From: Li RongQing <roy.qing.li@xxxxxxxxx> The margin may be set to the difference value between memory limit and memory count firstly. which maybe returned wrongly if memsw.count excess memsw.limit, because try_charge forces charging __GFP_NOFAIL allocations, which may result in memsw.limit excess. If we are below memory.limit and there's nothing to reclaim to reduce memsw.usage, might end up looping in try_charge forever. Signed-off-by: Li RongQing <roy.qing.li@xxxxxxxxx> Acked-by: Vladimir Davydov <vdavydov@xxxxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> --- mm/memcontrol.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 00981d2..12aaadd 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -1090,6 +1090,8 @@ static unsigned long mem_cgroup_margin(struct mem_cgroup *memcg) limit = READ_ONCE(memcg->memsw.limit); if (count <= limit) margin = min(margin, limit - count); + else + margin = 0; } return margin; -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe cgroups" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
