Linux Kernel Development——列出系统中所有的进程

1. 在内核模块中列出所有的进程：

从init_task开始遍历内核链表，输出所有进程

#include <linux/module.h>
#include <linux/list.h>
#include <linux/init.h>
#include <linux/sched.h>

MODULE_LICENSE("Dual BSD/GPL");

static int test_init(void)
{
        struct task_struct *task, *p;
        struct list_head *pos;
        int count=0;

        printk(KERN_ALERT "test module init\n");

        task=&init_task;
        list_for_each(pos, &task->tasks)
        {
                p=list_entry(pos, struct task_struct, tasks);
                count++;
                printk(KERN_ALERT "%s[%d]\n", p->comm, p->pid);
        }
        printk(KERN_ALERT "Total %d tasks\n", count);

        return 0;
}

static void test_exit(void)
{
        printk(KERN_ALERT "test module exit!\n");
}

module_init(test_init);
module_exit(test_exit);

Makefile

ifneq ($(KERNELRELEASE),)
        obj-m := test.o
else
        KDIR := /lib/modules/$(shell uname -r)/build

PWD := $(shell pwd)

default:
    $(MAKE) -C $(KDIR) M=$(PWD) modules
endif

2. 使用Systemtap输出所有进程：

//process_list.stp

%{  
#include <linux/list.h>
#include <linux/sched.h>
%}

function process_list ()
%{  
    struct task_struct *p;
    struct list_head *_p,*_n;

    for_each_process(p){
        _stp_printf("%-15s (%-5d)\n",p->comm,p->pid);
    }
%}

probe begin
{   
    process_list();
    exit()
}

运行方法

# stap -g process_list.stp 
init            (1    )
kthreadd        (2    )
migration/0     (3    )
ksoftirqd/0     (4    )
migration/0     (5    )
watchdog/0      (6    )
migration/1     (7    )
migration/1     (8    )
ksoftirqd/1     (9    )
watchdog/1      (10   )
events/0        (11   )
events/1        (12   )
cpuset          (13   )
khelper         (14   )
netns           (15   )
....

3. 使用Systemtap打印进程uts命名空间信息

 //namespace_uts.stp
 %{
     #include<linux/list.h>

     #include<linux/sched.h>

     #include <linux/nsproxy.h>

     #include<linux/utsname.h>
 %}

function process_list ()
 %{
    struct task_struct *p;
    struct list_head *_p,*_n;
    struct uts_namespace *uts;
    struct new_utsname *utsname;

    for_each_process(p){
        uts=p->nsproxy->uts_ns;
        utsname=&(uts->name);
        _stp_printf("%-15s(%-5d) %-24s %-16s\n", p->comm,p->pid,utsname->release, utsname->sysname);
     }
 %}

probe begin
 {
    process_list();
    exit()
 }

# stap -g namespace_uts.stp 
init           (1    ) 2.6.32-220.el6.x86_64    Linux           
kthreadd       (2    ) 2.6.32-220.el6.x86_64    Linux           
migration/0    (3    ) 2.6.32-220.el6.x86_64    Linux           
ksoftirqd/0    (4    ) 2.6.32-220.el6.x86_64    Linux           
migration/0    (5    ) 2.6.32-220.el6.x86_64    Linux           
watchdog/0     (6    ) 2.6.32-220.el6.x86_64    Linux           
migration/1    (7    ) 2.6.32-220.el6.x86_64    Linux           
migration/1    (8    ) 2.6.32-220.el6.x86_64    Linux 
....

本文参考：

http://blog.csdn.net/lzuzhp06/article/details/6933525

《Linux Kernel Development》