memcg, kmem: rename cache_from_memcg to cache_from_memcg_idx

We can't see the relationship with memcg from the parameters,
so the name with memcg_idx would be more reasonable.

Signed-off-by: Qiang Huang <h.huangqiang@huawei.com>
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Glauber Costa <glommer@parallels.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/slab.c b/mm/slab.c
index 2580db0..0c8967b 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -3982,7 +3982,7 @@
 
 	VM_BUG_ON(!mutex_is_locked(&slab_mutex));
 	for_each_memcg_cache_index(i) {
-		c = cache_from_memcg(cachep, i);
+		c = cache_from_memcg_idx(cachep, i);
 		if (c)
 			/* return value determined by the parent cache only */
 			__do_tune_cpucache(c, limit, batchcount, shared, gfp);
diff --git a/mm/slab.h b/mm/slab.h
index a535033..0859c42 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -160,7 +160,8 @@
 	return s->name;
 }
 
-static inline struct kmem_cache *cache_from_memcg(struct kmem_cache *s, int idx)
+static inline struct kmem_cache *
+cache_from_memcg_idx(struct kmem_cache *s, int idx)
 {
 	if (!s->memcg_params)
 		return NULL;
@@ -204,7 +205,8 @@
 	return s->name;
 }
 
-static inline struct kmem_cache *cache_from_memcg(struct kmem_cache *s, int idx)
+static inline struct kmem_cache *
+cache_from_memcg_idx(struct kmem_cache *s, int idx)
 {
 	return NULL;
 }
diff --git a/mm/slab_common.c b/mm/slab_common.c
index e2e98af..0b7bb39 100644
--- a/mm/slab_common.c
+++ b/mm/slab_common.c
@@ -571,7 +571,7 @@
 		return;
 
 	for_each_memcg_cache_index(i) {
-		c = cache_from_memcg(s, i);
+		c = cache_from_memcg_idx(s, i);
 		if (!c)
 			continue;
 
diff --git a/mm/slub.c b/mm/slub.c
index c3eb3d3..92737a0 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -4983,7 +4983,7 @@
 		 * through the descendants with best-effort propagation.
 		 */
 		for_each_memcg_cache_index(i) {
-			struct kmem_cache *c = cache_from_memcg(s, i);
+			struct kmem_cache *c = cache_from_memcg_idx(s, i);
 			if (c)
 				attribute->store(c, buf, len);
 		}