diff --git a/tools/perf/util/python.c b/tools/perf/util/python.c
index b956868fd44503e1e1607f99f2e11c87c907e207..863b61478edd6d21533b925dde01abef35354a80 100644
--- a/tools/perf/util/python.c
+++ b/tools/perf/util/python.c
@@ -1004,8 +1004,10 @@ static PyObject *pyrf_evlist__read_on_cpu(struct pyrf_evlist *pevlist,
 			return PyErr_NoMemory();
 
 		evsel = perf_evlist__event2evsel(evlist, event);
-		if (!evsel)
+		if (!evsel) {
+			Py_INCREF(Py_None);
 			return Py_None;
+		}
 
 		pevent->evsel = evsel;