| Message ID | 1461019569-3037369-4-git-send-email-kafai@fb.com |
|---|---|
| State | RFC, archived |
| Delegated to: | David Miller |
| Headers | show |
On Mon, Apr 18, 2016 at 6:46 PM, Martin KaFai Lau <kafai@fb.com> wrote: > After receiving sacks, tcp_shifted_skb() will collapse > skbs if possible. tx_flags/tskey/txstamp_ack also has > to be merged in this case. > > This patch resues the tcp_skb_collapse_tstamp() to handle > them. > > BPF Output Before: > ~~~~~ > <no-output-due-to-missing-tstamp-event> > > BPF Output After: > ~~~~~ > <...>-2024 [007] d.s. 88.644374: : ee_data:14599 > > Packetdrill Script: > ~~~~~ > +0 `sysctl -q -w net.ipv4.tcp_min_tso_segs=10` > +0 `sysctl -q -w net.ipv4.tcp_no_metrics_save=1` > +0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 > +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 > +0 bind(3, ..., ...) = 0 > +0 listen(3, 1) = 0 > > 0.100 < S 0:0(0) win 32792 <mss 1460,sackOK,nop,nop,nop,wscale 7> > 0.100 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 7> > 0.200 < . 1:1(0) ack 1 win 257 > 0.200 accept(3, ..., ...) = 4 > +0 setsockopt(4, SOL_TCP, TCP_NODELAY, [1], 4) = 0 > > 0.200 write(4, ..., 1460) = 1460 > +0 setsockopt(4, SOL_SOCKET, 37, [2688], 4) = 0 > 0.200 write(4, ..., 13140) = 13140 > +0 setsockopt(4, SOL_SOCKET, 37, [2176], 4) = 0 > > 0.200 > P. 1:1461(1460) ack 1 > 0.200 > . 1461:8761(7300) ack 1 > 0.200 > P. 8761:14601(5840) ack 1 > > 0.300 < . 1:1(0) ack 1 win 257 <sack 1461:14601,nop,nop> > 0.300 > P. 1:1461(1460) ack 1 > 0.400 < . 1:1(0) ack 14601 win 257 > > 0.400 close(4) = 0 > 0.400 > F. 14601:14601(0) ack 1 > 0.500 < F. 1:1(0) ack 14602 win 257 > 0.500 > . 14602:14602(0) ack 2 > > Signed-off-by: Martin KaFai Lau <kafai@fb.com> > Cc: Eric Dumazet <edumazet@google.com> > Cc: Neal Cardwell <ncardwell@google.com> > Cc: Soheil Hassas Yeganeh <soheil.kdev@gmail.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> > Cc: Willem de Bruijn <willemb@google.com> > Cc: Yuchung Cheng <ycheng@google.com> > --- > include/net/tcp.h | 2 ++ > net/ipv4/tcp_input.c | 1 + > net/ipv4/tcp_output.c | 4 ++-- > 3 files changed, 5 insertions(+), 2 deletions(-) > > diff --git a/include/net/tcp.h b/include/net/tcp.h > index fd40f8c..c0ef054 100644 > --- a/include/net/tcp.h > +++ b/include/net/tcp.h > @@ -557,6 +557,8 @@ void tcp_send_ack(struct sock *sk); > void tcp_send_delayed_ack(struct sock *sk); > void tcp_send_loss_probe(struct sock *sk); > bool tcp_schedule_loss_probe(struct sock *sk); > +void tcp_skb_collapse_tstamp(struct sk_buff *skb, > + const struct sk_buff *next_skb); > > /* tcp_input.c */ > void tcp_resume_early_retransmit(struct sock *sk); > diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c > index 5e45a9c..75e8336 100644 > --- a/net/ipv4/tcp_input.c > +++ b/net/ipv4/tcp_input.c > @@ -1309,6 +1309,7 @@ static bool tcp_shifted_skb(struct sock *sk, struct sk_buff *skb, > if (skb == tcp_highest_sack(sk)) > tcp_advance_highest_sack(sk, skb); > > + tcp_skb_collapse_tstamp(prev, skb); > tcp_unlink_write_queue(skb, sk); > sk_wmem_free_skb(sk, skb); > > diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c > index 889ed96..d21a78f 100644 > --- a/net/ipv4/tcp_output.c > +++ b/net/ipv4/tcp_output.c > @@ -2443,8 +2443,8 @@ u32 __tcp_select_window(struct sock *sk) > return window; > } > > -static void tcp_skb_collapse_tstamp(struct sk_buff *skb, > - const struct sk_buff *next_skb) > +void tcp_skb_collapse_tstamp(struct sk_buff *skb, > + const struct sk_buff *next_skb) > { > const struct skb_shared_info *next_shinfo = skb_shinfo(next_skb); > nice, thanks for the fix! > -- > 2.5.1 >
diff --git a/include/net/tcp.h b/include/net/tcp.h index fd40f8c..c0ef054 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -557,6 +557,8 @@ void tcp_send_ack(struct sock *sk); void tcp_send_delayed_ack(struct sock *sk); void tcp_send_loss_probe(struct sock *sk); bool tcp_schedule_loss_probe(struct sock *sk); +void tcp_skb_collapse_tstamp(struct sk_buff *skb, + const struct sk_buff *next_skb); /* tcp_input.c */ void tcp_resume_early_retransmit(struct sock *sk); diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 5e45a9c..75e8336 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -1309,6 +1309,7 @@ static bool tcp_shifted_skb(struct sock *sk, struct sk_buff *skb, if (skb == tcp_highest_sack(sk)) tcp_advance_highest_sack(sk, skb); + tcp_skb_collapse_tstamp(prev, skb); tcp_unlink_write_queue(skb, sk); sk_wmem_free_skb(sk, skb); diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 889ed96..d21a78f 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -2443,8 +2443,8 @@ u32 __tcp_select_window(struct sock *sk) return window; } -static void tcp_skb_collapse_tstamp(struct sk_buff *skb, - const struct sk_buff *next_skb) +void tcp_skb_collapse_tstamp(struct sk_buff *skb, + const struct sk_buff *next_skb) { const struct skb_shared_info *next_shinfo = skb_shinfo(next_skb);
After receiving sacks, tcp_shifted_skb() will collapse skbs if possible. tx_flags/tskey/txstamp_ack also has to be merged in this case. This patch resues the tcp_skb_collapse_tstamp() to handle them. BPF Output Before: ~~~~~ <no-output-due-to-missing-tstamp-event> BPF Output After: ~~~~~ <...>-2024 [007] d.s. 88.644374: : ee_data:14599 Packetdrill Script: ~~~~~ +0 `sysctl -q -w net.ipv4.tcp_min_tso_segs=10` +0 `sysctl -q -w net.ipv4.tcp_no_metrics_save=1` +0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0 +0 bind(3, ..., ...) = 0 +0 listen(3, 1) = 0 0.100 < S 0:0(0) win 32792 <mss 1460,sackOK,nop,nop,nop,wscale 7> 0.100 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 7> 0.200 < . 1:1(0) ack 1 win 257 0.200 accept(3, ..., ...) = 4 +0 setsockopt(4, SOL_TCP, TCP_NODELAY, [1], 4) = 0 0.200 write(4, ..., 1460) = 1460 +0 setsockopt(4, SOL_SOCKET, 37, [2688], 4) = 0 0.200 write(4, ..., 13140) = 13140 +0 setsockopt(4, SOL_SOCKET, 37, [2176], 4) = 0 0.200 > P. 1:1461(1460) ack 1 0.200 > . 1461:8761(7300) ack 1 0.200 > P. 8761:14601(5840) ack 1 0.300 < . 1:1(0) ack 1 win 257 <sack 1461:14601,nop,nop> 0.300 > P. 1:1461(1460) ack 1 0.400 < . 1:1(0) ack 14601 win 257 0.400 close(4) = 0 0.400 > F. 14601:14601(0) ack 1 0.500 < F. 1:1(0) ack 14602 win 257 0.500 > . 14602:14602(0) ack 2 Signed-off-by: Martin KaFai Lau <kafai@fb.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Soheil Hassas Yeganeh <soheil.kdev@gmail.com> Cc: Willem de Bruijn <willemb@google.com> Cc: Yuchung Cheng <ycheng@google.com> --- include/net/tcp.h | 2 ++ net/ipv4/tcp_input.c | 1 + net/ipv4/tcp_output.c | 4 ++-- 3 files changed, 5 insertions(+), 2 deletions(-)