Is there any real use in having a ctor/dtor for the pgd cache? Given
that all pgd allocation happens via pgd_alloc/pgd_free, why not just
fold the [cd]tor in?
I'm asking because Xen wants pgd[3] to be unshared in the PAE case, and
it looks to me like the easiest way to handle that is by making
pgd_alloc/free pv-ops and doing the appropriate thing in the Xen code.
Would need to sort out the vmalloc mapping replication as well, but I
think that's pretty straightforward.
J
