Mixed scheduling method of embedded real-time operating system

Abstract

The invention relates to a mixed scheduling method of an embedded real-time operating system. The method comprises the steps of pre-task scheduling resource allocation and task scheduling, wherein the task scheduling comprises the following steps: enabling a task to be ready in an event-trigger or time-trigger mode; looking for a priority decision table based on a ready list and a ready group to obtain the current ready highest task priority; and when the ready task of the highest priority is a collaborative task, directly running the collaborative task, removing the positions of the collaborative task in the ready list and the ready group after the completion of the collaborative task, and executing the previous step again. By treating ISR as the task, allocating priority along with other tasks, simultaneously combining the time-trigger and event-trigger framework and adopting the mixed scheduling mode of preemptive and collaborative tasks, the invention obtains a scheduling method which has the advantages of high predictability and reliability and high real-time response capability. The scheduling method can make full use of the system resources and effectively control the system overhead.

Description

technical field [0001] The invention relates to the technical field of design and implementation of an embedded operating system, and more specifically relates to a hybrid scheduling method of an embedded real-time operating system. Background technique [0002] With the rapid development of computer technology and the wide application of Internet technology, embedded system (Embedded System) is playing an increasingly important role. It is widely used in manufacturing industry, process control, communication, instrument, meter, automobile, ship , aerospace, military equipment, consumer products, etc. Embedded system is defined as application-centric, computer-based, software and hardware can be tailored to meet the strict requirements of the application system for function, reliability, cost, volume, power consumption, etc. Specialized computer system. [0003] Just because the application fields of embedded systems are expanding day by day, the functional requirements are...

AI Technical Summary

Problems solved by technology

[0012] Although the TTC scheduler (time-triggered cooperative scheduling) proposed by Michael J. Pont can effectively reduce task jitter in embedded systems, has high predictability and is simple to implement, but the real-time response of this scheduling method to external events The ability is relatively weak, and the scheduling method is not as flexible as preemptive scheduling, and the utilization rate of resources is relatively low

[0013] The real-time response capability of MicroC / OS II using the preemptive scheduling method is relatively ideal, but it cannot accurately execute a specific task within a specific time, and the time certainty is poor. Frequent context switching makes the system overhead larger and can be The predictability is relatively low, and the event-triggered preemptive scheduler is not as reliable as the time-triggered cooperative scheduler

Images