WARNING TRACK INTERRUPTION FACILITY

• US 20130185735A1
• Filed: 01/18/2012
• Published: 07/18/2013
• Est. Priority Date: 01/18/2012
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Farrell, Mark S., Gainey, Charles W. Jr., Kubala, Jeffrey P., Mulder, James H., Pierce, Bernard, Rogers, Robert R., Schmidt, Donald W.
• Granted Patent: US 8,850,450 B2
• Time in Patent Office: Days
• US Class Current: 719/318
• CPC Class Codes: G06F 13/24 using interrupt G06F13/32 takes precedence
• CPC Class Codes: G06F 2009/45579 I/O management, e.g. providing access to device drivers or storage
• CPC Class Codes: G06F 9/45533 Hypervisors; Virtual machine monitors
• CPC Class Codes: G06F 9/45558 Hypervisor-specific management and integration aspects
• CPC Class Codes: G06F 9/4881 Scheduling strategies for dispatcher, e.g. round robin, multi-level priority queues
• CPC Class Codes: G06F 9/4887 involving deadlines, e.g. rate based, periodic
• CPC Class Codes: G06F 9/5038 considering the execution order of a plurality of tasks, e.g. taking priority or time dependency constraints into consideration scheduling strategies G06F9/4881 and subgroups
• CPC Class Codes: G06F 9/526 Mutual exclusion algorithms
• CPC Class Codes: G06F 9/54 Interprogram communication
• CPC Class Codes: G06F 9/542 Event management; Broadcasting; Multicasting; Notifications

Abstract

A program (e.g., an operating system) is provided a warning that it has a grace period in which to perform a function, such as cleanup (e.g., complete, stop and/or move a dispatchable unit). The program is being warned, in one example, that it is losing access to its shared resources. For instance, in a virtual environment, a guest program is warned that it is about to lose its central processing unit resources, and therefore, it is to perform a function, such as cleanup.

Claims

1. A computer program product for facilitating processing in a computing environment, said computer program product comprising:

a computer readable storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method comprising;

providing by a first program to a second program a warning track facility installed indication indicating installation of a warning track facility within the computing environment, the warning track facility to provide to the second program a grace period to perform a first function;

providing by the first program to the second program a warning track notification;

based on the warning track notification, initiating by the second program the first function within the grace period; and

performing by the first program a second function subsequent to the grace period.

2. The computer program product of claim 1, wherein the warning track notification comprises an interruption in which shared resources assigned to the second program are released subsequent to termination of the grace period.

3. The computer program product of claim 2, wherein the first program gains access to the released shared resources in order to perform the second function.

4. The computer program product of claim 1, wherein the first program is a host program and the second program is a guest program, the guest program having access to shared resources of the computing environment during a timeslice provided to a guest central processing unit on which the guest program executes, the grace period being distinguishable from the timeslice.

5. The computer program product of claim 4, wherein the grace period prematurely terminates the timeslice.

6. The computer program product of claim 4, wherein the grace period provides a period in addition to the timeslice in which to perform the first function.

7. The computer program product of claim 6, wherein the grace period is taken from a next timeslice provided to the second program.

8. The computer program product of claim 1, wherein the first function comprises one of:

completing a dispatchable unit executing on a processor in which the second program executes;

or

making the dispatchable unit re-dispatchable on another processor of the computing environment.

9. The computer program product of claim 1, wherein the method further comprises indicating by the second program completion of the first function during the grace period.

10. The computer program product of claim 9, wherein the method further comprises providing an indication to the second program a next time the second program executes that the first function completed during the grace period.

11. A computer system for facilitating processing in a computing environment, said computer system comprising:

a memory; and

a processor in communications with the memory, wherein the computer system is configured to perform a method, said method comprising;

providing by a first program to a second program a warning track facility installed indication indicating installation of a warning track facility within the computing environment, the warning track facility to provide to the second program a grace period to perform a first function;

providing by the first program to the second program a warning track notification;

based on the warning track notification, initiating by the second program the first function within the grace period; and

performing by the first program a second function subsequent to the grace period.

12. The computer system of claim 11, wherein the warning track notification comprises an interruption in which shared resources assigned to the second program are released subsequent to termination of the grace period.

13. The computer system of claim 11, wherein the first program is a host program and the second program is a guest program, the guest program having access to shared resources of the computing environment during a timeslice provided to a guest central processing unit on which the guest program executes, the grace period being distinguishable from the timeslice.

14. The computer system of claim 13, wherein the grace period prematurely terminates the timeslice.

15. The computer system of claim 13, wherein the grace period provides a period in addition to the timeslice in which to perform the first function.

16. The computer system of claim 11, wherein the first function comprises one of:

completing a dispatchable unit executing on a processor in which the second program executes;

or

making the dispatchable unit re-dispatchable on another processor of the computing environment.

17. The computer system of claim 11, wherein the method further comprises:

indicating by the second program completion of the first function during the grace period; and

providing an indication to the second program a next time the second program executes that the first function completed during the grace period.

18-20. -20. (canceled)