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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>
Cc: Bharata B Rao <bharata.rao@gmail.com>, Li Zefan <lizf@cn.fujitsu.com>,
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Date: Thu, 26 Feb 2009 12:22:25 +0100
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On Thu, 2009-02-26 at 19:55 +0900, KAMEZAWA Hiroyuki wrote:
> Peter Zijlstra wrote：
> > 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.
> >
> I'm sorry but I thought we are talking about cpuacct subsystem and not
> cpu subsystem....cpuacct subsystem's information is used for schedule ?

Not used for scheduling, but directly generated by it.