Re: [Xenomai] gdb / threads on beaglebone black

[Philippe Gerum <rpm@xenomai.org>]

On 05/28/2014 10:31 PM, Michael Haberler wrote:
>
> Am 28.05.2014 um 19:54 schrieb Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>:
>
>> On 05/28/2014 04:45 PM, Michael Haberler wrote:
>>>
>>> Am 28.05.2014 um 16:24 schrieb Philippe Gerum <rpm@xenomai.org>:
>>>
>>>> On 05/28/2014 04:08 PM, Drew wrote:
>>>>> Yes, my guess was correct.
>>>>> The do - while loop in trampoline is exiting with error -38 (-ENOSYS?)
>>>>> If I change line 110 of skins/native/task.c:
>>>>>
>>>>> - while(err == -EINTR)
>>>>> + while(err == -EINTR || err == -ENOSYS)
>>>>>
>>>>> then I'm able to single-step in gdb. :-)
>>>>>
>>>>> Is my change a hack, or is it the correct thing to do?
>>>
>>> I reproduced the behavior on an slightlier earlier kernel version than Drew used:
>>>
>>> config: http://static.mah.priv.at/public/config.txt
>>> dmesg: http://static.mah.priv.at/public/dmesg.txt
>>>
>>> $ cat /proc/ipipe/version
>>> 3
>>> $ cat /proc/xenomai/version
>>> 2.6.3
>>>
>>>>
>>>> No Xenomai call should ever return ENOSYS. Something is definitely wrong with the current setup.
>>>>
>>>>> It looks like rt_task_trampoline is only expecting EINTR to occur. Is
>>>>> some other bug causing ENOSYS?
>>>>
>>>> This means that the 'barrier' syscall did not get to Xenomai core, but was rejected as undefined.
>>>>
>>>> Could any of the hints mentioned here apply in your case?
>>>> http://www.xenomai.org/documentation/xenomai-2.6/html/TROUBLESHOOTING/#_any_xenomai_service_fails_with_code_38_enosys
>>>
>>> as above, I'm not seeing a violation of any of those conditions?
>>
>> Is there no message printed on the kernel console which would explain
>> why this syscall gets rejected?
>
> this is the complete session on the console:
>
> machinekit@beaglebone:~/xenomai-2.6/examples/native$ gdb trivial-periodic
> GNU gdb (GDB) 7.4.1-debian
> Copyright (C) 2012 Free Software Foundation, Inc.
> License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
> This is free software: you are free to change and redistribute it.
> There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
> and "show warranty" for details.
> This GDB was configured as "arm-linux-gnueabihf".
> For bug reporting instructions, please see:
> <http://www.gnu.org/software/gdb/bugs/>...
> Reading symbols from /home/machinekit/xenomai-2.6/examples/native/trivial-periodic...done.
> (gdb) r
> Starting program: /home/machinekit/xenomai-2.6/examples/native/trivial-periodic
> [Thread debugging using libthread_db enabled]
> Using host libthread_db library "/lib/arm-linux-gnueabihf/libthread_db.so.1".
> [New Thread 0xb6fc0470 (LWP 649)]
> [New Thread 0xb6e83470 (LWP 650)]
> [Thread 0xb6fc0470 (LWP 649) exited]
> [Thread 0xb6e83470 (LWP 650) exited]
> hello world
>
> ^C
> Program received signal SIGINT, Interrupt.
> 0xb6fa6fcc in pause () from /lib/arm-linux-gnueabihf/libpthread.so.0
> (gdb)
>
> dmesg is empty here

Even with CONFIG_IPIPE_DEBUG_INTERNAL turned on?

-- 
Philippe.