Segment Streaming for the Three-Phase Execution Model: Design and Implementation
Segment Streaming for the Three-Phase Execution Model: Design and Implementation
复制标题
DOI：
10.1109/rtss46320.2019.00032
复制
发表时间：
2019-12
期刊：
影响因子：
--
通讯作者：
M. R. Soliman;G. Gracioli;Rohan Tabish;R. Pellizzoni;M. Caccamo
中科院分区：
文献类型：
--
作者：
M. R. Soliman;G. Gracioli;Rohan Tabish;R. Pellizzoni;M. Caccamo
使用三相执行模型（LOAD-ECECUTE-UNLOAD）调度任务可以有效地减少实时系统中共享资源的争论。由于系统和程序的约束，通常在多个间隔上进行分割和执行任务。几项工作表明，共同安排内存（卸载）和计算阶段可以通过隐藏内存传输时间来改善系统的计划性。但是，这仅限于不同任务的段，因此不允许背靠背执行相同任务的段。在本文中，我们提出了一个新的流式模型，以重叠相同任务段的内存和执行阶段。这是通过基于LLVM的编译器级工具以及实时操作系统（RTOS）API在基于LLVM的编译器级工具中实现的细分框架来完成的，以处理加载/卸载请求。内存阶段是通过将任务内容加载到ScratchPad内存（SPM）的DMA引擎处理的。我们在固定优先级分区方案下提供了对拟议模型的计划分析，并在最新一代多处理器系统中（MPSOC）对API的RTOS实现。
Scheduling tasks using the three-phase execution model (load-execute-unload) can effectively reduce the contention on shared resources in real-time systems. Due to system and program constraints, a task is generally segmented and executed over multiple intervals. Several works showed that co-scheduling memory (unload-load) and computation phases can improve the system schedulability by hiding the memory transfer time. However, this is limited to segments of different tasks and hence executing segments of the same task back-to-back is not allowed. In this paper, we propose a new streaming model to allow overlapping the memory and execution phases of segments of the same task. This is accomplished by a segmentation framework implemented within an LLVM-based compiler-level tool along with a Real-Time Operating System (RTOS) API to handle load/unload requests. Memory phases are processed by a DMA engine that loads/unloads the task content into ScratchPad Memory (SPM). We provide a schedulability analysis of the proposed model under fixed priority partitioned scheme and an RTOS implementation of the API on a latest-generation Multiprocessor System-on-Chip (MPSoC).