/*
* The timer is locked, fire it and arrange for its reload.
*/
static void cpu_timer_fire(struct k_itimer *timer)
{
if ((timer->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE) {
/*
* User don't want any signal.
*/
timer->it.cpu.expires = 0;
} else if (unlikely(timer->sigq == NULL)) {
/*
* This a special case for clock_nanosleep,
* not a normal timer from sys_timer_create.
*/
wake_up_process(timer->it_process);
timer->it.cpu.expires = 0;
} else if (timer->it.cpu.incr == 0) {
/*
* One-shot timer. Clear it as soon as it's fired.
*/
posix_timer_event(timer, 0);
timer->it.cpu.expires = 0;
} else if (posix_timer_event(timer, ++timer->it_requeue_pending)) {
/*
* The signal did not get queued because the signal
* was ignored, so we won't get any callback to
* reload the timer. But we need to keep it
* ticking in case the signal is deliverable next time.
*/
posix_cpu_timer_schedule(timer);
}
}
/**
* alarm_handle_timer - Callback for posix timers
* @alarm: alarm that fired
*
* Posix timer callback for expired alarm timers.
*/
static void alarm_handle_timer(struct alarm *alarm)
{
struct k_itimer *ptr = container_of(alarm, struct k_itimer,
it.alarmtimer);
if (posix_timer_event(ptr, 0) != 0)
ptr->it_overrun++;
}
/*
* This function gets called when a POSIX.1b interval timer expires. It
* is used as a callback from the kernel internal timer. The
* run_timer_list code ALWAYS calls with interrupts on.
* This code is for CLOCK_REALTIME* and CLOCK_MONOTONIC* timers.
*/
static int posix_timer_fn(void *data)
{
struct k_itimer *timr = data;
unsigned long flags;
int si_private = 0;
int ret = HRTIMER_NORESTART;
spin_lock_irqsave(&timr->it_lock, flags);
if (timr->it.real.interval.tv64 != 0)
si_private = ++timr->it_requeue_pending;
if (posix_timer_event(timr, si_private)) {
/*
* signal was not sent because of sig_ignor
* we will not get a call back to restart it AND
* it should be restarted.
*/
if (timr->it.real.interval.tv64 != 0) {
timr->it_overrun +=
hrtimer_forward(&timr->it.real.timer,
timr->it.real.interval);
ret = HRTIMER_RESTART;
}
}
unlock_timer(timr, flags);
return ret;
}
static enum hrtimer_restart posix_timer_fn(struct hrtimer *timer)
{
struct k_itimer *timr;
unsigned long flags;
int si_private = 0;
enum hrtimer_restart ret = HRTIMER_NORESTART;
timr = container_of(timer, struct k_itimer, it.real.timer);
spin_lock_irqsave(&timr->it_lock, flags);
if (timr->it.real.interval.tv64 != 0)
si_private = ++timr->it_requeue_pending;
if (posix_timer_event(timr, si_private)) {
if (timr->it.real.interval.tv64 != 0) {
ktime_t now = hrtimer_cb_get_time(timer);
#ifdef CONFIG_HIGH_RES_TIMERS
{
ktime_t kj = ktime_set(0, NSEC_PER_SEC / HZ);
if (timr->it.real.interval.tv64 < kj.tv64)
now = ktime_add(now, kj);
}
#endif
timr->it_overrun += (unsigned int)
hrtimer_forward(timer, now,
timr->it.real.interval);
ret = HRTIMER_RESTART;
++timr->it_requeue_pending;
}
}
unlock_timer(timr, flags);
return ret;
}
/*
* This function gets called when a POSIX.1b interval timer expires. It
* is used as a callback from the kernel internal timer. The
* run_timer_list code ALWAYS calls with interrupts on.
* This code is for CLOCK_REALTIME* and CLOCK_MONOTONIC* timers.
*/
static enum hrtimer_restart posix_timer_fn(struct hrtimer *timer)
{
struct k_itimer *timr;
unsigned long flags;
int si_private = 0;
enum hrtimer_restart ret = HRTIMER_NORESTART;
timr = container_of(timer, struct k_itimer, it.real.timer);
spin_lock_irqsave(&timr->it_lock, flags);
if (timr->it.real.interval.tv64 != 0)
si_private = ++timr->it_requeue_pending;
if (posix_timer_event(timr, si_private)) {
/*
* signal was not sent because of sig_ignor
* we will not get a call back to restart it AND
* it should be restarted.
*/
if (timr->it.real.interval.tv64 != 0) {
ktime_t now = hrtimer_cb_get_time(timer);
/*
* FIXME: What we really want, is to stop this
* timer completely and restart it in case the
* SIG_IGN is removed. This is a non trivial
* change which involves sighand locking
* (sigh !), which we don't want to do late in
* the release cycle.
*
* For now we just let timers with an interval
* less than a jiffie expire every jiffie to
* avoid softirq starvation in case of SIG_IGN
* and a very small interval, which would put
* the timer right back on the softirq pending
* list. By moving now ahead of time we trick
* hrtimer_forward() to expire the timer
* later, while we still maintain the overrun
* accuracy, but have some inconsistency in
* the timer_gettime() case. This is at least
* better than a starved softirq. A more
* complex fix which solves also another related
* inconsistency is already in the pipeline.
*/
#ifdef CONFIG_HIGH_RES_TIMERS
{
ktime_t kj = ktime_set(0, NSEC_PER_SEC / HZ);
if (timr->it.real.interval.tv64 < kj.tv64)
now = ktime_add(now, kj);
}
#endif
timr->it_overrun += (unsigned int)
hrtimer_forward(timer, now,
timr->it.real.interval);
ret = HRTIMER_RESTART;
++timr->it_requeue_pending;
}
}
unlock_timer(timr, flags);
return ret;
}
