sched/fair: Fix the group_capacity computation

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Do away with 'phantom' cores due to N*frac(smt_power) >= 1 by limiting
the capacity to the actual number of cores.

The assumption of 1 < smt_power < 2 is an actual requirement because
of what SMT is so this should work regardless of the SMT
implementation.

It can still be defeated by creative use of cpu hotplug, but if you're
one of those freaks, you get to live with it.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Vincent Guittot <vincent.guitto@linaro.org>
Link: http://lkml.kernel.org/n/tip-dczmbi8tfgixacg1ji2av1un@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

...

This commit is contained in:

Peter Zijlstra 2013-08-28 12:40:38 +02:00 • committed by Ingo Molnar

parent b37d931685

commit c61037e905

1 changed files with 13 additions and 7 deletions

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kernel/sched/fair.c

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