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Diffstat (limited to 'net/ipv4/tcp_output.c')
-rw-r--r--net/ipv4/tcp_output.c67
1 files changed, 33 insertions, 34 deletions
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 81c640fe0..f5ecbbbc6 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -137,12 +137,12 @@ static __u16 tcp_advertise_mss(struct sock *sk)
}
/* RFC2861. Reset CWND after idle period longer RTO to "restart window".
- * This is the first part of cwnd validation mechanism. */
-static void tcp_cwnd_restart(struct sock *sk, const struct dst_entry *dst)
+ * This is the first part of cwnd validation mechanism.
+ */
+void tcp_cwnd_restart(struct sock *sk, s32 delta)
{
struct tcp_sock *tp = tcp_sk(sk);
- s32 delta = tcp_time_stamp - tp->lsndtime;
- u32 restart_cwnd = tcp_init_cwnd(tp, dst);
+ u32 restart_cwnd = tcp_init_cwnd(tp, __sk_dst_get(sk));
u32 cwnd = tp->snd_cwnd;
tcp_ca_event(sk, CA_EVENT_CWND_RESTART);
@@ -163,20 +163,17 @@ static void tcp_event_data_sent(struct tcp_sock *tp,
{
struct inet_connection_sock *icsk = inet_csk(sk);
const u32 now = tcp_time_stamp;
- const struct dst_entry *dst = __sk_dst_get(sk);
- if (sysctl_tcp_slow_start_after_idle &&
- (!tp->packets_out && (s32)(now - tp->lsndtime) > icsk->icsk_rto))
- tcp_cwnd_restart(sk, __sk_dst_get(sk));
+ if (tcp_packets_in_flight(tp) == 0)
+ tcp_ca_event(sk, CA_EVENT_TX_START);
tp->lsndtime = now;
/* If it is a reply for ato after last received
* packet, enter pingpong mode.
*/
- if ((u32)(now - icsk->icsk_ack.lrcvtime) < icsk->icsk_ack.ato &&
- (!dst || !dst_metric(dst, RTAX_QUICKACK)))
- icsk->icsk_ack.pingpong = 1;
+ if ((u32)(now - icsk->icsk_ack.lrcvtime) < icsk->icsk_ack.ato)
+ icsk->icsk_ack.pingpong = 1;
}
/* Account for an ACK we sent. */
@@ -953,9 +950,6 @@ static int tcp_transmit_skb(struct sock *sk, struct sk_buff *skb, int clone_it,
&md5);
tcp_header_size = tcp_options_size + sizeof(struct tcphdr);
- if (tcp_packets_in_flight(tp) == 0)
- tcp_ca_event(sk, CA_EVENT_TX_START);
-
/* if no packet is in qdisc/device queue, then allow XPS to select
* another queue. We can be called from tcp_tsq_handler()
* which holds one reference to sk_wmem_alloc.
@@ -1783,7 +1777,7 @@ static bool tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb,
if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN)
goto send_now;
- if (!((1 << icsk->icsk_ca_state) & (TCPF_CA_Open | TCPF_CA_CWR)))
+ if (icsk->icsk_ca_state >= TCP_CA_Recovery)
goto send_now;
/* Avoid bursty behavior by allowing defer
@@ -2158,7 +2152,7 @@ repair:
tcp_cwnd_validate(sk, is_cwnd_limited);
return false;
}
- return (push_one == 2) || (!tp->packets_out && tcp_send_head(sk));
+ return !tp->packets_out && tcp_send_head(sk);
}
bool tcp_schedule_loss_probe(struct sock *sk)
@@ -2235,7 +2229,7 @@ static bool skb_still_in_host_queue(const struct sock *sk,
return false;
}
-/* When probe timeout (PTO) fires, send a new segment if one exists, else
+/* When probe timeout (PTO) fires, try send a new segment if possible, else
* retransmit the last segment.
*/
void tcp_send_loss_probe(struct sock *sk)
@@ -2244,11 +2238,19 @@ void tcp_send_loss_probe(struct sock *sk)
struct sk_buff *skb;
int pcount;
int mss = tcp_current_mss(sk);
- int err = -1;
- if (tcp_send_head(sk)) {
- err = tcp_write_xmit(sk, mss, TCP_NAGLE_OFF, 2, GFP_ATOMIC);
- goto rearm_timer;
+ skb = tcp_send_head(sk);
+ if (skb) {
+ if (tcp_snd_wnd_test(tp, skb, mss)) {
+ pcount = tp->packets_out;
+ tcp_write_xmit(sk, mss, TCP_NAGLE_OFF, 2, GFP_ATOMIC);
+ if (tp->packets_out > pcount)
+ goto probe_sent;
+ goto rearm_timer;
+ }
+ skb = tcp_write_queue_prev(sk, skb);
+ } else {
+ skb = tcp_write_queue_tail(sk);
}
/* At most one outstanding TLP retransmission. */
@@ -2256,7 +2258,6 @@ void tcp_send_loss_probe(struct sock *sk)
goto rearm_timer;
/* Retransmit last segment. */
- skb = tcp_write_queue_tail(sk);
if (WARN_ON(!skb))
goto rearm_timer;
@@ -2271,26 +2272,24 @@ void tcp_send_loss_probe(struct sock *sk)
if (unlikely(tcp_fragment(sk, skb, (pcount - 1) * mss, mss,
GFP_ATOMIC)))
goto rearm_timer;
- skb = tcp_write_queue_tail(sk);
+ skb = tcp_write_queue_next(sk, skb);
}
if (WARN_ON(!skb || !tcp_skb_pcount(skb)))
goto rearm_timer;
- err = __tcp_retransmit_skb(sk, skb);
+ if (__tcp_retransmit_skb(sk, skb))
+ goto rearm_timer;
/* Record snd_nxt for loss detection. */
- if (likely(!err))
- tp->tlp_high_seq = tp->snd_nxt;
+ tp->tlp_high_seq = tp->snd_nxt;
+probe_sent:
+ NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_TCPLOSSPROBES);
+ /* Reset s.t. tcp_rearm_rto will restart timer from now */
+ inet_csk(sk)->icsk_pending = 0;
rearm_timer:
- inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
- inet_csk(sk)->icsk_rto,
- TCP_RTO_MAX);
-
- if (likely(!err))
- NET_INC_STATS_BH(sock_net(sk),
- LINUX_MIB_TCPLOSSPROBES);
+ tcp_rearm_rto(sk);
}
/* Push out any pending frames which were held back due to
@@ -3421,7 +3420,7 @@ static int tcp_xmit_probe_skb(struct sock *sk, int urgent, int mib)
*/
tcp_init_nondata_skb(skb, tp->snd_una - !urgent, TCPHDR_ACK);
skb_mstamp_get(&skb->skb_mstamp);
- NET_INC_STATS_BH(sock_net(sk), mib);
+ NET_INC_STATS(sock_net(sk), mib);
return tcp_transmit_skb(sk, skb, 0, GFP_ATOMIC);
}