【摘要】 无线传感器网络等物联网系统通常具有资源高度受限且与物理世界耦合的特性,这使得该类系统部署后的设备通常难以调试。因此,在部署前对整个系统进行充分的测试与评价显得尤为重要。传统基于串口的网络化测试手段具有较大的侵入性,且无法对资源受限设备的运行情况进行详细的跟踪。文中对硬件辅助追踪技术在物联网测试评价中的应用进行了研究,设计并实现了一种硬件辅助追踪测试平台——HATBED(Hardware Assisted Tracing Testbed)。HATBED由控制器、观察者以及被测目标组成,可以提供网络级远程调试、灵活的软件追踪以及非侵入式软件分析等主要功能,并在不依赖操作系统与应用的前提下,实现对系统的非侵入式追踪与分析。实验中,首先使用裸机与FreeRTOS操作系统下的标准例程,从功耗开销、时间精度以及代码覆盖率3个方面对HATBED进行了基准性能的测试;然后,以物联网RIOT-OS代码库程序为例,通过HATBED实现了ping6的高精度时间特性分析,及其底层gnrc协议栈UDP通信过程函数覆盖与基本块覆盖的评估。实例分析表明,借助硬件辅助追踪技术,HATBED可以对资源受限的物联网系统开展更加高效、充分的测试与评价。更多还原

【Abstract】 Internet of Things systems,such as wireless sensor networks,usually have the characteristics of the high restriction of the resources and coupling with the physical world,which makes it difficult to debug the equipment after deployed.Therefore,it is especially important to thoroughly test and profile the systems before deploying to the real world.Due to the intrusiveness,traditional debugging methods based on the serial port are incompetent for detailed tracing on resource-constrained devices.This paper studies the application of hardware assisted tracing technology in the embedded network sensor systems’ test and evaluation.Then,it designs and realizes a Hardware Assisted Tracing testBed(HATBED).HATBED consists of a controller,observers,and targets.It can provide three services,network-wide remote debugging,flexible software tracing and non-invasive software profiling.HATBED can support non-intrusive tracing and profiling without relying on operating systems and applications.In the experiment,this paper benchmarks time and power consumption,time accuracy,and code coverage under bare-metal and FreeRTOS.Then,it tests the RIOT-OS examples and completes the ping6 command high time accuracy feature profiling and UDP communication function coverage and basic block coverage.With the help of hardware assisted tracing technology,HATBED can eva-luate the resource-constrained Internet of Things systems more efficiently and adequately.更多还原