JP6890074B2 - Electronic control device - Google Patents

Description

The present invention relates to an electronic control device mounted on a vehicle.

An electronic control device mounted on a vehicle such as an automobile electronically controls a device to be controlled such as an actuator by sequentially executing a plurality of tasks according to a predetermined rule. At the design and development stage of an electronic control device, it is necessary to measure the processing load of a processor such as a CPU (Central Processing Unit) and verify, for example, whether the controlled device can be appropriately electronically controlled. In order to measure the processing load of the processor, as described in Japanese Patent Application Laid-Open No. 2003-15888 (Patent Document 1), the task execution time obtained by subtracting the execution start time from the execution end time of a specific task exceeds the threshold value. A technique for determining whether or not it is present has been proposed.

Japanese Patent Application Laid-Open No. 2003-15888

By the way, at the design and development stage of an electronic control device, when it is desired to measure the processing load for a part of a plurality of tasks for electronically controlling a controlled device, for example, verifying the processing load of a task that provides a specific function. There is. However, the technique described in Patent Document 1 can measure only the processing load of a specific task, and is inflexible in the verification of the electronic control device.

Therefore, an object of the present invention is to provide an electronic control device capable of preferentially measuring the processing load of a processor for a part of a plurality of tasks.

Therefore, the electronic control device in which the processor sequentially executes a plurality of tasks according to a predetermined rule measures the processing load of the processor as an idle task for each of the plurality of tasks, or is a normal task other than the idle task. It has a first setting mechanism for setting whether to measure the processing load of the processor. Then, when the processor executes each task set as a normal task by the first setting mechanism, the time required for executing the task is individually measured as a processing load. Further, when the processor executes the task set as the idle task by the first setting mechanism, the processor measures the integrated value of the time required for executing the task at the predetermined time interval as the processing load.

According to the present invention, in the electronic control device, the load of the processor can be preferentially measured for a part of a plurality of tasks.

It is a schematic diagram which shows an example of an electronic control device. It is explanatory drawing which shows an example of the data stored in a non-volatile memory. It is a block diagram which shows an example of the function built into the operating system. It is explanatory drawing which shows an example of the task executed by an electronic control device. It is explanatory drawing which shows an example of the configuration which defines a task. It is explanatory drawing which shows the other example of the configuration which defines a task. It is explanatory drawing of the method of measuring the processing load of a task.

Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the attached drawings.
FIG. 1 shows an example of an electronic control device 100 mounted on a vehicle such as an automobile.

The electronic control device 100 includes a microcomputer 120 having a CPU 120A, a ROM (Read Only Memory) 120B, a RAM (Random Access Memory) 120C, a timer 120D, an input / output circuit 120E, a communication circuit 120F, and a bus 120G. Here, the CPU 120A is given as an example of a processor.

The CPU 120A sequentially executes a plurality of tasks constituting the application program according to a predetermined rule, and determines, for example, the operation amount of the actuator according to the output from various sensors and outputs the operation amount. The ROM 120B is an example of a non-volatile memory capable of holding data even when the power supply is cut off, and includes, for example, a flash ROM, an EEPROM (Electrically Erasable Programmable ROM), and the like. The RAM 120C is an example of a volatile memory in which data is lost when the power is cut off, and includes, for example, a DRAM (Dynamic RAM), a SRAM (Static RAM), and the like. The timer 120D provides a timekeeping function such as outputting a pulse at predetermined time intervals and outputting an elapsed time from a reference point. The input / output circuit 120E provides an input / output function for an analog signal or a digital signal. The communication circuit 120F is communicably connected to a function of communicably connecting to another electronic control device and an external device 200 for verifying the function of the electronic control device 100 via, for example, CAN (Controller Area Network). Provide the function to do. The bus 120G connects the CPU 120A, ROM 120B, RAM 120C, timer 120D, input / output circuit 120E, and communication circuit 120F so as to be able to communicate with each other.

The external device 200 includes a personal computer having a CPU, ROM, RAM, timer, storage, input / output circuit, and communication circuit, and is detachably connected to the communication circuit 120F of the electronic control device 100 via, for example, a CAN cable 300. Will be done. Further, in the storage of the external device 200, a user program 400 for verifying the function of the electronic control device 100 is stored. Since the user program is not a main part of the present embodiment, its description will be omitted.

As shown in FIG. 2, the ROM 120B of the microcomputer 120 stores an operating system (OS) 420, an application program 440, control data 460, and a configuration 480.

The operating system 420 is located between the application program 440 and the hardware, provides a standard interface to the application program 440, and efficiently manages various resources such as the hardware. The application program 440 is a program for electronically controlling a controlled device such as an actuator, and is created by a user. The control data 460 is data such as constants used by the application program 440 and is created by the user. As will be described in detail later, the configuration 480 measures the processing load of the CPU 120A as an idle task for a plurality of tasks constituting the application program 440, or the processing load of the CPU 120A as a normal task other than the idle task. This is data for arbitrarily and individually setting whether to measure.

The configuration 480 can be rewritten by the external device 200 connected to the electronic control device 100. Further, the configuration 480 is not limited to the ROM 120B, and may be transmitted from the external device 200 and expanded to the RAM 120C. Here, the configuration 480 is given as an example of the first setting mechanism.

Further, the idle task is a task having the lowest priority, and is executed when a task having a higher priority is not executed. Therefore, when the processing load of the CPU 120A is high, the idle task may not be executed.

As shown in FIG. 3, the operating system 420 incorporates a task measurement service unit 424 in addition to the general dispatcher 422. Here, the task measurement service unit 424 is given as an example of a function of measuring the processing load.

The dispatcher 422 allocates a plurality of tasks 500 constituting the application program 440 according to their contents and uses. Further, the dispatcher 422 includes a task management unit 422A that controls and manages the execution of the task 500. The task management unit 422A analyzes the content and usage of the task 500, measures the processing load for each task 500, and measures the measurement cycle start signal that defines the measurement time (predetermined time interval) that serves as a reference for measuring the processing load of the CPU 120A. The task measurement start signal for starting the task and the task measurement end signal for ending the measurement of the processing load for each task 500 are transmitted to the task measurement service unit 424. An identifier (task ID) that makes it possible to identify the task 500 to be measured is attached to the task measurement start signal and the task measurement end signal.

The task measurement service unit 424 includes a higher-level task state management unit 424A, a plurality of lower-level task state management units 424B, and an idle task measurement unit 424C. Here, the task 500 also includes an idle task that has the lowest priority and is executed when a task having a higher priority than this is not executed.

When the upper task state management unit 424A receives the task measurement start signal, the upper task state management unit 424A transmits a measurement start signal for starting the measurement of the processing load to the lower task state management unit 424B associated with the task 500 specified by the task ID, and also transmits the measurement start signal. A measurement interruption signal is transmitted to the lower task status management unit 424B associated with the idle task. When the upper task state management unit 424A receives the task measurement end signal, the upper task state management unit 424A transmits the measurement end signal to the lower task state management unit 424B associated with the task 500 specified by the task ID, and is associated with the idle task. The measurement restart signal is output to the lower task status management unit 424B.

Upon receiving the measurement start signal, the subordinate task state management unit 424B associated with the task other than the idle task stores the execution start time of the task 500 specified by the task ID by using the timer 120D of the microcomputer 120. .. When the lower task state management unit 424B receives the measurement end signal, the lower task state management unit 424B uses the timer 120D of the microcomputer 120 to store the execution end time of the task 500 specified by the task ID. Then, the lower task state management unit 424B calculates the execution time of the task 500 by subtracting the execution start time from the execution end time of the task 500. At this time, the subordinate task state management unit 424B temporarily suspends the execution of the task 500 by executing the task 500 having a higher priority than the task 500 specified by the task ID, as will be described in detail later. In that case, the actual execution time is calculated by subtracting the interruption time from the execution time calculated as described above.

When the lower task state management unit 424B associated with the idle task receives the measurement restart signal, the lower task state management unit 424B transmits an idle time integration start signal to the idle task measurement unit 424C. Further, when the lower task state management unit 424B receives the measurement interruption signal, the lower task state management unit 424B transmits an idle time integration end signal to the idle task measurement unit 424C.

The idle task measurement unit 424C uses the timer 120D of the microcomputer 120 to measure the execution start time and the execution end time of the idle task, and subtracts the execution start time from the execution end time to execute the idle task. Calculate the time. Further, the idle task measurement unit 424C calculates an integrated value in which the execution times of the idle tasks calculated as described above are sequentially integrated from the time when the idle time integration start signal is received until the idle time integration end signal is received. To do. Further, when the idle task measurement unit 424C receives the measurement cycle start signal, the idle task measurement unit 424C clears (reset) the integrated value.

Here, an example of a plurality of tasks 500 constituting the application program 440 will be described. Since the task 500 described below is merely an example, it should not be understood that the actual task has such a configuration.

As shown in FIG. 4, the task 500 includes a 1 ms task executed every 1 ms, a 2 ms_0 task and a 2 ms_1 task executed every 2 ms, and a 5 ms_0 task to a 5 ms_4 task executed every 5 ms as scheduled tasks. Includes 10ms_0-10ms_9 tasks, which are performed every 10ms. Further, in addition to the idle task, the task 500 includes interrupt tasks xxxTask, yyTask, and zzzTask in which interrupts are generated irregularly due to an event. Then, when the offsets 0 to 9 at 1 ms intervals, which represent the execution timing of the task 500, are reached, a plurality of tasks associated with the offsets are appropriately executed.

As shown in FIG. 5, the configuration 480 stored in the ROM 120B measures the processing load as an "idle" indicating that the processing load is measured as an idle task for each task and as a normal task other than the idle task. It is configured so that the "load" indicating that can be set arbitrarily. The configuration 480 is not limited to the configuration shown in FIG. 5, and may be set to be “idle” or “load” by, for example, a flag associated with each task. Here, the flag is given as an example of the first setting mechanism.

In the configuration 480 of FIG. 5, the scheduled task and the interrupt task executed every 1 ms, 2 ms, 5 ms, and 10 ms are set to “load”, and the idle task is set to “idle”. In this way, the scheduled task and the interrupt task are preferentially measured for the processing load, and the processing load of the CPU 120A can be reduced as compared with the case where all the tasks are the measurement targets.

Further, when it is desired to measure only a part of a plurality of tasks, for example, a task related to SPI (Serial Peripheral Interface) communication, the processing load is set to "load" as shown in FIG. Then set the other tasks to "idle". In the configuration 480 of FIG. 6, the scheduled task 5ms_0 task and the interrupt task xxxTask are targeted for preferentially measuring the processing load, and in addition to reducing the processing load of the CPU 120A, there is no extra measurement result. Therefore, the man-hours for design and development can be reduced. Note that the configuration 480 is not limited to the one shown in FIGS. 5 and 6, and when measuring the load, at least a part of a plurality of tasks constituting the application program 440 may be set to "load".

Next, with reference to FIG. 7, a specific method for measuring the processing load of a plurality of tasks constituting the application program 440 will be described.

As a premise of the following description, in the configuration 480 stored in the ROM 120B, it is assumed that the task ID_0, the task ID_1, the task ID_2, and the task ID_3 are set to "load" and the task ID_4 is set to "idle". .. Further, as shown in FIG. 7, the priority of each task is assumed to be sequentially increased in the order of task ID_4, task ID_0, task ID_1, task ID_2, and task ID_3. Further, the electronic control device 100 shall execute each task in the following order. For convenience of explanation, "task ID_4" set to "idle" will be referred to as "idle task ID_4".

1. 1. Start of load measurement of task ID_0 The task management unit 422A transmits a task measurement start signal indicating that the load measurement of task ID_0 is started to the task measurement service unit 424. Upon receiving the task measurement start signal, the task measurement service unit 424 interrupts the processing load measurement of the idle task ID_4 and calculates and integrates the execution time of the idle task ID_4 (xxx). Further, the task measurement service unit 424 stores the execution start time t1 of the task ID_0.

2. End of load measurement of task ID_0 The task management unit 422A transmits a task measurement end signal indicating that the load measurement of task ID_0 is completed to the task measurement service unit 424. Upon receiving the task measurement end signal, the task measurement service unit 424 subtracts the execution start time t1 from the execution end time t2 of the task ID_0, and sets this as the execution time (t2-t1) of the task ID_0. At this time, since the task having a higher priority than this is not executed during the execution of the task ID_0, the task measurement service unit 424 sets the execution time (t2-t1) of the task ID_0 as the processing load. Further, the task measurement service unit 424 restarts the processing load measurement of the idle task ID_4.

3. 3. Start of load measurement of task ID_3 The task management unit 422A transmits a task measurement start signal indicating that the load measurement of task ID_3 is started to the task measurement service unit 424. Upon receiving the task measurement start signal, the task measurement service unit 424 interrupts the processing load measurement of the idle task ID_4 and stores the execution start time t3 of the task ID_3. Further, the task measurement service unit 424 obtains the execution time (t3-t2) of the idle task ID_4 by subtracting the execution end time t2 of the task ID_0 from the execution start time t3 of the task ID_3, and sets the execution time of the idle task ID_4 as the cumulative execution time. Accumulate (xxx+ (t3-t2)). Further, since the task measurement service unit 424 executes the task ID_3, which is an example of a predetermined scheduled task, which defines the measurement time as a reference for measuring the processing load of the task, the execution integrated time of the idle task ID_4 is cleared (reset). ).

4. End of load measurement of task ID_3 The task management unit 422A transmits a task measurement end signal indicating that the load measurement of task ID_3 is completed to the task measurement service unit 424. Upon receiving the task measurement end signal, the task measurement service unit 424 subtracts the execution start time t3 from the execution end time t4 of the task ID_3, and sets this as the execution time (t4-t3) of the task ID_3. At this time, since the task ID_3 is the task with the highest priority, the task measurement service unit 424 sets the execution time (t4-t3) of the task ID_3 as the processing load. Further, the task measurement service unit 424 restarts the processing load measurement of the idle task ID_4.

5. Start of load measurement of task ID_0 The task management unit 422A transmits a task measurement start signal indicating that the load measurement of task ID_0 is started to the task measurement service unit 424. Upon receiving the task measurement start signal, the task measurement service unit 424 interrupts the processing load measurement of the idle task ID_4 and stores the execution start time t5 of the task ID_0. Further, the task measurement service unit 424 obtains the execution time (t5-t4) of the idle task ID_4 by subtracting the execution end time t4 of the task ID_3 from the execution start time t5 of the task ID_0, and sets the execution time of the idle task ID_4 as the cumulative execution time. Accumulate (0+ (t5-t4)).

6. Start of load measurement of task ID_1 The task management unit 422A transmits a task measurement start signal indicating that the load measurement of task ID_1 is started to the task measurement service unit 424. Upon receiving the task measurement start signal, the task measurement service unit 424 executes the task ID_1 having a higher priority than the task ID_0 being executed, so that the processing load measurement of the task ID_0 is interrupted and the execution start time t6 of the task ID_1 is set. Remember.

7. Start of load measurement of task ID _2 The task management unit 422A transmits a task measurement start signal indicating that the load measurement of task ID _2 is to be started to the task measurement service unit 424. Upon receiving the task measurement start signal, the task measurement service unit 424 executes the task ID_2 having a higher priority than the task ID_1 being executed, so that the processing load measurement of the task ID_1 is interrupted and the execution start time t7 of the task ID_2 is set. Remember.

8. End of load measurement of task ID _2 The task management unit 422A transmits a task measurement end signal indicating that the load measurement of task ID _2 is to be completed to the task measurement service unit 424. Upon receiving the task measurement end signal, the task measurement service unit 424 subtracts the execution start time t7 from the execution end time t8 of the task ID _2, and sets this as the execution time (t8-t7) of the task ID _2. At this time, since the task having a higher priority than the task ID _2 was not executed, the task measurement service unit 424 uses the execution time (t8-t7) of the task ID _2 as the processing load. In addition, the task measurement service unit 424 resumes the suspended processing load measurement of the task ID_1.

9. End of load measurement of task ID_1 The task management unit 422A transmits a task measurement end signal indicating that the load measurement of task ID_1 is completed to the task measurement service unit 424. Upon receiving the task measurement end signal, the task measurement service unit 424 subtracts the execution start time t6 from the execution end time t9 of the task ID_1, and sets this as the execution time (t9-t6) of the task ID_1. At this time, since the task ID_2 having a high priority is executed during the execution of the task ID_1 and the execution of the task ID_1 is temporarily interrupted, the task measurement service unit 424 starts from the execution time (t9-t6) of the task ID_1. The execution time (t8-t7) of the task ID_1 is subtracted, and this is used as the processing load of the task ID_1 ((t9-t6)-(t8-t7)). In addition, the task measurement service unit 424 resumes the suspended processing load measurement of the task ID_0.

10. End of load measurement of task ID_0 The task management unit 422A transmits a task measurement end signal indicating that the load measurement of task ID_0 is completed to the task measurement service unit 424. Upon receiving the task measurement end signal, the task measurement service unit 424 subtracts the execution start time t5 from the execution end time t10 of the task ID_0, and sets this as the execution time (t10-t5) of the task ID_0. At this time, the task ID_1 and the task ID_2, which have high priority, are executed during the execution of the task ID_0, and the execution of the task ID_0 is temporarily interrupted. Therefore, the task measurement service unit 424 determines the execution time of the task ID_0 (t10-). The execution time (t9-t6) of task ID_1 and task ID_2 is subtracted from t5), and this is taken as the processing load of task ID_0 ((t10-t5)-(t9-t6)). Further, the task measurement service unit 424 restarts the processing load measurement of the idle task ID_4.

11. Start of load measurement of task ID_3 The task management unit 422A transmits a task measurement start signal indicating that the load measurement of task ID_3 is started to the task measurement service unit 424. Upon receiving the task measurement start signal, the task measurement service unit 424 interrupts the processing load measurement of the idle task ID_4 and stores the execution start time t11 of the task ID_3. Further, the task measurement service unit 424 obtains the execution time (t11-t10) of the idle task ID_4 by subtracting the execution end time t10 of the task ID_0 from the execution start time t11 of the task ID_3, and sets the execution time of the idle task ID_4 as the cumulative execution time. Accumulate ((t5-t4) + (t11-10)). Further, since the task measurement service unit 424 executes ID_3, which is an example of a predetermined scheduled task that defines the measurement time as a reference for measuring the processing load of the task, the execution integrated time of the idle task ID_4 is cleared.

12. End of load measurement of task ID_3 The task management unit 422A transmits a task measurement end signal indicating that the load measurement of task ID_3 is completed to the task measurement service unit 424. Upon receiving the task measurement end signal, the task measurement service unit 424 subtracts the execution start time t11 from the execution end time t12 of the task ID_3, and sets this as the execution time (t12-t11) of the task ID_3. At this time, since the task ID_3 is the task with the highest priority, the task measurement service unit 424 uses the execution time (t12-t11) of the task ID_3 as the processing load. Further, the task measurement service unit 424 restarts the processing load measurement of the idle task ID_4.

Therefore, since the processing load of the CPU 120A is preferentially measured for the task set as "load" in the configuration 480, the load is measured for a part of a plurality of tasks for electronically controlling the controlled device. Can be done. Therefore, flexibility can be imparted with respect to the verification of the electronic control device 100.

Also, when measuring the processing load of a certain task, even if at least one task with a higher priority is executed, the time during which the processing was interrupted is subtracted from the execution time of the certain task. It is possible to improve the measurement accuracy of the processing load of the task. In short, when the CPU 120A is measuring the processing load of a task set to "load", if another task having a higher priority than that task is executed, the CPU 120A is set to "load" during execution of the other task. Suspends the measurement of the time required to execute the task.

Furthermore, for the processing load measurement of tasks set to "idle", the processing load is the integrated value obtained by integrating only the time when the task was actually executed, with the execution interval of the scheduled task with the highest priority as the measurement time. Therefore, the measurement accuracy of the processing load of the task can be improved.

Since the task measurement service unit 424 that provides such a function is incorporated in the operating system 420, a user who uses the task measurement service unit 424 only needs to create an interface to the task measurement service unit 424. Therefore, the electronic control device 100 can easily measure the processing load of a plurality of tasks constituting the application program 440 even after the vehicle equipped with the electronic control device 100 is shipped to the market, not limited to the manufacturing factory or the like. is there.

Further, in the electronic control device 100, for example, it may be possible to collectively set whether or not to measure the processing load of the CPU 120A by the configuration 480. Then, when the electronic control device 100 is set to measure the processing load of the CPU 120A, the electronic control device 100 may measure the time required to execute the task. In this way, after the vehicle equipped with the electronic control device 100 is shipped to the market, the processing load of the CPU 120A is not measured, so that the electronic control of the original controlled device can be avoided from being hindered. Can be done. Here, the configuration 480 that collectively sets whether or not to measure the processing load of the CPU 120A is given as an example of a second setting mechanism that sets whether or not to measure the processing load of the processor.

In addition, when measuring the processing load of a task set to "idle", instead of accumulating the execution time of the task, the interruption time during which the execution of the task is interrupted is integrated, and the interruption time is calculated from the measured time. You may try to subtract.

With respect to the above-described embodiment, a new embodiment can be created by arbitrarily combining a part of the technical idea or arbitrarily rearranging a part thereof. Therefore, it should be understood that the present invention is not limited to the contents described in the above-described embodiment, but includes technical ideas that can be easily recalled by those skilled in the art.

100 Electronic control device 120A CPU (processor)
420 Operating system 424 Task measurement service department (function to measure processing load)
480 configuration (first setting mechanism)
500 tasks

Claims (6)

An electronic control device in which a processor sequentially executes a plurality of tasks according to a predetermined rule.
For each of the plurality of tasks, a first setting mechanism for setting whether to measure the processing load of the processor as an idle task or to measure the processing load of the processor as a normal task other than the idle task is provided. Have and
When the processor executes each task set for the normal task by the first setting mechanism, the time required for executing the task is individually measured as a processing load, and the first setting mechanism individually measures the time required for executing the task. When the task set to the idle task is executed, the integrated value of the time required to execute the task at a predetermined time interval is measured as a processing load.
Electronic control device. When the processor is measuring the processing load of the task set for the normal task, if another task having a higher priority than the task is executed, the normal task is being executed during the execution of the other task. It is configured to interrupt the measurement of the time required to execute the task set in.
The electronic control device according to claim 1. The first setting mechanism is a configuration that defines the plurality of tasks, or a flag associated with each of the plurality of tasks.
The electronic control device according to claim 1 or 2. A second setting mechanism for setting whether or not to measure the processing load of the processor is provided.
The processor is configured to measure the time required to execute the task when it is set to measure the processing load by the second setting mechanism.
The electronic control device according to any one of claims 1 to 3. The function of measuring the processing load is built into the operating system.
The electronic control device according to any one of claims 1 to 4. The predetermined time interval is defined as a time interval for executing a predetermined scheduled task.
The electronic control device according to any one of claims 1 to 5.

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