Patent ID: 7325102
Filing Date: 2008-01-29
Classification: G06F

Abstract:
1. A mechanism for filtering snoop requests to a cache memory, said mechanism comprising: a first storage including a first plurality of entries configured to store corresponding first snoop filter indications; a second storage including a second plurality of entries configured to store second snoop filter indications; and a cache controller configured to receive a transaction request including an address and to generate an index for accessing said first storage by performing a hash function on said address; wherein, said cache controller is further configured to selectively generate a snoop operation to said cache memory for said transaction request dependent upon a snoop filter indication stored in said first storage that corresponds to said address; wherein during a first mode of operation and in response to a cache memory access, said cache controller is configured to store said snoop filter indication in an entry of said first storage having an index equal to the hash value of an address associated with said cache line; and wherein during said first mode of operation, said cache controller is further configured to populate given entries of said second storage with said second snoop filter indications based on entries contained in said cache memory.