From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matt Helsley Subject: Re: [PATCH 1/4] cgroup freezer: Fix buggy resume test for tasks frozen with cgroup freezer Date: Thu, 11 Jun 2009 14:56:03 -0700 Message-ID: <20090611215603.GE6739@us.ibm.com> References: <91260d5797bcf233ca54c7b41da8278e99b4ca66.1244019829.git.matthltc@us.ibm.com> <20090603160551.GB7848@us.ibm.com> <4A271B75.7090607@cn.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <4A271B75.7090607-BthXqXjhjHXQFUHtdCDX3A@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Li Zefan Cc: Containers , "Rafael J. Wysocki" , Pavel Machek , Paul Menage , linux-pm-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org List-Id: containers.vger.kernel.org On Thu, Jun 04, 2009 at 08:55:17AM +0800, Li Zefan wrote: > Serge E. Hallyn wrote: > > Quoting Matt Helsley (matthltc-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org): > >> -int cgroup_frozen(struct task_struct *task) > >> +int cgroup_freezing_or_frozen(struct task_struct *task) > >> { > >> struct freezer *freezer; > >> enum freezer_state state; > >> > >> task_lock(task); > >> freezer = task_freezer(task); > >> - state = freezer->state; > >> + if (!freezer->css.cgroup->parent) > >> + state = CGROUP_THAWED; /* root cgroup can't be frozen */ > >> + else > >> + state = freezer->state; > > > > Why do you have to add this special-casing now? I thought > > we were already preventing freezing the root cgroup, so > > freezer->state should be sane in that case anyway? > > > > Yeah, IIRC top_freezer->state is alwasy CGROUP_THAWED, so this > check is redundant. Right, fixed. Cheers, -Matt