From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752259AbaHVVCV (ORCPT ); Fri, 22 Aug 2014 17:02:21 -0400 Received: from mail.kernel.org ([198.145.19.201]:43324 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752018AbaHVVAP (ORCPT ); Fri, 22 Aug 2014 17:00:15 -0400 From: Arnaldo Carvalho de Melo To: Jiri Olsa Cc: linux-kernel@vger.kernel.org, Arnaldo Carvalho de Melo , Adrian Hunter , David Ahern , Don Zickus , Frederic Weisbecker , Ingo Molnar , Mike Galbraith , Namhyung Kim , Paul Mackerras , Peter Zijlstra , Stephane Eranian Subject: [PATCH 03/10] perf evlist: Monitor POLLERR and POLLHUP events too Date: Fri, 22 Aug 2014 17:59:43 -0300 Message-Id: <1408741190-5123-4-git-send-email-acme@kernel.org> X-Mailer: git-send-email 1.9.3 In-Reply-To: <1408741190-5123-1-git-send-email-acme@kernel.org> References: <1408741190-5123-1-git-send-email-acme@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Arnaldo Carvalho de Melo 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. Cc: Adrian Hunter Cc: David Ahern Cc: Don Zickus Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Jiri Olsa Cc: Mike Galbraith Cc: Namhyung Kim Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/n/tip-a4fslwspov0bs69nj825hqpq@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- 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 bd7896073d10..cddc700d718f 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