Re: [Xenomai-help] Debug/trace tools for xenomai applications.

[Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>]

Andreas Glatz wrote:
>> Now my question is: how do I investigate an issue like this? In other words,
>> which are the best tools since this code involves both user and kernel space
>> debugging.
>> Are there some trace tools available that are able to generate a kind of
>> sequence / trace of what is happing over time.
>>
>> I also have other issues that are not consistently reproducible. For this
>> kind of problems trace tools would also be useful.
>>
> 
> I have debugged such issues with LTTng ( http://lttng.org/ ). There
> are trace points in the Xenomai nucleus ( grep -rw xn_nucleus
> /path/to/xenomai/* ) and skins (at least the native skin). You could
> for example set up 'one-shot' tracing where events are continuously
> added to the Lttng event ring buffer until a condition is satisfied
> (i.e. your error condition) and analyse it either with Lttv or by
> looking at the textual output.
> 
> It takes some time to set things up. You need (1) to add the LTTng
> patches to your kernel and recompile the whole thing. In general,
> there are just LTTng patches for vanilla kernels available. So you
> have to expect some manual work there. (2) You have to compile the
> user-space daemon for your target: You need it to control the tracing.
> (3) Lttv for your host (if you like a little bit of comfort when
> analysing your traces).

Other means of debugging are gdb in user-space, and the I-pipe tracer in
kernel-space:
http://www.xenomai.org/index.php/I-pipe:Tracer

-- 
                                                                Gilles.