NetBSD master CVS tree commits

[source%NetBSD.ORG@localhost]

gwr
Mon Nov  3 08:08:25 PST 1997
Update of /cvsroot/src/sys/arch/sun3/sun3
In directory netbsd1:/var/slash-tmp/cvs-serv10337

Modified Files:
        pmap.c 
Log Message:
Implement a "kernel-only" context for processes that have not
touched any user-space address recently.  This is efficient
for things that stay in the kernel for a while, waking up
to handle some I/O then going back to sleep (i.e. nfsd).
If and when such a process returns to user-mode, it will
fault and be given a real context at that time.

This also makes context switch faster, because all we need
to do there for the MMU is slam the context register.