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    SubjectRe: [PATCH 6/24] make atomic_read() behave consistently on frv
    Chris Snook wrote:
    > From: Chris Snook <csnook@redhat.com>
    >
    > Make atomic_read() volatile on frv. This ensures that busy-waiting
    > for an interrupt handler to change an atomic_t won't get compiled to an
    > infinite loop, consistent with SMP architectures.

    To head off the criticism, I admit this is an oversimplification, and true
    busy-waiters should be using cpu_relax(), which contains a barrier. As
    discussed in recent threads, there are other cases which can be optimized by
    removing the need for a barrier, and having behavior consistent with
    architectures where the benefit is more profound is also valuable.

    -- Chris
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