Date: Thu, 24 Aug 2017 08:02:22 -0700
From: Tejun Heo <tj@kernel.org>
To: Waiman Long <longman@redhat.com>
Cc: Li Zefan <lizefan@huawei.com>, Johannes Weiner <hannes@cmpxchg.org>,
        cgroups@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] cpuset: Allow cpuset controller in default hierarchy
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Hello,

On Thu, Aug 24, 2017 at 10:56:21AM -0400, Waiman Long wrote:
> The main reason for sending out this patch is to figure out what exactly
> is in your mind before enabling cpuset in v2.
> 
> From my point of view, the exclusive setting makes cpuset behave more
> like a resource domain that a resource allocated to one cgroup won't be
> available for another cgroup. So we can argue it both ways whether it
> violates the basic hierarchy rules or not.

It's not even siblings interfering with other siblings.  The resource
knobs belong to the parent, right?  So, the only thing it's doing is
restricting the parent itself from creating certain configurations,
which can be argued to be a feature but it's a really weird policy
enforcement implemented in kernel.

> I will be in the Plumbers Conference next month and we can talk more
> about this. My goal is to make cgroup v2 ready for prime time hopefully
> by the end of the year.

Sure, the only thing I think we need for cpuset is cutting down the
interface to the minimal set which provides all the features to
userspace.

Thanks.

-- 
tejun