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charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspam-User: X-Rspamd-Queue-Id: 2D18940016 X-Rspamd-Server: rspam04 X-Stat-Signature: fpr47cssfwsf5kratbcge7pbisgcg9dd X-HE-Tag: 1765827765-481368 X-HE-Meta: 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 ZF3lrzmP pZtkJIrc5kw5FZYrBkUQmhzvrujf7p4Ge4yTYzMK+GWTREwKcWNfEjLdlEH92OQ1R4LkRjkYJb+phAPPFKYFXbf/ICxOKcTGrAMQoOWA5MLZDhdsZ9coZRo7Rk4JK7FbbrxeGy8BQSlD+NbOzPq1xdLOEPHAl8IvYEqmasTb6jDlkNc2caySP1h+NlF1efCFM3H6KvwbgGhzW0/6S9rP7fQjl/QW8C5hXxT+9FaEvUJH76vj02mpcarXkPyhvcf+IBOigNLgFpo/e7JAjpPvEV1jG//K4SN96LNqTxYtgUAyLl6fuejpz51A4o+Qd6uOmHOsotzubqGWJdLbYS5ED/6OY5EkQRHcgpv+ACBBf6/iK1/5xPzFyi89ycOdD3xaCC1yST5T+TmelCQaLZdF9tt2iage5HkhFtfE615qOcs30tt5bfHUXYJ/v3U+aw0Naksr64VCYSPvU4ji+6rMu4z9y8w== 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 Sun, Dec 14, 2025 at 10:52=E2=80=AFPM Deepanshu Kartikey wrote: > > On Mon, Dec 15, 2025 at 9:42=E2=80=AFAM Johannes Weiner wrote: > > > > Fixes: bd74fdaea146 ("mm: multi-gen LRU: support page table walks") > > > > That seems unrelated? > > Sorry for the wrong fixes. Correct Fixes: ee814fe23daf ("mm: vmscan: > clean up struct scan_control") > > I'll wait for input from someone with MGLRU context on the broader discus= sion. > This warning came from commit e9d4e1ee7880 ("mm: multi-gen LRU: clarify scan_control flags") [1]. The original rationale: > 4. sc->may_writepage and sc->may_unmap, which indicates opportunistic > reclaim, are rejected, since unmapped clean folios are already > prioritized. Scanning for more of them is likely futile and can > cause high reclaim latency when there is a large number of memcgs. As far as I can tell this was a sanity check to ensure `lru_gen_shrink_lruvec` avoids extra work for minimal gain. Perhaps this shouldn't be a warning? Always setting may_writepage in this case would free more folios. I'm not against removing the warning either. @Wei Xu @Axel Rasmussen Any opinions? [1] https://lore.kernel.org/all/20221222041905.2431096-8-yuzhao@google.com/= T/#u