diff --git a/tools/perf/tests/shell/coresight/unroll_loop_thread_10.sh b/tools/perf/tests/shell/coresight/unroll_loop_thread_10.sh
index f48c85230b15..7304e3d3a6ff 100755
--- a/tools/perf/tests/shell/coresight/unroll_loop_thread_10.sh
+++ b/tools/perf/tests/shell/coresight/unroll_loop_thread_10.sh
@@ -5,7 +5,7 @@
 # Carsten Haitzler <carsten.haitzler@arm.com>, 2021
 
 TEST="unroll_loop_thread"
-. $(dirname $0)/../lib/coresight.sh
+. "$(dirname $0)"/../lib/coresight.sh
 ARGS="10"
 DATV="10"
 DATA="$DATD/perf-$TEST-$DATV.data"