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From: Usama Arif In-Reply-To: <4752c658-7b61-4636-ab5b-bd172e11a42c@linux.dev> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT X-Rspamd-Queue-Id: B6588160005 X-Stat-Signature: pubff9bsgz38qxxuqbxajb7ohe1nkemj X-Rspam-User: X-Rspamd-Server: rspam12 X-HE-Tag: 1783956900-240173 X-HE-Meta: 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 DkjH3l68 QqeDDGBNGTkdVZ16kJHFMPCzn2lPK7cE3Z7xx0v3NOeHo5s0uJyUuzjgcpw/IHMy76LAdhpiBfY3wyPpGHM/kWaAgDS3qn+YPWlmBiHbmkMcwfDXnxz57gQUUrbYUg9j2sUGdt44fhJxPbILapvXqOBS5Jt5VbgqypsXRyOKnuJ6ohw/76iNAgL3Ma+EHB4D+6NiXGhvIsTsaNAqRQlvQ9uPWAyHk+3PI267off1LK8hvO2qpWCU6mFp5N/Ta+BdkSl5hgzzcIm72/Gv4D2BpGnU6vQ== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 13/07/2026 14:12, Qi Zheng wrote: > Hi Usama, > > On 6/9/26 8:30 PM, Usama Arif wrote: >> The super_block shrinker is registered with SHRINKER_MEMCG_AWARE because its >> dentry and inode LRUs are memcg-aware (via list_lru). But the optional >> ->nr_cached_objects() hooks that the shrinker also drives are not memcg-aware: >> btrfs extent maps and xfs inode reclaim operate on filesystem-global >> state, and shmem's unused-huge shrinker walks a per-superblock shrinklist. >> None of them filter by sc->memcg. > > This makes sense for now, but how should we handle this if these > shrinkers are made memcg-aware in the future? > > I've recently been working on making the shmem huge shrinker > memcg-aware, but noticed my changes broke after rebasing onto the latest > tree, which led me to this patch. > > As for the shmem huge shrinker, I can work around this limitation by > making it a separate shrinker. But this feels more like an overall > design decision, effectively meaning that all nr_cached_objects are > precluded from being memcg-aware. > > Thanks, > Qi > Hi Qi, Thanks for raising this. I think the alternative is what I mentioned in https://lore.kernel.org/all/cfdb8620-ea55-4226-98bf-d006820e6270@linux.dev/ move this down to the fs own callbacks instead of here. Would that be better? Thanks, Usama