Research And Implementation Of Real-Time Scheduling Strategy Based On Linux Kernel

The real-time operating systems are widly used in every fields, and paid more and more attention. The researchers of the embedded real-time operation system focus on the Linux because of its openness of original code, its designs of loadable kernel module and high flexibility of kernel size. However, as the idea of designers, by means of time divided multi-tasks, limits the application of Linux in real-time, extending of real-time approaches shall be applied to satisfy the requirements of the embedded systems to the real-time capability.In this dissertation, the related conception of process scheduling for Linux 2.6.11 edition was introduced, the process scheduling algorithm and strategy were emphasized, which included their disadvantages and rectification. With regard to disadvantages which the real-time scheduling strategy in Linux is the singular, a process scheduling mechanism, which oriented application and was able to support various scheduling algorithm, was put forward in this dissertation.What were done could be listed as follows:Firstly, the basic idea and the framework of the process scheduling mechanism, which support various scheduling algorithm through separating the shceduling into choosing scheduler and specific scheduling, was put forward. The scheduling mechanism expanded the scheduling system application.Secondly, based on the analysis of several popular real-time linux schemes, RTAI was imported as a platform for application-oriented scheduling. Through this platform, the data structure and function interface for scheduling mechanism were designed, also RM and EDF scheduler were implimented to support RM and EDF scheduling algorithms.Thirdly, experimental platform was built to test interrupt latency and context-switching time for standard linux and RTAI. With analysis of the experimental result, the validity of application-oriented scheduling mechanism was affirmed. The application-oriented scheduling mechanism presented in this dissertation improves the performance of standard linux kenerl and gives a solution for various real-time enviornment, which is profound for the application in real-time linux embedding research.