Re: Inquiry: Should we remove "isolcpus= kernel boot option? (may have realtime uses)

[Peter Zijlstra <a.p.zijlstra@chello.nl>]

On Wed, 2008-06-04 at 21:44 +0000, Michael Trimarchi wrote:
> [ sorry if this is going OT ]
>  
> Hi,
>  
> >  
> > Furthermore, cpusets allow for isolated but load-balanced RT domains. We
> > now have a reasonably strong RT balancer, and I'm looking at implementing
> > a full partitioned EDF scheduler somewhere in the future.
> >  
>  
> I'm working on a partitioned EDF scheduler right now, and I have to
> face several issues, starting from the interface to use to expose the
> EDF scheduler to userspace, and the integration with the existing
> sched_rt policy.

I would add a sched_class above sched_rt and let sched_rt run in all
unclaimed time by sched_edf.

Have you looked at deadline inheritance to replace PI? I think it can be
done reasonably simple by replacing the plist with a RB tree.

> By now I'm experimenting with an additional sched_class that implements
> a SCHED_EDF policy, extending the POSIX struct sched_param with the
> EDF parameters of the task, do you see any better way to do that? 
> Could that approach be reasonable?

Yes, that is the way I'm leaning.