Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
121 words
Cache line entry replacement control for a cache directory in each of plural central processors (CPs) in a multiprocessor (MP), in which each respective CP makes storage requests to a local cache directory, each CP causing a cross-interrogation request to all other CPs in the MP upon a CP request having a cache miss, each respective CP comprising: means for generating a task identifier (TID) associated with a program executing in the respective CP, means for communicating a task identifier active in the respective CP to the other CPs in the MP, cache replacement selection means in the respective CP for enabling the replacement of a cache entry associated with the task identifier of another CP provided by the communicating means.
Claim 2
Dependent Claim
121 words
Cache line entry replacement control for a cache directory in each of plural central processors (CPs) in a multiprocessor (MP), in which each respective CP makes storage requests to a local cache directory, each CP causing a cross-interrogation request to all other CPs in the MP upon a CP request having a cache miss, each respective CP comprising: means for generating a task identifier (TID) associated with a program executing in the respective CP, means for communicating a task identifier active in the respective CP to the other CPs in the MP, cache replacement selection means in the respective CP for enabling the replacement of a cache entry associated with the task identifier of another CP provided by the communicating means.
Claim 3
Dependent Claim
52 words
Cache line entry replacement control for an MP as defined in claim 1, further comprising: means for inserting the TID of the respective CP into an entry in the local cache directory accessed by a request from the respective CP, each valid entry in the local cache directory having an entry TID.
Claim 4
Dependent Claim
59 words
Cache line entry replacement control for a MP as defined in claim 2, further comprising: a task identifier (TID) register for containing a TID representing a remote task executing in another CP in the MP, means for loading the TID register with a remote TID from another CP when another CP makes a cross-interrogation request to the communicating means.
Claim 5
Dependent Claim
105 words
Cache line entry replacement control for an MP as defined in claim 3, further comprising: means for detecting a cache miss by a CP request in the local cache directory, a class of entries being accessed in the directory at the time of the cache miss, means for entry comparing any remote TID in the TID register with the entry TID in each entry in the class of entries being accessed, means for making an accessed local directory entry a TID candidate for replacement when the entry comparing means finds the accessed entry contains a TID equal to a remote TID in the TID register.
Claim 6
Dependent Claim
73 words
Cache line entry replacement control for a MP as defined in claim 4, further comprising: means for remote comparing a local TID associated with a program executing on the respective CP with any remote TID in the TID register, means for resetting the TID register whenever the TID comparing means finds the local TID is equal to the remote TID in the TID register to invalidate any TID content in the TID register.
Claim 7
Dependent Claim
43 words
Cache line entry replacement control for an MP as defined in claim 5, further comprising: means for enabling the reset means on each cache hit by a CP request to the local cache directory and on each cross-interrogation request by the communicating means.
Claim 8
Dependent Claim
71 words
Cache line entry replacement control for an MP as defined in claim 6, further comprising: means for detecting any accessed cache directory entry indicating an invalid line in the local cache having a cache miss, means for replacing any TID candidate if the detecting means does not detect any entry for an invalid line, but the replacing means first replacing any entry for an invalid line determined by the detecting means.
Claim 9
Dependent Claim
30 words
Cache line replacement control for an MP as defined in claim 7, in which the local TID for each CP comprises: a segment table origin (STO) in a control register.
Claim 10
Dependent Claim
44 words
Cache line replacement control for an MP as defined in claim 7, in which the local TID for each CP comprises: a segment table origin (STO) in a control register and a storage protect key in a program status word (PSW) for each CP.