#endif
 
 #ifdef CONFIG_MEMCG_KMEM
-int __memcg_kmem_charge(struct mem_cgroup *memcg, gfp_t gfp,
-                       unsigned int nr_pages);
-void __memcg_kmem_uncharge(struct mem_cgroup *memcg, unsigned int nr_pages);
 int __memcg_kmem_charge_page(struct page *page, gfp_t gfp, int order);
 void __memcg_kmem_uncharge_page(struct page *page, int order);
 
 
 #ifdef CONFIG_MEMCG_KMEM
 extern spinlock_t css_set_lock;
 
+static int __memcg_kmem_charge(struct mem_cgroup *memcg, gfp_t gfp,
+                              unsigned int nr_pages);
+static void __memcg_kmem_uncharge(struct mem_cgroup *memcg,
+                                 unsigned int nr_pages);
+
 static void obj_cgroup_release(struct percpu_ref *ref)
 {
        struct obj_cgroup *objcg = container_of(ref, struct obj_cgroup, refcnt);
  *
  * Returns 0 on success, an error code on failure.
  */
-int __memcg_kmem_charge(struct mem_cgroup *memcg, gfp_t gfp,
-                       unsigned int nr_pages)
+static int __memcg_kmem_charge(struct mem_cgroup *memcg, gfp_t gfp,
+                              unsigned int nr_pages)
 {
        struct page_counter *counter;
        int ret;
  * @memcg: memcg to uncharge
  * @nr_pages: number of pages to uncharge
  */
-void __memcg_kmem_uncharge(struct mem_cgroup *memcg, unsigned int nr_pages)
+static void __memcg_kmem_uncharge(struct mem_cgroup *memcg, unsigned int nr_pages)
 {
        if (!cgroup_subsys_on_dfl(memory_cgrp_subsys))
                page_counter_uncharge(&memcg->kmem, nr_pages);