关键词: 延迟锁, 自旋锁, 实时Linux, 响应时间

Abstract: A new method called delayed lock is proposed，to reduce the latency of real-time task in real-time kernel.The basic rule of this method is that a non-real-time task entering a critical section is allowed only if the operation does not disturb the future execution of the real-time application.To execute this rule，this paper introduced the concepts of timer interrupt prediction and lock hold time.In addition，the paper also designed and implemented a new urgent timer for this technique，and the prototype on Linux 2.6.Experimental results show that the worst-case Linux’s latency to real-time process is reduced to 23%，at the expense of slowdown of the non-real-time process by 20%.

Key words: delayed lock, spin-lock, real-time Linux, latency