From: Alex Shi <alex.shi@intel.com>
Date: Thu, 10 Feb 2011 09:23:29 +0000 (+0100)
Subject: sched: Fix volanomark performance regression
X-Git-Tag: firefly_0821_release~10186^2~460
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=82dd2a0c715ff88660278a3cb8a2d0efa866e234;p=firefly-linux-kernel-4.4.55.git

sched: Fix volanomark performance regression

Commit: b5482cfa1c95a188b3054fa33274806add91bbe5 upstream

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>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/kernel/sched.c b/kernel/sched.c
index 445f2d1101fc..ffd4f574008f 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;
 }
 
 /*