From: Arnaldo Carvalho de Melo <[email protected]> We want to know when the fd went away, like when a monitored thread exits.
If we do not monitor such events, then the tools will wait forever on events from a vanished thread, like when running: $ sleep 5s & $ perf record -p `pidof sleep` This builds upon the kernel patch by Jiri Olsa that actually makes a poll on those file descriptors to return POLLHUP. It is also needed to change the tools to use perf_evlist__filter_pollfd() to check if there are remainings fds to monitor or if all are gone, in which case they will exit the poll/mmap/read loop. Acked-by: Jiri Olsa <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: David Ahern <[email protected]> Cc: Don Zickus <[email protected]> Cc: Frederic Weisbecker <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Mike Galbraith <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: Paul Mackerras <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Stephane Eranian <[email protected]> Link: http://lkml.kernel.org/n/[email protected] Signed-off-by: Arnaldo Carvalho de Melo <[email protected]> --- tools/perf/util/evlist.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c index 023bc3873ae9..502cd11ab17e 100644 --- a/tools/perf/util/evlist.c +++ b/tools/perf/util/evlist.c @@ -424,7 +424,7 @@ void perf_evlist__add_pollfd(struct perf_evlist *evlist, int fd) { fcntl(fd, F_SETFL, O_NONBLOCK); evlist->pollfd[evlist->nr_fds].fd = fd; - evlist->pollfd[evlist->nr_fds].events = POLLIN; + evlist->pollfd[evlist->nr_fds].events = POLLIN | POLLERR | POLLHUP; evlist->nr_fds++; } -- 1.9.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
