diff options
| author | Willem de Bruijn <willemb@google.com> | 2015-01-30 13:29:31 -0500 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2015-02-02 18:46:51 -0800 |
| commit | 49ca0d8bfaf3bc46d5eef60ce67b00eb195bd392 (patch) | |
| tree | d2f55a32923f6d91fcb2e0d0e0b6d2d4eb6f9abd /net/core | |
| parent | 9766e97af1b901ffbb36fcc648e50626d926bb24 (diff) | |
net-timestamp: no-payload option
Add timestamping option SOF_TIMESTAMPING_OPT_TSONLY. For transmit
timestamps, this loops timestamps on top of empty packets.
Doing so reduces the pressure on SO_RCVBUF. Payload inspection and
cmsg reception (aside from timestamps) are no longer possible. This
works together with a follow on patch that allows administrators to
only allow tx timestamping if it does not loop payload or metadata.
Signed-off-by: Willem de Bruijn <willemb@google.com>
----
Changes (rfc -> v1)
- add documentation
- remove unnecessary skb->len test (thanks to Richard Cochran)
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core')
| -rw-r--r-- | net/core/skbuff.c | 19 |
1 files changed, 14 insertions, 5 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 56db472e9b86..65a3798f43e6 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -3710,19 +3710,28 @@ void __skb_tstamp_tx(struct sk_buff *orig_skb, struct sock *sk, int tstype) { struct sk_buff *skb; + bool tsonly = sk->sk_tsflags & SOF_TIMESTAMPING_OPT_TSONLY; if (!sk) return; - if (hwtstamps) - *skb_hwtstamps(orig_skb) = *hwtstamps; + if (tsonly) + skb = alloc_skb(0, GFP_ATOMIC); else - orig_skb->tstamp = ktime_get_real(); - - skb = skb_clone(orig_skb, GFP_ATOMIC); + skb = skb_clone(orig_skb, GFP_ATOMIC); if (!skb) return; + if (tsonly) { + skb_shinfo(skb)->tx_flags = skb_shinfo(orig_skb)->tx_flags; + skb_shinfo(skb)->tskey = skb_shinfo(orig_skb)->tskey; + } + + if (hwtstamps) + *skb_hwtstamps(skb) = *hwtstamps; + else + skb->tstamp = ktime_get_real(); + __skb_complete_tx_timestamp(skb, sk, tstype); } EXPORT_SYMBOL_GPL(__skb_tstamp_tx); |