perf trace: Filter out POLLHUP'ed file descriptors

So that we don't continue polling on vanished file descriptors, i.e.
file descriptors for events monitoring threads that exited.

I.e. the following 'trace' command now exits as expected, instead
of staying in an eternal loop:

      $ sleep 5s &
      $ trace -p `pidof sleep`

Reported-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-6qegv786zbf6i8us6t4rxug9@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Arnaldo Carvalho de Melo 2014-09-22 14:39:48 -03:00
parent 6dcf45ef98
commit 46fb3c21d2
1 changed files with 6 additions and 1 deletions

View File

@ -2044,6 +2044,7 @@ static int trace__run(struct trace *trace, int argc, const char **argv)
int err = -1, i;
unsigned long before;
const bool forks = argc > 0;
bool draining = false;
char sbuf[STRERR_BUFSIZE];
trace->live = true;
@ -2171,8 +2172,12 @@ next_event:
if (trace->nr_events == before) {
int timeout = done ? 100 : -1;
if (perf_evlist__poll(evlist, timeout) > 0)
if (!draining && perf_evlist__poll(evlist, timeout) > 0) {
if (perf_evlist__filter_pollfd(evlist, POLLERR | POLLHUP) == 0)
draining = true;
goto again;
}
} else {
goto again;
}