Re: [patch] Prefetching file_read_actor()

From: Dave Jones (davej@suse.de)
Date: Mon Dec 31 2001 - 15:31:22 EST

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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.
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