JPH02105227A - System for informing even attending with input/output operation in virtual computer system - Google Patents

Abstract

PURPOSE:To reduce an overhead at the time of informing the event of an input/output operation by a virtual computer to both the virtual computer and a real computer by providing a register in which the address of a notice destination in the real computer and that of the notice destination in the virtual computer, etc., are stored. CONSTITUTION:The address 41 of the notice destination in the real computer 1, the number 42 of the virtual computer 8, the address 43 of the notice destination in the computer 8, and an input/output channel number 44 on the computer 8 are stored in each entry of the register 4 in the real computer 1. Thereby, when the event attending with the input/output operation in the computer 8 is generated, a message related to a generated event is informed to the notice destination 3 in the computer 1 based on a content held at the register 4 corresponding to the unit of the input/output operation related to the generated event by firmware, etc. Also, the message in which an input/output channel number on the computer 8 is converted to the input/output channel number on a specified computer 8 is informed to the notice destination on the specified computer 8. In such a manner, it is possible to reduce the overhead at the time of informing the event according to the input/output operation in the computer 8.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a virtual computer system, and in particular, the present invention relates to a virtual computer system, and in particular, the present invention relates to a virtual computer system, in which events occurring in conjunction with input/output operations initiated by instructions executed on a virtual computer are This relates to a method of notifying both notification destinations within a virtual machine.

[Conventional technology]

FIG. 5 shows the configuration of a virtual computer system using the conventional event notification method. This virtual computer system has a real computer 1 and an input/output device 2, and multiple virtual computers 8 are operated on the real computer 1. It has been realized.

The real computer l has notification destinations 3. Register 4.
Software table 5 and channel program 9
There is a notification destination 7 in the virtual machine in the virtual machine 8.
and channel program 6. Generally, in a virtual computer system, input/output operations are realized by the real computer 1 or the virtual computer 4!18 instructing the input/output device 2 to execute the channel programs 9, 6 on the main memory.

First, a case will be described in which the actual computer 1 instructs input/output operations.

The software of the real computer 1 prepares in the main memory a notification destination 3 of an event and a channel program 9 that sets the notification destination 3 as a notification destination of an event associated with an input/output operation, and sends a channel to the input/output device 2. When the execution of the program 9 is instructed, the hardware and/or firmware (hereinafter abbreviated as firmware) of the virtual computer system sends the address of the notification destination 3 of the event specified by the channel program 9 as the unit of the current input/output operation. (for example, in units of logical channels). Thereafter, some event occurs regarding the execution of the input/output operations specified in the channel program 9, such as termination.

When an event such as an intermediate or caution 1 exception occurs, the firmware of the virtual computer system sends the notification destination 3 of the event stored in the register 4 corresponding to the input/output unit related to the event.
, and notifies the event message to the notification destination 3. The message notified at this time includes the input/output channel number targeted for the input/output operation. Note that when the notification destination 3 is a semaphore, the semaphore includes at least information indicating the storage location of the event message and the process that should be activated when the event occurs, and when the event message is notified to the semaphore, The corresponding process is started.

Next, a case where the virtual machine instructs input/output operations will be described.

The software in the virtual machine 8 communicates with the event notification destination 7,
A channel program 6 that specifies the notification destination 7 as the notification destination of events associated with input/output operations is prepared in the main memory, and when the input/output device 2 is instructed to execute the channel program 6, this triggers the program execution. An interrupt occurs and processing is transferred to the software of the real computer 1 (for example, a virtual computer monitor). The above software of real computer 1 is
The virtual computer 8 is used as the notification destination for events from the I/O large bag N2.
A notification destination 3 different from the event notification destination 7 in the virtual computer 8 specified as the event notification destination by the channel program 6 in the real computer 1 is prepared in the main memory of the real computer 1. Further, input/output channel numbers are assigned independently to the real computer 1 and the virtual computer 8. In other words, the input/output channel number on the virtual computer 8 and the human output channel number on the real computer 1 do not always match, so the input/output channel number on the virtual computer 8 and the input/output channel number on the real computer 1 The correspondence with the output channel number is memorized and the actual computer 1 is used when notifying an event.
It is necessary to use different input/output channel numbers in the event message between the virtual machine 8 and the virtual machine 8. For this purpose, the software of the real computer 1 adds the address of the event notification destination 3, the number assigned to the virtual computer 8 in advance (virtual computer number), and the address of the event notification destination 7 in the virtual computer 8. , the input/output channel numbers on the virtual machine 8 are stored in the software table 5. Then, it specifies the notification destination 3 as the event notification destination and instructs the input/output device 2 to execute the channel program 6 in the main memory of the virtual machine 8. As a result, the firmware of the virtual computer system stores the address in the real computer 1 of the event notification destination 3 in the register 4 in correspondence with the unit of the current input/output operation.

After that, when some event occurs due to an input/output operation and is reported, the firmware of the virtual machine system updates the contents of the register 4 corresponding to the unit of input/output operation related to the event (notification destination 3). address),
Notify destination 3 of the event message. As a result, the processing shifts to the software (process) of the actual computer 1 that has been waiting for notification of the event to the notification destination 3. In addition, in the event message notified to the notification destination 3, the input/output channel number on the actual computer l of the input/output channel that was the target of the corresponding input/output operation is displayed.

Next, the above software of the actual calculation 4411 started by the notification of the event to the notification destination 3 refers to the table 5 of the software, and uses the input/output channel number in the above event message as the input/output channel number on the virtual calculation elB. The event message is converted into a channel number, and the event message is notified to the notification destination 7 in the main memory of the virtual machine 8 according to the number of the virtual machine 8 in the software table 5 and the address of the notification destination 7. As a result, the processing is transferred to the software (process) of the virtual machine 8 that has been waiting for notification of the event to the notification destination 7.

As described above, the virtual machine 8 is notified of an event associated with an input/output operation activated by a command from the virtual machine 8.

In this manner, in the conventional virtual computer system, event notifications by the firmware of the virtual computer system, etc. are always sent to the notification destination of the real computer 1.

[Problem to be solved by the invention]

By the way, in a virtual computer system, it may be necessary for a management program on a real computer to always recognize the state of an input/output operation that the virtual computer has instructed to execute.

To do this, when a virtual computer instructs the execution of a channel program, control is transferred to the real computer and the real computer manages the execution of input/output operations, and the input/output operations executed according to instructions from the virtual computer It is necessary to notify both the real computer and the virtual computer of the event associated with this.

In this way, when attempting to notify both the real computer and the virtual computer of events associated with the input/output operations of the virtual machine, in conventional virtual computer systems, the firmware etc. After that, the software on the real computer converts the human output channel number in the event message to the input/output channel number on the virtual computer, and then sends the notification to the notification destination on the virtual computer. Therefore, when notifying an event associated with an input/output operation, a virtual computer takes more time than a real computer due to the intervention of the real computer's software, and the virtual computer's input/output operation overhead increases.

An object of the present invention is to reduce the overhead when notifying notification destinations in both the real computer and the virtual computer of events that occur due to input/output operations activated by instructions executed on a virtual computer. be.

[Means to solve the problem]

The method for notifying events associated with input/output operations in a virtual computer system of the present invention is a system for notifying events associated with input/output operations in a virtual computer system that implements multiple virtual computers on a real computer. Corresponding to the unit, first information identifying the virtual computer, second information indicating the input/output channel number on the virtual computer, and information in the real computer to which events associated with the input/output operation should be notified. Storage means is provided for holding third and fourth information indicating the storage locations of the two notification destinations in the virtual computer, and when an event associated with the input/output operation occurs, the firmware of the virtual computer system , a message related to the event that occurred to a notification destination within the actual computer at a storage location indicated by the third information held in the storage means corresponding to the unit of input/output operation related to the event that occurred; At the same time, the input/output channel number in the message is converted to the input/output channel number on the virtual machine indicated by the second information, and the message is sent to the virtual machine specified by the first information. It has a configuration that notifies the notification destination of the storage location indicated by the information No. 4.

[Effect]

In the event notification method associated with an input/output operation in a virtual computer system of the present invention, when an input/output operation is started by an instruction executed on a virtual computer, a storage device is is first information that identifies the virtual computer, second information that indicates the input/output channel number on the virtual computer, and information within the real computer and virtual computer that should be notified of events associated with the input/output operation. holds third and fourth information respectively indicating the storage locations of the two notification destinations, and when an event associated with the input/output operation occurs,
The firmware or the like of the virtual computer system causes the occurrence of the above-mentioned event to occur at a notification destination within the real computer at the storage location indicated by the third information held in the storage means in response to the input/output operation related to the event that has occurred. The virtual computer specified by the first information notifies the message related to the event and also sends a message in which the human output channel number in the message is converted to the input/output channel number on the virtual computer indicated by the second information. A notification is sent to the notification destination at the storage location indicated by the fourth information.

[Example] Next, an example of the present invention will be described in detail with reference to the drawings.

Referring to FIG. 1, an embodiment of a virtual computer system to which the present invention is applied has a real computer 1 and an input/output device 2, and a plurality of virtual computers 8 are realized on the real computer 1.

Real computer 1 has notification destination 3 within the real computer. Register 4. There is a channel program 9, and the virtual machine 8 has a notification destination 7 and a channel program 6 within the virtual machine. The register 4 is a collection of entries corresponding to a unit of input/output operation (for example, a logical channel unit) activated by an instruction executed on the real computer 1 or the virtual computer 8, and each entry includes a notification in the real computer. Destination address 41. Virtual machine number 42. Notification destination address within the virtual machine 43.
A human output channel number 44 on the virtual machine is stored. Here, the virtual machine number 42 is a number when a number starting from 1 is given to a plurality of virtual machines 8 realized within the virtual machine system. Further, when the virtual machine number is 0, it indicates that the input/output operation is instructed by the real computer l.

Next, with reference to FIG. 1, FIG. 2, and FIG. 3, the operation when the virtual machine instructs input/output operations will be described.

The software in the virtual machine 8 communicates with the event notification destination 7,
A channel program 6 that specifies the notification destination 7 as the notification destination of an event associated with an input/output operation is prepared in the main memory, and the channel program 6 is executed for the input/output device 2 as shown in step Sl in FIG. When this instruction is given, a program interrupt is generated and the processing is transferred to the software (virtual computer monitor, etc.) of the real computer I.

The above software on the real computer l uses a number (virtual computer number) assigned in advance to the virtual computer 8 as the event notification destination.
, the address of the event notification destination 3 in the real computer 1, the address of the event notification destination 7 in the virtual computer 8 specified by the channel program 6 in the virtual computer 8, and the human output on the virtual computer 8. The input/output device 2 is instructed to execute the channel program 6 in the main memory of the virtual machine 8 by specifying the channel number. This operation actually involves the number of the virtual machine 8, the address of the channel program 6, the address of the event notification destination 3 in the real computer 1, and the event notification in the virtual computer 8, as shown in step Sll in FIG. This corresponds to the real computer 1 executing a software instruction that takes the address of the notification destination 7 and the input/output channel number on the virtual computer 8 as arguments, respectively.

By executing the above software instructions,
The firmware, etc. of the actual computer is shown in box B in Figure 2.
1, the address of the event notification destination 3 in the real computer 1, the number of the virtual computer 8 to which notification is to be made, and the virtual computer 8
41 in FIG.
Store as ゜42.43.44.

After this, when an event related to input/output operation occurs and is reported, the firmware of the virtual computer system communicates with the notification destination 3 by performing the operations described below with reference to FIG. The notification destination 7 is notified of the event message at the same time.

First, when an event is reported, the event message is sent to the notification destination 3 according to the address 41 of the notification destination 3 in the real computer 1 in the entry corresponding to the input/output operation unit related to the event in the register 4. (Box B11). Note that during this event message, the actual
9, which includes the above input/output channel number. Next, it is determined whether the virtual machine number 42 in the corresponding entry in the register 4 is 0 or not (box B12). If it is 0, the current operation is ended. In this case, the virtual machine number 42 is a value corresponding to virtual machine 8 and is not 0, so proceed to box B13 and send an event message using the input/output channel number 44 on virtual machine B in the corresponding entry in register 4. In box B14, the event message is notified to the notification destination 7 according to the reflection computer number 42 and the address 43 of the notification destination 7 in the second entry in the register 4. In this way, without the intervention of the software of the real computer 1,
Events from the input/output device 2 are notified to the real computer 1 and the virtual computer 8 simultaneously and directly.

On the other hand, a case where the real computer 1 instructs input/output operations will be explained with reference to FIGS. 1, 3, and 4.

First, the software of the real computer 1 prepares in the main memory a notification destination 3 of an event and a channel program 9 that specifies the notification destination ζ as a notification destination of an event associated with an input/output operation.
For the input/output bag N2, a notification destination 3 of an event in the actual computer l,
The channel program 9 is instructed to be executed by specifying a virtual machine number with a value of 0. In reality, this is a software command that takes as arguments the virtual machine number = 0, the address of the channel program 9, and the address of the event notification destination 3 in the real computer 1, as shown in step S21 in FIG. This corresponds to the actual computer 1 executing.

By executing the above software instructions,
The firmware, etc. of the actual computer 1 is located in box B in Figure 4.
21, the address of the notification destination 3 of the event in the real computer 1 and the virtual machine number -0 are stored in one entry of the register 4 in the first entry in correspondence with the unit of the current input/output operation.
It is stored as 41 and 42 in the figure. Note that at this time, any value may be stored in 43.44 in register 4.

After that, when some event occurs regarding the execution of the input/output operation specified by the channel program 9 and is reported, the firmware of the virtual computer system performs the operation shown in FIG. , an event message is notified to the notification destination 3 according to the address 41 of the notification destination 3 in the real computer 1 in the entry corresponding to the input/output unit related to the event in the register 4. This event message includes the input/output channel number on the real computer 1. Next, it is determined whether the virtual computer number 42 in the corresponding entry in the register 4 is 0 or not (box B12), 0. Therefore, this operation ends.

In addition, in a system in which input/output operations are performed in correspondence with logical channels, register 4 is used for conversion to correspond the logical channel number seen from the real computer, the virtual computer number, the notification destination address, and the channel number on the virtual computer. It is also possible to provide it in the form of a table in a protected area on main memory.

〔Effect of the invention〕

As explained above, according to the event notification method associated with the input/output operation of the virtual computer system of the present invention, even when the input/output channel number is different from the perspective of the real computer and the virtual computer, Notifications of events associated with input/output operations within a virtual computer are now directly sent to both the real computer and the virtual computer through a one-step notification operation that does not require intervention from the software of the real computer. This has the effect of reducing the overhead of input/output operations.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of an embodiment of a virtual computer system to which the present invention is applied, and Fig. 2 shows the software on the virtual computer, the software on the real computer, and the virtual computer system when the virtual computer instructs input/output operations. Figure 3 is a flowchart showing an example of the processing performed by the firmware, etc. of a virtual computer system when an event associated with an input/output operation occurs, and Figure 4 is a flowchart showing an example of the processing performed by the firmware, etc. of a virtual computer system when an event associated with an input/output operation occurs. FIG. 5 is a block diagram of a conventional virtual computer system. In the figure, l... Real computer 2... Input/output device 3... Notification destination in real computer 4... Register 41... Address of notification destination in real computer 42... Virtual computer number 43...Address of the notification destination in the virtual machine 44...
Input/output channel number on virtual machine 5...Software table 69...Channel program 7...Notification destination in virtual machine 8...Virtual computer

Claims (1)

[Claims] In a virtual computer system that realizes a plurality of virtual computers on a real computer, a virtual computer is identified in correspondence to a unit of input/output operation activated by an instruction executed on the virtual computer. 1st
information, second information indicating the input/output channel number on the virtual computer, and storage locations of two notification destinations within the real computer and within the virtual computer to which events associated with the input/output operation should be notified, respectively. storage means is provided to hold third and fourth information indicating the input/output operation, and when an event associated with the input/output operation occurs, the hardware and/or
Or, by firmware, a notification destination in the actual computer at a storage location indicated by the third information held in the storage means corresponding to the unit of input/output operation related to the occurred event is sent to the notification destination in the real computer. In addition to notifying such a message, a message in which the input/output channel number in the message is converted to the input/output channel number on the virtual machine indicated by the second information is sent to the virtual machine specified by the first information. A notification method of an event associated with an input/output operation in a virtual computer system, characterized in that a notification destination of a storage location indicated by the fourth information is notified.