Messages in this thread | | | Date | Mon, 31 Dec 2001 20:31:22 +0000 | From | Dave Jones <> | Subject | Re: [patch] Prefetching file_read_actor() |
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On Mon, Dec 31, 2001 at 11:58:27AM +0100, Manfred Spraul wrote: > > What happens if a prefetch spills over the end of the page and > > faults?
> Doesn't hurt, prefetch instruction never cause page faults. > BUT: Prefetch doesn't preload the TLB. If the TLB entry for the kmap is > not in the TLB, all prefetch instructions are treated as nops.(on pIII).
Wasn't this the reason for the voodoo workaround we have in the mmx version of fast_copy_page() ?
Dave.
-- Dave Jones. http://www.codemonkey.org.uk SuSE Labs. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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