memcg: zap __memcg_{charge,uncharge}_slab

They are simple wrappers around memcg_{charge,uncharge}_kmem, so let's
zap them and call these functions directly.

Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 7c95af8..18ccb29 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -403,8 +403,9 @@
 struct kmem_cache *__memcg_kmem_get_cache(struct kmem_cache *cachep);
 void __memcg_kmem_put_cache(struct kmem_cache *cachep);
 
-int __memcg_charge_slab(struct kmem_cache *cachep, gfp_t gfp, int order);
-void __memcg_uncharge_slab(struct kmem_cache *cachep, int order);
+int memcg_charge_kmem(struct mem_cgroup *memcg, gfp_t gfp,
+		      unsigned long nr_pages);
+void memcg_uncharge_kmem(struct mem_cgroup *memcg, unsigned long nr_pages);
 
 int __memcg_cleanup_cache_params(struct kmem_cache *s);
 
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 8b58701..e229e3a 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -2495,8 +2495,8 @@
 	return cache_from_memcg_idx(cachep, memcg_cache_id(p->memcg));
 }
 
-static int memcg_charge_kmem(struct mem_cgroup *memcg, gfp_t gfp,
-			     unsigned long nr_pages)
+int memcg_charge_kmem(struct mem_cgroup *memcg, gfp_t gfp,
+		      unsigned long nr_pages)
 {
 	struct page_counter *counter;
 	int ret = 0;
@@ -2533,8 +2533,7 @@
 	return ret;
 }
 
-static void memcg_uncharge_kmem(struct mem_cgroup *memcg,
-				unsigned long nr_pages)
+void memcg_uncharge_kmem(struct mem_cgroup *memcg, unsigned long nr_pages)
 {
 	page_counter_uncharge(&memcg->memory, nr_pages);
 	if (do_swap_account)
@@ -2767,20 +2766,6 @@
 	current->memcg_kmem_skip_account = 0;
 }
 
-int __memcg_charge_slab(struct kmem_cache *cachep, gfp_t gfp, int order)
-{
-	unsigned int nr_pages = 1 << order;
-
-	return memcg_charge_kmem(cachep->memcg_params->memcg, gfp, nr_pages);
-}
-
-void __memcg_uncharge_slab(struct kmem_cache *cachep, int order)
-{
-	unsigned int nr_pages = 1 << order;
-
-	memcg_uncharge_kmem(cachep->memcg_params->memcg, nr_pages);
-}
-
 /*
  * Return the kmem_cache we're supposed to use for a slab allocation.
  * We try to use the current memcg's version of the cache.
diff --git a/mm/slab.h b/mm/slab.h
index 1cf40054..90430d6 100644
--- a/mm/slab.h
+++ b/mm/slab.h
@@ -235,7 +235,7 @@
 		return 0;
 	if (is_root_cache(s))
 		return 0;
-	return __memcg_charge_slab(s, gfp, order);
+	return memcg_charge_kmem(s->memcg_params->memcg, gfp, 1 << order);
 }
 
 static __always_inline void memcg_uncharge_slab(struct kmem_cache *s, int order)
@@ -244,7 +244,7 @@
 		return;
 	if (is_root_cache(s))
 		return;
-	__memcg_uncharge_slab(s, order);
+	memcg_uncharge_kmem(s->memcg_params->memcg, 1 << order);
 }
 #else
 static inline bool is_root_cache(struct kmem_cache *s)