Commit a2d47777 authored Nov 12, 2008 by Balbir Singh Committed by Ingo Molnar Nov 12, 2008

sched: fix stale value in average load per task



Impact: fix load balancer load average calculation accuracy

cpu_avg_load_per_task() returns a stale value when nr_running is 0.
It returns an older stale (caculated when nr_running was non zero) value.

This patch returns and sets rq->avg_load_per_task to zero when nr_running
is 0.

Compile and boot tested on a x86_64 box.

Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

parent f21f237c

kernel/sched.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -1456,6 +1456,8 @@ static unsigned long cpu_avg_load_per_task(int cpu)

		if (rq->nr_running)
		rq->avg_load_per_task = rq->load.weight / rq->nr_running;
		else
		rq->avg_load_per_task = 0;

		return rq->avg_load_per_task;
		}

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