2 files changed, 30 insertions, 54 deletions

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 950dc55e519..40ccf8cc423 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -598,20 +598,7 @@ DECLARE_PER_CPU(struct softnet_data,softnet_data);
 
 #define HAVE_NETIF_QUEUE
 
-static inline void __netif_schedule(struct net_device *dev)
-{
-	if (!test_and_set_bit(__LINK_STATE_SCHED, &dev->state)) {
-		unsigned long flags;
-		struct softnet_data *sd;
-
-		local_irq_save(flags);
-		sd = &__get_cpu_var(softnet_data);
-		dev->next_sched = sd->output_queue;
-		sd->output_queue = dev;
-		raise_softirq_irqoff(NET_TX_SOFTIRQ);
-		local_irq_restore(flags);
-	}
-}
+extern void __netif_schedule(struct net_device *dev);
 
 static inline void netif_schedule(struct net_device *dev)
 {
@@ -675,13 +662,7 @@ static inline void dev_kfree_skb_irq(struct sk_buff *skb)
 /* Use this variant in places where it could be invoked
  * either from interrupt or non-interrupt context.
  */
-static inline void dev_kfree_skb_any(struct sk_buff *skb)
-{
-	if (in_irq() || irqs_disabled())
-		dev_kfree_skb_irq(skb);
-	else
-		dev_kfree_skb(skb);
-}
+extern void dev_kfree_skb_any(struct sk_buff *skb);
 
 #define HAVE_NETIF_RX 1
 extern int		netif_rx(struct sk_buff *skb);
@@ -768,22 +749,9 @@ static inline int netif_device_present(struct net_device *dev)
 	return test_bit(__LINK_STATE_PRESENT, &dev->state);
 }
 
-static inline void netif_device_detach(struct net_device *dev)
-{
-	if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) &&
-	    netif_running(dev)) {
-		netif_stop_queue(dev);
-	}
-}
+extern void netif_device_detach(struct net_device *dev);
 
-static inline void netif_device_attach(struct net_device *dev)
-{
-	if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) &&
-	    netif_running(dev)) {
-		netif_wake_queue(dev);
- 		__netdev_watchdog_up(dev);
-	}
-}
+extern void netif_device_attach(struct net_device *dev);
 
 /*
  * Network interface message level settings
@@ -851,20 +819,7 @@ static inline int netif_rx_schedule_prep(struct net_device *dev)
  * already been called and returned 1.
  */
 
-static inline void __netif_rx_schedule(struct net_device *dev)
-{
-	unsigned long flags;
-
-	local_irq_save(flags);
-	dev_hold(dev);
-	list_add_tail(&dev->poll_list, &__get_cpu_var(softnet_data).poll_list);
-	if (dev->quota < 0)
-		dev->quota += dev->weight;
-	else
-		dev->quota = dev->weight;
-	__raise_softirq_irqoff(NET_RX_SOFTIRQ);
-	local_irq_restore(flags);
-}
+extern void __netif_rx_schedule(struct net_device *dev);
 
 /* Try to reschedule poll. Called by irq handler. */
 
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 613b9513f8b..c4619a428d9 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -941,6 +941,25 @@ static inline void skb_reserve(struct sk_buff *skb, int len)
 #define NET_IP_ALIGN	2
 #endif
 
+/*
+ * The networking layer reserves some headroom in skb data (via
+ * dev_alloc_skb). This is used to avoid having to reallocate skb data when
+ * the header has to grow. In the default case, if the header has to grow
+ * 16 bytes or less we avoid the reallocation.
+ *
+ * Unfortunately this headroom changes the DMA alignment of the resulting
+ * network packet. As for NET_IP_ALIGN, this unaligned DMA is expensive
+ * on some architectures. An architecture can override this value,
+ * perhaps setting it to a cacheline in size (since that will maintain
+ * cacheline alignment of the DMA). It must be a power of 2.
+ *
+ * Various parts of the networking layer expect at least 16 bytes of
+ * headroom, you should not reduce this.
+ */
+#ifndef NET_SKB_PAD
+#define NET_SKB_PAD	16
+#endif
+
 extern int ___pskb_trim(struct sk_buff *skb, unsigned int len, int realloc);
 
 static inline void __skb_trim(struct sk_buff *skb, unsigned int len)
@@ -1030,9 +1049,9 @@ static inline void __skb_queue_purge(struct sk_buff_head *list)
 static inline struct sk_buff *__dev_alloc_skb(unsigned int length,
 					      gfp_t gfp_mask)
 {
-	struct sk_buff *skb = alloc_skb(length + 16, gfp_mask);
+	struct sk_buff *skb = alloc_skb(length + NET_SKB_PAD, gfp_mask);
 	if (likely(skb))
-		skb_reserve(skb, 16);
+		skb_reserve(skb, NET_SKB_PAD);
 	return skb;
 }
 #else
@@ -1070,13 +1089,15 @@ static inline struct sk_buff *dev_alloc_skb(unsigned int length)
  */
 static inline int skb_cow(struct sk_buff *skb, unsigned int headroom)
 {
-	int delta = (headroom > 16 ? headroom : 16) - skb_headroom(skb);
+	int delta = (headroom > NET_SKB_PAD ? headroom : NET_SKB_PAD) -
+			skb_headroom(skb);
 
 	if (delta < 0)
 		delta = 0;
 
 	if (delta || skb_cloned(skb))
-		return pskb_expand_head(skb, (delta + 15) & ~15, 0, GFP_ATOMIC);
+		return pskb_expand_head(skb, (delta + (NET_SKB_PAD-1)) &
+				~(NET_SKB_PAD-1), 0, GFP_ATOMIC);
 	return 0;
 }