Path: csiph.com!feeder.erje.net!1.us.feeder.erje.net!newsfeed.fsmpi.rwth-aachen.de!newsfeed.straub-nv.de!news.unit0.net!news.panservice.it!news.spin.it!bofh.it!news.nic.it!robomod From: Wang Nan Newsgroups: linux.kernel Subject: [PATCH v12 7/8] perf tools: Don't warn about out of order event if write_backward is used Date: Fri, 01 Jul 2016 04:30:01 +0200 Message-ID: References: X-Mailer: git-send-email 1.8.3.4 MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.107.193.248] X-Cfilter-Loop: Reflected X-Mirapoint-Virus-Rapid-Raw: score=unknown(0), refid=str=0001.0A020203.5775D44B.0075,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=0.0.0.0, so=2013-06-18 04:22:30, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-ID: 1dbfe1607146ac1286c2a927b2111219 Sender: robomod@news.nic.it List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Approved: robomod@news.nic.it Lines: 88 Organization: linux.* mail to news gateway X-Original-Cc: , , , Wang Nan , He Kuang , "Arnaldo Carvalho de Melo" , Jiri Olsa , "Masami Hiramatsu" , Namhyung Kim , "Nilay Vaish" X-Original-Date: Fri, 1 Jul 2016 02:23:50 +0000 X-Original-Message-ID: <1467339831-171169-8-git-send-email-wangnan0@huawei.com> X-Original-References: <1467339831-171169-1-git-send-email-wangnan0@huawei.com> X-Original-Sender: linux-kernel-owner@vger.kernel.org Xref: csiph.com linux.kernel:1434972 If write_backward attribute is set, records are written into kernel ring buffer from end to beginning, but read from beginning to end. To avoid 'XX out of order events recorded' warning message (timestamps of records is in reverse order when using write_backward), suppress the warning message if write_backward is selected by at lease one event. Result: Before this patch: # perf record -m 1 -e raw_syscalls:sys_exit/overwrite/ \ -e raw_syscalls:sys_enter \ dd if=/dev/zero of=/dev/null count=300 300+0 records in 300+0 records out 153600 bytes (154 kB) copied, 0.000601617 s, 255 MB/s [ perf record: Woken up 5 times to write data ] Warning: 40 out of order events recorded. [ perf record: Captured and wrote 0.096 MB perf.data (696 samples) ] After this patch: # perf record -m 1 -e raw_syscalls:sys_exit/overwrite/ \ -e raw_syscalls:sys_enter \ dd if=/dev/zero of=/dev/null count=300 300+0 records in 300+0 records out 153600 bytes (154 kB) copied, 0.000644873 s, 238 MB/s [ perf record: Woken up 5 times to write data ] [ perf record: Captured and wrote 0.096 MB perf.data (696 samples) ] Signed-off-by: Wang Nan Signed-off-by: He Kuang Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: Zefan Li Cc: Nilay Vaish Cc: pi3orama@163.com --- tools/perf/util/session.c | 22 +++++++++++++++++++--- 1 file changed, 19 insertions(+), 3 deletions(-) diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c index 078d496..5d61242 100644 --- a/tools/perf/util/session.c +++ b/tools/perf/util/session.c @@ -1499,10 +1499,27 @@ int perf_session__register_idle_thread(struct perf_session *session) return err; } +static void +perf_session__warn_order(const struct perf_session *session) +{ + const struct ordered_events *oe = &session->ordered_events; + struct perf_evsel *evsel; + bool should_warn = true; + + evlist__for_each_entry(session->evlist, evsel) { + if (evsel->attr.write_backward) + should_warn = false; + } + + if (!should_warn) + return; + if (oe->nr_unordered_events != 0) + ui__warning("%u out of order events recorded.\n", oe->nr_unordered_events); +} + static void perf_session__warn_about_errors(const struct perf_session *session) { const struct events_stats *stats = &session->evlist->stats; - const struct ordered_events *oe = &session->ordered_events; if (session->tool->lost == perf_event__process_lost && stats->nr_events[PERF_RECORD_LOST] != 0) { @@ -1559,8 +1576,7 @@ static void perf_session__warn_about_errors(const struct perf_session *session) stats->nr_unprocessable_samples); } - if (oe->nr_unordered_events != 0) - ui__warning("%u out of order events recorded.\n", oe->nr_unordered_events); + perf_session__warn_order(session); events_stats__auxtrace_error_warn(stats); -- 1.8.3.4