Re: [PATCH V8 08/25] perf tools: Add Intel BTS support

[Adrian Hunter <adrian.hunter@intel.com>]

On 17/08/15 22:58, Arnaldo Carvalho de Melo wrote:
> Em Mon, Aug 17, 2015 at 10:09:26PM +0300, Adrian Hunter escreveu:
>> On 17/08/2015 8:58 p.m., Arnaldo Carvalho de Melo wrote:
>>> Em Mon, Aug 17, 2015 at 08:43:09PM +0300, Adrian Hunter escreveu:
>>>> On 17/08/2015 6:52 p.m., Arnaldo Carvalho de Melo wrote:
>>>>>      1.92%  usleep   [unknown]         [.] 0x00007fa0ff695086
>>>>>      1.60%  usleep   [unknown]         [.] 0xffffffff811c91d0
>>>>>      1.48%  usleep   [unknown]         [.] 0x00007fa0ffb3030d
>>>>>      1.24%  usleep   [unknown]         [.] 0x00007fa0ff6950c7
>>>
>>>> It is very weird that it doesn't know the dso.
>>>
>>>> I presume there is nothing unusual about the environment e.g. in a chroot or anything
>>>
>>>> What if you try a different event e.g. perf record --per-thread -e cycles sleep 1
>>>
>>> [root@zoo ~]# perf record --per-thread -e cycles sleep 1
>>> [ perf record: Woken up 1 times to write data ]
>>> [ perf record: Captured and wrote 0.014 MB perf.data (9 samples) ]
>>> [root@zoo ~]# perf report | grep -v ^# | head -5
>>>     42.57%  sleep    libc-2.20.so      [.] malloc_hook_ini
>>>     41.81%  sleep    [kernel.vmlinux]  [k] filemap_fault
>>>     14.35%  sleep    [kernel.vmlinux]  [k] flush_tlb_mm_range
>>>      1.18%  sleep    [kernel.vmlinux]  [k] strlcpy
>>>      0.09%  sleep    [kernel.vmlinux]  [k] native_write_msr_safe
>>> [root@zoo ~]#
>>>
>>> [root@zoo ~]# perf report --dsos libc-2.20.so | grep -v '^[#]'
>>>     42.57%  sleep    [.] malloc_hook_ini
>>>
>>> [root@zoo ~]#
>>>
>>> [root@zoo ~]# perf record --per-thread -e intel_bts// usleep 1
>>> [ perf record: Woken up 1 times to write data ]
>>> [ perf record: Captured and wrote 1.825 MB perf.data ]
>>> [root@zoo ~]# perf report | grep -v ^# | head -5
>>> Warning:
>>> 79074 instruction trace errors
>>>      2.80%  usleep   [unknown]         [.] 0x00007f48888aa061
>>> [root@zoo ~]#
>>
>> Running out of ideas.  Can you somehow share or send me the offending perf.data file?
> 
> http://vger.kernel.org/~acme/perf/perf.data.intel_bts-4.2.0-rc5+.xz

Says: You don't have permission to access
/~acme/perf/perf.data.intel_bts-4.2.0-rc5+.xz on this server.

> 
> It works if I use a tip/master kernel:
> 
> [root@perf4 ~]# uname -r
> 4.2.0-rc7+
> [root@perf4 ~]# uname -r
> 4.2.0-rc7+
> [root@perf4 ~]# perf record --per-thread -e intel_bts// usleep 1
> [ perf record: Woken up 1 times to write data ]
> [ perf record: Captured and wrote 1.785 MB perf.data ]
> [root@perf4 ~]# dmesg | grep Performance
> [    0.188477] Performance Events: PEBS fmt2+, 16-deep LBR, Broadwell
> events, full-width counters, Intel PMU driver.
> [root@perf4 ~]# perf report --stdio | grep -v ^# | head -10
> 
> 
> 
> 
>     10.81%  usleep   libc-2.17.so       [.] _dl_addr                            
>      6.56%  usleep   [kernel.kallsyms]  [.] unmap_single_vma                    
>      3.33%  usleep   ld-2.17.so         [.] strcmp                              
>      2.53%  usleep   [kernel.kallsyms]  [.] mem_cgroup_begin_page_stat          
>      2.49%  usleep   ld-2.17.so         [.] _dl_lookup_symbol_x                 
>      2.39%  usleep   ld-2.17.so         [.] _dl_relocate_object                 
> [root@perf4 ~]# 
> 
> Probably some fix for the kernel driver is missing?

Works for me though.