Use compareAndExchange() in obvious places #179
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We have a few spots where we missed the opportunity to be more concise. Fix that up. Signed-off-by: Robert Varga <[email protected]>
compareAndExchange() is better than compareAndSwap() in that it provides the witness value. Switching casRoot() to this paradigm allows us to speed up speed up retries in rdcssComplete(). Signed-off-by: Robert Varga <[email protected]>
There are only two callers, who have the current value readily available. Use that value instead of reading it again. Signed-off-by: Robert Varga <[email protected]>
We are entering with a RDCSS_Descriptor, so let's not lose that information. The refactored loop is also denser, as we now share the code path taken for abort case and when the expected main changes. Signed-off-by: Robert Varga <[email protected]>
compareAndExchange() gives is the witness value, which we can use to elide a volatile read of main node. Signed-off-by: Robert Varga <[email protected]>
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Fixes #178.