i40e/i40evf: enable prefetch of Tx descriptors during cleanup

Performance can be improved a bit by imitating ixgbe and using
prefetch to get us the next Tx descriptor.

Change-ID: Ice7ffd4cd0ce87c35295059bdb7972a7f53723aa
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/net/ethernet/intel/i40evf/i40e_txrx.c b/drivers/net/ethernet/intel/i40evf/i40e_txrx.c
index 1c2637b28728..d9f3db542c5f 100644
--- a/drivers/net/ethernet/intel/i40evf/i40e_txrx.c
+++ b/drivers/net/ethernet/intel/i40evf/i40e_txrx.c
@@ -289,6 +289,8 @@ static bool i40e_clean_tx_irq(struct i40e_ring *tx_ring, int budget)
                         tx_desc = I40E_TX_DESC(tx_ring, 0);
                 }
 
+                prefetch(tx_desc);
+
                 /* update budget accounting */
                 budget--;
         } while (likely(budget));