JPS5822459A - Interrupt request monitoring method - Google Patents

Abstract

PURPOSE:To close the interruption mask of an opposite processor in case of the occurrence of a fault in a processor, and to securely prevent the program looping of the processor, by adding an interruption request signal monitoring part to the processor. CONSTITUTION:Processors 1 and 2 constitute a data processing system, and they normally perform processing independently and allows interruption processing between them at need. The processor 2 which receives an interruption request signal from the processor 1 is provided with an interruption request signal monitoring part 4, an interruption request processing program 3, and an interruption control part 5. The interruption request signal is sent through an interruption request signal line and analyzed by the control part 5 and when the interruption mask of the control part 5 is opened, the program 3 is started. In the monitoring part 4, the ceasing of the request signal is stored without reference to the execution of the program 3 to monitor the time difference from monitoring indication from the program 3, and if the processor 1 breaks down to send the request signal continuously, an alarm is sent to the program 3 to close the mask of the control part 5, thus preventing the program looping of interruption processing.

Description

DETAILED DESCRIPTION OF THE INVENTION The gAFi developed by the present invention is an interrupt system suitable for preventing a data processing system configured by an independent processing device from becoming loose due to an inappropriate interrupt caused by an external malfunction. This relates to a request monitoring method.

Interrupt processing in a conventional processing device is controlled only by an interrupt request signal and an interrupt mask, which are external hardware signals. If the interrupt mask is open, the interrupt request signal is accepted immediately, and the processing device interrupts the program that was being executed at that time, starts executing the interrupt request processing program, and sends the interrupt request signal to the interrupt request source. It reports completion and resumes execution of the interrupted program. In this case, if one interrupt request is issued and nine devices are busy, if some failure occurs and the interrupt request signal remains on, the processing device has the disadvantage that it will fall into a loop of interrupt request processing.

An object of the present invention is to eliminate the above-mentioned conventional problems, and to provide means for preventing a program loop in a processing device that processes an interrupt request due to a failure occurring in the device that issued the interrupt request. It is about providing.

A feature of the present invention is that by adding an interrupt request signal monitoring section to the processing device, a failure can occur in the device that has generated the interrupt request.

In some cases, it is possible to detect a state in which the interrupt request signal is not being output even after receiving a report that the interrupt request processing has been completed.

An embodiment of the present invention will be described below with reference to FIG. 1st
The figure is a conceptual diagram when the present invention is implemented in one processing device in a data processing system. Processing devices 1 and 2 are components of a data processing system, and normally perform processing independently of each other. Processing device 1 is processing device 2
Suppose that an interrupt request signal is issued to . The processing device 2 accepts the interrupt the next time the interrupt mask of the interrupt control section is opened, interrupts the friend program being executed at that time, and starts executing the interrupt request processing program.

The interrupt request processing program is tzu interrupt request signal monitoring @4
It issues an @view command to analyze one interrupt cause, executes appropriate processing, and reports the completion of interrupt request processing. The interrupt request signal monitoring unit 4 stores the disappearance of the interrupt request signal regardless of program execution.

After that, the I&S device 2 refers to the interrupt request signal monitoring unit 4 after having the time difference from receiving the interrupt request processing completion report to erasing the interrupt request signal, and interrupts the interrupt request due to a failure in the processing device 1. Check whether the input request signal is released or not. When the interrupt request processing program refers to the interrupt request signal monitoring unit 4 and determines that the interrupt request signal is not being issued due to a failure in the processing device 1, a processing device IK failure occurs to the external alarm device 6. 1) informs the interrupt controller 5 of the above, instructs the interrupt control unit 5 to close the interrupt mask, and returns control to the interrupted program. If it is determined that the interrupt request signal has disappeared normally, one interrupt mask is opened and control is returned to the interrupted program.

If the above control is carried out, even if the interrupt request signal is not issued due to a failure occurring in the processing device 1, a program loop state will occur in which the processing device 2 will execute the interrupt processing program many times. There's nothing wrong. Furthermore, if this method is used, the calculation speed of the processing device 1 is much faster than the calculation speed of the processing device 2, and when the processing device 1 receives the interrupt request processing completion report, it immediately executes another interrupt. Even if an interrupt request signal is generated due to a factor, it is ensured that one interrupt request signal disappears.
I can do ic@iron. If the system simply holds the value of the interrupt request signal, there is no guarantee that the disappearance of the interrupt request signal can be recognized in such a case.

FIG. 2 shows one embodiment of the interrupt request signal monitoring section 40 in FIG. 1. When the interrupt request processing program instructs the interrupt request signal monitoring unit 4 to monitor, the flip-flop 9 is set via the gate 7, and the output terminal Q and warning indicator 1o become high level. The terminal of the flip-flop 9 is a data input and is fixed at a low level in the case of FIG. The T terminal is a trigger input terminal, and when changing from low level to high level, the lip 70 knob 9 reflects the state of the D terminal, that is, the low level, to the output terminal Q. Therefore, when the 1st interrupt request signal disappears after receiving a monitoring instruction, the signal failure characteristic of the interrupt request signal is inverted by the inverter 8 and is applied to the T terminal, and the output terminal Q of the flip-flop 9 becomes low level, and a warning is displayed. Child 1o also becomes low level. still,
Terminal R of flip-flop 9 is an initial reset input. With this configuration, when the interrupt request signal is on, the warning indicator 10 remains at a high level, and it is possible to detect that the operation of the interrupt request source is abnormal.

Figure 3 is a time chart that shows what has been described above. It is assumed that the interrupt mask is normally open. It is assumed that the interrupt control unit 5 suppresses interrupts caused by the same cause while the interrupt request processing program is being executed. When the interrupt request signal is generated, the processing device 2 immediately interrupts the processing program being executed at that time and starts executing the interrupt request processing program. The interrupt request processing program first issues a monitoring instruction to the interrupt request signal monitoring section 4. From this K, interrupt request signal monitoring section 4
The warning indicator 10d becomes high level. Thereafter, the interrupt request processing program issues an interrupt request processing completion report to the processing device IK. At this time, if the interrupt request signal is left as shown in FIG. After notifying the device 6 that an abnormality has occurred in the processing device 7, the processing is interrupted and control is returned to the processing program that was being executed. If the processing device R1 is in the correct state, as shown by the dotted line, the warning indicator goes to 10 low level due to the disappearance of the interrupt request signal, and continues to remain at the low level unless a monitoring instruction is given again by the interrupt request processing program.

If the interrupt request signal is monitored using this method, the processing
Irrespective of the difference in calculation speed between t1 and processor [2], it is possible to reliably prevent a Brograno loop in processor 2 by closing the interrupt mask of processor 2 when a failure occurs in processor W11. It is possible.

[Brief explanation of the drawing]

FIG. 1 shows a second embodiment of the interrupt request signal monitoring system of the present invention.
FIG. 2 is an explanatory diagram of the interrupt request signal monitoring unit in FIG. 1, and FIG.
2 is a timing chart showing a schematic example of the operations shown in FIGS. 1 and 2. FIG. 1... Processing device 1, 2... Processing device 2.3...
Interrupt request processing program, 4... Interrupt request signal monitoring unit, 5... Interrupt control unit, 6... External alarm device.

Claims (1)

[Claims] 1. In a data processing system consisting of several processing devices that can process requests from other devices using interrupt processing, there is a processing device that can be controlled by a program and that By providing an interrupt request signal monitoring unit that does not depend on the calculation execution speed between the two, it is possible to prevent program looseness of the processing device due to failures occurring in the device that issued one interrupt request signal. Interrupt request monitoring method for data processing systems.