[ECOS] using threads causes exceptions

[Stefan Sommerfeld]

Hi,
>> >> >>
>> >> >> I'm using eCos on an XScale PXA270 and i have a problem using
>> >> >> threads.
>> >> >> My
>> >> >> program does only start a thread from main() and after this 
>> >> >> function
>> >> >> calls
>> >> >> from thread causes ABORT DATA exceptions (MMU info: Imprecise
>> >> >> External
>> >> >> Data
>> >> >> Abort). Even a printf causes this exception. The strange thing is,
>> >> >> the
>> >> >> eCos
>> >> >> thread tests are working, even the stress test. Do i have to do 
>> >> >> some
>> >> >> initialisation? Should i better use cyg_start() instead of main()?
>> >> >
>> >> > Using main() is just fine.  Most likely, you've not created the
>> >> > stack for the thread correctly.  Or perhaps it's something within
>> >> > your thread itself.
>> >> >
>> >> > Have you tried running the program using GDB?  Then you can catch
>> >> > the culprit and know where to start looking.
>> >>
>> >> So ... made it through gdb which gave me:
>> >> [New Thread 2]
>> >>
>> >> Program received signal SIGTRAP, Trace/breakpoint trap.
>> >> [Switching to Thread 2]
>> >> 0xa008c72c in main_stack ()
>> >>
>> >> This version is a bit smaller and does give me no exceptions like 
>> >> ABORT
>> >> DMA, but only the gdb output. Any suggestions?
>> >
>> > It's pretty obvious that you've not set your thread up properly
>> > since it's trying to execute from the stack!  Look carefully at
>> > how you created the thread - compare it against the examples and
>> > tests.
>>
>> >From gdb it looks like a corrupt stack, but i don't why.
>>
>> > If you still can't figure out what's wrong, you could send a
>> > *fragment* of your code, showing how you are creating the thread,
>> > etc.  Note: we don't want/need to see your whole program, just
>> > this portion.
>>
>> #define STACK_SIZE (CYGNUM_HAL_STACK_SIZE_TYPICAL*2)
>>
>> static cyg_thread thread_data;
>> static cyg_handle_t thread_handle;
>>
>> static void decoder_audio(cyg_addrword_t data)
>> {
>>  diag_printf("i'm here\n");
>>  // more complex C++ stuff here
>>  // and a endless loop calling some methods
>> }
>>
>>
>> int main(void)
>> {
>>  void *stack = malloc(STACK_SIZE);
>>
>>  cyg_thread_create(0,                // Priority - just a number
>>   test_thread,          // entry
>    ^^^^^^^^^^^
>
> What is this?  It should be the entry point to your thread - maybe
> 'decoder_audio'?

Yes, of course. I changed it to test_thread for the source snipp, but 
actual entry is decode_audio. I see the diag_printf from the thread.

Bye... 


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