| Message ID | 1471990953-6793-1-git-send-email-soheil.kdev@gmail.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
On Tue, 2016-08-23 at 18:22 -0400, Soheil Hassas Yeganeh wrote: > From: Soheil Hassas Yeganeh <soheil@google.com> > > Instead of using sock_tx_timestamp, use skb_tx_timestamp to record > software transmit timestamp of a packet. > > sock_tx_timestamp resets and overrides the tx_flags of the skb. > The function is intended to be called from within the protocol > layer when creating the skb, not from a device driver. This is > inconsistent with other drivers and will cause issues for TCP. > Acked-by: Eric Dumazet <edumazet@google.com> Thanks !
From: Soheil Hassas Yeganeh <soheil.kdev@gmail.com> Date: Tue, 23 Aug 2016 18:22:33 -0400 > From: Soheil Hassas Yeganeh <soheil@google.com> > > Instead of using sock_tx_timestamp, use skb_tx_timestamp to record > software transmit timestamp of a packet. > > sock_tx_timestamp resets and overrides the tx_flags of the skb. > The function is intended to be called from within the protocol > layer when creating the skb, not from a device driver. This is > inconsistent with other drivers and will cause issues for TCP. > > In TCP, we intend to sample the timestamps for the last byte > for each sendmsg/sendpage. For that reason, tcp_sendmsg calls > tcp_tx_timestamp only with the last skb that it generates. > For example, if a 128KB message is split into two 64KB packets > we want to sample the SND timestamp of the last packet. The current > code in the tun driver, however, will result in sampling the SND > timestamp for both packets. > > Also, when the last packet is split into smaller packets for > retranmission (see tcp_fragment), the tun driver will record > timestamps for all of the retransmitted packets and not only the > last packet. > > Fixes: eda297729171 (tun: Support software transmit time stamping.) > Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> > Signed-off-by: Francis Yan <francisyyan@google.com> Applied and queued up for -stable, thanks.
diff --git a/drivers/net/tun.c b/drivers/net/tun.c index e249428..8093e39 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -888,11 +888,7 @@ static netdev_tx_t tun_net_xmit(struct sk_buff *skb, struct net_device *dev) if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC))) goto drop; - if (skb->sk && sk_fullsock(skb->sk)) { - sock_tx_timestamp(skb->sk, skb->sk->sk_tsflags, - &skb_shinfo(skb)->tx_flags); - sw_tx_timestamp(skb); - } + skb_tx_timestamp(skb); /* Orphan the skb - required as we might hang on to it * for indefinite time.