From mboxrd@z Thu Jan 1 00:00:00 1970 From: Roman Gushchin Subject: Re: [PATCH 3/5] cgroup: Account for memory_localevents in test_memcg_oom_group_leaf_events() Date: Fri, 22 Apr 2022 16:14:49 -0700 Message-ID: References: <20220422155728.3055914-1-void@manifault.com> <20220422155728.3055914-4-void@manifault.com> Mime-Version: 1.0 Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1650669295; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=qj54Vyot11RQURjSDei20EVpyRPh4pQqH20/VoPb/oY=; b=WWhuDxynQAO8T0s74G33tChZVeFVDym7JxNZ5avEQ2CPZNMh9wqOtfLPt/wrG1+5WwfSTu 7yjlJ2fQ+56QPdJsoOiM/ZahjDyqpieegEXLu4PcOhG+OOBZx8RlLBwzKpDN9ekV7CSFx2 fXn8qs8BVdRh/bFx1bRkHLItH8xTB6w= Content-Disposition: inline In-Reply-To: <20220422155728.3055914-4-void-gq6j2QGBifHby3iVrkZq2A@public.gmane.org> List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: David Vernet Cc: akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org, tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org, mhocko-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, shakeelb-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, kernel-team-b10kYP2dOMg@public.gmane.org On Fri, Apr 22, 2022 at 08:57:27AM -0700, David Vernet wrote: > The test_memcg_oom_group_leaf_events() testcase in the cgroup memcg tests > validates that processes in a group that perform allocations exceeding > memory.oom.group are killed. It also validates that the > memory.events.oom_kill events are properly propagated in this case. Commit > 06e11c907ea4 ("kselftests: memcg: update the oom group leaf events test") > fixed test_memcg_oom_group_leaf_events() to account for the fact that the > memory.events.oom_kill events in a child cgroup is propagated up to its > parent. This behavior can actually be configured by the memory_localevents > mount option, so this patch updates the testcase to properly account for > the possible presence of this mount option. > > Signed-off-by: David Vernet > --- > .../testing/selftests/cgroup/test_memcontrol.c | 17 ++++++++++++++++- > 1 file changed, 16 insertions(+), 1 deletion(-) > > diff --git a/tools/testing/selftests/cgroup/test_memcontrol.c b/tools/testing/selftests/cgroup/test_memcontrol.c > index ea2fd27e52df..d88e0ca3f3d1 100644 > --- a/tools/testing/selftests/cgroup/test_memcontrol.c > +++ b/tools/testing/selftests/cgroup/test_memcontrol.c > @@ -21,6 +21,7 @@ > #include "../kselftest.h" > #include "cgroup_util.h" > > +static bool has_localevents; > static bool has_recursiveprot; > > /* > @@ -1091,6 +1092,7 @@ static int test_memcg_oom_group_leaf_events(const char *root) > { > int ret = KSFT_FAIL; > char *parent, *child; > + long parent_oom_events; > > parent = cg_name(root, "memcg_test_0"); > child = cg_name(root, "memcg_test_0/memcg_test_1"); > @@ -1128,7 +1130,15 @@ static int test_memcg_oom_group_leaf_events(const char *root) > if (cg_read_key_long(child, "memory.events", "oom_kill ") <= 0) > goto cleanup; > > - if (cg_read_key_long(parent, "memory.events", "oom_kill ") <= 0) > + parent_oom_events = cg_read_key_long( > + parent, "memory.events", "oom_kill "); > + // If memory_localevents is not enabled (the default), the parent should > + // count OOM events in its children groups. Otherwise, it should not > + // have observed any events. Please, use /* */ style comments, it's a generic kernel style. > + if (has_localevents) { > + if (parent_oom_events != 0) > + goto cleanup; > + } else if (parent_oom_events <= 0) > goto cleanup; How about something like this? IMO a bit more clear what's going on. if ((has_local_events && parent_oom_events == 0) || parent_oom_events > 0) ret = KSFT_PASS; Anyway, looks good to me. Acked-by: Roman Gushchin > > ret = KSFT_PASS; > @@ -1298,6 +1308,11 @@ int main(int argc, char **argv) > ksft_exit_skip("Failed to query cgroup mount option\n"); > has_recursiveprot = proc_status; > > + proc_status = proc_mount_contains("memory_localevents"); > + if (proc_status < 0) > + ksft_exit_skip("Failed to query cgroup mount option\n"); > + has_localevents = proc_status; > + > for (i = 0; i < ARRAY_SIZE(tests); i++) { > switch (tests[i].fn(root)) { > case KSFT_PASS: > -- > 2.30.2 >