Memory orderings for compare-and-set operations.
A compare-and-set operation can have different memory orderings depending on whether it succeeds or fails. This trait generalizes different ways of specifying memory orderings.
The two ways of specifying orderings for compare-and-set are:
- Just one
Orderingfor the success case. In case of failure, the strongest appropriate ordering is chosen.
- A pair of
Orderings. The first one is for the success case, while the second one is for the failure case.
The ordering of the operation when it succeeds.
The ordering of the operation when it fails.
The failure ordering can't be
AcqRel and must be equivalent or weaker than
the success ordering.