diff options
Diffstat (limited to 'net/ipv4')
| -rw-r--r-- | net/ipv4/tcp_input.c | 10 | ||||
| -rw-r--r-- | net/ipv4/tcp_output.c | 44 |
2 files changed, 29 insertions, 25 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index f9e4d7ad68b..46aedd6ca02 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -2299,8 +2299,8 @@ tcp_fastretrans_alert(struct sock *sk, int pkts_acked, int flag) * 1. Reno does not count dupacks (sacked_out) automatically. */ if (!tp->packets_out) tp->sacked_out = 0; - /* 2. SACK counts snd_fack in packets inaccurately. */ - if (tp->sacked_out == 0) + + if (WARN_ON(!tp->sacked_out && tp->fackets_out)) tp->fackets_out = 0; /* Now state machine starts. @@ -2568,10 +2568,6 @@ static int tcp_tso_acked(struct sock *sk, struct sk_buff *skb, } else if (*seq_rtt < 0) *seq_rtt = now - scb->when; - if (tp->fackets_out) { - __u32 dval = min(tp->fackets_out, packets_acked); - tp->fackets_out -= dval; - } /* hint's skb might be NULL but we don't need to care */ tp->fastpath_cnt_hint -= min_t(u32, packets_acked, tp->fastpath_cnt_hint); @@ -2657,7 +2653,6 @@ static int tcp_clean_rtx_queue(struct sock *sk, __s32 *seq_rtt_p) seq_rtt = now - scb->when; last_ackt = skb->tstamp; } - tcp_dec_pcount_approx(&tp->fackets_out, skb); tp->packets_out -= tcp_skb_pcount(skb); tcp_unlink_write_queue(skb, sk); sk_stream_free_skb(sk, skb); @@ -2672,6 +2667,7 @@ static int tcp_clean_rtx_queue(struct sock *sk, __s32 *seq_rtt_p) tcp_ack_update_rtt(sk, acked, seq_rtt); tcp_rearm_rto(sk); + tp->fackets_out -= min(pkts_acked, tp->fackets_out); if (tcp_is_reno(tp)) tcp_remove_reno_sacks(sk, pkts_acked); diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 9df5b2a4da6..cbe8bf6dab5 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -652,6 +652,26 @@ static void tcp_set_skb_tso_segs(struct sock *sk, struct sk_buff *skb, unsigned } } +/* When a modification to fackets out becomes necessary, we need to check + * skb is counted to fackets_out or not. Another important thing is to + * tweak SACK fastpath hint too as it would overwrite all changes unless + * hint is also changed. + */ +static void tcp_adjust_fackets_out(struct tcp_sock *tp, struct sk_buff *skb, + int decr) +{ + if (!tp->sacked_out) + return; + + if (!before(tp->highest_sack, TCP_SKB_CB(skb)->seq)) + tp->fackets_out -= decr; + + /* cnt_hint is "off-by-one" compared with fackets_out (see sacktag) */ + if (tp->fastpath_skb_hint != NULL && + after(TCP_SKB_CB(tp->fastpath_skb_hint)->seq, TCP_SKB_CB(skb)->seq)) + tp->fastpath_cnt_hint -= decr; +} + /* Function to create two new TCP segments. Shrinks the given segment * to the specified size and appends a new segment with the rest of the * packet to the list. This won't be called frequently, I hope. @@ -746,21 +766,12 @@ int tcp_fragment(struct sock *sk, struct sk_buff *skb, u32 len, unsigned int mss if (TCP_SKB_CB(skb)->sacked & TCPCB_LOST) tp->lost_out -= diff; - if (diff > 0) { - /* Adjust Reno SACK estimate. */ - if (tcp_is_reno(tp)) { - tcp_dec_pcount_approx_int(&tp->sacked_out, diff); - tcp_verify_left_out(tp); - } - - tcp_dec_pcount_approx_int(&tp->fackets_out, diff); - /* SACK fastpath might overwrite it unless dealt with */ - if (tp->fastpath_skb_hint != NULL && - after(TCP_SKB_CB(tp->fastpath_skb_hint)->seq, - TCP_SKB_CB(skb)->seq)) { - tcp_dec_pcount_approx_int(&tp->fastpath_cnt_hint, diff); - } + /* Adjust Reno SACK estimate. */ + if (tcp_is_reno(tp) && diff > 0) { + tcp_dec_pcount_approx_int(&tp->sacked_out, diff); + tcp_verify_left_out(tp); } + tcp_adjust_fackets_out(tp, skb, diff); } /* Link BUFF into the send queue. */ @@ -1746,10 +1757,7 @@ static void tcp_retrans_try_collapse(struct sock *sk, struct sk_buff *skb, int m if (tcp_is_reno(tp) && tp->sacked_out) tcp_dec_pcount_approx(&tp->sacked_out, next_skb); - /* Not quite right: it can be > snd.fack, but - * it is better to underestimate fackets. - */ - tcp_dec_pcount_approx(&tp->fackets_out, next_skb); + tcp_adjust_fackets_out(tp, skb, tcp_skb_pcount(next_skb)); tp->packets_out -= tcp_skb_pcount(next_skb); sk_stream_free_skb(sk, next_skb); } |