Re: problem with gprof profiling when using cross compiler

[Mark Ahlenius <m_ahlenius at comcast dot net>]

Martin,

thanks for your response, but I am still not out of the water yet on 
this issue.  I recompiled the kernel with this CONFIG_PROFILING enabled 
(something like Experimental mode was the only choice).  And that solved 
one problem, so now we actually get the seconds (timing info).  But the 
times do not add up even closely to the wall clock time - like 3 minutes 
different for a 3.5minute run.  So I think there are other issues.

Someone told me, and I am not certain that I understand that once I 
create the kernel with this parameter enabled, and install it, that I 
have to rebuild my tool chain with it because there may be libs which 
are modified and that would effect the application which I just built.  
I'm not sure that I follow that - but does that sound correct?    How 
would building a kernel using a cross compiler for a target platform, 
need to effect the tool chain on the build machine?  Just guess I don't 
understand.

With an app with multi-threading going on, is there anything else which 
might need to be modified for profiling that you are aware of?  We do 
have a shared lib called gprof-helper.so installed on the target and loaded.

thanks a bunch,

'mark


\Martin Guy wrote:
> On 6/10/08, m_ahlenius@comcast.net <m_ahlenius@comcast.net> wrote:
>   
> >  I am not sure if this is the right place to ask this question.
> >     
>
> Probably not, but hey!
>
>   
> >  When I run gprof on either the Gumstix platform (with the exe file too) I get proper function counts, but all the timing values are 0.
> >     
>
> The kernel on your target board has been compiled without
> CONFIG_PROFILING configured in, so you need to make a new kernel for
> the target board.
>
>      M
>
>