A Linux kernel with fixed interrupt latency for embedded real-time system

Abstract

This paper proposes a Linux 2.6./spl times/ hard real-time system on ARM MMU-less platform, and compares the performance of the new system to the original one. Traditionally, Linux is designed mainly for desktop and server applications, it focuses on the throughput and overall workloads. Therefore, it hardly satisfies the real-time embedded systems' requirements. In order to improve the real-time performance of the Linux system, this paper realizes the priority inheritance protocol in the kernel source, and rewrites the interruption service routings by a new method: kernel thread. The experiments show that this new scheme tremendously decreases the interrupt latency and the time needed to enter the critical sections for applications, which is a quite important feature required by real-time system.