A data processor (300) is adapted for use in a non uniform memory access (NUMA) data processing system (10) having a local memory (320) and a remote memory. The data processor (300) includes a central processing unit (302) and a communication link controller (310). The central processing unit (302) executes a plurality of instructions including an atomic instruction on a lock variable, and generates an access request that includes a lock acquire attribute in response to executing the atomic instruction on the lock variable. The communication link controller (310) is coupled to the central processing unit (302) and has an output adapted to be coupled to the remote memory, and selectively provides the access request with the lock acquire attribute to the remote memory if an address of the access request corresponds to the remote memory.