Patent ID: 8275917

Claim:
A method, in a data processing system, comprising: performing, using a first device in the data processing system, an operation on a shared buffer region, wherein the first device is a first synergistic processing unit; writing, by the first device, a pointer update to a first register in the first device, wherein the pointer update is an update to one of a head pointer or a tail pointer of the shared buffer region; writing, by the first device, the pointer update to a signal notification channel associated with a second device in the data processing system, wherein the second device is a second synergistic processing unit; updating, by the second device, a pointer stored in a second register in the second device with the pointer update in response to the pointer update being written to the signal notification channel by the first device; determining, by either the first device or the second device, whether the shared buffer region is full; responsive to the first device determining that the shared buffer region is full, entering, by the first device, a low-power consumption waiting state waiting for a predetermined amount of storage space to be freed in the shared buffer region before additional data may be written to the shared buffer region; responsive to the second device determining that the shared buffer region is full, entering, by the second device, the low-power consumption waiting state waiting for the predetermined amount of storage space to be freed in the shared buffer region before the additional data may be written to the shared buffer region; wherein entering the first device in the low-power consumption waiting state comprises placing the signal notification channel in a blocking mode of operation in which the first device's normal operation is blocked and the first device waits in a low-power consumption waiting state; and wherein entering the second device in the low-power consumption waiting state comprises placing the signal notification channel in a blocking mode of operation in which the second device's normal operation is blocked and the second device waits in the low-power consumption waiting state.