diff --git a/tools/perf/util/smt.c b/tools/perf/util/smt.c
index 2b0a36ebf27a..8fed03283c85 100644
--- a/tools/perf/util/smt.c
+++ b/tools/perf/util/smt.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
diff --git a/tools/perf/util/smt.h b/tools/perf/util/smt.h
index b8414b7bcbc8..a98d65808f6a 100644
--- a/tools/perf/util/smt.h
+++ b/tools/perf/util/smt.h
@@ -1,6 +1,7 @@
-#ifndef SMT_H
-#define SMT_H 1
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __SMT_H
+#define __SMT_H 1
 
 int smt_on(void);
 
-#endif
+#endif /* __SMT_H */