Analysis And Implementation Of Program Worst-Case Execution Time On Multi-Core Processor

The Analysis of the Worst-Case Execution Time for program aims to obtain the estimation of worst-case execution time by using analytical techniques before execution.The WCET estimation of program are used as input criteria for task scheduling in real-time operating systems.The static analysis,which includes program flow analysis,processor architecture behavior analysis and WCET calculation,can model the complex processor structure and calculate the reliable estimation value of program WCET,is usually adopted to guarantee safe result in real-time systems.With the development of multi-core processor technology,multi-core processors have been applied to embedded devices so on.The WCET analysis of the task on the multi-core processor platform has become a topic for WCET researchers.How to abstract the model of shared cache,pipeline and branch predictors from multi-core processor is a difficult task in static WCET analysis.Given the above background,we first research the implementation of static WCET analysis technology based on the literature and open source WCET analysis tool.Secondly,we analyzes the ARM multi-core processor and abstract the micro-architecture characteristics of ARM multi-core processor,including cache,pipeline,branch predictor etc,which is used in the design of processor architecture behavior analysis.In the program flow design scheme,we design a porting scheme of ARM instruction and propose a analysis process based on the ARM instruction set,including ELF file analysis,basic block recognition and generation of program control flow analysis.In the micro-architecture behavior analysis design scheme,we adopt and modify the scheme proposed by Chronos,which combine the multi-level instruction cache,shared bus,branch predictor into pipeline.In the WCET calculation scheme,we use the Implicit Path Enumeration Technique method.Then,based on the design scheme,we implement a WCET analysis tool based on ARM multi-core processor platform.Finally,we test the WCET analysis tool.In the experiments,we used the benchmarks provided by the University of Malardalens.In order to verify the WCET estimation of benchmarks is safe,we take a comparative experiment on FPGA development board Zedboard,which equipped with ARM Cortex A9 dual-core processor.The experimental results show that the WCET estimation of benchmark obtained by our WCET analysis tool is safe.