Hard real-time response

• US 20060150185A1
• Filed: 12/20/2004
• Published: 07/06/2006
• Est. Priority Date: 12/20/2004
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: McKenney, Paul E., Sarma, Dipankar
• Granted Patent: US 7,748,003 B2
• Time in Patent Office: Days
• US Class Current: 718/102
• CPC Class Codes: G06F 2209/483 Multiproc
• CPC Class Codes: G06F 9/4812 by interrupt, e.g. masked
• CPC Class Codes: G06F 9/4887 involving deadlines, e.g. rate based, periodic
• CPC Class Codes: G06F 9/5044 considering hardware capabilities

Abstract

A general purposed operating system is modified to support hard real-time processing of hard real-time tasks. At least one processing unit in the operating system is designated as a hard real-time processing unit to process hard real-time tasks, and at least one processing unit in the operating system is designated as a non-hard real-time processing unit to process non-hard real-time tasks and designated non-deterministic processing steps. Hard real-time tasks assigned to the non-hard real-time processing unit may be transferred to the hard real-time processing unit, and tasks assigned to the hard real-time processing unit that are about to execute a non-deterministic processing step may be transferred to the non-hard real-time processing unit.

Claims

1. A method for providing hard real-time services comprising:

categorizing at least two processing units in a system with a single general purpose shared-memory operating system;

designating at least one processing unit within said operating system as a hard real-time processing unit;

designating at least one processing unit within said operating system as a non-hard real-time processing unit;

forwarding a task from said hard real-time processing unit to said non-hard real-time processing unit upon determining that it is about to commence a non-deterministic operation; and

returning said task to said real-time processing unit upon completion of the non-deterministic operation.

2. The method of claim 1, wherein the step of designating at least one processor within said operating system as a hard real-time processing unit includes dynamically assigning said hard real-time processing unit based upon running a real-time task on said processing unit.

3. The method of claim 1, wherein the step of categorizing at least two processing units in a single general purpose shared-memory operating system includes virtual and non-virtual processing units.

4. The method of claim 1, further comprising encoding said task with a processing step having a category selected from a group consisting of:

a deterministic operation and a non-deterministic operation.

5. The method of claim 4, further comprising recognizing when said task is about to commence execution of a non-deterministic operation.

6. The method of claim 1, wherein said processing step is selected from a group consisting of:

a system call, an interrupt, a trap, an exception, and a user mode execution.

7. The method of claim 1, further comprising remotely performing RCU processing.

8. The method of claim 1, further comprising said real-time processing unit executing a real-time designated task.

9. The method of claim 1, further comprising determining said task is a real-time task that has been designated as non-forwardable to said non-hard real-tine processing unit, and flagging an error upon determining that said task is about to commence a non-real-time processing step.

10. A computer system comprising:

at least two processing units in said system with a single general purpose shared-memory operating system;

at least one of said processing units designated within said operating system as a hard real-time processing unit;

at least one of said processing units designated within said operating system as a non-hard real-time processing unit;

a manager adapted to forward a task from said hard real-time processing unit to said non-hard real-time processing unit in response to a determination that said task is about to commence a non-deterministic operation; and

said manager adapted to return said task to said real-time processing unit upon completion of said non-deterministic operation.

11. The system of claim 10, further comprising a processing unit manager adapted to dynamically assign said hard real-time processing unit responsive to execution of a real-time task on said hard real-time processing unit.

12. The system of claim 10, wherein said processing units are selected from a group consisting of:

a virtual processing unit and non-virtual processing unit.

13. The system of claim 10, further comprising a task manager adapted to encode said task with a processing step having a category selected from a group consisting of:

a deterministic operation, and a non-deterministic operation.

14. The system of claim 13, wherein said task manager is adapted to recognize when said task is about to commence execution of a non-deterministic operation.

15. The system of claim 10, wherein said processing step is selected from a group consisting of:

a system call, an interrupt, a trap, an exception, and a user mode execution.

16. The system of claim 10, further comprising an RCU process adapted to be remotely performed.

17. The system of claim 10, wherein said real-time processing unit is adapted to execute a real-time designated task.

18. The system of claim 10, further comprising a task manager adapted to determine if said task is a real-time task that has been designated as non-forwardable to said non-hard real-time processing unit, and flagging an error upon determining that said task is about to commence a non-deterministic operation.

19. An article comprising:

a computer readable signal bearing medium;

means in the medium for categorizing at least two processing units in a system with a single general purpose shared-memory operating system;

means in the medium for designating at least one of said processing units within said operating system as a hard real-time processing unit;

means in the medium for designating at least one of said processing units within said operating system as a non-hard real-time processing unit;

means in the medium for forwarding a task from said hard real-time processing unit to said non-hard real-time processing unit in response to a determination that said task is about to commence a non-deterministic operation; and

said task forwarding means adapted to return said task to said real-time processing unit upon completion of said non-deterministic operation.

20. The article of claim 19, wherein said medium is selected from a group consisting of:

a recordable data storage medium and a modulated carrier signal.

21. The article of claim 19, further comprising means in the medium for dynamically assigning said hard real-time processing unit responsive to execution of a real-time task on said hard real-time processing unit.

22. The article of claim 19, wherein said processing units are selected from a group consisting of:

a virtual processing unit and non-virtual processing unit.

23. The article of claim 19, further comprising means in the medium for encoding said task with a processing step having a category selected from a group consisting of:

a deterministic operation, and a non-deterministic operation.

24. The article of claim 23, wherein said task encoding means is adapted to recognize when said task is about to commence execution of a non-deterministic operation.

25. The article of claim 19 wherein said processing step is selected from a group consisting of:

a system call, an interrupt, a trap, an exception, and a user mode execution.

26. The article of claim 19, further comprising means in the medium for remotely performing an RCU process.

27. The article of claim 19, wherein said real-time processing unit is adapted to execute a real-time designated task.

28. The article of claim 19, further comprising means in the medium for determining if said task is a real-time task that has been designated as non-forwardable to said non-hard real-time processing unit, and flagging an error upon determining that said task is about to commence a non-deterministic operation.

29. A single general purpose shared-memory operation system comprising:

at least two processing units functioning within said system;

at least one of said processing units designated as a hard real-time processing unit;

at least one of said processing units designated as a non-hard real-time processing unit; and

a task adapted to be forward from said hard real-time processing unit to said non-hard real-time processing unit in response to a determination that said task is about to commence a non-deterministic operation, wherein said task is adapted to be return to said hard real-time processing unit upon completion of said non-deterministic operation.

30. A computer system comprising:

at least two processing units in said system with a single general purpose shared-memory operating system;

at least one of said processing units designated within said operating system as a hard real-time processing unit;

at least one of said processing units designated within said operating system as a non-hard real-time processing unit;

means for forwarding a task from said hard real-time processing unit to said non-hard real-time processing unit in response to a determination that said task is about to commence a non-deterministic operation; and

means for returning said task to said real-time processing unit upon completion of said non-deterministic operation.