-/* keepalive_stacks could be a per-stack var to avoid locking overhead */
-static MonoGHashTable *keepalive_stacks = NULL;
-static CRITICAL_SECTION tasklets_mutex;
-#define tasklets_lock() EnterCriticalSection(&tasklets_mutex)
-#define tasklets_unlock() LeaveCriticalSection(&tasklets_mutex)
+static mono_mutex_t tasklets_mutex;
+#define tasklets_lock() mono_mutex_lock(&tasklets_mutex)
+#define tasklets_unlock() mono_mutex_unlock(&tasklets_mutex)