clockevent: simplify list operations

list_for_each_safe() suffices here.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kernel/time/clockevents.c

@@ -218,6 +218,8 @@ void clockevents_exchange_device(struct clock_event_device *old,
  */
 void clockevents_notify(unsigned long reason, void *arg)
 {
+	struct list_head *node, *tmp;
+
 	spin_lock(&clockevents_lock);
 	clockevents_do_notify(reason, arg);
 
@@ -227,13 +229,8 @@ void clockevents_notify(unsigned long reason, void *arg)
 		 * Unregister the clock event devices which were
 		 * released from the users in the notify chain.
 		 */
-		while (!list_empty(&clockevents_released)) {
-			struct clock_event_device *dev;
-
-			dev = list_entry(clockevents_released.next,
-					 struct clock_event_device, list);
-			list_del(&dev->list);
-		}
+		list_for_each_safe(node, tmp, &clockevents_released)
+			list_del(node);
 		break;
 	default:
 		break;