The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 19, 2002
Filed:
Sep. 28, 1998
Brian R. Konigsburg, Austin, TX (US);
Alexander Edward Okpisz, Austin, TX (US);
Thomas Albert Petersen, Austin, TX (US);
Bruce Joseph Ronchetti, Austin, TX (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method and system of facilitating storage accesses within a multiprocessor system subsequent to a synchronization instruction by a local processor consists of determining if data for the storage accesses is cacheable and if there is a “hit” in a cache. If both conditions are met, the storage accesses return the data to the local processor. The storage accesses have an entry on an interrupt table which is used to discard the returned data if a snoop kills the line before the synchronization instruction completes. After the cache returns data, a return data bit is set in the interrupt table. A snoop killing the line sets a snooped bit in the interrupt table. Upon completion of the synchronization instruction, any entries in the interrupt table subsequent to the synchronization instruction that have the return data bit and snooped bit set are flushed. The flush occurs because the data returned to the local processor due to a “cacheable hit” subsequent to the synchronization instruction was out of order with the snoop and the processor must flush the data and go back out to the system bus for the new data.