[NET]: Store skb->timestamp as offset to a base timestamp

Reduces skb size by 8 bytes on 64-bit.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 62 insertions, 9 deletions

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 60b32151f76..32635c401d4 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -155,13 +155,20 @@ struct skb_shared_info {
 #define SKB_DATAREF_SHIFT 16
 #define SKB_DATAREF_MASK ((1 << SKB_DATAREF_SHIFT) - 1)
 
+extern struct timeval skb_tv_base;
+
+struct skb_timeval {
+	u32	off_sec;
+	u32	off_usec;
+};
+
 /** 
  *	struct sk_buff - socket buffer
  *	@next: Next buffer in list
  *	@prev: Previous buffer in list
  *	@list: List we are on
  *	@sk: Socket we are owned by
- *	@stamp: Time we arrived
+ *	@tstamp: Time we arrived stored as offset to skb_tv_base
  *	@dev: Device we arrived on/are leaving by
  *	@input_dev: Device we arrived on
  *	@h: Transport layer header
@@ -202,7 +209,7 @@ struct sk_buff {
 	struct sk_buff		*prev;
 
 	struct sock		*sk;
-	struct timeval		stamp;
+	struct skb_timeval	tstamp;
 	struct net_device	*dev;
 	struct net_device	*input_dev;
 
@@ -1213,6 +1220,42 @@ static inline void *skb_header_pointer(const struct sk_buff *skb, int offset,
 extern void skb_init(void);
 extern void skb_add_mtu(int mtu);
 
+/**
+ *	skb_get_timestamp - get timestamp from a skb
+ *	@skb: skb to get stamp from
+ *	@stamp: pointer to struct timeval to store stamp in
+ *
+ *	Timestamps are stored in the skb as offsets to a base timestamp.
+ *	This function converts the offset back to a struct timeval and stores
+ *	it in stamp.
+ */
+static inline void skb_get_timestamp(struct sk_buff *skb, struct timeval *stamp)
+{
+	stamp->tv_sec  = skb->tstamp.off_sec;
+	stamp->tv_usec = skb->tstamp.off_usec;
+	if (skb->tstamp.off_sec) {
+		stamp->tv_sec  += skb_tv_base.tv_sec;
+		stamp->tv_usec += skb_tv_base.tv_usec;
+	}
+}
+
+/**
+ * 	skb_set_timestamp - set timestamp of a skb
+ *	@skb: skb to set stamp of
+ *	@stamp: pointer to struct timeval to get stamp from
+ *
+ *	Timestamps are stored in the skb as offsets to a base timestamp.
+ *	This function converts a struct timeval to an offset and stores
+ *	it in the skb.
+ */
+static inline void skb_set_timestamp(struct sk_buff *skb, struct timeval *stamp)
+{
+	skb->tstamp.off_sec  = stamp->tv_sec - skb_tv_base.tv_sec;
+	skb->tstamp.off_usec = stamp->tv_usec - skb_tv_base.tv_usec;
+}
+
+extern void __net_timestamp(struct sk_buff *skb);
+
 #ifdef CONFIG_NETFILTER
 static inline void nf_conntrack_put(struct nf_conntrack *nfct)
 {
diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index 6d63a47c731..7f933f30207 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -404,7 +404,7 @@ static inline int hci_recv_frame(struct sk_buff *skb)
 	bt_cb(skb)->incoming = 1;
 
 	/* Time stamp */
-	do_gettimeofday(&skb->stamp);
+	__net_timestamp(skb);
 
 	/* Queue frame for rx task */
 	skb_queue_tail(&hdev->rx_q, skb);
diff --git a/include/net/neighbour.h b/include/net/neighbour.h
index 89809891e5a..34c07731933 100644
--- a/include/net/neighbour.h
+++ b/include/net/neighbour.h
@@ -363,7 +363,14 @@ __neigh_lookup_errno(struct neigh_table *tbl, const void *pkey,
 	return neigh_create(tbl, pkey, dev);
 }
 
-#define LOCALLY_ENQUEUED -2
+struct neighbour_cb {
+	unsigned long sched_next;
+	unsigned int flags;
+};
+
+#define LOCALLY_ENQUEUED 0x1
+
+#define NEIGH_CB(skb)	((struct neighbour_cb *)(skb)->cb)
 
 #endif
 #endif
diff --git a/include/net/sock.h b/include/net/sock.h
index 065df67b642..d5942887707 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -1282,16 +1282,19 @@ static inline int sock_intr_errno(long timeo)
 static __inline__ void
 sock_recv_timestamp(struct msghdr *msg, struct sock *sk, struct sk_buff *skb)
 {
-	struct timeval *stamp = &skb->stamp;
+	struct timeval stamp;
+
+	skb_get_timestamp(skb, &stamp);
 	if (sock_flag(sk, SOCK_RCVTSTAMP)) {
 		/* Race occurred between timestamp enabling and packet
 		   receiving.  Fill in the current time for now. */
-		if (stamp->tv_sec == 0)
-			do_gettimeofday(stamp);
+		if (stamp.tv_sec == 0)
+			do_gettimeofday(&stamp);
+		skb_set_timestamp(skb, &stamp);
 		put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMP, sizeof(struct timeval),
-			 stamp);
+			 &stamp);
 	} else
-		sk->sk_stamp = *stamp;
+		sk->sk_stamp = stamp;
 }
 
 /**