From: Peter Zijlstra <peterz@infradead.org>
To: Tejun Heo <tj@kernel.org>
Cc: Li Zefan <lizefan@huawei.com>,
Glauber Costa <glommer@parallels.com>,
containers@lists.linux-foundation.org, cgroups@vger.kernel.org,
linux-kernel@vger.kernel.org, Michal Hocko <mhocko@suse.cz>,
Paul Turner <pjt@google.com>,
Johannes Weiner <hannes@cmpxchg.org>, Thomas Graf <tgraf@suug.ch>,
"Serge E. Hallyn" <serue@us.ibm.com>,
Paul Mackerras <paulus@samba.org>, Ingo Molnar <mingo@redhat.com>,
Arnaldo Carvalho de Melo <acme@ghostprotocols.net>,
Neil Horman <nhorman@tuxdriver.com>,
"Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>,
"Daniel P. Berrange" <berrange@redhat.com>,
Lennart Poettering <lennart@poettering.net>,
Kay Sievers <kay.sievers@vrfy.org>
Subject: Re: [RFC] cgroup TODOs
Date: Fri, 14 Sep 2012 20:23:41 +0200 [thread overview]
Message-ID: <1347647021.7172.74.camel@twins> (raw)
In-Reply-To: <20120914175944.GF17747@google.com>
On Fri, 2012-09-14 at 10:59 -0700, Tejun Heo wrote:
> Hello,
>
> On Fri, Sep 14, 2012 at 05:12:31PM +0800, Li Zefan wrote:
> > Agreed. The biggest issue in cpuset is if hotplug makes a cpuset's cpulist
> > empty the tasks in it will be moved to an ancestor cgroup, which requires
> > holding cgroup lock. We have to either change cpuset's behavior or eliminate
> > the global lock.
>
> Does that have to happen synchronously? Can't we have a cgroup
> operation which asynchronously pushes all tasks in a cgroup to its
> parent from a work item?
Its hotplug, all hotplug stuff is synchronous, the last thing hotplug
needs is the added complexity of async callbacks. Also pushing stuff out
into worklets just to work around locking issues is vile.
<handwave as I never can remember all the cgroup stuff/>
Can't we play games by pinning both cgroups with a reference and playing
games with threadgroup_change / task_lock for the individual tasks being
moved about?
next prev parent reply other threads:[~2012-09-14 18:24 UTC|newest]
Thread overview: 70+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-09-13 20:58 [RFC] cgroup TODOs Tejun Heo
2012-09-14 9:04 ` Mike Galbraith
2012-09-14 17:17 ` Tejun Heo
2012-09-14 9:10 ` Daniel P. Berrange
2012-09-14 13:58 ` Vivek Goyal
2012-09-14 19:29 ` Tejun Heo
2012-09-14 21:51 ` Kay Sievers
[not found] ` <5052E7DF.7040000@parallels.com>
2012-09-14 9:12 ` Li Zefan
2012-09-14 11:22 ` Peter Zijlstra
2012-09-14 17:59 ` Tejun Heo
2012-09-14 18:23 ` Peter Zijlstra [this message]
2012-09-14 18:33 ` Tejun Heo
2012-09-14 17:43 ` Tejun Heo
2012-09-17 8:50 ` Glauber Costa
2012-09-17 17:21 ` Tejun Heo
2012-09-14 11:15 ` Peter Zijlstra
2012-09-14 12:54 ` Daniel P. Berrange
2012-09-14 17:53 ` Tejun Heo
2012-09-14 14:25 ` Vivek Goyal
2012-09-14 14:53 ` Peter Zijlstra
2012-09-14 15:14 ` Vivek Goyal
2012-09-14 21:57 ` Tejun Heo
2012-09-17 15:27 ` Vivek Goyal
2012-09-18 18:08 ` Vivek Goyal
2012-09-14 21:39 ` Tejun Heo
2012-09-17 15:05 ` Vivek Goyal
2012-09-17 16:40 ` Tejun Heo
2012-09-14 15:03 ` Michal Hocko
2012-09-19 14:02 ` Michal Hocko
2012-09-19 14:03 ` [PATCH 2.6.32] memcg: warn on deeper hierarchies with use_hierarchy==0 Michal Hocko
2012-09-19 19:38 ` David Rientjes
2012-09-20 13:24 ` Michal Hocko
2012-09-20 22:33 ` David Rientjes
2012-09-21 7:16 ` Michal Hocko
2012-09-19 14:03 ` [PATCH 3.0] " Michal Hocko
2012-09-19 14:05 ` [PATCH 3.2+] " Michal Hocko
2012-09-14 18:07 ` [RFC] cgroup TODOs Vivek Goyal
2012-09-14 18:53 ` Tejun Heo
2012-09-14 19:28 ` Vivek Goyal
2012-09-14 19:44 ` Tejun Heo
2012-09-14 19:49 ` Tejun Heo
2012-09-14 20:39 ` Tejun Heo
2012-09-17 8:40 ` Glauber Costa
2012-09-17 17:30 ` Tejun Heo
2012-09-17 14:37 ` Vivek Goyal
2012-09-14 18:36 ` Aristeu Rozanski
2012-09-14 18:54 ` Tejun Heo
2012-09-15 2:20 ` Serge E. Hallyn
2012-09-15 9:27 ` Controlling devices and device namespaces Eric W. Biederman
2012-09-15 22:05 ` Serge E. Hallyn
2012-09-16 0:24 ` Eric W. Biederman
2012-09-16 3:31 ` Serge E. Hallyn
2012-09-16 11:21 ` Alan Cox
2012-09-16 11:56 ` Eric W. Biederman
2012-09-16 12:17 ` Eric W. Biederman
2012-09-16 13:32 ` Serge Hallyn
2012-09-16 14:23 ` Eric W. Biederman
2012-09-16 16:13 ` Alan Cox
2012-09-16 17:49 ` Eric W. Biederman
2012-09-16 16:15 ` Serge Hallyn
2012-09-16 16:53 ` Eric W. Biederman
2012-09-16 8:19 ` [RFC] cgroup TODOs James Bottomley
2012-09-16 14:41 ` Eric W. Biederman
2012-09-17 13:21 ` Aristeu Rozanski
2012-09-14 22:03 ` Dhaval Giani
2012-09-14 22:06 ` Tejun Heo
2012-09-20 1:33 ` Andy Lutomirski
2012-09-20 18:26 ` Tejun Heo
2012-09-20 18:39 ` Andy Lutomirski
2012-09-21 21:40 ` Tejun Heo
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