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Re: [PATCH 2/3] perf tools: Add callchain order support for libunwind DWARF unwinder

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On Wed, Nov 18, 2015 at 08:54:31AM +0100, Jiri Olsa wrote:
> On Wed, Nov 18, 2015 at 12:13:08PM +0800, Wangnan (F) wrote:
> 
> SNIP
> 
> >      3.38%  a.out    a.out             [.] funcc
> >               |
> >               ---funcc
> >                  |
> >                  |--2.70%-- funcb
> >                  |          funca
> >                  |          main
> >                  |          __libc_start_main
> >                  |          _start
> >                  |
> >                   --0.68%-- 0
> > 
> > 
> > I'm not sure whether we can regard this behavior changing as a bugfix? I
> > think
> > there may be some reason the original code explicitly avoid creating an '0'
> > entry.
> > 
> > Then I tried to find why perf can't get call frame on my case, and
> > I guess there's something wrong whe dealing with 'call' command, because
> > the instruction on it I can't get callchain from libunwind is a 'callq':
> > 
> >   ...
> >   4005bf:       be 00 00 00 00          mov    $0x0,%esi
> >   4005c4:       48 89 c7                mov    %rax,%rdi
> >   4005c7:       e8 74 fe ff ff          callq  400440 <gettimeofday@plt>
> >                 us2 = tv2.tv_sec * 1000000 + tv2.tv_usec;
> >   4005cc:       48 8b 04 24             mov    (%rsp),%rax
> >   ...
> > 
> > But this is another problem, we can discuss it in a new thread.
> 
> so the problem is you dont see the gettimeofday call at the end?
> 
> could you share the test code?

just saw your other email on this issue.. let's continue there

jirka
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[PATCH 2/3] perf tools: Add callchain order support for libunwind DWARF unwinder Jiri Olsa <jolsa@kernel.org> - 2015-11-17 16:10 +0100
  Re: [PATCH 2/3] perf tools: Add callchain order support for libunwind  DWARF unwinder "Wangnan (F)" <wangnan0@huawei.com> - 2015-11-18 05:20 +0100
    Re: [PATCH 2/3] perf tools: Add callchain order support for  libunwind DWARF unwinder Namhyung Kim <namhyung@kernel.org> - 2015-11-18 06:50 +0100
      Re: [PATCH 2/3] perf tools: Add callchain order support for libunwind  DWARF unwinder "Wangnan (F)" <wangnan0@huawei.com> - 2015-11-18 08:40 +0100
        Re: [PATCH 2/3] perf tools: Add callchain order support for  libunwind DWARF unwinder Namhyung Kim <namhyung@kernel.org> - 2015-11-22 16:30 +0100
      Re: [PATCH 2/3] perf tools: Add callchain order support for  libunwind DWARF unwinder Jiri Olsa <jolsa@redhat.com> - 2015-11-18 09:30 +0100
      Re: [PATCH 2/3] perf tools: Add callchain order support for  libunwind DWARF unwinder Jiri Olsa <jolsa@redhat.com> - 2015-11-18 09:30 +0100
        Re: [PATCH 2/3] perf tools: Add callchain order support for libunwind DWARF unwinder Namhyung Kim <namhyung@gmail.com> - 2015-11-18 10:30 +0100
    Re: [PATCH 2/3] perf tools: Add callchain order support for  libunwind DWARF unwinder Jiri Olsa <jolsa@redhat.com> - 2015-11-18 09:00 +0100
      Re: [PATCH 2/3] perf tools: Add callchain order support for libunwind  DWARF unwinder "Wangnan (F)" <wangnan0@huawei.com> - 2015-11-18 09:10 +0100
      Re: [PATCH 2/3] perf tools: Add callchain order support for  libunwind DWARF unwinder Jiri Olsa <jolsa@redhat.com> - 2015-11-18 09:20 +0100
    [PATCHv2 2/3] perf tools: Add callchain order support for libunwind  DWARF unwinder Jiri Olsa <jolsa@redhat.com> - 2015-11-18 09:00 +0100
      Re: [PATCHv2 2/3] perf tools: Add callchain order support for libunwind  DWARF unwinder "Wangnan (F)" <wangnan0@huawei.com> - 2015-11-18 10:50 +0100
      [tip:perf/core] perf callchain:   Add order support for libunwind DWARF unwinder tip-bot for Jiri Olsa <tipbot@zytor.com> - 2015-11-26 09:20 +0100

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