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From:   Yu Zhao <yuzhao@google.com>
Date:   Wed, 2 Aug 2023 11:02:40 -0600
Message-ID: <CAOUHufZr8ym0kzoa99=k3Gquc4AdoYXMaj-kv99u5FPv1KkezA@mail.gmail.com>
Subject: Re: [PATCH v4 0/3] Optimize large folio interaction with deferred split
To:     Ryan Roberts <ryan.roberts@arm.com>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Matthew Wilcox <willy@infradead.org>,
        Yin Fengwei <fengwei.yin@intel.com>,
        David Hildenbrand <david@redhat.com>,
        Yang Shi <shy828301@gmail.com>,
        "Huang, Ying" <ying.huang@intel.com>, Zi Yan <ziy@nvidia.com>,
        Nathan Chancellor <nathan@kernel.org>,
        Alexander Gordeev <agordeev@linux.ibm.com>,
        Gerald Schaefer <gerald.schaefer@linux.ibm.com>,
        "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org
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On Wed, Aug 2, 2023 at 10:42=E2=80=AFAM Ryan Roberts <ryan.roberts@arm.com>=
 wrote:
>
> Hi Andrew,
>
> After discussion about this in Matthew's THP Cabal, we have decided to ta=
ke a
> different approach with this patch set. Could you therefore remove it fro=
m
> mm-unstable, please? Sorry about the noise.
>
> I'm going to try 2 different approaches:
>  - avoid the split lock contention by using mmu gather (suggested by Kiri=
ll)
>  - expand the zap pte batching to also cover file folios (as requested by=
 Yu).

Also we didn't have the chance to clarify before Ryan dropped out from
the meeting: I don't think this series is a prerequisite for the other
series ("variable-order, large folios for anonymous memory") at all.
They can move along in parallel: one is specific for anon and the
other (this series) is generic for all types of large folios.