Henri Roosen wrote:
> We have the same requirement for which we also have no solution. One
> of our threads has a configurable priority of which at the lowest
> priority the thread should behave like an idle task that is only
> scheduled when all xenomai threads are idle and also the Linux domain
> is idle. The thread might use rtdm-drivers and xenomai mutexes and
> therefore has to be moved to the Xenomai domain. But then it always
> has higher priority than any threads scheduled in linux.

That's not true, Xenomai threads can run in non-RT scheduling classes as
well. They may just gain RT priority while holding some lock that is
requested by a RT thread as well.

> 
> Actually, when seen from the first domain, this requirement would be
> solved when we could set a first domain priority for the second
> domain... Gilles, is that what is meant by the SCHED_IDLE policy for
> Linux?

"nice +20", thus a very small CPU share if other task are runnable.

Note that "true" SCHED_IDLE, ie. no CPU share if some other task is
runnable, could only work if we forbid access to Linux syscalls for such
tasks - not feasible.

Jan

Attachment: signature.asc
Description: OpenPGP digital signature

_______________________________________________
Xenomai-help mailing list
[email protected]
https://mail.gna.org/listinfo/xenomai-help

Reply via email to