Research On Parallel Dynamic Binary Translation’s Lock-free Queue On Godson Platform

In recent years, the mainstream of the desktop and server software are developed for x86, but the godson is based on the MIPS. Therefore, It has a great importance to make the existing x86software compatible with MIPS architecture. Binary translation is an important way to make godson CPU compatible with x86software. QEMU is an important full-system emulator on godson platform. It can help windows XP running on godson, although the performance need to be improve.After CPU frequency reached2GHZ, with increased efficiency and bring performance improvement are increasingly limited, in order to ensure that Moore’s law continue to be valid, multi-core processors has become a trend. However, The existing emulator is serial and can only use a single core of host machine. It’s time to make full-system emulation parallelly. This will can greatly improve the machine’s performance and finally win a market.It has become a key point to study that how can we make Godson parallelly emulate the x86platform. Now parallel QEMU is under researching, PQEMU HQEMU, COREMU are all based on QEMU and parallelized on different aspect,but these parallel QEMU didn’t support godson platform.This paper mainly analyzes the QEMU, the SMP emulation of QEMU and the existing parallel QEMU. This paper make QEMU parallelly by emulatie the SMP machine parallely, the SMP core’s emulation logic are packaging into threads, OS schedule these threads running on host cores, this can make QEMU parallelly. The parallelization method needs to solve two key problems: atomic instruction translation problem and SMP machines interrupt simulation problems.Our team has put forward an atomic instruction translation scheme based on GCC built-in atomic operation function, but I found that there’re some problem in this scheme. One is that the expansion of the simple instruction translation is more than complex instruction, the other is that the scheme can olny solve some unaligned memory access not all. This paper proposes a new way,11/sc instructions are directly used to emulate x86atomic instruction, besides it can complete to solve the problem of unaligned atoms instruction.This article use the real-time signal and FIFO queue to implement the interrupt simulation of SMP machines.In order to ensure the efficiency of interrupt simulation, it is necessary to use unlocked technology.In this paper, according to the characteristics of11/sc, and the characteristics of lock-free queue in the interrupt simulation, I proposes a lock-free queue algorithm to avoid the ABA problem, which is more effective. I finally make QEMU parallelly run on godson3A platform and make full use of the godson’s multi core resources.