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dkim=pass header.d=google.com header.s=20210112 header.b=AQ8i7b3O; spf=pass (imf15.hostedemail.com: domain of shakeelb@google.com designates 209.85.214.171 as permitted sender) smtp.mailfrom=shakeelb@google.com; dmarc=pass (policy=reject) header.from=google.com X-Stat-Signature: bcarbww5o4mwhn8aazet5drngm3gi6z1 X-Rspamd-Queue-Id: E2815A0048 X-HE-Tag: 1656826600-522192 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000060, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Sat, Jul 2, 2022 at 8:39 AM Roman Gushchin wrote: > > On Fri, Jul 01, 2022 at 10:50:40PM -0700, Shakeel Butt wrote: > > On Fri, Jul 1, 2022 at 8:35 PM Roman Gushchin wrote: > > > > > > Yafang Shao reported an issue related to the accounting of bpf > > > memory: if a bpf map is charged indirectly for memory consumed > > > from an interrupt context and allocations are enforced, MEMCG_MAX > > > events are not raised. > > > > > > It's not/less of an issue in a generic case because consequent > > > allocations from a process context will trigger the reclaim and > > > MEMCG_MAX events. However a bpf map can belong to a dying/abandoned > > > memory cgroup, so it might never happen. > > > > The patch looks good but the above sentence is confusing. What might > > never happen? Reclaim or MAX event on dying memcg? > > Direct reclaim and MAX events. I agree it might be not clear without > looking into the code. How about something like this? > > "It's not/less of an issue in a generic case because consequent > allocations from a process context will trigger the direct reclaim > and MEMCG_MAX events will be raised. However a bpf map can belong > to a dying/abandoned memory cgroup, so there will be no allocations > from a process context and no MEMCG_MAX events will be triggered." > SGTM and you can add: Acked-by: Shakeel Butt