ftrace_set_clr_event
int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
extern int ftrace_set_clr_event(struct trace_array *tr, char *buf, int set);
if (ftrace_set_clr_event(tr, buf, 1) < 0)
ret = ftrace_set_clr_event(tr, parser.buffer + !set, set);
if (ftrace_set_clr_event(tr, token, 1))
ftrace_set_clr_event(tr, token, 0);