Sender: Tejun Heo <htejun@gmail.com>
Date:   Mon, 6 Feb 2023 12:36:25 -1000
From:   Tejun Heo <tj@kernel.org>
To:     Yosry Ahmed <yosryahmed@google.com>
Cc:     Alistair Popple <apopple@nvidia.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
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On Mon, Feb 06, 2023 at 02:32:10PM -0800, Yosry Ahmed wrote:
> I guess it boils down to which we want:
> (a) Limit the amount of memory processes in a cgroup can be pinned/locked.
> (b) Limit the amount of memory charged to a cgroup that can be pinned/locked.
> 
> The proposal is doing (a), I suppose if this was part of memcg it
> would be (b), right?
> 
> I am not saying it should be one or the other, I am just making sure
> my understanding is clear.

I don't quite understand what the distinction would mean in practice. It's
just odd to put locked memory in a separate controller from interface POV.

Thanks.

-- 
tejun