diff options
| author | Oliver Neukum <oliver@neukum.org> | 2009-10-07 10:50:23 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2009-10-09 13:52:09 -0700 |
| commit | 638325154572ba2113a18669fe3b299caa2dabd9 (patch) | |
| tree | c562a8460be432facbbba11288edaceba5ecbf1c /drivers/usb/serial/mct_u232.c | |
| parent | b2a5cf1bdc011f5474c72543f9d8116c0f07f452 (diff) | |
USB: serial: fix assumption that throttle/unthrottle cannot sleep
many serial subdrivers are clearly written as if throttle/unthrottle
cannot sleep. This leads to unneeded atomic submissions. This
patch converts affected drivers in a way to makes very clear that
throttle/unthrottle can sleep. Thus future misdesigns can be avoided
and efficiency and reliability improved.
This removes any such assumption using GFP_KERNEL and spin_lock_irq()
Signed-off-by: Oliver Neukum <oliver@neukum.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/usb/serial/mct_u232.c')
| -rw-r--r-- | drivers/usb/serial/mct_u232.c | 14 |
1 files changed, 6 insertions, 8 deletions
diff --git a/drivers/usb/serial/mct_u232.c b/drivers/usb/serial/mct_u232.c index ad4998bbf16f..cd009cb280a5 100644 --- a/drivers/usb/serial/mct_u232.c +++ b/drivers/usb/serial/mct_u232.c @@ -777,20 +777,19 @@ static void mct_u232_throttle(struct tty_struct *tty) { struct usb_serial_port *port = tty->driver_data; struct mct_u232_private *priv = usb_get_serial_port_data(port); - unsigned long flags; unsigned int control_state; dbg("%s - port %d", __func__, port->number); - spin_lock_irqsave(&priv->lock, flags); + spin_lock_irq(&priv->lock); priv->rx_flags |= THROTTLED; if (C_CRTSCTS(tty)) { priv->control_state &= ~TIOCM_RTS; control_state = priv->control_state; - spin_unlock_irqrestore(&priv->lock, flags); + spin_unlock_irq(&priv->lock); (void) mct_u232_set_modem_ctrl(port->serial, control_state); } else { - spin_unlock_irqrestore(&priv->lock, flags); + spin_unlock_irq(&priv->lock); } } @@ -799,20 +798,19 @@ static void mct_u232_unthrottle(struct tty_struct *tty) { struct usb_serial_port *port = tty->driver_data; struct mct_u232_private *priv = usb_get_serial_port_data(port); - unsigned long flags; unsigned int control_state; dbg("%s - port %d", __func__, port->number); - spin_lock_irqsave(&priv->lock, flags); + spin_lock_irq(&priv->lock); if ((priv->rx_flags & THROTTLED) && C_CRTSCTS(tty)) { priv->rx_flags &= ~THROTTLED; priv->control_state |= TIOCM_RTS; control_state = priv->control_state; - spin_unlock_irqrestore(&priv->lock, flags); + spin_unlock_irq(&priv->lock); (void) mct_u232_set_modem_ctrl(port->serial, control_state); } else { - spin_unlock_irqrestore(&priv->lock, flags); + spin_unlock_irq(&priv->lock); } } |