From 108b6a78463bb8c7163e4f9779f36ad8bbade334 Mon Sep 17 00:00:00 2001 From: Daisuke Nishimura Date: Tue, 26 Jul 2011 16:08:25 -0700 Subject: [PATCH] memcg: fix behavior of mem_cgroup_resize_limit() Commit 22a668d7c3ef ("memcg: fix behavior under memory.limit equals to memsw.limit") introduced "memsw_is_minimum" flag, which becomes true when mem_limit == memsw_limit. The flag is checked at the beginning of reclaim, and "noswap" is set if the flag is true, because using swap is meaningless in this case. This works well in most cases, but when we try to shrink mem_limit, which is the same as memsw_limit now, we might fail to shrink mem_limit because swap doesn't used. This patch fixes this behavior by: - check MEM_CGROUP_RECLAIM_SHRINK at the begining of reclaim - If it is set, don't set "noswap" flag even if memsw_is_minimum is true. Signed-off-by: Daisuke Nishimura Cc: Balbir Singh Acked-by: KAMEZAWA Hiroyuki Cc: Michal Hocko Cc: Ying Han Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/memcontrol.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index c0b065ec1571..dfeca594fd7a 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1653,7 +1653,7 @@ static int mem_cgroup_hierarchical_reclaim(struct mem_cgroup *root_mem, excess = res_counter_soft_limit_excess(&root_mem->res) >> PAGE_SHIFT; /* If memsw_is_minimum==1, swap-out is of-no-use. */ - if (!check_soft && root_mem->memsw_is_minimum) + if (!check_soft && !shrink && root_mem->memsw_is_minimum) noswap = true; while (1) {