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Date: Thu, 2 Sep 2004 14:02:47 -0700 (PDT)
From: Christoph Lameter <clameter@sgi.com>
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To: "David S. Miller" <davem@davemloft.net>
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Subject: Re: page fault scalability patch final : i386 tested, x86_64 support
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On Thu, 2 Sep 2004, David S. Miller wrote:

> On Thu, 2 Sep 2004 09:24:47 -0700 (PDT)
> Christoph Lameter <clameter@sgi.com> wrote:
>
> > Why was it done that way? Would it not be better to add the new
> > functionality by giving the function another name?
> >
> > Like f.e. set_pte_mm()
> >
> > then one could add the following in asm-generic/pgtable.h
> >
> > #ifndef __HAVE_ARCH_SET_PTE_MM
> > #define set_pte_mm(mm, address, ptep, pte) set_pte(ptep, pte)
> > #endif
> >
> > which would avoid having to update the other platforms and woud allow a
> > gradual transition.
>
> In order for it to be useful, every set_pte() call has to get the
> new args.  If there are exceptions, then it doesn't work out cleanly.

Yes. The mechanism that I proposed allows one to provide the info at each
call of set_pte_mm(). set_pte() would only be used for the arch specific
stuff and would become a legacy thing.

> I did all of the generic code, it's just each platform's code that
> needs updating.
>
> And BTW it's not just set_pte(), it's also pte_clear() and some of
> the other routines that need the added mm and address args.

Would not the generic code if done the way I suggested make the updating
of each platforms code unnecessary?

I have the similar issues with the page scalability patch. Should I not do
the legacy thing for platforms that do not have atomic pte operations?
'