Re: [PATCH V2 2/2] perf tools: always set no branch for dummy event in PT

From	Jiri Olsa <jolsa@redhat.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH V2 2/2] perf tools: always set no branch for dummy event in PT
Date	2017-07-03 10:00 +0200
Message-ID	<tZ4r0-6vk-13@gated-at.bofh.it> (permalink)
References	<tY4W5-6wZ-7@gated-at.bofh.it> <tY4W7-6wZ-43@gated-at.bofh.it>
Organization	linux.* mail to news gateway

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On Fri, Jun 30, 2017 at 10:16:56AM -0400, kan.liang@intel.com wrote:
> From: Kan Liang <kan.liang@intel.com>
> 
> An earlier kernel patch allowed enabling PT and LBR at the same time on
> Goldmont.
> 
> commit ccbebba4c6bf ("perf/x86/intel/pt: Bypass PT vs. LBR exclusivity
> if the core supports it")
> 
> However, users still cannot use Intel PT and LBRs simultaneously.
>  $ sudo perf record -e cycles,intel_pt//u -b  -- sleep 1
>  Error:
>  PMU Hardware doesn't support sampling/overflow-interrupts.
> 
> PT implicitly adds dummy event in perf tool. dummy event is software
> event which doesn't support LBR.
> 
> Always setting no branch for dummy event in Intel PT.
> 
> Signed-off-by: Kan Liang <kan.liang@intel.com>

for the patchset:

Acked-by: Jiri Olsa <jolsa@kernel.org>

thanks,
jirka

Thread

[PATCH V2 1/2] perf tools: set no_aux_samples for the tracking event in PT kan.liang@intel.com - 2017-06-30 16:20 +0200
  [PATCH V2 2/2] perf tools: always set no branch for dummy event in PT kan.liang@intel.com - 2017-06-30 16:20 +0200
    Re: [PATCH V2 2/2] perf tools: always set no branch for dummy event  in PT Jiri Olsa <jolsa@redhat.com> - 2017-07-03 10:00 +0200
      Re: [PATCH V2 2/2] perf tools: always set no branch for dummy event  in PT Arnaldo Carvalho de Melo <acme@kernel.org> - 2017-07-03 19:00 +0200

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