Design And Implementation Of Real-Time Embedded Linux

With the rapid development of computer technology, communication technology and consumer electronic technology, real-time embedded system has been widely used. There are a lot of demands for real-time embedded operating system in fields of scientific research, engineering design, military technology, commerce entertainment etc. The purpose of my work is to design and realize a real-time embedded operating system.After introducing some relevant concepts, this thesis analyzes and researches Linux operating system, and makes it satisfy the requirement of real-time system and embedded system. On the aspect of real-time operating system, Linux has real-time task mechanism, but has not reached the hard real- time request. The thesis points out the key factors that influence real-time capacity by analyzing Linux schedule time and policy. There are a lot of improvement schemes to Linux real-time performance at present. Through analysis and comparison, I choose RT-Linux to carry on the theoretical research and analysis, and make the test of real-time performance and obtain a better test results. I has designed and realized three parts including system booting, minimizing kernel and minimizing file system on the aspect of embedded operating system. Connecting with system booting, this thesis introduces network booting and NFS file system. Connecting with kernel cutting, using modularized programming and loadable kernel module mechanism of Linux, I give some rules that decide what module will be compiled in the kernel. Connecting with file system cutting, ELF object file, dynamic and static link, standard C library and BusyBox concept have been used. Finally in my thesis, an embedded Firewall application based on the real-time embedded Linux has been complemented.