From: Oleg Nesterov <oleg@redhat.com>
Date: Thu, 16 Jan 2014 00:19:27 +0000 (-0800)
Subject: timers: Make internal_add_timer() update ->next_timer if ->active_timers == 0
X-Git-Tag: v3.15-rc1~153^2~28^2
X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=aea369b959bef10d235cd0714789cd8b0fe170b8;p=linux.git

timers: Make internal_add_timer() update ->next_timer if ->active_timers == 0

The internal_add_timer() function updates base->next_timer only if
timer->expires < base->next_timer. This is correct, but it also makes
sense to do the same if we add the first non-deferrable timer.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Tested-by: Mike Galbraith <bitbucket@online.de>
---

diff --git a/kernel/timer.c b/kernel/timer.c
index 0c638cf3d9d2..c0d8898fed98 100644
--- a/kernel/timer.c
+++ b/kernel/timer.c
@@ -404,9 +404,9 @@ static void internal_add_timer(struct tvec_base *base, struct timer_list *timer)
 	 * Update base->active_timers and base->next_timer
 	 */
 	if (!tbase_get_deferrable(timer->base)) {
-		if (time_before(timer->expires, base->next_timer))
+		if (!base->active_timers++ ||
+		    time_before(timer->expires, base->next_timer))
 			base->next_timer = timer->expires;
-		base->active_timers++;
 	}
 	base->all_timers++;
 }