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charset=us-ascii Content-Disposition: inline In-Reply-To: <20251015125911.0f0ebf87b278324667c4dfc5@linux-foundation.org> X-Rspam-User: X-Rspamd-Queue-Id: 207CA10000A X-Rspamd-Server: rspam02 X-Stat-Signature: da34fwowfztkan4gxbxp6xwm5ebuszrh X-HE-Tag: 1760558943-283974 X-HE-Meta: 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 t7aVGnUP PJO4vlCAwGG/7G6b0+hFYhaV8hod0ExJ8WZjgFhIz+QXieKAOFSgTwrEz1MCOMR05V2RfVepvvQp6t+pR4bPleiv0bmEEJPxU0VIOqc30F31sYC3QJZgwPu3irxka/CvrbS0hdxVqG5YsPog71csYwho3lVp1l3ljR4PlhD0MBi4dYWrN9m1h/h0OvXTMTzLDjxquUw74dpta48sC2oeHx4FJh82kC6G8t6XLNEun7DFMJ/IUEjJhwLuuUqSUb6OdCYUcHmUv4QVgOwfzdWlkUDYDpW4/EtonNFl6QGLi4wkfB1qWw+Isg0JLkQ/rK8vRY08RhzVr0VoxMzDYg0e9Jax2B4JEZQ8sOHTTcdIPIph8rjoRY/S7b70q0ggsSfO0R35A 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 Wed, Oct 15, 2025 at 12:59:11PM -0700, Andrew Morton wrote: > On Wed, 8 Oct 2025 18:06:07 +0000 Dmitry Ilvokhin wrote: > > > > > + * They might be still in mlock_fbatch waiting to be processed > > > > + * and activating it here might interfere with > > > > + * mlock_folio_batch(). __mlock_folio() will fail > > > > + * folio_test_clear_lru() check and give up. It happens because > > > > + * __folio_batch_add_and_move() clears LRU flag, when adding > > > > + * folio to activate batch. > > > > + */ > > > > > > This makes sense as activating an mlocked folio should be a noop but I > > > am wondering why we are seeing this now. By this, I mean mlock()ed > > > memory being delayed to get to unevictable LRU. Also I remember Hugh > > > recently [1] removed the difference betwen mlock percpu cache and other > > > percpu caches of clearing LRU bit on entry. Does you repro work even > > > with Hugh's changes or without it? > > > > > > > Thanks Shakeel for mentioning Hugh's patch, I was not aware of it. > > Indeed, I could not reproduce problem on top of Hugh's patch anymore, > > which totally make sense, because folio_test_clear_lru() is gone from > > __folio_batch_add_and_move(). > > > > Now I wonder does folio_test_mlocked() check still make sense in the > > current codebase? > > > > > [1] https://lore.kernel.org/all/05905d7b-ed14-68b1-79d8-bdec30367eba@google.com/ > > So I take it that this patch ("mm: skip folio_activate() for mlocked > folios") is no longer needed? Yes, this is my understanding as well. Hugh's patch addressed initial problem and this patch is no longer needed.