Re: [PATCH v6 6/6] perf util: use correct IP mapping to find srcline for hist entry

[Milian Wolff <milian.wolff@kdab.com>]

On Mittwoch, 18. Oktober 2017 20:53:50 CEST Milian Wolff wrote:
> When inline frame resolution is disabled, a bogus srcline is obtained
> for hist entries:
> 
> ~~~~~
> $ perf report -s sym,srcline --no-inline --stdio -g none
>     95.21%     0.00%  [.] __libc_start_main                                 
>                                                                 
> __libc_start_main+18446603358170398953 95.21%     0.00%  [.] _start        
>                                                                            
>                          _start+18446650082411225129 46.67%     0.00%  [.]
> main                                                                       
>                                         main+18446650082411225208 38.75%   
>  0.00%  [.] hypot                                                          
>                                                    
> hypot+18446603358164312084 23.75%     0.00%  [.] main                      
>                                                                            
>              main+18446650082411225151 20.83%    20.83%  [.]
> std::generate_canonical<double, 53ul,
> std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul>
> >  random.h:143 18.12%     0.00%  [.] main                                 
>                                                                            
>   main+18446650082411225165 13.12%    13.12%  [.]
> std::generate_canonical<double, 53ul,
> std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul>
> >  random.tcc:3330 4.17%     4.17%  [.] __hypot_finite                     
>                                                                            
>     __hypot_finite+163 4.17%     4.17%  [.] std::generate_canonical<double,
> 53ul, std::linear_congruential_engine<unsigned long, 16807ul, 0ul,
> 2147483647ul> >  random.tcc:3333 4.17%     0.00%  [.] __hypot_finite       
>                                                                            
>                   __hypot_finite+18446603358164312227 4.17%     0.00%  [.]
> std::generate_canonical<double, 53ul,
> std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul>
> >  std::generate_canonical<double, 53ul, std::line 2.92%     0.00%  [.]
> std::generate_canonical<double, 53ul,
> std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul>
> >  std::generate_canonical<double, 53ul, std::line 2.50%     2.50%  [.]
> __hypot_finite                                                             
>                                         __hypot_finite+11 2.50%     2.50% 
> [.] __hypot_finite                                                         
>                                             __hypot_finite+24 2.50%    
> 0.00%  [.] __hypot_finite                                                  
>                                                   
> __hypot_finite+18446603358164312075 2.50%     0.00%  [.] __hypot_finite    
>                                                                            
>                      __hypot_finite+18446603358164312088 ~~~~~
> 
> Note how we get very large offsets to main and cannot see any srcline
> from one of the complex or random headers, even though the instruction
> pointers actually lie in code inlined from there.
> 
> This patch fixes the mapping to use map__objdump_2mem instead of
> map__objdump_2mem in hist_entry__get_srcline. This fixes the srcline
> values for me when inline resolution is disabled:
> 
> ~~~~~
> $ perf report -s sym,srcline --no-inline --stdio -g none
>     95.21%     0.00%  [.] __libc_start_main                                 
>                                                                 
> __libc_start_main+233 95.21%     0.00%  [.] _start                         
>                                                                            
>         _start+41 46.88%     0.00%  [.] main                               
>                                                                            
>     complex:589 43.96%     0.00%  [.] main                                 
>                                                                            
>   random.h:185 38.75%     0.00%  [.] hypot                                 
>                                                                            
>  hypot+20 20.83%     0.00%  [.] std::generate_canonical<double, 53ul,
> std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul>
> >  random.h:143 13.12%     0.00%  [.] std::generate_canonical<double, 53ul,
> std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul>
> >  random.tcc:3330 4.17%     4.17%  [.] __hypot_finite                     
>                                                                            
>     __hypot_finite+140715545239715 4.17%     4.17%  [.]
> std::generate_canonical<double, 53ul,
> std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul>
> >  std::generate_canonical<double, 53ul, std::line 4.17%     0.00%  [.]
> __hypot_finite                                                             
>                                         __hypot_finite+163 4.17%     0.00% 
> [.] std::generate_canonical<double, 53ul,
> std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul>
> >  random.tcc:3333 2.92%     2.92%  [.] std::generate_canonical<double,
> 53ul, std::linear_congruential_engine<unsigned long, 16807ul, 0ul,
> 2147483647ul> >  std::generate_canonical<double, 53ul, std::line 2.50%    
> 2.50%  [.] __hypot_finite                                                  
>                                                   
> __hypot_finite+140715545239563 2.50%     2.50%  [.] __hypot_finite         
>                                                                            
>                 __hypot_finite+140715545239576 2.50%     2.50%  [.]
> std::generate_canonical<double, 53ul,
> std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul>
> >  std::generate_canonical<double, 53ul, std::line 2.50%     2.50%  [.]
> std::generate_canonical<double, 53ul,
> std::linear_congruential_engine<unsigned long, 16807ul, 0ul, 2147483647ul>
> >  std::generate_canonical<double, 53ul, std::line 2.50%     0.00%  [.]
> __hypot_finite                                                             
>                                         __hypot_finite+11 ~~~~~
> 
> Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
> Cc: Namhyung Kim <namhyung@kernel.org>
> Cc: Yao Jin <yao.jin@linux.intel.com>
> Cc: Jiri Olsa <jolsa@redhat.com>
> Signed-off-by: Milian Wolff <milian.wolff@kdab.com>
> 
> Note how most of the large offset values are now gone. Most notably,
> we get proper srcline resolution for the random.h and complex headers.
> ---
>  tools/perf/util/sort.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/tools/perf/util/sort.c b/tools/perf/util/sort.c
> index 006d10a0dc96..6f3d109078a3 100644
> --- a/tools/perf/util/sort.c
> +++ b/tools/perf/util/sort.c
> @@ -334,7 +334,7 @@ char *hist_entry__get_srcline(struct hist_entry *he)
>  	if (!map)
>  		return SRCLINE_UNKNOWN;
> 
> -	return get_srcline(map->dso, map__rip_2objdump(map, he->ip),
> +	return get_srcline(map->dso, map__objdump_2mem(map, he->ip),
>  			   he->ms.sym, true, true);
>  }

Sorry, this patch was declined by Nahmyung before, please discard it - I 
forgot to do that before resending v6.

Bye

-- 
Milian Wolff | milian.wolff@kdab.com | Senior Software Engineer
KDAB (Deutschland) GmbH&Co KG, a KDAB Group company
Tel: +49-30-521325470
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