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    SubjectRe: [PATCH 0/24] make atomic_read() behave consistently across all architectures
    On Fri, 24 Aug 2007, Denys Vlasenko wrote:

    > On Thursday 16 August 2007 00:22, Paul Mackerras wrote:
    > > Satyam Sharma writes:
    > > In the kernel we use atomic variables in precisely those situations
    > > where a variable is potentially accessed concurrently by multiple
    > > CPUs, and where each CPU needs to see updates done by other CPUs in a
    > > timely fashion. That is what they are for. Therefore the compiler
    > > must not cache values of atomic variables in registers; each
    > > atomic_read must result in a load and each atomic_set must result in a
    > > store. Anything else will just lead to subtle bugs.
    >
    > Amen.

    A "timely" fashion? One cannot rely on something like that when coding.
    The visibility of updates is insured by barriers and not by some fuzzy
    notion of "timeliness".
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