From: Roman Gushchin Subject: kselftests: memcg: update the oom group leaf events test Patch series "mm: memcg kselftests fixes". This patch (of 4): Commit 9852ae3fe529 ("mm, memcg: consider subtrees in memory.events") made memory.events recursive: all events are propagated upwards by the tree. It was a change in semantics. It broke the oom group leaf events test: it assumes that after an OOM the oom_kill counter is zero on parent's level. Let's adjust the test: it should have similar expectations for the child and parent levels. The test passes after this fix. Link: https://lkml.kernel.org/r/20220415000133.3955987-2-roman.gushchin@linux.dev Link: https://lkml.kernel.org/r/20220415000133.3955987-1-roman.gushchin@linux.dev Signed-off-by: Roman Gushchin Reviewed-by: David Vernet Cc: Chris Down Cc: Johannes Weiner Cc: Michal Hocko Cc: Shakeel Butt Cc: Tejun Heo Cc: Zefan Li Signed-off-by: Andrew Morton --- tools/testing/selftests/cgroup/test_memcontrol.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/tools/testing/selftests/cgroup/test_memcontrol.c~kselftests-memcg-update-the-oom-group-leaf-events-test +++ a/tools/testing/selftests/cgroup/test_memcontrol.c @@ -1079,7 +1079,8 @@ cleanup: /* * This test disables swapping and tries to allocate anonymous memory * up to OOM with memory.group.oom set. Then it checks that all - * processes in the leaf (but not the parent) were killed. + * processes in the leaf were killed. It also checks that oom_events + * were propagated to the parent level. */ static int test_memcg_oom_group_leaf_events(const char *root) { @@ -1122,7 +1123,7 @@ static int test_memcg_oom_group_leaf_eve if (cg_read_key_long(child, "memory.events", "oom_kill ") <= 0) goto cleanup; - if (cg_read_key_long(parent, "memory.events", "oom_kill ") != 0) + if (cg_read_key_long(parent, "memory.events", "oom_kill ") <= 0) goto cleanup; ret = KSFT_PASS; _