diff options
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv4/tcp_output.c | 37 |
1 files changed, 23 insertions, 14 deletions
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 3d61c52bdf79..d463c35db33d 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -1402,11 +1402,19 @@ static void tcp_cwnd_application_limited(struct sock *sk) tp->snd_cwnd_stamp = tcp_time_stamp; } -static void tcp_cwnd_validate(struct sock *sk, u32 unsent_segs) +static void tcp_cwnd_validate(struct sock *sk, bool is_cwnd_limited) { struct tcp_sock *tp = tcp_sk(sk); - tp->lsnd_pending = tp->packets_out + unsent_segs; + /* Track the maximum number of outstanding packets in each + * window, and remember whether we were cwnd-limited then. + */ + if (!before(tp->snd_una, tp->max_packets_seq) || + tp->packets_out > tp->max_packets_out) { + tp->max_packets_out = tp->packets_out; + tp->max_packets_seq = tp->snd_nxt; + tp->is_cwnd_limited = is_cwnd_limited; + } if (tcp_is_cwnd_limited(sk)) { /* Network is feed fully. */ @@ -1660,7 +1668,8 @@ static int tso_fragment(struct sock *sk, struct sk_buff *skb, unsigned int len, * * This algorithm is from John Heffner. */ -static bool tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb) +static bool tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb, + bool *is_cwnd_limited) { struct tcp_sock *tp = tcp_sk(sk); const struct inet_connection_sock *icsk = inet_csk(sk); @@ -1724,6 +1733,9 @@ static bool tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb) if (!tp->tso_deferred) tp->tso_deferred = 1 | (jiffies << 1); + if (cong_win < send_win && cong_win < skb->len) + *is_cwnd_limited = true; + return true; send_now: @@ -1881,9 +1893,10 @@ static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle, { struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *skb; - unsigned int tso_segs, sent_pkts, unsent_segs = 0; + unsigned int tso_segs, sent_pkts; int cwnd_quota; int result; + bool is_cwnd_limited = false; sent_pkts = 0; @@ -1908,6 +1921,7 @@ static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle, cwnd_quota = tcp_cwnd_test(tp, skb); if (!cwnd_quota) { + is_cwnd_limited = true; if (push_one == 2) /* Force out a loss probe pkt. */ cwnd_quota = 1; @@ -1924,8 +1938,9 @@ static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle, nonagle : TCP_NAGLE_PUSH)))) break; } else { - if (!push_one && tcp_tso_should_defer(sk, skb)) - goto compute_unsent_segs; + if (!push_one && + tcp_tso_should_defer(sk, skb, &is_cwnd_limited)) + break; } /* TCP Small Queues : @@ -1950,14 +1965,8 @@ static bool tcp_write_xmit(struct sock *sk, unsigned int mss_now, int nonagle, * there is no smp_mb__after_set_bit() yet */ smp_mb__after_clear_bit(); - if (atomic_read(&sk->sk_wmem_alloc) > limit) { - u32 unsent_bytes; - -compute_unsent_segs: - unsent_bytes = tp->write_seq - tp->snd_nxt; - unsent_segs = DIV_ROUND_UP(unsent_bytes, mss_now); + if (atomic_read(&sk->sk_wmem_alloc) > limit) break; - } } limit = mss_now; @@ -1997,7 +2006,7 @@ repair: /* Send one loss probe per tail loss episode. */ if (push_one != 2) tcp_schedule_loss_probe(sk); - tcp_cwnd_validate(sk, unsent_segs); + tcp_cwnd_validate(sk, is_cwnd_limited); return false; } return (push_one == 2) || (!tp->packets_out && tcp_send_head(sk)); |