Re: [PATCH] perf report: auto-detect branch stack sampling mode

[Arun Sharma <asharma@fb.com>]

Like you probably figured from my other mail, we deal with deeply nested 
callchains with unwieldy function names a lot -- thanks to C++ and 
template programming. --tui's collapsing/expanding functionality is 
quite useful to navigate that mess. I'm just taking this opportunity to 
get some attention focused on improving it :)

On 3/5/12 2:26 PM, Arnaldo Carvalho de Melo wrote:

>> Here's an example:
>>
>> # perf record -ag -- sleep 3
>> # perf report -G -s pid --tui # SIGSEGV
>
> Ok, now this is a good report, I managed to reproduce and will work on a
> fix, thanks,

Something like this seems to do it for me.

         offset = addr - sym->start;
+       len = sym->end - sym->start;
+       if (offset >= len)
+               return 0;
+

The other problem area seems to be callchains when using -p regexp -x 
options. I'll try to summarize problems there in a separate thread.

  -Arun