ixgbe: fix default setting of TXDCTL.WTHRESH

The q_vector->itr check in ixgbe_configure_tx_ring() was done prior to it
being set, which resulted in TXDCTL.WTHRESH always being set to 1 on driver
load, while consequent resets would set it to 8.

This patch moves the setting of q_vector->itr in ixgbe_alloc_q_vector() to
make sure that TXDCTL.WTHRESH is set to 8 by default.

Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/ixgbe/ixgbe_lib.c

@@ -824,6 +824,21 @@ static int ixgbe_alloc_q_vector(struct ixgbe_adapter *adapter,
 	/* initialize pointer to rings */
 	ring = q_vector->ring;
 
+	/* intialize ITR */
+	if (txr_count && !rxr_count) {
+		/* tx only vector */
+		if (adapter->tx_itr_setting == 1)
+			q_vector->itr = IXGBE_10K_ITR;
+		else
+			q_vector->itr = adapter->tx_itr_setting;
+	} else {
+		/* rx or rx/tx vector */
+		if (adapter->rx_itr_setting == 1)
+			q_vector->itr = IXGBE_20K_ITR;
+		else
+			q_vector->itr = adapter->rx_itr_setting;
+	}
+
 	while (txr_count) {
 		/* assign generic ring traits */
 		ring->dev = &adapter->pdev->dev;

drivers/net/ethernet/intel/ixgbe/ixgbe_main.c

@@ -1976,20 +1976,6 @@ static void ixgbe_configure_msix(struct ixgbe_adapter *adapter)
 		ixgbe_for_each_ring(ring, q_vector->tx)
 			ixgbe_set_ivar(adapter, 1, ring->reg_idx, v_idx);
 
-		if (q_vector->tx.ring && !q_vector->rx.ring) {
-			/* tx only vector */
-			if (adapter->tx_itr_setting == 1)
-				q_vector->itr = IXGBE_10K_ITR;
-			else
-				q_vector->itr = adapter->tx_itr_setting;
-		} else {
-			/* rx or rx/tx vector */
-			if (adapter->rx_itr_setting == 1)
-				q_vector->itr = IXGBE_20K_ITR;
-			else
-				q_vector->itr = adapter->rx_itr_setting;
-		}
-
 		ixgbe_write_eitr(q_vector);
 	}
 
@@ -2761,12 +2747,6 @@ static void ixgbe_configure_msi_and_legacy(struct ixgbe_adapter *adapter)
 {
 	struct ixgbe_q_vector *q_vector = adapter->q_vector[0];
 
-	/* rx/tx vector */
-	if (adapter->rx_itr_setting == 1)
-		q_vector->itr = IXGBE_20K_ITR;
-	else
-		q_vector->itr = adapter->rx_itr_setting;
-
 	ixgbe_write_eitr(q_vector);
 
 	ixgbe_set_ivar(adapter, 0, 0, 0);