57 static long __wait_for_common(struct completion *x, long (*action)(long), long timeout, int state)  in __wait_for_common()  argument
63         while (!x->done && timeout > 0)  in __wait_for_common()
72             timeout = action(timeout);  in __wait_for_common()
76             return timeout; // 仍然没有complete, 但是被其他进程唤醒  in __wait_for_common()
84     return timeout ? timeout : 1; // 这里linux返回1，不知道为啥  in __wait_for_common()
106 long wait_for_completion_timeout(struct completion *x, long timeout)  in wait_for_completion_timeout()  argument
108     BUG_ON(timeout < 0);  in wait_for_completion_timeout()
110     timeout = __wait_for_common(x, &schedule_timeout_ms, timeout, PROC_UNINTERRUPTIBLE);  in wait_for_completion_timeout()
112     return timeout;  in wait_for_completion_timeout()
134 long wait_for_completion_interruptible_timeout(struct completion *x, long timeout)  in wait_for_completion_interruptible_timeout()  argument
136     BUG_ON(timeout < 0);  in wait_for_completion_interruptible_timeout()
139     timeout = __wait_for_common(x, &schedule_timeout_ms, timeout, PROC_INTERRUPTIBLE);  in wait_for_completion_interruptible_timeout()
141     return timeout;  in wait_for_completion_interruptible_timeout()