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

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Date:   Wed, 5 Oct 2016 08:16:36 -0300
From:   Arnaldo Carvalho de Melo <acme@...nel.org>
To:     Adrian Hunter <adrian.hunter@...el.com>
Cc:     Jiri Olsa <jolsa@...hat.com>, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 1/2] perf intel-pt: Fix estimated timestamps for
 cycle-accurate mode

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@...el.com>
> > Cc: stable@...r.kernel.org # 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. */
> >