packet: enable hardware tx timestamping on tpacket ring
authorDaniel Borkmann <dborkman@redhat.com>
Tue, 23 Apr 2013 00:39:29 +0000 (00:39 +0000)
committerDavid S. Miller <davem@davemloft.net>
Thu, 25 Apr 2013 05:22:22 +0000 (01:22 -0400)
Currently, we only have software timestamping for the TX ring buffer
path, but this limitation stems rather from the implementation. By
just reusing tpacket_get_timestamp(), we can also allow hardware
timestamping just as in the RX path.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/packet/af_packet.c

index ec8ea27..9d46a07 100644 (file)
@@ -339,14 +339,33 @@ static int __packet_get_status(struct packet_sock *po, void *frame)
        }
 }
 
+static bool tpacket_get_timestamp(struct sk_buff *skb, struct timespec *ts,
+                                 unsigned int flags)
+{
+       struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
+
+       if (shhwtstamps) {
+               if ((flags & SOF_TIMESTAMPING_SYS_HARDWARE) &&
+                   ktime_to_timespec_cond(shhwtstamps->syststamp, ts))
+                       return true;
+               if ((flags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
+                   ktime_to_timespec_cond(shhwtstamps->hwtstamp, ts))
+                       return true;
+       }
+
+       if (ktime_to_timespec_cond(skb->tstamp, ts))
+               return true;
+
+       return false;
+}
+
 static void __packet_set_timestamp(struct packet_sock *po, void *frame,
-                                  ktime_t tstamp)
+                                  struct sk_buff *skb)
 {
        union tpacket_uhdr h;
        struct timespec ts;
 
-       if (!ktime_to_timespec_cond(tstamp, &ts) ||
-           !sock_flag(&po->sk, SOCK_TIMESTAMPING_SOFTWARE))
+       if (!tpacket_get_timestamp(skb, &ts, po->tp_tstamp))
                return;
 
        h.raw = frame;
@@ -1688,26 +1707,6 @@ drop:
        return 0;
 }
 
-static void tpacket_get_timestamp(struct sk_buff *skb, struct timespec *ts,
-                                 unsigned int flags)
-{
-       struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
-
-       if (shhwtstamps) {
-               if ((flags & SOF_TIMESTAMPING_SYS_HARDWARE) &&
-                   ktime_to_timespec_cond(shhwtstamps->syststamp, ts))
-                       return;
-               if ((flags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
-                   ktime_to_timespec_cond(shhwtstamps->hwtstamp, ts))
-                       return;
-       }
-
-       if (ktime_to_timespec_cond(skb->tstamp, ts))
-               return;
-
-       getnstimeofday(ts);
-}
-
 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
                       struct packet_type *pt, struct net_device *orig_dev)
 {
@@ -1804,7 +1803,8 @@ static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
        spin_unlock(&sk->sk_receive_queue.lock);
 
        skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
-       tpacket_get_timestamp(skb, &ts, po->tp_tstamp);
+       if (!tpacket_get_timestamp(skb, &ts, po->tp_tstamp))
+               getnstimeofday(&ts);
 
        switch (po->tp_version) {
        case TPACKET_V1:
@@ -1908,7 +1908,7 @@ static void tpacket_destruct_skb(struct sk_buff *skb)
                ph = skb_shinfo(skb)->destructor_arg;
                BUG_ON(atomic_read(&po->tx_ring.pending) == 0);
                atomic_dec(&po->tx_ring.pending);
-               __packet_set_timestamp(po, ph, skb->tstamp);
+               __packet_set_timestamp(po, ph, skb);
                __packet_set_status(po, ph, TP_STATUS_AVAILABLE);
        }