From mboxrd@z Thu Jan  1 00:00:00 1970
From: Glauber Costa <glommer@parallels.com>
Subject: Re: [PATCH v3 3/6] expose fine-grained per-cpu data for cpuacct stats
Date: Wed, 30 May 2012 17:26:24 +0400
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To: Paul Turner <pjt@google.com>
Cc: linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, devel@openvz.org, Peter Zijlstra <a.p.zijlstra@chello.nl>, Tejun Heo <tj@kernel.org>, "Eric W. Biederman" <ebiederm@xmission.com>, handai.szj@gmail.com, Andrew.Phillips@lmax.com, Serge Hallyn <serge.hallyn@canonical.com>

On 05/30/2012 04:48 PM, Paul Turner wrote:
>> >  Now, if you guys are okay with a file per-cpu, I can do it as well.
>> >  It pollutes the filesystem, but at least protects against the fact that this
>> >  is kmalloc-backed.
>> >
> As I prefaced, I'm not sure there's much that can be trivially done
> about it.  This is really a fundamental limitation of how read_map()
> works.
>
> What we really need is a proper seq_file exposed through cftypes.

Tejun, would you be okay with an interface that exports somehow the raw 
seq_file in cgroups ?

This way we could call s_show for each cpu and get away with the memory 
usage problem, I presume