diff options
author | Johan Hovold <johan@kernel.org> | 2019-04-25 19:05:37 +0300 |
---|---|---|
committer | Johan Hovold <johan@kernel.org> | 2019-04-30 11:23:29 +0300 |
commit | a8d78d9f385642696723fcb9c52c2c2805fa4249 (patch) | |
tree | 368433304e6f08f7855b4187ba4ce6fd4f6b235a /drivers/usb | |
parent | 3f5edd58d040bfa4b74fb89bc02f0bc6b9cd06ab (diff) | |
download | linux-a8d78d9f385642696723fcb9c52c2c2805fa4249.tar.xz |
USB: serial: clean up throttle handling
Clean up the throttle implementation by dropping the redundant
throttle_req flag which was a remnant from back when there was only a
single read URB.
Also convert the throttled flag to an atomic bit flag.
Signed-off-by: Johan Hovold <johan@kernel.org>
Diffstat (limited to 'drivers/usb')
-rw-r--r-- | drivers/usb/serial/generic.c | 34 |
1 files changed, 8 insertions, 26 deletions
diff --git a/drivers/usb/serial/generic.c b/drivers/usb/serial/generic.c index 0fff4968ea1b..67cef3ef1e5f 100644 --- a/drivers/usb/serial/generic.c +++ b/drivers/usb/serial/generic.c @@ -106,12 +106,8 @@ void usb_serial_generic_deregister(void) int usb_serial_generic_open(struct tty_struct *tty, struct usb_serial_port *port) { int result = 0; - unsigned long flags; - spin_lock_irqsave(&port->lock, flags); - port->throttled = 0; - port->throttle_req = 0; - spin_unlock_irqrestore(&port->lock, flags); + clear_bit(USB_SERIAL_THROTTLED, &port->flags); if (port->bulk_in_size) result = usb_serial_generic_submit_read_urbs(port, GFP_KERNEL); @@ -375,7 +371,6 @@ void usb_serial_generic_read_bulk_callback(struct urb *urb) { struct usb_serial_port *port = urb->context; unsigned char *data = urb->transfer_buffer; - unsigned long flags; bool stopped = false; int status = urb->status; int i; @@ -429,15 +424,10 @@ void usb_serial_generic_read_bulk_callback(struct urb *urb) if (stopped) return; - /* Throttle the device if requested by tty */ - spin_lock_irqsave(&port->lock, flags); - port->throttled = port->throttle_req; - if (!port->throttled) { - spin_unlock_irqrestore(&port->lock, flags); - usb_serial_generic_submit_read_urb(port, i, GFP_ATOMIC); - } else { - spin_unlock_irqrestore(&port->lock, flags); - } + if (test_bit(USB_SERIAL_THROTTLED, &port->flags)) + return; + + usb_serial_generic_submit_read_urb(port, i, GFP_ATOMIC); } EXPORT_SYMBOL_GPL(usb_serial_generic_read_bulk_callback); @@ -485,23 +475,16 @@ EXPORT_SYMBOL_GPL(usb_serial_generic_write_bulk_callback); void usb_serial_generic_throttle(struct tty_struct *tty) { struct usb_serial_port *port = tty->driver_data; - unsigned long flags; - spin_lock_irqsave(&port->lock, flags); - port->throttle_req = 1; - spin_unlock_irqrestore(&port->lock, flags); + set_bit(USB_SERIAL_THROTTLED, &port->flags); } EXPORT_SYMBOL_GPL(usb_serial_generic_throttle); void usb_serial_generic_unthrottle(struct tty_struct *tty) { struct usb_serial_port *port = tty->driver_data; - int was_throttled; - spin_lock_irq(&port->lock); - was_throttled = port->throttled; - port->throttled = port->throttle_req = 0; - spin_unlock_irq(&port->lock); + clear_bit(USB_SERIAL_THROTTLED, &port->flags); /* * Matches the smp_mb__after_atomic() in @@ -509,8 +492,7 @@ void usb_serial_generic_unthrottle(struct tty_struct *tty) */ smp_mb(); - if (was_throttled) - usb_serial_generic_submit_read_urbs(port, GFP_KERNEL); + usb_serial_generic_submit_read_urbs(port, GFP_KERNEL); } EXPORT_SYMBOL_GPL(usb_serial_generic_unthrottle); |