Marc Kleine-Budde wrote:
> Hi Philippe!
>
> On Tue, Aug 03, 2004 at 10:40:47PM +0200, Marc Kleine-Budde wrote:
> > Can please tell me the differences between and constraints of:
> >
> > xnshadow_schedule() - issued a syscall, which is handled in the rthal
> > domain and calls there the scheduler, allowed from
> > linux domain (also from rthal, but makes no sense)
> > xnpod_schedule() - directly calls the scheuler, only permitted from
> > the rthal domain
> >
> > i think i've understand the usage of the 2 above, but i don't get when
> > to use this one....
> >
> > xnarch_escalate() - triggers an adeos irq, which is handeled in rthal
> > domain (?), sets resched bit and calls the scheuler
The irq handler is xnpod_schedule_handler, the reason why it sets the
resched bit is because this handler is also used to handle reschedule
IPIs, this is useless when triggering an escalation request.
The escalation request is used to cause the execution of real-time tasks
in the rtai domain when they are created from the Linux domain. If we
did not use this mechanism, the real-time task could run in the Linux
domain, and be interrupted by Linux IRQs, which is not what we want...
Regards.
--
Gilles Chanteperdrix.
