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@ -199,9 +199,10 @@ reordered to occur before it.
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When thread A releases a location in memory and then thread B subsequently
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acquires *the same* location in memory, causality is established. Every write
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that happened before A's release will be observed by B after its acquisition.
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However no causality is established with any other threads. Similarly, no
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causality is established if A and B access *different* locations in memory.
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(including non-atomic and relaxed atomic writes) that happened before A's
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release will be observed by B after its acquisition. However no causality is
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established with any other threads. Similarly, no causality is established
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if A and B access *different* locations in memory.
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Basic use of release-acquire is therefore simple: you acquire a location of
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memory to begin the critical section, and then release that location to end it.
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