diff --git a/tools/perf/util/expr.l b/tools/perf/util/expr.l
index 74b9b59b1aa5..73db6a9ef97e 100644
--- a/tools/perf/util/expr.l
+++ b/tools/perf/util/expr.l
@@ -86,7 +86,7 @@ number		[0-9]+
 sch		[-,=]
 spec		\\{sch}
 sym		[0-9a-zA-Z_\.:@?]+
-symbol		{spec}*{sym}*{spec}*{sym}*{spec}*{sym}
+symbol		({spec}|{sym})+
 
 %%
 	struct expr_scanner_ctx *sctx = expr_get_extra(yyscanner);