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Message-ID: <1332748746.16159.62.camel@twins>
Subject: Re: [PATCH v2.1 01/10] cpu: Introduce clear_tasks_mm_cpumask()
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From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Oleg Nesterov <oleg@redhat.com>
Cc: Anton Vorontsov <anton.vorontsov@linaro.org>,
        Andrew Morton <akpm@linux-foundation.org>,
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Date: Mon, 26 Mar 2012 09:59:06 +0200
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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, I would love to get
rid of the stop_machine usage in cpu hotplug some day.