Apparatus and method for suspending and resuming software applications on a computer

• US 4,907,150 A
• Filed: 07/26/1988
• Issued: 03/06/1990
• Est. Priority Date: 01/17/1986
• Status: Expired due to Term

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Day, Michael N., Edrington, Jimmie D., Hanna, James T., Hunt, Gary T., Pancoast, Steven T., Arroyo, Ronald X.
• Primary Examiner(s): CLARK, DAVID
• Application Number:
  US07/225,570
• Time in Patent Office: 588 Days
• Field of Search: 364/200 MS File, 364/900 MS File, 371/12,14, 371/66
• US Class Current: 713/323
• CPC Class Codes: G05B 2219/34306 Power down, energy saving
• CPC Class Codes: G05B 2219/34365 After interrupt of operation, do other task and go on - resume operation
• CPC Class Codes: G06F 1/26 Power supply means, e.g. regulation thereof for memories G11C
• CPC Class Codes: G06F 1/30 Means for acting in the event of power-supply failure or interruption, e.g. power-supply fluctuations for resetting only G06F1/24
• CPC Class Codes: G06F 1/3203 Power management, i.e. event-based initiation of a power-saving mode
• CPC Class Codes: G06F 1/3246 by software initiated power-off
• CPC Class Codes: G06F 11/14 Error detection or correction of the data by redundancy in operation G06F11/16 takes precedence
• CPC Class Codes: G06F 9/461 Saving or restoring of program or task context
• CPC Class Codes: Y02P 70/10 Greenhouse gas [GHG] capture, material saving, heat recovery or other energy efficient measures, e.g. motor control, characterised by manufacturing processes, e.g. for rolling metal or metal working

Abstract

A method and apparatus for powering down a computer system while saving the state of the system at power down is disclosed. The system maintains the capability to suspend the execution of an application program operating on the system at any point and resuming execution of the application program at that same point at a later time. The time at which the system may be powered down and then powered back up again is totally arbitrary and depends only upon the user of the system. At the time the system is powered off, the contents of all active registers as well as the states of all I/O devices in the system are stored in a special save area of system memory. This special save area is provided with power during the suspended time in order to retain the state of the system at the time it was powered down. By using this special save suspend area, the main memory area of the system is available to any application programs independently of the system save memory requirements. Additionally, the system may be powered on and off under software control thereby providing the capability for unattended system operation using an alarm function.

Claims

1. In an information processing system including a central processor, memory, and a plurality of input-output devices, a method of controlling the operation of said information processing system comprising the steps of:

detecting the initiation of a powering-off sequence of said information processing system;

accessing system profile data stored within said memory to determine whether a resume mode is set;

saving, in response to said resume mode being set, the state of all memory locations, the state of said plurality of input-output devices, and all interrupt, register and display data in said memory; and

setting a system flag prior to the removal of power from said system in response to said saving step thereby suspending the operation of said information processing system.

2. The method according to claim 1 further comprises the steps of:

disabling all interrupts in said system in response to said detecting step;

performing a first checksum operation on said memory subsequent to said saving step; and

halting operation of each of said plurality of input-output devices.

3. The method according to claim 2 further includes the steps of:

detecting the application of power to said system;

determining whether said system is to be resumed in said saved states;

performing a second checksum operation on said memory in response to said determination that said system is to be resumed in said saved states;

comparing the results of said first and said second checksum operations;

restoring, in response to the results of said first checksum operation being equal to that of said second checksum operation, all memory locations, of each of said plurality of input-output devices, register and display devices to the states existing at the time said system was suspended; and

resuming operation of said system at the point at which it was suspended in response to said restoring step.

4. In an information processing system including a central processor on which an application program is executing, memory, and a plurality of input-output devices, a method of controlling the execution of said application program on said system comprising the steps of:

detecting the initiation of a powering-off sequence of said information processing system;

accessing system profile data stored within said memory to determine whether a resume mode is set;

saving, in response to said resume mode being set, the state of all memory locations, the state of said plurality of input-output devices, and all interrupt, register and display data in said memory; and

,

setting a system flag prior to the removal of power from said system in response to said saving step thereby suspending the execution of said application program on said system.

5. The method according to claim 4 further comprises the steps of:

disabling all interrupts in said system in response to said detecting step;

performing a first checksum operation on said memory subsequent to said saving step; and

halting operation of each of said plurality of input-output devices.

6. The method according to claim 5 further includes the steps of:

detecting the application of power to said system;

determining whether said system is to be resumed in said saved states;

performing a second checksum operation on said memory in response to said determination that said system is to be resumed in said saved states;

comparing the results of said first and said second checksum operations;

restoring, in response to the results of said first checksum operation being equal to that of said second checksum operation, all memory locations, each of said plurality of input-output devices, register and display devices to the states existing at the time said application program was suspended; and

resuming execution of said application program at the point at which said program was suspended in response to said restoring step.

7. The method according to claim 6 wherein said saved states are stored in a suspend area of said memory further includes the step of accessing said suspend area of said memory.

8. The method according to claim 7 further includes the step of disabling access to said suspend are prior to said resuming step.

9. The method according to claim 8 wherein said resuming step includes the steps of:

transmitting a resume call to an operating system program which controls said information processing system;

restoring a printer in said information processing system to the state which existed at the time said application program was suspended; and

updating the present time and date in response to a real time clock in said information processing system.

10. The method according to claim 4 wherein said saving step comprises the step of activating a suspend area of said memory for storing the state of said memory locations, the state of each of said plurality of input-output devices and all interrupt, register and display data.

11. The method according to claim 10 further includes the step of performing a checksum operation on said suspend area as well as on the remainder of said memory.

12. A system for controlling the execution of an application program on an information processing system comprising:

means for detecting the initiation of a powering-off sequence of said information processing system;

means, coupled to said detecting means, for accessing a system profile data stored within said information processing system to determine whether a resume mode is set;

means, coupled to said accessing means, for saving the state of all memory locations, the state of all input-output devices coupled to said system, and all interrupt, register and display data, in response to said resume mode being set; and

,

means for setting a system flag prior to the removal of power from said system in response to said saved states being stored in said saving means thereby suspending the execution of said application program on said system.

13. The system according to claim 12 further comprises:

means for disabling all interrupts in said system;

means, coupled to said saving means, for performing a first checksum operation on said saving means; and

means for halting operation of each of said plurality of input-output devices in response to a signal generated by said detecting means.

14. The system according to claim 13 further includes:

means for detecting the application of power to said system;

means for determining whether said operation of said system is to be resumed in said saved states;

means for performing a second checksum operation on said saving means in response to said determining means indicating that said system is to be resumed in said saved states;

means for comparing the results of said first and said second checksum operations;

means, responsive to said comparing means, for restoring the state of all memory locations, each of said input-output devices, register and display devices to the states existing at the time said application program was suspended; and

means for resuming execution of said application program at the point at which said application program was suspended.

15. The system according to claim 14 wherein said saved states are stored in a suspend said memory further includes means for accessing said suspend memory.

16. The system according to claim 15 further includes means for disabling access to said suspend memory in response to the restoring of said saved states.

17. The system according to claim 16 wherein said resuming means includes:

means for transmitting a resume call to an operating system program which controls said information processing system;

means for restoring a printer in said information processing system to the state which existed at the time said application program was suspended; and

means for updating the present time and date in response to a real time clock in said information processing system.

18. The system according to claim 12 wherein said saving means comprises a suspend memory and main memory and wherein said selected memory locations, the state of each of said input-output devices and all interrupt, register and display data are stored in said suspend memory.

19. The system according to claim 18 further includes means for performing a checksum operation on said suspend memory as well as on said main memory.