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Date: Fri, 2 Dec 2011 01:38:36 +0400
From: Cyrill Gorcunov <gorcunov@gmail.com>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>,
        linux-kernel@vger.kernel.org, Tejun Heo <tj@kernel.org>,
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        Serge Hallyn <serge.hallyn@canonical.com>,
        Pavel Emelyanov <xemul@parallels.com>,
        Vasiliy Kulikov <segoon@openwall.com>
Subject: Re: [rfc 2/3] fs, proc: Introduce the Children: line in
 /proc/<pid>/status
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On Thu, Dec 01, 2011 at 01:29:11PM -0800, Andrew Morton wrote:
> 
> That's a potentially very long hold time for tasklist_lock, and
> userspace can invoke this at a high frequency.  Not good.
> 
> I think this can all be done under rcu_read_lock() with
> list_for_each_entry_rcu().
> 

Yeah, good point, thanks Andrew!

	Cyrill