rtems_event_receive and timeslicing

[Joel Sherrill]

Brett Swimley wrote:
> 
> I have a situation where I have two tasks running at the same priority (=
> 128). Both tasks were created with RTEMS_PREEMPT and
> RTEMS_TIMESLICE.
> 
> One task is blocked, waiting on an event that is sent by an ISR.  The other
> task is in an infinite loop as follows:
> 
> for ( ;; )
> {
>         ;
> }
> 
> The task that is blocked on the rtems_event_receive() never appears to
> receive the event.  However, if I place an
> 
>  rtems_task_suspend( RTEMS_SELF );
> 
> call prior to the infinite loop in the 2nd task - the first task does
> receive the event.
> 
> I won't have this task construct in the near future as I implement more
> functionality, but I would like to understand if the blocked task should run
> under this situation with timeslicing enabled.  If I am missing some
> configuration options as well, I would like to know.
> 
> I have
> #define CONFIGURE_TICKS_PER_TIMESLICE   50
> in my Initialization function file.
> 
> I'm currently using the rtems-ss-20010816 snapshot.

My guess is that you don't have a clock driver.  Or that you do
and the time quantum is larger than you think based upon
CONFIGURE_MICROSECONDS_PER_TICK and (CONFIGURE_TICKS_PER_TIMESLICE == 50).

A 10 millisecond tick (the default I think) and 50 ticks per
timeslice is 1/2 second per timeslice.  



> Thanks for any insight.
> 
> Regards,
> 
> Brett Swimley

-- 
Joel Sherrill, Ph.D.             Director of Research & Development
joel at OARcorp.com                 On-Line Applications Research
Ask me about RTEMS: a free RTOS  Huntsville AL 35805
Support Available                (256) 722-9985