Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753330Ab1BBHXQ (ORCPT ); Wed, 2 Feb 2011 02:23:16 -0500 Received: from e3.ny.us.ibm.com ([32.97.182.143]:46299 "EHLO e3.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752841Ab1BBHXP (ORCPT ); Wed, 2 Feb 2011 02:23:15 -0500 Date: Tue, 1 Feb 2011 23:23:11 -0800 From: Matt Helsley To: Matt Helsley Cc: jacob.jun.pan@linux.intel.com, container cgroup , LKML , Paul Menage , Arjan van de Ven , "Kirill A. Shutsemov" Subject: Re: [PATCH] cgroups: respect cgroup timer slack value in prctl Message-ID: <20110202072311.GP16432@count0.beaverton.ibm.com> References: <1296600103-15726-1-git-send-email-jacob.jun.pan@linux.intel.com> <20110202070743.GO16432@count0.beaverton.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110202070743.GO16432@count0.beaverton.ibm.com> User-Agent: Mutt/1.5.20 (2009-06-14) X-Content-Scanned: Fidelis XPS MAILER Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4996 Lines: 146 On Tue, Feb 01, 2011 at 11:07:43PM -0800, Matt Helsley wrote: > On Tue, Feb 01, 2011 at 02:41:43PM -0800, jacob.jun.pan@linux.intel.com wrote: > > From: Jacob Pan > > > > Per cgroup timer slack value is used to manage task groups > > for more friendly power management behavior. Once a task is > > attached to a cgroup, we should not allow user to change > > (escape) the per cgroup restriction unless a more relaxed > > timer slack value is given by user via prctl. > > > > Signed-off-by: Jacob Pan > > > --- > > include/linux/cgroup.h | 13 +++++++++++++ > > Looks like the original two patches (one or more implementing: > > > kernel/cgroup_timer_slack.c | 4 ---- > > ) were not sent to containers@lists.linux-foundation.org ? Oops, I didn't see the patches from Kirill A. Shutsemov that this apparently applies to, sorry. Odd, my mail client doesn't show a Cc for him on this thread... (added) Cheers, -Matt > > > kernel/sys.c | 21 ++++++++++++++++++++- > > 3 files changed, 33 insertions(+), 5 deletions(-) > > > > diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h > > index ed4ba11..4405666 100644 > > --- a/include/linux/cgroup.h > > +++ b/include/linux/cgroup.h > > @@ -627,6 +627,19 @@ bool css_is_ancestor(struct cgroup_subsys_state *cg, > > unsigned short css_id(struct cgroup_subsys_state *css); > > unsigned short css_depth(struct cgroup_subsys_state *css); > > > > +#ifdef CONFIG_CGROUP_TIMER_SLACK > > +struct timer_slack_cgroup { > > + struct cgroup_subsys_state css; > > + unsigned long timer_slack_ns; > > +}; > > + > > +static inline struct timer_slack_cgroup *task_timer_slack(struct task_struct *task) > > +{ > > + return container_of(task_subsys_state(task, timer_slack_subsys_id), > > + struct timer_slack_cgroup, css); > > +} > > +#endif > > + > > #else /* !CONFIG_CGROUPS */ > > > > static inline int cgroup_init_early(void) { return 0; } > > diff --git a/kernel/cgroup_timer_slack.c b/kernel/cgroup_timer_slack.c > > index daa452d..1de122a 100644 > > --- a/kernel/cgroup_timer_slack.c > > +++ b/kernel/cgroup_timer_slack.c > > @@ -4,10 +4,6 @@ > > #include > > > > struct cgroup_subsys timer_slack_subsys; > > -struct timer_slack_cgroup { > > - struct cgroup_subsys_state css; > > - unsigned long timer_slack_ns; > > -}; > > > > static struct timer_slack_cgroup *cgroup_to_tslack_cgroup(struct cgroup *cgroup) > > { > > diff --git a/kernel/sys.c b/kernel/sys.c > > index 7f5a0cd..433fcdb 100644 > > --- a/kernel/sys.c > > +++ b/kernel/sys.c > > @@ -37,6 +37,8 @@ > > #include > > #include > > #include > > +#include > > +#include > > > > #include > > #include > > @@ -1688,8 +1690,25 @@ SYSCALL_DEFINE5(prctl, int, option, unsigned long, arg2, unsigned long, arg3, > > if (arg2 <= 0) > > current->timer_slack_ns = > > current->default_timer_slack_ns; > > - else > > + else { > > +#ifdef CONFIG_CGROUP_TIMER_SLACK > > + /* only allow more relaxed slack value than > > + * the attached timer slack cgroup allows. > > + */ > > + unsigned long cg_timer_slack; > > + > > + rcu_read_lock(); > > + cg_timer_slack = task_timer_slack(current)->timer_slack_ns; > > + rcu_read_unlock(); > > + if (cg_timer_slack < arg2 || cg_timer_slack > > + == TIMER_SLACK_NS_DEFAULT) > > + current->timer_slack_ns = arg2; > > + else > > + return -EINVAL; > > +#else > > Looks like this could be an inline function which returns the > minimum timer slack allowed for the task. Then the code here would be: > > if (arg2 <= 0) > current->timer_slack_ns = current->default_timer_slack_ns; > else { > if (arg2 < min_timer_slack_ns(tsk)) > return -EINVAL; /* Can't set less than the minimum */ > current->timer_slack_ns = arg2; > } > > and the #ifdef CONFIG_CGROUP_TIMER_SLACK bits could be in a header as > usual. > > Incidentally, shouldn't that really be -EPERM since it's not an invalid > value -- just one that's not permitted due to restrictions imposed by > the cgroup subsystem? > > > current->timer_slack_ns = arg2; > > +#endif > > + } > > error = 0; > > break; > > case PR_MCE_KILL: > > -- > > 1.7.0.4 > > > > _______________________________________________ > > Containers mailing list > > Containers@lists.linux-foundation.org > > https://lists.linux-foundation.org/mailman/listinfo/containers > _______________________________________________ > Containers mailing list > Containers@lists.linux-foundation.org > https://lists.linux-foundation.org/mailman/listinfo/containers -- 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/