JPH09265406A - Exclusive control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new exclusive control system for executing highly reliable exclusive control by multiplexing exclusive mechanisms by providing them for plural and providing an exclusive control mechanism for controlling the exclusive mechanisms. SOLUTION: When an execution body 2 issues an exclusive acquisition request, an acquisition execution means 11 executes exclusive acquisition to be supplied to the execution body 2 to the exclusive mechanisms 3 corresponding to an order managed by an order management means 10. An informing means 12 informs the execution body 2 of an exclusive acquisition request origin of the exclusive acquisition when the acquisition execution means 11 succeeds in the exclusive acquisition to all the operatable exclusive mechanisms 3. On the other hand, when the execution body 2 issues the release request of the exclusive acquisition, a release execution means 13 executes the release of the exclusive acquisition supplied to the execution body 2 to the exclusive mechanisms 3 corresponding to the order managed by the order management means 10. When a fault is generated in the exclusive mechanism and it is inoperable, the exclusive control mechanism 4 skips the exclusive acquisition of the exclusive mechanism 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exclusive control method for executing exclusive control of resources, and more particularly to an exclusive control method for executing highly reliable exclusive control.

In a computer system in which a plurality of execution bodies run in parallel, the execution bodies execute data processing while exclusively acquiring resources. In order to improve the reliability of computer systems, it is necessary to build exclusive control technology for highly reliable resources.

[0003]

2. Description of the Related Art In a conventional computer system, an exclusive mechanism for controlling exclusive acquisition is prepared, and an exclusive acquisition request for a resource issued by an executable is used to control an exclusive execution request to execute parallel executions. It was adopted to permit the use of resources to.

More specifically, an execution unit writes an identification data of another execution unit in a single memory area by using an exclusive instruction such as a compare swap instruction. On the condition that it does not exist, the identification data is written, and the exclusive acquisition is controlled by checking whether or not the writing is successful.

[0005]

However, according to such a conventional technique, when a failure occurs in the exclusion mechanism, control of exclusion acquisition becomes impossible and the entire system must be stopped. was there.

That is, since there is only one exclusion mechanism, there is a problem that if a failure occurs in that exclusion mechanism, control of exclusion acquisition becomes impossible and the entire system must be stopped. is there.

A computer system may have a dual structure in order to improve reliability. In this case, there are two memory areas to which exclusive instructions are written. However, even in this case, the number of exclusive instructions to be issued is one, and since the identification data is written to two memory areas at the same time by the exclusive instruction, the exclusion mechanism is substantially 1
Only one is prepared. From now on, if a failure occurs in the exclusion mechanism, the problem that the acquisition of exclusion cannot be controlled will remain unsolved.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a new exclusive control system for executing highly reliable exclusive control.

[0009]

FIG. 1 shows the principle configuration of the present invention. In the figure, reference numeral 1 is a computer system equipped with the present invention, in which a plurality of execution bodies 2 executing in parallel is an exclusion mechanism 3.
Is used to exclusively acquire resources and execute data processing.

The computer system 1 of the present invention comprises an exclusive mechanism 3.
A plurality of (1) to (3) are provided for multiplexing, and an exclusive control mechanism (4) for controlling the exclusive mechanism (3) is provided. The exclusive control mechanism 4 includes an order management means 10 and an acquisition execution means 11
, Notifying means 12, release executing means 13, and specifying means 1
4 and allocation means 15.

The order management means 10 manages the order assigned to the exclusion mechanism 3. The acquisition execution means 11 executes the exclusion acquisition given to the execution body 2 for the exclusion mechanism 3, when the execution body 2 issues the exclusion acquisition request. The notifying means 12 notifies the execution body of the exclusion acquisition request issuing source of the exclusion acquisition.

The release executing means 13 executes release of the exclusive acquisition given to the executing body 2 to the exclusion mechanism 3 when the executing body 2 issues the exclusive acquisition releasing request. When the executor 2 issues a request to specify an exclusive acquirer, the identifying unit 14 identifies the executor 2 that has acquired the exclusive acquisition and notifies the executor 2 of the specific request issuing source. The allocating means 15 allocates a prescribed order to the exclusion mechanism 3 when the exclusion mechanism 3 is added.

The acquisition executing means 11 gives the exclusion acquisition to any one of the execution bodies 2 when the exclusion mechanism 3 gives the execution body 2 other than the execution body 2 which issued the exclusion acquisition request. When there is no exclusive mechanism 3, the exclusive acquisition given to the other executing body 2 may be executed for the exclusive mechanism 3.

In the computer system 1 of the present invention configured as above, when the execution body 2 issues an exclusive acquisition request, the acquisition execution means 11 follows the order managed by the order management means 10 and instructs the exclusion mechanism 3 to do so. Then, the exclusive acquisition given to the executing body 2 is executed, and in response to this processing, the notification means 12
When the acquisition executing means 11 succeeds in acquiring the exclusion for all the exclusivity mechanisms 3 which are operable, the acquisition execution means 11 notifies the execution body 2 of the exclusion acquisition request issuing source of the exclusion acquisition.

On the other hand, when the execution body 2 issues a release request for acquisition of exclusion, the release execution means 13 gives the exclusion mechanism 3 the exclusion body 3 to the execution body 2 in accordance with the order managed by the order management means 10. Perform release of acquisition. When the execution body 2 issues a request to specify the exclusive acquisition person, the specifying unit 1
4 refers to the exclusion mechanism 3 in the order opposite to the order managed by the order management means 10 to specify the execution body 2 to which the exclusion acquisition is given first, and issue the specification request. Notify the original executing body 2.

In this way, the computer system 1 of the present invention has a configuration in which, as shown in FIG. 2, the exclusion mechanisms 3 are multiplexed by preparing three exclusion mechanisms 3 such as ','. The executor 2 activates the exclusive control mechanism 4 so that, for example, as shown in FIG.
The exclusive mechanism 3 is exclusively acquired in the order of "", and the exclusive structure is acquired when all the exclusive mechanisms 3 can be exclusively acquired. At this time, the exclusion control mechanism 4 skips the acquisition of the exclusion mechanism 3 when the exclusion mechanism 3 is not implemented or when the exclusion mechanism 3 cannot operate due to a failure. I will go.

Then, the executor 2 activates the exclusive control mechanism 4 so that "→ '→" as shown in FIG.
The configuration is such that the exclusion acquisition of the exclusion mechanism 3 is released according to the order of ″ ″, and the exclusion is released when the exclusion acquisition of all the exclusion mechanisms 3 can be released.

Then, as shown in FIG. 4B, ""
The configuration is such that the execution body 2 that has acquired the exclusion mechanism 3 in an exclusive manner is detected in the order of → '→', and the execution body 2 that is detected first is identified as the execution body 2 that has the exclusion acquisition. Collect it.

When this configuration is adopted, the exclusion mechanism 3
Is added, the allocating means 15 allocates, for example, the last order to the exclusion mechanism 3, and the order managing means 10
Register with. At the time of this addition, it happens that any of the executing bodies 2 already has exclusive acquisition. In consideration of this, the acquisition execution means 11 determines that which execution body 2 the exclusion mechanism 3 gives the exclusion acquisition to the execution body 2 different from the execution body 2 that issued the exclusion acquisition request. Also, if there is an exclusion mechanism 3 that has not given exclusion acquisition, that exclusion mechanism 3
Is determined to have been added, the exclusive acquisition given to the other executing body 2 is executed for the exclusive mechanism 3.

Thus, according to the present invention, the exclusion mechanism 3
Even if a failure occurs in a part of the above, it becomes possible to continue the control logic of the exclusion acquisition as it is when no failure occurs, so that highly reliable exclusive control can be realized.
Even when the exclusion mechanism 3 is added, the control logic for acquisition of exclusion can be continued as it was before the addition, so that highly reliable exclusion control can be realized.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail according to embodiments. In the embodiment described below, as shown in FIG. 5, A execution body 2a, B execution body 2b, C execution body 2
It is assumed that there are three execution bodies 2 called c and that two exclusion mechanisms 3 shown by and an exclusion mechanism 3-2 are prepared. Here, the exclusion mechanisms 3-1 and 2 are implemented by modules, so that, for example, initially, only the exclusion mechanism 3-1 operates, and then the exclusion mechanism 3-2 is added.

These exclusion mechanisms 3-1, 2 are specifically composed of control registers in which an initial value "0" is set, and the A execution unit 2a, the B execution unit 2b, and the C execution unit 2c. Ensures the first executor ID that is accessible to and written by them. Then, if the same value as the execution body ID is written when the execution body ID is written, another control register that performs initialization processing is prepared.

Although not shown in FIG. 5, an exclusive control mechanism 4 is prepared as shown in FIG. 1, and when the exclusive control mechanism 4 is activated from the execution bodies 2a, b, c, exclusion is performed. Perform control processing.

6 to 8 show an embodiment of a processing flow executed by the exclusive control mechanism 4. Next, the present invention will be described in detail according to these processing flows. When the exclusive body acquisition request is issued from the execution bodies 2a, b, c, the exclusive control mechanism 4 first, as shown in the processing flow of FIG. Then, the execution unit IDs of the execution units 2a, b, and c (hereinafter, sometimes referred to as self-execution units) of the exclusion acquisition request source are written, and in the subsequent step 2, whether or not this access is successful is determined. to decide.

In this step 2, the exclusion mechanism 3-1 indicated by
When determining that access to is not successful,
That is, when it is determined that the exclusion mechanism 3-1 indicated by has a failure or the exclusion mechanism 3-1 is not installed, the process proceeds to step 3 and the own execution body is set to the "X execution body". Set.

On the other hand, in step 2, the exclusion mechanism 3 indicated by
When it is determined that the access to -1 has succeeded, the process proceeds to step 4, and it is determined whether the exclusion mechanism 3-1 indicated by can be acquired exclusively (may be already acquired as described later). ), If it is determined that the exclusive acquisition has been completed or the exclusive acquisition has already been completed, the process proceeds to step 5 and the self-execution body is set in the "X execution body". That is,
When the execution body ID of the self-execution body has been written to the exclusion mechanism 3-1 and the execution body ID has already been written, the self-execution body is set to the “X execution body”.

On the other hand, in step 4, the exclusion mechanism 3 indicated by
When it is determined that -1 cannot be acquired exclusively and has not been acquired, that is, an execution body 2 other than the self-execution body
When it is determined that a, b, and c have exclusively acquired the exclusion mechanism 3-1, the process proceeds to step 6, and the execution body that has exclusively acquired the exclusion mechanism 3-1 in the "X execution body". Set 2a, b, c.

When "X execution body" is set in step 3 / step 5 / step 6, then in step 7,
The execution unit ID of the "X execution unit" is written to the exclusion mechanism 3-2 indicated by ', and it is determined in subsequent Step 8 whether or not this access has succeeded.

In this step 8, the exclusion mechanism 3 indicated by '
When it is determined that the access to -2 is successful, the process proceeds to step 9, and it is determined whether the exclusion mechanism 3-2 indicated by'has been exclusively acquired or has already been acquired. When it is determined that the exclusive acquisition has been completed or the exclusive acquisition has been completed, the process proceeds to step 10 and the "X executive" has the exclusive acquisition right.

On the other hand, in step 9, when it is judged that the exclusion mechanism 3-2 indicated by 'cannot be exclusively acquired, and is not already acquired, that is, the execution body 2a different from the "X execution body", When it is determined that b and c have exclusively acquired the exclusion mechanism 3-2, the execution body 2 that has acquired the exclusion
It is assumed that a, b, and c have exclusive acquisition rights.

On the other hand, when it is judged in step 8 that the access to the exclusion mechanism 3-2 indicated by "" is not successful, that is, whether the exclusion mechanism 3-2 indicated by "" has a failure, When it is determined that the exclusion mechanism 3-2 is not implemented, the process proceeds to step 11, and it is determined whether or not the access to the two exclusion mechanisms 3-1, 2 has failed, and both have failed. If it is determined that the exclusive acquisition processing is impossible, if it is determined that the exclusive acquisition processing is not possible, the process proceeds to step 10 and the "X executive" has the exclusive acquisition right.

In this way, when the exclusive body acquisition request is issued from the executing bodies 2a, b, c, the exclusive control mechanism 4 follows the processing flow of FIG. 6 and follows the order of "→ '" in the exclusive mechanism 3-1. , 2 are exclusively acquired, and two exclusion mechanisms 3
-1,2 is successfully acquired, or when one of them is inoperable and the other exclusion mechanism 3-1,2 that is operational is successfully acquired Exclusive execution is notified to the execution bodies 2a, 2b, and 2c that are acquisition request issuing sources.

That is, according to the processing of the exclusion control mechanism 4, for example, when the A execution body 2a issues an exclusion acquisition request, the A execution body 2a and the exclusion mechanism 3-1 shown by
When the execution body ID can be written into both of the exclusion mechanism 3-2 shown in (1), the A execution body 2a has the exclusive acquisition right.

When the A-executable body 2a issues the exclusion acquisition request, the A-executable body 2a writes the execution body ID into the exclusion mechanism 3-1 indicated by, but the exclusion mechanism 3 indicated by '.
-2 cannot be written, the execution unit ID is written in the exclusion mechanism 3-2 indicated by ', for example, B execution unit 2b.
Will have the exclusive acquisition right.

This is because the A execution body 2a issues an exclusion acquisition request while the B execution body 2b is releasing the exclusion acquisition right,
This occurs when the exclusion mechanism 3-1 shown by is added after the acquisition of the exclusive acquisition right of the B execution body 2b.

When the A-executable body 2a issues an exclusion acquisition request, for example, the exclusion mechanism 3 indicated by the B-executable body 2b.
When the execution body ID is written in -1, the execution body ID of the B execution body 2b is written in the exclusion mechanism 3-2 indicated by ', so that the A execution body 2a determines the exclusion mechanism 3-2.
The execution body ID of the B execution body 2b is written on behalf of.

This substitute process is executed by the exclusion mechanism 3-2 indicated by "."
Occurs when the B execution unit 2b is added after the acquisition of the exclusive acquisition right. According to this proxy processing, the above-mentioned exclusion acquisition has occurred. At this time, B
The executing body 2b has the exclusive acquisition right.

Further, when the A execution body 2a issues the exclusion acquisition request, if the exclusion mechanism 3-1 indicated by is in failure or the exclusion mechanism 3-1 is not installed,
The A execution body 2a sends an execution body ID to the exclusion mechanism 3-2 indicated by '.
Is written and the A execution body 2a has the exclusive acquisition right. If you can't write, '
For example, the B execution body 2b that has written the execution body ID in the exclusion mechanism 3-2 has the exclusive acquisition right. At this time, there is a failure in the exclusion mechanism 3-2 shown in ',
If the exclusion mechanism 3-2 is not implemented, exclusion cannot be acquired.

On the other hand, the exclusive control mechanism 4 includes the execution bodies 2a, 2b, 2c.
When an exclusive acquisition release request is issued from, as shown in the processing flow of FIG. 7, first, in step 1, a zero value, which is an initial value, is written to the exclusion mechanism 3-1 indicated by. Execute, and in the following step 2, exclusion mechanism 3 indicated by '
For -2, perform initialization so that the initial value, zero value, is set.

Then, in step 3, it is judged whether or not the access to the exclusion mechanism 3-2 indicated by 'has succeeded, and when it is judged that the access has succeeded, the process proceeds to step 4 to acquire the exclusion. It is assumed that the execution requesting execution bodies 2a, 2b, and 2c (self-execution bodies) have released the exclusive acquisition.

On the other hand, when it is judged in step 3 that the access to the exclusion mechanism 3-2 indicated by 'is unsuccessful, that is, whether the exclusion mechanism 3-2 indicated by' has a failure or not, When it is determined that the exclusion mechanism 3-2 is not implemented, the process proceeds to step 5, and it is determined whether or not the access to the two exclusion mechanisms 3-1, 2 has failed, and both have failed. When determining that, it is determined that the exclusive acquisition release processing is impossible.

In this manner, when the execution bodies 2a, b, and c issue the exclusion acquisition release request, the exclusion control mechanism 4 follows the processing flow of FIG. When releasing the exclusive acquisition of -1,2 and succeeding in releasing the exclusive acquisition, the exclusive body is notified to the execution bodies 2a, b, and c of the issuer of the request to release the exclusive acquisition. It goes.

On the other hand, the exclusive control mechanism 4 includes the execution bodies 2a, b, c.
When a request for specifying an exclusive acquirer is issued by the user, as shown in the processing flow of FIG.
The execution unit ID written in the exclusion mechanism 3-2 is referred to, and in the subsequent step 2, it is determined whether or not this access is successful.

In this step 2, the exclusion mechanism 3 indicated by '
-When deciding that the access to -2 is not successful, that is, when deciding that the exclusion mechanism 3-2 indicated by 'has a failure or that exclusion mechanism 3-2 is not implemented , Go to step 3, refer to the execution unit ID written in the exclusion mechanism 3-1 indicated by, and in the following step 2, determine whether or not this access was successful, and determine that it is not successful. At this time, that is, when it is determined that the exclusion mechanism 3-1 has a failure or the exclusion mechanism 3-1 is not implemented, it is determined that the exclusion acquirer cannot be specified.

On the other hand, when it is judged in step 2 that the access to the exclusion mechanism 3-2 indicated by 'is successful, and in step 4, the access to the exclusion mechanism 3-1 indicated by is successful. Step 5
If it is determined that the execution unit ID has not been written in the exclusion mechanism 3-1, 2 that has been successfully accessed, and if it has not been written, the process proceeds to Step 6 to obtain the exclusion. After determining that there is no person who has acquired the exclusion request and ending the process of specifying the exclusion acquirer, in step 7, the exclusive acquisition request is received from the execution units 2a, b, c that have issued the exclusion request specifying request. Exclusive acquisition processing is performed according to the processing flow of FIG. 6 described above.

On the other hand, in step 5, when it is judged that the execution unit ID is written in the exclusion mechanism 3-1, 2 that has been successfully accessed, that is, the execution unit 2 having the exclusive acquisition right.
When it is determined that a, b, and c are present, the process proceeds to step 8, and the monitoring mechanism (not shown) is called to enter the monitoring process of the execution bodies 2a, b, and c having the exclusive acquisition right, and the following step 9 is performed.
Then, by the monitoring process of the monitoring mechanism, it is determined whether or not the executing bodies 2a, 2b, 2c having the exclusive acquisition right are operating, and when it is determined that they are operating, the process proceeds to step 10. After the exclusion acquirer identification process is completed, the process periodically returns to step 1 to continue the exclusion acquisition person identification process.

On the other hand, when it is judged in step 9 that the executing bodies 2a, 2b, 2c having the exclusive acquisition right are not operating,
Proceeding to step 11, the exclusive acquisition release processing is performed according to the processing flow of FIG. 7 described above, and then step 1
Execution unit 2 that has issued the specific request for the exclusive acquirer
The exclusive acquisition requests from a, b, and c are received, and the exclusive acquisition processing is performed according to the processing flow of FIG. 6 described above.

In this way, the exclusive control mechanism 4 issues a request for specifying the exclusive acquirer from the execution units 2a, 2b, 2c,
According to the process flow of FIG. 8, the execution body 2a which has exclusively acquired the exclusion mechanisms 3-1, 2 in the order of "'→"
Detecting b, c, the first detected execution body 2a, b, c
Is specified as having the exclusive acquisition right, and the exclusive acquisition right of the specified execution body 2a, b, c is released to the execution body 2a, b, c of the specific request issuer. Meet up.

As described above, in the computer system 1 of the present invention, the executing body 2 acquires the exclusion mechanism 3 in an exclusive manner, for example, in the order of "→ '→""and excludes all exclusion mechanisms 3. When it can be acquired, it takes a structure to acquire exclusive. The exclusive acquisition of the exclusion mechanism 3 is released in the order of "→ '→''", and the exclusive release is released when the exclusion acquisition of all the exclusion mechanisms 3 can be released. Then, the execution body 2 which has exclusively acquired the exclusion mechanism 3 is detected according to the order of “″ → ′ →”, and the execution body 2 which is detected first is the execution body 2 which has the exclusive acquisition. The configuration that specifies

According to this configuration, when the exclusive mechanism 3 is added, if the prescribed order is assigned to the additional exclusive mechanism 3, no trouble occurs. As shown in FIG. 9, while the execution body 2 is executing the exclusion acquisition, even if the exclusion mechanism 3 is added to the beginning or the end,
No trouble will occur.

Further, as shown in FIG.
Even if the exclusion mechanism 3 is added at the end, for example, after the owner has the exclusive acquisition right, as described in the processing flow of FIG. Since the execution body 2 having the exclusive acquisition right is registered in the exclusion mechanism 3, no trouble occurs.

[0052]

As described above, in the present invention, since the exclusive mechanism is multiplexed, even if a part of the exclusive mechanism fails, the exclusive control logic does not fail. Since it becomes possible to continue the same as when there is no time, highly reliable exclusive control can be realized. Then, even when the exclusion mechanism is added, the control logic for acquisition of exclusion can be continued as it was before the addition, so that highly reliable exclusion control can be realized.

[Brief description of drawings]

FIG. 1 is a principle configuration diagram of the present invention.

FIG. 2 is a configuration example of an exclusive mechanism.

FIG. 3 is an explanatory diagram of processing of the present invention.

FIG. 4 is an explanatory diagram of a process according to the present invention.

FIG. 5 is a configuration diagram of an exclusion mechanism assumed in the embodiment.

FIG. 6 is an example of a processing flow executed by an exclusive control mechanism.

FIG. 7 is an example of a processing flow executed by an exclusive control mechanism.

FIG. 8 is an example of a processing flow executed by an exclusive control mechanism.

FIG. 9 is an explanatory diagram of a process according to the present invention.

FIG. 10 is an explanatory diagram of a process according to the present invention.

[Explanation of symbols]

 1 Computer System 2 Executor 3 Exclusive Mechanism 4 Exclusive Control Mechanism 10 Order Management Means 11 Acquisition Execution Means 12 Notification Means 13 Release Execution Means 14 Identification Means 15 Allocation Means

Claims (5)

[Claims] 1. In a computer system in which a plurality of execution bodies executing in parallel execute data processing while exclusively acquiring resources by using an exclusion mechanism, the exclusion mechanisms are multiplexed and the exclusion mechanisms have a predetermined order in advance. When the execution body issues an exclusion acquisition request, the acquisition execution means for executing the exclusion acquisition given to the execution body for the exclusion mechanism according to the above order and the acquisition execution means are adopted. An exclusion control method characterized by comprising notifying means for notifying the execution body of the exclusion acquisition request issuing source of the exclusion acquisition when the exclusion acquisition is successful for all operable exclusion mechanisms. 2. The exclusive control method according to claim 1, wherein when the execution unit issues a release request for exclusive acquisition, the execution unit is given to the execution unit in the same order as the acquisition execution unit. An exclusive control method characterized by comprising release execution means for executing release of exclusive lock acquisition. 3. The exclusive control system according to claim 1 or 2, wherein when the execution body issues a specific request of the exclusion acquirer, the exclusion mechanism is referred to in the reverse order of the acquisition execution means. The exclusive control method is characterized by including a specifying unit that first specifies an execution unit to which exclusive acquisition is given and notifies the execution unit of the specific request issuer of it. 4. The exclusion control method according to claim 1, 2 or 3, further comprising: allocation means for allocating a prescribed order to the exclusion mechanism when the exclusion mechanism is added. control method. 5. The exclusive control system according to claim 4, wherein the acquisition execution means is configured to determine which execution body when the exclusion mechanism gives an exclusive acquisition to an execution body other than the execution body that issued the exclusion acquisition request. If there is also an exclusion mechanism that does not give an exclusion acquisition, an exclusion control method characterized by executing the exclusion acquisition given to the other executing body for the exclusion mechanism.