be locked before it can be marked as `active' on a processor.
- Require that pmaps other than the kernel pmap be locked when they
are passed to pmap_tlb_shootdown(). This, combined with the locking
protocol tweak, allow us to get a consistent view of `activeness' of
a pmap, which means we can optmize away a lot of TLB shootdown traffic
for user pmaps.
- Borrow an idea from the i386mp branch; use the normal SHOOTDOWN IPI
to deal with hitting the entire TLB, and garbage-collect the TBIA
and TBIAP IPIs.
ff62d4c0c5