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Sender: Tejun Heo <htejun@gmail.com>
Date:   Fri, 22 Jul 2022 19:16:20 -1000
From:   Tejun Heo <tj@kernel.org>
To:     Valentin Schneider <vschneid@redhat.com>
Cc:     Lai Jiangshan <jiangshanlai@gmail.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Frederic Weisbecker <frederic@kernel.org>,
        Juri Lelli <juri.lelli@redhat.com>,
        Phil Auld <pauld@redhat.com>,
        Marcelo Tosatti <mtosatti@redhat.com>
Subject: Re: [RFC PATCH] workqueue: Unbind workers before sending them to
 exit()
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On Thu, Jul 21, 2022 at 02:53:43PM +0100, Valentin Schneider wrote:
> > I think it needs something like task_set_cpumask_possible() which is
> > documented as being usable in (raw) spinlocks and set the task's cpumask
> > to cpu_possible_mask and let the later ttwu help migrate it to a
> > proper non-isolated CPU or let it keep running.
> 
> I'll see what I can come up with, thanks for the suggestion.

Alternatively, we can just kill all the idle kworkers on isolated cpus at
the end of the booting process.

Thanks.

-- 
tejun