qede - Add a statistic for a case where driver drops tx packet due to memory allocation failure.

skb_linearization can fail due to memory allocation failure.
In such a case, the driver will drop the packet. In such a case
The driver used to print an error message.
This patch replaces this error message by a dedicated statistic.
Signed-off-by: Michael Shteinbok <michael.shteinbok@cavium.com>
Signed-off-by: Ariel Elior <ariel.elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/qlogic/qede/qede.h

@@ -381,6 +381,7 @@ struct qede_tx_queue {
 
 	u64 xmit_pkts;
 	u64 stopped_cnt;
+	u64 tx_mem_alloc_err;
 
 	__le16 *hw_cons_ptr;
 

drivers/net/ethernet/qlogic/qede/qede_ethtool.c

@@ -73,6 +73,7 @@ static const struct {
 } qede_tqstats_arr[] = {
 	QEDE_TQSTAT(xmit_pkts),
 	QEDE_TQSTAT(stopped_cnt),
+	QEDE_TQSTAT(tx_mem_alloc_err),
 };
 
 #define QEDE_STAT_OFFSET(stat_name, type, base) \

drivers/net/ethernet/qlogic/qede/qede_fp.c

@@ -1466,8 +1466,8 @@ netdev_tx_t qede_start_xmit(struct sk_buff *skb, struct net_device *ndev)
 #if ((MAX_SKB_FRAGS + 2) > ETH_TX_MAX_BDS_PER_NON_LSO_PACKET)
 	if (qede_pkt_req_lin(skb, xmit_type)) {
 		if (skb_linearize(skb)) {
-			DP_NOTICE(edev,
-				  "SKB linearization failed - silently dropping this SKB\n");
+			txq->tx_mem_alloc_err++;
+
 			dev_kfree_skb_any(skb);
 			return NETDEV_TX_OK;
 		}