6 static unsigned long flag = PERF_FLAG_FD_CLOEXEC;
8 static int perf_flag_probe(void)
10 /* use 'safest' configuration as used in perf_evsel__fallback() */
11 struct perf_event_attr attr = {
12 .type = PERF_TYPE_SOFTWARE,
13 .config = PERF_COUNT_SW_CPU_CLOCK,
19 /* check cloexec flag */
20 fd = sys_perf_event_open(&attr, 0, -1, -1,
21 PERF_FLAG_FD_CLOEXEC);
29 WARN_ONCE(err != EINVAL && err != EBUSY,
30 "perf_event_open(..., PERF_FLAG_FD_CLOEXEC) failed with unexpected error %d (%s)\n",
33 /* not supported, confirm error related to PERF_FLAG_FD_CLOEXEC */
34 fd = sys_perf_event_open(&attr, 0, -1, -1, 0);
37 if (WARN_ONCE(fd < 0 && err != EBUSY,
38 "perf_event_open(..., 0) failed unexpectedly with error %d (%s)\n",
47 unsigned long perf_event_open_cloexec_flag(void)
52 if (perf_flag_probe() <= 0)