Re: [Qemu-devel] MMIO address changes

["Edgar E. Iglesias" <edgar.iglesias@axis.com>]

On Wed, Dec 03, 2008 at 02:03:53PM +0000, Paul Brook wrote:
> > > I've tried to be fairly thorough with the changes, and tested what I can.
> > > However it's possible I missed or broke something, so please test your
> > > favourite targets.
> >
> > FWIW the etrax-fs machine works OK although I am seeing a noticeable
> > slow-down after the patch.
> 
> Strange. I wouldn't expect significant slowdown.
> AFAIK the hot-path code should be pretty much unchanged (if anything faster 
> because the IO handlers don't need to adjust the address). Even the TLB fill 
> handler overhead (tlb_set_page_exec) should be negligible.

Hello Paul,

I went through your patch and AFAICT it looks fine. The only thing I saw
that may cause slowdowns was the size increase of PageDesc and subpage.

In case anybody want's to reproduce this, just start the etrax image I've
posted before, login trough telnet and do a ls -alR /, you'll see a very
noticeable difference.

Best regards
Edgar