alarmtimer: Rename gettime() callback to get_ktime()

The upcoming support for time namespaces requires to have access to:

  - The time in a tasks time namespace for sys_clock_gettime()
  - The time in the root name space for common_timer_get()

struct alarm_base needs to follow the same naming convention, so rename
.gettime() callback into get_ktime() as a preparation for introducing
get_timespec().

Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191112012724.250792-8-dima@arista.com

kernel/time/alarmtimer.c

@@ -36,13 +36,13 @@
  * struct alarm_base - Alarm timer bases
  * @lock:		Lock for syncrhonized access to the base
  * @timerqueue:		Timerqueue head managing the list of events
- * @gettime:		Function to read the time correlating to the base
+ * @get_ktime:		Function to read the time correlating to the base
  * @base_clockid:	clockid for the base
  */
 static struct alarm_base {
 	spinlock_t		lock;
 	struct timerqueue_head	timerqueue;
-	ktime_t			(*gettime)(void);
+	ktime_t			(*get_ktime)(void);
 	clockid_t		base_clockid;
 } alarm_bases[ALARM_NUMTYPE];
 
@@ -207,7 +207,7 @@ static enum hrtimer_restart alarmtimer_fired(struct hrtimer *timer)
 	spin_unlock_irqrestore(&base->lock, flags);
 
 	if (alarm->function)
-		restart = alarm->function(alarm, base->gettime());
+		restart = alarm->function(alarm, base->get_ktime());
 
 	spin_lock_irqsave(&base->lock, flags);
 	if (restart != ALARMTIMER_NORESTART) {
@@ -217,15 +217,15 @@ static enum hrtimer_restart alarmtimer_fired(struct hrtimer *timer)
 	}
 	spin_unlock_irqrestore(&base->lock, flags);
 
-	trace_alarmtimer_fired(alarm, base->gettime());
+	trace_alarmtimer_fired(alarm, base->get_ktime());
 	return ret;
 
 }
 
 ktime_t alarm_expires_remaining(const struct alarm *alarm)
 {
 	struct alarm_base *base = &alarm_bases[alarm->type];
-	return ktime_sub(alarm->node.expires, base->gettime());
+	return ktime_sub(alarm->node.expires, base->get_ktime());
 }
 EXPORT_SYMBOL_GPL(alarm_expires_remaining);
 
@@ -270,7 +270,7 @@ static int alarmtimer_suspend(struct device *dev)
 		spin_unlock_irqrestore(&base->lock, flags);
 		if (!next)
 			continue;
-		delta = ktime_sub(next->expires, base->gettime());
+		delta = ktime_sub(next->expires, base->get_ktime());
 		if (!min || (delta < min)) {
 			expires = next->expires;
 			min = delta;
@@ -364,7 +364,7 @@ void alarm_start(struct alarm *alarm, ktime_t start)
 	hrtimer_start(&alarm->timer, alarm->node.expires, HRTIMER_MODE_ABS);
 	spin_unlock_irqrestore(&base->lock, flags);
 
-	trace_alarmtimer_start(alarm, base->gettime());
+	trace_alarmtimer_start(alarm, base->get_ktime());
 }
 EXPORT_SYMBOL_GPL(alarm_start);
 
@@ -377,7 +377,7 @@ void alarm_start_relative(struct alarm *alarm, ktime_t start)
 {
 	struct alarm_base *base = &alarm_bases[alarm->type];
 
-	start = ktime_add_safe(start, base->gettime());
+	start = ktime_add_safe(start, base->get_ktime());
 	alarm_start(alarm, start);
 }
 EXPORT_SYMBOL_GPL(alarm_start_relative);
@@ -414,7 +414,7 @@ int alarm_try_to_cancel(struct alarm *alarm)
 		alarmtimer_dequeue(base, alarm);
 	spin_unlock_irqrestore(&base->lock, flags);
 
-	trace_alarmtimer_cancel(alarm, base->gettime());
+	trace_alarmtimer_cancel(alarm, base->get_ktime());
 	return ret;
 }
 EXPORT_SYMBOL_GPL(alarm_try_to_cancel);
@@ -474,7 +474,7 @@ u64 alarm_forward_now(struct alarm *alarm, ktime_t interval)
 {
 	struct alarm_base *base = &alarm_bases[alarm->type];
 
-	return alarm_forward(alarm, base->gettime(), interval);
+	return alarm_forward(alarm, base->get_ktime(), interval);
 }
 EXPORT_SYMBOL_GPL(alarm_forward_now);
 
@@ -500,7 +500,7 @@ static void alarmtimer_freezerset(ktime_t absexp, enum alarmtimer_type type)
 		return;
 	}
 
-	delta = ktime_sub(absexp, base->gettime());
+	delta = ktime_sub(absexp, base->get_ktime());
 
 	spin_lock_irqsave(&freezer_delta_lock, flags);
 	if (!freezer_delta || (delta < freezer_delta)) {
@@ -632,7 +632,7 @@ static void alarm_timer_arm(struct k_itimer *timr, ktime_t expires,
 	struct alarm_base *base = &alarm_bases[alarm->type];
 
 	if (!absolute)
-		expires = ktime_add_safe(expires, base->gettime());
+		expires = ktime_add_safe(expires, base->get_ktime());
 	if (sigev_none)
 		alarm->node.expires = expires;
 	else
@@ -670,7 +670,7 @@ static int alarm_clock_get_timespec(clockid_t which_clock, struct timespec64 *tp
 	if (!alarmtimer_get_rtcdev())
 		return -EINVAL;
 
-	*tp = ktime_to_timespec64(base->gettime());
+	*tp = ktime_to_timespec64(base->get_ktime());
 	return 0;
 }
 
@@ -747,7 +747,7 @@ static int alarmtimer_do_nsleep(struct alarm *alarm, ktime_t absexp,
 		struct timespec64 rmt;
 		ktime_t rem;
 
-		rem = ktime_sub(absexp, alarm_bases[type].gettime());
+		rem = ktime_sub(absexp, alarm_bases[type].get_ktime());
 
 		if (rem <= 0)
 			return 0;
@@ -816,7 +816,7 @@ static int alarm_timer_nsleep(const clockid_t which_clock, int flags,
 	exp = timespec64_to_ktime(*tsreq);
 	/* Convert (if necessary) to absolute time */
 	if (flags != TIMER_ABSTIME) {
-		ktime_t now = alarm_bases[type].gettime();
+		ktime_t now = alarm_bases[type].get_ktime();
 
 		exp = ktime_add_safe(now, exp);
 	}
@@ -882,9 +882,9 @@ static int __init alarmtimer_init(void)
 
 	/* Initialize alarm bases */
 	alarm_bases[ALARM_REALTIME].base_clockid = CLOCK_REALTIME;
-	alarm_bases[ALARM_REALTIME].gettime = &ktime_get_real;
+	alarm_bases[ALARM_REALTIME].get_ktime = &ktime_get_real;
 	alarm_bases[ALARM_BOOTTIME].base_clockid = CLOCK_BOOTTIME;
-	alarm_bases[ALARM_BOOTTIME].gettime = &ktime_get_boottime;
+	alarm_bases[ALARM_BOOTTIME].get_ktime = &ktime_get_boottime;
 	for (i = 0; i < ALARM_NUMTYPE; i++) {
 		timerqueue_init_head(&alarm_bases[i].timerqueue);
 		spin_lock_init(&alarm_bases[i].lock);