posix-timers: Move interval out of the union

Preparatory patch to unify the alarm timer and hrtimer based posix interval
timer handling.

The interval is used as a criteria for rearming decisions so moving it out
of the clock specific data structures allows later unification.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: John Stultz <john.stultz@linaro.org>
Link: http://lkml.kernel.org/r/20170530211656.563922908@linutronix.de

diff --git a/include/linux/posix-timers.h b/include/linux/posix-timers.h
index a372e7e..908048f 100644 (file)
--- a/include/linux/posix-timers.h
+++ b/include/linux/posix-timers.h
@@ -63,6 +63,7 @@ struct cpu_timer_list {
  * @it_requeue_pending:        Indicator that timer waits for being requeued on
  *                     signal delivery
  * @it_sigev_notify:   The notify word of sigevent struct for signal delivery
+ * @it_interval:       The interval for periodic timers
  * @it_signal:         Pointer to the creators signal struct
  * @it_pid:            The pid of the process/task targeted by the signal
  * @it_process:                The task to wakeup on clock_nanosleep (CPU timers)
@@ -80,6 +81,7 @@ struct k_itimer {
        int                     it_overrun_last;
        int                     it_requeue_pending;
        int                     it_sigev_notify;
+       ktime_t                 it_interval;
        struct signal_struct    *it_signal;
        union {
                struct pid              *it_pid;
@@ -89,12 +91,10 @@ struct k_itimer {
        union {
                struct {
                        struct hrtimer  timer;
-                       ktime_t         interval;
                } real;
                struct cpu_timer_list   cpu;
                struct {
                        struct alarm    alarmtimer;
-                       ktime_t         interval;
                } alarm;
                struct rcu_head         rcu;
        } it;

diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index 36855d6..5b8cf4b 100644 (file)
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -527,9 +527,8 @@ static enum alarmtimer_restart alarm_handle_timer(struct alarm *alarm,
        }
 
        /* Re-add periodic timers */
-       if (ptr->it.alarm.interval) {
-               ptr->it_overrun += alarm_forward(alarm, now,
-                                               ptr->it.alarm.interval);
+       if (ptr->it_interval) {
+               ptr->it_overrun += alarm_forward(alarm, now, ptr->it_interval);
                result = ALARMTIMER_RESTART;
        }
        spin_unlock_irqrestore(&ptr->it_lock, flags);
@@ -613,7 +612,7 @@ static void alarm_timer_get(struct k_itimer *timr,
                cur_setting->it_value.tv_nsec = 0;
        }
 
-       cur_setting->it_interval = ktime_to_timespec64(timr->it.alarm.interval);
+       cur_setting->it_interval = ktime_to_timespec64(timr->it_interval);
 }
 
 /**
@@ -662,14 +661,14 @@ static int alarm_timer_set(struct k_itimer *timr, int flags,
                return TIMER_RETRY;
 
        /* start the timer */
-       timr->it.alarm.interval = timespec64_to_ktime(new_setting->it_interval);
+       timr->it_interval = timespec64_to_ktime(new_setting->it_interval);
 
        /*
         * Rate limit to the tick as a hot fix to prevent DOS. Will be
         * mopped up later.
         */
-       if (timr->it.alarm.interval < TICK_NSEC)
-               timr->it.alarm.interval = TICK_NSEC;
+       if (timr->it_interval < TICK_NSEC)
+               timr->it_interval = TICK_NSEC;
 
        exp = timespec64_to_ktime(new_setting->it_value);
        /* Convert (if necessary) to absolute time */

diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index 79a00e0..7dd992c 100644 (file)
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -285,12 +285,12 @@ static void schedule_next_timer(struct k_itimer *timr)
 {
        struct hrtimer *timer = &timr->it.real.timer;
 
-       if (timr->it.real.interval == 0)
+       if (!timr->it_interval)
                return;
 
        timr->it_overrun += (unsigned int) hrtimer_forward(timer,
                                                timer->base->get_time(),
-                                               timr->it.real.interval);
+                                               timr->it_interval);
        hrtimer_restart(timer);
 }
 
@@ -375,7 +375,7 @@ static enum hrtimer_restart posix_timer_fn(struct hrtimer *timer)
        timr = container_of(timer, struct k_itimer, it.real.timer);
        spin_lock_irqsave(&timr->it_lock, flags);
 
-       if (timr->it.real.interval != 0)
+       if (timr->it_interval != 0)
                si_private = ++timr->it_requeue_pending;
 
        if (posix_timer_event(timr, si_private)) {
@@ -384,7 +384,7 @@ static enum hrtimer_restart posix_timer_fn(struct hrtimer *timer)
                 * we will not get a call back to restart it AND
                 * it should be restarted.
                 */
-               if (timr->it.real.interval != 0) {
+               if (timr->it_interval != 0) {
                        ktime_t now = hrtimer_cb_get_time(timer);
 
                        /*
@@ -413,13 +413,13 @@ static enum hrtimer_restart posix_timer_fn(struct hrtimer *timer)
                        {
                                ktime_t kj = NSEC_PER_SEC / HZ;
 
-                               if (timr->it.real.interval < kj)
+                               if (timr->it_interval < kj)
                                        now = ktime_add(now, kj);
                        }
 #endif
                        timr->it_overrun += (unsigned int)
                                hrtimer_forward(timer, now,
-                                               timr->it.real.interval);
+                                               timr->it_interval);
                        ret = HRTIMER_RESTART;
                        ++timr->it_requeue_pending;
                }
@@ -631,7 +631,7 @@ common_timer_get(struct k_itimer *timr, struct itimerspec64 *cur_setting)
 
        memset(cur_setting, 0, sizeof(*cur_setting));
 
-       iv = timr->it.real.interval;
+       iv = timr->it_interval;
 
        /* interval timer ? */
        if (iv)
@@ -732,7 +732,7 @@ common_timer_set(struct k_itimer *timr, int flags,
                common_timer_get(timr, old_setting);
 
        /* disable the timer */
-       timr->it.real.interval = 0;
+       timr->it_interval = 0;
        /*
         * careful here.  If smp we could be in the "fire" routine which will
         * be spinning as we hold the lock.  But this is ONLY an SMP issue.
@@ -755,7 +755,7 @@ common_timer_set(struct k_itimer *timr, int flags,
        hrtimer_set_expires(timer, timespec64_to_ktime(new_setting->it_value));
 
        /* Convert interval */
-       timr->it.real.interval = timespec64_to_ktime(new_setting->it_interval);
+       timr->it_interval = timespec64_to_ktime(new_setting->it_interval);
 
        /* SIGEV_NONE timers are not queued ! See common_timer_get */
        if (((timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE)) {
@@ -820,7 +820,7 @@ retry:
 
 static int common_timer_del(struct k_itimer *timer)
 {
-       timer->it.real.interval = 0;
+       timer->it_interval = 0;
 
        if (hrtimer_try_to_cancel(&timer->it.real.timer) < 0)
                return TIMER_RETRY;