JP2000066905A - Method and device for task rising and wait processing in real time os - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the immediacy of the entire real time OS by registering a task with a wait queue at the time of a wait system call and performing no elimination from an executable queue in the wait system call. SOLUTION: At ask B is registered with a wait queue. When a task A issues a wait system call, the task A is registered with the wait queue by a wait queue registering means 104. Next, the task A is set to a wait state to make it an interrupt allowable state and a scheduler is called. The scheduler retrieves an executable queue in which an executable task exists. In a rising system call for a task, a wait queue eliminating means 105 eliminates the task B from the wait queue. An executable queue entry changing means 106 changes the entry order of the task B to the last. And, the scheduler is called.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a real-time OS.
The present invention relates to a system call processing in an (operating system), and particularly to a task wake-up and wait processing method using a system call.

[0002]

2. Description of the Related Art In a conventional real-time OS, in order to improve immediacy in a user system, an interrupt prohibition time in a system call process is configured to be as short as possible. However, queue operation (moving between the executable queue and the wait queue) in the system call processing must be performed in the interrupt disabled state to prevent the same queue from being operated by the system call called from the interrupt processing. No. In particular, regarding the waiting system call, in addition to the queue operation, the determination of the state of the operation target task must be performed in the interrupt disabled section.

An example of a conventional real-time OS is disclosed in Japanese Patent Application Laid-Open No. Hei 8-297581.

According to the invention described in Japanese Patent Application Laid-Open No. Hei 8-297581, in a computer system controlled by a real-time OS, an interrupt that does not affect resource management by the real-time OS can be interrupted even during system call processing. As a result, a technology for enabling an interrupt process that does not need to issue a system call to be processed without delay has been disclosed.

However, even in such a conventional technique, there is still a problem that the interrupt processing for issuing the system call is restricted by the interrupt disable time.

[0006]

As described above, the processing steps of the system call in the conventional real-time OS are as follows: (1) Judge whether the target task is in a waiting state (if not, go to (5)) (2) Change the status of the target task, etc. (3) Delete the target task from the executable queue. (4) Register the target task in the waiting queue. (5) Call the scheduler. Between the steps in ()), interrupts are disabled (it is possible to enable interrupts after (4)) because it is necessary to prevent the same queue from being operated by a system call called from interrupt processing. For this reason, there has been a problem that the immediacy of the entire real-time OS is reduced, that is, the immediacy of the user computer system is reduced.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a method and an apparatus for wake-up and wait processing of a task in a real-time OS realizing an improvement in the immediacy of the whole real-time OS. The point is to provide.

[0008]

In order to achieve the above object, a task wake-up and wait processing device in a real-time OS according to the first aspect of the present invention performs deletion from an executable queue at the time of a wait system call. It is characterized in that it is provided with a means for preventing such a situation.
A task wake-up and wait processing device in a real-time OS according to claim 2 is the task wake-up and wait processing device in a real-time OS according to claim 1, wherein the task is deleted from the executable queue at the time of the wait system call. Means for preventing information from being performed is constituted by a control unit including a data writing unit and a data reading unit for controlling information, and a storage unit which is an area for storing information. . According to a third aspect of the present invention, there is provided a real-time OS task wake-up and wait processing device according to the second aspect, wherein the storage unit includes at least a scheduler process state storage area. , A task identifier storage area. In addition, the real-time O
The task wake-up and waiting processing device in S
In the task wake-up and wait processing device in the real-time OS described in the above, the data writing means is a task identifier storage area changing means for controlling change of the task identifier storage area existing in the storage part, and is present in the storage part. A scheduler processing state storage area change unit that controls change of the scheduler processing state storage area, a wait queue registration unit that registers a task in a wait queue, a wait queue deletion unit that deletes a task from the wait queue,
Executable queue entry changing means for changing the entry order of tasks registered in the executable queue. A task wake-up and wait processing device in a real-time OS according to claim 5 is the task wake-up and wait processing device in a real-time OS according to claim 2, 3, or 4. The scheduler processing state storage area and the task identifier storage area existing in a storage unit are configured to be read into the control unit. A task wake-up and wait processing device in a real-time OS according to claim 6 is the task wake-up and wait processing device in a real-time OS according to claim 4, wherein the control unit is configured to execute a wait system call during a wait system call. The task is registered in the waiting queue by the waiting queue registering means included in the data writing means, and at the time of a wake-up system call, the task is deleted by the waiting queue deleting means and the executable queue entry changing means included in the data writing means. , The task is deleted from the waiting queue and the order of entries in the executable queue is changed. A real-time OS according to claim 7
The task wake-up and wait processing method described in is characterized in that deletion from the executable queue is not performed during a wait system call. A task wake-up and wait processing method in a real-time OS according to claim 8 is the task wake-up and wait processing method in a real-time OS according to claim 7, wherein the task is stored in a wait queue during a wait system call. By registering and deleting tasks from the waiting queue and changing the order of entries in the executable queue during the wake-up system call, deletion from the executable queue in the waiting system call is no longer performed. It is characterized by the following.

[0009]

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

FIG. 1 is a block diagram showing an example of a computer system for realizing a task wake-up and wait processing method in a real-time OS according to the present invention.

As shown in FIG. 1, a computer system for realizing a task wake-up and wait processing method in a real-time OS according to the present invention generally includes a data writing unit 100 and a data reading unit 10 for controlling information.
1 and a storage unit 11 which is an area for storing information.

The storage unit 11 includes a scheduler processing state storage area 107 and a task identifier storage area 108. The data writing means 100 includes a task identifier storage area changing means 102, a scheduler processing state storage area. Change means 103 and waiting queue registration means 10
4, a waiting queue deleting unit 105, and an executable queue entry changing unit 106.

The task identifier storage area changing means 102
The task identifier storage area 108 existing in the storage unit 11 is
The scheduler processing state storage area change unit 103 is a processing unit that stores the scheduler processing state storage area 107 existing in the storage unit 11.
Are respectively changed.

[0014] The waiting queue registration means 104 registers in the waiting queue. FIG. 2 shows a state in which only task B is registered in the waiting queue. In this state,
When the task A is registered in the wait queue by the wait queue registration unit 104, the wait queue enters a state as shown in FIG.

[0015] The waiting queue deleting means 105 performs deletion from the waiting queue. FIG. 3 shows a state in which task B and task A are registered in the waiting queue. In this state, the task A
Is deleted from the waiting queue, the waiting queue is in a state as shown in FIG.

FIGS. 2 and 3 are diagrams showing the registration status of each task in the waiting queue.

Executable queue entry changing means 106
Changes the entry order of the tasks registered in the executable queue. FIG. 5 shows a state in which each task is registered in the executable queue in the order of task A, task B, and task C. In this state,
When the executable queue entry changing unit 106 changes the entry order of the task B to the end of the executable queue, the executable queue enters a state as shown in FIG.

FIGS. 5 and 6 are diagrams showing the entry order of each task registered in the executable queue.

The data reading means 101 includes a storage unit 11
Is read from the scheduler processing state storage area 107 and the task identifier storage area 108 existing in

Next, the overall operation of this embodiment will be described in detail.

As an initial state, a task B is registered in the waiting queue as shown in FIG. 2, and a task A, a task B, and a task C are registered in the executable queue as shown in FIG. It is assumed that the task currently being executed is task A.

First, the operations in the waiting system call, the scheduler, and the wake-up system call for interrupt processing will be described.

When task A issues a wait system call, as shown in FIG.
A determination is made whether to transition to a wait state. If the state does not transition to the wait state, the process proceeds to the processing step 703. In this embodiment, since the state transits to the waiting state, the process proceeds to the processing step 701.

In processing step 701, the task A is registered in the waiting queue by the waiting queue registration means 104.
The configuration of the waiting queue after registration is as shown in FIG. Next, the task A is set to the waiting state in the processing step 702, the interruption permission state is set in the processing step 703, and the scheduler is called in the processing step 704. FIG. 7 is a flowchart showing the operation of the waiting system call.

In the scheduler, as shown in FIG. 8, interrupts are disabled in processing step 800, and
01, the scheduler processing state storage area changing means 103
Thus, the scheduler is set to the processing state in the scheduler processing state storage area 107. In processing step 802, an executable queue in which an executable task exists is searched. In the present embodiment, the executable queue in which task A, task B, and task C are registered is to be searched. The configuration of the executable queue is as shown in FIG.

In processing step 803, it is determined whether the registered task is in a waiting state. Since the task A registered at the head is in the waiting state, the process proceeds to the processing step 804. In processing step 804, the task identifier storage area changing unit 102 sets the task identifier storage area 108. In the present embodiment, the identifier of task B registered after task A is set in task identifier storage area 108.

Next, in processing step 805, an interrupt is enabled,
In processing step 806, interrupts are disabled. It is assumed that an interrupt request is generated in the interrupt enable / disable step, and a wake-up system call for interrupt processing is issued for task B in the interrupt processing. FIG. 8 is a flowchart showing the operation of the scheduler.

In the wake-up system call for interrupt processing,
As shown in FIG. 9, in a processing step 900, it is determined whether the target task is a task to be woken up. In the present embodiment, the task B is in the waiting state, so the processing step 90
Proceed to 1. In processing step 901, the task B is deleted from the waiting queue by the waiting queue deleting unit 105.
The configuration of the waiting queue after deletion is as shown in FIG.

Next, the process proceeds to processing step 902, where the executable queue entry changing means 106 changes the entry order of the task B to the last. The configuration of the executable queue after the change is as shown in FIG. In processing step 903, the state of task B is changed. Processing Step 9
At 04, the data reading unit 101 reads the scheduler processing state storage area 107, and determines whether the scheduler is processing.

In the present embodiment, since the scheduler is in the process, the process proceeds to the process step 905. Processing step 90
In step 5, the data reading means 101 reads the task identifier set in the task identifier storage area 108, and determines whether the read task identifier is the same as the identifier of the task to be woken up.

In this embodiment, since the task B is the same, the task identifier storage area changing means 102 changes the identifier of the task C registered after the task B by the task identifier storage area changing means 102 in the processing step 906. And the wake-up system call for interrupt processing ends. When the wake-up processing system call for interrupt processing ends, thereafter, the interrupt processing also ends, and the processing returns to the scheduler. FIG. 9 is a flowchart showing the operation of the wake-up system call for interrupt processing.

In the scheduler, processing step 8 in FIG.
At 07, the data reading means 101 reads the task identifier from the task identifier storage area 108. In the present embodiment, the identifier of the task C set in the wake-up system call for interrupt processing is read. Next, the determination processing of processing step 803 is performed. Since the task C is in the executable state, the task switching processing in the processing step 808
The task C is set to the execution state, and the execution right is transferred to the task C.

Next, the operations in the waiting system call, the scheduler, and the task wakeup system call will be described. The configuration is the same as in the above embodiment.

As shown in FIG. 7, when the task A issues a wait system call, it is determined in a processing step 700 whether or not a transition is made to the wait state. In the present embodiment,
Since the state transits to the waiting state, the process proceeds to processing step 701. In processing step 701, the task A is registered in the waiting queue by the waiting queue registration unit 104. The configuration of the waiting queue after registration is as shown in FIG. Next, task A is set to a waiting state in processing step 702, and processing step 7
In step 03, the interrupt is permitted, and in step 704, the scheduler is called.

In the scheduler, as shown in FIG. 8, interrupts are disabled in processing step 800, and
01, the scheduler processing state storage area changing means 103
Thus, the scheduler is set to the processing state in the scheduler processing state storage area 107. In processing step 802, an executable queue in which an executable task exists is searched.

In this embodiment, tasks A, B,
The executable queue in which the task C is registered is a search target. The configuration of the executable queue is as shown in FIG. In processing step 803, it is determined whether the registered task is in a waiting state. Since the task A registered at the head is in the waiting state, the process proceeds to the processing step 804.

In the processing step 804, the task identifier storage area 1
08 is set. In the present embodiment, the identifier of task B registered after task A is set in task identifier storage area 108. Next, in step 805, interrupts are enabled, and in step 806, interrupts are disabled.

Subsequently, in processing step 807, the task identifier storage area 108 is
Read task identifier from In this embodiment, the identifier of task B set in processing step 804 is read, and the state of task B is determined again in processing step 803. Since the task B is also in the waiting state, the process proceeds to the processing steps 804, 805, 806, and 807 again. In the processing step 803, the state of the task C is determined. Transfer rights. In task C, a task wakeup system call is issued to task B.

In the task wake-up system call, FIG.
As shown in (1), it is determined in processing step 1000 whether the target task is a task to be woken up. In the present embodiment, since task B is in the waiting state, processing step 100
Proceed to 1. In processing step 1001, the task B is deleted from the waiting queue by the waiting queue deleting unit 105. The configuration of the waiting queue after deletion is as shown in FIG.

Next, the process proceeds to processing step 1002, where the executable queue entry changing means 106 changes the entry order of the task B to the last. The configuration of the executable queue after the change is as shown in FIG. Processing step 1003
Then, the state of the task B is changed. In processing step 1004, interruption is permitted, and in processing step 1005, the scheduler is called. FIG. 10 is a flowchart showing the operation of the task wake-up system call.

As shown in FIG. 8, the scheduler disables the interrupt at processing step 800, and
01, the scheduler processing state storage area changing means 103
Thus, the scheduler is set to the processing state in the scheduler processing state storage area 107. In processing step 802, an executable queue in which an executable task exists is searched.

In this embodiment, tasks A, C,
In addition, the executable queue in which the task B is registered is a search target. The configuration of the executable queue is as shown in FIG.

In processing step 803, it is determined whether the registered task is in a waiting state. Since the task A registered at the head is in the waiting state, the process proceeds to the processing step 804. In processing step 804, the task identifier storage area changing unit 102 sets the task identifier storage area 108. In the present embodiment, the identifier of the task C registered after the task A is set in the task identifier storage area 108.

Next, at step 805, interrupts are enabled, and at step 806, interrupts are disabled. In processing step 807, the data reading means 101 reads a task identifier from the task identifier storage area 108. In the present embodiment, the identifier of the task C set in the processing step 804 is read, and the state of the task C is determined again in the processing step 803. Since the task C is in the executable state, the task C is set to the execution state, and the execution right is transferred to the task C.

[0045]

As described above, according to the present invention,
In the real-time OS, the process of deleting from the executable queue in the waiting system call is not performed, and the interrupt disabling time of the waiting system call is reduced. Therefore, the interrupt disabling time of the waiting system call can be reduced. As a result, the immediacy of the user computer system, which is an important performance index of the real-time OS, can be improved.

In addition, since the immediacy of the user computer system can be improved, the relative processing performance can be improved even if a CPU having a slightly lower processing performance than a conventionally used CPU (such as a lower price) is used. As it is, an inexpensive system can be configured.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an example of a computer system for realizing a task wake-up and wait processing method in a real-time OS according to the present invention.

FIG. 2 is a diagram showing a registration state of each task in a waiting queue.

FIG. 3 is a diagram showing a registration state of each task in a waiting queue.

FIG. 4 is a diagram showing a registration state of each task in a waiting queue.

FIG. 5 is a diagram showing an entry order of each task registered in an executable queue.

FIG. 6 is a diagram illustrating an entry order of each task registered in an executable queue.

FIG. 7 is a flowchart showing the operation of a waiting system call.

FIG. 8 is a flowchart showing the operation of the scheduler.

FIG. 9 is a flowchart showing an operation of an interrupt processing wake-up system call;

FIG. 10 is a flowchart showing an operation of a task wakeup system call.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Control part 11 Storage part 100 Data writing means 101 Data reading means 102 Task identifier storage area change means 103 Scheduler processing state storage area change means 104 Queue registration means 105 Queue deletion means 106 Executable queue entry change means 107 Scheduler processing state Storage area 108 Task identifier storage area

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[Procedure amendment]

[Submission date] July 1, 1999 (1999.7.1)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Change

[Correction contents]

[0008]

According to a first aspect of the present invention, there is provided a task wake-up and wait processing apparatus in a real-time OS.
Data writer and data reader to control information
And a scheduler processing state storage area.
And a storage unit including a task identifier storage area.
Task wake-up and waiting processor in real-time OS
The data writing unit includes a task identifier storage region changing unit that controls change of a task identifier storage region existing in the storage unit, and a scheduler processing state storage region changing unit that controls change of a scheduler processing state storage region existing in the storage unit. And a waiting queue registering means for registering a task in the waiting queue, a waiting queue deleting means for deleting a task from the waiting queue, and an executable queue for changing the entry order of the tasks registered in the executable queue And entry change means. Further, the data reading unit can read the scheduler processing state storage area and the task identifier storage area existing in the storage unit into the control unit. Also, the control unit registers the task in the waiting queue by the waiting queue registration unit included in the data writing unit at the time of the waiting system call, and the waiting queue included in the data writing unit during the wake-up system call. The deletion unit and the executable queue entry changing unit can delete a task from the waiting queue and change the order of entries in the executable queue. A task wake-up and wait processing method in a real-time OS according to claim 4 registers a task in a wait queue during a wait system call,
By deleting a task from the waiting queue and changing the order of entries in the executable queue, deletion of the task from the executable queue by the waiting system call is not performed.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0029

[Correction method] Change

[Correction contents]

Next, the process proceeds to processing step 902, where the executable queue entry changing means 106 changes the entry order of the task B to the last. At this time, next to task B
The task C registered in is stored. The configuration of the executable queue after the change is as shown in FIG. In processing step 903, the state of task B is changed. In processing step 904, the scheduler processing state storage area 107 is read by the data reading means 101, and it is determined whether the scheduler is processing.

[Procedure amendment]

[Submission date] October 12, 1999 (1999.10.
12)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Change

[Correction contents]

[0008]

According to a first aspect of the present invention, there is provided a task wake-up and wait processing apparatus in a real-time OS.
A task wake-up and wait processing device in a real-time OS comprising a control unit including a data writing unit and a data reading unit for controlling information, and a storage unit including a scheduler processing state storage area and a task identifier storage area, The data writing unit includes a task identifier storage area change unit that controls change of the task identifier storage area existing in the storage unit, and a scheduler processing state storage area that controls change of the scheduler processing state storage area existing in the storage unit. Change means, wait queue registration means for registering a task in the wait queue, wait queue deletion means for deleting a task from the wait queue, and execution for changing the entry order of tasks registered in the executable queue Means for changing possible queue entries , wherein the data
Reading means for storing the schedule stored in the storage unit;
And a task identifier storage area.
While reading into the control unit, the control unit waits
In a system call, the data writing means
By the waiting queue registration means included in
Register the task, and at the time of wake-up system call
Deletes the waiting queue included in the data writing means
Means and said executable queue entry changing means,
Delete tasks from the waiting queue and
By changing the entry order, the wait system call
It is characterized in that deletion from the executable queue is not performed . A task wake-up and wait processing method in a real-time OS according to claim 2 registers a task in a wait queue during a wait system call, and deletes and executes a task from the wait queue during a wake-up system call. By changing the order of entries in the queue, deletion from the executable queue by a waiting system call is not performed.

Claims (8)

[Claims] 1. A task wake-up and wait processing apparatus in a real-time OS, comprising means for preventing deletion from an executable queue at the time of a wait system call. 2. A means for preventing deletion from the executable queue at the time of the waiting system call, comprising: a control unit including data writing means for controlling information and data reading means; and an area for storing information. The apparatus for wake-up and waiting for a task in a real-time OS according to claim 1, wherein the apparatus comprises: a storage unit; 3. The task wake-up and waiting process in the real-time OS according to claim 2, wherein the storage unit includes at least a scheduler processing state storage area and a task identifier storage area. apparatus. 4. The data writing unit includes: a task identifier storage area change unit that controls change of the task identifier storage area existing in the storage unit; and a change control of the scheduler processing state storage area existing in the storage unit. Scheduler processing state storage area changing means, waiting queue registering means for registering a task in the waiting queue, waiting queue deleting means for deleting a task from the waiting queue, entry order of tasks registered in the executable queue 4. The task wake-up and wait processing device in the real-time OS according to claim 3, further comprising: an executable queue entry change unit that changes the task. 5. The data reading unit according to claim 2, wherein the scheduler processing state storage area and the task identifier storage area existing in the storage unit are read into the control unit. 4. The apparatus for awakening and waiting for a task in the real-time OS according to 4. 6. The control unit registers a task in a waiting queue by a waiting queue registration unit included in the data writing unit during a waiting system call, and writes the data in a waiting system call during a wake-up system call. 5. The real-time OS according to claim 4, wherein the task is deleted from the waiting queue and the order of entries in the executable queue is changed by the waiting queue deleting means and the executable queue entry changing means included in the means. Task wake-up and waiting processor. 7. A task wake-up and wait processing method in a real-time OS, wherein deletion from an executable queue is not performed during a wait system call. 8. At the time of a waiting system call, a task is registered in a waiting queue, and at the time of a wakeup system call, a task is deleted from the waiting queue and the order of entries in the executable queue is changed. 8. The method according to claim 7, wherein the task is not deleted from the executable queue by the waiting system call.