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    SubjectRe: spin_unlock optimization(i386)
    Richard B. Johnson wrote:
    > The purpose of the lock prefix is not to make the current CPU operation
    > atomic. It's to make all other CPUs halt until the operation is complete.
    > This gurantees that only one CPU modifies the variable at the same
    > time. You are not going to do that with a move.

    AFAIK the reason the lock prefix is not permitted with move instructions
    is that there's no need. Lock makes read-modify-write instructions
    atomic. Aligned writes are atomic already.

    -- Jamie

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      Last update: 2005-03-22 13:55    [W:0.019 / U:38.568 seconds]
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