linux-master/kernel/fork.c

1396  * This changes mm's executable file (shown as symlink /proc/[pid]/exe).
1437  * This changes mm's executable file (shown as symlink /proc/[pid]/exe).
1962 init_task_pid(struct task_struct *task, enum pid_type type, struct pid *pid)
1965 		task->thread_pid = pid;
1967 		task->signal->pids[type] = pid;
1994  * @pid:   the struct pid for which to create a pidfd
1998  * Allocate a new file that stashes @pid and reserve a new pidfd number in the
2001  * The helper doesn't perform checks on @pid which makes it useful for pidfds
2002  * created via CLONE_PIDFD where @pid has no task attached when the pidfd and
2020 static int __pidfd_prepare(struct pid *pid, unsigned int flags, struct file **ret)
2029 	pidfd_file = pidfs_alloc_file(pid, flags | O_RDWR);
2045  * @pid:   the struct pid for which to create a pidfd
2049  * Allocate a new file that stashes @pid and reserve a new pidfd number in the
2052  * The helper verifies that @pid is still in use, without PIDFD_THREAD the
2053  * task identified by @pid must be a thread-group leader.
2070 int pidfd_prepare(struct pid *pid, unsigned int flags, struct file **ret)
2074 	if (!pid || !pid_has_task(pid, thread ? PIDTYPE_PID : PIDTYPE_TGID))
2077 	return __pidfd_prepare(pid, flags, ret);
2135 					struct pid *pid,
2183 	 * If the new process will be in a different pid or user namespace
2405 	if (pid != &init_struct_pid) {
2406 		pid = alloc_pid(p->nsproxy->pid_ns_for_children, args->set_tid,
2408 		if (IS_ERR(pid)) {
2409 			retval = PTR_ERR(pid);
2422 		/* Note that no task has been attached to @pid yet. */
2423 		retval = __pidfd_prepare(pid, flags, &pidfile);
2456 	p->pid = pid_nr(pid);
2462 		p->tgid = p->pid;
2542 	/* Don't start children in a dying pid namespace */
2543 	if (unlikely(!(ns_of_pid(pid)->pid_allocated & PIDNS_ADDING))) {
2563 	if (likely(p->pid)) {
2566 		init_task_pid(p, PIDTYPE_PID, pid);
2568 			init_task_pid(p, PIDTYPE_TGID, pid);
2572 			if (is_child_reaper(pid)) {
2573 				ns_of_pid(pid)->child_reaper = p;
2636 	if (pid != &init_struct_pid)
2637 		free_pid(pid);
2760 	struct pid *pid;
2809 	pid = get_task_pid(p, PIDTYPE_PID);
2810 	nr = pid_vnr(pid);
2832 		ptrace_event_pid(trace, pid);
2836 			ptrace_event_pid(PTRACE_EVENT_VFORK_DONE, pid);
2839 	put_pid(pid);