JPH0795311B2 - Redundant processing device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a duplication processing device, and more particularly to a duplication processing device capable of safely duplicating memory contents.

[Prior Art] Conventionally, in this type of duplex processing device, an online program is executed in an active processing device and a memory,
By updating the memory on both systems, the memory contents are duplicated. The standby system, which is a standby standby device, is configured to execute a test program for failure detection in parallel with the execution of the online program on the ACT side to check the standby standby device for failures and prevent them from occurring. Was there.

[Problems to be Solved] The above-described conventional check has the following problems.

That is, there is a problem that the contents of the online program area, which should be constantly updated from the act side, are destroyed when the standby test program runs away due to a failure or a software bug.

For this reason, there is a problem that even a slight failure destroys the standby memory, and the failure detection function rather deteriorates the system reliability.

The present invention has been made in consideration of the above problems,
The purpose is to provide a duplication processing unit that prevents duplication of the standby memory by updating from the act side and prevents the standby memory from being destroyed due to a failure of the standby test program or runaway of a software bug, and that enables the safe execution of the failure detection function. And

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a duplexing processing device having two processing devices, one of which is an active system, and a memory connected to each processing device. The processor has a means for reading instructions and data from the memory connected to its own system and writing the instructions and data to the memories of its own system and other systems. Write is configured by a waiting means provided between the own system and the other system when the other system memory is empty, and protect means for performing a protect check for a memory write access request from the active system processing device. And a protection means for performing a protection check for memory write access from the standby system independently of the execution of the active system processing unit. And two types of memory write protect means.

[Embodiment] FIG. 1 is a block diagram showing an embodiment of the present invention.

In the figure, 1-1 and 1-2 are processing devices and 2-1 and 2-2, respectively.
Are memories.

3-1 and 3-2 are queues for updating other system memory,
The queue on the standby side updates the memory.

4-1 and 4-2 are bus arbiters, respectively.

5-1 and 5-2 are memory protect means for the memory update request from the act system when the own system is in act and in standby, and 6-1 and 6-2 are memory protect means,
When the local system is in standby, it protects against memory update requests from failure detection programs.

7-1 and 7-2 are failure detection program execution mode flags, which are set when the processor of the own system is on the standby side and a memory write request is made. Further, the reset is performed at the end of the memory write request.

The operation of this device will be described below.

Now, it is assumed that the processing device 1-1 is an active system and the processing device 1-2 is a standby system.

The processing device 1-1 reads an instruction and data from the memory 2-1 and executes a program.

At the time of writing, writing is performed to both the memories 2-1 and 2-2.

When writing to the memory 2-1, the protection means 5-
From 1 to the memory page number determined by the upper 20 bits of the write address 32 bits at that time, the protected memory in the protect means 5-1 is read to check whether or not it is protected. If it is protected, an interrupt occurs as a protect error.
If there is no error, the own memory 2-1 is written.

At the same time, the queue 3-2 is loaded with the address and data at the time of writing. The queue autonomously ejects these pieces of information from the queue, sets the failure detection execution mode flag 7-2 to "0" this time, and checks whether or not it is protected by the protect means 5-2, and if it is writable, uses the arbiter. The communication right with the standby memory 2-2 is acquired and written in the memory 2-2.

At this time, the standby processing device 1-2 has a failure detection program in an area that does not overlap with the online area in the memory 2-2, and the failure detection program is executed independently of the execution of the act processing device 1-1. Run.

When this fault detection program accesses the memory,
The failure detection execution mode flag 7-2 is set to "1" by the processing device.
The protect check of the memory write access at this time is performed by the protect means 6-2.

If the failure detection execution mode flags 7-1 and 7-2 are not provided and the self system is the standby system, the memory access is performed by the protection device, and the memory access is performed by the queue. By means
A method of uniquely determining to perform memory protection is also possible.

[Effects of the Invention] As described above, the present invention has an effect that the standby memory can be duplicated by updating from the act side and the standby failure detection function can be safely executed.

[Brief description of drawings]

 FIG. 1 is a block diagram showing an embodiment of the present invention. 1-1, 1-2: Processing device 2-1, 2-2: Memory 3-1, 3-2: Queue 4-1, 4-2: Bus arbiter 5-1, 5-2: Protecting means 6-1 , 6-2: Protecting means 7-1, 7-2: Failure detection execution mode flag

Claims (1)

[Claims] 1. A duplexing processing device having two processing devices, one of which is an active system, and a memory connected to each processing device, wherein the active system processing device is a memory connected to its own system. It has a means to read and write instructions and data from and to the memory of its own system and other systems, and in this case, writing to the memory of other system is provided between its own system and other system. The queuing means is configured to perform when the other system memory is empty, and the protect means for performing the protect check for the memory write access request from the active system processing device and the execution of the active system processing device are independent. Two types of memory write protect means, that is, a protect means for performing a protect check for a memory write access from a standby system Duplication processing apparatus characterized by having.