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>
diff --git a/drivers/net/wireless/rt2x00/rt2400pci.c b/drivers/net/wireless/rt2x00/rt2400pci.c
index 94226b4..b5b0ded 100644
--- a/drivers/net/wireless/rt2x00/rt2400pci.c
+++ b/drivers/net/wireless/rt2x00/rt2400pci.c
@@ -1507,7 +1507,6 @@
*/
skbdesc = get_skb_frame_desc(skb);
memset(skbdesc, 0, sizeof(*skbdesc));
- skbdesc->flags |= FRAME_DESC_DRIVER_GENERATED;
skbdesc->data = skb->data;
skbdesc->data_len = skb->len;
skbdesc->desc = entry_priv->desc;
diff --git a/drivers/net/wireless/rt2x00/rt2500pci.c b/drivers/net/wireless/rt2x00/rt2500pci.c
index c8cf8c1..74b54c9 100644
--- a/drivers/net/wireless/rt2x00/rt2500pci.c
+++ b/drivers/net/wireless/rt2x00/rt2500pci.c
@@ -1823,7 +1823,6 @@
*/
skbdesc = get_skb_frame_desc(skb);
memset(skbdesc, 0, sizeof(*skbdesc));
- skbdesc->flags |= FRAME_DESC_DRIVER_GENERATED;
skbdesc->data = skb->data;
skbdesc->data_len = skb->len;
skbdesc->desc = entry_priv->desc;
diff --git a/drivers/net/wireless/rt2x00/rt2500usb.c b/drivers/net/wireless/rt2x00/rt2500usb.c
index 6abb4c5..0762214 100644
--- a/drivers/net/wireless/rt2x00/rt2500usb.c
+++ b/drivers/net/wireless/rt2x00/rt2500usb.c
@@ -1711,7 +1711,6 @@
*/
skbdesc = get_skb_frame_desc(skb);
memset(skbdesc, 0, sizeof(*skbdesc));
- skbdesc->flags |= FRAME_DESC_DRIVER_GENERATED;
skbdesc->data = skb->data + intf->beacon->queue->desc_size;
skbdesc->data_len = skb->len - intf->beacon->queue->desc_size;
skbdesc->desc = skb->data;
diff --git a/drivers/net/wireless/rt2x00/rt2x00.h b/drivers/net/wireless/rt2x00/rt2x00.h
index c7da3c2..938d375 100644
--- a/drivers/net/wireless/rt2x00/rt2x00.h
+++ b/drivers/net/wireless/rt2x00/rt2x00.h
@@ -826,7 +826,7 @@
* The Beacon array also contains the Atim queue
* if that is supported by the device.
*/
- int data_queues;
+ unsigned int data_queues;
struct data_queue *rx;
struct data_queue *tx;
struct data_queue *bcn;
diff --git a/drivers/net/wireless/rt2x00/rt2x00mac.c b/drivers/net/wireless/rt2x00/rt2x00mac.c
index e7f544c..59f273b 100644
--- a/drivers/net/wireless/rt2x00/rt2x00mac.c
+++ b/drivers/net/wireless/rt2x00/rt2x00mac.c
@@ -34,7 +34,6 @@
struct sk_buff *frag_skb)
{
struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(frag_skb);
- struct skb_frame_desc *skbdesc;
struct ieee80211_tx_info *rts_info;
struct sk_buff *skb;
int size;
@@ -82,13 +81,6 @@
frag_skb->data, size, tx_info,
(struct ieee80211_rts *)(skb->data));
- /*
- * Initialize skb descriptor
- */
- skbdesc = get_skb_frame_desc(skb);
- memset(skbdesc, 0, sizeof(*skbdesc));
- skbdesc->flags |= FRAME_DESC_DRIVER_GENERATED;
-
if (rt2x00queue_write_tx_frame(queue, skb)) {
WARNING(rt2x00dev, "Failed to send RTS/CTS frame.\n");
return NETDEV_TX_BUSY;
@@ -163,7 +155,7 @@
return NETDEV_TX_BUSY;
}
- if (rt2x00queue_full(queue))
+ if (rt2x00queue_threshold(queue))
ieee80211_stop_queue(rt2x00dev->hw, qid);
return NETDEV_TX_OK;
diff --git a/drivers/net/wireless/rt2x00/rt2x00pci.c b/drivers/net/wireless/rt2x00/rt2x00pci.c
index a6bac75..9745277 100644
--- a/drivers/net/wireless/rt2x00/rt2x00pci.c
+++ b/drivers/net/wireless/rt2x00/rt2x00pci.c
@@ -170,11 +170,11 @@
rt2x00queue_index_inc(entry->queue, Q_INDEX_DONE);
/*
- * If the data queue was full before the txdone handler
- * we must make sure the packet queue in the mac80211 stack
+ * If the data queue was below the threshold before the txdone
+ * handler we must make sure the packet queue in the mac80211 stack
* is reenabled when the txdone handler has finished.
*/
- if (!rt2x00queue_full(entry->queue))
+ if (!rt2x00queue_threshold(entry->queue))
ieee80211_wake_queue(rt2x00dev->hw, qid);
}
diff --git a/drivers/net/wireless/rt2x00/rt2x00queue.c b/drivers/net/wireless/rt2x00/rt2x00queue.c
index f875b7a..4930665 100644
--- a/drivers/net/wireless/rt2x00/rt2x00queue.c
+++ b/drivers/net/wireless/rt2x00/rt2x00queue.c
@@ -163,8 +163,8 @@
void rt2x00queue_write_tx_descriptor(struct queue_entry *entry,
struct txentry_desc *txdesc)
{
- struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
- struct skb_frame_desc *skbdesc = get_skb_frame_desc(entry->skb);
+ struct data_queue *queue = entry->queue;
+ struct rt2x00_dev *rt2x00dev = queue->rt2x00dev;
rt2x00dev->ops->lib->write_tx_desc(rt2x00dev, entry->skb, txdesc);
@@ -175,16 +175,21 @@
rt2x00debug_dump_frame(rt2x00dev, DUMP_FRAME_TX, entry->skb);
/*
- * We are done writing the frame to the queue entry,
- * also kick the queue in case the correct flags are set,
- * note that this will automatically filter beacons and
- * RTS/CTS frames since those frames don't have this flag
- * set.
+ * Check if we need to kick the queue, there are however a few rules
+ * 1) Don't kick beacon queue
+ * 2) Don't kick unless this is the last in frame in a burst.
+ * When the burst flag is set, this frame is always followed
+ * by another frame which in some way are related to eachother.
+ * This is true for fragments, RTS or CTS-to-self frames.
+ * 3) Rule 2 can be broken when the available entries
+ * in the queue are less then a certain threshold.
*/
- if (rt2x00dev->ops->lib->kick_tx_queue &&
- !(skbdesc->flags & FRAME_DESC_DRIVER_GENERATED))
- rt2x00dev->ops->lib->kick_tx_queue(rt2x00dev,
- entry->queue->qid);
+ if (entry->queue->qid == QID_BEACON)
+ return;
+
+ if (rt2x00queue_threshold(queue) ||
+ !test_bit(ENTRY_TXD_BURST, &txdesc->flags))
+ rt2x00dev->ops->lib->kick_tx_queue(rt2x00dev, queue->qid);
}
EXPORT_SYMBOL_GPL(rt2x00queue_write_tx_descriptor);
@@ -349,6 +354,7 @@
rt2x00queue_reset(queue);
queue->limit = qdesc->entry_num;
+ queue->threshold = DIV_ROUND_UP(qdesc->entry_num, 10);
queue->data_size = qdesc->data_size;
queue->desc_size = qdesc->desc_size;
diff --git a/drivers/net/wireless/rt2x00/rt2x00queue.h b/drivers/net/wireless/rt2x00/rt2x00queue.h
index 303d556..623fc27 100644
--- a/drivers/net/wireless/rt2x00/rt2x00queue.h
+++ b/drivers/net/wireless/rt2x00/rt2x00queue.h
@@ -82,12 +82,10 @@
/**
* 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 @@
* 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 @@
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 @@
}
/**
+ * 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.
diff --git a/drivers/net/wireless/rt2x00/rt2x00usb.c b/drivers/net/wireless/rt2x00/rt2x00usb.c
index fdf505b..8cf6e3f 100644
--- a/drivers/net/wireless/rt2x00/rt2x00usb.c
+++ b/drivers/net/wireless/rt2x00/rt2x00usb.c
@@ -165,11 +165,11 @@
rt2x00queue_index_inc(entry->queue, Q_INDEX_DONE);
/*
- * If the data queue was full before the txdone handler
- * we must make sure the packet queue in the mac80211 stack
+ * If the data queue was below the threshold before the txdone
+ * handler we must make sure the packet queue in the mac80211 stack
* is reenabled when the txdone handler has finished.
*/
- if (!rt2x00queue_full(entry->queue))
+ if (!rt2x00queue_threshold(entry->queue))
ieee80211_wake_queue(rt2x00dev->hw, qid);
}
diff --git a/drivers/net/wireless/rt2x00/rt61pci.c b/drivers/net/wireless/rt2x00/rt61pci.c
index aa9ef66..746f87c8 100644
--- a/drivers/net/wireless/rt2x00/rt61pci.c
+++ b/drivers/net/wireless/rt2x00/rt61pci.c
@@ -2375,7 +2375,6 @@
*/
skbdesc = get_skb_frame_desc(skb);
memset(skbdesc, 0, sizeof(*skbdesc));
- skbdesc->flags |= FRAME_DESC_DRIVER_GENERATED;
skbdesc->data = skb->data;
skbdesc->data_len = skb->len;
skbdesc->desc = entry_priv->desc;
diff --git a/drivers/net/wireless/rt2x00/rt73usb.c b/drivers/net/wireless/rt2x00/rt73usb.c
index 5e5f603..ae50f63 100644
--- a/drivers/net/wireless/rt2x00/rt73usb.c
+++ b/drivers/net/wireless/rt2x00/rt73usb.c
@@ -1980,7 +1980,6 @@
*/
skbdesc = get_skb_frame_desc(skb);
memset(skbdesc, 0, sizeof(*skbdesc));
- skbdesc->flags |= FRAME_DESC_DRIVER_GENERATED;
skbdesc->data = skb->data + intf->beacon->queue->desc_size;
skbdesc->data_len = skb->len - intf->beacon->queue->desc_size;
skbdesc->desc = skb->data;