[PATCH] mv643xx_eth: Rename mp->tx_ring_skbs to mp->tx_desc_count

tx_ring_skbs is actually a count of tx descriptors currently in use.
Since there may be multiple descriptors per skb, it is not the
same as the number of skbs in the ring.

Also change rx_ring_skbs to rx_desc_count to be consistent.

Signed-off-by: Dale Farnsworth <dale@farnsworth.org>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>

drivers/net/mv643xx_eth.c

@@ -169,11 +169,11 @@ static void mv643xx_eth_rx_task(void *data)
 	if (test_and_set_bit(0, &mp->rx_task_busy))
 		panic("%s: Error in test_set_bit / clear_bit", dev->name);
 
-	while (mp->rx_ring_skbs < (mp->rx_ring_size - 5)) {
+	while (mp->rx_desc_count < (mp->rx_ring_size - 5)) {
 		skb = dev_alloc_skb(RX_SKB_SIZE + DMA_ALIGN);
 		if (!skb)
 			break;
-		mp->rx_ring_skbs++;
+		mp->rx_desc_count++;
 		unaligned = (u32)skb->data & (DMA_ALIGN - 1);
 		if (unaligned)
 			skb_reserve(skb, DMA_ALIGN - unaligned);
@@ -194,7 +194,7 @@ static void mv643xx_eth_rx_task(void *data)
 	 * If RX ring is empty of SKB, set a timer to try allocating
 	 * again in a later time .
 	 */
-	if ((mp->rx_ring_skbs == 0) && (mp->rx_timer_flag == 0)) {
+	if ((mp->rx_desc_count == 0) && (mp->rx_timer_flag == 0)) {
 		printk(KERN_INFO "%s: Rx ring is empty\n", dev->name);
 		/* After 100mSec */
 		mp->timeout.expires = jiffies + (HZ / 10);
@@ -394,7 +394,7 @@ static int mv643xx_eth_receive_queue(struct net_device *dev)
 #else
 	while (eth_port_receive(mp, &pkt_info) == ETH_OK) {
 #endif
-		mp->rx_ring_skbs--;
+		mp->rx_desc_count--;
 		received_packets++;
 
 		/* Update statistics. Note byte count includes 4 byte CRC count */
@@ -494,7 +494,7 @@ static irqreturn_t mv643xx_eth_int_handler(int irq, void *dev_id,
 		/* UDP change : We may need this */
 		if ((eth_int_cause_ext & 0x0000ffff) &&
 		    (mv643xx_eth_free_tx_queue(dev, eth_int_cause_ext) == 0) &&
-		    (mp->tx_ring_size > mp->tx_ring_skbs + MAX_DESCS_PER_SKB))
+		    (mp->tx_ring_size > mp->tx_desc_count + MAX_DESCS_PER_SKB))
 			netif_wake_queue(dev);
 #ifdef MV643XX_NAPI
 	} else {
@@ -778,7 +778,7 @@ static int mv643xx_eth_open(struct net_device *dev)
 	}
 
 	/* Allocate TX ring */
-	mp->tx_ring_skbs = 0;
+	mp->tx_desc_count = 0;
 	size = mp->tx_ring_size * sizeof(struct eth_tx_desc);
 	mp->tx_desc_area_size = size;
 
@@ -803,7 +803,7 @@ static int mv643xx_eth_open(struct net_device *dev)
 	ether_init_tx_desc_ring(mp);
 
 	/* Allocate RX ring */
-	mp->rx_ring_skbs = 0;
+	mp->rx_desc_count = 0;
 	size = mp->rx_ring_size * sizeof(struct eth_rx_desc);
 	mp->rx_desc_area_size = size;
 
@@ -880,17 +880,17 @@ static void mv643xx_eth_free_tx_rings(struct net_device *dev)
 	mv_write(MV643XX_ETH_TRANSMIT_QUEUE_COMMAND_REG(port_num), 0x0000ff00);
 
 	/* Free outstanding skb's on TX rings */
-	for (curr = 0; mp->tx_ring_skbs && curr < mp->tx_ring_size; curr++) {
+	for (curr = 0; mp->tx_desc_count && curr < mp->tx_ring_size; curr++) {
 		skb = mp->tx_skb[curr];
 		if (skb) {
-			mp->tx_ring_skbs -= skb_shinfo(skb)->nr_frags;
+			mp->tx_desc_count -= skb_shinfo(skb)->nr_frags;
 			dev_kfree_skb(skb);
-			mp->tx_ring_skbs--;
+			mp->tx_desc_count--;
 		}
 	}
-	if (mp->tx_ring_skbs)
+	if (mp->tx_desc_count)
 		printk("%s: Error on Tx descriptor free - could not free %d"
-				" descriptors\n", dev->name, mp->tx_ring_skbs);
+				" descriptors\n", dev->name, mp->tx_desc_count);
 
 	/* Free TX ring */
 	if (mp->tx_sram_size)
@@ -910,18 +910,18 @@ static void mv643xx_eth_free_rx_rings(struct net_device *dev)
 	mv_write(MV643XX_ETH_RECEIVE_QUEUE_COMMAND_REG(port_num), 0x0000ff00);
 
 	/* Free preallocated skb's on RX rings */
-	for (curr = 0; mp->rx_ring_skbs && curr < mp->rx_ring_size; curr++) {
+	for (curr = 0; mp->rx_desc_count && curr < mp->rx_ring_size; curr++) {
 		if (mp->rx_skb[curr]) {
 			dev_kfree_skb(mp->rx_skb[curr]);
-			mp->rx_ring_skbs--;
+			mp->rx_desc_count--;
 		}
 	}
 
-	if (mp->rx_ring_skbs)
+	if (mp->rx_desc_count)
 		printk(KERN_ERR
 			"%s: Error in freeing Rx Ring. %d skb's still"
 			" stuck in RX Ring - ignoring them\n", dev->name,
-			mp->rx_ring_skbs);
+			mp->rx_desc_count);
 	/* Free RX ring */
 	if (mp->rx_sram_size)
 		iounmap(mp->p_rx_desc_area);
@@ -991,7 +991,8 @@ static void mv643xx_tx(struct net_device *dev)
 	}
 
 	if (netif_queue_stopped(dev) &&
-			mp->tx_ring_size > mp->tx_ring_skbs + MAX_DESCS_PER_SKB)
+			mp->tx_ring_size >
+					mp->tx_desc_count + MAX_DESCS_PER_SKB)
 		netif_wake_queue(dev);
 }
 
@@ -1083,7 +1084,7 @@ static int mv643xx_eth_start_xmit(struct sk_buff *skb, struct net_device *dev)
 	}
 
 	/* This is a hard error, log it. */
-	if ((mp->tx_ring_size - mp->tx_ring_skbs) <=
+	if ((mp->tx_ring_size - mp->tx_desc_count) <=
 					(skb_shinfo(skb)->nr_frags + 1)) {
 		netif_stop_queue(dev);
 		printk(KERN_ERR
@@ -1260,7 +1261,7 @@ static int mv643xx_eth_start_xmit(struct sk_buff *skb, struct net_device *dev)
 	/* Check if TX queue can handle another skb. If not, then
 	 * signal higher layers to stop requesting TX
 	 */
-	if (mp->tx_ring_size <= (mp->tx_ring_skbs + MAX_DESCS_PER_SKB))
+	if (mp->tx_ring_size <= (mp->tx_desc_count + MAX_DESCS_PER_SKB))
 		/*
 		 * Stop getting skb's from upper layers.
 		 * Getting skb's from upper layers will be enabled again after
@@ -2563,8 +2564,8 @@ static ETH_FUNC_RET_STATUS eth_port_send(struct mv643xx_private *mp,
 		return ETH_ERROR;
 	}
 
-	mp->tx_ring_skbs++;
-	BUG_ON(mp->tx_ring_skbs > mp->tx_ring_size);
+	mp->tx_desc_count++;
+	BUG_ON(mp->tx_desc_count > mp->tx_ring_size);
 
 	/* Get the Tx Desc ring indexes */
 	tx_desc_curr = mp->tx_curr_desc_q;
@@ -2632,8 +2633,8 @@ static ETH_FUNC_RET_STATUS eth_port_send(struct mv643xx_private *mp,
 	if (mp->tx_resource_err)
 		return ETH_QUEUE_FULL;
 
-	mp->tx_ring_skbs++;
-	BUG_ON(mp->tx_ring_skbs > mp->tx_ring_size);
+	mp->tx_desc_count++;
+	BUG_ON(mp->tx_desc_count > mp->tx_ring_size);
 
 	/* Get the Tx Desc ring indexes */
 	tx_desc_curr = mp->tx_curr_desc_q;
@@ -2747,8 +2748,8 @@ static ETH_FUNC_RET_STATUS eth_tx_return_desc(struct mv643xx_private *mp,
 	/* Any Tx return cancels the Tx resource error status */
 	mp->tx_resource_err = 0;
 
-	BUG_ON(mp->tx_ring_skbs == 0);
-	mp->tx_ring_skbs--;
+	BUG_ON(mp->tx_desc_count == 0);
+	mp->tx_desc_count--;
 
 out:
 	spin_unlock_irqrestore(&mp->lock, flags);

drivers/net/mv643xx_eth.h

@@ -371,12 +371,12 @@ struct mv643xx_private {
 	spinlock_t lock;
 	/* Size of Tx Ring per queue */
 	unsigned int tx_ring_size;
-	/* Ammont of SKBs outstanding on Tx queue */
-	unsigned int tx_ring_skbs;
+	/* Number of tx descriptors in use */
+	unsigned int tx_desc_count;
 	/* Size of Rx Ring per queue */
 	unsigned int rx_ring_size;
-	/* Ammount of SKBs allocated to Rx Ring per queue */
-	unsigned int rx_ring_skbs;
+	/* Number of rx descriptors in use */
+	unsigned int rx_desc_count;
 
 	/*
 	 * rx_task used to fill RX ring out of bottom half context