[tip:sched/urgent] sched: Fix volanomark performance regression

[tip-bot for Alex Shi <alex.shi@intel.com>]

Commit-ID:  b5482cfa1c95a188b3054fa33274806add91bbe5
Gitweb:     http://git.kernel.org/tip/b5482cfa1c95a188b3054fa33274806add91bbe5
Author:     Alex Shi <alex.shi@intel.com>
AuthorDate: Tue, 16 Nov 2010 17:34:02 +0800
Committer:  Ingo Molnar <mingo@elte.hu>
CommitDate: Thu, 18 Nov 2010 13:11:43 +0100

sched: Fix volanomark performance regression

Commit fab4762 triggers excessive idle balancing, causing a ~30% loss in
volanomark throughput. Remove idle balancing throttle reset.

Originally-by: Alex Shi <alex.shi@intel.com>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Acked-by: Nikhil Rao <ncrao@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1289928732.5169.211.camel@maggy.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 kernel/sched_fair.c |    4 ----
 1 files changed, 0 insertions(+), 4 deletions(-)

diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 52ab113..ba0556d 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -1758,10 +1758,6 @@ static void pull_task(struct rq *src_rq, struct task_struct *p,
 	set_task_cpu(p, this_cpu);
 	activate_task(this_rq, p, 0);
 	check_preempt_curr(this_rq, p, 0);
-
-	/* re-arm NEWIDLE balancing when moving tasks */
-	src_rq->avg_idle = this_rq->avg_idle = 2*sysctl_sched_migration_cost;
-	this_rq->idle_stamp = 0;
 }
 
 /*