alarmtimers: Remove period from alarm structure

Now that periodic alarmtimers are managed by the handler function,
remove the period value from the alarm structure and let the handlers
manage the interval on their own.

CC: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>

include/linux/alarmtimer.h

@@ -30,7 +30,6 @@ enum alarmtimer_restart {
  */
 struct alarm {
 	struct timerqueue_node	node;
-	ktime_t			period;
 	enum alarmtimer_restart	(*function)(struct alarm *, ktime_t now);
 	enum alarmtimer_type	type;
 	bool			enabled;
@@ -39,7 +38,7 @@ struct alarm {
 
 void alarm_init(struct alarm *alarm, enum alarmtimer_type type,
 		enum alarmtimer_restart (*function)(struct alarm *, ktime_t));
-void alarm_start(struct alarm *alarm, ktime_t start, ktime_t period);
+void alarm_start(struct alarm *alarm, ktime_t start);
 void alarm_cancel(struct alarm *alarm);
 
 u64 alarm_forward(struct alarm *alarm, ktime_t now, ktime_t interval);

include/linux/posix-timers.h

@@ -81,7 +81,10 @@ struct k_itimer {
 			unsigned long incr;
 			unsigned long expires;
 		} mmtimer;
-		struct alarm alarmtimer;
+		struct {
+			struct alarm alarmtimer;
+			ktime_t interval;
+		} alarm;
 		struct rcu_head rcu;
 	} it;
 };

kernel/time/alarmtimer.c

@@ -303,7 +303,6 @@ void alarm_init(struct alarm *alarm, enum alarmtimer_type type,
 		enum alarmtimer_restart (*function)(struct alarm *, ktime_t))
 {
 	timerqueue_init(&alarm->node);
-	alarm->period = ktime_set(0, 0);
 	alarm->function = function;
 	alarm->type = type;
 	alarm->enabled = 0;
@@ -313,9 +312,8 @@ void alarm_init(struct alarm *alarm, enum alarmtimer_type type,
  * alarm_start - Sets an alarm to fire
  * @alarm: ptr to alarm to set
  * @start: time to run the alarm
- * @period: period at which the alarm will recur
  */
-void alarm_start(struct alarm *alarm, ktime_t start, ktime_t period)
+void alarm_start(struct alarm *alarm, ktime_t start)
 {
 	struct alarm_base *base = &alarm_bases[alarm->type];
 	unsigned long flags;
@@ -324,7 +322,6 @@ void alarm_start(struct alarm *alarm, ktime_t start, ktime_t period)
 	if (alarm->enabled)
 		alarmtimer_remove(base, alarm);
 	alarm->node.expires = start;
-	alarm->period = period;
 	alarmtimer_enqueue(base, alarm);
 	alarm->enabled = 1;
 	spin_unlock_irqrestore(&base->lock, flags);
@@ -405,13 +402,14 @@ static enum alarmtimer_restart alarm_handle_timer(struct alarm *alarm,
 							ktime_t now)
 {
 	struct k_itimer *ptr = container_of(alarm, struct k_itimer,
-						it.alarmtimer);
+						it.alarm.alarmtimer);
 	if (posix_timer_event(ptr, 0) != 0)
 		ptr->it_overrun++;
 
 	/* Re-add periodic timers */
-	if (alarm->period.tv64) {
-		ptr->it_overrun += alarm_forward(alarm, now, alarm->period);
+	if (ptr->it.alarm.interval.tv64) {
+		ptr->it_overrun += alarm_forward(alarm, now,
+						ptr->it.alarm.interval);
 		return ALARMTIMER_RESTART;
 	}
 	return ALARMTIMER_NORESTART;
@@ -471,7 +469,7 @@ static int alarm_timer_create(struct k_itimer *new_timer)
 
 	type = clock2alarm(new_timer->it_clock);
 	base = &alarm_bases[type];
-	alarm_init(&new_timer->it.alarmtimer, type, alarm_handle_timer);
+	alarm_init(&new_timer->it.alarm.alarmtimer, type, alarm_handle_timer);
 	return 0;
 }
 
@@ -488,9 +486,9 @@ static void alarm_timer_get(struct k_itimer *timr,
 	memset(cur_setting, 0, sizeof(struct itimerspec));
 
 	cur_setting->it_interval =
-			ktime_to_timespec(timr->it.alarmtimer.period);
+			ktime_to_timespec(timr->it.alarm.interval);
 	cur_setting->it_value =
-			ktime_to_timespec(timr->it.alarmtimer.node.expires);
+		ktime_to_timespec(timr->it.alarm.alarmtimer.node.expires);
 	return;
 }
 
@@ -505,7 +503,7 @@ static int alarm_timer_del(struct k_itimer *timr)
 	if (!rtcdev)
 		return -ENOTSUPP;
 
-	alarm_cancel(&timr->it.alarmtimer);
+	alarm_cancel(&timr->it.alarm.alarmtimer);
 	return 0;
 }
 
@@ -529,12 +527,12 @@ static int alarm_timer_set(struct k_itimer *timr, int flags,
 		alarm_timer_get(timr, old_setting);
 
 	/* If the timer was already set, cancel it */
-	alarm_cancel(&timr->it.alarmtimer);
+	alarm_cancel(&timr->it.alarm.alarmtimer);
 
 	/* start the timer */
-	alarm_start(&timr->it.alarmtimer,
-			timespec_to_ktime(new_setting->it_value),
-			timespec_to_ktime(new_setting->it_interval));
+	timr->it.alarm.interval = timespec_to_ktime(new_setting->it_interval);
+	alarm_start(&timr->it.alarm.alarmtimer,
+			timespec_to_ktime(new_setting->it_value));
 	return 0;
 }
 
@@ -567,7 +565,7 @@ static int alarmtimer_do_nsleep(struct alarm *alarm, ktime_t absexp)
 	alarm->data = (void *)current;
 	do {
 		set_current_state(TASK_INTERRUPTIBLE);
-		alarm_start(alarm, absexp, ktime_set(0, 0));
+		alarm_start(alarm, absexp);
 		if (likely(alarm->data))
 			schedule();