Merging demand load requests with prefetch load requests
AssigneeAdvanced Micro Devices, Inc.
InventorsSriram Srinivasan, Tarun Nakra
Life of this patent
Estimating the term…
Abstract
A processor includes a processing unit, a cache memory, and a central request queue. The central request queue is operable to receive a prefetch load request for a cache line to be loaded into the cache memory, receive a demand load request for the cache line from the processing unit, merge the prefetch load request and the demand load request to generate a promoted load request specifying the processing unit as a requestor, receive the cache line associated with the promoted load request, and forward the cache line to the processing unit.
Claims17
A processor, comprising:
- a processing unit;
- a cache memory;
- a central request queue operable to receive a prefetch load request for a cache line to be loaded into the cache memory, receive a demand load request for the cache line from the processing unit, merge the prefetch load request and the demand load request to generate a promoted load request specifying the processing unit as a requestor, receive the cache line associated with the promoted load request, and forward the cache line to the processing unit;
- and
- a processor request queue operable to store the demand load request, wherein the central request queue is operable to merge the prefetch load request and the demand load request to generate the promoted load request in the central request queue and is operable to delete the demand load request from the processor request queue in response to generating the promoted load request.
A method, comprising:
- receiving a prefetch load request for a cache line to be loaded into a cache memory;
- storing the prefetch load request in a central request queue;
- receiving a demand load request for the cache line from a processing unit;
- storing the demand load request in a processor request queue;
- merging the prefetch load request and the demand load request to generate a promoted load request specifying the processing unit as a requestor, wherein the merging of the prefetch load request and the demand load request comprises generating the promoted load request in the central request queue;
- deleting the demand load request from the processor request queue in response to generating the promoted load request;
- and
- receiving the cache line associated with the promoted load request and forwarding the cache line to the processing unit.
A non-transitory computer readable storage device encoded with data that, when implemented in a manufacturing facility, adapts the manufacturing facility to create a processor, comprising:
- a processing unit;
- a cache memory;
- a central request queue operable to receive a prefetch load request for a cache line to be loaded into a cache memory, receive a demand load request for the cache line from the processing unit, merge the prefetch load request and the demand load request to generate a promoted load request specifying the processing unit as a requestor, receive the cache line associated with the promoted load request, and forward the cache line to the processing unit;
- and
- a processor request queue operable to store the demand load request, wherein the central request queue is operable to merge the prefetch load request and the demand load request to generate the promoted load request in the central request queue and is operable to delete the demand load request from the processor request queue in response to generating the promoted load request.
Dependencies are inferred from the claim text.