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AHgh+RqEljeaDOD+bQ9E0WA7XHKe7byQD+yZ+BKdRua4oR7+0Tp9ZgfMe1gbyQKQ/fAw6rbI83TYGTxQbQ==@kvack.org X-Gm-Message-State: AOJu0Yx3J0Yx8/z3fbPNPOnV8x2s3vNVnDl+uoBkaNScrwvA75hC6a3e FWHvzbaTNDefSzPIShxtqrPOdTVIsTW2rQvii+gXUkqNXqmxC7Qytfw+UTmuW02phny2R/ahKN3 cHnATVw== X-Received: from pfbkq9.prod.google.com ([2002:a05:6a00:4b09:b0:848:8808:ae6b]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a00:3d12:b0:842:708f:39be with SMTP id d2e1a72fcca58-84f2dff7a22mr1642518b3a.5.1785879346115; Tue, 04 Aug 2026 14:35:46 -0700 (PDT) Date: Tue, 4 Aug 2026 14:35:45 -0700 In-Reply-To: Mime-Version: 1.0 References: <4460e252-b6de-4df3-bea8-0368a9d0f4ff@kernel.org> <60552bee-3326-4917-b00f-5fb7ba3b8adb@kernel.org> <99037993-ee13-4160-8c87-b6642faea554@kernel.org> Message-ID: Subject: Re: [PATCH v9 14/41] mm: swap: Introduce lru_add_drain_progressive() From: Sean Christopherson To: Ackerley Tng Cc: "David Hildenbrand (Arm)" , aik@amd.com, andrew.jones@linux.dev, binbin.wu@linux.intel.com, brauner@kernel.org, chao.p.peng@linux.intel.com, jmattson@google.com, jthoughton@google.com, michael.roth@amd.com, oupton@kernel.org, pankaj.gupta@amd.com, qperret@google.com, rick.p.edgecombe@intel.com, rientjes@google.com, shivankg@amd.com, steven.price@arm.com, tabba@google.com, willy@infradead.org, wyihan@google.com, yan.y.zhao@intel.com, forkloop@google.com, pratyush@kernel.org, suzuki.poulose@arm.com, aneesh.kumar@kernel.org, liam@infradead.org, Paolo Bonzini , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Steven Rostedt , Masami Hiramatsu , Mathieu Desnoyers , Jonathan Corbet , Shuah Khan , Shuah Khan , Vishal Annapurve , Andrew Morton , Chris Li , Kairui Song , Kemeng Shi , Nhat Pham , Barry Song , Axel Rasmussen , Yuanchu Xie , Wei Xu , Youngjun Park , Qi Zheng , Shakeel Butt , Kiryl Shutsemau , Baoquan He , Jason Gunthorpe , John Hubbard , Peter Xu , Vlastimil Babka , "hughd@google.com" , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org, linux-coco@lists.linux.dev Content-Type: text/plain; charset="us-ascii" X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: AFEF040009 X-Stat-Signature: 1ompg9gemo4d5b5hgimk1edorc6oah4u X-Rspam-User: X-HE-Tag: 1785879347-199711 X-HE-Meta: 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 0+7nagX4 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Tue, Aug 04, 2026, Ackerley Tng wrote: > "David Hildenbrand (Arm)" writes: > > Andrew wants to give it some more time in -next, so I'm expecting it to > > land for 7.3. > > > >> 7.2 or 7.3, then I would strongly prefer to base v10 on linux-next (where > >> the fix will presumably land soonish), and target 7.4 for in-place > >> conversion. Then v10 can be applied against an early 7.3-rcN and we don't > >> need to juggle branches (assuming Andrew is ok taking the proposed patch > >> through the KVM tree). > > > > Agreed. We'd also have to get the actual preparation patch into 7.3. I can > > send it out and coordinate with Andrew. > > > > Thank you! > > When we were discussing this earlier at guest_memfd biweekly, before > deciding to refactor out a function like lru_cache_drain_for_folio(), we > did say that the likelihood of actually draining in practice is low, > especially on a machine with heavy load making allocations all the time. > > I think the threads with Xiaoyao have resolved, I can put v10 out > tomorrow. Would it be okay to go with the following from v8, and then > clean up later when lru_cache_drain_for_folio() is available? No. > I'm hoping not to push this back by a full cycle to 7.4, Sorry, but we've missed 7.3, irrespective of the lru_cache_drain_for_folio() fix. Even if v10 is perfect, applying tomorrow means it will get ~3 business days in linux-next before I send pull requests to Paolo. That's just not enough soak time for land a 40+ patch series, even if half of those patches are selftests. > and also hold back other series dependent on this one. Eh, I don't think there will be meaningful impact in practice. If v10 is good to go, I'll get it applied on 7.3-r1, and will also get an early pull request over to Paolo (probably around 7.3-rc4). I.e. folks can start posting against the landed series shortly after rc1, and I'll have a set-in-stone base on which to apply more stuff around rc4/rc5. And if v10 has issues, then *not* rushing it into 7.3 will likely be the fastest path forward.