JPH0378034A - Program parallel execution device - Google Patents

Abstract

PURPOSE:To facilitate the parallel processing of a single-task operating system by saving registers in the dedicated area of a task when a program being executed is interrupted at a request from the task. CONSTITUTION:When the program being executed is interrupted at the request from the task 1, all registers of a task control table except the stack pointer 14 of the task 1 are saved in the stack area. Then the pointer register is saved in the stack pointer of another task of the control table. At this time, when the task 1 waits for an event, the corresponding task status 13 of the control table is disabled and necessary data are set to various other data 15. When the task 1 is executed, the pointer 14 of the control table is reloaded in a register and then other registers in the stack area are reloaded. Consequently, the parallel processing of the single-task operating system is facilitated.

Description

[Detailed description of the invention]

[Technical Field of the Invention J This invention is directed to a computer device running under a program generally referred to as a single-task O3 (operating system). Concerning the construction of O8. [Background of the Invention] Currently, single task O8 is widely used, and as the name suggests, the programs created there are executed in series. Also, although they appear to be parallel, one cannot be executed until the other finishes. moreover,
There are some that use this O8 to operate in parallel, but they are switched on a job-by-job basis and can only handle limited events. It is not possible to organically combine and run a program in parallel and efficiently. In addition, there are many monitor programs that have more dynamic real-time performance than the present invention, but they operate under unique environments.
It is difficult to use for program development that does not require real-time performance. [Object of the Invention] Therefore, an object of the present invention is to easily implement parallel processing-multitasking when a user wants to perform parallel operations even though real-time performance is not required in a single-task OS computer device that is familiar to the user. The object of the present invention is to provide a device that can configure processing. [Configuration and Effects of the Invention] The present invention provides basic functions of conventional real-time monitors - program interruption, event detection, task scheduling,
Although the system has functions such as resuming program execution, a scanning loop is used to detect the event even under a single task O8. The portion of the program that is being executed is interrupted based on a request from a task, and is done by saving the state of the task, that is, the register, to an area dedicated to that task. Resuming is performed by restoring the data in the dedicated area for that task. It is easy to start executing a task for the first time by regarding the start point of the task as the interruption point. Event detection involves checking for each event, such as whether data has been input or output, using a scanning loop for all events, and if a condition has occurred for the task to resume the next process. Make the task executable. To schedule a task, check the task management table and
Select tasks that are executable. When there are several tasks that can be executed, the one with the highest priority level is usually selected. Also, if the processing of a certain task takes a long time, either by request from the task or after processing for a certain period of time,
Execution of this task can be interrupted to allow processing of tasks with higher priority in the pond. Furthermore, when an emergency is required, the conventional real-time method,
In other words, after detecting an event when an interrupt occurs and performing exclusive control of the resources that are problematic in interrupt processing, if processing is possible, it is possible to respond in real time by processing the interrupt. Note that when exclusive control is not required, an immediate response can be made as in the real-time method. Additionally, by adding a program loading function and a job scheduling function to this, a multi-job/multi-tasking system can be configured. The effects are (1) Parallel processing can be easily constructed under single task O8. Parallel processing makes the program more efficient. Also, there are times when it is useless without parallel processing. (2) Since normal interrupt processing is managed by the single task O8, program bugs associated with parallel processing are less likely to occur. (3) Since it is in the familiar O5 environment, program development can be improved.

[Explanation of Examples]

An embodiment of the present invention will be described based on the drawings. The explanation will first be given to the data shown in FIGS. 3 and 4, and then to the programs shown in FIGS. 1 and 2. Here, all programs that perform parallel processing are described as tasks. FIG. 3 is a task management table, in which there is a task status 13, a stack pointer 14, and various other data 15 for one task, which are prepared for each task. Here, it is assumed that there are n tasks. The Cheagles are arranged in descending order of priority level. The task status 13 stores the status of whether a task can be executed. '0' means not executable, '1'
' is executable. The stack pointer 14 stores the value of the stack pointer after the register value is stored in the stack when a task is interrupted. The various data 15 include a time count value when a task is interrupted due to a time-up, correspondence data between an input/output event and a task when waiting for input/output completion, and elapsed execution time of the task. FIG. 4 shows a stack, and the number of 0s individually assigned to each task is n, which is the same as the number of tasks. In this figure, the growth direction of the stack is assumed to be upward. The used area 18 is an area that was used by a task immediately before the interruption occurred. The register save area 17 is an area where all registers except the stack pointer of the task are saved when an interruption occurs. Unused area 16 is the remaining unused area of the stack. 1 and 2 are flowcharts of the program. Process 1.2 in FIG. 1 is the part that selects the task to be executed next. Here, task 1 of the task management table
The task status is checked in order from task n to task n, and if the task is executable, the process branches to process 8. If all cannot be executed, the process moves to process 3. Processes 3 to 7 are parts for detecting events by scanning and processing the corresponding events. It is assumed that the number of events is m. For event 1 (1≦1≦m), the event 1 generation process includes a process of making task j (1≦j≦n) executable. Executable means that task status 1 in the task management table of the relevant task is '1'.
It is to do so. The selection of task j can be done explicitly, or it can be indicated indirectly in the interruption process 11. This information is stored in other various data 15. Process 7 is a part that makes a decision to branch to process 1 if the task is executable in the event generation process, and to branch to process 3 if not to perform scanning again. Process 8 is the part where the task is restarted from the interruption point. After restoring the stack pointer value of the task management table of the task to be executed to the stack pointer register, other registers are restored from the stack area starting with the program counter. At this point, task execution resumes. FIG. 2 is a flowchart when the process is interrupted. In process 9, all registers except the stack pointer are saved to the stack area. When restarting, first save the program counter. In process 10, the stack pointer register at this point is saved to the stack pointer 2 of the corresponding task in the task management table. The interruption process in process 11 varies depending on the request from the task.
These include waiting for time, waiting for input/output, and starting other tasks. At this time, when the corresponding task is waiting for an event, the task status 1 of the corresponding task management table is set to 'o'.
Make it. Then, the necessary data is set in the pond various data 3. Thereafter, in process 12, the process shown in FIG. 1 is performed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a flowchart of the selection of executable tasks, the scanning section for detecting events, and the resumption of execution section. FIG. 2 is a flowchart when interrupting. FIG. 3 is a task management table. FIG. 4 shows the configuration of the stack area. "

Claims (1)

[Claims] In a computer device, means for interrupting a program being executed; means for detecting, by scanning, an event that occurs automatically or manually from inside or outside the computer device; and a means for detecting a corresponding program from the detected event. What is claimed is: 1. A program parallel execution device that executes programs in parallel, comprising means for making the program executable, means for selecting a program to be executed next, and means for resuming execution of the interrupted program from the point of interruption.