在内核模式下计算进程的子进程数和sibiling数

时间:2016-04-10 22:28:01

标签: c linux kernel system-calls

我对计算一个过程中的孩子和兄弟姐妹的数量感到有点困惑。我有一个进程信息的结构,如下所示:

struct process_info {
    long pid; /* Process ID */
    char name[/* Some size. */]; /* Program name of process */
    long state; /* Current process state */
    long uid; /* User ID of process owner */
    long nvcsw; /* # voluntary context switches */
    long nivcsw; /* # involuntary context switches */
    long num_children; /* # children process has */
    long num_siblings; /* # sibling process has */
};

我有一个函数可以填充并返回上面结构中的过程信息:

struct process_info get_process_info(struct task_struct* this_task) {
    struct process_info res;
    int temp_num_children = 0;
    int temp_num_sibling = 0;
    struct list_head* traverse_ptr;

    res.pid = this_task->pid;
    memcpy(res.name, this_task->comm, /* The size of the string declared before the struct above. */);
    res.state = this_task->state;
    res.uid = this_task->cred->uid.val;
    res.nvcsw = this_task->nvcsw;
    res.nivcsw = this_task->nivcsw;


    list_for_each(traverse_ptr, &(this_task->children)) {
        ++temp_num_children;
    }


    list_for_each(traverse_ptr, &(this_task->sibling)) {
        ++temp_num_sibling;
    }
    res.num_children = temp_num_children;
    res.num_siblings = temp_num_sibling;

    return res;
}

填写除子和兄弟之外的所有信息非常简单,因为它们已经在struct task_list实例中。但是,我想使用list_for_each函数计算子项和兄弟的数量,但我不知道这是否是正确的方法。

1 个答案:

答案 0 :(得分:0)

struct task_struct的子节点和兄弟节点链接了所述任务的所有子节点和兄弟节点,所以是的,你正在做的是正确的。