[ 08/25] rt2x00: fix stop queue

Greg Kroah-Hartman
2013-08-09T01:43:17Z

From: Stanislaw Gruszka <stf_xl@wp.pl>

commit e2288b66fe7ff0288382b2af671b4da558b44472 upstream.

Since we clear QUEUE_STARTED in rt2x00queue_stop_queue(), following
call to rt2x00queue_pause_queue() reduce to noop, i.e we do not
stop queue in mac80211.

To fix that introduce rt2x00queue_pause_queue_nocheck() function,
which will stop queue in mac80211 directly.

Note that rt2x00_start_queue() explicitly set QUEUE_PAUSED bit.

Note also that reordering operations i.e. first call to
rt2x00queue_pause_queue() and then clear QUEUE_STARTED bit, will race
with rt2x00queue_unpause_queue(), so calling ieee80211_stop_queue()
directly is the only available solution to fix the problem without
major rework.

Signed-off-by: Stanislaw Gruszka <stf_xl@wp.pl>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/net/wireless/rt2x00/rt2x00queue.c | 18 +++++++++++-------
1 file changed, 11 insertions(+), 7 deletions(-)

--- a/drivers/net/wireless/rt2x00/rt2x00queue.c
+++ b/drivers/net/wireless/rt2x00/rt2x00queue.c
@@ -856,13 +856,8 @@ void rt2x00queue_index_inc(struct queue_
spin_unlock_irqrestore(&queue->index_lock, irqflags);
}

-void rt2x00queue_pause_queue(struct data_queue *queue)
+void rt2x00queue_pause_queue_nocheck(struct data_queue *queue)
{
- if (!test_bit(DEVICE_STATE_PRESENT, &queue->rt2x00dev->flags) ||
- !test_bit(QUEUE_STARTED, &queue->flags) ||
- test_and_set_bit(QUEUE_PAUSED, &queue->flags))
- return;
-
switch (queue->qid) {
case QID_AC_VO:
case QID_AC_VI:
@@ -878,6 +873,15 @@ void rt2x00queue_pause_queue(struct data
break;
}
}
+void rt2x00queue_pause_queue(struct data_queue *queue)
+{
+ if (!test_bit(DEVICE_STATE_PRESENT, &queue->rt2x00dev->flags) ||
+ !test_bit(QUEUE_STARTED, &queue->flags) ||
+ test_and_set_bit(QUEUE_PAUSED, &queue->flags))
+ return;
+
+ rt2x00queue_pause_queue_nocheck(queue);
+}
EXPORT_SYMBOL_GPL(rt2x00queue_pause_queue);

void rt2x00queue_unpause_queue(struct data_queue *queue)
@@ -939,7 +943,7 @@ void rt2x00queue_stop_queue(struct data_
return;
}

- rt2x00queue_pause_queue(queue);
+ rt2x00queue_pause_queue_nocheck(queue);

queue->rt2x00dev->ops->lib->stop_queue(queue);