diff options
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv4/tcp_output.c | 29 |
1 files changed, 17 insertions, 12 deletions
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index a2a796c..8bbd86c 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -1752,20 +1752,23 @@ static int tso_fragment(struct sock *sk, struct sk_buff *skb, unsigned int len, static bool tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb, bool *is_cwnd_limited, u32 max_segs) { - struct tcp_sock *tp = tcp_sk(sk); const struct inet_connection_sock *icsk = inet_csk(sk); - u32 send_win, cong_win, limit, in_flight; + u32 age, send_win, cong_win, limit, in_flight; + struct tcp_sock *tp = tcp_sk(sk); + struct skb_mstamp now; + struct sk_buff *head; int win_divisor; if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) goto send_now; - if (icsk->icsk_ca_state != TCP_CA_Open) + if (!((1 << icsk->icsk_ca_state) & (TCPF_CA_Open | TCPF_CA_CWR))) goto send_now; - /* Defer for less than two clock ticks. */ - if (tp->tso_deferred && - (((u32)jiffies << 1) >> 1) - (tp->tso_deferred >> 1) > 1) + /* Avoid bursty behavior by allowing defer + * only if the last write was recent. + */ + if ((s32)(tcp_time_stamp - tp->lsndtime) > 0) goto send_now; in_flight = tcp_packets_in_flight(tp); @@ -1807,11 +1810,14 @@ static bool tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb, goto send_now; } - /* Ok, it looks like it is advisable to defer. - * Do not rearm the timer if already set to not break TCP ACK clocking. - */ - if (!tp->tso_deferred) - tp->tso_deferred = 1 | (jiffies << 1); + head = tcp_write_queue_head(sk); + skb_mstamp_get(&now); + age = skb_mstamp_us_delta(&now, &head->skb_mstamp); + /* If next ACK is likely to come too late (half srtt), do not defer */ + if (age < (tp->srtt_us >> 4)) + goto send_now; + + /* Ok, it looks like it is advisable to defer. */ if (cong_win < send_win && cong_win < skb->len) *is_cwnd_limited = true; @@ -1819,7 +1825,6 @@ static bool tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb, return true; send_now: - tp->tso_deferred = 0; return false; } |
