gianfar: Add support for skb recycling

Signed-off-by: Andy Fleming <afleming@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 21 insertions, 4 deletions

diff --git a/drivers/net/gianfar.c b/drivers/net/gianfar.c
index bd21b6d5f13c..33de25602b32 100644
--- a/drivers/net/gianfar.c
+++ b/drivers/net/gianfar.c
@@ -1181,6 +1181,8 @@ static int gfar_enet_open(struct net_device *dev)
 
         napi_enable(&priv->napi);
 
+        skb_queue_head_init(&priv->rx_recycle);
+
         /* Initialize a bunch of registers */
         init_registers(dev);
 
@@ -1399,6 +1401,7 @@ static int gfar_close(struct net_device *dev)
 
         napi_disable(&priv->napi);
 
+        skb_queue_purge(&priv->rx_recycle);
         cancel_work_sync(&priv->reset_task);
         stop_gfar(dev);
 
@@ -1595,7 +1598,17 @@ static int gfar_clean_tx_ring(struct net_device *dev)
                         bdp = next_txbd(bdp, base, tx_ring_size);
                 }
 
-                dev_kfree_skb_any(skb);
+                /*
+                 * 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
+                 */
+                if (skb_queue_len(&priv->rx_recycle) < priv->rx_ring_size &&
+                                skb_recycle_check(skb, priv->rx_buffer_size +
+                                        RXBUF_ALIGNMENT))
+                        __skb_queue_head(&priv->rx_recycle, skb);
+                else
+                        dev_kfree_skb_any(skb);
+
                 priv->tx_skbuff[skb_dirtytx] = NULL;
 
                 skb_dirtytx = (skb_dirtytx + 1) &
@@ -1668,8 +1681,10 @@ struct sk_buff * gfar_new_skb(struct net_device *dev)
         struct gfar_private *priv = netdev_priv(dev);
         struct sk_buff *skb = NULL;
 
-        /* We have to allocate the skb, so keep trying till we succeed */
-        skb = netdev_alloc_skb(dev, priv->rx_buffer_size + RXBUF_ALIGNMENT);
+        skb = __skb_dequeue(&priv->rx_recycle);
+        if (!skb)
+                skb = netdev_alloc_skb(dev,
+                                priv->rx_buffer_size + RXBUF_ALIGNMENT);
 
         if (!skb)
                 return NULL;
@@ -1817,7 +1832,7 @@ int gfar_clean_rx_ring(struct net_device *dev, int rx_work_limit)
                         if (unlikely(!newskb))
                                 newskb = skb;
                         else if (skb)
-                                dev_kfree_skb_any(skb);
+                                __skb_queue_head(&priv->rx_recycle, skb);
                 } else {
                         /* Increment the number of packets */
                         dev->stats.rx_packets++;
diff --git a/drivers/net/gianfar.h b/drivers/net/gianfar.h
index 3cb901b2e240..811855bc4231 100644
--- a/drivers/net/gianfar.h
+++ b/drivers/net/gianfar.h
@@ -758,6 +758,8 @@ struct gfar_private {
         unsigned int rx_stash_size;
         unsigned int rx_stash_index;
 
+        struct sk_buff_head rx_recycle;
+
         struct vlan_group *vlgrp;
 
         /* Unprotected fields */