The patch titled Subject: memcg, oom: simplify mem_cgroup_oom_synchronize has been added to the -mm mm-unstable branch. Its filename is memcg-oom-simplify-mem_cgroup_oom_synchronize.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/memcg-oom-simplify-mem_cgroup_oom_synchronize.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Haifeng Xu <haifeng.xu@xxxxxxxxxx> Subject: memcg, oom: simplify mem_cgroup_oom_synchronize Date: Fri, 7 Apr 2023 09:06:44 +0000 Since commit 29ef680ae7c2 ("memcg, oom: move out_of_memory back to the charge path"), only oom_kill_disable is set, oom killer will be delayed to page fault path. So the oom_kill_disable check is unnecessary. In the charge patch, even if the oom_lock in memcg can't be acquired, the oom handing can also be invoked. In order to keep the behavior consistent with it, remove the lock check. Also the explicit wakeup for the lock holder is unneeded because the lock contender won't be scheduled out. Link: https://lkml.kernel.org/r/20230407090644.399108-1-haifeng.xu@xxxxxxxxxx Signed-off-by: Haifeng Xu <haifeng.xu@xxxxxxxxxx> Suggested-by: Michal Hocko <mhocko@xxxxxxxxxx> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: Roman Gushchin <roman.gushchin@xxxxxxxxx> Cc: Shakeel Butt <shakeelb@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/memcontrol.c | 22 ++++------------------ 1 file changed, 4 insertions(+), 18 deletions(-) --- a/mm/memcontrol.c~memcg-oom-simplify-mem_cgroup_oom_synchronize +++ a/mm/memcontrol.c @@ -2027,26 +2027,12 @@ bool mem_cgroup_oom_synchronize(bool han if (locked) mem_cgroup_oom_notify(memcg); - if (locked && !READ_ONCE(memcg->oom_kill_disable)) { - mem_cgroup_unmark_under_oom(memcg); - finish_wait(&memcg_oom_waitq, &owait.wait); - mem_cgroup_out_of_memory(memcg, current->memcg_oom_gfp_mask, - current->memcg_oom_order); - } else { - schedule(); - mem_cgroup_unmark_under_oom(memcg); - finish_wait(&memcg_oom_waitq, &owait.wait); - } + schedule(); + mem_cgroup_unmark_under_oom(memcg); + finish_wait(&memcg_oom_waitq, &owait.wait); - if (locked) { + if (locked) mem_cgroup_oom_unlock(memcg); - /* - * There is no guarantee that an OOM-lock contender - * sees the wakeups triggered by the OOM kill - * uncharges. Wake any sleepers explicitly. - */ - memcg_oom_recover(memcg); - } cleanup: current->memcg_in_oom = NULL; css_put(&memcg->css); _ Patches currently in -mm which might be from haifeng.xu@xxxxxxxxxx are cpuset-clean-up-cpuset_node_allowed.patch memcg-oom-simplify-mem_cgroup_oom_synchronize.patch