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Date: Mon, 14 May 2012 11:17:25 -0700
From: Tejun Heo <tj@kernel.org>
To: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        "linux-mm@kvack.org" <linux-mm@kvack.org>,
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        Han Ying <yinghan@google.com>, Glauber Costa <glommer@parallels.com>,
        "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>,
        Hiroyuki Kamezawa <kamezawa.hiroyuki@gmail.com>,
        Linux Kernel <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 2/6] add res_counter_uncharge_until()
Message-ID: <20120514181725.GF2366@google.com>
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On Mon, May 14, 2012 at 07:32:42PM +0900, KAMEZAWA Hiroyuki wrote:
> [PATCH 2/6] memcg: add res_counter_uncharge_until()
> 
> From: Frederic Weisbecker <fweisbec@gmail.com>
> 
> At killing res_counter which is a child of other counter,
> we need to do
> 	res_counter_uncharge(child, xxx)
> 	res_counter_charge(parent, xxx)
> 
> This is not atomic and wasting cpu. This patch adds
> res_counter_uncharge_until(). This function's uncharge propagates
> to ancestors until specified res_counter.
> 
> 	res_counter_uncharge_until(child, parent, xxx)
> 
> Now, ops is atomic and efficient.
> 
> Changelog since v2
>  - removed unnecessary lines.
>  - added 'From' , this patch comes from his one.
> 
> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
> Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>

Acked-by: Tejun Heo <tj@kernel.org>

Thanks.

-- 
tejun