JP2007041890A - Task control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To implement event processing in consideration of delay time and frequency after occurrence of event, and facilitate changes in deadline thresholds. <P>SOLUTION: When triggered by an external tool/different device 86, a measurement module 84 adjacent to a task control part 81 measures delay times caused for each event, and records the measurements in a level determining measurement table by measurement patterns to allow them to be output to the external tool/different device 86. Appropriate deadline thresholds are set to update a level determining threshold table 82 according to the measurements. With the external tool/different device 86 in connection with an external communication interface, set values in the level determining threshold table 82 can be easily updated via a rewriting module 83. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a task control device, and more particularly to a task control device that controls event processing according to a deadline level of an event notification delay time on a task side in event notification to a task in a real-time OS.

In general, a real-time OS that realizes interrupt processing in real-time control, an input / output interface function with a general-purpose peripheral device, or the like is used as an OS (Operating System) such as a monitoring control device that requires real-time processing. It has been.
As for the task (task) which is a program for executing various control processes on the real-time OS, it is natural that real-time processing is required, and all tasks on the real-time OS are limited. It has become necessary to process within a given time. In order to satisfy this requirement, task scheduling algorithms and the like have been improved, and processing efficiency has been improved.
As an example of such a method that can process the operation of a task on the real-time OS within a limited time, the task switching frequency is reduced in the real-time OS that schedules a periodic task that is repeatedly executed at regular time intervals. However, there is a technique that suppresses the occurrence of a so-called deadline violation in which processing in a task does not end within a limited time (see, for example, Patent Document 1).
When a task arrives, it is determined whether to schedule the task according to the load state of the CPU at the time of arrival, and an overload is prevented in advance. In the second and subsequent times, the adaptive deadline is updated so as to shorten the communication waiting time obtained from the result of executing the task, so that it can be adapted to a dynamic environment and the CPU is used effectively. There is one that can be used (for example, see Patent Document 2).
Also, the delay time from the event occurrence point in the real-time OS is notified to the task side as an event notification, and the task side determines the deadline level of the delay time and selects an appropriate process (program module) according to the determination level It is possible to create a processing program that makes it possible to recognize deadline anomalies on the task side and to avoid system failures due to deadline anomalies in advance according to the stage of the deadline anomaly on the task side. (For example, refer to Patent Document 3).
JP 2001-236236 A JP 2001-350639 A Japanese Patent Laid-Open No. 2004-070582

However, with the conventional technology, even if the processing efficiency of the real-time OS is improved, a deadline abnormality occurs due to processing delay (latency) in the case of an overload state or when the load state continues and becomes a congestion state To do. Even when the task recognizes a deadline abnormality, the load state is not resolved immediately, so a continuous deadline abnormality continues to occur, and the same abnormality handling process is repeatedly executed. In addition, it is difficult to change or adjust the threshold value again when the CPU speed is changed or the process is changed.
That is, the conventional technique has the following problems.
The first problem is that when a deadline abnormality occurs, the task side continues the load state and repeatedly executes the same abnormality handling process. The reason is that when an event occurs at the same time in a task with the same priority level from the occurrence of an event recognized on the real-time OS until it is actually processed on the task side (delay: latency), When there are many events in the task, the event wait time to the task side occurs, and even if the processing is distributed according to the deadline abnormality level in the delay time, the load state will continue, so it will be dead as well This is because events of the line abnormality level occur frequently, and event processing corresponding to the same abnormality repeatedly executes processing.
The second problem is that the deadline threshold cannot be easily set when program design, process change, or addition occurs. The reason is that when the processing time changes due to CPU speed and hardware specifications, it is difficult to set the deadline threshold of each detailed processing for the entire processing time, and when there is a change This is because the adjustment cannot be easily performed.
The present invention has been made in view of such a situation, and notifies the information about the delay time and the number of delay occurrences generated in the task control on the real-time OS from the actual event occurrence time to the event processing on the task side. By doing so, it is an object to enable normal normal processing, abnormal processing, and deadline abnormal processing to be performed on the corresponding task side. It is another object of the present invention to make it possible to easily change the deadline threshold.

The task control device according to claim 1 executes a real-time OS that realizes interrupt processing in real-time control, an input / output interface function with a peripheral device, and the like, and event processing detected by the real-time OS on the real-time OS A task control device comprising a plurality of tasks, measuring means for measuring the delay time notified to each task in a load state, measurement result storage means for storing the measurement results by the measurement means for each event, An output means for outputting a measurement result to an external device, an update means for setting a deadline threshold value based on the measurement result and updating a threshold table for level determination, and a task are notified from the real-time OS. Based on the delay time from the time of the event occurrence, the deadline level of the delay time is determined based on the threshold table for level determination And executes the selected processing program corresponding to the number of occurrences of each level and each level, characterized in that it comprises an event processing means for processing the events.
In addition, the real-time OS includes a task control unit that issues an event notification to any task that processes an event when the occurrence of the event is detected. The event event processing unit of the task includes an event notification attached to the event notification. Level determination threshold table for determining the level of the deadline of the delay time according to the delay time from the occurrence, the continuous occurrence count table for storing the number of continuous occurrences at each level, the level and the number of occurrences of the level And an event execution processing matrix table for selecting a processing program according to the above.
Further, an external communication interface for controlling communication with an external tool or an external device is further provided, and the threshold table for level determination is updated from the external tool or the external device via the external communication interface. Can do.
In addition, the threshold table for level determination has a configuration in which event numbers are arranged in the row direction and deadline levels are arranged in the column direction, and each level for the delay time is set at the intersection of each row and column. Threshold values are defined, and the event execution processing matrix table has a configuration in which event numbers are arranged in the row direction and deadline levels are arranged in the column direction, and the event number is at the intersection of each row and column. It is possible to define a module name of a processing program that executes event processing at different levels for each number of occurrences.
In addition, the event processing means receives the event notification from the task control means, and when any task that executes the event processing of the event number attached to the event notification is activated, the task is set to the threshold for level determination. Refer to the table to determine the deadline level of the delay time of the event number, and then the task refers to the event execution processing matrix table and selects the module name corresponding to the event number level and the number of occurrences. By passing control to a processing program having a module name and executing it, it is possible to perform processing of the event numbered event.
The task control method according to claim 6 executes a real-time OS that realizes interrupt processing in real-time control, an input / output interface function with a peripheral device, and the like, and event processing detected by the real-time OS on the real-time OS. A task control method in a task control device comprising a plurality of tasks, a measurement step for measuring a delay time notified to each task in a load state, and a measurement result for storing the measurement result in the measurement step for each event A storage step; an output step for outputting a measurement result to an external device; an update step for setting a deadline threshold based on the measurement result and updating a threshold table for level determination; Depending on the delay time from the occurrence of the event notified from And determining a deadline level of the delay time, and selecting and executing a processing program according to each level and the number of occurrences of each level, and an event processing step for processing an event. And
The task control program according to claim 7 executes a real-time OS that realizes interrupt processing in real-time control, an input / output interface function with a peripheral device, and the like, and event processing detected by the real-time OS on the real-time OS A task control method in a task control device comprising a plurality of tasks, a measurement step for measuring a delay time notified to each task in a load state, and a measurement result for storing the measurement result in the measurement step for each event A storage step; an output step for outputting a measurement result to an external device; an update step for setting a deadline threshold based on the measurement result and updating a threshold table for level determination; The threshold value threshold for level judgment is based on the delay time from the occurrence of the event notified by And an event processing step for processing an event by determining a deadline level of the delay time based on the level and selecting and executing a processing program corresponding to each level and the number of occurrences of each level. It is characterized by.

According to the present invention, the delay time notified to each task is measured in a load state, the measurement result is stored for each event, the measurement result is output to an external device, and the deadline threshold value is based on the measurement result. The level determination threshold table is updated, and the delay time deadline based on the level determination threshold table is determined based on the delay time from the occurrence of the event notified by the real-time OS. Since the event is processed by determining the level of the event and selecting and executing the processing program according to each level and the number of occurrences of each level, it corresponds to the delay time and the number of occurrences from the event occurrence Event processing can be executed.
Further, the level determination threshold table can be updated from the external tool or the external device via the external communication interface that controls communication with the external tool or the external device.

  The task processing method according to the task notification of the task event notification delay time of the present invention has a priority level from the event occurrence (S15 in FIG. 1) to the event notification to the task 11 side (S18 in FIG. 1) in the real-time OS 12. Waiting for task execution with a low priority, waiting for execution due to contention in the same task with the same priority level, and event notification waiting time for consecutive occurrences of wait events within the same task are measured, and the task control unit 27 performs an event to the task 21 side. Event notification with an event notification delay time added is performed at the time of notification. On the task 21 side, the deadline level of the delay time for each event is determined based on the notified event notification delay time (S22 in FIG. 2), and the number of continuous occurrences corresponding to the level is counted. When the same deadline level is continued, an event execution processing function label 63 corresponding to the event processing is defined for each continuous occurrence number determination formula 62 corresponding to the number of occurrences as shown in FIG. Execute the process.

  Here, the deadline is a time limit from the time of event occurrence to the completion of event processing in the task 21. In other words, there is a time limit determined by the corresponding device or system from the time when an event occurs until the event processing for that event ends, and the end of the event processing exceeds the time limit There is a deadline abnormality.

  In the deadline threshold value setting method of the present invention, various delay times are measured from the external tool / other device 86 via the external communication interface (I / F) 85 in order to set an appropriate value. It is possible to make settings from an external tool / other device 86.

  On the task 21 side, the deadline level is <level 1> normal processing (S23 in FIG. 2), <level 2> normal normal processing (1), normal normal processing (2) (S24, S25 in FIG. 2), < Level 3> abnormal processing (1) (S26 in FIG. 2), <level 4> abnormal processing (2) are defined in stages, and the processing is further classified according to the number of occurrences at the same level (<level 2>). The first time (X = 1) is normal order processing (1) (S24 in FIG. 2), and <level 2> second and subsequent times (X> 1) are normal normal processing (2) (S25 in FIG. 2).

  A level determination threshold value table 31 (76, 82) for determining a threshold value for each delay time level for each event is created. Further, the same matrix structure has a continuous occurrence count table 41 (77) for counting the number of times of occurrence continuously for each event level. When the same deadline level repeatedly occurs in the same event, the count is incremented. If a level change occurs, the previous level count is cleared.

  An event execution processing matrix table 51 (61) is created that defines event processing names so as to jump to processing according to the corresponding level and the number of occurrences.

  In the event execution preparation process of task 21 (S71 in FIG. 7), the deadline level of the corresponding event is obtained from the level determination threshold table 76 from the event notification delay time added at the time of event notification from the task control unit 27. (Determine the matrix position) (S72 in FIG. 7), update the counter of the corresponding continuation occurrence count table 77 (S73 in FIG. 7), and execute the event execution processing matrix according to the obtained deadline level and the corresponding number of continuation occurrences The corresponding event process in the table 78 is called (S74 in FIG. 7) and executed.

  Normal processing (S23 in FIG. 2) if notification delay time from event occurrence 15 is within threshold 1 (level 1), normal if greater than threshold 1 and within threshold 2 (level 2) If the number of occurrences is the first time (X = 1), the normal order process (1) (S24 in FIG. 2), and if the number of occurrences is the second or later (X> 1), the normal order process (2) ( In S25 of FIG. 2, if <level 3> is greater than the threshold value 2, the abnormal process (1) (S26 of FIG. 2) and the process can be separated.

  The delay time is measured by applying a trigger from the external tool / other device 86. That is, the delay time generated for each event is measured by the measurement module 84 adjacent to the task control unit 81, and the measurement result is recorded for each measurement pattern in the level determination measurement table 91 shown in FIG. Output to another device 86 is enabled. An appropriate deadline threshold value is set according to the measurement result, and the level determination threshold value table 31 (82) is updated. That is, it becomes possible to update the deadline threshold table (level determination threshold table) 31 (82) from the rewrite module 83 via the external communication interface 85 from the external tool / other device 86.

  Next, embodiments of the present invention will be described in detail with reference to the drawings.

  Referring to FIG. 1, the embodiment of the present invention includes a task 11 and a real-time OS 12 in software installed in a monitoring control device or the like. In the real-time OS 12 from the occurrence of an event (S15 in FIG. 1) to the event notification to the task 11 side (S18 in FIG. 1), in the task execution waiting with a low task priority level or in competition with the same task at the priority level There is an event notification waiting time for continuous occurrence of waiting events in the same task.

  Referring to FIG. 2, when an event notification with an event notification delay time is performed at the time of event notification from the task control unit 27 to the task 21 side, the task 21 side has each event according to the notified event notification delay time. The deadline level of the delay time is determined (S22 in FIG. 2), and event processing corresponding to the level is executed.

  The definition of the processing level for the notification delay time may vary depending on the system. However, the level is generally set to level 1 when there is no problem as a delay time on the system, and normal processing (S23 in FIG. 2) is performed to recognize the delay. In the case where the level is satisfactory even if reprocessing is performed, the level is set to level 2, and if the number of occurrences is the first time, normal processing (1) (S24 in FIG. 2) is performed and the second and subsequent times are continuously generated. Performs normal processing (2) (S25 in FIG. 2), sets the level to 3 as the dead time for processing, and sets the level to 3 when the number of occurrences is the first time, and issues an abnormal alarm to stop the processing by issuing an abnormal alarm ( 1) (S26 in FIG. 2) is performed, and if the number of occurrences is the second or later, an abnormal stop such as no processing is performed.

  Referring to FIG. 3, a threshold value for each level with respect to a delay time used for determining a deadline level is defined for each event. For example, when a delay time of 0 milliseconds (msec) to within 10 msec is defined as level 1, it is defined as 10 msec at the level 1 threshold position of the corresponding event in the threshold table 31 for level determination, and within 11 to 20 msec. Is defined as level 2, it is defined as 20 msec at the level 2 threshold position of the event in the level determination threshold table. In addition, if the maximum level X is greater than 1000 msec, it is treated as all definitions, and if there is no level 2 and continues with level 1 and level 3, the position of the corresponding level 2 defines the same value as level 1, etc. At the time, the lower level is used for the determination.

  Referring to FIG. 4, an event execution process name corresponding to each level corresponding to the event is defined in a matrix table similar to the level determination threshold table 31 (76, 82), and obtained in the previous level determination. By updating the counter at the same position in the position and continuation occurrence count table 41 (77), it is possible to store the number of level continuation occurrences at the same level in the corresponding event.

  Referring to FIG. 6, in order to divide the processing according to the number of occurrences for each event and each level, the first case (X = 1) (X is the number of occurrences), the second and later (X> 1), the 20th and later An event corresponding to the event processing corresponding to the continuous occurrence count matrix table (event execution processing matrix table) 61 (51) for each of the continuous occurrence count determination formulas 62 corresponding to the number of occurrences, such as in the case of (X> 20). An execution processing function label 63 is defined.

  Referring to FIG. 10, an event notification with an event notification delay time added is performed at the time of event notification from the task control unit 103 to the task 101 side, and the measurement processing (S102 in FIG. 10) is performed in the measurement mode on the task 101 side. The number of occurrences of the corresponding event, the maximum delay time, the minimum delay time, and the average delay time are measured from the start of measurement according to the event notification delay time notified in this way, and recorded in the level determination measurement table 91.

  Referring to FIG. 7, in the event execution preparation process for task 21 (S71 in FIG. 7), the deadline level of the corresponding event is used for level determination from the event notification delay time added at the time of event notification from task control unit 27. Obtained by the threshold value table 76 (31, 82) (determining the matrix position) (S72 in FIG. 7), the corresponding event in the event execution process matrix table 78 (51, 61), the process corresponding to the obtained level and the number of occurrences Execute.

  As a result, if the notification delay time from the occurrence of the event (S15 in FIG. 1) is within the threshold value 1 <level 1>, normal processing (S23 in FIG. 2), greater than the threshold value 1 and within the threshold value 2 < If level 2> and the number of occurrences of level 2 is the first time, normal normal processing (1) (S24 in FIG. 2), normal normal processing (2) (S25 in FIG. 2), threshold 2 If it is larger and within threshold value 3 <level 3>, it is possible to separate the processing from the abnormal processing (1) (S26 in FIG. 2).

  Referring to FIG. 8, by giving a trigger from the external tool / other device 86, the measurement module 84 adjacent to the task control unit 81 measures the delay time generated for each event, and the measurement result is shown in FIG. The level determination measurement table 91 (FIG. 9) records each measurement pattern and enables output to the external tool / other device 86.

  An appropriate deadline threshold value is set according to the measurement result, and the level determination threshold value table 31 (82) is updated. That is, the rewriting module 83 can update the deadline threshold table (level determination threshold table) 82 (31) from the external tool / other device 86 via the external communication interface. Thereby, for example, the contents of the threshold level determination table 31 of the terminal can be updated by remote control from a server connected via a network.

  In the above embodiment, the delay time included in the event notification 28 and the number of occurrences of each level of the deadline are notified to the external tool or other device 86, so that the event processing in consideration of the delay time from the occurrence of the event and the number of occurrences In addition, the CPU load status can be grasped in terms of debugging function. In addition, it is possible to calculate and select an appropriate CPU speed performance from the delay time trend and statistics included in the event notification, and to examine optimization and maximization of the real-time OS.

As described above, according to the present embodiment, the following effects can be obtained.
The first effect is that the event execution delay time to the task side is recognized, and the normal normal processing can be finely assembled every time the deadline abnormality occurs. The reason is, for example, reprocessing (retry processing) in normal normal processing 1 when deadline level 2 occurs for the first time, processing interruption in normal processing 2 after the second time, and abnormal processing 1 when deadline level 2 occurs for the first time. A process that determines that it cannot be recovered due to a congested state or a semi-runaway state, and notifies that it cannot be processed outside (such as another device). The processing can be separated. In addition, when the level is high, the software itself has a runaway detection (watchdog timer / timeout) function, and it is possible to know which event has occurred and how many times the state has continued. Because.

  The second effect is that the event execution delay time in various states can be measured. The reason is that, from the statistics of the delay time of each event, an appropriate process can be constructed, and an appropriate threshold value can be predicted when the process is changed or when a hardware performance change occurs. In addition, it is possible to select the CPU speed performance at the time of initial hardware examination, and further, it is possible to examine optimization and maximum speed of the real-time OS 12.

  It should be noted that the configuration and operation of the above-described embodiment are examples, and it goes without saying that they can be changed as appropriate without departing from the spirit of the present invention.

It is a figure showing the delay until task event processing execution on real time OS by a time scale. FIG. 10 is a flow diagram in which the task side notifies the task event notification delay time of the present invention, and the task side determines the level of the delay time and branches to processing according to the level. It is a data block diagram of the threshold value table for level determination shown for every event of this invention. It is a data structure figure of the matrix table which counts the frequency | count of occurrence shown for each event and each level determination threshold value of this invention. It is a data structure figure of the event execution process matrix table shown for every event and each level determination threshold value of this invention. It is a data structure figure of the event execution process matrix table shown for every detailed level determination threshold value of the event of this invention. It is a flowchart which shows the event execution preparation process of this invention. It is a block diagram of each functional block which performs real time OS and task delay time measurement and rewriting in the present invention. It is a data structure figure of the measurement table which stores a measurement result for every event and each measurement pattern of the present invention. It is a processing flowchart for measuring the task event notification delay time of the present invention.

Explanation of symbols

11 Task 12 Real-time OS
13, 14, 15 Occurrence of events 1, 2, 3 16 Event notification delay time (T3)
17 Event notification to task 18 Event processing on task side 21 Task 27 Task control section 28 Event notification (event contents and delay time information)
31 level determination threshold table 41 continuous occurrence count table 51 level continuous occurrence frequency matrix table (event execution processing matrix table)
61 Matrix table of event continuation occurrence for each event and each level (event execution processing matrix table)
62 Continuous occurrence count judgment formula 63 Event execution processing function label 76 Level determination threshold table 77 Continuous generation count table 78 Event execution processing matrix table 81 Task control unit 82 Level determination threshold table 83 Rewrite module 84 Measurement module 85 External communication interface 86 External tool or other device 91 Level determination measurement table 101 Task 102 Measurement processing unit 103 Task control unit 104 Event notification (event contents and delay time information)

Claims (7)

Task control including a real-time OS that realizes interrupt processing in real-time control, an input / output interface function with peripheral devices, and the like, and a plurality of tasks that execute processing of events detected by the real-time OS on the real-time OS A device,
Measuring means for measuring the delay time notified to each task under load,
Measurement result storage means for storing the measurement result by the measurement means for each event;
Output means for outputting the measurement result to an external device;
Updating means for setting a deadline threshold based on the measurement result and updating a threshold table for level determination;
The task determines the level of the deadline of the delay time based on the threshold table for level determination based on the delay time from the occurrence of the event notified from the real-time OS. A task control device comprising: event processing means for processing the event by selecting and executing a processing program according to the number of occurrences. The real-time OS includes task control means for issuing an event notification to any of the tasks that process the event when the occurrence of the event is detected,
The event processing means of the task includes a threshold table for level determination that determines a level of a deadline of the delay time based on a delay time from the occurrence of the event attached to the event notification, and a level determination threshold table for each level. The task according to claim 1, further comprising: a continuation occurrence count table that stores the number of continuation occurrences, and an event execution processing matrix table that selects a processing program according to the level and the number of occurrences of the level. Control device. An external communication interface for controlling communication with an external tool or an external device;
The task control device according to claim 1 or 2, wherein the threshold table for level determination is updated from the external tool or the external device via the external communication interface. The level determination threshold table has a configuration in which the event numbers are arranged in the row direction and the deadline levels are arranged in the column direction, and each level corresponding to the delay time is set at the intersection of each row and column. The event execution processing matrix table has a configuration in which the event numbers are arranged in the row direction and the deadline levels are arranged in the column direction, and at the intersection of each row and column. The task control device according to claim 2, wherein a module name of a processing program that executes event processing at the level of the event number is defined for each occurrence number. The event processing means receives the event notification from the task control means, and when any of the tasks for executing the event processing of the event number attached to the event notification is activated, the task is Refer to a threshold table for level determination to determine the level of the deadline of the delay time of the event number, and then the task refers to the event execution processing matrix table and the event number of the event A module name corresponding to a level and the number of occurrences is selected, control is passed to a processing program having the module name, and the event is numbered to be processed. Item 5. The task control device according to any one of Items 1 to 4. Task control including a real-time OS that realizes interrupt processing in real-time control, an input / output interface function with peripheral devices, and the like, and a plurality of tasks that execute processing of events detected by the real-time OS on the real-time OS A method for task control in a device, comprising:
A measurement step for measuring the delay time notified to each task under load,
A measurement result storage step for storing the measurement result in the measurement step for each event;
An output step of outputting the measurement result to an external device;
An update step for setting a deadline threshold based on the measurement result and updating a threshold table for level determination;
The task determines the level of the deadline of the delay time based on the threshold table for level determination based on the delay time from the occurrence of the event notified from the real-time OS. A task control method comprising: an event processing step for processing the event by selecting and executing a processing program according to the number of occurrences. Task control including a real-time OS that realizes interrupt processing in real-time control, an input / output interface function with peripheral devices, and the like, and a plurality of tasks that execute processing of events detected by the real-time OS on the real-time OS A method for task control in a device, comprising:
A measurement step for measuring the delay time notified to each task under load,
A measurement result storage step for storing the measurement result in the measurement step for each event;
An output step of outputting the measurement result to an external device;
An update step for setting a deadline threshold based on the measurement result and updating a threshold table for level determination;
The task determines the level of the deadline of the delay time based on the threshold table for level determination based on the delay time from the occurrence of the event notified from the real-time OS. A task control method comprising: an event processing step for processing the event by selecting and executing a processing program according to the number of occurrences.

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