Method and System For Spinlock Fault Recovery

• US 20120159242A1
• Filed: 12/16/2010
• Published: 06/21/2012
• Est. Priority Date: 12/16/2010
• Status: Active Grant

• Current Assignee: Wind River Systems Incorporated (Aptiv PLC)
• Original Assignee: Wind River Systems Incorporated (Aptiv PLC)
• Inventors: RICHARDSON, Raymond, Stults, Gregory
• Granted Patent: US 8,595,567 B2
• Time in Patent Office: Days
• US Class Current: 714/15
• CPC Class Codes: G06F 11/0715 in a system implementing multitasking multitasking per se G06F9/46
• CPC Class Codes: G06F 11/0724 in a multiprocessor or a multi-core unit multiprocessors per se G06F15/80
• CPC Class Codes: G06F 11/0757 by exceeding a time limit, i.e. time-out, e.g. watchdogs
• CPC Class Codes: G06F 11/0793 Remedial or corrective actions recovery from an exception in an instruction pipeline G06F9/3861; by retry G06F11/1402; for recovering from a failure of a protocol instance or entity H04L69/40
• CPC Class Codes: G06F 9/526 Mutual exclusion algorithms

Abstract

A method including requesting access to a resource governed by a spinlock; determining an allocation of the resource to a further requester; determining an expiration of a time limit for the spinlock, if the resource is allocated to the further requester; and initiating a fault recovery, if the time limit is expired.

Claims

1. A method, comprising:

requesting access to a resource governed by a spinlock;

determining an allocation of the resource to a further requester;

determining an expiration of a time limit for the spinlock, if the resource is allocated to the further requester; and

initiating a fault recovery, if the time limit is expired.

2. The method of claim 1, further comprising:

accessing the resource, if the resource is unallocated.

3. The method of claim 1, wherein the determining of the allocation of the resource comprises determining a status of the spinlock.

4. The method of claim 3, wherein the resource is determined to be allocated to the further requester if the status of the spinlock is TAKEN, and wherein the resource is determined not to be allocated to the further requester if the status of the spinlock is FREE.

5. The method of claim 2, wherein the accessing of the resource comprises changing a status of the spinlock from a FREE status to a TAKEN status.

6. The method of claim 1, wherein the initiating of the fault recovery comprises changing a status of the spinlock from a TAKEN status to a FAULTED status.

7. The method of claim 1, further comprising:

returning an error, if a status of the spinlock is FAULTED.

18. The non-transitory computer-readable storage medium of claim 7, wherein the resource is determined to be allocated to the further requester if the status of the spinlock is TAKEN, and wherein the resource is determined not to be allocated to the further requester if the status of the spinlock is FREE.

8. A system, comprising:

a resource;

a spinlock governing access to the resource; and

a plurality of takers for accessing the resource,

wherein, when a first taker requests access to the resource, the first taker;

determines whether a second taker is using the resource;

determines, if the second taker is using the resource, whether a time limit relating to the spinlock has been exceeded; and

initiates a fault recovery, if the time limit has been exceeded.

9. The system of claim 8, wherein the first taker accesses the resource, if the second taker is not using the resource.

10. The system of claim 8, wherein the determining of whether the second taker is using the resource comprises determining a status of the spinlock.

11. The system of claim 10, wherein the first taker determines that the second taker is using the resource if the status of the spinlock is TAKEN, and wherein the first taker determines that the second taker is not using the resource if the status of the spinlock is FREE.

12. The system of claim 9, wherein the accessing of the resource comprises changing a status of the spinlock from a FREE status to a TAKEN status.

13. The system of claim 8, wherein the initiating of the fault recovery comprises changing a status of the spinlock from a TAKEN status to a FAULTED status.

14. The system of claim 8, wherein the first taker returns an error if a status of the spinlock is FAULTED.

15. A non-transitory computer-readable storage medium storing a set of instructions executable by a processor, the set of instructions being operable to:

request access to a resource governed by a spinlock;

determine an allocation of the resource to a further requester;

determine an expiration of a time limit for the spinlock, if the resource is allocated to the further requester; and

initiate a fault recovery, if the time limit is expired.

16. The non-transitory computer-readable storage medium of claim 15, wherein the set of instructions is further operable to:

access the resource, if the resource is unallocated.

17. The non-transitory computer-readable storage medium of claim 15, wherein the determining of the allocation of the resource comprises determining a status of the spinlock.

19. The non-transitory computer-readable storage medium of claim 16, wherein the accessing of the resource comprises changing a status of the spinlock from a FREE status to a TAKEN status.

20. The non-transitory computer-readable storage medium of claim 15, wherein the initiating of the fault recovery comprises changing a status of the spinlock from a TAKEN status to a FAULTED status.

21. The non-transitory computer-readable storage medium of claim 15, wherein the set of instructions is further operable to:

return an error, if a status of the spinlock is FAULTED.