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Date:   Tue, 12 Jan 2021 15:53:30 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     Lai Jiangshan <jiangshanlai@gmail.com>
Cc:     Valentin Schneider <valentin.schneider@arm.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        LKML <linux-kernel@vger.kernel.org>, Qian Cai <cai@redhat.com>,
        Vincent Donnefort <vincent.donnefort@arm.com>,
        Dexuan Cui <decui@microsoft.com>,
        Lai Jiangshan <laijs@linux.alibaba.com>,
        Paul McKenney <paulmck@kernel.org>,
        Vincent Guittot <vincent.guittot@linaro.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        Jens Axboe <axboe@kernel.dk>
Subject: Re: [PATCH -tip V3 0/8] workqueue: break affinity initiatively
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On Tue, Jan 12, 2021 at 12:33:03PM +0800, Lai Jiangshan wrote:
> > Well yes, but afaict the workqueue stuff hasn't been settled yet, and
> > the rcutorture patch Paul did was just plain racy and who knows what
> > other daft kthread users are out there. That and we're at -rc3.
> 
> I just send the V4 patchset for the workqueue.  Please take a look.

Yes, I've seen it. But I think this approach is smaller and simpler.

By distinguishing between geniuine per-cpu kthreads and kthreads that
happen to have a single CPU affinity, things become much simpler and
robust.