Re: [PATCH v2 2/2] sched/fair: use lsub_positive in cpu_util_next()
From: Dietmar Eggemann
Date: Thu Feb 25 2021 - 06:47:40 EST
On 25/02/2021 09:36, vincent.donnefort@xxxxxxx wrote:
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From: Vincent Donnefort <vincent.donnefort@xxxxxxx>
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The sub_positive local version is saving an explicit load-store and is
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enough for the cpu_util_next() usage.
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Signed-off-by: Vincent Donnefort <vincent.donnefort@xxxxxxx>
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diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
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index 146ac9fec4b6..1364f8b95214 100644
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--- a/kernel/sched/fair.c
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+++ b/kernel/sched/fair.c
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@@ -6525,7 +6525,7 @@ static unsigned long cpu_util_next(int cpu, struct task_struct *p, int dst_cpu)
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* util_avg should already be correct.
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*/
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if (task_cpu(p) == cpu && dst_cpu != cpu)
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- sub_positive(&util, task_util(p));
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+ lsub_positive(&util, task_util(p));
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else if (task_cpu(p) != cpu && dst_cpu == cpu)
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util += task_util(p);
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@xxxxxxx>