ucc_geth: Fix full TX queue processing

From: Jiajun Wu <[email protected]>

commit 7583605b6d29f1f7f6fc505b883328089f3485ad ("ucc_geth: Fix empty TX queue processing") fixed empty TX queue mishandling, but didn't account another corner case: when TX queue becomes full.

Without this patch the driver will stop transmiting when TX queue becomes full since 'bd == ugeth->txBd[txQ]' actually checks for two things: queue empty or full.

Let's better check for NULL skb, which unambiguously signals an empty queue.

---

OK, let's resend the patch with just !skb check?

 drivers/net/ucc_geth.c |    5 ++---
 1 files changed, 2 insertions(+), 3 deletions(-)

index 96bdc0b..eb8fe7e 100644
@@ -3279,13 +3279,12 @@ static int ucc_geth_tx(struct net_device *dev, u8 txQ)
 		/* Handle the transmitted buffer and release */
 		/* the BD to be used with the current frame  */
 
-		if (bd == ugeth->txBd[txQ]) /* queue empty? */
+		skb = ugeth->tx_skbuff[txQ][ugeth->skb_dirtytx[txQ]];
+		if (!skb)
 			break;
 
 		dev->stats.tx_packets++;
 
-		skb = ugeth->tx_skbuff[txQ][ugeth->skb_dirtytx[txQ]];
-
 		if (skb_queue_len(&ugeth->rx_recycle) < RX_BD_RING_LEN &&
 			     skb_recycle_check(skb,
 				    ugeth->ug_info->uf_info.max_rx_buf_length +

1.6.5.7

From: Anton Vorontsov <[email protected]>
Date: Mon, 18 Jan 2010 18:47:50 +0300

Applied.