Executing a general-purpose operating system as a task under the control of a real-time operating system

• US 8,555,285 B2
• Filed: 02/25/2004
• Issued: 10/08/2013
• Est. Priority Date: 08/26/2003
• Status: Expired due to Fees

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Sun, Zhitai, Hasegawa, Kenichi, Kato, Takeharu, Uchiyama, Toru
• Primary Examiner(s): Al Kawsar, Abdullah
• Assistant Examiner(s): Arcos, Caroline H
• Application Number:
  US10/784,944
• Publication Number:
  US 20050050541A1
• Time in Patent Office: 3,513 Days
• Field of Search: 718/102, 718/103, 718/105, 718/108, 718/100, 718/104
• US Class Current: 718/103
• CPC Class Codes: G06F 9/4881 Scheduling strategies for dispatcher, e.g. round robin, multi-level priority queues

Abstract

A task control computer program includes computer executable instructions which when executed by a computer, cause the computer to execute an operating system as a task. The computer is caused to perform determining whether there is an executable non-idle process under control of the operating system and changing a set priority of the operating system task to a priority higher than the primary priority of the operating system task when it is determined that there is an executable non-idle process with the specified time elapsed.

Claims

1. A non-transitory computer-readable recording medium that stores a task control computer program including computer executable instructions which when executed by a computer, cause the computer to execute an operation, comprising:

executing a General-Purpose operating system as a task under control of a Real-Time operating system;

determining whether a non-idle process is included in processes to be executed under control of the General-Purpose operating system based on a process identifier that indicates whether a process is the non-idle process or not and is stored in a process control block (PCB) of processes to be executed under control of the General-Purpose operating system, the non-idle process being a process waiting for execution under control of the General-Purpose operating system, other than an idle process executed when the General-Purpose operating system proceeds to an idle state; and

changing a priority of the task to a higher priority by reading the higher priority stored in a storage unit as a system parameter and setting the priority of the task to the higher priority when it is determined at the determining that the processes to be executed under control of the General-Purpose operating system include the non-idle process, the higher priority being set higher than a primary priority of the task to execute the General-Purpose operating system under control of which the non-idle process is executed, and

further changing priority of the task to the primary priority lower than the higher priority by reading the primary priority stored in the storage unit as a system parameter and setting the priority of the task to the primary priority after the General-Purpose operating system has been executed at the higher priority for a predetermined period of time, and

wherein a system call that executes the determining and the changing is implemented.

2. The non-transitory computer-readable recording medium that stores the task control computer program according to claim 1, wherein the determining comprises:

determining whether a schedule request for one of the processes to be executed under control of the operating system has been made to the operating system; and

determining whether an interruption request has been made to the operating system based on an interruption request flag set when an interruption to the operating system is required.

3. The non-transitory computer-readable recording medium that stores the task control computer program according to claim 2, wherein the determining whether the schedule request has been made to the General-Purpose operating system is based on a schedule request flag stored in the process control block of one of the processes to be executed under control of the operating system.

4. The non-transitory computer-readable recording medium that stores the task control computer program according to claim 1, wherein the primary priority of the task is changed to the higher priority when a predetermined period of time has elapsed after it is determined at the determining that the non-idle process waiting for the execution is included in the processes to be executed under control of the General-Purpose operating system.

5. The non-transitory computer-readable recording medium that stores the task control computer program according to claim 1, comprising:

wherein further changes the priority of the task to the primary priority of the task when a predetermined state of a resource is reached.

6. A task control apparatus, comprising:

a non-transitory storage device storing computer-readable instructions, which when executed by the task control apparatus causing a computer to execute a General-Purpose operating system as a task under control of a Real-Time operating system, execution of the instructions configuring the task control apparatus to include

a process control block (PCB) that stores a process identifier that indicates whether a process is a non-idle process or not;

a determining unit that determines whether the process is the non-idle process or not wherein the non-idle process is executable under control of the General-Purpose operating system based on the process identifier stored in the process control block (PCB) of processes to be executed under control of the General-Purpose operating system, wherein the non-idle process is a process waiting for execution under control of the General-Purpose operating system, other than an idle process executed when the General-Purpose operating system proceeds to an idle state; and

a changing unit that changes a priority of the task to a higher priority by reading the higher priority stored in a storage unit as a system parameter and setting the priority of the task to the higher priority when it is determined that the processes to be executed under control of the General-Purpose operating system include the non-idle process, the higher priority being set higher than a primary priority of the task to execute the General-Purpose operating system under control of which the non-idle process is executed, the task being executed under control of the Real-Time operating system, the changing unit further changes priority of the task to the primary priority lower than the higher priority by reading the primary priority stored in the storage unit as a system parameter and setting the priority of the task to the primary priority after the General-Purpose operating system has been executed at the higher priority for a predetermined period of time, and

wherein a system call that executes the determining and the changing is implemented.

7. A task control method for a computer comprising:

executing a General-Purpose operating system as a task under control of a Real-Time operating system;

determining whether processes to be executed under control of the General-Purpose operating system include a non-idle process based on a process identifier stored in a process control block (PCB) of processes to be executed under control of the General-Purpose operating system, the process identifier indicating whether a process is the non-idle process or not and the non-idle process is a process waiting for execution as the task under control of the General-Purpose operating system, other than an idle process executed when the General-Purpose operating system proceeds to an idle state; and

changing a priority of the task to a higher priority by reading the higher priority stored in a storage unit as a system parameter and setting the priority of the task to the higher priority when it is determined at the determining that the processes to be executed under control of the General-Purpose operating system include the non-idle process, the higher priority being set higher than a primary priority of the task to execute the General-Purpose operating system under control of which the non-idle process is executed, the task being executed under control of the Real-Time operating system; and

further changing priority of the task to the primary priority lower than the higher priority by reading the primary priority stored in the storage unit as a system parameter and setting the priority of the task to the primary priority after the General-Purpose operating system has been executed at the higher priority for a predetermined period of time, and

wherein a system call that executes the determining and the changing is implemented.