net: remove 'fallback' argument from dev->ndo_select_queue()

After the previous patch, all the callers of ndo_select_queue()
provide as a 'fallback' argument netdev_pick_tx.
The only exceptions are nested calls to ndo_select_queue(),
which pass down the 'fallback' available in the current scope
- still netdev_pick_tx.

We can drop such argument and replace fallback() invocation with
netdev_pick_tx(). This avoids an indirect call per xmit packet
in some scenarios (TCP syn, UDP unconnected, XDP generic, pktgen)
with device drivers implementing such ndo. It also clean the code
a bit.

Tested with ixgbe and CONFIG_FCOE=m

With pktgen using queue xmit:
threads		vanilla 	patched
		(kpps)		(kpps)
1		2334		2428
2		4166		4278
4		7895		8100

 v1 -> v2:
 - rebased after helper's name change

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 4 deletions

diff --git a/drivers/infiniband/ulp/opa_vnic/opa_vnic_netdev.c b/drivers/infiniband/ulp/opa_vnic/opa_vnic_netdev.c
index ae70cd18903e..aeff68f582d3 100644
--- a/drivers/infiniband/ulp/opa_vnic/opa_vnic_netdev.c
+++ b/drivers/infiniband/ulp/opa_vnic/opa_vnic_netdev.c
@@ -95,8 +95,7 @@ static netdev_tx_t opa_netdev_start_xmit(struct sk_buff *skb,
 }
 
 static u16 opa_vnic_select_queue(struct net_device *netdev, struct sk_buff *skb,
-                                 struct net_device *sb_dev,
-                                 select_queue_fallback_t fallback)
+                                 struct net_device *sb_dev)
 {
         struct opa_vnic_adapter *adapter = opa_vnic_priv(netdev);
         struct opa_vnic_skb_mdata *mdata;
@@ -106,8 +105,7 @@ static u16 opa_vnic_select_queue(struct net_device *netdev, struct sk_buff *skb,
         mdata = skb_push(skb, sizeof(*mdata));
         mdata->entropy = opa_vnic_calc_entropy(skb);
         mdata->vl = opa_vnic_get_vl(adapter, skb);
-        rc = adapter->rn_ops->ndo_select_queue(netdev, skb,
-                                               sb_dev, fallback);
+        rc = adapter->rn_ops->ndo_select_queue(netdev, skb, sb_dev);
         skb_pull(skb, sizeof(*mdata));
         return rc;
 }