From: Daisuke Nishimura <nishim...@mxp.nes.nec.co.jp>
22a668d7 ("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 <nishim...@mxp.nes.nec.co.jp>
Cc: Balbir Singh <bsinghar...@gmail.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hir...@jp.fujitsu.com>
Cc: Michal Hocko <mho...@suse.cz>
Cc: Ying Han <ying...@google.com>
Cc: <sta...@kernel.org>
Signed-off-by: Andrew Morton <a...@linux-foundation.org>
---
mm/memcontrol.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff -puN mm/memcontrol.c~memcg-fix-behavior-of-mem_cgroup_resize_limit
mm/memcontrol.c
--- a/mm/memcontrol.c~memcg-fix-behavior-of-mem_cgroup_resize_limit
+++ a/mm/memcontrol.c
@@ -1653,7 +1653,7 @@ static int mem_cgroup_hierarchical_recla
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) {
_
_______________________________________________
stable mailing list
stable@linux.kernel.org
http://linux.kernel.org/mailman/listinfo/stable
