From: Tejun Heo <tj@kernel.org>
To: Waiman Long <longman@redhat.com>
Cc: "Michal Koutný" <mkoutny@suse.com>,
"Zefan Li" <lizefan.x@bytedance.com>,
"Johannes Weiner" <hannes@cmpxchg.org>,
"Jonathan Corbet" <corbet@lwn.net>,
"Shuah Khan" <shuah@kernel.org>,
cgroups@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org,
"Andrew Morton" <akpm@linux-foundation.org>,
"Roman Gushchin" <guro@fb.com>, "Phil Auld" <pauld@redhat.com>,
"Peter Zijlstra" <peterz@infradead.org>,
"Juri Lelli" <juri.lelli@redhat.com>,
"Frederic Weisbecker" <frederic@kernel.org>,
"Marcelo Tosatti" <mtosatti@redhat.com>
Subject: Re: [PATCH v11 3/8] cgroup/cpuset: Allow no-task partition to have empty cpuset.cpus.effective
Date: Mon, 13 Jun 2022 07:23:03 -1000 [thread overview]
Message-ID: <Yqdydz3vNgfVMgDf@slm.duckdns.org> (raw)
In-Reply-To: <f1c33447-1f82-9698-6b0c-fc9ffb12b4bb@redhat.com>
Hello,
On Mon, Jun 13, 2022 at 12:47:37PM -0400, Waiman Long wrote:
> On 6/13/22 10:02, Michal Koutný wrote:
> > On Sun, Jun 12, 2022 at 04:55:13PM -1000, Tejun Heo <tj@kernel.org> wrote:
> > > But how would that happen? A lot of other things would break too if that
> > > were to happen.
> > cpuset is a threaded controller where the internal-node-constraint does
> > not hold. So the additional condition for cpuset migrations is IMO
> > warranted (and needed if there's no "fall up").
>
> Yes, you are right. cpuset is threaded and so it may have tasks even if it
> is not the leaf node.
And we had this same exchange the last time. Can you please add a comment?
We might also already have had this exchange before too but is it necessary
to allow threaded cgroups to be isolated roots? The interaction between
being threaded and isolated is cleaner at that layer as it's interactions
between two explicit mode changes.
Thanks.
--
tejun
next prev parent reply other threads:[~2022-06-13 19:21 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-05-10 15:34 [PATCH v11 0/8] cgroup/cpuset: cpu partition code enhancements Waiman Long
2022-05-10 15:34 ` [PATCH v11 1/8] cgroup/cpuset: Add top_cpuset check in update_tasks_cpumask() Waiman Long
2022-05-10 15:34 ` [PATCH v11 2/8] cgroup/cpuset: Miscellaneous cleanups & add helper functions Waiman Long
2022-05-10 15:34 ` [PATCH v11 3/8] cgroup/cpuset: Allow no-task partition to have empty cpuset.cpus.effective Waiman Long
2022-06-12 17:40 ` Tejun Heo
2022-06-12 17:41 ` Tejun Heo
2022-06-13 2:53 ` Waiman Long
2022-06-13 2:55 ` Tejun Heo
2022-06-13 3:04 ` Waiman Long
2022-06-13 14:02 ` Michal Koutný
2022-06-13 16:47 ` Waiman Long
2022-06-13 17:23 ` Tejun Heo [this message]
2022-06-13 2:50 ` Waiman Long
2022-05-10 15:34 ` [PATCH v11 4/8] cgroup/cpuset: Relax constraints to partition & cpus changes Waiman Long
2022-05-10 15:34 ` [PATCH v11 5/8] cgroup/cpuset: Add a new isolated cpus.partition type Waiman Long
2022-05-10 15:34 ` [PATCH v11 6/8] cgroup/cpuset: Show invalid partition reason string Waiman Long
2022-05-10 15:34 ` [PATCH v11 7/8] cgroup/cpuset: Update description of cpuset.cpus.partition in cgroup-v2.rst Waiman Long
2022-06-12 17:49 ` Tejun Heo
2022-06-13 3:02 ` Waiman Long
2022-06-13 3:12 ` Tejun Heo
2022-06-13 13:18 ` Waiman Long
2022-06-13 17:06 ` Waiman Long
2022-06-13 14:24 ` Michal Koutný
2022-06-13 17:28 ` Tejun Heo
2022-06-13 17:55 ` Michal Koutný
2022-06-13 18:00 ` Tejun Heo
2022-06-14 11:53 ` Michal Koutný
2022-06-27 19:10 ` Tejun Heo
2022-06-30 14:32 ` Michal Koutný
2022-06-30 22:53 ` Tejun Heo
2022-05-10 15:34 ` [PATCH v11 8/8] kselftest/cgroup: Add cpuset v2 partition root state test Waiman Long
2022-05-21 10:24 ` Muhammad Usama Anjum
2022-05-22 2:40 ` Waiman Long
2022-05-20 16:00 ` [PATCH v11 0/8] cgroup/cpuset: cpu partition code enhancements Sebastian Andrzej Siewior
2022-05-20 16:46 ` Waiman Long
2022-05-24 16:48 ` Sebastian Andrzej Siewior
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