[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>
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 60b3215..32635c4 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -155,13 +155,20 @@
#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 *prev;
struct sock *sk;
- struct timeval stamp;
+ struct skb_timeval tstamp;
struct net_device *dev;
struct net_device *input_dev;
@@ -1213,6 +1220,42 @@
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)
{