Hi folks...

I've comitted new callout code to the NetBSD kernel.  The new API,
described in callout(9) completely replaces the old timeout()/untimeout()
API.

The new subsystem has two major improvements:

	- Clients provide storage for the callout data structures, thus
	  eliminating problems due to resource shortages (e.g. timeout
	  table full panics).

	- Insertion and removal of a callout is constant time, which
	  helps a lot since the callout facility used used a great
	  deal in the kernel.

I've been running this code for quite some time on some x86 and Alpha
systems and have noticed no problems.  I've verified that it builds on
arm32 and several m68k platforms, and I think SPARC (this was all before
I left NASA earlier this month).

The changes to convert code to the new API were basically mechanical,
and I sure hope I got it all right.  If not, it's likely that the code
will just fail to compile.  If you encounter any problem, please send
a bug report with send-pr(1) *immediately*, and I will address it ASAP.

Enjoy!

-- 
        -- Jason R. Thorpe <thorpej@zembu.com>