diff --git a/block/elevator.c b/block/elevator.c
index 980f8ae..902dd13 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -1110,6 +1110,8 @@
 	queue_flag_clear(QUEUE_FLAG_ELVSWITCH, q);
 	spin_unlock_irq(q->queue_lock);
 
+	blk_add_trace_msg(q, "elv switch: %s", e->elevator_type->elevator_name);
+
 	return 1;
 
 fail_register: