From cb24d01d217497fb32467de22d773655f47d3896 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Wed, 22 Apr 2015 10:04:23 -0300 Subject: perf trace: Enable events when doing system wide tracing and starting a workload commit f7aa222ff397 Author: Arnaldo Carvalho de Melo Date: Tue Feb 3 13:25:39 2015 -0300 perf trace: No need to enable evsels for workload started from perf The assumption was that whenever a workload is specified, the attr.enable_on_exec evsel flag would be set, but that is not happening when perf_record_opts.system_wide is set, for instance That resulted in both perf_evlist__enable() and attr.enable_on_exec being not called/set, which made the events to remain disabled while the workload runs, producing no output. Fix it, by calling perf_evlist__enable() in the 'trace' tool when forking and not targetting a workload started from trace v2: Test against !target__none(), as suggested by Namhyung Kim, that is what is used in perf_evsel__config() when deciding if the attr.enable_on_exec flag to be set. More work is needed to cover other cases such as opts->initial_delay. Acked-by: Jiri Olsa Cc: Adrian Hunter Cc: Borislav Petkov Cc: David Ahern Cc: Don Zickus Cc: Frederic Weisbecker Cc: Namhyung Kim Cc: Stephane Eranian Link: http://lkml.kernel.org/n/tip-27z7169pvfxgj8upic636syv@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-trace.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'tools/perf/builtin-trace.c') diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c index e124741be187..8842218e1856 100644 --- a/tools/perf/builtin-trace.c +++ b/tools/perf/builtin-trace.c @@ -2241,10 +2241,11 @@ static int trace__run(struct trace *trace, int argc, const char **argv) if (err < 0) goto out_error_mmap; + if (!target__none(&trace->opts.target)) + perf_evlist__enable(evlist); + if (forks) perf_evlist__start_workload(evlist); - else - perf_evlist__enable(evlist); trace->multiple_threads = evlist->threads->map[0] == -1 || evlist->threads->nr > 1 || -- cgit v1.2.1 From 02ac5421ddc634767c732f9b6a10a395a9ecfc4f Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Wed, 22 Apr 2015 11:11:57 -0300 Subject: perf trace: Disable events and drain events when forked workload ends We were not checking in the inner event processing loop if the forked workload had finished, which, on a busy system, may make it take a long time trying to drain events, entering a seemingly neverending loop, waiting for the system to get idle enough to make it drain the buffers. Fix it by disabling the events when 'done' is true, in the inner loop, to start draining what is in the buffers. Now: [root@ssdandy ~]# time trace --filter-pids 14003 -a sleep 1 | tail 996.748 ( 0.002 ms): sh/30296 rt_sigprocmask(how: SETMASK, nset: 0x7ffc83418160, sigsetsize: 8) = 0 996.751 ( 0.002 ms): sh/30296 rt_sigprocmask(how: BLOCK, nset: 0x7ffc834181f0, oset: 0x7ffc83418270, sigsetsize: 8) = 0 996.755 ( 0.002 ms): sh/30296 rt_sigaction(sig: INT, act: 0x7ffc83417f50, oact: 0x7ffc83417ff0, sigsetsize: 8) = 0 1004.543 ( 0.362 ms): tail/30198 ... [continued]: read()) = 4096 1004.548 ( 7.791 ms): sh/30296 wait4(upid: -1, stat_addr: 0x7ffc834181a0) ... 1004.975 ( 0.427 ms): tail/30198 read(buf: 0x7633f0, count: 8192) = 4096 1005.390 ( 0.410 ms): tail/30198 read(buf: 0x765410, count: 8192) = 4096 1005.743 ( 0.348 ms): tail/30198 read(buf: 0x7633f0, count: 8192) = 4096 1006.197 ( 0.449 ms): tail/30198 read(buf: 0x765410, count: 8192) = 4096 1006.492 ( 0.290 ms): tail/30198 read(buf: 0x7633f0, count: 8192) = 4096 real 0m1.219s user 0m0.704s sys 0m0.331s [root@ssdandy ~]# Reported-by: Michael Petlan Suggested-by: Jiri Olsa Acked-by: Jiri Olsa Cc: Adrian Hunter Cc: Borislav Petkov Cc: David Ahern Cc: Don Zickus Cc: Frederic Weisbecker Cc: Namhyung Kim Cc: Stephane Eranian Link: http://lkml.kernel.org/n/tip-p6kpn1b26qcbe47pufpw0tex@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-trace.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'tools/perf/builtin-trace.c') diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c index 8842218e1856..e122970361f2 100644 --- a/tools/perf/builtin-trace.c +++ b/tools/perf/builtin-trace.c @@ -2273,6 +2273,11 @@ next_event: if (interrupted) goto out_disable; + + if (done && !draining) { + perf_evlist__disable(evlist); + draining = true; + } } } -- cgit v1.2.1