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From:   Alistair Popple <apopple@nvidia.com>
To:     Tejun Heo <tj@kernel.org>
Cc:     Waiman Long <longman@redhat.com>,
        Yosry Ahmed <yosryahmed@google.com>, linux-mm@kvack.org,
        cgroups@vger.kernel.org, linux-kernel@vger.kernel.org,
        jgg@nvidia.com, jhubbard@nvidia.com, tjmercier@google.com,
        hannes@cmpxchg.org, surenb@google.com, mkoutny@suse.com,
        daniel@ffwll.ch, "Daniel P . Berrange" <berrange@redhat.com>,
        Alex Williamson <alex.williamson@redhat.com>,
        Zefan Li <lizefan.x@bytedance.com>,
        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH 14/19] mm: Introduce a cgroup for pinned memory
Date:   Tue, 07 Feb 2023 12:50:24 +1100
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Tejun Heo <tj@kernel.org> writes:

> On Mon, Feb 06, 2023 at 08:00:54PM -0500, Waiman Long wrote:
>> If it should not be part of the memcg, does it make sense to make it a
>> resource in the existing misc controller? I believe we don't want a
>> proliferation of new cgroup controllers.
>
> Yeah, if it's gonna be an independent knob, I suppose so, but I really think
> the locked accounting should be tied to the page, which mostly likely would
> mean that it'd be tied to the page ownership too making its natural place
> memcg.

Yes, I think it might be possible. I looked briefly at doing it when
initially developing the series but I would like to resolve the question
of independent knob vs. memcg before heading too far down either path.

> Thanks.