diff --git a/init.c b/init.c
index 6599729..d860179 100644
--- a/init.c
+++ b/init.c
@@ -466,7 +466,7 @@
 			f->real_file_size = -1ULL;
 	}
 
-	td->mutex = fio_sem_init(0);
+	td->mutex = fio_mutex_init(0);
 
 	td->ts.clat_stat[0].min_val = td->ts.clat_stat[1].min_val = ULONG_MAX;
 	td->ts.slat_stat[0].min_val = td->ts.slat_stat[1].min_val = ULONG_MAX;