[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>

1 files changed, 19 insertions, 9 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index 9d153eb1e8c..a3ed53cc4af 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1009,13 +1009,22 @@ void net_disable_timestamp(void)
         atomic_dec(&netstamp_needed);
 }
 
-static inline void net_timestamp(struct timeval *stamp)
+void __net_timestamp(struct sk_buff *skb)
+{
+        struct timeval tv;
+
+        do_gettimeofday(&tv);
+        skb_set_timestamp(skb, &tv);
+}
+EXPORT_SYMBOL(__net_timestamp);
+
+static inline void net_timestamp(struct sk_buff *skb)
 {
         if (atomic_read(&netstamp_needed))
-                do_gettimeofday(stamp);
+                __net_timestamp(skb);
         else {
-                stamp->tv_sec = 0;
-                stamp->tv_usec = 0;
+                skb->tstamp.off_sec = 0;
+                skb->tstamp.off_usec = 0;
         }
 }
 
@@ -1027,7 +1036,8 @@ static inline void net_timestamp(struct timeval *stamp)
 void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
 {
         struct packet_type *ptype;
-        net_timestamp(&skb->stamp);
+
+        net_timestamp(skb);
 
         rcu_read_lock();
         list_for_each_entry_rcu(ptype, &ptype_all, list) {
@@ -1379,8 +1389,8 @@ int netif_rx(struct sk_buff *skb)
         if (netpoll_rx(skb))
                 return NET_RX_DROP;
 
-        if (!skb->stamp.tv_sec)
-                net_timestamp(&skb->stamp);
+        if (!skb->tstamp.off_sec)
+                net_timestamp(skb);
 
         /*
          * The code is rearranged so that the path is the most
@@ -1566,8 +1576,8 @@ int netif_receive_skb(struct sk_buff *skb)
         if (skb->dev->poll && netpoll_rx(skb))
                 return NET_RX_DROP;
 
-        if (!skb->stamp.tv_sec)
-                net_timestamp(&skb->stamp);
+        if (!skb->tstamp.off_sec)
+                net_timestamp(skb);
 
         if (!skb->input_dev)
                 skb->input_dev = skb->dev;