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    SubjectRe: RFC: remove __read_mostly
    On Thu, Dec 13, 2007 at 11:20:44PM +0100, Adrian Bunk wrote:
    > Is there anywhere in the kernel a case where __read_mostly brings a
    > measurable improvement or can it be removed?

    Yes, definitely[1]... the problem is, and this is also true of other
    annotations[2], that people go absolutely nuts adding these annotations
    without doing any profiling to see whether they actually improve things.

    I'd bet, in the __read_mostly case at least, that there's no
    improvement in almost all cases.

    cheers, Kyle

    1. It's hugely relevant on big-SMP machines.
    2. I mean __read_mostly, likely, unlikely, etc., not the useful sparse

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      Last update: 2007-12-14 00:57    [W:0.019 / U:16.228 seconds]
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