Energy Efficient Implementation Of Read-Copy Update For Light Workloads Running On Systems With Many Processors
First Claim
1. In a multiprocessor computing system having two or more processors operatively coupled to one or more memory devices and implementing a read-copy update (RCU) subsystem, a method for determining if a processor may be placed in low power state, comprising:
- determining whether said processor has any RCU callbacks that are ready for invocation or said RCU subsystem requires grace period advancement processing from said processor; and
placing said processor in a low power state if either;
a first condition holds wherein said processor has one or more pending RCU callbacks, but does not have any RCU callbacks that are ready for invocation and said RCU subsystem does not require grace period advancement processing from said processor;
ora second condition holds wherein said processor does not have any pending RCU callbacks.
1 Assignment
0 Petitions
Accused Products
Abstract
A technique for determining if a processor in a multiprocessor system implementing a read-copy update (RCU) subsystem may be placed in low power state. The technique may include determining whether the processor has any RCU callbacks that are ready for invocation or the RCU subsystem requires grace period advancement processing from the processor. The processor may be placed in a low power state if either (1) a first condition holds wherein the processor has one or more pending RCU callbacks, but does not have any RCU callbacks that are ready for invocation and the RCU subsystem does not require grace period advancement processing from the processor, (2) a second condition holds wherein the processor does not have any pending RCU callbacks.
-
Citations
21 Claims
-
1. In a multiprocessor computing system having two or more processors operatively coupled to one or more memory devices and implementing a read-copy update (RCU) subsystem, a method for determining if a processor may be placed in low power state, comprising:
-
determining whether said processor has any RCU callbacks that are ready for invocation or said RCU subsystem requires grace period advancement processing from said processor; and placing said processor in a low power state if either; a first condition holds wherein said processor has one or more pending RCU callbacks, but does not have any RCU callbacks that are ready for invocation and said RCU subsystem does not require grace period advancement processing from said processor;
ora second condition holds wherein said processor does not have any pending RCU callbacks. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. A multiprocessor system, comprising:
-
two or more processors; a memory coupled to said processors, said memory including a computer useable medium tangibly embodying at least one program of instructions executable by said processors to implement a read-copy update (RCU) subsystem and to perform operations for determining if a processor may be placed in low power state, said operations comprising; determining whether said processor has any RCU callbacks that are ready for invocation or said RCU subsystem requires grace period advancement processing from said processor; and placing said processor in a low power state if either; a first condition holds wherein said processor has one or more pending RCU callbacks, but does not have any RCU callbacks that are ready for invocation and said RCU subsystem does not require grace period advancement processing from said processor;
ora second condition holds wherein said processor does not have any pending RCU callbacks. - View Dependent Claims (9, 10, 11, 12, 13, 14)
-
-
15. A computer program product, comprising:
-
one or more machine-useable storage media; program instructions provided by said one or more media for programming a multiprocessor data processing platform to implement a read-copy update (RCU) subsystem and to perform operations for determining if a processor may be placed in low power state, said operations comprising; determining whether said processor has any RCU callbacks that are ready for invocation or said RCU subsystem requires grace period advancement processing from said processor; and placing said processor in a low power state if either; a first condition holds wherein said processor has one or more pending RCU callbacks, but does not have any RCU callbacks that are ready for invocation and said RCU subsystem does not require grace period advancement processing from said processor;
ora second condition holds wherein said RCU subsystem does require grace period advancement processing from said processor, but said processor does not have any pending RCU callbacks. - View Dependent Claims (16, 17, 18, 19, 20, 21)
-
Specification