rtems_semaphore_obtain question

[Miller, Scott A.]

We have a question about how the RTEMS binary semaphore behaves when attempting to take the semaphore twice within the same task context.


1. To create the semaphore, we run:


 rtems_semaphore_create(
        rtems_build_name('M','U','T','\0') + _al_bsem_mutex_cnt,
        1, /* FULL - since we are using this for mutual-exclusion */
        RTEMS_BINARY_SEMAPHORE |
        RTEMS_PRIORITY |
        RTEMS_LOCAL |
        RTEMS_INHERIT_PRIORITY,
        0,
        sem_p);


2. We then attempt to take it once, and it succeeds. We use:


    rtems_semaphore_obtain(
            *sem_p,
            RTEMS_WAIT,
            _Timespec_To_ticks(to));


3. We then take it again (from the same task context), and it succeeds. Again, we use:


    rtems_semaphore_obtain(
            *sem_p,
            RTEMS_WAIT,
            _Timespec_To_ticks(to));



We did not expect that (3) would succeed. If we attempt step (3), except from another task context, it fails (as expected).


Is it expected that (3) should succeed, given it is running in the same task context? The documentation does not appear to say, but perhaps we are missing something?
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