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SubjectRe: [beta patch] SSE copy_page() / clear_page()
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> > +		__asm__ __volatile__(
> > + "mov %1, %0\n\t"
> > + : "=r" (i)
> > + : "r" (kaddr+offset)); /* load tlb entry */
> > + for(i=0;i<size;i+=64) {
> > + __asm__ __volatile__(
> > + "prefetchnta (%1, %0)\n\t"
> > + "prefetchnta 32(%1, %0)\n\t"
> > + : /* no output */
> > + : "r" (i), "r" (kaddr+offset));
> > + }
> > + }
> > left = __copy_to_user(desc->buf, kaddr + offset, size);
> > kunmap(page);
>
> This seems bogus -- you need to handle faults --
> i.e. __prefetchnta_to_user() ;-).

It wants wrapping nicely. A generic prefetch and prefetchw does help some other
cases (scheduler for one).

Does the prefetch instruction fault on PIII/PIV then - the K7 one appears not
to be a source of faults

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