for_each_process-是否还会遍历线程和进程? [英] for_each_process - Does it iterate over the threads and the processes as well?

问题描述

我想迭代内核中的所有任务(线程和进程)，并使用for_each_process宏打印tid/pid和名称:

I would like to iterate all the tasks in the kernel (threads and processes) and print tid/pid and name using for_each_process macro:

#define for_each_process(p) \
    for (p = &init_task ; (p = next_task(p)) != &init_task ; )

如何区分线程和进程?

How can I distinguish between thread and process?

所以我将这样打印:

 if (p->real_parent->pid == NULL)
      printk("PROCESS: name: %s pid: %d \n",p->comm,p->pid);
 else
      printk("THREAD: name: %s tid: %d \n",p->comm,p->pid);

推荐答案

您需要以下宏:

/*
 * Careful: do_each_thread/while_each_thread is a double loop so
 *          'break' will not work as expected - use goto instead.
 */
#define do_each_thread(g, t) \
        for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do

#define while_each_thread(g, t) \
        while ((t = next_thread(t)) != g)

像这样使用它们:

        rcu_read_lock();
        do_each_thread(g, t) {
            //...
        } while_each_thread(g, t);

        rcu_read_unlock();

这篇关于for_each_process-是否还会遍历线程和进程?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！