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    SubjectRe: test13-pre5
    On Thu, Dec 28, 2000 at 02:54:52PM -0800, David S. Miller wrote:
    > Date: Thu, 28 Dec 2000 23:58:36 +0100
    > From: Andi Kleen <ak@suse.de>
    >
    > Why exactly a power of two ? To get rid of ->index ?
    >
    > To make things like "page - mem_map" et al. use shifts instead of
    > expensive multiplies...

    I thought that is what ->index is for ?

    Also gcc seems to be already quite clever at dividing through small
    integers, e.g. using mul and shift and sub, so it may not be even worth to reach
    for a real power-of-two.

    I suspect doing the arithmetics is at least faster than eating the
    cache misses because of ->index.

    -Andikkk


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