Networks-on-Chips (NoCs) are considered to be the paradigm of choice for on-chip communication and are today widely adopted in many-core systems. Many existing routing solutions make use of virtual channels (VCs) to avoid deadlocks while offering enough routing flexibility to avoid faulty and congested areas in a NoC. However, most of the current solutions rely on an overly restrictive, static partitioning of VCs, which results in an underutilization of their throughput enhancement capabilities. To overcome the limitations of such approaches, we introduce a new sufficient condition of deadlock-freedom that greatly relaxes the restrictions imposed by the classic VC-based deadlock-avoidance methods. The strength of our condition lies in the fact that it is imposed on packets at runtime and does not require any partitioning of virtual channels, which makes it possible to fully exploit them to reduce packet blocking and boost performance. Based on this condition, we present a generic, topology-agnostic routing algorithm design methodology that can be used to construct highly flexible routing algorithms in only a few steps. Several examples are presented to showcase the usefulness of our approach for the construction of fault-tolerant routing algorithms, as well as the enhancement and the proof of existing routing algorithms. The implementation of all the required mechanisms in hardware is also described in detail, thereby demonstrating its feasibility in an on-chip environment.

中文翻译：

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片上网络中高性能容错路由的无死锁动态充分条件

片上网络 (NoC) 被认为是片上通信的首选范例，如今在众核系统中被广泛采用。许多现有的路由解决方案使用虚拟通道 (VC) 来避免死锁，同时提供足够的路由灵活性以避免 NoC 中的错误和拥塞区域。然而，当前的大多数解决方案依赖于过度限制性的 VC 静态分区，这导致其吞吐量增强功能未得到充分利用。为了克服这种方法的局限性，我们引入了一个新的无死锁充分条件，它大大放宽了经典的基于 VC 的死锁避免方法所施加的限制。我们条件的优势在于它是在运行时强加给数据包的，不需要对虚拟通道进行任何分区，这使得可以充分利用它们来减少数据包阻塞并提高性能。基于这种情况，我们提出了一种通用的、拓扑不可知的路由算法设计方法，只需几个步骤即可构建高度灵活的路由算法。提供了几个例子来展示我们的方法在构建容错路由算法方面的有用性，以及现有路由算法的增强和证明。还详细描述了硬件中所有必需机制的实现，从而证明了其在片上环境中的可行性。拓扑不可知的路由算法设计方法，只需几个步骤即可构建高度灵活的路由算法。提供了几个例子来展示我们的方法在构建容错路由算法方面的有用性，以及现有路由算法的增强和证明。还详细描述了硬件中所有必需机制的实现，从而证明了其在片上环境中的可行性。拓扑不可知的路由算法设计方法，只需几个步骤即可构建高度灵活的路由算法。提供了几个例子来展示我们的方法在构建容错路由算法方面的有用性，以及现有路由算法的增强和证明。还详细描述了硬件中所有必需机制的实现，从而证明了其在片上环境中的可行性。