From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrea Righi <arighi-vWjgImWzx8FBDgjK7y7TUQ@public.gmane.org>
Subject: Re: [PATCH -mmotm 1/5] memcg: disable irq at page cgroup lock
Date: Mon, 15 Mar 2010 11:00:25 +0100
Message-ID: <20100315100024.GA1653__49710.6287083172$1268647363$gmane$org@linux.develer.com>
References: <1268609202-15581-1-git-send-email-arighi@develer.com>
	<1268609202-15581-2-git-send-email-arighi@develer.com>
	<20100315090638.ee416d93.kamezawa.hiroyu@jp.fujitsu.com>
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Return-path: <containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org>
Content-Disposition: inline
In-Reply-To: <20100315090638.ee416d93.kamezawa.hiroyu-+CUm20s59erQFUHtdCDX3A@public.gmane.org>
List-Unsubscribe: <https://lists.linux-foundation.org/mailman/listinfo/containers>,
	<mailto:containers-request-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org?subject=unsubscribe>
List-Archive: <http://lists.linux-foundation.org/pipermail/containers>
List-Post: <mailto:containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org>
List-Help: <mailto:containers-request-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org?subject=help>
List-Subscribe: <https://lists.linux-foundation.org/mailman/listinfo/containers>,
	<mailto:containers-request-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org?subject=subscribe>
Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org
Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org
To: KAMEZAWA Hiroyuki <kamezawa.hiroyu-+CUm20s59erQFUHtdCDX3A@public.gmane.org>
Cc: Daisuke Nishimura <nishimura-YQH0OdQVrdy45+QrQBaojngSJqDPrsil@public.gmane.org>, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Trond Myklebust <trond.myklebust-41N18TsMXrtuMpJDpNschA@public.gmane.org>, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, Suleiman Souhlal <suleiman-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>, Andrew Morton <akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>, containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, Vivek Goyal <vgoyal-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, Balbir Singh <balbir-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>
List-Id: containers.vger.kernel.org

On Mon, Mar 15, 2010 at 09:06:38AM +0900, KAMEZAWA Hiroyuki wrote:
> On Mon, 15 Mar 2010 00:26:38 +0100
> Andrea Righi <arighi-vWjgImWzx8FBDgjK7y7TUQ@public.gmane.org> wrote:
> 
> > From: KAMEZAWA Hiroyuki <kamezawa.hiroyu-+CUm20s59erQFUHtdCDX3A@public.gmane.org>
> > 
> > Now, file-mapped is maintaiend. But more generic update function
> > will be needed for dirty page accounting.
> > 
> > For accountig page status, we have to guarantee lock_page_cgroup()
> > will be never called under tree_lock held.
> > To guarantee that, we use trylock at updating status.
> > By this, we do fuzzy accounting, but in almost all case, it's correct.
> > 
> > Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu-+CUm20s59erQFUHtdCDX3A@public.gmane.org>
> 
> Bad patch title...."use trylock for safe accounting in some contexts" ?

OK, sounds better. I just copy & paste the email subject, but the title
was probably related to the old lock_page_cgroup()+irq_disable patch.

Thanks,
-Andrea