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From:   Suren Baghdasaryan <surenb@google.com>
Date:   Wed, 11 Jan 2023 09:04:41 -0800
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Subject: Re: [PATCH 08/41] mm: introduce CONFIG_PER_VMA_LOCK
To:     Michal Hocko <mhocko@suse.com>
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On Wed, Jan 11, 2023 at 8:44 AM Michal Hocko <mhocko@suse.com> wrote:
>
> On Wed 11-01-23 08:28:49, Suren Baghdasaryan wrote:
> [...]
> > Anyhow. Sounds like the overhead of the current design is small enough
> > to remove CONFIG_PER_VMA_LOCK and let it depend only on architecture
> > support?
>
> Yes. Further optimizations can be done on top. Let's not over optimize
> at this stage.

Sure, I won't optimize any further.
Just to expand on your question. Original design would be problematic
for embedded systems like Android. It notoriously has a high number of
VMAs due to anonymous VMAs being named, which prevents them from
merging. 2M per process increase would raise questions, therefore I
felt the need for optimizing the memory overhead which is done in the
last patch.
Thanks for the feedback!

> --
> Michal Hocko
> SUSE Labs