[Syllable-kernel] Scheduler cleanup

[Daniel G. <da...@fp...>]

Hi, all.

Here's the first in a series of cleanup patches for the scheduler.  This
is all (hopefully) preperatory to porting Con Kolivas' staircase
scheduler from the linux -ck kernel.  This is the scheduler I use on all
my linux boxes, and it's absolutely great for desktops.

At anyrate, I went about these first two patches backwards.  The first
patch introduces a new, typesafe list primative, and uses it for the
scheduler's thread queues.  This should give a slight increase in speed,
but it's mostly so I can play around with the queues with a known
correct set of list primatives.  These are the same list primatives I
used in the tmpfs driver.  The second one is documentation and some
cleanup.  I know, they should have been the other way around, but...

Attached is the patch and the list header, which is assumed to be in
inc/list.h

I've tested this fairly thouroughly, and it works.  The second patch
will follow after I've finished testing it.   After that, my third patch
makes all WaitQueue_s objects use the list primatives as well.  After
that, I'll start making actual changes to the scheduler.

Daniel