Re: [PATCH 1/2] perf intel-pt: Fix estimated timestamps for cycle-accurate mode

From: Arnaldo Carvalho de Melo
Date: Wed Oct 05 2016 - 07:17:49 EST


Em Wed, Oct 05, 2016 at 10:33:14AM +0300, Adrian Hunter escreveu:
> On 28/09/16 14:41, Adrian Hunter wrote:
> > In cycle-accurate mode, timestamps can be calculated from CYC packets. The
> > decoder also estimates timestamps based on the number of instructions since
> > the last timestamp. For that to work in cycle-accurate mode, the
> > instruction count needs to be reset to zero when a timestamp is calculated
> > from a CYC packet, but that wasn't happening, so fix it.
> >
> > Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
> > Cc: stable@xxxxxxxxxxxxxxx # v4.3+
>
> Hi
>
> These 2 patches are still outstanding when you have time.

Thanks for the reminder, applied.

> Regards
> Adrian
>
> > ---
> > tools/perf/util/intel-pt-decoder/intel-pt-decoder.c | 2 ++
> > 1 file changed, 2 insertions(+)
> >
> > diff --git a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
> > index 7591a0c37473..3d1d446f037f 100644
> > --- a/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
> > +++ b/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
> > @@ -1353,6 +1353,8 @@ static void intel_pt_calc_cyc_timestamp(struct intel_pt_decoder *decoder)
> > timestamp, decoder->timestamp);
> > else
> > decoder->timestamp = timestamp;
> > +
> > + decoder->timestamp_insn_cnt = 0;
> > }
> >
> > /* Walk PSB+ packets when already in sync. */
> >