mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-09-27 12:57:53 +00:00
Code Issues Releases Wiki Activity

mm/memcg: add oom_group_kill memory event

Browse source 
Our container agent wants to know when a container exits if it was OOM
killed or not to report to the user.  We use memory.oom.group = 1 to
ensure that OOM kills within the container's cgroup kill everything.
Existing memory.events are insufficient for knowing if this triggered:

1) Our current approach reads memory.events oom_kill and reports the
   container was killed if the value is non-zero. This is erroneous in
   some cases where containers create their children cgroups with
   memory.oom.group=1 as such OOM kills will get counted against the
   container cgroup's oom_kill counter despite not actually OOM killing
   the entire container.

2) Reading memory.events.local will fail to identify OOM kills in leaf
   cgroups (that don't set memory.oom.group) within the container
   cgroup.

This patch adds a new oom_group_kill event when memory.oom.group
triggers to allow userspace to cleanly identify when an entire cgroup is
oom killed.

[schatzberg.dan@gmail.com: changes from Johannes and Chris]
  Link: https://lkml.kernel.org/r/20211213162511.2492267-1-schatzberg.dan@gmail.com

Link: https://lkml.kernel.org/r/20211203162426.3375036-1-schatzberg.dan@gmail.com
Signed-off-by: Dan Schatzberg <schatzberg.dan@gmail.com>
Reviewed-by: Roman Gushchin <guro@fb.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Chris Down <chris@chrisdown.name>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Zefan Li <lizefan.x@bytedance.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Alex Shi <alexs@kernel.org>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Dan Schatzberg 2022-01-14 14:05:35 -08:00 committed by Linus Torvalds
parent 46a53371f3
commit b6bf9abb0a
4 changed files with 7 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

3
Documentation/admin-guide/cgroup-v2.rst
View file

@ -1268,6 +1268,9 @@ PAGE_SIZE multiple when read back.
The number of processes belonging to this cgroup
killed by any kind of OOM killer.
oom_group_kill
The number of times a group OOM has occurred.
memory.events.local
Similar to memory.events but the fields in the file are local
to the cgroup i.e. not hierarchical. The file modified event

1
include/linux/memcontrol.h
View file

@ -42,6 +42,7 @@ enum memcg_memory_event {
MEMCG_MAX,
MEMCG_OOM,
MEMCG_OOM_KILL,
MEMCG_OOM_GROUP_KILL,
MEMCG_SWAP_HIGH,
MEMCG_SWAP_MAX,
MEMCG_SWAP_FAIL,

2
mm/memcontrol.c
View file

@ -6318,6 +6318,8 @@ static void __memory_events_show(struct seq_file *m, atomic_long_t *events)
seq_printf(m, "oom %lu\n", atomic_long_read(&events[MEMCG_OOM]));
seq_printf(m, "oom_kill %lu\n",
atomic_long_read(&events[MEMCG_OOM_KILL]));
seq_printf(m, "oom_group_kill %lu\n",
atomic_long_read(&events[MEMCG_OOM_GROUP_KILL]));
}
static int memory_events_show(struct seq_file *m, void *v)

1
mm/oom_kill.c
View file

@ -994,6 +994,7 @@ static void oom_kill_process(struct oom_control *oc, const char *message)
* If necessary, kill all tasks in the selected memory cgroup.
*/
if (oom_group) {
memcg_memory_event(oom_group, MEMCG_OOM_GROUP_KILL);
mem_cgroup_print_oom_group(oom_group);
mem_cgroup_scan_tasks(oom_group, oom_kill_memcg_member,
(void *)message);