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    SubjectRe: [PATCH] tcp_cubic: use 32 bit math
    David Miller wrote:
    > From: Stephen Hemminger <shemminger@linux-foundation.org>
    > Date: Wed, 7 Mar 2007 17:07:31 -0800
    >
    >
    >> The basic calculation has to be done in 32 bits to avoid
    >> doing 64 bit divide by 3. The value x is only 22bits max
    >> so only need full 64 bits only for x^2.
    >>
    >> Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
    >>
    >
    > Applied, thanks Stephen.
    >
    > What about Willy Tarreau's supposedly even faster variant?
    > Or does this incorporate that set of improvements?
    >
    That's what this is:
    x = (2 * x + (uint32_t)div64_64(a, (uint64_t)x*(uint64_t)x)) / 3;

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