A Framework for Fixed Priority Periodic Scheduling Synthesis from Synchronous Data-Flow Graphs.

Synchronous data-flow graphs (SDF) are widely used in the design of concurrent real-time digital signal processing applications on multiprocessor system-on-chip. The increasing complexity of these hardware platforms advocates the use of real-time operating systems and fixed-priority scheduling to manage applications and resources. This trend calls for new methods to synthesize and implement actors in SDF graphs as real-time tasks with computed scheduling parameters (periods, priorities, processor mapping, etc.). This article presents a framework supporting scheduling synthesis, scheduling simulation, and code generation of these graphs. The scheduling synthesis maps each actor to a periodic real-time task and computes the appropriate buffer sizes and scheduling parameters. The results are verified by a scheduling simulator and instantiated by a code generator targeting the RTEMS (Real-Time Executive for Multiprocessor Systems) operating system. Experiments are conducted to evaluate the framework's performance and scalability as well as the overhead induced by the code generator.