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Date: Mon, 26 Mar 2012 19:04:43 +0200
From: Oleg Nesterov <oleg@redhat.com>
To: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Anton Vorontsov <anton.vorontsov@linaro.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Russell King <linux@arm.linux.org.uk>,
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Subject: Re: [PATCH v2.1 01/10] cpu: Introduce clear_tasks_mm_cpumask()
	helper
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On 03/26, Peter Zijlstra wrote:
>
> On Sun, 2012-03-25 at 19:42 +0200, Oleg Nesterov wrote:
> > __cpu_disable() is called by __stop_machine(), we know that nobody
> > can preempt us and other CPUs can do nothing.
>
> It would be very good to not rely on that though,

Yes, yes, perhaps I wasn't clear but I think the patches are fine.

> I would love to get
> rid of the stop_machine usage in cpu hotplug some day.

Interesting... Why? I mean, why do you dislike stop_machine() in
_cpu_down() ? Just curious.

Oleg.