Date: Fri, 16 Jun 2017 10:50:20 -0700
From: Andi Kleen <ak@linux.intel.com>
To: Stephane Eranian <eranian@google.com>
Cc: LKML <linux-kernel@vger.kernel.org>,
        Arnaldo Carvalho de Melo <acme@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>, "mingo@elte.hu" <mingo@elte.hu>,
        "Liang, Kan" <kan.liang@intel.com>, Jiri Olsa <jolsa@redhat.com>
Subject: Re: [PATCH 0/5] perf: add support for capturing skid IP
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> > Yeah, I think it is easier and more portable, especially on hardware with a
> > PEBS-like mechanism but no branch buffer (like LBR). FYI, I did do a test
> > implementation yesterday to evaluate the difficulty.
> >
> A more generalized usage of the feature is to evaluate the amount of skid
> for any precise event.

It should be always the same (one instruction), except for the control flow
change case.

-Andi