Multi-processor system and method for synchronizing among processors with cache memory having reset state, invalid state, and valid state

摘要

In a multi-processor system including a plurality of processing units each having a cache memory, the processing units each include a synchronization counter for indicating a present synchronization state of the respective processing unit, and a cache state table for holding information regarding the respective entries of the cache memory. The cache state table includes a cache state and a cache synchronization count. The cache state holds the respective cache state used in a cache protocol. The cache synchronization count holds a value of the synchronization counter when an entry is loaded. A cache protocol in the multi-processor system is simplified to realize a high-speed processing.