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    SubjectRe: [PATCH 0/24] make atomic_read() behave consistently across all architectures
    Christoph Lameter writes:

    > A volatile default would disable optimizations for atomic_read.
    > atomic_read without volatile would allow for full optimization by the
    > compiler. Seems that this is what one wants in many cases.

    Name one such case.

    An atomic_read should do a load from memory. If the programmer puts
    an atomic_read() in the code then the compiler should emit a load for
    it, not re-use a value returned by a previous atomic_read. I do not
    believe it would ever be useful for the compiler to collapse two
    atomic_read statements into a single load.

    Paul.
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