The Design And Implementation Of Embedded Multi-core Processor Communication Methods

With the continuous advancement of processor manufacturing process as well as the exposed limitation of single-core processors, multi-core processors has become the inevitable outcome of the practical application needs and technological development. With emergence of multi-core processors, some problems were brought. One of the hot issue is communication technology between multi-core processors in computer architecture today. On the one hand, the major manufacturers have made different communication standard of multi-core processor implementations, and how to choose communications solutions for different embedded processors environment is very important. On the other hand, the existing multi-core communication is often related to hardware platforms, and there are the existence of poor portability.Aiming at these problems, on the basis of specifications MCAPI standard, this paper designs and implements a multi-core communication library with the features of simple, feasible and high portability. The multi-core communication library is mainly for inter-core communication between multi-core chips, compared to other existing mature multi-core communication libraries such as MPI, etc., it has lower communication latency, memory footprint and more lightweight.In the design and implementation process, this paper first proposed standard OpenMCAPI existing poor transplant, graft platform-specific issues, and then analysis message interrupt mechanism MSGRs in library implementation; Subsequently, this paper proposes a set of functions API which separate from the actual hardware platform constraints, and using IPC as the underlying communication mechanism. The multi-core communication library architecture can be divided into the application layer, the core layer and the porting layer, layered architecture design allows library code more clear, and easy to maintain. In addition, aiming at homogeneous multi-core processor platform and heterogeneous multi-core processor platform, message queues, shared memory binding domain sockets and other mechanisms as the underlying means of communication is encapsulated in multi-core communication library code, so that achieving separation between upper layer interface and the underlying API, and achieving a structured and modular code.This paper makes functional and performance tests for multi-core communications library which is based on the realization of open source OpenMCAPI multi-core communications library. For dual-core X86 PC platform and four ARM cores KeystoneII platform, this paper makes time delay and data transfer rate tests for realization of connectionless message communication and connection-oriented packet communication. Finally, we make compare with existing standards OpenMCAPI and other APIs implementations, and experimental results show that the multi-core communication library implemented in this article can not only communicate between each core, but also have certain advantages in terms of performance than the standard OpenMCAPI. This set of API functions implemented in this article provides a convenient function call interface for multi-core communication software developers, and there is an important application value.