8 static unsigned long flag = PERF_FLAG_FD_CLOEXEC;
10 static int perf_flag_probe(void)
12 /* use 'safest' configuration as used in perf_evsel__fallback() */
13 struct perf_event_attr attr = {
14 .type = PERF_TYPE_SOFTWARE,
15 .config = PERF_COUNT_SW_CPU_CLOCK,
22 char sbuf[STRERR_BUFSIZE];
29 /* check cloexec flag */
30 fd = sys_perf_event_open(&attr, pid, cpu, -1,
31 PERF_FLAG_FD_CLOEXEC);
32 if (fd < 0 && pid == -1 && errno == EACCES) {
45 WARN_ONCE(err != EINVAL && err != EBUSY,
46 "perf_event_open(..., PERF_FLAG_FD_CLOEXEC) failed with unexpected error %d (%s)\n",
47 err, strerror_r(err, sbuf, sizeof(sbuf)));
49 /* not supported, confirm error related to PERF_FLAG_FD_CLOEXEC */
50 fd = sys_perf_event_open(&attr, pid, cpu, -1, 0);
53 if (WARN_ONCE(fd < 0 && err != EBUSY,
54 "perf_event_open(..., 0) failed unexpectedly with error %d (%s)\n",
55 err, strerror_r(err, sbuf, sizeof(sbuf))))
63 unsigned long perf_event_open_cloexec_flag(void)
68 if (perf_flag_probe() <= 0)