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Re: [PATCH] perf, tools: Disable branch flags/cycles for --callgraph lbr

From Arnaldo Carvalho de Melo <acme@kernel.org>
Newsgroups linux.kernel
Subject Re: [PATCH] perf, tools: Disable branch flags/cycles for --callgraph lbr
Date 2015-12-14 16:20 +0100
Message-ID <qFD4S-7Rv-27@gated-at.bofh.it> (permalink)
References <qEG4N-3aW-3@gated-at.bofh.it> <qFy5c-4ms-1@gated-at.bofh.it>
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Em Mon, Dec 14, 2015 at 10:55:38AM +0100, Jiri Olsa escreveu:
> On Fri, Dec 11, 2015 at 04:12:24PM -0800, Andi Kleen wrote:
> > From: Andi Kleen <ak@linux.intel.com>
> > 
> > [The kernel patch needed for this is in tip now
> > (b16a5b52eb9 perf/x86: Add option to disable ...)
> > So this user tools patch to make use of it should be merged now]
> > 
> > Automatically disable collecting branch flags and cycles with
> > --call-graph lbr. This allows avoiding a bunch of extra MSR
> > reads in the PMI on Skylake.
> > 
> > When the kernel doesn't support the new flags they are automatically
> > cleared in the fallback code.
> > 
> > v2: Switch to use branch_sample_type instead of sample_type.
> > Adjust description.
> > Fix the fallback logic.
> > Signed-off-by: Andi Kleen <ak@linux.intel.com>
> 
> Acked-by: Jiri Olsa <jolsa@kernel.org>

Thanks, applied to perf/core.

- Arnaldo
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Thread

[PATCH] perf, tools: Disable branch flags/cycles for --callgraph lbr Andi Kleen <andi@firstfloor.org> - 2015-12-12 01:20 +0100
  Re: [PATCH] perf, tools: Disable branch flags/cycles for --callgraph  lbr Jiri Olsa <jolsa@redhat.com> - 2015-12-14 11:00 +0100
    Re: [PATCH] perf, tools: Disable branch flags/cycles for --callgraph  lbr Arnaldo Carvalho de Melo <acme@kernel.org> - 2015-12-14 16:20 +0100
  [tip:perf/core] perf evsel: Disable branch flags/  cycles for --callgraph lbr tip-bot for Andi Kleen <tipbot@zytor.com> - 2015-12-18 09:50 +0100

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