Subject: sched: Remove resetting exec_start in put_prev_task_rt()
From: Hillf Danton <dhillf@gmail.com>
Date: Thu, 16 Jun 2011 21:55:21 -0400
Git-commit: 1812a643ccbfeb61a00a7f0d7219606e63d8815b
Patch-mainline: v3.2-rc1

There's no reason to clean the exec_start in put_prev_task_rt() as it is reset
when the task gets back to the run queue. This saves us doing a store() in the
fast path.

Signed-off-by: Hillf Danton <dhillf@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Yong Zhang <yong.zhang0@gmail.com>
Link: http://lkml.kernel.org/r/BANLkTimqWD=q6YnSDi-v9y=LMWecgEzEWg@mail.gmail.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Mike Galbraith <mgalbraith@suse.de>

---
 kernel/sched_rt.c |    1 -
 1 file changed, 1 deletion(-)

Index: linux-3.0-SLE11-SP2-3.0/kernel/sched_rt.c
===================================================================
--- linux-3.0-SLE11-SP2-3.0.orig/kernel/sched_rt.c
+++ linux-3.0-SLE11-SP2-3.0/kernel/sched_rt.c
@@ -1166,7 +1166,6 @@ static struct task_struct *pick_next_tas
 static void put_prev_task_rt(struct rq *rq, struct task_struct *p)
 {
 	update_curr_rt(rq);
-	p->se.exec_start = 0;
 
 	/*
 	 * The previous task needs to be made eligible for pushing

