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Subject: Re: [PATCH -tip] cpuacct: Make cpuacct hierarchy walk in
 cpuacct_charge() safe when rcupreempt is used.
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
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Date: Tue, 17 Mar 2009 14:26:01 +0100
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On Tue, 2009-03-17 at 18:42 +0530, Balbir Singh wrote:

> I'd like to get the patches in -tip and see the results, I would
> recommend using percpu_counter_sum() while reading the data as an
> enhancement to this patch. If user space does not overwhelm with a lot
> of reads, sum would work out better.

You trust userspace? I'd rather not.