Messages in this thread Patch in this message | | | Date | Tue, 29 Apr 2008 14:26:11 +0100 | From | Alan Cox <> | Subject | [PATCH] tty: Add throttle/unthrottle helpers |
| |
Something Arjan suggested which allows us to clean up the code nicely
Signed-off-by: Alan Cox <alan@redhat.com>
diff -u --new-file --recursive --exclude-from /usr/src/exclude linux.vanilla-2.6.25-mm1/drivers/char/tty_ioctl.c linux-2.6.25-mm1/drivers/char/tty_ioctl.c --- linux.vanilla-2.6.25-mm1/drivers/char/tty_ioctl.c 2008-04-28 11:36:48.000000000 +0100 +++ linux-2.6.25-mm1/drivers/char/tty_ioctl.c 2008-04-14 14:27:41.000000000 +0100 @@ -67,6 +67,24 @@ EXPORT_SYMBOL(tty_driver_flush_buffer); +void tty_throttle(struct tty_struct *tty) +{ + /* check TTY_THROTTLED first so it indicates our state */ + if (!test_and_set_bit(TTY_THROTTLED, &tty->flags) && + tty->ops->throttle) + tty->ops->throttle(tty); +} + +EXPORT_SYMBOL(tty_throttle); + +void tty_unthrottle(struct tty_struct *tty) +{ + if (test_and_clear_bit(TTY_THROTTLED, &tty->flags) && + tty->ops->unthrottle) + tty->ops->unthrottle(tty); +} + +EXPORT_SYMBOL(tty_unthrottle); /** * tty_wait_until_sent - wait for I/O to finish diff -u --new-file --recursive --exclude-from /usr/src/exclude linux.vanilla-2.6.25-mm1/include/linux/tty_driver.h linux-2.6.25-mm1/include/linux/tty_driver.h --- linux.vanilla-2.6.25-mm1/include/linux/tty_driver.h 2008-04-28 11:36:52.000000000 +0100 +++ linux-2.6.25-mm1/include/linux/tty_driver.h 2008-04-14 14:27:30.000000000 +0100 @@ -83,10 +83,10 @@ * void (*set_termios)(struct tty_struct *tty, struct ktermios * old); * * This routine allows the tty driver to be notified when - * device's termios settings have changed. + * device's termios settings have changed. * * Optional: Called under the termios lock * * * void (*set_ldisc)(struct tty_struct *tty); * @@ -100,6 +100,8 @@ * This routine notifies the tty driver that input buffers for * the line discipline are close to full, and it should somehow * signal that no more characters should be sent to the tty. + * + * Optional: Always invoke via tty_throttle(); * * void (*unthrottle)(struct tty_struct * tty); * @@ -107,12 +109,14 @@ * that characters can now be sent to the tty without fear of * overrunning the input buffers of the line disciplines. * + * Optional: Always invoke via tty_unthrottle(); + * * void (*stop)(struct tty_struct *tty); * * This routine notifies the tty driver that it should stop * outputting characters to the tty device. * - * Optional: + * Optional: * * Note: Call stop_tty not this method. * @@ -141,7 +145,7 @@ * * If this routine is implemented, the high-level tty driver will * handle the following ioctls: TCSBRK, TCSBRKP, TIOCSBRK, - * TIOCCBRK. + * TIOCCBRK. * * Optional: Required for TCSBRK/BRKP/etc handling. * diff -u --new-file --recursive --exclude-from /usr/src/exclude linux.vanilla-2.6.25-mm1/include/linux/tty.h linux-2.6.25-mm1/include/linux/tty.h --- linux.vanilla-2.6.25-mm1/include/linux/tty.h 2008-04-28 11:36:52.000000000 +0100 +++ linux-2.6.25-mm1/include/linux/tty.h 2008-04-28 12:26:36.000000000 +0100 @@ -303,6 +321,8 @@ extern int tty_chars_in_buffer(struct tty_struct *tty); extern int tty_write_room(struct tty_struct *tty); extern void tty_driver_flush_buffer(struct tty_struct *tty); +extern void tty_throttle(struct tty_struct *tty); +extern void tty_unthrottle(struct tty_struct *tty); extern int is_current_pgrp_orphaned(void); extern struct pid *tty_get_pgrp(struct tty_struct *tty); diff -u --new-file --recursive --exclude-from /usr/src/exclude linux.vanilla-2.6.25-mm1/drivers/bluetooth/hci_ldisc.c linux-2.6.25-mm1/drivers/bluetooth/hci_ldisc.c --- linux.vanilla-2.6.25-mm1/drivers/bluetooth/hci_ldisc.c 2008-04-28 11:36:48.000000000 +0100 +++ linux-2.6.25-mm1/drivers/bluetooth/hci_ldisc.c 2008-04-28 11:43:39.000000000 +0100 @@ -370,9 +370,7 @@ hu->hdev->stat.byte_rx += count; spin_unlock(&hu->rx_lock); - if (test_and_clear_bit(TTY_THROTTLED, &tty->flags) && - tty->ops->unthrottle) - tty->ops->unthrottle(tty); + tty_unthrottle(tty); } static int hci_uart_register_dev(struct hci_uart *hu) diff -u --new-file --recursive --exclude-from /usr/src/exclude linux.vanilla-2.6.25-mm1/drivers/char/n_tty.c linux-2.6.25-mm1/drivers/char/n_tty.c --- linux.vanilla-2.6.25-mm1/drivers/char/n_tty.c 2008-04-28 11:36:48.000000000 +0100 +++ linux-2.6.25-mm1/drivers/char/n_tty.c 2008-04-14 14:26:29.000000000 +0100 @@ -147,10 +147,8 @@ static void check_unthrottle(struct tty_struct *tty) { - if (tty->count && - test_and_clear_bit(TTY_THROTTLED, &tty->flags) && - tty->ops->unthrottle) - tty->ops->unthrottle(tty); + if (tty->count) + tty_unthrottle(tty); } /** @@ -982,12 +980,8 @@ * mode. We don't want to throttle the driver if we're in * canonical mode and don't have a newline yet! */ - if (tty->receive_room < TTY_THRESHOLD_THROTTLE) { - /* check TTY_THROTTLED first so it indicates our state */ - if (!test_and_set_bit(TTY_THROTTLED, &tty->flags) && - tty->ops->throttle) - tty->ops->throttle(tty); - } + if (tty->receive_room < TTY_THRESHOLD_THROTTLE) + tty_throttle(tty); } int is_ignored(int sig) diff -u --new-file --recursive --exclude-from /usr/src/exclude linux.vanilla-2.6.25-mm1/drivers/net/hamradio/6pack.c linux-2.6.25-mm1/drivers/net/hamradio/6pack.c --- linux.vanilla-2.6.25-mm1/drivers/net/hamradio/6pack.c 2008-04-28 11:36:49.000000000 +0100 +++ linux-2.6.25-mm1/drivers/net/hamradio/6pack.c 2008-04-14 14:29:14.000000000 +0100 @@ -491,9 +491,7 @@ sixpack_decode(sp, buf, count1); sp_put(sp); - if (test_and_clear_bit(TTY_THROTTLED, &tty->flags) - && tty->ops->unthrottle) - tty->ops->unthrottle(tty); + tty_unthrottle(tty); } /* diff -u --new-file --recursive --exclude-from /usr/src/exclude linux.vanilla-2.6.25-mm1/drivers/net/hamradio/mkiss.c linux-2.6.25-mm1/drivers/net/hamradio/mkiss.c --- linux.vanilla-2.6.25-mm1/drivers/net/hamradio/mkiss.c 2008-04-28 11:36:49.000000000 +0100 +++ linux-2.6.25-mm1/drivers/net/hamradio/mkiss.c 2008-04-14 14:29:29.000000000 +0100 @@ -936,9 +936,7 @@ } mkiss_put(ax); - if (test_and_clear_bit(TTY_THROTTLED, &tty->flags) - && tty->ops->unthrottle) - tty->ops->unthrottle(tty); + tty_unthrottle(tty); } /* diff -u --new-file --recursive --exclude-from /usr/src/exclude linux.vanilla-2.6.25-mm1/drivers/net/ppp_async.c linux-2.6.25-mm1/drivers/net/ppp_async.c --- linux.vanilla-2.6.25-mm1/drivers/net/ppp_async.c 2008-04-28 11:36:49.000000000 +0100 +++ linux-2.6.25-mm1/drivers/net/ppp_async.c 2008-04-14 14:28:29.000000000 +0100 @@ -361,9 +361,7 @@ if (!skb_queue_empty(&ap->rqueue)) tasklet_schedule(&ap->tsk); ap_put(ap); - if (test_and_clear_bit(TTY_THROTTLED, &tty->flags) - && tty->ops->unthrottle) - tty->ops->unthrottle(tty); + tty_unthrottle(tty); } static void diff -u --new-file --recursive --exclude-from /usr/src/exclude linux.vanilla-2.6.25-mm1/drivers/net/ppp_synctty.c linux-2.6.25-mm1/drivers/net/ppp_synctty.c --- linux.vanilla-2.6.25-mm1/drivers/net/ppp_synctty.c 2008-04-28 11:36:49.000000000 +0100 +++ linux-2.6.25-mm1/drivers/net/ppp_synctty.c 2008-04-14 14:28:46.000000000 +0100 @@ -401,9 +401,7 @@ if (!skb_queue_empty(&ap->rqueue)) tasklet_schedule(&ap->tsk); sp_put(ap); - if (test_and_clear_bit(TTY_THROTTLED, &tty->flags) - && tty->ops->unthrottle) - tty->ops->unthrottle(tty); + tty_unthrottle(tty); } static void
| |