Re: Problems with priorities in epicsThreadCreate (part of the EPICS OSI software layer)

[Andrew Johnson <anj@aps.anl.gov>]

Hi Goetz,

On 2012-02-20 Eric Norum wrote:
> How about calling the RTEMS rtems_task_set_priority routine from the
> beginning of your new thread?

I think I prefer Eric's suggestion to adding anything to the epicsThread API.

For each particular OS you will already need an OS-specific numeric priority, 
so you'll have to have OS-specific code in the source file anyway.  In that 
case you can just call the OS-specific API to change the new thread's 
priority.  For vxWorks and RTEMS that would mean adding something like this:

#if defined(vxWorks)
    taskPrioritySet(0, 66);
#elif defined(RTEMS)
    {
        rtems_task_priority old;
        rtems_task_set_priority(RTEMS_SELF, 66, &old);
    }
#endif

Now it's obvious that the this is OS-specific code, and the thread priority 
can be easily set to whatever is appropriate for the OS.

- Andrew
-- 
Optimization is the process of taking something that works and
replacing it with something that almost works, but costs less.
-- Roger Needham