From 4d845ebf4cf9e985b1704b1f08b37f744b4ede13 Mon Sep 17 00:00:00 2001 From: KAMEZAWA Hiroyuki Date: Tue, 29 Jun 2010 15:05:18 -0700 Subject: [PATCH] memcg: fix wake up in oom wait queue OOM-waitqueue should be waken up when oom_disable is canceled. This is a fix for 3c11ecf448eff8f1 ("memcg: oom kill disable and oom status"). How to test: Create a cgroup A... 1. set memory.limit and memory.memsw.limit to be small value 2. echo 1 > /cgroup/A/memory.oom_control, this disables oom-kill. 3. run a program which must cause OOM. A program executed in 3 will sleep by oom_waiqueue in memcg. Then, how to wake it up is problem. 1. echo 0 > /cgroup/A/memory.oom_control (enable OOM-killer) 2. echo big mem > /cgroup/A/memory.memsw.limit_in_bytes(allow more swap) etc.. Without the patch, a task in slept can not be waken up. Signed-off-by: KAMEZAWA Hiroyuki Acked-by: Daisuke Nishimura Cc: Balbir Singh Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/memcontrol.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index c6ece0a57595..20a8193a7af8 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1370,7 +1370,7 @@ static void memcg_wakeup_oom(struct mem_cgroup *mem) static void memcg_oom_recover(struct mem_cgroup *mem) { - if (mem->oom_kill_disable && atomic_read(&mem->oom_lock)) + if (atomic_read(&mem->oom_lock)) memcg_wakeup_oom(mem); } @@ -3781,6 +3781,8 @@ static int mem_cgroup_oom_control_write(struct cgroup *cgrp, return -EINVAL; } mem->oom_kill_disable = val; + if (!val) + memcg_oom_recover(mem); cgroup_unlock(); return 0; } -- 2.20.1