From mboxrd@z Thu Jan  1 00:00:00 1970
From: Glauber Costa <glommer@parallels.com>
Subject: Re: [PATCH 2/2] Explicitly call tcp creation and init from memcontrol.c
Date: Fri, 16 Dec 2011 06:06:34 +0400
Message-ID: <4EEAA7AA.3030209@parallels.com>
References: <1323941672-14324-1-git-send-email-glommer@parallels.com> <1323941672-14324-3-git-send-email-glommer@parallels.com> <20111216011316.8d58bc8f.kamezawa.hiroyu@jp.fujitsu.com> <20111216072050.4f49ac66.kamezawa.hiroyu@jp.fujitsu.com>
Mime-Version: 1.0
Content-Transfer-Encoding: 7bit
Return-path: <linux-kernel-owner@vger.kernel.org>
In-Reply-To: <20111216072050.4f49ac66.kamezawa.hiroyu@jp.fujitsu.com>
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <cgroups.vger.kernel.org>
Content-Type: text/plain; charset="us-ascii"; format="flowed"
To: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: davem@davemloft.net, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, cgroups@vger.kernel.org, Eric Dumazet <eric.dumazet@gmail.com>, Stephen Rothwell <sfr@canb.auug.org.au>

On 12/16/2011 02:20 AM, KAMEZAWA Hiroyuki wrote:
> On Fri, 16 Dec 2011 01:13:16 +0900
> KAMEZAWA Hiroyuki<kamezawa.hiroyu@jp.fujitsu.com>  wrote:
>
>> On Thu, 15 Dec 2011 13:34:32 +0400
>> Glauber Costa<glommer@parallels.com>  wrote:
>>
>>> Walking the proto_list holds a read_lock, which prevents us from doing
>>> allocations. Splitting the tcp create function into create + init is
>>> good, but it is not enough since create_files will do allocations as well
>>> (dentry ones, mostly).
>>>
>>> Since this does not involve any protocol state, I propose we call the tcp
>>> functions explicitly from memcontrol.c
>>>
>>> With this, we lose by now the ability of doing cgroup memcontrol for
>>> protocols that are loaded as modules. But at least the ones I have in mind
>>> won't really need it (tcp_ipv6 being the only one, but it uses the same data
>>> structures as tcp_ipv4). So I believe this to be the simpler solution to this
>>> problem.
>>>
>>> Signed-off-by: Glauber Costa<glommer@parallels.com>
>>> CC: Hiroyouki Kamezawa<kamezawa.hiroyu@jp.fujitsu.com>
>>> CC: David S. Miller<davem@davemloft.net>
>>> CC: Eric Dumazet<eric.dumazet@gmail.com>
>>> CC: Stephen Rothwell<sfr@canb.auug.org.au>
>>
>> Could you remake the patch onto the 'latest' linux-next ?
>> As Dave mentioned, some bandaids are already applied and this patch hunks.
>
> Applied patches by hand and did small test for hours.
> seems good.
>
> Reviewed-by: KAMEZAWA Hiroyuki<kamezawa.hiroyu@jp.fujitsu.com>
>
Kame,

Thanks. But see Dave's answer to this: He'd like me to follow a slightly 
different approach (I've attached a patch earlier)