diff --git a/mm/swap_slots.c b/mm/swap_slots.c
index a791411fed71663af9839f8c2a4cfaba42ddedca..008ccb22fee6c3057fffa1fd3f0713767614cbfb 100644
--- a/mm/swap_slots.c
+++ b/mm/swap_slots.c
@@ -38,9 +38,9 @@ static DEFINE_PER_CPU(struct swap_slots_cache, swp_slots);
 static bool	swap_slot_cache_active;
 bool	swap_slot_cache_enabled;
 static bool	swap_slot_cache_initialized;
-DEFINE_MUTEX(swap_slots_cache_mutex);
+static DEFINE_MUTEX(swap_slots_cache_mutex);
 /* Serialize swap slots cache enable/disable operations */
-DEFINE_MUTEX(swap_slots_cache_enable_mutex);
+static DEFINE_MUTEX(swap_slots_cache_enable_mutex);
 
 static void __drain_swap_slots_cache(unsigned int type);
 static void deactivate_swap_slots_cache(void);