From mboxrd@z Thu Jan  1 00:00:00 1970
From: Waiman Long <longman@redhat.com>
Subject: Re: [RFC PATCH 0/5] cgroup/cpuset: A new "isolcpus" paritition
Date: Wed, 12 Apr 2023 20:26:03 -0400
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To: Tejun Heo <tj@kernel.org>
Cc: Zefan Li <lizefan.x@bytedance.com>, Johannes Weiner <hannes@cmpxchg.org>, Jonathan Corbet <corbet@lwn.net>, Shuah Khan <shuah@kernel.org>, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, Juri Lelli <juri.lelli@redhat.com>, Valentin Schneider <vschneid@redhat.com>, Frederic Weisbecker <frederic@kernel.org>


On 4/12/23 20:03, Tejun Heo wrote:
> Hello,
>
> On Wed, Apr 12, 2023 at 04:33:29PM -0400, Waiman Long wrote:
>> I think we can. You mean having a new "cpuset.cpus.isolated" cgroupfs fi=
le.
>> So there will be one in the root cgroup that defines all the isolated CP=
Us
>> one can have. It is then distributed down the hierarchy and can be claim=
ed
>> only if a cgroup becomes an "isolated" partition. There will be a slight
> Yeah, that seems a lot more congruent with the typical pattern.
>
>> change in the semantics of an "isolated" partition, but I doubt there wi=
ll
>> be much users out there.
> I haven't thought through it too hard but what prevents staying compatible
> with the current behavior?

It is possible to stay compatible with existing behavior. It is just=20
that a break from existing behavior will make the solution more clean.

So the new behavior will be:

 =C2=A0 If the "cpuset.cpus.isolated" isn't set, the existing rules applies=
.=20
If it is set, the new rule will be used.

Does that look reasonable to you?

Cheers,
Longman