rt2x00: Move TX/RX work into dedicated workqueue

The TX/RX work structures must be able to run independently
of other workqueues. This is because mac80211 might use
the flush() callback function from various context, which depends
on the TX/RX work to complete while the main thread is blocked
(until the the TX queues are empty).

This should reduce the number of  'Queue %d failed to flush' warnings.

Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Acked-by: Gertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

4 files changed, 25 insertions, 7 deletions

diff --git a/drivers/net/wireless/rt2x00/rt2x00.h b/drivers/net/wireless/rt2x00/rt2x00.h
index 7661e4f60ddc..39bc2faf1793 100644
--- a/drivers/net/wireless/rt2x00/rt2x00.h
+++ b/drivers/net/wireless/rt2x00/rt2x00.h
@@ -860,6 +860,13 @@ struct rt2x00_dev {
          */
         struct ieee80211_low_level_stats low_level_stats;
 
+        /**
+         * Work queue for all work which should not be placed
+         * on the mac80211 workqueue (because of dependencies
+         * between various work structures).
+         */
+        struct workqueue_struct *workqueue;
+
         /*
          * Scheduled work.
          * NOTE: intf_work will use ieee80211_iterate_active_interfaces()
diff --git a/drivers/net/wireless/rt2x00/rt2x00dev.c b/drivers/net/wireless/rt2x00/rt2x00dev.c
index e7162852ec34..9de9dbe94399 100644
--- a/drivers/net/wireless/rt2x00/rt2x00dev.c
+++ b/drivers/net/wireless/rt2x00/rt2x00dev.c
@@ -997,8 +997,15 @@ int rt2x00lib_probe_dev(struct rt2x00_dev *rt2x00dev)
                     BIT(NL80211_IFTYPE_WDS);
 
         /*
-         * Initialize configuration work.
+         * Initialize work.
          */
+        rt2x00dev->workqueue =
+            alloc_ordered_workqueue(wiphy_name(rt2x00dev->hw->wiphy), 0);
+        if (!rt2x00dev->workqueue) {
+                retval = -ENOMEM;
+                goto exit;
+        }
+
         INIT_WORK(&rt2x00dev->intf_work, rt2x00lib_intf_scheduled);
 
         /*
@@ -1057,6 +1064,7 @@ void rt2x00lib_remove_dev(struct rt2x00_dev *rt2x00dev)
         cancel_work_sync(&rt2x00dev->intf_work);
         cancel_work_sync(&rt2x00dev->rxdone_work);
         cancel_work_sync(&rt2x00dev->txdone_work);
+        destroy_workqueue(rt2x00dev->workqueue);
 
         /*
          * Free the tx status fifo.
diff --git a/drivers/net/wireless/rt2x00/rt2x00link.c b/drivers/net/wireless/rt2x00/rt2x00link.c
index bfda60eaf4ef..c975b0a12e95 100644
--- a/drivers/net/wireless/rt2x00/rt2x00link.c
+++ b/drivers/net/wireless/rt2x00/rt2x00link.c
@@ -417,7 +417,8 @@ void rt2x00link_start_watchdog(struct rt2x00_dev *rt2x00dev)
             !test_bit(DRIVER_SUPPORT_WATCHDOG, &rt2x00dev->flags))
                 return;
 
-        schedule_delayed_work(&link->watchdog_work, WATCHDOG_INTERVAL);
+        ieee80211_queue_delayed_work(rt2x00dev->hw,
+                                     &link->watchdog_work, WATCHDOG_INTERVAL);
 }
 
 void rt2x00link_stop_watchdog(struct rt2x00_dev *rt2x00dev)
@@ -441,7 +442,9 @@ static void rt2x00link_watchdog(struct work_struct *work)
         rt2x00dev->ops->lib->watchdog(rt2x00dev);
 
         if (test_bit(DEVICE_STATE_PRESENT, &rt2x00dev->flags))
-                schedule_delayed_work(&link->watchdog_work, WATCHDOG_INTERVAL);
+                ieee80211_queue_delayed_work(rt2x00dev->hw,
+                                             &link->watchdog_work,
+                                             WATCHDOG_INTERVAL);
 }
 
 void rt2x00link_register(struct rt2x00_dev *rt2x00dev)
diff --git a/drivers/net/wireless/rt2x00/rt2x00usb.c b/drivers/net/wireless/rt2x00/rt2x00usb.c
index 1a9937d5aff6..fbe735f5b352 100644
--- a/drivers/net/wireless/rt2x00/rt2x00usb.c
+++ b/drivers/net/wireless/rt2x00/rt2x00usb.c
@@ -227,7 +227,7 @@ static void rt2x00usb_interrupt_txdone(struct urb *urb)
          * Schedule the delayed work for reading the TX status
          * from the device.
          */
-        ieee80211_queue_work(rt2x00dev->hw, &rt2x00dev->txdone_work);
+        queue_work(rt2x00dev->workqueue, &rt2x00dev->txdone_work);
 }
 
 static void rt2x00usb_kick_tx_entry(struct queue_entry *entry)
@@ -320,7 +320,7 @@ static void rt2x00usb_interrupt_rxdone(struct urb *urb)
          * Schedule the delayed work for reading the RX status
          * from the device.
          */
-        ieee80211_queue_work(rt2x00dev->hw, &rt2x00dev->rxdone_work);
+        queue_work(rt2x00dev->workqueue, &rt2x00dev->rxdone_work);
 }
 
 static void rt2x00usb_kick_rx_entry(struct queue_entry *entry)
@@ -429,7 +429,7 @@ void rt2x00usb_flush_queue(struct data_queue *queue)
                  * Schedule the completion handler manually, when this
                  * worker function runs, it should cleanup the queue.
                  */
-                ieee80211_queue_work(queue->rt2x00dev->hw, completion);
+                queue_work(queue->rt2x00dev->workqueue, completion);
 
                 /*
                  * Wait for a little while to give the driver
@@ -453,7 +453,7 @@ static void rt2x00usb_watchdog_tx_status(struct data_queue *queue)
         WARNING(queue->rt2x00dev, "TX queue %d status timed out,"
                 " invoke forced tx handler\n", queue->qid);
 
-        ieee80211_queue_work(queue->rt2x00dev->hw, &queue->rt2x00dev->txdone_work);
+        queue_work(queue->rt2x00dev->workqueue, &queue->rt2x00dev->txdone_work);
 }
 
 void rt2x00usb_watchdog(struct rt2x00_dev *rt2x00dev)