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Subject: Re: [PATCH] cpuacct: add a branch prediction
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
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Date: Thu, 26 Feb 2009 11:44:36 +0100
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On Thu, 2009-02-26 at 19:28 +0900, KAMEZAWA Hiroyuki wrote:

> Taking hierarchy mutex while reading will make read-side stable.

We're talking about scheduling here, taking a mutex to stop scheduling
won't work, nor will it be acceptible to use anything that will.