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charset=us-ascii Content-Disposition: inline In-Reply-To: <089f689d-f8dd-48ba-b6b0-6f91aa3b86f1@arm.com> X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: BA3C7A0025 X-Stat-Signature: c6f9wr87k3nxs15orc9684x3e5669xy4 X-Rspam-User: X-HE-Tag: 1709573865-258562 X-HE-Meta: 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 ScPx6zHO OrcFiOWI+xATY36twhcrOPgTDkTQUz96XFhWDKu7MSIVu4yzIuOLmLHVk8SiEupQ2NJdLd/eLBIoy/CpHF6NdVzR5Z77/vbepzhOYBDT3sDoazvmA/OlE244bhGIJdLlypS5DoJ9ggbQUv1JC21sgZy6l+9cHK24OnIvSN6j0dSv7KbCzq74nWdM+P/o8vfTRwMumbORwEDAdtLl6kH7w2I3tTsqlF4gJG0srhn37JfnzImv/MWNqmeGwzrZint6k9GsR9xJZn7V9GS2sXpJNHjybO6n34Ughcy2UAK2MEdphNyrqUr9gxQR9BOpSPDCU/gj1QUY/zfLCDzscBrH+WzpildPk5bpIi1ZRY3Tq2rTX0RsVQaFbtll+nTkjAP2an1k6Dy6g1gx4pOj62vtKFoGQH8fapjI9jsgECnpAZ5dGI1HYHAEpXNtvznar21C3bcmNCrqi4jDxbyBdIunk/xxgv/hZ8eGjUfua 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: On Mon, Mar 04, 2024 at 12:54:23PM +0000, Ryan Roberts wrote: > On 01/03/2024 18:47, Catalin Marinas wrote: > > On Mon, Feb 26, 2024 at 12:03:21PM +0000, Ryan Roberts wrote: > >> Make clear the atmicity/consistency requirements of the API and how we > >> achieve them. > >> > >> Link: https://lore.kernel.org/linux-mm/Zc-Tqqfksho3BHmU@arm.com/ > >> Signed-off-by: Ryan Roberts > >> --- > >> arch/arm64/mm/contpte.c | 24 ++++++++++++++---------- > >> 1 file changed, 14 insertions(+), 10 deletions(-) [...] > > Throughout the callers of this function, I couldn't find one where it > > matters. So I concluded that they don't need the dirty state. Normally > > the dirty state is passed to the page flags, so not lost after the pte > > has been cleaned. > > I agree we can simplify the semantics. But I think its better done in a separate > series (which I previously linked). > > What's the bottom line here? Are you ok with this comment as a short term > solution for now, or do you want something more radical (i.e. push to get the > series that does these simplifications reviewed and in time for v6.9). > > I still believe the current ptep_get_lockless() implementation is correct. So > given I have a plan to simplify in the long run, I hope we can still get this > series into v6.9 as planned. Yes, I'm fine with this patch. Assuming Andrew picked them up: Reviewed-by: Catalin Marinas I'd like to get the simplification in as well at some point as I think our ptep_get_lockless() is unnecessarily complex for most use-cases. -- Catalin