hi,

> After digging into amd64 pmap details I came to the conclusion
> that it isn't helpful to merge them into one.
> They are so different. We have a different page table architecture,
> and we have a completely different address space layout.

they're similar enough, IMO.

> There might be common algorithms, but this the same as with
> any other architecture using in-memory page-tables.

yes, all of them might share some code.  what's wrong?

> Hiding the differences in macros or turning the code into
> an #ifdef mess would hinder further maintenance.
> (If you want a bad example, look at the mc68020/040 stuff.)

i don't know much about m68k.
but at a glance, it doesn't seem so bad to me.

i can't believe that duplicating code helps maintenance.
do you know the fact that there's a bug in amd64 pmap,
which is already fixed in i386?  (yes, it's my fault :-)

YAMAMOTO Takashi