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

From: Jiri Olsa
Date: Mon Jul 03 2017 - 03:58:49 EST

On Fri, Jun 30, 2017 at 10:16:56AM -0400, kan.liang@xxxxxxxxx wrote:
> From: Kan Liang <kan.liang@xxxxxxxxx>
> 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@xxxxxxxxx>

for the patchset:

Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx>