背景

上篇博客写了如何在gem5的full system模式运行alpha的指令编译的程序，这篇博客讲述如何在gem5的full system模式运行x86指令集编译的程序，这两种方式非常类似。

首先需要安装gem5-stable，可以参考我前面的一篇博客：

http://blog.csdn.net/wyj7260/article/details/8267345

这篇文章介绍full system  in  x86。

安装过程：

下载full system需要的两个包：

首先在安装好gem5-stable之后，再到官网下载full system需要的包：

Full System Files : http://www.m5sim.org/dist/current/x86/x86-system.tar.bz2

Config files : http://www.m5sim.org/dist/current/x86/config-x86.tar.bz2

安装：记我的gem5-stable安装目录为$GEM

a)      ~/gem5-stable$  mkdir x86Dist

b)      将包x86-system.tar.bz2和config-x86.tar.bz2复制到x86Dist目录下

b) ~/gem5-stable$ cd x86Dist/

c) ~/gem5-stable/x86Dist$  tar -xvf x86-system.tar.bz2

把exceptKeyError:

path = [ '/dist/m5/system', '/n/poolfs/z/dist/m5/system

修改成

except KeyError:

path = [ '/dist/m5/system', ' /home/wyj2/gem5-stable/x86Dist' ]

运行(运行过程中遇到的error以及解决方法)

1、  首先编译gem5.opt

~/gem5-stable $ scons ./build/x86/gem5.opt

2、运行模拟的linux系统

~/gem5-stable$ ./build/X86/gem5.opt ./configs/example/fs.py

报错如下：

gem5 Simulator System. http://gem5.org

gem5 is copyrighted software; use the --copyright option for details.

gem5 compiled Jul 12 2013 21:30:39

gem5 started Jul 12 2013 21:33:06

gem5 executing on arch-node3

command line: ./build/X86/gem5.opt ./configs/example/fs.py

warning: add_child('terminal'): child 'terminal' already has parent

Global frequency set at 1000000000000 ticks per second

info: No kernel set for full system simulation. Assuming you know whatyou're doing if not SPARC ISA

0: rtc: Real-time clock setto Sun Jan  1 00:00:00 2012

panic: Error opening /home/wyj/gem5-stable/x86Dist/disks/x86root.img

@ cycle 0

[open:build/X86/dev/disk_image.cc, line 79]

Memory Usage: 225092 KBytes

Program aborted at cycle 0

Aborted (core dumped)

解决方法：

提示不能打开x86root.img，于是我查找x86root.img

命令：~/gem5-stable$ grep -r"x86root.img" ./

得到如下：

./configs/common/Benchmarks.py:            return env.get('LINUX_IMAGE',disk('x86root.img'))

如实修改Benchmarks.py, 把return env.get('LINUX_IMAGE',disk('x86root.img'))改成

return env.get('LINUX_IMAGE', disk('linux-x86.img'))

然后执行：

~/gem5-stable$ ./build/X86/gem5.opt ./configs/example/fs.py

gem5 Simulator System. http://gem5.org

gem5 is copyrighted software; use the --copyright option for details.

gem5 compiled Jul  2 201310:06:26

gem5 started Jul 13 2013 18:13:18

gem5 executing on jsi-desktop

command line: ./build/X86/gem5.opt ./configs/example/fs.py

warn: add_child('terminal'): child 'terminal' already has parent

Global frequency set at 1000000000000 ticks per second

info: No kernel set for full system simulation. Assuming you know whatyou're doing

0: rtc: Real-time clock setto Sun Jan  1 00:00:00 2012

panic: Error opening/home/wyj2/gem5-stable/x86Dist/disks/linux-bigswap2.img

@ cycle 0

[open:build/X86/dev/disk_image.cc, line 79]

Memory Usage: 177860 KBytes

Program aborted at cycle 0

Aborted

缺少linux-bigswap2.img文件，秩序要将alpha的full system下载的包Full System Files解压后的linux-bigswap2.img拷贝到目录/home/wyj2/gem5-stable/x86Dist/disks/就行。

（full system Files下载地址http://www.m5sim.org/dist/current/m5_system_2.0b3.tar.bz2解压也可得）

运行

~/gem5-stable$ ./build/X86/gem5.opt ./configs/example/fs.py

仍然报错

gem5 Simulator System.  http://gem5.org

gem5 is copyrighted software; use the --copyright option for details.

gem5 compiled Jul  2 201310:06:26

gem5 started Jul 13 2013 18:18:48

gem5 executing on jsi-desktop

command line: ./build/X86/gem5.opt ./configs/example/fs.py

warn: add_child('terminal'): child 'terminal' already has parent

Global frequency set at 1000000000000 ticks per second

info: No kernel set for full system simulation. Assuming you know whatyou're doing

0: rtc: Real-time clock setto Sun Jan  1 00:00:00 2012

Listening for com_1 connection on port 3456

warn: Reading current count from inactive timer.

0: system.remote_gdb.listener: listening for remote gdb #0 on port 7000

fatal: No kernel to load.@ cycle 0

[initState:build/X86/arch/x86/system.cc, line 118]

Memory Usage: 177868 KBytes

这是因为运行时需要制定kernel：

运行命令为：

./build/X86/gem5.opt ./configs/example/fs.py --kernel=x86_64-vmlinux-2.6.22.9.smp

注意：此处不用制定.smp文件的路径，只用文件名就行

剩下的mount文件到模拟的系统同上一篇关于alpha的full system

。

参考链接：

http://www.m5sim.org/Running_M5_in_Full-System_Mode

http://novel.ict.ac.cn/qguo/pdf/gem5.pdf

http://gem5.org/dist/tutorials/hipeac2012/gem5_hipeac.pdf

以及参考师兄的ppt