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Subject: Re: [PATCH 2/2] scheduler: cgroups cpuaccouting: Make cpuusage
 atomic
From: Peter Zijlstra <peterz@infradead.org>
To: Thomas Renninger <trenn@suse.de>
Cc: mike@android.com, linux-kernel@vger.kernel.org, lizf@cn.fujitsu.com,
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Date: Wed, 19 May 2010 21:02:23 +0200
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On Wed, 2010-05-19 at 20:58 +0200, Thomas Renninger wrote:
> and avoid locking on 32 bit.
> This resolves an ugly dependency in cgroups_cpuaccount.c
> to per_cpu runqueues lock variable.

While I totally agree with the sentiments here, atomic64_t isn't
available on all 32bit archs and is _terribly_ expensive on ARCH=i386.