+}
+
+/*
+ * check whether the @pc is valid for moving account and call
+ * __mem_cgroup_move_account()
+ */
+static int mem_cgroup_move_account(struct page_cgroup *pc,
+ struct mem_cgroup *from, struct mem_cgroup *to)
+{
+ int ret = -EINVAL;
+ lock_page_cgroup(pc);
+ if (PageCgroupUsed(pc) && pc->mem_cgroup == from) {
+ __mem_cgroup_move_account(pc, from, to);
+ ret = 0;
+ }
+ unlock_page_cgroup(pc);