packet: tx timestamping on tpacket ring
When transmit timestamping is enabled at the socket level, record a
timestamp on packets written to a PACKET_TX_RING. Tx timestamps are
always looped to the application over the socket error queue. Software
timestamps are also written back into the packet frame header in the
packet ring.
Reported-by: Paul Chavent <paul.chavent@onera.fr>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 898cf5c..af9185d 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -3327,12 +3327,8 @@
if (!sk)
return;
- skb = skb_clone(orig_skb, GFP_ATOMIC);
- if (!skb)
- return;
-
if (hwtstamps) {
- *skb_hwtstamps(skb) =
+ *skb_hwtstamps(orig_skb) =
*hwtstamps;
} else {
/*
@@ -3340,9 +3336,13 @@
* so keep the shared tx_flags and only
* store software time stamp
*/
- skb->tstamp = ktime_get_real();
+ orig_skb->tstamp = ktime_get_real();
}
+ skb = skb_clone(orig_skb, GFP_ATOMIC);
+ if (!skb)
+ return;
+
serr = SKB_EXT_ERR(skb);
memset(serr, 0, sizeof(*serr));
serr->ee.ee_errno = ENOMSG;