[PATCH 26/28] sched: Fix volanomark performance regression

[stable-bot for Alex Shi]

Commit: b5482cfa1c95a188b3054fa33274806add91bbe5 upstream
Author: Alex Shi <alex.shi@xxxxxxxxx>
AuthorDate: Tue Nov 16 17:34:02 2010 +0800

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

Originally-by: Alex Shi <alex.shi@xxxxxxxxx>
Signed-off-by: Mike Galbraith <efault@xxxxxx>
Acked-by: Nikhil Rao <ncrao@xxxxxxxxxx>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
LKML-Reference: <1289928732.5169.211.camel@xxxxxxxxxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxx>
Signed-off-by: Mike Galbraith <efault@xxxxxx>
Acked-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
---
 kernel/sched.c |    4 ----
 1 files changed, 0 insertions(+), 4 deletions(-)

diff --git a/kernel/sched.c b/kernel/sched.c
index 445f2d1..ffd4f57 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -3326,10 +3326,6 @@ 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;
 }
 
 /*
-- 
1.7.4


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/