Commit 6c67716d authored by Peter Hurley's avatar Peter Hurley Committed by Greg Kroah-Hartman
Browse files

n_tty: Only perform wakeups for waiters 



Only wakeup the _waiting_ reader, polls and/or writer(s).

Signed-off-by: default avatarPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent eafbe67f

drivers/tty/n_tty.c

+12 −6
Original line number Diff line number Diff line
@@ -274,6 +274,7 @@ static void n_tty_check_unthrottle(struct tty_struct *tty) 
			return;

		n_tty_set_room(tty);

		n_tty_write_wakeup(tty->link);

		if (waitqueue_active(&tty->link->write_wait))

			wake_up_interruptible_poll(&tty->link->write_wait, POLLOUT);

		return;

	}
@@ -349,6 +350,7 @@ static void n_tty_packet_mode_flush(struct tty_struct *tty) 
	spin_lock_irqsave(&tty->ctrl_lock, flags);

	if (tty->link->packet) {

		tty->ctrl_status |= TIOCPKT_FLUSHREAD;

		if (waitqueue_active(&tty->link->read_wait))

			wake_up_interruptible(&tty->link->read_wait);

	}

	spin_unlock_irqrestore(&tty->ctrl_lock, flags);
@@ -1155,6 +1157,7 @@ static void n_tty_receive_break(struct tty_struct *tty) 
		put_tty_queue('\0', ldata);

	}

	put_tty_queue('\0', ldata);

	if (waitqueue_active(&tty->read_wait))

		wake_up_interruptible(&tty->read_wait);

}
@@ -1213,6 +1216,7 @@ static void n_tty_receive_parity_error(struct tty_struct *tty, unsigned char c) 
		put_tty_queue('\0', ldata);

	else

		put_tty_queue(c, ldata);

	if (waitqueue_active(&tty->read_wait))

		wake_up_interruptible(&tty->read_wait);

}
@@ -1802,7 +1806,9 @@ static void n_tty_set_termios(struct tty_struct *tty, struct ktermios *old) 
		start_tty(tty);



	/* The termios change make the tty ready for I/O */

	if (waitqueue_active(&tty->write_wait))

		wake_up_interruptible(&tty->write_wait);

	if (waitqueue_active(&tty->read_wait))

		wake_up_interruptible(&tty->read_wait);

}