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Date: Wed, 24 Mar 2010 21:45:45 +0100
From: Oleg Nesterov <oleg@redhat.com>
To: Andrew Morton <akpm@linux-foundation.org>,
       Americo Wang <xiyou.wangcong@gmail.com>,
       Balbir Singh <balbir@in.ibm.com>,
       "Eric W. Biederman" <ebiederm@xmission.com>,
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       Ingo Molnar <mingo@elte.hu>, Peter Zijlstra <peterz@infradead.org>,
       Roland McGrath <roland@redhat.com>,
       Spencer Candland <spencer@bluehost.com>,
       Stanislaw Gruszka <sgruszka@redhat.com>
Cc: linux-kernel@vger.kernel.org
Subject: [RFC,PATCH 0/2] cputimers/proc: can't we make /proc/pid/stat less
	accurate?
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Mostly to provoke the discussion and untested, please comment.

In short: I do not actually know if /proc/pid/stat should be "really"
accurate wrt cpu accounting. I mean, I don't know how much /bin/top
and friends depend on xtime monotonicity.

However, it is sad that /proc/pid/stat iterates over ->thread_group
_twice_ under ->siglock.

Any thoughts?

Oleg.