Commit 033fa713 authored Sep 08, 2014 by Arnaldo Carvalho de Melo

perf evlist: We need to poll all event file descriptors

Because we want to notice when they get POLLHUP'ed, so that we can
figure out when all threads exited in a workload being monitored.

We can't just monitor the fds that were mmaped, we need to notice when
all the fds that were PERF_EVENT_IOC_SET_OUTPUT'ed too, because the mmap
stays even after the fd that originally was used to do the mmap call
went away, its only when all the set-output fds for a mmap are gone that
the mmap is.

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/r/20140908151016.GH17728@krava.brq.redhat.com
Link: http://lkml.kernel.org/n/tip-24omlq5asrfg4uo3muuzn2bl@git.kernel.org


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

parent 8179672c

tools/perf/util/evlist.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -717,8 +717,6 @@ static int __perf_evlist__mmap(struct perf_evlist *evlist, int idx,
		evlist->mmap[idx].base = NULL;
		return -1;
		}

		perf_evlist__add_pollfd(evlist, fd);
		return 0;
		}

		@@ -745,6 +743,8 @@ static int perf_evlist__mmap_per_evsel(struct perf_evlist *evlist, int idx,
		return -1;
		}

		perf_evlist__add_pollfd(evlist, fd);

		if ((evsel->attr.read_format & PERF_FORMAT_ID) &&
		perf_evlist__id_add_fd(evlist, evsel, cpu, thread, fd) < 0)
		return -1;