Messages in this thread Patch in this message | | | Date | Wed, 21 Feb 2018 02:27:38 -0800 | From | tip-bot for Mel Gorman <> | Subject | [tip:sched/core] sched/fair: Avoid an unnecessary lookup of current CPU ID during wake_affine |
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Commit-ID: 7ebb66a12f85bc375beaf45ca900427fe47aa8f7 Gitweb: https://git.kernel.org/tip/7ebb66a12f85bc375beaf45ca900427fe47aa8f7 Author: Mel Gorman <mgorman@techsingularity.net> AuthorDate: Tue, 13 Feb 2018 13:37:25 +0000 Committer: Ingo Molnar <mingo@kernel.org> CommitDate: Wed, 21 Feb 2018 08:49:07 +0100
sched/fair: Avoid an unnecessary lookup of current CPU ID during wake_affine
The only caller of wake_affine() knows the CPU ID. Pass it in instead of rechecking it.
Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Giovanni Gherdovich <ggherdovich@suse.cz> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20180213133730.24064-2-mgorman@techsingularity.net Signed-off-by: Ingo Molnar <mingo@kernel.org> --- kernel/sched/fair.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 820f94c..0132572 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -5751,9 +5751,8 @@ wake_affine_weight(struct sched_domain *sd, struct task_struct *p, } static int wake_affine(struct sched_domain *sd, struct task_struct *p, - int prev_cpu, int sync) + int this_cpu, int prev_cpu, int sync) { - int this_cpu = smp_processor_id(); int target = nr_cpumask_bits; if (sched_feat(WA_IDLE)) @@ -6376,7 +6375,7 @@ select_task_rq_fair(struct task_struct *p, int prev_cpu, int sd_flag, int wake_f if (cpu == prev_cpu) goto pick_cpu; - new_cpu = wake_affine(affine_sd, p, prev_cpu, sync); + new_cpu = wake_affine(affine_sd, p, cpu, prev_cpu, sync); } if (sd && !(sd_flag & SD_BALANCE_FORK)) {
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