i40e/i40evf: improve Tx performance with a small tweak
Add a prefetch for the next Tx descriptor to be used when we know
there are more coming.
Change-ID: Ibb9acab11d508eec2db7da795df74debc16eeacb
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: Jim Young <james.m.young@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
diff --git a/drivers/net/ethernet/intel/i40evf/i40e_txrx.c b/drivers/net/ethernet/intel/i40evf/i40e_txrx.c
index 395f32f..0f0e185 100644
--- a/drivers/net/ethernet/intel/i40evf/i40e_txrx.c
+++ b/drivers/net/ethernet/intel/i40evf/i40e_txrx.c
@@ -1841,6 +1841,8 @@
netif_xmit_stopped(netdev_get_tx_queue(tx_ring->netdev,
tx_ring->queue_index)))
writel(i, tx_ring->tail);
+ else
+ prefetchw(tx_desc + 1);
return;