Prefetch protocol for transactional memory

A computer program product to control processing of a prefetch request, the computer program product comprising a computer readable storage medium having program instructions embodied therewith, wherein the computer readable storage medium is not a transitory signal per se, the program instructions executable by a device to cause the device to perform a method comprising:

• generating, by a first processors in a multiprocessor system, a prefetch request and a tag that dictates processing the prefect request;
• sending, by one or more processors in the multiprocessor system, the prefetch request and the tag to a second processor in the multiprocessor system;
• generating, by one or more processors in the multiprocessor system, a conflict indication based on whether a concurrent processing of the prefetch request and an atomic transaction by the second processor would generate a conflict with a memory access that is associated with the atomic transaction;
• and
• based on an analysis of the conflict indication and the tag, processing, by the second processor in the multiprocessor system (i) either the prefetch request or the atomic transaction, or (ii) both the prefetch request and the atomic transaction.

A computer system to control processing of a prefetch request, the computer system comprising:

• one or more computer processors;
• at least one computer readable storage medium that is not a transitory signal per se;
• and
• program instructions stored on the at least one computer readable storage medium, the program instructions being executable by at least one computer processor of the one or more computer processors to cause the at least one computer processor to perform a method comprising:
• generating, by a first processors in a multiprocessor system, a prefetch request and a tag that dictates processing the prefect request;
• sending, by one or more processors in the multiprocessor system, the prefetch request and the tag to a second processor in the multiprocessor system;
• generating, by one or more processors in the multiprocessor system, a conflict indication based on whether a concurrent processing of the prefetch request and an atomic transaction by the second processor would generate a conflict with a memory access that is associated with the atomic transaction;
• and
• based on an analysis of the conflict indication and the tag, processing, by the second processor in the multiprocessor system (i) either the prefetch request or the atomic transaction, or (ii) both the prefetch request and the atomic transaction.