Hi Andi, On Tue, 7 Jan 2014 14:14:07 -0800, Andi Kleen wrote: > From: Andi Kleen <[email protected]> > > perf stat has a --delay option to delay measuring the workload. > This is useful to skip measuring the startup phase of the program, which > is often very different from the main workload. > > The same is useful for perf record when sampling. Add --delay to perf record > too. > -D was already taken for record, so there is only a long option. > > Signed-off-by: Andi Kleen <[email protected]> > --- > tools/perf/Documentation/perf-record.txt | 4 ++++ > tools/perf/builtin-record.c | 9 ++++++++- > tools/perf/perf.h | 1 + > tools/perf/util/evsel.c | 5 +++-- > 4 files changed, 16 insertions(+), 3 deletions(-) > > diff --git a/tools/perf/Documentation/perf-record.txt > b/tools/perf/Documentation/perf-record.txt > index 43b42c4..e349151 100644 > --- a/tools/perf/Documentation/perf-record.txt > +++ b/tools/perf/Documentation/perf-record.txt > @@ -207,6 +207,10 @@ Force the use of per-cpu mmaps. By default, when tasks > are specified (i.e. -p, > forces per-cpu mmaps. A side-effect of that is that inheritance is > automatically enabled. Add the -i option also to disable inheritance. > > +--delay msecs:: > +After starting the program, wait msecs before measuring. This is useful to > +filter out the startup phase of the program, which is often very different. > + > SEE ALSO > -------- > linkperf:perf-stat[1], linkperf:perf-list[1] > diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c > index 7c8020a..110158e 100644 > --- a/tools/perf/builtin-record.c > +++ b/tools/perf/builtin-record.c > @@ -506,7 +506,7 @@ static int __cmd_record(struct perf_record *rec, int > argc, const char **argv) > * (apart from group members) have enable_on_exec=1 set, > * so don't spoil it by prematurely enabling them. > */ > - if (!target__none(&opts->target)) > + if (!target__none(&opts->target) && !opts->initial_delay) > perf_evlist__enable(evsel_list); > > /* > @@ -515,6 +515,11 @@ static int __cmd_record(struct perf_record *rec, int > argc, const char **argv) > if (forks) > perf_evlist__start_workload(evsel_list); > > + if (opts->initial_delay) { > + usleep(opts->initial_delay * 1000); > + perf_evlist__enable(evsel_list); > + } > + > for (;;) { > int hits = rec->samples; > > @@ -890,6 +895,8 @@ const struct option record_options[] = { > "sample transaction flags (special events only)"), > OPT_BOOLEAN(0, "force-per-cpu", &record.opts.target.force_per_cpu, > "force the use of per-cpu mmaps"), > + OPT_UINTEGER(0, "delay", &record.opts.initial_delay, > + "ms to wait before starting measurement after program start"), > OPT_END() > }; > > diff --git a/tools/perf/perf.h b/tools/perf/perf.h > index b079304..d052f1d 100644 > --- a/tools/perf/perf.h > +++ b/tools/perf/perf.h > @@ -268,6 +268,7 @@ struct perf_record_opts { > u64 user_interval; > u16 stack_dump_size; > bool sample_transaction; > + unsigned initial_delay; > }; > > #endif > diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c > index 46dd4c2..4a70656 100644 > --- a/tools/perf/util/evsel.c > +++ b/tools/perf/util/evsel.c > @@ -689,14 +689,15 @@ void perf_evsel__config(struct perf_evsel *evsel, > * Disabling only independent events or group leaders, > * keeping group members enabled. > */ > - if (perf_evsel__is_group_leader(evsel)) > + if (perf_evsel__is_group_leader(evsel) || opts->initial_delay) > attr->disabled = 1;
It seems this hunk is not needed since it'll disable group member events which is not what we want. Note that the perf_evlist__enable/disable() only work for the leaders. Thanks, Namhyung > > /* > * Setting enable_on_exec for independent events and > * group leaders for traced executed by perf. > */ > - if (target__none(&opts->target) && perf_evsel__is_group_leader(evsel)) > + if (target__none(&opts->target) && perf_evsel__is_group_leader(evsel) && > + !opts->initial_delay) > attr->enable_on_exec = 1; > } -- 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/
