The patch titled
     memcg: fix behavior of mem_cgroup_resize_limit()
has been added to the -mm tree.  Its filename is
     memcg-fix-behavior-of-mem_cgroup_resize_limit.patch

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------------------------------------------------------
Subject: memcg: fix behavior of mem_cgroup_resize_limit()
From: Daisuke Nishimura <[email protected]>

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 <[email protected]>
Cc: Balbir Singh <[email protected]>
Cc: KAMEZAWA Hiroyuki <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Ying Han <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
---

 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
@@ -1652,7 +1652,7 @@ 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) {
_

Patches currently in -mm which might be from [email protected] are

mm-preallocate-page-before-lock_page-at-filemap-cow.patch
memcg-export-memory-cgroups-swappiness-with-mem_cgroup_swappiness.patch
memcg-consolidates-memory-cgroup-lru-stat-functions.patch
memcg-consolidates-memory-cgroup-lru-stat-functions-fix.patch
memcg-fix-vmscan-count-in-small-memcgs.patch
memcg-fix-behavior-of-mem_cgroup_resize_limit.patch
memcg-add-memoryvmscan_stat.patch

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