Reduction of interrupts in remote procedure calls

• US 20020078285A1
• Filed: 12/14/2000
• Published: 06/20/2002
• Est. Priority Date: 12/14/2000
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Hofstee, Harm Peter, Nair, Ravi
• Granted Patent: US 6,865,631 B2
• Time in Patent Office: Days
• US Class Current: 710/260
• CPC Class Codes: G06F 13/24 using interrupt G06F13/32 takes precedence

Abstract

A method and system for executing one or more remote procedure calls. In one embodiment, a method comprises the step of a processing unit issuing a plurality of commands to a corresponding DMA controller. One or more commands of the plurality of commands issued by the processing unit are to copy attached processing unit instructions associated with one or more Attached Processing Unit'"'"'s (APU'"'"'s) and data associated with the attached processing unit instructions from the shared memory to one or more APU'"'"'s. The attached processing unit instructions may include instructions that enable the associated one or more APU'"'"'s to perform one or more particular operations on the data. The method further comprises the DMA controller issuing an indication to the one or more APU'"'"'s to perform the one or more operations on the data associated with the attached processing unit instructions. Instead of having the particular APU that completed its operation notify the corresponding processing unit of its completion of the operation, the DMA controller polls a status line of each of the one or more attached processing units to determine if any of the one or more attached processing units completed its operation. The DMA controller then copies the results of the operations after each of the one or more attached processing units completes its operation.

Claims

1. A system comprising:

a shared memory; and

a plurality of processing elements coupled to said shared memory, wherein each of said plurality of processing elements comprises a processing unit, a direct memory access controller and a plurality of attached processing units, wherein said direct memory access controller is configured to receive a plurality of commands from a corresponding processing unit to be executed during one or more remote procedure calls, wherein each of said plurality of attached processing units in each of said plurality of processing elements does not interrupt said corresponding processing unit upon completion of each of said one or more remote procedure calls.

2. The system as recited in claim 1, wherein said direct memory access controller in each of said plurality of processing elements comprises a plurality of first level queues for storing said plurality of commands issued by said corresponding processing unit.

3. The system as recited in claim 2, wherein each of said plurality of first level queues are configured to store one or more commands of said plurality of commands associated with a different attached processing unit.

4. The system as recited in claim 2, wherein said plurality of commands comprise a first instruction to copy attached processing unit instructions associated with a particular attached processing unit from said shared memory to said particular attached processing unit, wherein said plurality of commands comprise a second instruction to copy data associated with said attached processing unit instructions from said shared memory to said particular attached processing unit.

5. The system as recited in claim 4, wherein said attached processing unit instructions associated with said particular attached processing unit comprise instructions that enable said particular attached processing unit to perform a particular operation on said data associated with said attached processing unit instructions associated with said particular attached processing unit.

6. The system as recited in claim 5, wherein said plurality of commands comprise a third instruction to copy the results of said particular operation to said shared memory.

7. The system as recited in claim 4, wherein said first and second instructions to copy attached processing unit instructions and data associated with said attached processing unit instructions are requests to copy one or more lines of memory in said shared memory to said particular attached processing unit.

8. The system as recited in claim 2, wherein said direct memory access controller comprises a second queue, wherein said plurality of commands in said plurality of first queues are merged in said second queue.

9. The system as recited in claim 8, wherein said direct memory access controller comprises a third queue, wherein said third queue expands said merged plurality of commands stored in said second queue into single line instructions.

10. The system as recited in claim 9, wherein said direct memory access controller executes said expanded merged plurality of commands stored in said third queue without bank conflicts.

11. The system as recited in claim 5, wherein said direct memory access controller is configured to poll a status line of each of said plurality of attached processing units to determine if any of said plurality of attached processing units completed its operation during said one or more remote procedure calls.

12. The system as recited in claim 1, wherein said direct memory access controller is configured to interrupt said corresponding processing unit at a synchronization point, wherein said synchronization point occurs after said one or more remote procedure calls are performed.

14. The system as recited in claim 13, wherein said direct memory access controller in each of said plurality of processing elements comprises a plurality of first level queues for storing said plurality of commands issued by said corresponding processing unit.

15. The system as recited in claim 14, wherein each of said plurality of first level queues are configured to store one or more commands of said plurality of commands associated with a different attached processing unit.

16. The system as recited in claim 14, wherein said plurality of commands comprise a first instruction to copy attached processing unit instructions associated with a particular attached processing unit from said shared memory to said particular attached processing unit, wherein said plurality of commands comprise a second instruction to copy data associated with said attached processing unit instructions from said shared memory to said particular attached processing unit.

17. The system as recited in claim 16, wherein said attached processing unit instructions associated with said particular attached processing unit comprise instructions that enable said particular attached processing unit to perform a particular operation on said data associated with said attached processing unit instructions associated with said particular attached processing unit.

18. The system as recited in claim 17, wherein said plurality of commands comprise a third instruction to copy the results of said particular operation to said shared memory.

19. The system as recited in claim 16, wherein said first and second instructions to copy attached processing unit instructions and data associated with said attached processing unit instructions are requests to copy one or more lines of memory in said shared memory to said particular attached processing unit.

20. The system as recited in claim 14, wherein said direct memory access controller comprises a second queue, wherein said plurality of commands in said plurality of first queues are merged in said second queue.

21. The system as recited in claim 20, wherein said direct memory access controller comprises a third queue, wherein said third queue expands said merged plurality of commands stored in said second queue into single line instructions.

22. The system as recited in claim 21, wherein said direct memory access controller executes said expanded merged plurality of commands stored in said third queue without bank conflicts.

23. The system as recited in claim 13, wherein said direct memory access controller is configured to interrupt said corresponding processing unit at a synchronization point, wherein said synchronization point occurs after said one or more remote procedure calls are performed.

25. The method as recited in claim 24, wherein said attached processing unit instructions enable said particular attached processing unit to perform said particular operation.

26. The method as recited in claim 24, wherein said indication to start said particular operation on said data is issued from said direct memory access controller to said particular attached processing unit.

27. The method as recited in claim 24 further comprising the step of:

interrupting said processing unit at a synchronization point, wherein said synchronization point occurs after said one or more remote procedure calls are performed.

28. The method as recited in claim 24, wherein said direct memory access controller comprises a plurality of first level queues for storing said plurality of commands.

29. The method as recited in claim 27, wherein each of said plurality of first level queues are configured to store one or more commands of said plurality of commands associated with a different attached processing unit.

30. The method as recited in claim 28, wherein said direct memory access controller comprises a second queue, wherein said plurality of commands in said plurality of first level queues are merged in said second queue.

31. The method as recited in claim 24, wherein said first and second instructions to copy attached processing unit instructions and data associated with said attached processing unit instructions are requests to copy one or more lines in said memory to said particular attached processing unit.

32. The method as recited in claim 30, wherein said direct memory access controller comprises a third queue, wherein said third queue expands said merged plurality of commands stored in said second queue into single line instructions.

33. The method as recited in claim 32, wherein said direct memory access controller executes said expanded merged plurality of commands stored in said third queue without bank conflicts.

34. The method as recited in claim 28, wherein said direct memory access controller comprises a second queue, wherein said plurality of commands in said plurality of first queues are expanded in said second queue.

35. The method as recited in claim 34, wherein said direct memory access controller comprises a third queue, wherein said third queue merges said expanded plurality of commnands stored in said second queue into single line instructions.

36. The method as recited in claim 35, wherein said direct memory access controller executes said expanded merged plurality of commands stored in said third queue without bank conflicts.

13. A system comprising:

a shared memory; and

a plurality of processing elements coupled to said shared memory, wherein each of said plurality of processing elements comprises a processing unit, a direct memory access controller and a plurality of attached processing units, wherein said direct memory access controller is configured to receive a plurality of commands from a corresponding processing unit to be executed during one or more remote procedure calls, wherein said direct memory access controller is configured to poll a status line of each of said plurality of attached processing units to determine if any of said plurality of attached processing units completed its operation during said one or more remote procedure calls.

24. A method for executing one or more remote procedure calls comprising the steps of:

issuing a plurality of commands by a processing unit to a direct memory access controller to be executed during one or more remote procedure calls, wherein said plurality of commands comprise a first instruction to copy attached processing unit instructions associated with a particular attached processing unit from a memory to said particular attached processing unit, wherein said plurality of commands comprise a second instruction to copy data associated with said attached processing unit instructions from said memory to said particular attached processing unit;

issuing to said particular attached processing unit an indication to start a particular operation on said data associated with said particular attached processing unit instructions; and

polling a status line of each of a plurality of attached processing units to determine if any of said plurality of attached processing units completed its particular operation;

wherein said plurality of attached processing units do not interrupt said processing unit upon completion of each of said one or more remote procedure calls.