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

[Jiri Olsa]

On Fri, Dec 11, 2015 at 04:12:24PM -0800, Andi Kleen wrote:
> From: Andi Kleen <ak@xxxxxxxxxxxxxxx>
> 
> [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@xxxxxxxxxxxxxxx>

Acked-by: Jiri Olsa <jolsa@xxxxxxxxxx>

thanks,
jirka
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