diff --git a/tools/testing/selftests/ftrace/test.d/event/toplevel-enable.tc b/tools/testing/selftests/ftrace/test.d/event/toplevel-enable.tc
index 0bb5df3c00d41701f7392c73c31c95b10867f1d8..15e2d3fe1731788bb4fa66163ff8830d4db2933e 100644
--- a/tools/testing/selftests/ftrace/test.d/event/toplevel-enable.tc
+++ b/tools/testing/selftests/ftrace/test.d/event/toplevel-enable.tc
@@ -28,7 +28,9 @@ echo '*:*' > set_event
 
 yield
 
-count=`cat trace | grep -v ^# | wc -l`
+echo 0 > tracing_on
+
+count=`head -n 128 trace | grep -v ^# | wc -l`
 if [ $count -eq 0 ]; then
     fail "none of events are recorded"
 fi
@@ -36,10 +38,12 @@ fi
 do_reset
 
 echo 1 > events/enable
+echo 1 > tracing_on
 
 yield
 
-count=`cat trace | grep -v ^# | wc -l`
+echo 0 > tracing_on
+count=`head -n 128 trace | grep -v ^# | wc -l`
 if [ $count -eq 0 ]; then
     fail "none of events are recorded"
 fi