Re: TLB tiredown by ASID bump

[der Mouse <mouse%Rodents-Montreal.ORG@localhost>]

> No.  The existance of ASIDs along with the hardware implementation is
> fundamentally a proprty of the MMU design.  Exposing this information
> outside of the MD code base (pmap(9)) breaks encapsulation.

In detail, yes.  In general, no.

I haven't looked at the ASID issue in detail.  But it sounds to me as
though it needs at least a few things elsewhere, though they can (and
probably should) be kept as general as feasible.  For example, every
process (or maybe lwp) needs to have an ASID hanging off it - but it
doesn't have to be done that way; I'd say it should be done by giving
each process (lwp) a pointer, or maybe a small block of data, which is
totally private to the pmap in use.  If pmap wants a call at process
exit, or syscall exit, or whatever, fine - but do it as a
general-purpose hook which the pmap in use can use to do whatever it
wants, not just ASID fiddling.

/~\ The ASCII                             Mouse
\ / Ribbon Campaign
 X  Against HTML                mouse%rodents-montreal.org@localhost
/ \ Email!           7D C8 61 52 5D E7 2D 39  4E F1 31 3E E8 B3 27 4B