diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index bdc9582..76c0c99 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -4231,12 +4231,12 @@
 	unlock_page_cgroup(pc);
 	/*
 	 * even after unlock, we have memcg->res.usage here and this memcg
-	 * will never be freed.
+	 * will never be freed, so it's safe to call css_get().
 	 */
 	memcg_check_events(memcg, page);
 	if (do_swap_account && ctype == MEM_CGROUP_CHARGE_TYPE_SWAPOUT) {
 		mem_cgroup_swap_statistics(memcg, true);
-		mem_cgroup_get(memcg);
+		css_get(&memcg->css);
 	}
 	/*
 	 * Migration does not charge the res_counter for the
@@ -4348,7 +4348,7 @@
 
 	/*
 	 * record memcg information,  if swapout && memcg != NULL,
-	 * mem_cgroup_get() was called in uncharge().
+	 * css_get() was called in uncharge().
 	 */
 	if (do_swap_account && swapout && memcg)
 		swap_cgroup_record(ent, css_id(&memcg->css));
@@ -4379,7 +4379,7 @@
 		if (!mem_cgroup_is_root(memcg))
 			res_counter_uncharge(&memcg->memsw, PAGE_SIZE);
 		mem_cgroup_swap_statistics(memcg, false);
-		mem_cgroup_put(memcg);
+		css_put(&memcg->css);
 	}
 	rcu_read_unlock();
 }
@@ -4413,11 +4413,14 @@
 		 * This function is only called from task migration context now.
 		 * It postpones res_counter and refcount handling till the end
 		 * of task migration(mem_cgroup_clear_mc()) for performance
-		 * improvement. But we cannot postpone mem_cgroup_get(to)
-		 * because if the process that has been moved to @to does
-		 * swap-in, the refcount of @to might be decreased to 0.
+		 * improvement. But we cannot postpone css_get(to)  because if
+		 * the process that has been moved to @to does swap-in, the
+		 * refcount of @to might be decreased to 0.
+		 *
+		 * We are in attach() phase, so the cgroup is guaranteed to be
+		 * alive, so we can just call css_get().
 		 */
-		mem_cgroup_get(to);
+		css_get(&to->css);
 		return 0;
 	}
 	return -EINVAL;
@@ -6718,6 +6721,7 @@
 {
 	struct mem_cgroup *from = mc.from;
 	struct mem_cgroup *to = mc.to;
+	int i;
 
 	/* we must uncharge all the leftover precharges from mc.to */
 	if (mc.precharge) {
@@ -6738,7 +6742,9 @@
 		if (!mem_cgroup_is_root(mc.from))
 			res_counter_uncharge(&mc.from->memsw,
 						PAGE_SIZE * mc.moved_swap);
-		__mem_cgroup_put(mc.from, mc.moved_swap);
+
+		for (i = 0; i < mc.moved_swap; i++)
+			css_put(&mc.from->css);
 
 		if (!mem_cgroup_is_root(mc.to)) {
 			/*
@@ -6748,7 +6754,7 @@
 			res_counter_uncharge(&mc.to->res,
 						PAGE_SIZE * mc.moved_swap);
 		}
-		/* we've already done mem_cgroup_get(mc.to) */
+		/* we've already done css_get(mc.to) */
 		mc.moved_swap = 0;
 	}
 	memcg_oom_recover(from);