Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756112AbYJUVkg (ORCPT ); Tue, 21 Oct 2008 17:40:36 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751380AbYJUVk2 (ORCPT ); Tue, 21 Oct 2008 17:40:28 -0400 Received: from e36.co.us.ibm.com ([32.97.110.154]:39423 "EHLO e36.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751508AbYJUVk1 (ORCPT ); Tue, 21 Oct 2008 17:40:27 -0400 Subject: Re: [PATCH 2/4] freezer_cg: remove redundant check in freezer_can_attach() From: Matt Helsley To: Li Zefan Cc: Andrew Morton , Cedric Le Goater , LKML , Linux Containers In-Reply-To: <48FD273F.3040505@cn.fujitsu.com> References: <48FD26F5.1070809@cn.fujitsu.com> <48FD273F.3040505@cn.fujitsu.com> Content-Type: text/plain Date: Tue, 21 Oct 2008 14:40:33 -0700 Message-Id: <1224625233.2991.87.camel@enoch> Mime-Version: 1.0 X-Mailer: Evolution 2.22.3.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1712 Lines: 54 On Tue, 2008-10-21 at 08:50 +0800, Li Zefan wrote: > It is sufficient to check if @task is frozen, and no need to check if > the original freezer is frozen. Looks great! Thanks! Acked-by: Matt Helsley > Signed-off-by: Li Zefan > --- > kernel/cgroup_freezer.c | 16 +++++++--------- > 1 files changed, 7 insertions(+), 9 deletions(-) > > diff --git a/kernel/cgroup_freezer.c b/kernel/cgroup_freezer.c > index 7f54d1c..6fadafe 100644 > --- a/kernel/cgroup_freezer.c > +++ b/kernel/cgroup_freezer.c > @@ -162,9 +162,13 @@ static int freezer_can_attach(struct cgroup_subsys *ss, > struct task_struct *task) > { > struct freezer *freezer; > - int retval; > > - /* Anything frozen can't move or be moved to/from */ > + /* > + * Anything frozen can't move or be moved to/from. > + * > + * Since orig_freezer->state == FROZEN means that @task has been > + * frozen, so it's sufficient to check the latter condition. > + */ > > if (is_task_frozen_enough(task)) > return -EBUSY; > @@ -173,13 +177,7 @@ static int freezer_can_attach(struct cgroup_subsys *ss, > if (freezer->state == CGROUP_FROZEN) > return -EBUSY; > > - retval = 0; > - task_lock(task); > - freezer = task_freezer(task); > - if (freezer->state == CGROUP_FROZEN) > - retval = -EBUSY; > - task_unlock(task); > - return retval; > + return 0; > } > > static void freezer_fork(struct cgroup_subsys *ss, struct task_struct *task) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/