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Sender: Tejun Heo <htejun@gmail.com>
Date:   Fri, 19 Aug 2022 07:29:51 -1000
From:   Tejun Heo <tj@kernel.org>
To:     Lai Jiangshan <jiangshanlai@gmail.com>
Cc:     LKML <linux-kernel@vger.kernel.org>,
        Lai Jiangshan <jiangshan.ljs@antgroup.com>
Subject: Re: [RFC PATCH 7/8] workqueue: Remove the outer loop in
 maybe_create_worker()
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On Thu, Aug 18, 2022 at 10:44:02PM +0800, Lai Jiangshan wrote:
> On Wed, Aug 17, 2022 at 6:08 AM Tejun Heo <tj@kernel.org> wrote:
> >
> > On Thu, Aug 04, 2022 at 04:41:34PM +0800, Lai Jiangshan wrote:
> > > worker_thread() always does the recheck after getting the manager role,
> > > so the recheck in the maybe_create_worker() is unneeded and is removed.
> >
> > So, before if multiple workers need to be created, a single manager would
> > create them all. After, we'd end up daisy chaining, right? One manager
> > creates one worker and goes to process one work item. The new worker wakes
> > up and becomes the manager and creates another worker and so on. That
> > doesn't seem like a desirable behavior.
> >
> 
> The recheck is always in the same pool lock critical section, so the
> behavior isn't changed before/after this patch.

Ah, right you are.

Thanks.

-- 
tejun