1 files changed, 1 insertions, 1 deletions

diff --git a/unit_trace/viz/schedule.py b/unit_trace/viz/schedule.py
index ec6398d..542524b 100644
--- a/unit_trace/viz/schedule.py
+++ b/unit_trace/viz/schedule.py
@@ -250,7 +250,7 @@ class Schedule(object):
             for event in EVENT_LIST:
                 switch_event = switches[event]
                 if switch_event is not None:
-                    event.fill_span_event_from_start()
+                    switch_event.fill_span_event_from_start()
 
         # add events that correspond to the tasks and CPUS, at the very beginning
         self.time_slot_array.add_item_dummies(self)