On Mon, Oct 02, 2017 at 09:48:31PM +0800, Jin, Yao wrote: > > > On 10/2/2017 9:00 PM, Jiri Olsa wrote: > > On Mon, Oct 02, 2017 at 08:52:59PM +0800, Jin, Yao wrote: > >> > >> > >> On 10/2/2017 7:50 PM, Jiri Olsa wrote: > >>> On Thu, Sep 28, 2017 at 08:45:16PM +0800, Jin Yao wrote: > >>> > >>> SNIP > >>> > >>>> + return ret; > >>>> + > >>>> + return do_write(ff, &evlist->last_sample_time, > >>>> + sizeof(evlist->last_sample_time)); > >>>> +} > >>>> + > >>>> static void print_hostname(struct feat_fd *ff, FILE *fp) > >>>> { > >>>> fprintf(fp, "# hostname : %s\n", ff->ph->env.hostname); > >>>> @@ -1506,6 +1520,19 @@ static void print_group_desc(struct feat_fd *ff, > >>>> FILE *fp) > >>>> } > >>>> } > >>>> > >>>> +static void print_sample_time(struct feat_fd *ff, FILE *fp) > >>>> +{ > >>>> + struct perf_session *session; > >>>> + > >>>> + session = container_of(ff->ph, struct perf_session, header); > >>>> + > >>>> + fprintf(fp, "# time of first sample : %" PRIu64 "\n", > >>>> + session->evlist->first_sample_time); > >>>> + > >>>> + fprintf(fp, "# time of last sample : %" PRIu64 "\n", > >>>> + session->evlist->last_sample_time); > >>> > >>> this could be done in some follow up patch, but could we > >>> display this in some human readable way.. > >>> > >>> # time of first sample : 218077073264620 > >>> # time of last sample : 218077073395488 > >>> > >>> jirka > >>> > >> > >> Could I add the printing of duration? For example, > >> > >> duration = (double)(last_sample_time - first_sample_time) / NSEC_PER_MSEC; > >> fprintf(fp, "# sample duration: %10.3f (ms)\n", duration); > >> > >> fprintf(fp, "# time of first sample : %" PRIu64 "\n", > >> first_sample_time); > >> > >> fprintf(fp, "# time of last sample : %" PRIu64 "\n", > >> last_sample_time); > > > > could be, but mainly please display the time same way the perf script does: > > > > 218482.819815 > > > > jirka > > > > Fine. I think I can use timestamp__scnprintf_usec() to print the timestamp. > > BTW, do we need the duration printing here?
yea, might be helpful thanks, jirka