JPH05342021A - Multitask computer - Google Patents

Abstract

PURPOSE:To shorten interruption response time by executing a specified task, for which high-speed responsiveness is required, parallelly with the other task. CONSTITUTION:The executing task is decided by receiving an interruption request at task deciding means 2-4. When the switching request of the specified task allocated to an auxiliary card 13 is outputted from the task deciding means 2-4 to a task switching part 17, a specified task executing request is outputted to the auxiliary card 13 without stopping the task in execution at this time. The specified task is executed by the auxiliary card 13 receiving the specified task executing request. Thus, the specified task required high-speed responsiveness is executed parallelly with the other task. Therefore, process saving processing or environment preparation processing is reduced from conventional interruption processing, and interruption response time is shortened.

Description

Detailed Description of the Invention

[0001]

The present invention can be used in a control computer that executes various controls in real time,
Regarding improvement of task switching function in multitasking.

[0002]

2. Description of the Related Art Generally, conventional control computers are equipped with various programs for executing predetermined tasks corresponding to various processes to be controlled. Then, a plurality of tasks are switched by generating an interrupt request from the outside or the inside.

On the other hand, recently, there is a general-purpose OS such as UNIX for managing the execution (multitasking) of a plurality of programs, and this general-purpose OS should be installed in a control computer in consideration of software development efficiency. Has become. FIG. 4 shows functional blocks relating to interrupt processing of a control computer equipped with a general-purpose OS.

In this control computer, an interrupt request is accepted by an interrupt accepting section 2 of a general-purpose OS (hereinafter referred to as "kernel section") 1. When an interrupt request is input to the interrupt receiving unit 2, the control computer is set to the interrupt disabled state in order to prevent other interrupts from being input in a multiple manner during the processing in the kernel unit 1. On the other hand, the interrupt factor determination unit 3 determines the process (execution process) corresponding to the interrupt request by referring to the interrupt factor table 4 (the interrupt request and the processing process corresponding thereto are described as a pair). ..

Then, the task switching unit 5 switches to the execution process determined by the interrupt factor determination unit 3. For example, when an execution request for the process B is issued while the process A is being executed, the process A being executed is stopped, and data such as registers is saved in the save unit 6 in preparation for restart. Next, the execution environment of process B is prepared. Specifically, the resource is allocated to the process B. Alternatively, the process B is loaded from the auxiliary storage device into the main storage device. After preparing such an execution environment, the process B is executed.

The control computer, as shown in FIG.
If an interrupt request is input at time t1 during execution of process A, interrupt request determination processing (t1 to t2) and process A
Of the process B from the time t4 after the evacuation process (t2 to t3) and the environment maintenance process (t3 to t4) of the process B.
Is started. Therefore, in the control computer, the time until the work of the process B is started, that is, the interrupt response time becomes long, and there is a possibility that the high-speed response required by the computer for real-time control cannot be realized.

[0007]

As described above, the computer provided with the conventional multitasking function has a long interrupt response time until the task for which an interrupt request is issued is executed.
Therefore, it has been desired to shorten the interrupt response time.

The present invention has been made in view of the above circumstances, and it is possible to execute a specific task requiring high-speed responsiveness in parallel with other tasks, thereby shortening the interrupt response time. It is an object of the present invention to provide a multitasking computer that can achieve this.

[0009]

In order to achieve the above object, a multitasking computer of the present invention assigns an execution task to a task deciding means for accepting an interrupt request and deciding an execution task and a task decided by this task deciding means. A main control unit having a task switching unit for switching, and an auxiliary card connected to the main control unit via a predetermined data transmission path for executing a specific task are provided, and the task determining unit is connected to the task switching unit. If a request to switch the specific task assigned to the auxiliary card is issued, the task switching means issues a specific task execution request to the auxiliary card without switching the task currently being executed, The auxiliary card receives the specific task execution request and executes the specific task.

[0010]

In the multitask computer of the present invention, the interrupt request is accepted by the task determining means and the execution task is determined. When the task determining means issues a request for switching the specific task assigned to the auxiliary card to the task switching means, the specific task execution request is issued to the auxiliary card without stopping the task being executed at that time. Is issued. The specific task is executed by the auxiliary card that has received the specific task execution request. Therefore, the process saving process and the environment preparation process are reduced from the conventional interrupt process, and the interrupt response time is shortened.

[0011]

EXAMPLES Examples of the present invention will be described below. FIG. 1 shows a schematic system configuration of a control computer according to an embodiment of the present invention.

The control computer of this embodiment is a CPU 1 that operates under the control of a general-purpose OS and executes several types of task processing.
0 is connected to the interrupt signal input mechanism 12 and the auxiliary card 13 via the bus 11 serving as a data transmission path.

The CPU 10 executes a program for executing the process A previously stored in the main storage device 14 at a timing managed by a general-purpose OS installed in the system. In the figure, the CPU
Although only the process A is shown as the process to be executed by the CPU 10, the CPU 10 actually performs the multitasking process while switching a plurality of processes.

The auxiliary card 13 executes a process B as a specific task according to an instruction from the CPU 10
It comprises a PU 15 and a main memory 16 in which a program for executing the process B is stored. In this auxiliary card 13, the execution environment of the process B is set by the CPU 10 at the time of initialization.

FIG. 2 shows functional blocks of a kernel unit 10 'as a main control unit in the CPU 10. The kernel unit 10 ′ receives an interrupt request input from the interrupt signal input mechanism 12 via the bus 11 by the interrupt receiving unit 2
Receive at. The interrupt receiving unit 2 puts the control computer in the interrupt disabled state only during the interrupt processing. The interrupt request accepted by the interrupt acceptance unit 2 is input to the interrupt factor determination unit 3. The interrupt factor determination unit 3 is
By referring to the interrupt factor table 4, the process corresponding to the interrupt request is determined as the execution process. The interrupt acceptance unit 2, the interrupt factor determination unit 3, and the interrupt factor table 4 constitute a task determination unit. Information about the execution process determined by referring to the interrupt factor table 4 is given to the task switching unit 17.

The task switching unit 17 has a function of determining whether or not the determined execution process is the process B executed by the auxiliary card 13, and a task specific to the auxiliary card 13 when the execution process is the process B. It has a function of outputting an execution request and a function of performing the same switching process as the above-described conventional one when the execution process is other than the process B. Next, the operation of this embodiment configured as described above will be described. It is assumed that an interrupt request for execution of the process B is input from the interrupt signal input mechanism 12 at time t1 in FIG. 3 while the CPU 10 is executing the process A.

When an interrupt request is input, the interrupt acceptance unit 2
Sets the control computer to the interrupt disabled state. On the other hand, the interrupt factor determination unit 3 refers to the interrupt factor table 4 and
The process requested for interruption is specified, and the determined process information is output to the task switching unit 17.

The task switching unit 17 outputs a specific task execution request to the auxiliary card 13 because the decision process input from the interrupt factor determination unit 3 is the process B. The process A being executed at this time continues to be executed.

In the auxiliary card 13 to which the specific task execution request output from the task switching unit 17 is input via the bus 11, the execution environment of the process B is prepared in advance, so that the execution of the process B is immediately started. To be done.

As described above, according to this embodiment, since the execution of the specific process B is executed by the auxiliary card 13 and the execution of the process A by the CPU 10 can be executed in parallel, the specific process B is interrupted. The process B can be executed immediately after the request determination is completed. Therefore, since it is not necessary to stop and save the process A, the task switching process can be simplified, and the time required for the process A save process and the process B environment maintenance process can be deleted, and the interrupt request response time can be shortened. it can. It should be noted that the present invention is not limited to the above-described embodiment, and can be modified and implemented without departing from the scope of the present invention.

[0021]

As described in detail above, according to the present invention, it is possible to execute a specific task requiring high-speed responsiveness in parallel with other tasks, thereby shortening the interrupt response time. A multitasking computer can be provided.

[Brief description of drawings]

FIG. 1 is a system configuration diagram of a control computer according to an embodiment of the present invention.

FIG. 2 is a functional block diagram of a CPU included in a control computer according to an embodiment.

FIG. 3 is a diagram for explaining an interrupt processing operation in the control computer according to the embodiment.

FIG. 4 is a functional block diagram of a CPU provided in a conventional control computer.

5 is a diagram for explaining an interrupt processing operation in the control computer shown in FIG.

[Explanation of symbols]

2 ... Interrupt acceptance unit, 3 ... Interrupt factor determination unit, 4 ... Interrupt factor table, 10, 15 ... CPU, 10 '... Kernel unit, 11 ... Bus, 12 ... Interrupt signal input mechanism, 13 ... Auxiliary card, 14, 16 ... main storage device, 17 ... task switching unit.

Claims (1)

[Claims] 1. In a multitasking computer that executes multitasking in response to an interrupt request under the control of a general-purpose operating system, a task determining unit that accepts an interrupt request and determines an execution task, and the task determining unit determines the task. A main control unit having a task switching unit for switching an execution task to a task; and an auxiliary card connected to the main control unit via a predetermined data transmission line to execute a specific task, When a switching request for the specific task assigned to the auxiliary card is issued to the switching means, the task switching means executes the specific task on the auxiliary card without switching the task being executed at that time. A request is issued, and the auxiliary card executes the specific task upon receiving the specific task execution request. Multitasking computer, wherein the door.