3 files changed, 23 insertions, 7 deletions

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index d31bc3c94717..445e6825f8eb 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1747,6 +1747,16 @@ static inline void netif_wake_subqueue(struct net_device *dev, u16 queue_index)
                 __netif_schedule(txq->qdisc);
 }
 
+/*
+ * 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,
+                              const 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
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 19f37a6ee6c4..4c4bec6316d9 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -2165,8 +2165,9 @@ static inline bool skb_rx_queue_recorded(const struct sk_buff *skb)
         return skb->queue_mapping != 0;
 }
 
-extern u16 skb_tx_hash(const struct net_device *dev,
-                       const struct sk_buff *skb);
+extern u16 __skb_tx_hash(const struct net_device *dev,
+                         const struct sk_buff *skb,
+                         unsigned int num_tx_queues);
 
 #ifdef CONFIG_XFRM
 static inline struct sec_path *skb_sec_path(struct sk_buff *skb)
diff --git a/net/core/dev.c b/net/core/dev.c
index d28b3a023bb2..b25dd087f06a 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -2112,14 +2112,19 @@ out:
 
 static u32 hashrnd __read_mostly;
 
-u16 skb_tx_hash(const struct net_device *dev, const struct sk_buff *skb)
+/*
+ * 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, const struct sk_buff *skb,
+                  unsigned int num_tx_queues)
 {
         u32 hash;
 
         if (skb_rx_queue_recorded(skb)) {
                 hash = skb_get_rx_queue(skb);
-                while (unlikely(hash >= dev->real_num_tx_queues))
-                        hash -= dev->real_num_tx_queues;
+                while (unlikely(hash >= num_tx_queues))
+                        hash -= num_tx_queues;
                 return hash;
         }
 
@@ -2129,9 +2134,9 @@ u16 skb_tx_hash(const struct net_device *dev, const struct sk_buff *skb)
                 hash = (__force u16) skb->protocol ^ skb->rxhash;
         hash = jhash_1word(hash, hashrnd);
 
-        return (u16) (((u64) hash * dev->real_num_tx_queues) >> 32);
+        return (u16) (((u64) hash * num_tx_queues) >> 32);
 }
-EXPORT_SYMBOL(skb_tx_hash);
+EXPORT_SYMBOL(__skb_tx_hash);
 
 static inline u16 dev_cap_txqueue(struct net_device *dev, u16 queue_index)
 {