diff --git a/tools/perf/util/string.c b/tools/perf/util/string.c
index c93eca9..04743d3 100644
--- a/tools/perf/util/string.c
+++ b/tools/perf/util/string.c
@@ -1,3 +1,4 @@
+#include <string.h>
 #include "string.h"
 
 static int hex(char ch)
@@ -32,3 +33,13 @@
 
 	return p - ptr;
 }
+
+char *strxfrchar(char *s, char from, char to)
+{
+	char *p = s;
+
+	while ((p = strchr(p, from)) != NULL)
+		*p++ = to;
+
+	return s;
+}