Re: [PATCH -next] sched/core: Fix the bug that traversal in sched_group_cookie_match is wrong

From: Peter Zijlstra
Date: Mon Oct 10 2022 - 03:43:16 EST


On Sat, Oct 08, 2022 at 10:27:09AM +0800, Lin Shengwang wrote:
> In commit 97886d9dcd86 ("sched: Migration changes for core scheduling"),
> sched_group_cookie_match() was added to help finding cookie matched
> group, but was inconsistent with the actual purpose.
>
> Using cpu_rq(cpu) instead of rq to fix the bug.
>
> Fixes: 97886d9dcd86 ("sched: Migration changes for core scheduling")
> Signed-off-by: Lin Shengwang <linshengwang1@xxxxxxxxxx>
> ---
> kernel/sched/sched.h | 18 +++++++++---------
> 1 file changed, 9 insertions(+), 9 deletions(-)
>
> diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
> index 23c6f9f42ba1..1ba602139840 100644
> --- a/kernel/sched/sched.h
> +++ b/kernel/sched/sched.h

> @@ -1269,7 +1277,7 @@ static inline bool sched_group_cookie_match(struct rq *rq,
> return true;
>
> for_each_cpu_and(cpu, sched_group_span(group), p->cpus_ptr) {
> - if (sched_core_cookie_match(rq, p))
> + if (sched_core_cookie_match(cpu_rq(cpu), p))
> return true;

Urgh.. Thanks!