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Date: Wed, 29 Jul 2009 23:21:25 +0200
From: Oleg Nesterov <oleg@redhat.com>
To: Andrew Morton <akpm@linux-foundation.org>, Ingo Molnar <mingo@elte.hu>,
       Lai Jiangshan <laijs@cn.fujitsu.com>,
       Rusty Russell <rusty@rustcorp.com.au>
Cc: linux-kernel@vger.kernel.org, Li Zefan <lizf@cn.fujitsu.com>,
       Miao Xie <miaox@cn.fujitsu.com>, Paul Menage <menage@google.com>,
       Peter Zijlstra <a.p.zijlstra@chello.nl>,
       Gautham R Shenoy <ego@in.ibm.com>
Subject: Re: + cpu_hotplug-dont-affect-current-tasks-affinity.patch added
	to -mm tree
Message-ID: <20090729212125.GA16970@redhat.com>
References: <20090729023302.GA8899@redhat.com>
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(add more CCs)

On 07/29, Oleg Nesterov wrote:
>
> But can't we make a much more simple patch ?
>
> Why should we play with set_cpus_allowed() at all? We can just migrate
> the caller of _cpu_down() before other tasks, right after take_cpu_down()
> does __cpu_disable()->remove_cpu_from_maps().
>
> No?
>
> Oleg.
>
> ------------------------------------------------------------------------
> Uncompiled, and we need to export move_task_off_dead_cpu(). Just to
> explain what I mean.

OK, tested. I think this should work. But first we should fix the bug
with cpusets. I'll send the patch in a minute...

Oleg.