computer architecture - What' s the advantage of LL/SC comparing with CAS(compare and swap) -

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what' s advantage of ll/sc comparing cas(compare , swap) in computer architecture? think ll/sc can case livelock in many-core system, , case aba problem, cas not. can not find out advantage of ll/sc comparing cas. can tell me?

since nobody has answered, ll/sc not suffer aba problem since conditional store fail if address referenced ll modified. furthermore, can't livelock since 1 or more ll/sc pairs failing implies succeeded. cas potentially more expensive, since may require invalidate queue flushed.


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