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charset="us-ascii" X-Rspamd-Queue-Id: 68C761C0010 X-Rspamd-Server: rspam10 X-Rspam-User: X-Stat-Signature: ghd3cb6ay4y6tn53ubznc8dqjupc8gns X-HE-Tag: 1718135392-939872 X-HE-Meta: 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 Nad8MBJx 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000076, 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, Jun 11, 2024, Oliver Upton wrote: > On Tue, Jun 11, 2024 at 09:49:59AM -0700, James Houghton wrote: > > I think consolidating the callbacks is cleanest, like you had it in > > v2. I really wasn't sure about this change honestly, but it was my > > attempt to incorporate feedback like this[3] from v4. I'll consolidate > > the callbacks like you had in v2. > > My strong preference is to have the callers expectations of the > secondary MMU be explicit. Having ->${BLAH}_fast_only() makes this > abundantly clear both at the callsite and in the implementation. Partially agreed. We don't need a dedicated mmu_notifier API to achieve that for the callsites, e.g. ptep_clear_young_notify() passes fast_only=false, and a new ptep_clear_young_notify_fast_only() does the obvious. On the back end, odds are very good KVM is going to squish the "fast" and "slow" paths back into a common helper, so IMO having dedicated fast_only() APIs for the mmu_notifier hooks doesn't add much value in the end. I'm not opposed to dedicated hooks, but I after poking around a bit, I suspect that passing a fast_only flag will end up being less cleaner for all parties.