Re: [patch 1] Xen core patch : ptep_establish_new

From: Paul Mackerras
Date: Thu Nov 18 2004 - 17:15:15 EST


Christoph Hellwig writes:

> On Wed, Nov 17, 2004 at 11:46:50PM +0000, Ian Pratt wrote:
> >
> > This patch adds 'ptep_establish_new', in keeping with the
> > existing 'ptep_establish', but for use where a mapping is being
> > established where there was previously none present. This
> > function is useful (rather than just using set_pte) because
> > having the virtual address available enables a very important
> > optimisation for arch-xen. We introduce
> > HAVE_ARCH_PTEP_ESTABLISH_NEW and define a generic implementation
> > in asm-generic/pgtable.h, following the pattern of the existing
> > ptep_establish.
>
> What would be the problem of always passing the virtual address to
> ptep_establish? We already have a rather twisted maze of pte manipulation
> macros.

Dave Miller had a patch that passes the mm and virtual address to
set_pte. That helps on sparc64 and ppc/ppc64, and it sounds like it
would help here too.

Paul.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/