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charset=us-ascii Content-Disposition: inline In-Reply-To: <874j98gjfg.fsf@nvdebian.thelocal> User-Agent: Mutt/1.5.17 (2007-11-01) X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: E415440016 X-Stat-Signature: x1n77k1u4erdgpg7pcp7xgdhfet9jx9e X-Rspam-User: X-HE-Tag: 1719921116-324494 X-HE-Meta: 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 7VlKGFTd wxx13zsXTzBd9kS+QnaIWjf57cLT1Ch7Q3Yu1zRSg/ZqgWBEBi3VRxSYfLI89DlrcT3r02v4B3uebUq9vUHOutuSlYbemSicArBLt5dY4GE7gvaqAfgjQ/BngfQ== 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 Tue, Jul 02, 2024 at 08:19:01PM +1000, Alistair Popple wrote: > > (B) As long as we have subpage mapcounts, this prevents vmemmap > > optimizations [1]. Is that only used for device-dax for now and are > > there no plans to make use of that for fs-dax? > > I don't have any plans to. This is purely focussed on refcounting pages > "like normal" so we can get rid of all the DAX special casing. > > > (C) We managed without so far :) > > Indeed, although Christoph has asked repeatedly ([1], [2] and likely > others) that this gets fixed and I finally got sick of it coming up > everytime I need to touch something with ZONE_DEVICE pages :) > > Also it removes the need for people to understand the special DAX page > recounting scheme and ends up removing a bunch of cruft as a bonus: > > 59 files changed, 485 insertions(+), 869 deletions(-) > > And that's before I clean up all the pgmap reference handling. It also > removes the pXX_trans_huge and pXX_leaf distinction. So we managed, but > things could be better IMHO. Yes. I can't wait for this series making the finish line. There might be more chance for cleanups and optimizations around ZONE_DEVICE, but this alone is a huge step forward.