JPS62197818A - Data transfer control system - Google Patents

Abstract

PURPOSE:To attain a data transfer control system that can perform the flexible and effective fault processing and retrial processing, by inhibiting the indication for the next execution at an instruction control part until the end of the transfer of data under execution and the presence or absence of the abnormality produced in a data transfer mode are confirmed in case the contents of a synchronous indication field show a synchronous indication instruction. CONSTITUTION:When a data transfer instruction is confirmed through a fact that an instruction control part 30 decodes an instruction code, an indication for execution is given to a transfer control part 40 by the execution request signal RQ. At the same time, an action code, the addresses to memory devices (1)10 and (2)20, and a synchronous indication instruction SYC for transfer of data are transmitted by a request code signal RQC, an address signal AD and a synchronous indication field SYC' respectively. An interruption report signal INT functions to give a report to the part 30 when the part 40 receives a report on detection of an abnormal state from both memory devices or the part 40 itself detects an abnormal state. The part 30 inhibits the indication for the next instruction by the signal INT and starts an interruption processing sequence.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a data transfer control method in a data processing system, and particularly to control over overlap of data transfer instruction execution sequences between two storage areas.

〔overview〕

The present invention provides a data transfer control method for controlling data transfer between two different storage areas in a data processing system, in which a synchronization instruction field for instructing data transfer synchronization is set in a command word, and an instruction control unit In accordance with the result of decoding the command word, a data transfer execution instruction and the contents of the synchronization instruction field are sent to the data transfer control unit, and if the contents of the synchronization instruction field are a synchronization instruction,
By suppressing the next execution instruction in the instruction control unit until the data being executed is transferred and the presence or absence of an abnormal event that occurred during data transfer is confirmed, flexible and efficient failure handling and This enables retry processing and improves system reliability and throughput.

[Prior Art] In recent years, the storage capacity of data processing devices has increased significantly, and in order to cope with this increase, a method has been adopted in which a large-capacity expansion storage device is added in addition to the main storage device. In such systems, data in a certain storage area (hereinafter simply referred to as an area) within the main storage device is temporarily saved to a high-speed expanded storage device instead of a disk device, or data stored in an expanded storage device is temporarily saved. The system aims to improve system throughput by restoring data to the main memory.

For example, as shown in Figure 2, data in area A in storage device (1) is transferred to area X in storage device (2), and data in area B in storage device (1) is transferred to area X in storage device (1). There may be cases where the data is transferred to area Y. When such data transfer between storage devices is executed using software instructions, one data transfer instruction generally transfers data of a fixed length of N bytes, so the transfer is repeated and executed continuously. By the way, when performing continuous data transfer in block units (N bytes) as shown in Figure 2, a method is adopted in which the data transfer sequences overlap in order to increase the speed. In order to ensure high reliability of the system, the system uses an interrupt to report the abnormal termination to the software, and requests that the area in the storage device that has become abnormal be isolated and retried. .

7 and 8 are diagrams showing an example of such a conventional data transfer method, and FIG. 7 is an explanatory diagram showing the program,
FIG. 8 is the time chart. The program shown in FIG. 7 is for transferring data from area A to area X, from area B to area Y, and from area C to area Z shown in FIG. Transfer between blocks within an area corresponds to one data transfer command. Therefore, commands ■ to ■ specify data transfer from area A to area X, commands ■ to ■ specify data transfer from area B to area Y, and instruction ■ specify data transfer from area C to area Z. become.

The time chart of FIG. 8 shows the time relationship of the data transfer sequence when the end status of the instruction (2) becomes abnormal in the execution of the program of FIG. 7. During the operation of data transfer sequence C (BSYC) of instruction ■,
When sequences A and B of the next instruction ■ are executed in an overlapping manner, an abnormal state accompanying the data transfer of the instruction ■ is detected, and the interrupt reporting (INT) and interrupt processing sequence are activated. The data transfer of instruction ■ has already been executed. Therefore, in this data transfer method, since the software does not accurately grasp the data guarantee range in the event of an actual abnormality, area X, area Y, and area Z are separated, allocated to another area, and restarted from instruction It is necessary to try.

[Problem that the invention seeks to solve]

In the conventional data transfer control method described above, even if the software performs error processing and retry processing when an abnormal event occurs during data transfer, the occurrence point and the next data transfer are executed at the same time. It is difficult for software to recognize and manage which areas within the device are guaranteed to have data transferred, thus preventing efficient and fine-grained error handling, reducing system reliability and reducing system throughput. There were drawbacks that led to a decline.

An object of the present invention is to provide a data transfer control method that can perform flexible and efficient failure handling and retry processing by eliminating the above-mentioned drawbacks, and can construct a system with improved iH performance and system throughput. The purpose is to provide.

[Means for solving problems]

The present invention provides a data transfer control method for controlling data transfer between two different storage areas of a data processing system, in which a synchronization instruction field for instructing data transfer synchronization is set in a command word, and an instruction control unit sends the data transfer execution instruction and the contents of the synchronization instruction field to the data transfer control unit based on the result of decoding the command word, and if the contents of the synchronization instruction field is a synchronization instruction command, the data transfer being executed is terminated. The next execution instruction by the instruction control unit is suppressed until the presence or absence of an abnormal event that has occurred during data transfer is checked.

[For production]

In the present invention, a synchronization instruction field for instructing synchronization of data transfer operations is set in a command word, and a predetermined synchronization instruction command is programmed. Then, in the command control unit that decodes the command word and instructs execution, based on the result of decoding the command word, sends the data transfer execution command and the contents of the synchronization command field to the data transfer control unit,
If the content of the synchronization instruction field is a synchronization instruction command, the next execution instruction in the instruction control unit is suppressed until the completion of the data transfer being executed and the presence or absence of an abnormal event that occurred during the data transfer are confirmed.

In this way, a synchronization instruction is set in the synchronization instruction field so that the software can recognize the instruction retry area for data transfer where there is a risk of data destruction in the storage area due to an abnormal event that occurs during data transfer. , by executing this synchronization instruction instruction at the end of the data transfer instruction for the storage area that the software wants to retry,
The software can recognize and manage the data guarantee range within the storage area, enabling flexible and efficient failure handling and retry processing.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the main points of the configuration of a data processing device to which an embodiment of the present invention is applied. 10 and 20 are different storage devices (1) and (2), and 30 is a storage device (
1) An instruction control unit that takes out the program stored in 10 via path (1) 101, decodes the instruction word, and instructs the execution of the instruction; This is a transfer control unit that executes data transfer between the storage device (1) 10 and the storage device (2) 20 via the path (3) 102 and the path (3) 103.

FIG. 3 is an explanatory diagram showing the format of transfer-related commands used in this embodiment. OP is an instruction code that indicates an operation; for example, WD is a command code that indicates an operation from storage device (1) 10 to storage device (2) 20. A data transfer command, RD, represents a data transfer command from the storage device (2) 20 to the storage device (1) 10. Also, S.Y.C.
' is a synchronization instruction field according to the present invention, and when it is "1", it means that data transfer is performed and synchronization is performed.

AD (1) is the address (
AD (2) is a field that specifies the address (2) for the storage device (2) 20.

FIG. 4 is a flowchart showing an example of the operation of the transfer control section 40 when an execution instruction from the command control section 30 is accepted. FIG. 5 also shows the storage device (1) shown in FIG.
) 10 areas A, B and C on storage device (2)
20 is an explanatory diagram showing an example of an instruction execution sequence when transferring to areas X, Y, and Z of No. 20, respectively. FIG. Further, FIG. 6 is a time chart showing the time relationship of the operations of the transfer control section 40 with respect to the instruction sequence shown in FIG.

A feature of the present invention is that a synchronization instruction field syc' is provided in the instruction word shown in FIG. 3, the synchronization instruction command SYC for data transfer shown in FIG. 1 is set, and control is performed according to the flowchart shown in FIG. Especially. be.

Next, the operation of this embodiment will be explained. First, when the instruction code is WD, the data in the storage device (1) 10 corresponding to the address indicated by the field AD (1) is
It is assumed that the data is transferred to the area of the storage device (2) 20 corresponding to the address indicated by the field AD (2), and when the instruction code is RD, data transfer in the opposite direction is executed.

In FIG. 1, when the command control unit 30 decodes the command code and finds that it is a data transfer command, it issues an execution instruction to the transfer control unit 40 using an execution request signal RQ. At the same time, the request code signal RQC sends the operation code, and the address signal AD sends the operation code to the memory devices (1) 10 and (
2) It sends out the address for 20 and a synchronization instruction command SYC for data transfer using the synchronization instruction field SYC'.

The reply signal RPY is sent from the transfer control unit 40 to the command control unit 3.
When the command control section 30 receives this reply signal RPY, which is a signal corresponding to the execution request signal RQ sent to the command RPY, it instructs the execution of the next command.

The interrupt report signal (NT is the transfer control unit 40's storage device (1
) 10 and (2) 20, or when the transfer control unit 40 itself detects an abnormal state, this signal is reported to the command control unit 30, and the command control unit 30 The unit 30 uses this interrupt report signal INT to suppress the execution instruction of the next instruction and starts the interrupt processing sequence.

Next, the flowchart shown in FIG. 4 will be explained. Step S1
is a step of detecting the execution request signal RQ from the instruction control unit 30, and the execution request signal RQ is "l" (logical "
1), the request code signal R is sent in step S2.
QC, address signal AD and synchronization instruction command SYC
and sequence A busy indicator (BSY
A) is set to "1", and the request code signal RQC
decipher the contents and move on to the next step S3 (sequence A
).

In step 3, reset the sequence A busy indicator (BSYA) to “0” (logic “0”);
Set sequence B busy indicator (BSYB) to “1”
Set to . Also storage devices (1) 10 and (2) 2
0, a data transfer request and a transfer address are sent in accordance with the decoding result of the request code signal RQC, a transferable state is checked, and data transfer sequence control between these two storage devices is synchronized. In step S4, when the synchronization is completed, the next step S5 -
Activate (sequence B).

In step S5, the sequence B busy indicator (BSYB) is reset, the sequence C busy indicator (BSYC) is set to "1", and the storage device (
1) Start data transfer between 10 and the storage device (2) 20. At this time, the value of the synchronization instruction command SYC is checked in step S6, and when rOJ, a reply signal RPY is sent to the command control unit 30 (step S6).
7). In the next step S8, the end of data transfer is awaited (sequence C).

When the end of the transfer is detected, the sequence C busy indicator (BSYC) is reset to "0" in step S9, and the sequence C busy indicator (BSYC) is reset to "0".
D) is set to "1" to start the termination status reception sequence from storage device (1) 10 and second (2) 20. When the end status is fetched, the contents are checked in step 310, and if an abnormality is detected, the instruction control unit 30 is instructed to start an interrupt processing sequence by the interrupt report signal INT in step 11. Next step 31
In step 2, check the contents of the synchronization instruction command SYC and
”, the reply signal RPY is sent to the command control unit 30.
Send out. When the same order instruction command SYC is "0", the reply signal RPY has already been sent out in step S7, so the reply signal RPY is not sent out at this point. Next, in step S14, sequence B
The busy indicator (BSYD) is set to "0" to end the operation (sequence D). The instruction control unit 30 suppresses the instruction to execute the next instruction until the reply signal RPY is sent.

Based on the above explanation, an example of a program for transferring data from area A to area X, from area B to area Y, and from area C to area Z shown in FIG.
As shown in the figure. Transfer between blocks within an area corresponds to one data transfer command. Therefore, commands ■ to ■ specify data transfer from area A to area X, commands ■ to ■ specify data transfer from area B to area Y, and command ■ specify data transfer from area C to area 2. It turns out. This FIG. 5 corresponds to the conventional example shown in FIG. FIG. 6 shows the time relationship of the data transfer sequence when the end status of instruction (■) becomes abnormal in the instruction execution of FIG. 5, and corresponds to the conventional example shown in FIG. 8. .

In this embodiment, as shown in FIG. 5, the synchronization instruction field SYC' according to the present invention allows the software to simultaneously instruct the data transfer synchronization in the data transfer command for the unit in which the area is to be managed. As shown in Figure 6, even if an abnormality is detected in the instruction ■, the instruction to execute the next instruction ■ is suppressed because synchronization is achieved by waiting to send a reply signal until the interrupt processing sequence is activated. Therefore, data transfer by instruction ■ is not executed.

Therefore, the contents of area Z are also guaranteed.

In other words, the software only needs to perform error processing and retry processing for area Y.

〔Effect of the invention〕

As explained above, when data is transferred between different storage areas, the present invention provides an instruction retry area for data transfer in which there is a risk of data destruction in the storage area due to an abnormal event that occurs during data transfer. Set a synchronization instruction field in the instruction word to instruct synchronization of data transfer so that the software can recognize it, and set the synchronization instruction command in the last data transfer instruction of the area that the software wants to retry in advance By doing so, the software can recognize and manage the guaranteed data range within the storage area using relatively simple means, and has the effect of enabling flexible and efficient failure handling and retry processing.

Therefore, according to the present invention, a data processing device with improved reliability and throughput can be obtained, and its effects are significant.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the main points of the configuration of a data processing device to which an embodiment of the present invention is applied. FIG. 2 is an explanatory diagram of data transfer between storage devices. FIG. 3 is an explanatory diagram showing an example of a command word format according to an embodiment of the present invention. FIG. 4 is a flowchart showing a control procedure of a transfer control unit according to an embodiment of the present invention. FIG. 5 is an explanatory diagram showing an example of a program according to an embodiment of the present invention. FIG. 6 is a time chart corresponding to FIG. FIG. 7 is an explanatory diagram showing an example of a conventional program. FIG. 8 is a time chart corresponding to FIG. 7. 10...Storage device (1), 20...Storage device (2)
, 30... instruction control unit, 40... transfer control unit, 10
1... Bus (1), 102... Bus (2), 103
...Bus (3), AD...Address signal, AD
(1), AD (2)...Field, OP...
Instruction code, INT...interrupt report signal, RPY...
Reply signal, RQ...Execution request signal, RQC...
Request code signal, SYC...Synchronization instruction command, S
YC'...Synchronization instruction field, WD...Data transfer command.

Claims (1)

[Claims] (1) In a data transfer control method that controls data transfer between two different storage areas of a data processing system, a synchronization instruction field that instructs data transfer synchronization is set in the instruction word, and the instruction control unit Based on the result of decoding the command word, the data transfer execution instruction and the contents of the synchronization instruction field are sent to the data transfer control unit, and if the contents of the synchronization instruction field are a synchronization instruction command, the data transfer being executed is terminated and A data transfer control method characterized in that the next execution instruction in the instruction control unit is suppressed until the presence or absence of an abnormal event that has occurred during data transfer is checked.