JPH03286243A - Resource sharing system - Google Patents

Abstract

PURPOSE:To prevent the set number of a shared resource from being restricted by making the access means of each CPU system access the resource in its own system, and transmitting the executed result of access to an access requesting origin. CONSTITUTION:The CPU system 100 provided with the resource 1005 capable of being accessed by the CPU is connected to each other. The first transmitting means 1001 of each system 100 transmits an access request for the resource 1005 of another system 100 to the same system 100. A first receiving means 1002 receives the executed result of the access from another system obtained as the result of that access request. On the other hand, a second receiving means 1003 receives the access request from another system 100. The access means 1004 accesses the resource 1005 requested by the other side according to the received access request. A second transmitting means 1006 transmits the executed result of this access to the system 100 of the access requesting origin.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a resource sharing system that connects a plurality of systems each having one or more information processing resources and allows each system to share the information processing resources. .

[Prior Art] Conventionally, one CPU system is configured with a central processing unit (CPU) for accessing a memory, a display device, a recording device, and these information processing devices (referred to as resources). 2. Description of the Related Art Information processing systems in which information processing is individually executed by CPU systems are known.

Conventionally, in this type of system, each system is connected to a common bus and mutually exchanges information. Additionally, information processing resources such as memory are connected to a common bus and shared by each system, thereby reducing the number of component devices.

[Problem to be solved by the invention]

However, in conventional systems, when a plurality of commonly used resources are connected via a bus, communication control is required to avoid interference on the common bus, and there is a problem in that there is a limit to the number of connected shared resources.

SUMMARY OF THE INVENTION In view of the above-mentioned points, an object of the present invention is to share resources by making resources included in a system accessible in response to requests from other systems. The goal is to provide a system.

[Means for Solving the Problem] In order to achieve such an object, the present invention
A first transmitting means for transmitting a request for access to the resources of the other CPU system to the U system, and a first receiving means for receiving the execution result of the access from the other CPU system resulting from the access request. and the other CP
a second receiving means for receiving an access request from the U system; an access means for accessing the requested resource in response to the received access request; and a second receiving means for accessing the requested resource in response to the received access request; and a second transmitting means for transmitting to.

[Function] The present invention focuses on the fact that a CPU having a function as an access means can access resources, and allows a CPU of another CPU system to perform access on behalf of the CPU.
By receiving the resource access results of the U system, it becomes possible to access resources in other CPU systems from the own CPU system.

[Example] The description will be given below based on the drawings.

FIG. 1 shows the basic configuration of an embodiment of the present invention.

In FIG. 1, a multiple CPU system 100 having one or more resources 1005 accessible by the CPUs is shown.
The CPUs of each CPU system are interconnected, and the CPUs of each CPU system are
First transmitting means 100 for transmitting a request for access to resources of another CPU system to another CPU system.
1, a first receiving means 1002 that receives the execution result of the access from another CPU system that is received as a result of the access request, a second receiving means 1003 that receives the access request from the other CPU system, and The system includes an access means 1004 that accesses the requested resource in response to a received access request, and a second transmitting means 1006 that transmits the execution result of the access to the other CPU system that is the access request destination.

FIG. 2 shows a specific circuit configuration of an embodiment of the present invention.

In Figure 2, the resource sharing system consists of three CPUs.
(Central processing unit) system and shared memory 1 []
5, each system and the shared memory are commonly connected to a shared bus 104.

The first CPU system 101 consists of a CPU 201.1 or higher resources 202, and a command boat 203.
It is composed of the above resources 302 and command boat 303. Furthermore, the third CPU system 103 includes CPU 4
01, one or more resources 402, and a command boat 403.

Here, each CPU201.301.401 is just a CP
U, but includes memory 110 for storing and executing programs.

In addition, each CPU 201.301.401 has a shared bus 10.
When accessing the command boat of another CPU system or the shared memory 105 via the CPU 4, the CPUs are mutually exclusive controlled by hardware, and the shared bus 1 (14) is not used at the same time.

Each command boat 203, 303, and 403 has a group of registers that stores information sent to its own station, that is, the issuer of the command and the command, and when receiving this information,
Inputs an interrupt signal to the connected CPU.

The operation for resource sharing in such a system configuration will be explained with reference to the flowcharts of FIGS. 3 and 4. FIG. 3 shows a processing procedure for requesting resource access from a destination system and a processing procedure for response processing by the system that receives the access request.

FIG. 4 shows the processing procedure of the system that made the access request and the processing procedure for accessing resources of the system that received the access request.

The CPU of each system when executing this control procedure is the
．． a second transmitting means; a first transmitting means; It operates as a second receiving means.

In this embodiment, a case will be described in which one of the resources 402 of the CPU system 103 is used from the first CPU system 101.

While the first CPU 201 of the first CPU system 101 is executing a user program, when it detects an instruction instructing access to resources of another system (reading/writing information, operation instructions, etc.), Begins execution of a request processing procedure. After writing the message code indicating the requested resource into the shared memory 105, the first CPU 201 writes the message code indicating the requested resource to the command boat 4 of the third CPU system 103.
03, it transmits its own address (issuer information) and a command code indicating a resource use request.

Thereafter, in response to a response from the system of the partner station, the process proceeds to the control procedure shown in FIG. 4 and accesses the resources of the partner station.

On the other hand, in the third C: Ptl system 103, when the command boat 403 receives the resource request command, the third CPU 40 receives the resource request command by an interrupt signal from the command boat 403.
1 interrupts the currently executing processing program and executes the control procedure shown in FIG.

First, the third CPU 401 reads the received command from the command boat 403, and then identifies the received command by code. As a result of the identification, if it is found that the received command is a resource request within the local station, exclusive processing for the requested resource is executed (steps 5701 to 5704 in FIG. 3).

As an example of the occupancy process, a resource occupancy processing program outputs an occupancy request for a resource, and receives an occupancy permission response signal from the resource. After this process, the third CPU4
When 01 confirms the occupancy, it sends a response command indicating that the resource can be occupied to the resource request destination based on the issuer information (step 5705 in FIG. 3).

Thereafter, the command boat 403 is reset, the command reception process is ended, and the suspended execution program is restarted.

The first CPU 201, which receives this response command at the command boat 203 of the first CPU system, executes the control procedure shown in FIG. 4, and executes the access process to the requested resource. For example, if this resource is memory,
Parameter information for using the resource, such as the read address range, is written to the shared memory 105 (step 5611 in FIG. 4). Next, the first CPU
After transmitting a command indicating execution of access to the command boat of the partner station, 201 waits for a response from the partner station indicating completion of access execution (steps 5601 to 5603 in FIG. 3).
.

On the other hand, in the third CPU system that has received the access execution command, the third CPU 401 reads the contents of the command boat in response to an interrupt signal from the command boat 403 and performs code identification. That is, when the third CPU 401 detects that a request for an access execution command has been received, it reads the parameters (in this example, the range of read addresses for the memory) from the shared memory 105 (steps 3711 to 5713 in FIG. 4).

Next, the third CPU 401 accesses the requested resource using an access program (generally called a driver) for the requested resource and read parameters. The access completion result (in this example, information read from the memory) is written to the shared memory 105 (steps 3714 to 5715). Next, a response command indicating the end of the access is sent to the command boat of the access request destination. Thereafter, the third CPLI 401 repeatedly executes the above-mentioned access processing every time there is a request, and ends this procedure in response to an end command from the access request destination (steps 5712-1→5712-2 in FIG. 4).

In the first CPU 201 to which the access request is made, the third C
Upon receiving the access end response command from the PU system 103, the access execution result is read from the shared memory 105.

Upon receiving the necessary execution results, the first CPU 201 sends an end code to the access request destination, waits for the response, and ends this control procedure (steps 5613 to 5 in FIG. 4).
616).

The execution result obtained in this way is
It is used for the arithmetic processing that has been executed up to now.

Note that in this embodiment, each CPU system can request access to the resources of other systems, and in response to access requests from other systems, executes the access on behalf of the system to which the access is requested. Send the execution results to the system that requested access.

As described above, in this embodiment, each CPU system is provided with a communication function with other CPU systems, and accesses resources within the own system requested by other systems through message communication. Therefore, one C
It is not necessary to provide all the resources such as the recording device 1, display device, and storage device in the PU system, and the entire system can be constructed with the minimum necessary resources.

In addition to this embodiment, the following examples are given.

1) Although this embodiment did not explain the case where the resource cannot be occupied immediately, if there is a message response from the resource to the effect that it is currently in operation in response to the time for occupancy, for example, to the access request destination, It is a good idea to respond to a similar message.

In this case, the CP [J system that made the access request will wait for a response indicating that access is possible, and the CPU system that received the access request will send a response to that effect to the access request destination when the resource becomes accessible. do.

2) In this embodiment, the CPU system that receives the access request interrupts the currently executing arithmetic processing and performs the access processing on the requested resource. It is also possible to immediately execute access processing for access requests with a high priority, and to accept access requests after executing the current arithmetic processing for access requests with a low priority.

〔Effect of the invention〕

As described above, according to the present invention, the access means in each CPU system accesses resources within its own system instead of the access means of other CPU systems, and transfers the access execution results to the access request destination. Since the shared resources are transmitted to each other, it is possible to share the resources, and there is no need to connect the resources to a shared bus as in the past, so there is no restriction on the number of shared resources to be installed.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the basic configuration of an embodiment of the present invention, FIG. 2 is a block diagram showing the circuit configuration of an embodiment of the present invention, and FIGS. 3 and 4 show access requests executed by the CPU of the CPU system. 3 is a flowchart illustrating processing procedures for transmission/reception processing and access processing. 100, 101.102.103...CPU system 201.301,401...CPU202, 30
2.402...Resource 203, 303.403...Command boat 104.
...Shared bus, 105...Shared memory, 1001...First transmitting means, 1002...First receiving means, 1003...Second receiving means, 1004...Accessing means, 1005... Resources, 1006... second transmission means.

Claims (1)

[Claims] 1) A plurality of CPU systems having one or more resources accessible by the CPUs are interconnected, and the CPU of each CPU system has the ability to communicate with other CPU systems. The first one that sends a request to access the resource.
a transmitting means; a first receiving means for receiving the execution result of the access from the other CPU system obtained as a result of the access request; a second receiving means for receiving the access request from the other CPU system; an access means that accesses the resource of the request destination in response to the access request; and an access means that accesses the resource of the request destination in response to the access request;
A resource sharing system comprising a second transmitting means for transmitting data to a PU system.