Re: [PAE support] Initial patch review

[Mindaugas Rasiukevicius <rmind%netbsd.org@localhost>]

Hello,

Jean-Yves Migeon <jeanyves.migeon%free.fr@localhost> wrote:
> 
> It diverges quite a bit from the original patch from Jeremy. Reason is 
> to avoid too many #ifdef's between Xen and non-Xen pmap <...>

Getting rid of #ifdefs, especially in pmap, is a right direction we
should continue moving in time.

> XXX misses support for ephemeral mapping. I am not sure on how to 
> implement it correctly, so pmap_load() uses tlbflush(). Same goes for 
> port-xen. I can revisit it later, after merging this patch + xen-suspend.

Which part of support?  It is same entering/removal of unmanaged mappings,
except without TLB flush (and IPIs).  These are something to track with
generation numbers, normally in such way:

        u_int gen = uvm_emap_gen_return();
        tlbflush();
        uvm_emap_update(gen);

> Any comments on the modifications there? I would prefer to have all 
> important changes "approved" before starting regression testing.

Do you have any data whether/how these changes affect performance?

I see some clean-ups and style changes in the patch - help (as well as
reviews and testing) on syncing of uvmplock branch would be useful, since
some parts of pmap are changed/split there.

Thanks for working on this!

P.S. Could you please generate patches with diff -p option?

-- 
Mindaugas