CSR: Small: A Comprehensive Framework for Real-Time Multiprocessor Synchronization

多核技术的出现推动了许多关于设计、部署和验证实时应用程序的多处理器实现方法的最新工作。 这些方法必须植根于有助于可预测系统设计的资源分配技术。 在这些技术的工作中，调度算法，分配处理器的时间，受到了最大的关注。 同步算法，协调对其他资源的访问，受到的关注要少得多。目前的国家的最先进的关于实时多处理器同步是简单的锁定协议可以支持，但没有太多。 这是一个严重的障碍，限制了实时应用程序向“多核就绪”版本的发展。 在此驱动下，本项目正在开发一套丰富的多处理器实时同步机制。 这些机制是由真实的应用需求所驱动的，正如AT T和诺斯罗普·格鲁曼公司的研究人员和工业界同事在联合工作中所提出的那样。 这种机制被设计用于几种系统模型，也是出于真实的需要。 这些包括模型，其中存在各种复杂性，如具有不同的关键任务，多个子系统，必须“隔离”彼此，异构硬件组件，动态任务行为等。在所有这些工作中，最佳同步协议的设计正在强调。 这些协议正在UNC开发的一个名为LITMUS^RT的开源实时Linux扩展中进行原型制作和评估。更广泛的影响将包括与行业同事继续进行联合研究，以及开发可供其他机构用于研究和教学目的的公开开源软件。

The advent of multicore technologies has fueled much recent work on methods for designing, deploying, and verifying multiprocessor implementations of real-time applications. Such methods must necessarily be rooted in resource allocation techniques that facilitate predictable system designs. In work on such techniques, scheduling algorithms, which allocate processor time, have received the greatest attention. Synchronization algorithms, which coordinate access to other resources, have received much less attention.The current state-of-the-art regarding real-time multiprocessor synchronization is that simple locking protocols can be supported, but not much else. This is a serious impediment that is limiting the evolution of real-time applications to "multicore-ready" versions. Driven by this, a rich set of multiprocessor real-time synchronization mechanisms is being developed in this project. These mechanisms are motivated by real application needs, as have arisen in joint work involving the investigators and industry colleagues at AT&T and Northrop Grumman. Such mechanisms are being designed for use within several system models, also motivated by real needs. These include models wherein various complexities exist, such as having tasks of differing criticalities, multiple subsystems that must be "isolated" from one another, heterogeneous hardware components, dynamic task behaviors, etc. In all of this work, the design of optimal synchronization protocols is being emphasized. These protocols are being prototyped and evaluated within a open-source UNC-produced real-time Linux extension called LITMUS^RT. Broader impacts will include continued joint research with industry colleagues, and the development of publicly-available open-source software that can be used by other institutions for research and teaching purposes.