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charset=us-ascii Content-Disposition: inline X-Rspamd-Queue-Id: D6E63180017 X-Rspam-User: X-Rspamd-Server: rspam02 X-Stat-Signature: xyrb5bsfgbit1nguam4bwgft3b4kqbwe X-HE-Tag: 1692028653-39072 X-HE-Meta: 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 kwtVMU35 mqt12qpECuP2l+IIoJlEO/mOFZPXahm2MVh8JeHbKkn8rXriI+ZEKhqmf3IKA5RniogqTUaUjmzuo/qODtdBR+JdVUmwvclZZOn2OcUGhBeuhxnBQjwhRMMMq9VBUG1mt6MIDonPxic5OeHDHot6frgTMVeHOTT6KrXdHwxNRc/IWfTCQFPunlfuUYSKeb8KFe6KMK7aOnsfAiY7op408xZQSfUE1mmj7ti+e11oZAxSpwqpHIC3+n7fCJsDKfXMeH2mHBbtq5ZqID4Rom2zwv3r0tzN6GdkO9d7GJXqyOUbhvTjJL6h42AOIna+8jUVYIT0adx7om3ZvE38ka76yP1kzFWoBm0vcEhWHyfLmwxyVNfnQ78qw9eWeYTJwUqzNDz0NzYWFzM5Oeo+JEE5T4sMHRuRtBItmoaoXoG3PnYVp6Jcq787yBEi6prUL+2F7tKiaWsCFroyskvvznxfWR6cWEpRHwGUWtMTEBnC2pPQIu29G/daTtGWcJoIe/fabCYlmV2TXz2Kc5eTnGBRcSllLDYFwZ7WbPM1rTjspu/AUbiY= 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: On Fri, Aug 04, 2023 at 02:59:28PM -0400, Lucas Karpinski wrote: > On Fri, Aug 04, 2023 at 12:37:16PM -0400, Johannes Weiner wrote: > > On Fri, Aug 04, 2023 at 11:37:33AM -0400, Lucas Karpinski wrote: > > > The test allocates dcache inside a cgroup, then destroys the cgroups and > > > then checks the sanity of numbers on the parent level. The reason it > > > fails is because dentries are freed with an RCU delay - a debugging > > > sleep shows that usage drops as expected shortly after. > > > > > > Insert a 1s sleep after completing the cgroup creation/deletions. This > > > should be good enough, assuming that machines running those tests are > > > otherwise not very busy. This commit is directly inspired by Johannes > > > over at the link below. > > > > > > Link: https://lore.kernel.org/all/20230801135632.1768830-1-hannes@cmpxchg.org/ > > > > > > Signed-off-by: Lucas Karpinski > > > > Maybe I'm missing something, but there isn't a limit set anywhere that > > would cause the dentries to be reclaimed and freed, no? When the > > subgroups are deleted, the objects are just moved to the parent. The > > counters inside the parent (which are hierarchical) shouldn't change. > > > > So this seems to be a different scenario than test_kmem_basic. If the > > test is failing for you, I can't quite see why. > > > You're right, the parent inherited the counters and it should behave > the same whether I'm directly removing the child or if I was moving it > under another cgroup. I do see the behaviour you described on my > x86_64 setup, but the wrong behaviour on my aarch64 dev. platform. I'll > take a closer look, but just wanted to leave an example here of what I > see. > > Example of slab size pre/post sleep: > slab_pre = 18164688, slab_post = 3360000 > > Thanks, > Lucas Looked into the failures and I do have a proposed solution, just want some feedback first. With how the kernel entry in memory.stat is updated, it takes into account all charged / uncharged pages, it looks like it makes more sense to use that single entry rather than `slab + anon + file + kernel_stack + pagetables + percpu + sock' as it would cover all utilization. Thanks, Lucas