From mboxrd@z Thu Jan 1 00:00:00 1970 From: Li Zefan Subject: Re: [PATCH] memcg: don't do cleanup manually if mem_cgroup_css_online() fails Date: Tue, 2 Apr 2013 16:03:57 +0800 Message-ID: <515A90ED.7010208@huawei.com> References: <515A8A40.6020406@huawei.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <515A8A40.6020406@huawei.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii" To: Michal Hocko Cc: Glauber Costa , Johannes Weiner , KAMEZAWA Hiroyuki , LKML , Cgroups , linux-mm@kvack.org On 2013/4/2 15:35, Li Zefan wrote: > If memcg_init_kmem() returns -errno when a memcg is being created, > mem_cgroup_css_online() will decrement memcg and its parent's refcnt, > (but strangely there's no mem_cgroup_put() for mem_cgroup_get() called > in memcg_propagate_kmem()). The comment in memcg_propagate_kmem() suggests it knows mem_cgroup_css_free() will be called in failure, while mem_cgroup_css_online() doesn't know. > > But then cgroup core will call mem_cgroup_css_free() to do cleanup... > > Signed-off-by: Li Zefan > --- > mm/memcontrol.c | 11 +---------- > 1 file changed, 1 insertion(+), 10 deletions(-) From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx193.postini.com [74.125.245.193]) by kanga.kvack.org (Postfix) with SMTP id 58C816B0027 for ; Tue, 2 Apr 2013 04:04:31 -0400 (EDT) Message-ID: <515A90ED.7010208@huawei.com> Date: Tue, 2 Apr 2013 16:03:57 +0800 From: Li Zefan MIME-Version: 1.0 Subject: Re: [PATCH] memcg: don't do cleanup manually if mem_cgroup_css_online() fails References: <515A8A40.6020406@huawei.com> In-Reply-To: <515A8A40.6020406@huawei.com> Content-Type: text/plain; charset="GB2312" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko Cc: Glauber Costa , Johannes Weiner , KAMEZAWA Hiroyuki , LKML , Cgroups , linux-mm@kvack.org On 2013/4/2 15:35, Li Zefan wrote: > If memcg_init_kmem() returns -errno when a memcg is being created, > mem_cgroup_css_online() will decrement memcg and its parent's refcnt, > (but strangely there's no mem_cgroup_put() for mem_cgroup_get() called > in memcg_propagate_kmem()). The comment in memcg_propagate_kmem() suggests it knows mem_cgroup_css_free() will be called in failure, while mem_cgroup_css_online() doesn't know. > > But then cgroup core will call mem_cgroup_css_free() to do cleanup... > > Signed-off-by: Li Zefan > --- > mm/memcontrol.c | 11 +---------- > 1 file changed, 1 insertion(+), 10 deletions(-) -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760692Ab3DBIEa (ORCPT ); Tue, 2 Apr 2013 04:04:30 -0400 Received: from szxga01-in.huawei.com ([119.145.14.64]:54567 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759509Ab3DBIEX (ORCPT ); Tue, 2 Apr 2013 04:04:23 -0400 Message-ID: <515A90ED.7010208@huawei.com> Date: Tue, 2 Apr 2013 16:03:57 +0800 From: Li Zefan User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:17.0) Gecko/20130307 Thunderbird/17.0.4 MIME-Version: 1.0 To: Michal Hocko CC: Glauber Costa , Johannes Weiner , KAMEZAWA Hiroyuki , LKML , Cgroups , Subject: Re: [PATCH] memcg: don't do cleanup manually if mem_cgroup_css_online() fails References: <515A8A40.6020406@huawei.com> In-Reply-To: <515A8A40.6020406@huawei.com> Content-Type: text/plain; charset="GB2312" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.135.68.215] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2013/4/2 15:35, Li Zefan wrote: > If memcg_init_kmem() returns -errno when a memcg is being created, > mem_cgroup_css_online() will decrement memcg and its parent's refcnt, > (but strangely there's no mem_cgroup_put() for mem_cgroup_get() called > in memcg_propagate_kmem()). The comment in memcg_propagate_kmem() suggests it knows mem_cgroup_css_free() will be called in failure, while mem_cgroup_css_online() doesn't know. > > But then cgroup core will call mem_cgroup_css_free() to do cleanup... > > Signed-off-by: Li Zefan > --- > mm/memcontrol.c | 11 +---------- > 1 file changed, 1 insertion(+), 10 deletions(-)