Design And Implementation Of A Prototype Of RTOS For SMP Processor

With the development of semiconductor technology,multi-core processor chips have already had the advantages of high performance and low price.The processors of SMP architecture are also widely used in people's lives and industry.RTOS is a class of operating system that aims to ensure real-time performance for embedded applications.In recent years,many research institutes and operating system vendors have developed RTOS that support SMP processors to better utilize the advantages of multi-core processors.The author of this thesis researched the typical RTOS for SMP,and found some shortages of it.Some open source RTOS lacks good real-time performance in SMP processor task scheduling strategy.Some RTOS support for non-polling multi-resource wait mode is not perfect,which may affect the real-time performance of task scheduling in strong real-time environments.Another part of the RTOS lacks memory management mechanisms to reduce external fragmentation,which may result in non-available memory allocation when the task frequently performs memory application and release operations.Based on the above situation,this thesis designs an RTOS prototype for SMP processor named AntOS attemptting to improve some function of the typical RTOS:SMP processor task scheduling strategy,multiple resources waiting strategy,memory management.First of all,AntOS's task scheduling strategy is for SMP processors,ensuring that the highest priority N(N is the number of processor cores)tasks is running.This strategy can enable each core of the processor to perform task scheduling,thereby improving the real-time degradation bottleneck caused by the frequent task scheduling of the main processor core in the master-slave design.Secondly,AntOS designed a non-polling multi-resources waiting strategy so that real-time tasks can wait on multiple resources.When the task is awakened,all ready resources can be obtained without polling all waiting resource states.Finally,AntOS has designed a memory management mechanism that can reduce external fragmentation.When real-time tasks perform frequent memory operations,external memory fragmentation can be reduced.The author implemented AntOS on the iMX6Q development board equipped with an ARM Cortex-A9 SMP processor.AntOS was tested to meet functional requirements requirements,real-time performance is better than Linux in the same hardware environment.This thesis has carried on the new exploration to the RTOS facing SMP processor,the research result has the high practical significance.