summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--mm/memcontrol.c15
1 files changed, 14 insertions, 1 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index bc70254558fa..f96ccc90fa66 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -547,6 +547,11 @@ static void disarm_kmem_keys(struct mem_cgroup *memcg)
{
if (memcg_kmem_is_active(memcg))
static_key_slow_dec(&memcg_kmem_enabled_key);
+ /*
+ * This check can't live in kmem destruction function,
+ * since the charges will outlive the cgroup
+ */
+ WARN_ON(res_counter_read_u64(&memcg->kmem, RES_USAGE) != 0);
}
#else
static void disarm_kmem_keys(struct mem_cgroup *memcg)
@@ -4025,6 +4030,7 @@ static void mem_cgroup_force_empty_list(struct mem_cgroup *memcg,
static void mem_cgroup_reparent_charges(struct mem_cgroup *memcg)
{
int node, zid;
+ u64 usage;
do {
/* This is for making all *used* pages to be on LRU. */
@@ -4045,13 +4051,20 @@ static void mem_cgroup_reparent_charges(struct mem_cgroup *memcg)
cond_resched();
/*
+ * Kernel memory may not necessarily be trackable to a specific
+ * process. So they are not migrated, and therefore we can't
+ * expect their value to drop to 0 here.
+ * Having res filled up with kmem only is enough.
+ *
* This is a safety check because mem_cgroup_force_empty_list
* could have raced with mem_cgroup_replace_page_cache callers
* so the lru seemed empty but the page could have been added
* right after the check. RES_USAGE should be safe as we always
* charge before adding to the LRU.
*/
- } while (res_counter_read_u64(&memcg->res, RES_USAGE) > 0);
+ usage = res_counter_read_u64(&memcg->res, RES_USAGE) -
+ res_counter_read_u64(&memcg->kmem, RES_USAGE);
+ } while (usage > 0);
}
/*