rt2x00: Don't kick TX queue after each frame

TX queues shouldn't be kicked after each frame that is put into the
queue.  This could cause problems during RTS and CTS-to-self as well
as with fragmentation. In all those cases you want all frames to be
send out in a single burst. Off course we shouldn't let the queue fill
up entirely, thus we introduce a 10% threshold which, when reached,
will force the frames to be send out regardless of the frame.

In addition we should prevent queues to become full in such a way
that the tx() handler can fail. Instead of stopping the queue when
it is full, we should stop it when it is below the threshold.

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

1 files changed, 14 insertions, 5 deletions

diff --git a/drivers/net/wireless/rt2x00/rt2x00queue.h b/drivers/net/wireless/rt2x00/rt2x00queue.h
index 303d5568470d..623fc27dc7bb 100644
--- a/drivers/net/wireless/rt2x00/rt2x00queue.h
+++ b/drivers/net/wireless/rt2x00/rt2x00queue.h
@@ -82,12 +82,10 @@ enum data_queue_qid {
 /**
  * enum skb_frame_desc_flags: Flags for &struct skb_frame_desc
  *
- * @FRAME_DESC_DRIVER_GENERATED: Frame was generated inside driver
- *      and should not be reported back to mac80211 during txdone.
  */
-enum skb_frame_desc_flags {
-        FRAME_DESC_DRIVER_GENERATED = 1 << 0,
-};
+//enum skb_frame_desc_flags {
+//      TEMPORARILY EMPTY
+//};
 
 /**
  * struct skb_frame_desc: Descriptor information for the skb buffer
@@ -325,6 +323,7 @@ enum queue_index {
  *      index corruption due to concurrency.
  * @count: Number of frames handled in the queue.
  * @limit: Maximum number of entries in the queue.
+ * @threshold: Minimum number of free entries before queue is kicked by force.
  * @length: Number of frames in queue.
  * @index: Index pointers to entry positions in the queue,
  *      use &enum queue_index to get a specific index field.
@@ -343,6 +342,7 @@ struct data_queue {
         spinlock_t lock;
         unsigned int count;
         unsigned short limit;
+        unsigned short threshold;
         unsigned short length;
         unsigned short index[Q_INDEX_MAX];
 
@@ -467,6 +467,15 @@ static inline int rt2x00queue_available(struct data_queue *queue)
 }
 
 /**
+ * rt2x00queue_threshold - Check if the queue is below threshold
+ * @queue: Queue to check.
+ */
+static inline int rt2x00queue_threshold(struct data_queue *queue)
+{
+        return rt2x00queue_available(queue) < queue->threshold;
+}
+
+/**
  * rt2x00_desc_read - Read a word from the hardware descriptor.
  * @desc: Base descriptor address
  * @word: Word index from where the descriptor should be read.