Andrew Doran wrote:
>
> As an aside the amd64 pmap is lacking the lazy switching that the i386 pmap
> does, which eliminates reloads of %cr3 / TLB flushes when switching to
> kthreads, or when switching between threads within the same process. Also
> IIRC the xen pmap is an old, slightly modified version of the i386 pmap and
> should be merged back in with an #ifdef XEN.
>
> The amd64 pmap was written to work on i386 too. Can anyone comment on what
> the original issues were that prevented sharing it? Frank?
>   
yamt resolved any remaining issues and came up with a shared pmap. I 
agree that it should be shared, however, others disagreed, and the 
shared pmap was not committed.

I don't remember what the arguments were. I still think that a shared 
pmap should be committed.

- Frank