slub: fix memcg_propagate_slab_attrs
After creating a cache for a memcg we should initialize its sysfs attrs
with the values from its parent. That's what memcg_propagate_slab_attrs
is for. Currently it's broken - we clearly muddled root-vs-memcg caches
there. Let's fix it up.
Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/slub.c b/mm/slub.c
index 5e234f1..042a47b 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -5071,15 +5071,18 @@
#ifdef CONFIG_MEMCG_KMEM
int i;
char *buffer = NULL;
+ struct kmem_cache *root_cache;
- if (!is_root_cache(s))
+ if (is_root_cache(s))
return;
+ root_cache = s->memcg_params->root_cache;
+
/*
* This mean this cache had no attribute written. Therefore, no point
* in copying default values around
*/
- if (!s->max_attr_size)
+ if (!root_cache->max_attr_size)
return;
for (i = 0; i < ARRAY_SIZE(slab_attrs); i++) {
@@ -5101,7 +5104,7 @@
*/
if (buffer)
buf = buffer;
- else if (s->max_attr_size < ARRAY_SIZE(mbuf))
+ else if (root_cache->max_attr_size < ARRAY_SIZE(mbuf))
buf = mbuf;
else {
buffer = (char *) get_zeroed_page(GFP_KERNEL);
@@ -5110,7 +5113,7 @@
buf = buffer;
}
- attr->show(s->memcg_params->root_cache, buf);
+ attr->show(root_cache, buf);
attr->store(s, buf, strlen(buf));
}