Realtime multithreaded hot-plug control

• US 20070271404A1
• Filed: 05/16/2006
• Published: 11/22/2007
• Est. Priority Date: 05/16/2006
• Status: Abandoned Application

• Current Assignee: Sun Microsystems Incorporated (Oracle Corporation)
• Original Assignee: Sun Microsystems Incorporated (Oracle Corporation)
• Inventors: Dearth, Glenn A., Jay, Stephen A., Ervin, Joseph J., Rubin, Gyorgy, Lopresti, Michael V.
• Application Number:
  US11/435,234
• Publication Number:
  US 20070271404A1
• Time in Patent Office: Days
• US Class Current: 710/302
• CPC Class Codes: G06F 13/102 where the programme performs an interfacing function, e.g. device driver G06F13/105 takes precedence; scheduling within device drivers G06F9/52; contention policies within device drivers G06F9/4881
• CPC Class Codes: G06F 13/4081 Live connection to bus, e.g. hot-plugging current or voltage limitation during live insertion H02H9/004
• CPC Class Codes: G06F 2213/0024 Peripheral component interconnect [PCI]

Abstract

A method for controlling hot-plug behavior includes identifying a hot-plug event caused by a hot-plug device; generating hot-plug threads that execute a hot-plug operation; executing a finite state machine state sequence to regulate hot-plug threads involved in the hot-plug operation; and completing the hot-plug operation at the end of the finite state machine state sequence. A computer usable medium has computer readable program code embodied therein for causing a computer system to execute the method for controlling hot-plug behavior. A hot-plug control system for a computer system includes a hot-plug device; a set of hot-plug threads that regulate operations in the hot-plug device; and a finite state machine that controls execution of instructions using the set of threads.

Claims

1. A method for controlling hot-plug behavior comprising:

identifying a hot-plug event caused by a hot-plug device;

generating hot-plug threads that execute a hot-plug operation;

executing a finite state machine state sequence to regulate hot-plug threads involved in the hot-plug operation; and

completing the hot-plug operation at the end of the finite state machine state sequence.

2. The method of claim 1, further comprising executing hot-plug thread instructions over sleep and wake periods.

3. The method of claim 1, further comprising implementing a finite state machine using ACPI.

4. The method of claim 1, wherein the hot-plug device is a PCI module.

5. The method of claim 2, further comprising employing state sharing, which comprises:

a plurality of control states, wherein one thread has complete ownership of a control state; and

a plurality of ownership transfer states, wherein a plurality of threads have ownership of an ownership transfer state.

6. The method of claim 5, further comprising:

a wake mode of a thread, wherein the thread checks for ownership of a current state of the finite state machine state sequence; and

a sleep mode of a thread, wherein the thread is inactive.

7. The method of claim 6, the wake mode further comprising:

a non-ownership of the current state of the finite state machine state sequence by a thread, wherein the thread relinquishes control of the finite state machine; and

an ownership of the current state of the finite state machine state sequence by a thread, comprising;

performing of a control operation by the thread; and

updating of the current state.

8. The method of claim 1, the hot-plug operation further comprising:

notifying an OS of a hot-plug request;

informing a driver by the OS to complete operations; and

detaching the driver when operations are complete.

9. The method of claim 1, wherein timeout conditions cause the hot-plug operation to return to a well-known state.

10. A computer usable medium having computer readable program code embodied therein for causing a computer system to execute a method for controlling hot-plug behavior comprising:

identifying a hot-plug event caused by a hot-plug device;

generating hot-plug threads that execute a hot-plug operation;

executing a finite state machine state sequence to regulate hot-plug threads involved in the hot-plug operation; and

completing the hot-plug operation at the end of the finite state machine state sequence.

11. The computer usable medium of claim 10, the method executing hot-plug thread instructions over sleep and wake periods.

12. The computer usable medium of claim 11, the method employing state sharing, which comprises:

a plurality of control states, wherein one thread has complete ownership of a control state; and

a plurality of ownership transfer states, wherein a plurality of threads has ownership of an ownership transfer state.

13. The computer usable medium of claim 11, the method further comprising:

a wake mode of a thread, wherein the thread checks for ownership of a current state of the finite state machine state sequence; and

a sleep mode of a thread, wherein the thread is inactive.

14. The computer usable medium of claim 13, the wake mode further comprising:

a non-ownership of the current state of the finite state machine state sequence by a thread, wherein the thread relinquishes control of the finite state machine; and

an ownership of the current state of the finite state machine state sequence by a thread, comprising;

performing of a control operation by the thread; and

updating of the current state.

15. A hot-plug control system for a computer system comprising:

a hot-plug device;

a set of hot-plug threads that regulate operations in the hot-plug device; and

a finite state machine that controls execution of instructions using the set of threads.

16. The hot-plug control system of 15, further comprising a fault injection mechanism to validate the control logic of the finite state machine.

17. The hot-plug control system of 15, implementing tracing of execution flow of the hot-plug threads.

18. The hot-plug control system of 15, wherein the hot-plug device comprises a PCI module.

19. The hot-plug control system of 15, wherein the hot-plug system is multithreaded.

20. The hot-plug control system of 15 wherein the finite state machine is implemented using ACPI.