diff --git a/tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-snapshot.tc b/tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-snapshot.tc
index 79ce7d51350b37c4544159d00be8774e688f2b4e..df246e505af7d2b82a136f06f13b4d2dc43f9427 100644
--- a/tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-snapshot.tc
+++ b/tools/testing/selftests/ftrace/test.d/trigger/trigger-trace-marker-snapshot.tc
@@ -39,10 +39,10 @@ test_trace() {
 	fi
 	echo "testing $line for >$x<"
 	match=`echo $line | sed -e "s/>$x<//"`
-	if [ "$line" == "$match" ]; then
+	if [ "$line" = "$match" ]; then
 	    fail "$line does not have >$x< in it"
 	fi
-	let x=$x+2
+	x=$((x+2))
     done
 }