock, flags); + alarm->state &= ~ALARMTIMER_STATE_CALLBACK; if (restart != ALARMTIMER_NORESTART) { timerqueue_add(&base->timerqueue, &alarm->node); - alarm->enabled = 1; + alarm->state |= ALARMTIMER_STATE_ENQUEUED; } } @@ -305,7 +314,7 @@ void alarm_init(struct alarm *alarm, enum alarmtimer_type type, timerqueue_init(&alarm->node); alarm->function = function; alarm->type = type; - alarm->enabled = 0; + alarm->state = ALARMTIMER_STATE_INACTIVE; } /** @@ -319,11 +328,10 @@ void alarm_start(struct alarm *alarm, ktime_t start) unsigned long flags; spin_lock_irqsave(&base->lock, flags); - if (alarm->enabled) + if (alarmtimer_active(alarm)) alarmtimer_remove(base, alarm); alarm->node.expires = start; alarmtimer_enqueue(base, alarm); - alarm->enabled = 1; spin_unlock_irqrestore(&base->lock, flags); } @@ -337,9 +345,8 @@ void alarm_cancel(struct alarm *alarm) unsigned long flags; spin_lock_irqsave(&base->lock, flags); - if (alarm->enabled) + if (alarmtimer_is_queued(alarm)) alarmtimer_remove(base, alarm); - alarm->enabled = 0; spin_unlock_irqrestore(&base->lock, flags); } |