tty: r3964: Use tty->read_wait waitqueue
The tty core provides read_wait waitqueue specifically for line
disciplines to wait readers; otherwise, the line discipline may
miss wakeups generated by the tty core.
NB: The tty core already provides serialization for the line discipline's
close() method, and guarantees no readers or writers will be using the
closing instance of the line discipline. Completely remove that wakeup.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/n_r3964.c b/drivers/tty/n_r3964.c
index 8b157d6..6fdef92 100644
--- a/drivers/tty/n_r3964.c
+++ b/drivers/tty/n_r3964.c
@@ -276,7 +276,7 @@
add_msg(pHeader->owner, R3964_MSG_ACK, pHeader->length,
error_code, NULL);
}
- wake_up_interruptible(&pInfo->read_wait);
+ wake_up_interruptible(&pInfo->tty->read_wait);
}
spin_lock_irqsave(&pInfo->lock, flags);
@@ -542,7 +542,7 @@
pBlock);
}
}
- wake_up_interruptible(&pInfo->read_wait);
+ wake_up_interruptible(&pInfo->tty->read_wait);
pInfo->state = R3964_IDLE;
@@ -979,7 +979,6 @@
spin_lock_init(&pInfo->lock);
pInfo->tty = tty;
- init_waitqueue_head(&pInfo->read_wait);
pInfo->priority = R3964_MASTER;
pInfo->rx_first = pInfo->rx_last = NULL;
pInfo->tx_first = pInfo->tx_last = NULL;
@@ -1045,7 +1044,6 @@
}
/* Free buffers: */
- wake_up_interruptible(&pInfo->read_wait);
kfree(pInfo->rx_buf);
TRACE_M("r3964_close - rx_buf kfree %p", pInfo->rx_buf);
kfree(pInfo->tx_buf);
@@ -1077,7 +1075,7 @@
goto unlock;
}
/* block until there is a message: */
- wait_event_interruptible_tty(tty, pInfo->read_wait,
+ wait_event_interruptible_tty(tty, tty->read_wait,
(pMsg = remove_msg(pInfo, pClient)));
}
@@ -1227,7 +1225,7 @@
pClient = findClient(pInfo, task_pid(current));
if (pClient) {
- poll_wait(file, &pInfo->read_wait, wait);
+ poll_wait(file, &tty->read_wait, wait);
spin_lock_irqsave(&pInfo->lock, flags);
pMsg = pClient->first_msg;
spin_unlock_irqrestore(&pInfo->lock, flags);