Messages in this thread Patch in this message | | | From | Tao Zhou <> | Subject | [PATCH] sched/fair: Check idle_cpu in select_idle_core/cpu() | Date | Sun, 10 Oct 2021 02:09:41 +0800 |
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In select_idle_core(), the idle core returned may have no cpu allowed. I think the idle core returned for the task is the one that can be allowed to run. I insist on this semantics.
In select_idle_cpu(), if select_idle_core() can not find the idle core, one reason is that the core is not allowed for the task, but the core itself is idle from the point of sds->has_idle_cores. I insist on this semantics.
No others, just two additional check. --- kernel/sched/fair.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index f6a05d9b5443..a44aca5095d3 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -6213,7 +6213,7 @@ static int select_idle_core(struct task_struct *p, int core, struct cpumask *cpu *idle_cpu = cpu; } - if (idle) + if (idle && *idle_cpu != -1) return core; cpumask_andnot(cpus, cpus, cpu_smt_mask(core)); @@ -6324,7 +6324,7 @@ static int select_idle_cpu(struct task_struct *p, struct sched_domain *sd, bool } } - if (has_idle_core) + if (has_idle_core && *idle_cpu != -1) set_idle_cores(target, false); if (sched_feat(SIS_PROP) && !has_idle_core) { -- 2.32.0
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