Real Time Runqueue

[Mike Kravetz]

As you may know, a few of us are experimenting with multi-runqueue
scheduler implementations.  One area of concern is where to place
realtime tasks.  It has been my assumption, that POSIX RT semantics
require a specific ordering of tasks such as SCHED_FIFO and SCHED_RR.
To accommodate this ordering, I further believe that the simplest
solution is to ensure that all realtime tasks reside on the same
runqueue.  In our MQ scheduler we have a separate runqueue for all
realtime tasks.  The problem is that maintaining a separate realtime
runqueue is a pain and results in some fairly complex/ugly code.

Since I'm not a realtime expert, I would like to ask if my assumption
about strict ordering of RT tasks is accurate.  Also, is anyone aware
of other ways to approach this problem?

Thanks,
-- 
Mike