US Patent 8645634 Zero-copy data sharing by cooperating asymmetric coprocessors

One embodiment of the present invention sets forth a technique for reducing the copying of data between memory allocated to a primary processor and a coprocessor is disclosed. The system memory is aliased as device memory to allow the coprocessor and the primary processor to share the same portion of memory. Either device may write and/or read the shared portion of memory to transfer data between the devices rather than copying data from a portion of memory that is only accessible by one device to a different portion of memory that is only accessible by the other device. Removal of the need for explicit primary processor memory to coprocessor memory and coprocessor memory to primary processor memory copies improves the performance of the application and reduces physical memory requirements for the application since one portion of memory is shared rather than allocating separate private portions of memory.