分类： LINUX
2008-04-23 00:56:30
1 解压缩linux内核及rtai源码
[root@haitao-desktop ~]# cd /usr/src
[root@haitao-desktop src]# tar jxvf linux-2.6.7.tar.bz2
[root@haitao-desktop src]# tar jxvf rtai-3.1.tar.bz2
2 针对linux-2.6.7打rtai-3.1补丁
[root@haitao-desktop
src]# cd linux-2.6.7
[root@haitao-desktop linux-2.6.7]# patch -p1 < ../rtai-3.1/rtai-core/arch/i386/patches/hal6-2.6.7.patch
patching file Documentation/adeos.txt
patching file Makefile
patching file adeos/Kconfig
patching file adeos/Makefile
patching file adeos/generic.c
patching file adeos/x86.c
patching file arch/i386/Kconfig
patching file arch/i386/kernel/Makefile
patching file arch/i386/kernel/adeos.c
patching file arch/i386/kernel/apic.c
patching file arch/i386/kernel/cpu/mcheck/p4.c
patching file arch/i386/kernel/entry.S
patching file arch/i386/kernel/i386_ksyms.c
patching file arch/i386/kernel/i8259.c
patching file arch/i386/kernel/io_apic.c
patching file arch/i386/kernel/irq.c
patching file arch/i386/kernel/nmi.c
patching file arch/i386/kernel/process.c
patching file arch/i386/kernel/signal.c
patching file arch/i386/kernel/smp.c
patching file arch/i386/kernel/smpboot.c
patching file arch/i386/kernel/time.c
patching file arch/i386/kernel/timers/timer_tsc.c
patching file arch/i386/kernel/traps.c
patching file arch/i386/mm/fault.c
patching file include/asm-i386/adeos.h
patching file include/asm-i386/io_apic.h
patching file include/asm-i386/mach-default/do_timer.h
patching file include/asm-i386/mach-default/irq_vectors.h
patching file include/asm-i386/mach-pc9800/do_timer.h
patching file include/asm-i386/mach-pc9800/irq_vectors.h
patching file include/asm-i386/mach-visws/do_timer.h
patching file include/asm-i386/mach-visws/irq_vectors.h
patching file include/asm-i386/smp.h
patching file include/asm-i386/system.h
patching file include/linux/adeos.h
patching file include/linux/init_task.h
patching file include/linux/preempt.h
patching file include/linux/sched.h
patching file init/main.c
patching file kernel/Makefile
patching file kernel/adeos.c
patching file kernel/exit.c
patching file kernel/fork.c
patching file kernel/panic.c
patching file kernel/printk.c
patching file kernel/sched.c
patching file kernel/signal.c
patching file kernel/sysctl.c
要分析x86系统上的RTAI实现，patch对于我们来说是最好的一个入口点了。
3、配置内核
[root@haitao-desktop linux-2.6.7]# cp /boot/config-2.6.9-22.EL .config
直接将rhas4发行版的config文件复制过来，这样省了我们不少的配置工作，后面就只要在此基础上进行少量的配置修改便可。
[root@haitao-desktop linux-2.6.7]# make menuconfig
Loadable module support
[*] Enable loadble module support
[*] Module unloading
[*] Forced module unloading
[ ] Module versioning support (EXPERIMENTAL)
[*] Automatic kernel module loading
Processor type and features
[*] Preemptible Kernel
[ ] Use register arguments (EXPERIMENTAL)
Device drivers -> Character devices
[M] Enable Real Time Clock Support
Adeos Support
<*> Adeos support (NEW)
Kernel hacking
[
] Compile the kernel with frame pointers
4、编译Linux内核
[root@haitao-desktop linux-2.6.7]# make bzImage
[root@haitao-desktop linux-2.6.7]# make modules
[root@haitao-desktop linux-2.6.7]# make modules_install
呵呵，以上几步工作可是最费时的，还是泡杯咖啡、打开音乐先享受一番了；当然，要是你有受虐倾向的话，强烈建议死死盯着显示屏，包你满意 : p
5、安装新编译的linux内核
[root@haitao-desktop linux-2.6.7]# make install
这一步可算是劳苦功高了，看看/boot目录下是不是一切都为我们准备好了，包括initrd-2.6.7-adeos.img、vmlinuz-2.6.7-adeos和System.map-2.6.7-adeos。而且，grub引导项也自动为我们添加了，当然对于引导项后面还要作一点小的修改。
[root@haitao-desktop
linux-2.6.7]# df -h
Filesystem 容量 已用 可用 已用% 挂载点
/dev/sda1 9.7G 5.3G 3.9G 58% /
none 125M 0 125M 0% /dev/shm
/dev/sda2
4.2G 160M 3.9G 4% /home
可知，/目录的挂载点是/dev/sda1，这在下面的引导项中root要用到。
[root@haitao-desktop linux-2.6.7]# vi /boot/grub/grub.conf
在make install之后生成了如下的引导项：
title Red Hat Enterprise Linux AS (2.6.7-adeos)
root (hd0,0)
kernel /boot/vmlinuz-2.6.7-adeos ro root=LABEL=/ rhgb quiet
initrd /boot/initrd-2.6.7-adeos.img
将其修改为：（区别在root处）
title Red Hat Enterprise Linux AS (2.6.7-adeos)
root (hd0,0)
kernel /boot/vmlinuz-2.6.7-adeos ro root=/dev/sda1
initrd /boot/initrd-2.6.7-adeos.img
6、重启以使用新编译内核
[root@haitao-desktop linux-2.6.7]# reboot
引导时，选择“Red Hat Enterprise Linux AS (2.6.7-adeos)”项，呵呵，激动人心的时刻到来了，千万不要panic了，没关系，即便出现了我们再尝试解决问题就是。然而结果是好的，顺利进入系统之后，运行如下命令：
[root@haitao-desktop ~]# uname –a
Linux haitao-desktop 2.6.7-adeos #1 Wed Apr 23 03:09:26 CST 2008 i686 athlon i386 GNU/Linux
可见现在已经是使用我们新编译的内核2.6.7-adeos，当然在VMware里日期时间有些问题，懒得管了，继续下面我们的RTAI编译安装吧！
7、配置RTAI
[root@haitao-desktop rtai-3.1]# make menuconfig
General
(/usr/src/linux-2.6.7) Linux Source tree
[*] Enable source compatibility mode
[*] Enable extended configuration mode
一定要记得，linux源码树位置一定是指向自己新编译的内核/usr/src/linux-2.6.7，其它的就使用缺省配置吧，以后确实要用到什么，再重新配置就可以。记得最后要保存对配置文件所做的修改。
8、编译RTAI
[root@haitao-desktop rtai-3.1]# make
9、安装RTAI
[root@haitao-desktop rtai-3.1]# make install
安装目录有make menuconfig中已经指定了，我们使用的是缺省的/usr/realtime目录。
10、测试RTAI
[root@haitao-desktop rtai-3.1]# cd /usr/realtime/testsuite/kern/latency
[root@haitao-desktop latency]# ./run
[root@haitao-desktop latency]# ls
display latency_rt.ko run
[root@haitao-desktop latency]# ./run
*
*
* Type ^C to stop this application.
*
*
## RTAI latency calibration tool ##
# period = 100000 (ns)
# avrgtime = 1 (s)
# check overall worst case
# do not use the FPU
# start the timer
# timer_mode is oneshot
2008/04/23 08:00:06 min: -4498 max: 15130864 average: 154531
2008/04/23 08:00:07 min: -4498 max: 15749943 average: 161019
2008/04/23 08:00:08 min: -4498 max: 15749943 average: 131757
2008/04/23 08:00:09 min: -4498 max: 15749943 average: 100065
2008/04/23 08:00:10 min: -4498 max: 15749943 average: 112296
2008/04/23 08:00:11 min: -4498 max: 15749943 average: 134921
2008/04/23 08:00:12 min: -4498 max: 15749943 average: 150379
2008/04/23 08:00:12 min: -4498 max: 15749943 average: 150379
梦寐以久的RTAI是不是就跑起来了，是时候站起身来活动活动了，在电脑前面呆久了可不好 : - )
