A Bounded Spin Lock Algorithm with Preemption

Predictable interprocessor synchronization and fast interrupt response are important for real-time systems constructed using asymmetric shared-memory multiprocessors. This paper points out the problem that existing spin lock algorithms cannot satisfy both requirements at the same time, and proposes a new algorithm to solve this problem. The algorithm, an extension of queueing spin locks modified to be preemptable for servicing interrupts, can give an upper bound on the time to acquire and release an interprocessor lock while achieving fast response to interrupt requests. The effectiveness of the algorithm is demonstrated through performance evaluation. 1 Introduction Requirements for large-scale and high performance real-time systems are increasing with the expansion of the application areas of embedded real-time systems. In particular, these requirements are rapidly increasing in the areas of large-scale control systems (industrial-plant control and aircraft control systems), and com..