JP2615520B2 - How to check the status of I/O devices - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THEINVENTION The present invention relates to a method for checking the status of an I/O device when a reset channel path (RCHP) command is issued.

In a computer system in which a plurality of input/output devices (I/O) are connected to each of a plurality of channel paths, a central processing unit (CP)
When testing the status of each input/output device (I/O) when the test function task (TAS) issues a channel path reset (RCHP) command, since multiple I/O devices are connected to each channel path, if a test function task testing a certain I/O device issues the channel path reset (RCHP) command by itself, there is a problem that this affects I/O devices that are not related to the test function task.

In addition, each test function task cooperates with the others to select all the channel paths of the computer system,
If the channel path reset (RCHP) command is issued, communication between a plurality of tasks is required to perform exclusive control of the channel path reset (RCHP) command, which results in problems such as complicated control.

For this reason, it is possible to arbitrarily select a channel
A method is required to efficiently test input/output (I/O) devices while issuing a reset path (RCHP) command.

[0005]

5 and 6 are diagrams for explaining a conventional method for checking the status of an input/output device. FIG. 5 shows an example of a computer system configuration, and FIG.
1 is a diagram explaining a test method for the NI 6110/O).

In FIG. 5, each input/output device (I/O) 6 is
The channel device (C) under the channel processing unit (CHP) 3
The I/O control unit (IOC) 5 is connected to the I/O control unit (I/O H) 4, and the central processing unit (CPU) 1 issues an I/O command to the channel processing unit (CHP) 3, the channel unit (CH) 4,
autonomously decodes the input/output command and issues the necessary command
(Read/Write/Sense commands) are issued to the corresponding input/output device (I/O) 6 via the channel path 40 and the input/output control device (IOC) 5 to control each input/output device (I/O) 6 .

Channel Path Reset Related to the Present Invention
The (RCHP) command clears the status of the input/output control unit (IOC) 5 and input/output device (I/O) 6 under the channel path 40 corresponding to the channel path identifier (CHPID) specified by the (RCHP) command.

In order to test any input/output device (I/O) 6 connected to the computer system, the conventional method uses test function tasks A to a shown in FIG.
are prepared, and a central processing unit (CPU) 1 executes each of the test function tasks A to a to test the corresponding input/output device (I/O) 6 .

Therefore, in the test function tasks A to a, a channel path reset (RCH) command is used to interrupt the hardware operations of the input/output control unit (IOC) 5 and the input/output device (I/O) 6.
P) may execute commands.

Conventionally, in testing a channel path reset instruction (hereinafter referred to as an RCHP instruction) that suspends hardware operation, a plurality of test function tasks A to a of a test program are operated.
In the test function tasks a to a, the RCHP command is issued independently to an arbitrary channel path identifier (hereinafter referred to as CHPID), or the test function tasks a cooperate with each other to issue the RCHP command to the channel paths of all CHPIDs in the system.
The implementation has been such that the RCHP command is issued while selecting and controlling 40.

[0011]

In the former method, the test function tasks A to a each independently issue the RCHP command to any channel path identifier (hereinafter referred to as CHPID).
The I/O device affected by the reset process that is connected to the CHPID for which the RCHP command is issued.
There is a problem in that it is difficult to verify the validity of the completion action of 6.

In other words, when and for which CHPID the reset was issued cannot be recognized by any other test function task than the test function task Aa which issued the RCHP command. Normally, when the test function task Aa issues the RCHP command, it becomes impossible to obtain a "device end" interrupt from the input/output device (I/O) 6. However, in other test function tasks B to a,
It is not possible to determine whether the "device end" interrupt is not obtained due to an error in the input/output device (I/O) 6 itself, or whether the interrupt is not obtained by the above RCHP command.

In the latter method, in which the test function tasks A to a work together to issue an RCHP command while selecting and controlling all CHPIDs in the system, exclusive control of the issuance of the RCHP command is required through communication between multiple test function tasks A to a, which complicates the control and increases the processing overhead in the entire test system, resulting in the problem that efficient testing cannot be performed.

In view of the above-mentioned drawbacks of the prior art, the present invention provides a channel path reset command (RCHP) for a computer system in which a plurality of input/output devices (I/O) are connected to each of a plurality of channel paths.
The present invention aims to provide a method for efficiently testing the validity of an input/output (I/O) completion operation when an instruction is issued.

[0015]

1 is a diagram for explaining the principle of the present invention. The above problems are solved by a method for checking the status of an input/output device configured as follows.

A plurality of input/output devices (I/O devices) are connected to each of the plurality of channel paths 40 via the plurality of channel paths 40.
In a computer system to which an input/output device (I/O) 6 is connected, a central processing unit (CPU) 1 issues a channel path reset (RCHP) command, and a method of testing the status of each input/output device (I/O) 6 is provided by separating a channel path reset task and a task for testing the validity of the completion operation of each I/O device from a plurality of test function tasks corresponding to each input/output device (I/O) 6, and storing only one reset task and an I/O device status completion state confirmation task in the system, and storing status bytes 60, 61, of each input/output device (I/O) 6, and I/O device startup information 62 when an input/output command is issued, and a channel path reset (RCHP) command.
The time of occurrence (TOD) is added to the command issue/completion information 63,
The status bytes 60, 61 of the input/output devices (I/O) 6, which are generated and updated in response to the execution of the test function task and the reset task, the I/O device start information 62, and the channel path reset command (RCHP) issue/completion information 63,
In the above I/O device status completion confirmation task, trace in chronological order and check the channel path reset (RCHP)
It is configured to check the validity of the status of each input/output device (I/O) 6 at the time the command is issued.

[0017]

In the present invention, the test function tasks A to
The test processing of the channel path reset (RCHP) instruction is separated from a and made a dedicated task (reset task).
This dedicated task (reset task) then resets all the channel processing units (CHs) that make up the hardware system.
P) 3 Perform a reset test on channel path 40.

Therefore, the channel path 40 can be managed in a unified manner, and the above-mentioned RCHP between the test function tasks A to
In addition, in the present invention, the I/O device (I/O device) affected by the channel path reset is reset.
O) An I/O device status completion state confirmation task (completion confirmation task) for confirming the status of the six groups is separated from the test function tasks A to a and provided exclusively for this purpose.

In the present invention, each input/output device
(I/O) 6 status bytes 60, 61, and I/O device startup information 62 when an I/O command was issued, and channel path reset (RCHP) command issue/completion information 63 show the occurrence date and time.
The status bytes 60, 61, I/O device start information 62, and channel path reset command (RCHP) issue/completion information 63 of each input/output device (I/O) 6 with the above-mentioned occurrence date and time (TOD) that are generated and updated in response to the execution of the test function task and reset task are traced in chronological order by an I/O device status completion state confirmation task independent of the test function tasks A, B, C, and D.
Validates the status of each I/O device at the time the Reset Path (RCHP) command is issued.

The trace information includes input/output command start information 62, RCHP for each input/output device (I/O) 6 when a plurality of test function tasks and a reset task are executed.
The command issue/completion information 63, the interrupt status byte 61, and the end status byte 60 of each I/O device are generated together with the time of occurrence (TOD) and are chronologically traced by the I/O device status completion state confirmation task.
By determining when the I/O device 6 was issued during its operation, the completion status of each I/O device 6 can be calculated using the
It becomes possible to distinguish whether the test was forcibly terminated by a CHP command or whether the test input/output operation was terminated as expected by an input/output command.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to the accompanying drawings. FIG. 1 is a diagram for explaining the principle of the present invention.
3 and 4 show an embodiment of the present invention.
FIG. 3 shows an example of a trace table, and FIG. 4 shows the operation of tracing the above trace table in a time series manner by the I/O device status completion state confirmation task.

In the present invention, in a computer system in which a plurality of input/output devices (I/O) 6 are connected to each of a plurality of channel paths 40 via the channel paths 40, when a central processing unit (CPU) 1 issues a channel path reset (RCHP) command, the status of each input/output device (I/O) 6 is
Each input/output device (I/O) 6 is tested for its status.
From the multiple test function tasks a corresponding to the I/O devices (I/O) 6, the channel path reset task and the task for testing the validity of the completion operation of each I/O device are separated, and a reset task and an I/O device status completion state confirmation task (completion confirmation task) that are unique in the system are provided, and the status byte of each I/O device (I/O) 6 and
I/O device startup information when an I/O command is issued 62, Channel Path Reset Command (RCHP) issue/completion information 63
The means required to carry out the present invention is a means for adding a time of occurrence (TOD) to the status bytes 60, 61, I/O device start information 62, and RCHP issue/completion information 63 of each input/output device (I/O) 6 with the time of occurrence (TOD) which are generated and updated in response to the execution of the test function task and reset task, and tracing the I/O device status completion state confirmation task. Note that the same symbols indicate the same objects throughout the drawings.

[0023] The method of checking the status of an I/O device of the present invention will be described below with reference to Figures 2 to 4 while referring to Figure 1. First, in the present invention, as shown in Figure 1, the reset task is configured independently of the test function tasks A ~ corresponding to each input/output device (I/O) 6, so that in response to the I/O operation by the test function tasks A ~, each channel path 40 is selected by each CHPID as shown in Figure 2, and the channel path 40 is reset.

2, the reset task uses the illustrated channel path management table to centrally manage the reset status of each channel path 40. In the example of Fig. 2, after each channel path (corresponding to CH1 to CH4) 40 has been reset once, it is shown that the reset of channel path (corresponding to CH5) 40 is currently being executed.

Therefore, each test function task A can execute an I/O command without being aware of the RCHP command by other test function tasks B, and communication between the test function tasks A for exclusive processing of the RCHP command is not required, reducing the overhead of the communication. Also, the overhead of referring to and updating the channel path management table can be reduced.

Next, referring to FIG. 3 and FIG. 4, the input/output device (I/O) status completion state confirmation task
The trace operation of the operation completion state is explained as shown in Figure 3(a).
As shown in (b), each I/O device (6) outputs an end status byte (60), an interrupt status byte (61), etc.
In the present invention, the date and time of occurrence (TOD) is added to these status bytes 60 and 61.

In addition, the date and time of occurrence (TOD) is also added to the I/O start information (see FIG. 3(c)) 62 when an I/O command is issued to each I/O device (I/O) 6, and further, the date and time of occurrence (TOD) is also added to the RCHP issue/completion information (see FIG. 3(d)) 63 when an RCHP command is issued.

Therefore, when the present invention is implemented, each time a test function task A is executed, the input/output device (I/O)
The end status byte 60 or the interrupt status byte 61 is updated, and the update date and time (TOD) is recorded.

In addition, each time a reset task that operates independently of the test function tasks A to C is executed, the RCH
P issue/completion information 63, together with its occurrence/completion date and time (TOD), is stored in main storage unit (MSU) 2 (not shown) (see FIG. 5).
is recorded above.

Therefore, as shown in FIG. 4, the I/O device status completion state confirmation task of the present invention chronologically traces the completion state 60 of each I/O device 6 and the RCHP issue/completion information 63, and by analyzing the traced information, it becomes possible to confirm the validity of the status of the I/O device 6 affected by the RCHP command.

For example, when an I/O command is issued to I/O device A by test function task A, if an RCHP command is issued after the date and time (TOD) of the end status, the validity of the command can be confirmed by confirming that the command has ended normally. Also, if the end status is not set, the validity of the command can be confirmed by checking the date and time (TOD) of the issuance/completion of the RCHP command.

In this way, the present invention is directed to a computer system in which a plurality of input/output devices (I/O) 6 are connected to each of a plurality of channel paths 40 via the plurality of channel paths 40, and when a central processing unit (CPU) 1 issues a channel path reset (RCHP) command, the state of each I/O device is
(I/O) 6 Test the status of each I/O device.
From a plurality of test function tasks a corresponding to (I/O) 6,
The channel path reset task and the task that tests the validity of the completion operation of each I/O device are separated, and only one reset task and I/O device status completion state confirmation task are provided in the system.
The status bytes 60 and 61 of the I/O command 6, the I/O device startup information 62 when the I/O command was issued, and the issue/completion information 63 of the channel path reset command (RCHP) contain the occurrence date and time (T
OD) is added, and the occurrence date and time is generated and updated in response to the execution of the above test function task and reset task.
Status byte for each input/output device (I/O)6 with (TOD)
60, 61, I/O device startup information 62, RCHP issue/completion information 63
The I/O device status completion confirmation task traces the channel path reset in chronological order.
A feature of this method is that it checks the validity of the status of each input/output device when the (RCHP) command is issued.

[0033]

As explained above in detail, in the method for checking the status of an input/output device of the present invention, the test for resetting a channel path is made the only dedicated task (reset task) in the test system, so that the management and control of the channel path to be reset can be unified by the reset task, and processing such as communication between test function tasks and updating of the record table becomes unnecessary.
The overhead of processing related to a test that resets a channel path in a test system is eliminated, and the test that resets a channel path is efficiently executed.
In addition to the test function task, an I/O device status completion status confirmation task is provided, which records the status byte of each I/O device (I/O) 6, I/O device startup information when an I/O command is issued, and channel path reset command (RCH
The status byte, I/O device startup information, and RCHP issue/completion information of each input/output device (I/O) 6 with the above-mentioned date and time of occurrence (TOD), which are generated and updated in response to the execution of the above-mentioned test function task and reset task, are traced in chronological order by the above-mentioned I/O device status completion state confirmation task to confirm the validity of the status of each I/O device at the time of issuing the channel path reset (RCHP) command, so that it becomes possible to efficiently confirm the validity of the status of each input/output device (I/O) affected by the channel path reset (RCHP), which was previously difficult.

[Brief description of the drawings]

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

FIG. 2 is a diagram showing an embodiment of the present invention (part 1).

FIG. 3 is a diagram showing an embodiment of the present invention (part 2).

FIG. 4 is a diagram showing an embodiment of the present invention (part 3).

FIG. 5 is a diagram for explaining a conventional method for checking the status of an input/output device (part 1).

FIG. 6 is a diagram for explaining a conventional method for checking the status of an input/output device (part 2).

[Explanation of symbols]

1 Central Processing Unit (CPU) 2 Main Memory Unit
(MSU) 3 Channel processing unit (CHP) 4 Channel device (CH) 40 Channel path 5 Input/output control unit (IOC) 6 Input/output device (I/O) 60 End status byte 61 Interrupt status byte 62 I/O device start information 63 RCHP issue/completion information , a Test function task Reset task I/O device status completion state confirmation task

Claims (1)

(57) [Claims] 1. A method for providing a plurality of channel paths (40) comprising:
Multiple I/O devices on each channel path (40)
In a computer system to which an I/O (6) is connected, the central processing unit (CPU) (1) issues a channel path reset (RCHP).
A method for testing the status of each input/output device (I/O) (6) when a command is issued, comprising: a channel path reset task, and a test function task () corresponding to each input/output device (I/O) (6).
The tasks for testing the validity of the completion operation of each I/O device are separated, and a reset task (), which is unique in the system, and an I/O device status completion status confirmation task () are provided. The status bytes (60, 61) of each I/O device (6) and the I/O device startup information (6) when an I/O command is issued are recorded.
2) The time of occurrence (TOD) is added to the issue/completion information (63) of the channel path reset (RCHP) command, and the above-mentioned input/output devices (I/O devices) that are generated and updated in response to the execution of the above-mentioned test function task () and reset task () are added.
O) (6) Status byte (60,61), I/O device startup information
(62) The channel path reset command (RCHP) issue/completion information (63) is traced in chronological order by the I/O device status completion state confirmation task () to obtain the status of each I/O device at the time of issuance of the channel path reset (RCHP) command.
(6) A method for checking the status of an input/output device, comprising: checking the validity of the status.