Re: [XenPPC] PATCH: Inline assembler for clear_page() and copy_page()

[Hollis Blanchard <hollisb@xxxxxxxxxx>]

On Mon, 2006-08-28 at 11:58 -0400, Jimi Xenidis wrote:
> On Aug 28, 2006, at 11:49 AM, Hollis Blanchard wrote:
> 
> > On Mon, 2006-08-28 at 11:31 -0400, Jimi Xenidis wrote:
> >> On Aug 28, 2006, at 10:50 AM, Hollis Blanchard wrote:
> >>
> >>>
> >>> Also, it looks like you've removed support for mambo_memcpy(). I  
> >>> don't
> >>> use Mambo *ahem* systemsim myself, but that seems worth keeping. I
> >>> guess
> >>> you could rename the function while you're in there. :)
> >>
> >> if we get these down to dcbz's then system performance is fine and am
> >> happy to drop.
> >
> > I think you're saying that if we have a clear_page() loop that uses
> > dcbz, systemsim performance is fine. Is that correct?
> yes

Is that just because it reduces the number of loops? Using 128 byte
increments instead of 8 would reduce the iterations from 512 to 32.

> >
> > Is that also the case for copy_page()?
> 
> No but it is not called to often, infact not at all AFAICT. I just  
> removed it and build fine :)
> Thats not to say that there aren't any opportunities to use it.

Right. As long as we're changing this code, let's include copy_page().

... which brings us back to the original patch a) removing the call to
mambo_memcpy(), and b) missing dcbtst.

-- 
Hollis Blanchard
IBM Linux Technology Center


_______________________________________________
Xen-ppc-devel mailing list
Xen-ppc-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-ppc-devel