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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: DA70B100007 X-Stat-Signature: 16h1cht8yas93wtxt5m349mhhhhnqnd1 X-Rspam-User: X-Rspamd-Server: rspam06 X-HE-Tag: 1756456971-261429 X-HE-Meta: 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 LXBXCcMA E7ThIUczJgW+/u83agaETFQrmKXM9LD/FP8Uk4kgMRPHK4zk0zu/aKvQ0K1namXntrZFgcT7rqg3mvICUhwVKnitOVRsuy0WAzZp3bGzEtvo5uAt94lSIYtXJDaNO/zIxf25ZgnbZbxJJewfAs2k6I/ZauDbikBH3EWsb7F/LMRXXMzkq8vlOVAkx54B3n0d9g7zoDccwDSBwQEHSDGmBAu9bxGxH5SraZGwjAK1urgG+Vqp/+IFk7x5Isc4FQ780RWoRi2QHVe9/2E7cWyq7BJPyNeZ4q8gBjbhZUJgjzcW1F/HLBWo6sxX4/96YSl0x1lHx56xyb2gFfRvcxevsztZWOFjcfkikk2UyuDO5dTo2/608smVl1aqedjQfZTXVGhgNGvlQFTDiyOoSGsD8JZbNkstsOX8fYrC3ga2N2CZyABLcbiYghVLMH+9oJbTHBShCE6SrDK22hUx9Qavt0HmUdinCWgbDrrFV X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: >> >> I do wonder if we can identify this case and handle things differently. >> >> Perhaps even saying 'try and get the rmap lock, but if there's "too much" >> contention, grab the folio lock. > > Can you please elaborate what you mean? Where do you mean we can > possibly do something like this? > > UFFD move only works on PageAnonExclusive folios. So, would it help > (in terms of avoiding contention) if we were to change the condition: I think we shouldn't be using PAE here. Once could consider using folio_maybe_mapped_shared(), and assume contention on the folio lock if it is maybe mapped shared. But the real question is with whom we would be contending for the folio lock. Is it really other processes mapping that folio? I'm not so sure. -- Cheers David / dhildenb