On 02/02, Christian Brauner wrote: > > > TODO: change do_notify_pidfd() to use the keyed wakeups. > > How does the following appended patch look? No, no. I think we need a simpler patch. I was going to send it as 4/4, but I'd like to think more, _perhaps_ we can also discriminate the PIDFD_THREAD and non-PIDFD_THREAD waiters. I'll try to make the patch(es) tomorrow or at least provided more info. 3 notes for now: 1. we can't use wake_up_poll(), it passes nr_exclusive => 1 2. exit_notify() should not pass EPOLLHUP to wake_up, we do not want to wake up the { .events = POLLHUP } waiters. 3. we do not need to change __change_pid(). Well, _perhaps_ it can/should use __wake_up_pollfree(), but I need to check if fs/select.c use "autoremove" or not. > -static __poll_t pidfd_poll(struct file *file, struct poll_table_struct *pts) > +static __poll_t pidfd_poll(struct file *file, poll_table *wait) > { > struct pid *pid = file->private_data; > bool thread = file->f_flags & PIDFD_THREAD; > struct task_struct *task; > __poll_t poll_flags = 0; > > - poll_wait(file, &pid->wait_pidfd, pts); > + poll_wait(file, &pid->wait_pidfd, wait); This is correct but only cosemtic and has nothing to do with what we discuss? Oleg.