JPS6158054A - Run away detection of program - Google Patents

Abstract

PURPOSE:To minimize the run away of a program by setting an address range of a program in a memory part beforehand and detecting the abnormality when a processor accesses over said program range. CONSTITUTION:A processor 1 accesses a program range setting register 2, where first and final addresses in an address range are set at the top position of a program to be executed and stored in a memory 5. A comparator 4 reads the current address through an address bus 7 and compares it with the preset first and final addresses. When the processor 1 accesses over the range of the set addresss with the comparision, and abnormal interrupting signal is transmitted to the processor 1 from the comparator 4.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a program runaway detection method, and in particular,
The present invention relates to a program runaway detection method that can detect program runaway at an early stage using simple hardware in a report processing system using a microprocessor.

[Conventional technology]

In information processing systems that use processors such as microprocessors, the programs being executed may run out of control due to a hardware failure or a mistake in the software such as a program, resulting in pre-planned control not being executed correctly. Something happens.

Conventionally, methods for detecting such program runaways include a parity check method, a method that detects when an instruction is fetched from an address where the program is not stored, and a method that constantly refreshes the program and the interval between refreshes is set for a fixed period of time. A watchdog timer method or the like that detects when the space is empty is generally used or used in combination.

However, even if a program accesses an area outside the area, if it is a data area of memory, the processor will read the contents of that address as a program instruction and execute it, so the program will not actually access the area. By the time a runaway is detected, a considerable amount of time may have passed since the access outside the program area, and there is a risk that data in memory may be destroyed or incorrect output may occur during that time. It becomes a problem.

Further, in such a case, there is a drawback that the evacuation information at that time is often not useful for investigating the cause of the runaway.

[Purpose of the invention]

This invention was made in view of these problems and drawbacks, and it is possible to solve these problems and drawbacks, and to minimize program runaway with N simple hardware. The purpose of the present invention is to provide a program runaway detection method that makes it easy to find the cause of runaway.

[Means to solve problems]

This invention sets the actual memory usage range such as the running range of the program and the data area in a program range setting register for each program, and when the processor accesses outside the set area, the microprocessor or external device etc. to notify the user of an abnormality using means such as an abnormality interrupt,
The idea is to immediately stop a runaway program and, if necessary, take appropriate action in each system at an early stage.

Therefore, the means of the program runaway detection method of the present invention adopted to solve such problems or shortcomings and achieve this purpose is to detect the start address position and the end address of the address range used by a predetermined program to be executed. The program includes a storage section that stores the location, and a determination section that determines whether access has been made beyond the range of addresses stored in the storage section when the program is run.

[Effect]

With this configuration, if the actual memory usage range of each program is set at the beginning of each program, when the processor accesses outside the set range while executing the program,
The abnormality can be immediately notified to the processor or external device by means such as an abnormality interrupt.

As a result, it is possible to minimize runaway programs, make it easier to find the cause of runaways, improve system reliability, and make it easier to find the cause and respond when a system abnormality occurs. becomes.

〔Example〕

Hereinafter, one embodiment of the present invention will be described in detail based on the drawings.

FIG. 1 is a block diagram of main parts of an information processing apparatus to which the present invention is applied.

1 is a processor, and the processor 1 accesses the program range setting register 2 via an address bus 7 and a data bus 8. Then, at the start position of a certain program to be executed stored in the memory 5, the program RF setting register 2 stores the address of the start position and the address of the end position of the address range when the program is executed. set.

When the address range of a certain program is set, the program range setting register 2 controls the control circuit 3 accordingly.
It sends a comparison valid signal 12 to start the control circuit 3, and also sends the set address j11 information to the comparator 4.

Now, when the program is executed, the processor 1 causes the control circuit 3 to fetch an instruction from the memory 5.
A control signal is generated from the processor 1, and a comparison permission signal 9 is sent from the control circuit 3 to the comparator 4.

As a result, the comparator 4 reads the current address from the address bus 7 and compares the current address with the set start address and end address. As a result of this comparison, if the processor 1 accesses an address outside the set address range, the comparator 4 sends an abnormal interrupt signal 10 to the processor 1.

The processor 1 that receives this abnormal interrupt signal 10 performs processing such as saving the values of each register in the abnormal interrupt processing. Then stop execution of the program.

Next, an example of setting the above address range by task processing will be described with reference to FIG.

Now, assuming that the system program is task-managed (managed in units of process processing) by a monitor program, etc., in step 2, the monitor program M clears the program range setting register 2 and stops the comparison valid signal 12. to disable address comparison. Next, in step (2), each task is activated.

In the activated task program, for example, in task A, in step ■a, the program range of the task program is set in the program range setting register 2, the comparison valid signal 12 is generated, address comparison is enabled, and step ■a is executed. At step b, the process corresponding to the corresponding task is executed, and at step 3C, the contents of the program range setting register 2 are cleared, the comparison enable signal 12 is stopped, and address comparison is disabled.

Task B is a predetermined task with similar processing.

Tasks C are started one after another and tasks corresponding to tasks are executed, and when these tasks are completed, the process moves to step ■ of the monitor program M, where the program range of the monitor program M is set in the program range setting register 2, and a comparison is made. The contents of the monitor program M are executed as valid.

Like this, for each task, at the beginning of that task,
By setting the running range of the program, the comparison valid signal 12 shown in FIG. When an abnormality is detected, the task in which the abnormality occurred can be clearly detected.

Also, in the monitor program, by clearing the program range setting register 2 before starting a task and setting the monitor program range when returning to the monitor program after task processing, the entire program in the system can be set. It becomes possible to detect abnormalities.

Here, if the value of the program range setting register 2 can be read when an abnormality occurs, the program range in which the abnormality has occurred can be found based on the set value.

Now, FIG. 3 shows another example of the case where the present invention is applied to a device such as an input/output control device or a communication control device that transfers data between other computers etc. via an interface (or channel). This is an example. Components that are the same as those in FIG. 1 are designated by the same reference numerals.

The control device 15 is a device such as an input/output control device or a communication control device that transfers and exchanges data with other total X113 via an interface (or channel), and the control device 15 and The main difference in configuration from that seen in FIG. 1 is that the ink face (or channel) 6 is connected to an external bus 11 via which
The purpose is to exchange data with the computer 13. Note that 14 is a driver for notifying the computer 13 of an abnormal interrupt signal via the external bus 11.

Here, the processing operation of the control device 15 incorporating the processor 1 is defined by loading a program from the computer 13 to the memory 5.

Then, the computer 13 loads the program into the memory 5, sets the start and end addresses of the loaded program in the program range setting register 2, and gives a start command to the processor 1 to control the execution of the program. do.

Now, in this control device 15, when the program runs out of control and the processor 1 checks an instruction outside the address range set in the program range setting register 2, the comparator 4 sends an abnormal interrupt signal 10. This abnormality interrupt signal 10 notifies the processor 1 of the abnormality, and also
Through the external bus 11, the computer 13 is also connected to the CP [
Raise the J abnormal interrupt signal 16.

On the other hand, the computer 13 that has been notified of the abnormality in the control device 15,
By processing such as reloading the program, the control device 15 is restarted and the corresponding processing is executed again.

As described above, the program range setting register in the embodiment may be any storage unit that stores address information. Further, the comparator, control circuit, etc. may be any determining unit that determines whether an address is within a predetermined range, and are not limited to the embodiments.

〔Effect of the invention〕

According to this invention, the address range of the program is set in advance in the storage unit, and an abnormality is detected when the processor accesses outside the program range, so even if the program is executed and the accessed location is Even if it is above, if it is outside the program range, an abnormality can be detected immediately. As a result, runaway programs can be minimized.

Also, when setting the program range, if you use registers as the writing/L key part, you can freely set the self-program range at the beginning of the program, etc., and you can also respecify the program range settings to be entered for each system. It becomes possible. Furthermore, in the system, eight-run detection can be set for each program currently running, which is more effective in searching for the cause of a runaway.

Therefore, it becomes possible to improve the reliability of the system and to further facilitate the pursuit of the cause and countermeasures when a system abnormality occurs.

[Brief explanation of the drawing]

Figure 1 is a block diagram of the main parts of an information processing device to which the present invention is applied, Figure 2 is a flowchart of processing when setting an address range in task processing, and Figure 3 is a block diagram of the main parts of an information processing device to which the present invention is applied. FIG. 2 is a block diagram of an embodiment when applied to a control device that transfers data between devices. 1--Processor, 2--Program range setting register, 3--Control circuit, 4--Comparator, 5-
・Memory, 6-interface (channel), 7-
・Address bus, 8--data bus, 9--comparison enable signal, 10--abnormal interrupt signal, 11--...
external bus, 12-comparison valid signal, 13-computer;
14-driver, 15-control TFTL device, 1
6-・Paired CPU abnormality interrupt signal. Patent applicant Fuji Electric Manufacturing Co., Ltd. Fuji Facom Control Co., Ltd.

Claims (2)

[Claims] (1) In an information processing system having a processor,
A storage unit that stores the first address position and the final address position of the address range used by a predetermined program to be executed; and when the program is run, access beyond the range of addresses stored in this storage unit is provided. A program runaway detection method, comprising: a determination unit that determines whether or not the program has been executed. (2) The address range to be used is the range of memory in which instruction words are stored, the storage part is a register, and the determination part is
2. The program runaway detection method according to claim 1, wherein the program runaway detection method is performed by comparing addresses at which instructions are fetched.