ixgbe: Allow tx itr specific settings

Allow the user to set Tx specific itr values.  This only makes sense
when there are separate vectors for Tx and Rx.  When the queues are
doubled up RxTx on the vectors, we still only use the rx itr value.

Signed-off-by: Shannon Nelson <shannon.nelson@intel.com>
Acked-by: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ixgbe/ixgbe_ethtool.c b/drivers/net/ixgbe/ixgbe_ethtool.c
index 026e94a..53b0a66 100644
--- a/drivers/net/ixgbe/ixgbe_ethtool.c
+++ b/drivers/net/ixgbe/ixgbe_ethtool.c
@@ -1929,7 +1929,7 @@
 	ec->tx_max_coalesced_frames_irq = adapter->tx_ring[0].work_limit;
 
 	/* only valid if in constant ITR mode */
-	switch (adapter->itr_setting) {
+	switch (adapter->rx_itr_setting) {
 	case 0:
 		/* throttling disabled */
 		ec->rx_coalesce_usecs = 0;
@@ -1940,9 +1940,25 @@
 		break;
 	default:
 		/* fixed interrupt rate mode */
-		ec->rx_coalesce_usecs = 1000000/adapter->eitr_param;
+		ec->rx_coalesce_usecs = 1000000/adapter->rx_eitr_param;
 		break;
 	}
+
+	/* only valid if in constant ITR mode */
+	switch (adapter->tx_itr_setting) {
+	case 0:
+		/* throttling disabled */
+		ec->tx_coalesce_usecs = 0;
+		break;
+	case 1:
+		/* dynamic ITR mode */
+		ec->tx_coalesce_usecs = 1;
+		break;
+	default:
+		ec->tx_coalesce_usecs = 1000000/adapter->tx_eitr_param;
+		break;
+	}
+
 	return 0;
 }
 
@@ -1953,6 +1969,14 @@
 	struct ixgbe_q_vector *q_vector;
 	int i;
 
+	/*
+	 * don't accept tx specific changes if we've got mixed RxTx vectors
+	 * test and jump out here if needed before changing the rx numbers
+	 */
+	if ((1000000/ec->tx_coalesce_usecs) != adapter->tx_eitr_param &&
+	    adapter->q_vector[0]->txr_count && adapter->q_vector[0]->rxr_count)
+		return -EINVAL;
+
 	if (ec->tx_max_coalesced_frames_irq)
 		adapter->tx_ring[0].work_limit = ec->tx_max_coalesced_frames_irq;
 
@@ -1963,26 +1987,49 @@
 			return -EINVAL;
 
 		/* store the value in ints/second */
-		adapter->eitr_param = 1000000/ec->rx_coalesce_usecs;
+		adapter->rx_eitr_param = 1000000/ec->rx_coalesce_usecs;
 
 		/* static value of interrupt rate */
-		adapter->itr_setting = adapter->eitr_param;
+		adapter->rx_itr_setting = adapter->rx_eitr_param;
 		/* clear the lower bit as its used for dynamic state */
-		adapter->itr_setting &= ~1;
+		adapter->rx_itr_setting &= ~1;
 	} else if (ec->rx_coalesce_usecs == 1) {
 		/* 1 means dynamic mode */
-		adapter->eitr_param = 20000;
-		adapter->itr_setting = 1;
+		adapter->rx_eitr_param = 20000;
+		adapter->rx_itr_setting = 1;
 	} else {
 		/*
 		 * any other value means disable eitr, which is best
 		 * served by setting the interrupt rate very high
 		 */
 		if (adapter->flags2 & IXGBE_FLAG2_RSC_ENABLED)
-			adapter->eitr_param = IXGBE_MAX_RSC_INT_RATE;
+			adapter->rx_eitr_param = IXGBE_MAX_RSC_INT_RATE;
 		else
-			adapter->eitr_param = IXGBE_MAX_INT_RATE;
-		adapter->itr_setting = 0;
+			adapter->rx_eitr_param = IXGBE_MAX_INT_RATE;
+		adapter->rx_itr_setting = 0;
+	}
+
+	if (ec->tx_coalesce_usecs > 1) {
+		/* check the limits */
+		if ((1000000/ec->tx_coalesce_usecs > IXGBE_MAX_INT_RATE) ||
+		    (1000000/ec->tx_coalesce_usecs < IXGBE_MIN_INT_RATE))
+			return -EINVAL;
+
+		/* store the value in ints/second */
+		adapter->tx_eitr_param = 1000000/ec->tx_coalesce_usecs;
+
+		/* static value of interrupt rate */
+		adapter->tx_itr_setting = adapter->tx_eitr_param;
+
+		/* clear the lower bit as its used for dynamic state */
+		adapter->tx_itr_setting &= ~1;
+	} else if (ec->tx_coalesce_usecs == 1) {
+		/* 1 means dynamic mode */
+		adapter->tx_eitr_param = 10000;
+		adapter->tx_itr_setting = 1;
+	} else {
+		adapter->tx_eitr_param = IXGBE_MAX_INT_RATE;
+		adapter->tx_itr_setting = 0;
 	}
 
 	/* MSI/MSIx Interrupt Mode */
@@ -1992,17 +2039,17 @@
 		for (i = 0; i < num_vectors; i++) {
 			q_vector = adapter->q_vector[i];
 			if (q_vector->txr_count && !q_vector->rxr_count)
-				/* tx vector gets half the rate */
-				q_vector->eitr = (adapter->eitr_param >> 1);
+				/* tx only */
+				q_vector->eitr = adapter->tx_eitr_param;
 			else
 				/* rx only or mixed */
-				q_vector->eitr = adapter->eitr_param;
+				q_vector->eitr = adapter->rx_eitr_param;
 			ixgbe_write_eitr(q_vector);
 		}
 	/* Legacy Interrupt Mode */
 	} else {
 		q_vector = adapter->q_vector[0];
-		q_vector->eitr = adapter->eitr_param;
+		q_vector->eitr = adapter->rx_eitr_param;
 		ixgbe_write_eitr(q_vector);
 	}