net: Revoke export for __skb_tx_hash, update it to just be static skb_tx_hash

I am dropping the export of __skb_tx_hash as after my patches nobody is
using it outside of the net/core/dev.c file. In addition I am renaming and
repurposing it to just be a static declaration of skb_tx_hash since that
was the only user for it at this point. By doing this the compiler can
inline it into __netdev_pick_tx as that will improve performance.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/netdevice.h

@@ -3213,19 +3213,6 @@ static inline int netif_set_xps_queue(struct net_device *dev,
 }
 #endif
 
-u16 __skb_tx_hash(const struct net_device *dev, struct sk_buff *skb,
-		  unsigned int num_tx_queues);
-
-/*
- * Returns a Tx hash for the given packet when dev->real_num_tx_queues is used
- * as a distribution range limit for the returned value.
- */
-static inline u16 skb_tx_hash(const struct net_device *dev,
-			      struct sk_buff *skb)
-{
-	return __skb_tx_hash(dev, skb, dev->real_num_tx_queues);
-}
-
 /**
  *	netif_is_multiqueue - test if device has multiple transmit queues
  *	@dev: network device

net/core/dev.c

@@ -2615,17 +2615,16 @@ EXPORT_SYMBOL(netif_device_attach);
  * Returns a Tx hash based on the given packet descriptor a Tx queues' number
  * to be used as a distribution range.
  */
-u16 __skb_tx_hash(const struct net_device *dev, struct sk_buff *skb,
-		  unsigned int num_tx_queues)
+static u16 skb_tx_hash(const struct net_device *dev, struct sk_buff *skb)
 {
 	u32 hash;
 	u16 qoffset = 0;
-	u16 qcount = num_tx_queues;
+	u16 qcount = dev->real_num_tx_queues;
 
 	if (skb_rx_queue_recorded(skb)) {
 		hash = skb_get_rx_queue(skb);
-		while (unlikely(hash >= num_tx_queues))
-			hash -= num_tx_queues;
+		while (unlikely(hash >= qcount))
+			hash -= qcount;
 		return hash;
 	}
 
@@ -2638,7 +2637,6 @@ u16 __skb_tx_hash(const struct net_device *dev, struct sk_buff *skb,
 
 	return (u16) reciprocal_scale(skb_get_hash(skb), qcount) + qoffset;
 }
-EXPORT_SYMBOL(__skb_tx_hash);
 
 static void skb_warn_bad_offload(const struct sk_buff *skb)
 {