forcedeth: remove unneeded stats updates

Function ndo_get_stats() updates most of the stats from hardware
registers, making the manual updates un-needed. This change removes
these manual updates. Main exception is rx_missed_errors which needs
manual update.

Another exception is rx_packets, still updated manually in this commit
to make sure this patch doesn't change behavior of driver. This will
be addressed by a future patch.
Signed-off-by: David Decotigny <david.decotigny@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/nvidia/forcedeth.c

@@ -2374,16 +2374,8 @@ static int nv_tx_done(struct net_device *dev, int limit)
 		if (np->desc_ver == DESC_VER_1) {
 			if (flags & NV_TX_LASTPACKET) {
 				if (flags & NV_TX_ERROR) {
-					if (flags & NV_TX_UNDERFLOW)
-						dev->stats.tx_fifo_errors++;
-					if (flags & NV_TX_CARRIERLOST)
-						dev->stats.tx_carrier_errors++;
 					if ((flags & NV_TX_RETRYERROR) && !(flags & NV_TX_RETRYCOUNT_MASK))
 						nv_legacybackoff_reseed(dev);
-					dev->stats.tx_errors++;
-				} else {
-					dev->stats.tx_packets++;
-					dev->stats.tx_bytes += np->get_tx_ctx->skb->len;
 				}
 				dev_kfree_skb_any(np->get_tx_ctx->skb);
 				np->get_tx_ctx->skb = NULL;
@@ -2392,16 +2384,8 @@ static int nv_tx_done(struct net_device *dev, int limit)
 		} else {
 			if (flags & NV_TX2_LASTPACKET) {
 				if (flags & NV_TX2_ERROR) {
-					if (flags & NV_TX2_UNDERFLOW)
-						dev->stats.tx_fifo_errors++;
-					if (flags & NV_TX2_CARRIERLOST)
-						dev->stats.tx_carrier_errors++;
 					if ((flags & NV_TX2_RETRYERROR) && !(flags & NV_TX2_RETRYCOUNT_MASK))
 						nv_legacybackoff_reseed(dev);
-					dev->stats.tx_errors++;
-				} else {
-					dev->stats.tx_packets++;
-					dev->stats.tx_bytes += np->get_tx_ctx->skb->len;
 				}
 				dev_kfree_skb_any(np->get_tx_ctx->skb);
 				np->get_tx_ctx->skb = NULL;
@@ -2434,9 +2418,7 @@ static int nv_tx_done_optimized(struct net_device *dev, int limit)
 		nv_unmap_txskb(np, np->get_tx_ctx);
 
 		if (flags & NV_TX2_LASTPACKET) {
-			if (!(flags & NV_TX2_ERROR))
-				dev->stats.tx_packets++;
-			else {
+			if (flags & NV_TX2_ERROR) {
 				if ((flags & NV_TX2_RETRYERROR) && !(flags & NV_TX2_RETRYCOUNT_MASK)) {
 					if (np->driver_data & DEV_HAS_GEAR_MODE)
 						nv_gear_backoff_reseed(dev);
@@ -2636,7 +2618,6 @@ static int nv_rx_process(struct net_device *dev, int limit)
 					if ((flags & NV_RX_ERROR_MASK) == NV_RX_ERROR4) {
 						len = nv_getlen(dev, skb->data, len);
 						if (len < 0) {
-							dev->stats.rx_errors++;
 							dev_kfree_skb(skb);
 							goto next_pkt;
 						}
@@ -2650,11 +2631,6 @@ static int nv_rx_process(struct net_device *dev, int limit)
 					else {
 						if (flags & NV_RX_MISSEDFRAME)
 							dev->stats.rx_missed_errors++;
-						if (flags & NV_RX_CRCERR)
-							dev->stats.rx_crc_errors++;
-						if (flags & NV_RX_OVERFLOW)
-							dev->stats.rx_over_errors++;
-						dev->stats.rx_errors++;
 						dev_kfree_skb(skb);
 						goto next_pkt;
 					}
@@ -2670,7 +2646,6 @@ static int nv_rx_process(struct net_device *dev, int limit)
 					if ((flags & NV_RX2_ERROR_MASK) == NV_RX2_ERROR4) {
 						len = nv_getlen(dev, skb->data, len);
 						if (len < 0) {
-							dev->stats.rx_errors++;
 							dev_kfree_skb(skb);
 							goto next_pkt;
 						}
@@ -2682,11 +2657,6 @@ static int nv_rx_process(struct net_device *dev, int limit)
 					}
 					/* the rest are hard errors */
 					else {
-						if (flags & NV_RX2_CRCERR)
-							dev->stats.rx_crc_errors++;
-						if (flags & NV_RX2_OVERFLOW)
-							dev->stats.rx_over_errors++;
-						dev->stats.rx_errors++;
 						dev_kfree_skb(skb);
 						goto next_pkt;
 					}
@@ -2704,7 +2674,6 @@ static int nv_rx_process(struct net_device *dev, int limit)
 		skb->protocol = eth_type_trans(skb, dev);
 		napi_gro_receive(&np->napi, skb);
 		dev->stats.rx_packets++;
-		dev->stats.rx_bytes += len;
 next_pkt:
 		if (unlikely(np->get_rx.orig++ == np->last_rx.orig))
 			np->get_rx.orig = np->first_rx.orig;
@@ -2787,9 +2756,7 @@ static int nv_rx_process_optimized(struct net_device *dev, int limit)
 				__vlan_hwaccel_put_tag(skb, vid);
 			}
 			napi_gro_receive(&np->napi, skb);
-
 			dev->stats.rx_packets++;
-			dev->stats.rx_bytes += len;
 		} else {
 			dev_kfree_skb(skb);
 		}