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Date:   Tue, 4 Apr 2023 16:23:36 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     Suren Baghdasaryan <surenb@google.com>
Cc:     linux-mm@kvack.org, linux-fsdevel@vger.kernel.org,
        Punit Agrawal <punit.agrawal@bytedance.com>
Subject: Re: [PATCH 6/6] mm: Run the fault-around code under the VMA lock
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On Tue, Apr 04, 2023 at 02:58:50PM +0100, Matthew Wilcox (Oracle) wrote:
> The map_pages fs method should be safe to run under the VMA lock instead
> of the mmap lock.  This should have a measurable reduction in contention
> on the mmap lock.

https://github.com/antonblanchard/will-it-scale/pull/37/files should
be a good microbenchmark to report numbers from.  Obviously real-world
benchmarks will be more compelling.