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Mercier" , roman.gushchin@linux.dev, muchun.song@linux.dev, Andrew Morton , Kairui Song , Qi Zheng , Shakeel Butt , Barry Song , Axel Rasmussen , Yuanchu Xie , Wei Xu , Baoquan He , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Jonathan Corbet , Shuah Khan , Randy Dunlap , Johannes Weiner Cc: cgroups@vger.kernel.org, linux-mm@kvack.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org References: <20261028010611.3929937-1-tjmercier@google.com> <20261028010611.3929937-3-tjmercier@google.com> From: Baolin Wang In-Reply-To: <20261028010611.3929937-3-tjmercier@google.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 46EE0100002 X-Stat-Signature: yqa1nay9sm6hj6n775fe4cnetjc3t839 X-Rspam-User: X-Spam-Status: No, score=-19.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,SPF_HELO_PASS,SPF_PASS, UNPARSEABLE_RELAY,USER_AGENT_SANE_1,USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=4.0.1 X-HE-Tag: 1793254151-238666 X-HE-Meta: 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 f1cQb36M Z4TSaUpV6OYY8EqSLxC7Sn5OQxxLrg9vcUk8/bFmI74nDj12XzKzBu6rp+yPnLLDqWiT7N3hWG5L1bbx84T1D6ed5Wxvtyv0ZBXWbk/npPtRWmcg/39R506txZlT1vq2uxfz0YG3V/lR/GxPI6nlsYwRkiHMJhcQitfgZd4muDKx2INc4LS+zhPpaB5PZ5NczfQ8WBFdxuq1EzMQURIZPpTKt8pTPuo1kvUHRzJiMV+zD7oRingZfgsjCnUjJKsldkglA4HpyDn7J5dvyl4qf6gHZB0SE6WbOJOzzwHdr0KjuNg+IlS9U3jvdg+kxsLj07VA55I7An5bNVwQ= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On 10/28/26 9:06 AM, T.J. Mercier wrote: > lru_gen_offline_memcg() moves an offlining memcg to the head of the old > generation of the memcg LRU (MEMCG_LRU_OLD), so that global reclaim > visits it first and evicts the folios it left behind. > > Since commit f1cf8d2f36dc ("mm: memcontrol: eliminate the problem of > dying memory cgroup for LRU folios"), those folios are reparented to the > parent before lru_gen_offline_memcg() runs, and nothing can be added > back to the offlined memcg's lruvec afterwards. Putting an empty > offlined memcg at the head of the old generation no longer serves any > purpose and only delays reclaim from the memcgs that still have memory > due to additional shrink_many() iteration. > > Remove lru_gen_offline_memcg(), so that an offlined memcg is rotated > like any other memcg below the reclaimable size threshold until > lru_gen_release_memcg() takes it off the memcg LRU. MEMCG_LRU_OLD has no > other user, so remove the op and update the memcg LRU comment as well. > > Signed-off-by: T.J. Mercier > --- Thanks for the cleanups. LGTM. Reviewed-by: Baolin Wang