Task sync problems related with binary semaphore and cache memories
Arturo Perez Garcia
arturo.perez at upm.es
Wed Nov 28 10:52:48 UTC 2018
Yes, I'm checking the return status always. When I create the RTEMS
objects and when I acquire/release the semaphore. I removed those checks
from the code I put in the previous message.
El 2018-11-28 11:42, Sebastian Huber escribió:
> On 28/11/2018 11:30, Arturo Perez Garcia wrote:
>> Disabling the caches don't fixe the problem, I was wrong.
>> Maybe I'm initializing wrongly the RTEMS objects.
>> In the Init task I create the binary semaphore:
>> rtems_semaphore_create(a3_sem_name, 1,
>> RTEMS_BINARY_SEMAPHORE | RTEMS_FIFO | RTEMS_LOCAL, 0, &a3_sem_id);
>> Then I create 2 tasks with different priority:
>> t_matmul_name, 1, RTEMS_MINIMUM_STACK_SIZE * 2,
>> RTEMS_LOCAL, &t_matmul_id
>> t_inout_name, 2, RTEMS_MINIMUM_STACK_SIZE * 2,
>> RTEMS_LOCAL, &t_inout_id
>> The tasks must be synchronized through the semaphore, but they are
>> not. The semaphore is acquired by both tasks consecutively before it
>> has been released.
>> I suppose that it is due to an error in my BSP implementation, but I
>> don't know how to test it.
> Did you test that the returned status code is RTEMS_SUCCESSFUL in all
Arturo Perez Garcia - arturo.perez at upm.es
Center of Industrial Electronics
Universidad Politecnica de Madrid
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