Re: [PATCH 1/2] perf evsel: Fix probing of precise_ip level for default cycles event

[Arnaldo Carvalho de Melo <acme@kernel.org>]

Em Wed, Jun 14, 2017 at 07:45:01AM +0200, Ingo Molnar escreveu:
>  triton:~/tip> perf report --stdio
>  unwind: target platform=x86 is not supported
>  unwind: target platform=x86 is not supported
>  unwind: target platform=x86 is not supported
>  unwind: target platform=x86 is not supported
>  unwind: target platform=x86 is not supported
>  unwind: target platform=x86 is not supported
>  unwind: target platform=x86 is not supported
>  unwind: target platform=x86 is not supported

> # ========
> # captured on: Wed Jun 14 07:34:42 2017
> # hostname : triton
> # os release : 4.10.0-23-generic
> # perf version : 4.12.rc5.g9688eb
> # arch : x86_64
> # nrcpus online : 12
> # nrcpus avail : 12
> # cpudesc : Intel(R) Core(TM) i7-4960X CPU @ 3.60GHz
> # cpuid : GenuineIntel,6,62,4
> # total memory : 65917012 kB
> # cmdline : /home/mingo/bin/perf record /home/mingo/hackbench 10 

> let me know if you need more info.
> 
> Btw., note that there's also this warning:
> 
>   unwind: target platform=x86 is not supported
> 
> (but that's unrelated to this commit.)

Ok, what distro? Do you have libunwind-devel installed? I couldn't
reproduce this one here with/without it installed, to test I build it
with:

 make ARCH=x86_64 O=/tmp/build/perf -C tools/perf install-bin

and without that ARCH= setting, then I record with:

  perf record --call-graph dwarf -a sleep 2

and try what you said emitted that warning:

  perf report --stdio

- Arnaldo