Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1505103

Re: [PATCH v2 2/6] perf report: Caculate and return the branch counting in callchain

From Nilay Vaish <nilayvaish@gmail.com>
Newsgroups linux.kernel
Subject Re: [PATCH v2 2/6] perf report: Caculate and return the branch counting in callchain
Date 2016-10-20 19:10 +0200
Message-ID <sup0R-21Y-17@gated-at.bofh.it> (permalink)
References <su1UC-3KZ-23@gated-at.bofh.it> <su1UD-3KZ-47@gated-at.bofh.it> <suoHv-1G4-5@gated-at.bofh.it> <suoHw-1G4-15@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


On 20 October 2016 at 11:48, Andi Kleen <ak@linux.intel.com> wrote:
> On Thu, Oct 20, 2016 at 11:41:11AM -0500, Nilay Vaish wrote:
>> On 19 October 2016 at 17:01, Jin Yao <yao.jin@linux.intel.com> wrote:
>> > diff --git a/tools/perf/util/callchain.h b/tools/perf/util/callchain.h
>> > index 40ecf25..4f6bf6c 100644
>> > --- a/tools/perf/util/callchain.h
>> > +++ b/tools/perf/util/callchain.h
>> > @@ -115,6 +115,10 @@ struct callchain_list {
>> >                 bool            unfolded;
>> >                 bool            has_children;
>> >         };
>> > +       u64                     branch_count;
>> > +       u64                     predicted_count;
>> > +       u64                     abort_count;
>>
>> Can you explain what abort count is?  It seems you are referring to
>> miss-speculated branches.  If that is the case, I would prefer that we
>> replace abort by miss_speculated or miss_predicted.
>
> abort refers to TSX aborts. It has nothing to do with branch
> mispredictions.

OK, I am more confused now.  Are you predicting some quantity related
to transactions?  Why would you divide abort count by branch count?
Further, I just looked at patch 6/6.  It has the following text:

+ Also show with some branch flags that can be:
+ - Predicted: display the average percentage of predicated branches.
+     (predicated number / total number)
+ - Abort: display the average percentage of abort branches.
+ (abort number /total number)
+ - Cycles: cycles in basic block.


I think there is inconsistency between what you are suggesting and
what the patch has.

--
Nilay

Back to linux.kernel | Previous | NextPrevious in thread | Next in thread | Find similar | Unroll thread


Thread

[PATCH v2 2/6] perf report: Caculate and return the branch counting in callchain Jin Yao <yao.jin@linux.intel.com> - 2016-10-19 18:30 +0200
  Re: [PATCH v2 2/6] perf report: Caculate and return the branch  counting in callchain Nilay Vaish <nilayvaish@gmail.com> - 2016-10-20 18:50 +0200
    Re: [PATCH v2 2/6] perf report: Caculate and return the branch  counting in callchain Andi Kleen <ak@linux.intel.com> - 2016-10-20 18:50 +0200
      Re: [PATCH v2 2/6] perf report: Caculate and return the branch  counting in callchain Nilay Vaish <nilayvaish@gmail.com> - 2016-10-20 19:10 +0200
        Re: [PATCH v2 2/6] perf report: Caculate and return the branch  counting in callchain Andi Kleen <ak@linux.intel.com> - 2016-10-20 20:30 +0200
          Re: [PATCH v2 2/6] perf report: Caculate and return the branch  counting in callchain "Jin, Yao" <yao.jin@linux.intel.com> - 2016-10-21 02:30 +0200
            Re: [PATCH v2 2/6] perf report: Caculate and return the branch  counting in callchain Arnaldo Carvalho de Melo <acme@kernel.org> - 2016-10-25 20:20 +0200

csiph-web