summaryrefslogtreecommitdiffstats
path: root/drivers
diff options
context:
space:
mode:
authorPeter Hurley <peter@hurleysoftware.com>2015-10-10 16:00:55 -0400
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2015-10-17 21:11:29 -0700
commit9b9ab1b3f0860138681862cf6e4c48be59377ef1 (patch)
tree5dcd70bcb2ab9a42db39a5c7d5311f08795d4a89 /drivers
parentcc2aaabfd6d6335e2156781ca67715b4de17f993 (diff)
downloadop-kernel-dev-9b9ab1b3f0860138681862cf6e4c48be59377ef1.zip
op-kernel-dev-9b9ab1b3f0860138681862cf6e4c48be59377ef1.tar.gz
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>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/tty/n_r3964.c10
1 files changed, 4 insertions, 6 deletions
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 @@ static void remove_from_tx_queue(struct r3964_info *pInfo, int error_code)
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 @@ static void on_receive_block(struct r3964_info *pInfo)
pBlock);
}
}
- wake_up_interruptible(&pInfo->read_wait);
+ wake_up_interruptible(&pInfo->tty->read_wait);
pInfo->state = R3964_IDLE;
@@ -979,7 +979,6 @@ static int r3964_open(struct tty_struct *tty)
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 @@ static void r3964_close(struct tty_struct *tty)
}
/* 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 @@ static ssize_t r3964_read(struct tty_struct *tty, struct file *file,
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 @@ static unsigned int r3964_poll(struct tty_struct *tty, struct file *file,
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);
OpenPOWER on IntegriCloud