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Date: Fri, 06 Feb 2009 11:10:26 +0800
From: Li Zefan <lizf@cn.fujitsu.com>
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CC: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>,
       Andrew Morton <akpm@linux-foundation.org>,
       "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
       "nishimura@mxp.nes.nec.co.jp" <nishimura@mxp.nes.nec.co.jp>,
       "linux-mm@kvack.org" <linux-mm@kvack.org>
Subject: Re: [-mm patch] Show memcg information during OOM (v3)
References: <20090203172135.GF918@balbir.in.ibm.com> <498BA857.3080809@cn.fujitsu.com>
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Li Zefan wrote:
>> +	mem_cgrp = memcg->css.cgroup;
>> +	task_cgrp = mem_cgroup_from_task(p)->css.cgroup;
> 
> I just noticed since v2, task's cgroup is also printed. Then 2 issues here:
> 
> 1. this is better: task_cgrp = task_subsys_state(p, mem_cgroup_subsys_id);

sorry, s/task_subsys_state/task_cgroup/

> 2. getting cgroup from a task should be protected by task_lock or rcu_read_lock,
>    so we can put the above statement inside rcu_read_lock below.