[1/9] ath9k_htc: Simplify TX URB management

Commit Message

Sujith April 22, 2010, 3:43 a.m. UTC

None

Patch

diff --git a/drivers/net/wireless/ath/ath9k/hif_usb.c b/drivers/net/wireless/ath/ath9k/hif_usb.c
index 3091bb3..cee5feb 100644
--- a/drivers/net/wireless/ath/ath9k/hif_usb.c
+++ b/drivers/net/wireless/ath/ath9k/hif_usb.c
@@ -93,14 +93,24 @@  static int hif_usb_send_regout(struct hif_device_usb *hif_dev,
 	return ret;
 }
 
+static inline void ath9k_skb_queue_purge(struct hif_device_usb *hif_dev,
+					 struct sk_buff_head *list)
+{
+	struct sk_buff *skb;
+
+	while ((skb = __skb_dequeue(list)) != NULL) {
+		dev_kfree_skb_any(skb);
+		TX_STAT_INC(skb_dropped);
+	}
+}
+
 static void hif_usb_tx_cb(struct urb *urb)
 {
 	struct tx_buf *tx_buf = (struct tx_buf *) urb->context;
 	struct hif_device_usb *hif_dev = tx_buf->hif_dev;
 	struct sk_buff *skb;
-	bool drop, flush;
 
-	if (!hif_dev)
+	if (!hif_dev || !tx_buf)
 		return;
 
 	switch (urb->status) {
@@ -108,57 +118,47 @@  static void hif_usb_tx_cb(struct urb *urb)
 		break;
 	case -ENOENT:
 	case -ECONNRESET:
-		break;
 	case -ENODEV:
 	case -ESHUTDOWN:
+		/*
+		 * The URB has been killed, free the SKBs
+		 * and return.
+		 */
+		ath9k_skb_queue_purge(hif_dev, &tx_buf->skb_queue);
 		return;
 	default:
 		break;
 	}
 
-	if (tx_buf) {
-		spin_lock(&hif_dev->tx.tx_lock);
-		drop = !!(hif_dev->tx.flags & HIF_USB_TX_STOP);
-		flush = !!(hif_dev->tx.flags & HIF_USB_TX_FLUSH);
-		spin_unlock(&hif_dev->tx.tx_lock);
-
-		while ((skb = __skb_dequeue(&tx_buf->skb_queue)) != NULL) {
-			if (!drop && !flush) {
-				ath9k_htc_txcompletion_cb(hif_dev->htc_handle,
-							  skb, 1);
-				TX_STAT_INC(skb_completed);
-			} else {
-				dev_kfree_skb_any(skb);
-				TX_STAT_INC(skb_dropped);
-			}
-		}
-
-		if (flush)
-			return;
-
-		tx_buf->len = tx_buf->offset = 0;
-		__skb_queue_head_init(&tx_buf->skb_queue);
-
-		spin_lock(&hif_dev->tx.tx_lock);
-		list_del(&tx_buf->list);
-		list_add_tail(&tx_buf->list, &hif_dev->tx.tx_buf);
-		hif_dev->tx.tx_buf_cnt++;
-		if (!drop)
-			__hif_usb_tx(hif_dev); /* Check for pending SKBs */
-		TX_STAT_INC(buf_completed);
+	/* Check if TX has been stopped */
+	spin_lock(&hif_dev->tx.tx_lock);
+	if (hif_dev->tx.flags & HIF_USB_TX_STOP) {
 		spin_unlock(&hif_dev->tx.tx_lock);
-	}
-}
-
-static inline void ath9k_skb_queue_purge(struct hif_device_usb *hif_dev,
-					 struct sk_buff_head *list)
-{
-	struct sk_buff *skb;
-
-	while ((skb = __skb_dequeue(list)) != NULL) {
-		dev_kfree_skb_any(skb);
-		TX_STAT_INC(skb_dropped);
-	}
+		ath9k_skb_queue_purge(hif_dev, &tx_buf->skb_queue);
+		goto add_free;
+	}
+	spin_unlock(&hif_dev->tx.tx_lock);
+
+	/* Complete the queued SKBs. */
+	while ((skb = __skb_dequeue(&tx_buf->skb_queue)) != NULL) {
+		ath9k_htc_txcompletion_cb(hif_dev->htc_handle,
+					  skb, 1);
+		TX_STAT_INC(skb_completed);
+	}
+
+add_free:
+	/* Re-initialize the SKB queue */
+	tx_buf->len = tx_buf->offset = 0;
+	__skb_queue_head_init(&tx_buf->skb_queue);
+
+	/* Add this TX buffer to the free list */
+	spin_lock(&hif_dev->tx.tx_lock);
+	list_move_tail(&tx_buf->list, &hif_dev->tx.tx_buf);
+	hif_dev->tx.tx_buf_cnt++;
+	if (!(hif_dev->tx.flags & HIF_USB_TX_STOP))
+		__hif_usb_tx(hif_dev); /* Check for pending SKBs */
+	TX_STAT_INC(buf_completed);
+	spin_unlock(&hif_dev->tx.tx_lock);
 }
 
 /* TX lock has to be taken */
@@ -178,8 +178,7 @@  static int __hif_usb_tx(struct hif_device_usb *hif_dev)
 		return 0;
 
 	tx_buf = list_first_entry(&hif_dev->tx.tx_buf, struct tx_buf, list);
-	list_del(&tx_buf->list);
-	list_add_tail(&tx_buf->list, &hif_dev->tx.tx_pending);
+	list_move_tail(&tx_buf->list, &hif_dev->tx.tx_pending);
 	hif_dev->tx.tx_buf_cnt--;
 
 	tx_skb_cnt = min_t(u16, hif_dev->tx.tx_skb_cnt, MAX_TX_AGGR_NUM);
@@ -548,20 +547,17 @@  free:
 
 static void ath9k_hif_usb_dealloc_tx_urbs(struct hif_device_usb *hif_dev)
 {
-	unsigned long flags;
 	struct tx_buf *tx_buf = NULL, *tx_buf_tmp = NULL;
 
-	list_for_each_entry_safe(tx_buf, tx_buf_tmp, &hif_dev->tx.tx_buf, list) {
+	list_for_each_entry_safe(tx_buf, tx_buf_tmp,
+				 &hif_dev->tx.tx_buf, list) {
+		usb_kill_urb(tx_buf->urb);
 		list_del(&tx_buf->list);
 		usb_free_urb(tx_buf->urb);
 		kfree(tx_buf->buf);
 		kfree(tx_buf);
 	}
 
-	spin_lock_irqsave(&hif_dev->tx.tx_lock, flags);
-	hif_dev->tx.flags |= HIF_USB_TX_FLUSH;
-	spin_unlock_irqrestore(&hif_dev->tx.tx_lock, flags);
-
 	list_for_each_entry_safe(tx_buf, tx_buf_tmp,
 				 &hif_dev->tx.tx_pending, list) {
 		usb_kill_urb(tx_buf->urb);
@@ -570,10 +566,6 @@  static void ath9k_hif_usb_dealloc_tx_urbs(struct hif_device_usb *hif_dev)
 		kfree(tx_buf->buf);
 		kfree(tx_buf);
 	}
-
-	spin_lock_irqsave(&hif_dev->tx.tx_lock, flags);
-	hif_dev->tx.flags &= ~HIF_USB_TX_FLUSH;
-	spin_unlock_irqrestore(&hif_dev->tx.tx_lock, flags);
 }
 
 static int ath9k_hif_usb_alloc_tx_urbs(struct hif_device_usb *hif_dev)
diff --git a/drivers/net/wireless/ath/ath9k/hif_usb.h b/drivers/net/wireless/ath/ath9k/hif_usb.h
index 7d49a8a..0aca49b 100644
--- a/drivers/net/wireless/ath/ath9k/hif_usb.h
+++ b/drivers/net/wireless/ath/ath9k/hif_usb.h
@@ -61,7 +61,6 @@  struct tx_buf {
 };
 
 #define HIF_USB_TX_STOP  BIT(0)
-#define HIF_USB_TX_FLUSH BIT(1)
 
 struct hif_usb_tx {
 	u8 flags;