Re: RT task scheduling

[Bill Huey (hui) <billh@gnuppy.monkey.org>]

On Fri, Apr 07, 2006 at 01:29:56PM +0200, Ingo Molnar wrote:
> * Bill Huey <billh@gnuppy.monkey.org> wrote:
> > First thing's first, SCHED_FIFO_GLOBAL for what you want in the main 
> > line is the same thing as SCHED_FIFO in -rt, right ?
> 
> yes.

Ok, good, we're getting some where. IMO, SCHED_FIFO_GLOBAL doesn't add
anything to existing Linux scheduling policies for it to be really
distinct than SCHED_FIFO. I'd much see that feature collapsed into a
into SCHED_FIFO intrinsically. In fact, that's the way it should be in
a solid RTOS. Creation of run categories that are so similar doesn't
really add to the "meaning" of the system, since SCHED_FIFO was kind
of hammered in the first place, just make SCHED_FIFO do that strict
priority stuff across all processors as a default property.

Whether this belongs in the main line or not is questionable. My guess
is probably not. But I definitely think it should go into -rt and it
would be much more warmly received by folks developing on that kernel
patch to know that SCHED_FIFO has this strict behavior. It's actually
needed in that patch IMO. Following ?

bill