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    SubjectRe: [PATCH] Document Linux's memory barriers
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    On Tue, 2006-03-07 at 12:57 +0100, Andi Kleen wrote:

    > > > True, I suppose. I should make it clear that these accessor functions imply
    > > > memory barriers, if indeed they do,
    > >
    > > They don't, but according to Documentation/DocBook/deviceiobook.tmpl
    > > they are performed by the compiler in the order specified.
    >
    > I don't think that's correct. Probably the documentation should
    > be fixed.

    That's why I hedged my words with "according to ..." :-)

    But on most arches those accesses do indeed seem to happen in-order. On
    i386 and x86_64, it's a natural consequence of program store ordering.
    On at least some other arches, there are explicit memory barriers in the
    implementation of the access macros to force this ordering to occur.

    <b

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