debugging multi threaded applicatiosn on arm - status?

debugging multi threaded applicatiosn on arm - status?

[Sam Ravnborg]

Is it possible to bebug multi-threaded applications using gdb on ARM these days?

We have had trobules getting this to work - but I do not have the details at hand atm.
I am just curious if this is supposed to work or not.

We have an arm target running: 2.6.32.8 #1 PREEMPT
CPU: ARM926EJ-S rev 5 (v5l) (Atmel AT91SAM9263)

The kernel is only lightly modifed - mostly with a few
propriatary drivers and a few driver hacks (not suitable for mainline).

It is a long story why we use such an old version.

Our applications uses threads and we use glibc 2.10.1 with NPTL enabled.
So far we have survived using the powerfull printf debugging :-)

	Sam

Re: debugging multi threaded applicatiosn on arm - status?

[Chris Simmonds]

On 17/06/11 10:39, Sam Ravnborg wrote:
> Is it possible to bebug multi-threaded applications using gdb on ARM these days?
>
> We have had trobules getting this to work - but I do not have the details at hand atm.
> I am just curious if this is supposed to work or not.
>
> We have an arm target running: 2.6.32.8 #1 PREEMPT
> CPU: ARM926EJ-S rev 5 (v5l) (Atmel AT91SAM9263)
>
> The kernel is only lightly modifed - mostly with a few
> propriatary drivers and a few driver hacks (not suitable for mainline).
>
> It is a long story why we use such an old version.
>
> Our applications uses threads and we use glibc 2.10.1 with NPTL enabled.
> So far we have survived using the powerfull printf debugging :-)
>
> 	Sam

It works for me, using various ARM 926 and Cortex A8 chips and kernel 
versions from 2.6.27 to the present day. Which version of gbd do you 
have? gdb version 7.x works much better than 6.x in my experience.

Chris Simmonds

Re: debugging multi threaded applicatiosn on arm - status?

[Sam Ravnborg]

>> Is it possible to bebug multi-threaded applications using gdb on ARM these days?
>>
>
> It works for me, using various ARM 926 and Cortex A8 chips and kernel  
> versions from 2.6.27 to the present day. Which version of gbd do you  
> have? gdb version 7.x works much better than 6.x in my experience.

We are using 6.8 - which may be the culprint.
Does it work with NPTL too?

	Sam

Re: debugging multi threaded applicatiosn on arm - status?

[Peter Waechtler]

Sam Ravnborg <sam <at> ravnborg.org> writes:
> 
> >> Is it possible to bebug multi-threaded applications using gdb on ARM these 
days?
> >>
> >
> > It works for me, using various ARM 926 and Cortex A8 chips and kernel  
> > versions from 2.6.27 to the present day. Which version of gbd do you  
> > have? gdb version 7.x works much better than 6.x in my experience.
> 
> We are using 6.8 - which may be the culprint.
> Does it work with NPTL too?
> 

Sam,

why don't you describe what's not working?

I guess you have a stripped libpthread and gdb isn't able to fetch
the thread infos via libthread_db.so.

On ARM you must not strip libpthread too much - see

http://sourceware.org/gdb/wiki/FAQ   question 6


  Peter