typedef int (*event_op2)(struct perf_session *session, union perf_event *event);
typedef s64 (*event_op3)(struct perf_session *session, union perf_event *event);
-typedef int (*event_op4)(struct perf_session *session, union perf_event *event, u64 data);
+typedef int (*event_op4)(struct perf_session *session, union perf_event *event, u64 data,
+ const char *str);
typedef int (*event_oe)(struct perf_tool *tool, union perf_event *event,
struct ordered_events *oe);