Merge branch 'r8169-series-with-improvements-to-rtl_tx'

Heiner Kallweit says:

====================
r8169: series with improvements to rtl_tx

This series includes few improvements to rtl_tx().
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/realtek/r8169_main.c

@@ -3970,17 +3970,15 @@ static int rtl8169_init_ring(struct rtl8169_private *tp)
 	return rtl8169_rx_fill(tp);
 }
 
-static void rtl8169_unmap_tx_skb(struct device *d, struct ring_info *tx_skb,
-				 struct TxDesc *desc)
+static void rtl8169_unmap_tx_skb(struct rtl8169_private *tp, unsigned int entry)
 {
-	unsigned int len = tx_skb->len;
+	struct ring_info *tx_skb = tp->tx_skb + entry;
+	struct TxDesc *desc = tp->TxDescArray + entry;
 
-	dma_unmap_single(d, le64_to_cpu(desc->addr), len, DMA_TO_DEVICE);
-
-	desc->opts1 = 0x00;
-	desc->opts2 = 0x00;
-	desc->addr = 0x00;
-	tx_skb->len = 0;
+	dma_unmap_single(tp_to_dev(tp), le64_to_cpu(desc->addr), tx_skb->len,
+			 DMA_TO_DEVICE);
+	memset(desc, 0, sizeof(*desc));
+	memset(tx_skb, 0, sizeof(*tx_skb));
 }
 
 static void rtl8169_tx_clear_range(struct rtl8169_private *tp, u32 start,
@@ -3996,12 +3994,9 @@ static void rtl8169_tx_clear_range(struct rtl8169_private *tp, u32 start,
 		if (len) {
 			struct sk_buff *skb = tx_skb->skb;
 
-			rtl8169_unmap_tx_skb(tp_to_dev(tp), tx_skb,
-					     tp->TxDescArray + entry);
-			if (skb) {
+			rtl8169_unmap_tx_skb(tp, entry);
+			if (skb)
 				dev_consume_skb_any(skb);
-				tx_skb->skb = NULL;
-			}
 		}
 	}
 }
@@ -4308,7 +4303,7 @@ static netdev_tx_t rtl8169_start_xmit(struct sk_buff *skb,
 	return NETDEV_TX_OK;
 
 err_dma_1:
-	rtl8169_unmap_tx_skb(d, tp->tx_skb + entry, txd);
+	rtl8169_unmap_tx_skb(tp, entry);
 err_dma_0:
 	dev_kfree_skb_any(skb);
 	dev->stats.tx_dropped++;
@@ -4392,33 +4387,24 @@ static void rtl_tx(struct net_device *dev, struct rtl8169_private *tp,
 
 	dirty_tx = tp->dirty_tx;
 	smp_rmb();
-	tx_left = tp->cur_tx - dirty_tx;
 
-	while (tx_left > 0) {
+	for (tx_left = tp->cur_tx - dirty_tx; tx_left > 0; tx_left--) {
 		unsigned int entry = dirty_tx % NUM_TX_DESC;
-		struct ring_info *tx_skb = tp->tx_skb + entry;
+		struct sk_buff *skb = tp->tx_skb[entry].skb;
 		u32 status;
 
 		status = le32_to_cpu(tp->TxDescArray[entry].opts1);
 		if (status & DescOwn)
 			break;
 
-		/* This barrier is needed to keep us from reading
-		 * any other fields out of the Tx descriptor until
-		 * we know the status of DescOwn
-		 */
-		dma_rmb();
+		rtl8169_unmap_tx_skb(tp, entry);
 
-		rtl8169_unmap_tx_skb(tp_to_dev(tp), tx_skb,
-				     tp->TxDescArray + entry);
-		if (tx_skb->skb) {
+		if (skb) {
 			pkts_compl++;
-			bytes_compl += tx_skb->skb->len;
-			napi_consume_skb(tx_skb->skb, budget);
-			tx_skb->skb = NULL;
+			bytes_compl += skb->len;
+			napi_consume_skb(skb, budget);
 		}
 		dirty_tx++;
-		tx_left--;
 	}
 
 	if (tp->dirty_tx != dirty_tx) {