[PATCH] mm: memcontrol: drain stocks on resize limit

From: Shakeel Butt
Date: Fri May 04 2018 - 16:56:02 EST


Resizing the memcg limit for cgroup-v2 drains the stocks before
triggering the memcg reclaim. Do the same for cgroup-v1 to make the
behavior consistent.

Signed-off-by: Shakeel Butt <shakeelb@xxxxxxxxxx>
---
mm/memcontrol.c | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 25b148c2d222..e2d33a37f971 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -2463,6 +2463,7 @@ static int mem_cgroup_resize_max(struct mem_cgroup *memcg,
unsigned long max, bool memsw)
{
bool enlarge = false;
+ bool drained = false;
int ret;
bool limits_invariant;
struct page_counter *counter = memsw ? &memcg->memsw : &memcg->memory;
@@ -2493,6 +2494,12 @@ static int mem_cgroup_resize_max(struct mem_cgroup *memcg,
if (!ret)
break;

+ if (!drained) {
+ drain_all_stock(memcg);
+ drained = true;
+ continue;
+ }
+
if (!try_to_free_mem_cgroup_pages(memcg, 1,
GFP_KERNEL, !memsw)) {
ret = -EBUSY;
--
2.17.0.441.gb46fe60e1d-goog