In case of failure, unrelated to PERF_FLAG_FD_CLOEXEC, perf_flag_probe() reports the error twice. For example:
$ perf record ls Error: perf_event_open(..., PERF_FLAG_FD_CLOEXEC) failed with unexpected error 16 (Device or resource busy) perf_event_open(..., 0) failed unexpectedly with error 16 (Device or resource busy) The PMU counters are busy/taken by another profiler. We found oprofile daemon running, please stop it and try again. This patch changes the function to only report a second error message when the two calls to perf_even_open(2) fail with different error codes. Cc: Andi Kleen <a...@linux.intel.com> Cc: Arnaldo Carvalho de Melo <a...@kernel.org> Cc: Ingo Molnar <mi...@redhat.com> Cc: Jiri Olsa <jo...@kernel.org> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Paul Mackerras <pau...@samba.org> Cc: Adrian Hunter <adrian.hun...@intel.com> Cc: David Ahern <dsah...@gmail.com> Cc: Frederic Weisbecker <fweis...@gmail.com> Cc: Namhyung Kim <namhy...@gmail.com> Cc: Stephane Eranian <eran...@google.com> Cc: William Cohen <wco...@redhat.com> Link: http://lkml.kernel.org/r/1406908014-8312-1-git-send-email-jo...@kernel.org Reported-by: Jiri Olsa <jo...@kernel.org> Signed-off-by: Yann Droneaud <ydrone...@opteya.com> --- tools/perf/util/cloexec.c | 24 +++++++++++++----------- 1 file changed, 13 insertions(+), 11 deletions(-) diff --git a/tools/perf/util/cloexec.c b/tools/perf/util/cloexec.c index c5d05ec17220..dc360ebde745 100644 --- a/tools/perf/util/cloexec.c +++ b/tools/perf/util/cloexec.c @@ -13,34 +13,36 @@ static int perf_flag_probe(void) .config = PERF_COUNT_SW_CPU_CLOCK, }; int fd; - int err; + int err0, err1; /* check cloexec flag */ fd = sys_perf_event_open(&attr, 0, -1, -1, PERF_FLAG_FD_CLOEXEC); - err = errno; + err0 = errno; if (fd >= 0) { close(fd); return 1; } - WARN_ONCE(err != EINVAL, + WARN_ONCE(err0 != EINVAL, "perf_event_open(..., PERF_FLAG_FD_CLOEXEC) failed with unexpected error %d (%s)\n", - err, strerror(err)); + err0, strerror(err0)); /* not supported, confirm error related to PERF_FLAG_FD_CLOEXEC */ fd = sys_perf_event_open(&attr, 0, -1, -1, 0); - err = errno; + err1 = errno; - if (WARN_ONCE(fd < 0, - "perf_event_open(..., 0) failed unexpectedly with error %d (%s)\n", - err, strerror(err))) - return -1; + if (fd >= 0) { + close(fd); + return 0; + } - close(fd); + WARN_ONCE(err0 != err1, + "perf_event_open(..., 0) failed unexpectedly with error %d (%s)\n", + err1, strerror(err1)); - return 0; + return -1; } unsigned long perf_event_open_cloexec_flag(void) -- 1.9.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
