net: Use sk_tx_queue_mapping for connected sockets

For connected sockets, the first run of dev_pick_tx saves the
calculated txq in sk_tx_queue_mapping. This is not saved if
either the device has a queue select or the socket is not
connected. Next iterations of dev_pick_tx uses the cached value
of sk_tx_queue_mapping.

Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 18 insertions, 6 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index 28b0b9e992a0..fa88dcd476d6 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1791,13 +1791,25 @@ EXPORT_SYMBOL(skb_tx_hash);
 static struct netdev_queue *dev_pick_tx(struct net_device *dev,
                                         struct sk_buff *skb)
 {
-        const struct net_device_ops *ops = dev->netdev_ops;
-        u16 queue_index = 0;
+        u16 queue_index;
+        struct sock *sk = skb->sk;
+
+        if (sk_tx_queue_recorded(sk)) {
+                queue_index = sk_tx_queue_get(sk);
+        } else {
+                const struct net_device_ops *ops = dev->netdev_ops;
 
-        if (ops->ndo_select_queue)
-                queue_index = ops->ndo_select_queue(dev, skb);
-        else if (dev->real_num_tx_queues > 1)
-                queue_index = skb_tx_hash(dev, skb);
+                if (ops->ndo_select_queue) {
+                        queue_index = ops->ndo_select_queue(dev, skb);
+                } else {
+                        queue_index = 0;
+                        if (dev->real_num_tx_queues > 1)
+                                queue_index = skb_tx_hash(dev, skb);
+
+                        if (sk && sk->sk_dst_cache)
+                                sk_tx_queue_set(sk, queue_index);
+                }
+        }
 
         skb_set_queue_mapping(skb, queue_index);
         return netdev_get_tx_queue(dev, queue_index);