lkml.org 
[lkml]   [2015]   [Nov]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 2/3] perf tools: Add callchain order support for libunwind DWARF unwinder
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?

thanks,
jirka


\
 
 \ /
  Last update: 2015-11-18 09:21    [W:0.046 / U:8.020 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site