gianfar: Add support for byte queue limits.

Add support for byte queue limits (BQL), based on the similar
modifications made to intel/igb/igb_main.c from Eric Dumazet
in commit bdbc063129e811264cd6c311d8c2d9b95de01231
	"igb: Add support for byte queue limits."

A local variable for tx_queue->qindex was introduced in
gfar_clean_tx_ring, since it is now used often enough to warrant it,
and it cleans up the readability somewhat as well.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

1 files changed, 16 insertions, 3 deletions

diff --git a/drivers/net/ethernet/freescale/gianfar.c b/drivers/net/ethernet/freescale/gianfar.c
index adb0ae4e419..a4c934bbea1 100644
--- a/drivers/net/ethernet/freescale/gianfar.c
+++ b/drivers/net/ethernet/freescale/gianfar.c
@@ -1755,9 +1755,12 @@ static void free_skb_resources(struct gfar_private *priv)
 
         /* Go through all the buffer descriptors and free their data buffers */
         for (i = 0; i < priv->num_tx_queues; i++) {
+                struct netdev_queue *txq;
                 tx_queue = priv->tx_queue[i];
+                txq = netdev_get_tx_queue(tx_queue->dev, tx_queue->qindex);
                 if(tx_queue->tx_skbuff)
                         free_skb_tx_queue(tx_queue);
+                netdev_tx_reset_queue(txq);
         }
 
         for (i = 0; i < priv->num_rx_queues; i++) {
@@ -2217,6 +2220,8 @@ static int gfar_start_xmit(struct sk_buff *skb, struct net_device *dev)
                 lstatus |= BD_LFLAG(TXBD_CRC | TXBD_READY) | skb_headlen(skb);
         }
 
+        netdev_tx_sent_queue(txq, skb->len);
+
         /*
          * We can work in parallel with gfar_clean_tx_ring(), except
          * when modifying num_txbdfree. Note that we didn't grab the lock
@@ -2460,6 +2465,7 @@ static void gfar_align_skb(struct sk_buff *skb)
 static int gfar_clean_tx_ring(struct gfar_priv_tx_q *tx_queue)
 {
         struct net_device *dev = tx_queue->dev;
+        struct netdev_queue *txq;
         struct gfar_private *priv = netdev_priv(dev);
         struct gfar_priv_rx_q *rx_queue = NULL;
         struct txbd8 *bdp, *next = NULL;
@@ -2471,10 +2477,13 @@ static int gfar_clean_tx_ring(struct gfar_priv_tx_q *tx_queue)
         int frags = 0, nr_txbds = 0;
         int i;
         int howmany = 0;
+        int tqi = tx_queue->qindex;
+        unsigned int bytes_sent = 0;
         u32 lstatus;
         size_t buflen;
 
-        rx_queue = priv->rx_queue[tx_queue->qindex];
+        rx_queue = priv->rx_queue[tqi];
+        txq = netdev_get_tx_queue(dev, tqi);
         bdp = tx_queue->dirty_tx;
         skb_dirtytx = tx_queue->skb_dirtytx;
 
@@ -2533,6 +2542,8 @@ static int gfar_clean_tx_ring(struct gfar_priv_tx_q *tx_queue)
                         bdp = next_txbd(bdp, base, tx_ring_size);
                 }
 
+                bytes_sent += skb->len;
+
                 /*
                  * If there's room in the queue (limit it to rx_buffer_size)
                  * we add this skb back into the pool, if it's the right size
@@ -2557,13 +2568,15 @@ static int gfar_clean_tx_ring(struct gfar_priv_tx_q *tx_queue)
         }
 
         /* If we freed a buffer, we can restart transmission, if necessary */
-        if (__netif_subqueue_stopped(dev, tx_queue->qindex) && tx_queue->num_txbdfree)
-                netif_wake_subqueue(dev, tx_queue->qindex);
+        if (__netif_subqueue_stopped(dev, tqi) && tx_queue->num_txbdfree)
+                netif_wake_subqueue(dev, tqi);
 
         /* Update dirty indicators */
         tx_queue->skb_dirtytx = skb_dirtytx;
         tx_queue->dirty_tx = bdp;
 
+        netdev_tx_completed_queue(txq, howmany, bytes_sent);
+
         return howmany;
 }