The memcg_cache_params structure contains the common part and the union,
which represents two different types of data: one for root cashes and
another for child caches.
The size of child data is fixed. The size of the memcg_caches array is
calculated in runtime.
Currently the size of memcg_cache_params for root caches is calculated
incorrectly, because it includes the size of parameters for child caches.
ssize_t size = memcg_caches_array_size(num_groups);
size *= sizeof(void *);
size += sizeof(struct memcg_cache_params);
v2: Fix a typo in calculations
Cc: Glauber Costa <glommer@xxxxxxxxxx>
Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxx>
Cc: Balbir Singh <bsingharora@xxxxxxxxx>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Andrey Vagin <avagin@xxxxxxxxxx>
---
mm/memcontrol.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index c5792a5..2e47fea 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -3140,7 +3140,7 @@ int memcg_update_cache_size(struct kmem_cache *s, int num_groups)
ssize_t size = memcg_caches_array_size(num_groups);
size *= sizeof(void *);
- size += sizeof(struct memcg_cache_params);
+ size += offsetof(struct memcg_cache_params, memcg_caches);
s->memcg_params = kzalloc(size, GFP_KERNEL);
if (!s->memcg_params) {
@@ -3183,13 +3183,16 @@ int memcg_update_cache_size(struct kmem_cache *s, int num_groups)
int memcg_register_cache(struct mem_cgroup *memcg, struct kmem_cache *s,
struct kmem_cache *root_cache)
{
- size_t size = sizeof(struct memcg_cache_params);
+ size_t size;
if (!memcg_kmem_enabled())
return 0;
- if (!memcg)
+ if (!memcg) {
+ size = offsetof(struct memcg_cache_params, memcg_caches);
size += memcg_limited_groups_array_size * sizeof(void *);
+ } else
+ size = sizeof(struct memcg_cache_params);
s->memcg_params = kzalloc(size, GFP_KERNEL);
if (!s->memcg_params)
--
1.8.3.1
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>