[PATCH RFC] memcg: notify about global mem_cgroup_id space depletion

[Vasily Averin]

Currently host owner is not informed about the exhaustion of the
global mem_cgroup_id space. When this happens, systemd cannot
start a new service, but nothing points to the real cause of
this failure.

Signed-off-by: Vasily Averin <vvs@xxxxxxxxxx>
---
 mm/memcontrol.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index d4c606a06bcd..5229321636f2 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -5317,6 +5317,7 @@ static struct mem_cgroup *mem_cgroup_alloc(void)
 				 1, MEM_CGROUP_ID_MAX + 1, GFP_KERNEL);
 	if (memcg->id.id < 0) {
 		error = memcg->id.id;
+		pr_notice_ratelimited("mem_cgroup_id space is exhausted\n");
 		goto fail;
 	}
 
-- 
2.36.1