perf tools: Show per-event lost sample count (v2)

[PATCHSET 0/5] perf tools: Show per-event lost sample count (v2)

Posted by Namhyung Kim 3 years, 7 months ago

Hello,

Now we have PERF_FORMAT_LOST support, add it to perf record and report so that
it can show number of lost samples per event.  This can be useful if you want
to reconstruct number of events from the samples like when using -c option.

Changes in v2)
 * fix id_hdr_size calculation  (Adrian)
 * fix a memory leak
 * display lost samples even if no samples
 
 
Currently it adds PERF_RECORD_LOST_SAMPLES at the end of perf data after reading
event values by read(2).  The perf record unconditionally sets the lost bit if
the kernel supports it.  Users can see the number with `perf report --stat`.

You can get the code from 'perf/report-lost-v2' brach on

  git://git.kernel.org/pub/scm/linux/kernel/git/namhyung/linux-perf.git

Thanks,
Namhyung

Namhyung Kim (5):
  perf tools: Print LOST read format in the verbose mode
  perf record: Set PERF_FORMAT_LOST by default
  perf record: Read and inject LOST_SAMPLES events
  perf hist: Add nr_lost_samples to hist_stats
  perf report: Show per-event LOST SAMPLES stat

 tools/perf/builtin-record.c               | 64 +++++++++++++++++++++++
 tools/perf/builtin-report.c               | 17 ++++++
 tools/perf/util/events_stats.h            |  1 +
 tools/perf/util/evsel.c                   | 10 +++-
 tools/perf/util/evsel.h                   |  1 +
 tools/perf/util/hist.c                    | 15 ++++--
 tools/perf/util/hist.h                    |  1 +
 tools/perf/util/perf_event_attr_fprintf.c |  2 +-
 8 files changed, 106 insertions(+), 5 deletions(-)


base-commit: 6c3bd8d3e01d9014312caa52e4ef1c29d5249648
-- 
2.37.2.789.g6183377224-goog

Re: [PATCHSET 0/5] perf tools: Show per-event lost sample count (v2)

Posted by Adrian Hunter 3 years, 7 months ago

On 1/09/22 22:57, Namhyung Kim wrote:
> Hello,
> 
> Now we have PERF_FORMAT_LOST support, add it to perf record and report so that
> it can show number of lost samples per event.  This can be useful if you want
> to reconstruct number of events from the samples like when using -c option.
> 
> Changes in v2)
>  * fix id_hdr_size calculation  (Adrian)
>  * fix a memory leak
>  * display lost samples even if no samples
>  
>  
> Currently it adds PERF_RECORD_LOST_SAMPLES at the end of perf data after reading
> event values by read(2).  The perf record unconditionally sets the lost bit if
> the kernel supports it.  Users can see the number with `perf report --stat`.
> 
> You can get the code from 'perf/report-lost-v2' brach on
> 
>   git://git.kernel.org/pub/scm/linux/kernel/git/namhyung/linux-perf.git
> 
> Thanks,
> Namhyung
> 
> Namhyung Kim (5):
>   perf tools: Print LOST read format in the verbose mode
>   perf record: Set PERF_FORMAT_LOST by default
>   perf record: Read and inject LOST_SAMPLES events
>   perf hist: Add nr_lost_samples to hist_stats
>   perf report: Show per-event LOST SAMPLES stat

Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>

Re: [PATCHSET 0/5] perf tools: Show per-event lost sample count (v2)

Posted by Arnaldo Carvalho de Melo 3 years, 7 months ago

Em Fri, Sep 02, 2022 at 08:44:25PM +0300, Adrian Hunter escreveu:
> On 1/09/22 22:57, Namhyung Kim wrote:
> > Hello,
> > 
> > Now we have PERF_FORMAT_LOST support, add it to perf record and report so that
> > it can show number of lost samples per event.  This can be useful if you want
> > to reconstruct number of events from the samples like when using -c option.
> > 
> > Changes in v2)
> >  * fix id_hdr_size calculation  (Adrian)
> >  * fix a memory leak
> >  * display lost samples even if no samples
> >  
> >  
> > Currently it adds PERF_RECORD_LOST_SAMPLES at the end of perf data after reading
> > event values by read(2).  The perf record unconditionally sets the lost bit if
> > the kernel supports it.  Users can see the number with `perf report --stat`.
> > 
> > You can get the code from 'perf/report-lost-v2' brach on
> > 
> >   git://git.kernel.org/pub/scm/linux/kernel/git/namhyung/linux-perf.git
> > 
> > Thanks,
> > Namhyung
> > 
> > Namhyung Kim (5):
> >   perf tools: Print LOST read format in the verbose mode
> >   perf record: Set PERF_FORMAT_LOST by default
> >   perf record: Read and inject LOST_SAMPLES events
> >   perf hist: Add nr_lost_samples to hist_stats
> >   perf report: Show per-event LOST SAMPLES stat
> 
> Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>

Thanks, applied.

- Arnaldo