Re: [Announce] [patch] Modular Scheduler Core and Completely Fair Scheduler [CFS]

Ingo Molnar
2007-04-15T13:04:38Z

* Esben Nielsen <nielsen.esben@googlemail.com> wrote:

> I took a brief look at it. Have you tested priority inheritance?

yeah, you are right, it's broken at the moment, i'll fix it. But the
good news is that i think PI could become cleaner via scheduling
classes.

> As far as I can see rt_mutex_setprio doesn't have much effect on
> SCHED_FAIR/SCHED_BATCH. I am looking for a place where such a task
> change scheduler class when boosted in rt_mutex_setprio().

i think via scheduling classes we dont have to do the p->policy and
p->prio based gymnastics anymore, we can just have a clean look at
p->sched_class and stack the original scheduling class into
p->real_sched_class. It would probably also make sense to 'privatize'
p->prio into the scheduling class. That way PI would be a pure property
of sched_rt, and the PI scheduler would be driven purely by
p->rt_priority, not by p->prio. That way all the normal_prio() kind of
complications and interactions with SCHED_OTHER/SCHED_FAIR would be
eliminated as well. What do you think?

Ingo