Multi OS configuration method and computer system

• US 20010016879A1
• Filed: 04/18/2001
• Published: 08/23/2001
• Est. Priority Date: 09/12/1997
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Ohno, Hiroshi, Shibata, Takashi, Arai, Toshiaki, Inoue, Taro, Sekiguchi, Tomoki, Kaneko, Shigenori
• Granted Patent: US 6,711,605 B2
• Time in Patent Office: Days
• US Class Current: 719/319
• CPC Class Codes: G06F 11/261 by simulating additional hardware, e.g. fault simulation
• CPC Class Codes: G06F 9/45537 Provision of facilities of other operating environments, e.g. WINE I/O emulation G06F13/105
• CPC Class Codes: G06F 9/4843 by program, e.g. task dispatcher, supervisor, operating system

Abstract

A computer system of a multi-operation-system (multi-OS) has a main memory having a memory area for a first OS and a memory area for a second OS, both the areas being independent from each other, and a plurality of I/O devices divisionally allocated to the first OS and the second OS. The first OS is loaded in the first OS memory area, and thereafter when the first OS is operated, the second OS is loaded in the second OS memory area and initialized. When the first OS is operated, the first OS hardware resources and the second OS hardware resources are registered by the first OS. Thereafter when the first OS is operated, the first OS inhibits the registration of an interrupt number already allocated to the second OS I/O device. In response to an interrupt request from a second OS I/O device, the second OS starts operating.

Claims

1. A multi-operating-system (multi-OS) configuration method for a computer system, comprising the steps of:

reserving a hardware resource when a first OS is set up, for another OS;

storing a common interrupt process program in a common area of a physical memory shared by all OSs;

scheduling an execution of each OS by said common interrupt process program; and

running a plurality of OSs on a single computer without any emulation software and hardware for a privilege instruction to be executed by each OS.

2. A multi-OS configuration method according to

claim 1

, further comprising the steps of:

reserving the hardware resource for the other OS (second OS) when the first OS is initialized, in order not to allow the first OS to access the hardware resource after the initialization of the first OS;

loading the second OS in a reserved area of the physical memory and activating the second OS in a virtual address space different from a virtual address space of the first OS;

setting a partial kernel area of the first OS so as to be shared by the second OS; and

modifying a data structure of the first OS in order not to allow the first OS to disable an external interrupt to be received by the second OS.

3. A multi-OS configuration method according to

claim 1

, further comprising the steps of:

determining which OS processes a captured interrupt, in accordance with an interrupt factor;

calling a module of the second OS from the first OS; and

resuming a process by the first OS when a process by the second OS is completed, to thereby run two OSs on a single computer.

4. A multi-OS configuration method according to

claim 1

, further comprising the steps of:

notifying a halt of the first OS caused by an unrecoverable fault to the other OS (second OS);

permitting an interrupt by a device managed by the second OS at the halt of the first OS; and

judging when a process by the second OS is completed whether the first OS is in a halt, and if in a halt, waiting for an interrupt,

to thereby continue an operation of the second OS even if the first OS halts.

5. A multi-OS configuration method according to

claim 3

, further comprising the steps of:

notifying a halt of the first OS caused by an unrecoverable fault to the other OS (second OS);

permitting an interrupt by a device managed by the second OS at the halt of the first OS; and

judging when a process by the second OS is completed whether the first OS is in a halt, and if in a halt, waiting for an interrupt,

to thereby continue an operation of the second OS even if the first OS halts.

6. A multi-OS configuration method according to

claim 1

, further comprising the step of:

preparing a kernel object file of the first OS in a dedicated area of the physical memory, the kernel object file storing instructions and data shared by the first OS and the other OS (second OS), searching the dedicated area of the kernel object file of the first OS when the second OS is. set up, and storing only the searched dedicated area in the common area.

7. A multi-OS configuration method according to

claim 5

, further comprising the step of:

preparing a kernel object file of the first OS in a dedicated area of the physical memory, the kernel object file storing instructions and data shared by the first OS and the other OS (second OS), searching the dedicated area of the kernel object file of the first OS when the second OS is set up, and storing only the searched dedicated area in the common area.

8. A multi-OS configuration method according to

claim 1

, further comprising the steps of:

recording an interrupt by a device managed by the first OS, the interrupt being issued while the other OS (second OS) is executed;

starting a process of the interrupt issued while the second OS is executed, when a process by the second OS is completed and a control is passed to the first OS; and

starting a process of an interrupt by a device managed by the second OS by immediately switching an OS even if the first OS is under execution,

to thereby schedule to operate the first OS only during an idle state of the second OS and to shorten a response time to an interrupt issued by the device managed by the second OS.

9. A multi-OS configuration method according to

claim 7

, further comprising the steps of:

recording an interrupt by a device managed by the first OS, the interrupt being issued while the other OS (second OS) is executed;

starting a process of the interrupt issued while the second OS is executed, when a process by the second OS is completed and a control is passed to the first OS; and

starting a process of an interrupt by a device managed by the second OS by immediately switching an OS even if the first OS is under execution,

to thereby schedule to operate the first OS only during an idle state of the second OS and to shorten a response time to an interrupt issued by the device managed by the second OS.

10. A multi-OS configuration method according to

claim 1

, wherein:

the computer system has a plurality of processors and a unit for notifying an interrupt from an external device to a specific processor or a processor group; and

the method further comprises the steps of;

reserving a processor when the first OS is initialized, for the other OS (second OS);

setting up the second OS by the reserved processor; and

notifying an interrupt from the external device to a processor or a processor group on which an OS managing the external device runs.

11. A multi-OS configuration method according to

claim 7

, wherein:

the computer system has a plurality of processors and a unit for notifying an interrupt from an external device to a specific processor or a specific processor group; and

the method further comprises the steps of;

reserving a processor when the first OS is initialized, for the other OS (second OS);

setting up the second OS by the reserved processor; and

notifying an interrupt from the external device to a processor or a processor group on which an OS managing the external device runs.

12. A multi-OS configuration method according to

claim 2

, wherein a plurality of files are read when the first OS is set up, ana a hardware dependent process file separated from a core portion of the kernel area of the first OS is modified.

13. A multi-operation-system (multi-OS) configuration method for a computer system comprising the steps of:

allocating a memory area for a first OS and a memory area for a second OS in a main memory of the computer system, both the areas being independent from each other;

assigning hardware resources of the computer system divisionally to the first OS and the second OS;

loading the first OS in the first OS memory area;

registering the first OS hardware resources and the second OS hardware resources when the first OS is set up;

loading the second OS in the second OS memory area and initializing the second OS, when the first OS is operated; and

operating the second OS in response to an interrupt request from any one of the second OS hardware resources.

14. A multi-OS configuration method according to

claim 13

, further comprising the steps of:

allocating a common memory area shared by the first OS and the second OS to the main memory; and

storing an address of an interrupt handler for each of the hardware resources in the common memory area,

wherein in response to an interrupt request from any one of the hardware resources, the computer system refers to the common memory area and identifies the address of the interrupt handler corresponding to the interrupt request to thereafter execute a requested interrupt process.

15. A multi-OS configuration method according to

claim 13

, wherein the hardware resources are each assigned a different interrupt number, and an interrupt by the first OS with respect to the hardware resource assigned the interrupt number for the second OS is disabled when the second OS is initialized.

16. A computer system of a multi-operation-system (multi-OS) configuration, comprising:

a main memory having a storage area for a first OS and a memory area for a second OS, both the areas being independent from each other; and

a plurality of hardware resources divisionally allocated to the first OS and the second OS,

wherein;

the first OS is loaded in the first OS memory area;

the first OS hardware resources and the second OS hardware resources are registered by the first OS when the first OS is set up;

the second OS is loaded in the second OS memory area and initializing by the first OS when the first OS is operated; and

the computer system operates the second OS in response to an interrupt request from any one of the second OS hardware resources, and the first OS request.

17. A computer system according to

claim 16

, wherein:

the main memory includes a common memory area shared by the first OS and the second OS, and an address of an interrupt handler for each of the hardware resources is stored in the common memory area; and

in response to an interrupt request from any one of the hardware resources, the computer system refers to the common memory area and identifies the address of the interrupt handler corresponding to the interrupt request to thereafter execute a requested interrupt process.

18. A computer system according to claim lo, wherein the hardware resources are each assigned a different interrupt number, the computer system further comprises an interrupt controller that is managed with an interrupt mask table of the first OS, and when the second OS is initialized, initialization done by the first OS modifies the interrupt inhibition table to disable an interrupt by the first OS with respect to the hardware resource assigned the interrupt number for the second OS.