Re: [RFC PATCH v3 1/3] workqueue: Hold wq_pool_mutex while affining tasks to wq_unbound_cpumask

From: Tejun Heo
Date: Mon Aug 15 2022 - 23:33:22 EST


On Wed, Aug 03, 2022 at 11:40:28AM +0800, Lai Jiangshan wrote:
> From df7b4672db4dfd3e480b1873b9d346e8a7dfc69f Mon Sep 17 00:00:00 2001
> From: Lai Jiangshan <jiangshan.ljs@xxxxxxxxxxxx>
> Date: Wed, 3 Aug 2022 10:52:04 +0800
> Subject: [PATCH] workqueue: Protects wq_unbound_cpumask with
> wq_pool_attach_mutex
>
> When unbind_workers() reads wq_unbound_cpumask to set the affinity of
> freshly-unbound kworkers, it only holds wq_pool_attach_mutex. This isn't
> sufficient as wq_unbound_cpumask is only protected by wq_pool_mutex.
>
> Make wq_unbound_cpumask protected with wq_pool_attach_mutex and also
> remove the need of temporary saved_cpumask.
>
> Fixes: 10a5a651e3af ("workqueue: Restrict kworker in the offline CPU pool running on housekeeping CPUs")
> Reported-by: Valentin Schneider <vschneid@xxxxxxxxxx>
> Signed-off-by: Lai Jiangshan <jiangshan.ljs@xxxxxxxxxxxx>

This patch looks fine to me but is whitespace corrupted (two leading spaces
on all context lines). Can you please resend?

Thanks.

--
tejun