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

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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,
jirka
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[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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