A system includes a plurality of processing clusters and a snoop controller. A
first processing cluster in the plurality of processing clusters includes a first
tier cache memory coupled to a second tier cache memory. The system employs a store-create
operation to obtain sole ownership of a full cache line memory location for the
first processing cluster, without retrieving the memory location from other processing
clusters. The system issues the store-create operation for the memory location
to the first tier cache. The first tier cache forwards a memory request including
the store-create operation command to the second tier cache. The second tier cache
determines whether the second tier cache has sole ownership of the memory location.
If the second tier cache does not have sole ownership of the memory location, ownership
of the memory location is relinquished by the other processing clusters with any
ownership of the memory location.
