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Date: Tue, 3 Mar 2009 18:04:39 +0900 (JST)
Subject: Re: [RFC][PATCH] remove rq->lock from cpuacct cgroup (Was Re:
 [PATCH] cpuacct: add a branch prediction
From: "KAMEZAWA Hiroyuki" <kamezawa.hiroyu@jp.fujitsu.com>
To: "Peter Zijlstra" <a.p.zijlstra@chello.nl>
Cc: "KAMEZAWA Hiroyuki" <kamezawa.hiroyu@jp.fujitsu.com>,
       paulmck@linux.vnet.ibm.com, "Bharata B Rao" <bharata.rao@gmail.com>,
       "Li Zefan" <lizf@cn.fujitsu.com>, "Ingo Molnar" <mingo@elte.hu>,
       "Paul Menage" <menage@google.com>,
       "Balbir Singh" <balbir@linux.vnet.ibm.com>,
       "LKML" <linux-kernel@vger.kernel.org>
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Peter Zijlstra wrote:
> On Tue, 2009-03-03 at 08:42 +0900, KAMEZAWA Hiroyuki wrote:
>
>> > Furthermore, if you want something like schedule_work_on() for each
>> cpu,
>> > there's schedule_on_each_cpu().
>> >
>> It can't pass arguments...Maybe I should use rq->lock here to reset
>> other cpu's value.
>
> Why bother with serializing the reset code at all?
>
  I don't think reset v.s. read is problem but reset v.s. increment
  (read-modify-write) can't be ?

> But there's always smp_call_function() I suppose.
>

Hmm, I'll find some simpler way.

Thanks,
-Kame


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