diff options
| -rw-r--r-- | net/ipv4/tcp_input.c | 23 |
1 files changed, 17 insertions, 6 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index c7398f05d12b..b85bc7c3736a 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -1048,6 +1048,7 @@ struct tcp_sacktag_state { int reord; int fack_count; int flag; + s32 rtt; /* RTT measured by SACKing never-retransmitted data */ }; /* Check if skb is fully within the SACK block. In presence of GSO skbs, @@ -1108,7 +1109,7 @@ static int tcp_match_skb_to_sack(struct sock *sk, struct sk_buff *skb, static u8 tcp_sacktag_one(struct sock *sk, struct tcp_sacktag_state *state, u8 sacked, u32 start_seq, u32 end_seq, - bool dup_sack, int pcount) + int dup_sack, int pcount, u32 xmit_time) { struct tcp_sock *tp = tcp_sk(sk); int fack_count = state->fack_count; @@ -1148,6 +1149,9 @@ static u8 tcp_sacktag_one(struct sock *sk, state->reord); if (!after(end_seq, tp->high_seq)) state->flag |= FLAG_ORIG_SACK_ACKED; + /* Pick the earliest sequence sacked for RTT */ + if (state->rtt < 0) + state->rtt = tcp_time_stamp - xmit_time; } if (sacked & TCPCB_LOST) { @@ -1205,7 +1209,8 @@ static bool tcp_shifted_skb(struct sock *sk, struct sk_buff *skb, * tcp_highest_sack_seq() when skb is highest_sack. */ tcp_sacktag_one(sk, state, TCP_SKB_CB(skb)->sacked, - start_seq, end_seq, dup_sack, pcount); + start_seq, end_seq, dup_sack, pcount, + TCP_SKB_CB(skb)->when); if (skb == tp->lost_skb_hint) tp->lost_cnt_hint += pcount; @@ -1479,7 +1484,8 @@ static struct sk_buff *tcp_sacktag_walk(struct sk_buff *skb, struct sock *sk, TCP_SKB_CB(skb)->seq, TCP_SKB_CB(skb)->end_seq, dup_sack, - tcp_skb_pcount(skb)); + tcp_skb_pcount(skb), + TCP_SKB_CB(skb)->when); if (!before(TCP_SKB_CB(skb)->seq, tcp_highest_sack_seq(tp))) @@ -1536,7 +1542,7 @@ static int tcp_sack_cache_ok(const struct tcp_sock *tp, const struct tcp_sack_bl static int tcp_sacktag_write_queue(struct sock *sk, const struct sk_buff *ack_skb, - u32 prior_snd_una) + u32 prior_snd_una, s32 *sack_rtt) { struct tcp_sock *tp = tcp_sk(sk); const unsigned char *ptr = (skb_transport_header(ack_skb) + @@ -1554,6 +1560,7 @@ tcp_sacktag_write_queue(struct sock *sk, const struct sk_buff *ack_skb, state.flag = 0; state.reord = tp->packets_out; + state.rtt = -1; if (!tp->sacked_out) { if (WARN_ON(tp->fackets_out)) @@ -1737,6 +1744,7 @@ out: WARN_ON((int)tp->retrans_out < 0); WARN_ON((int)tcp_packets_in_flight(tp) < 0); #endif + *sack_rtt = state.rtt; return state.flag; } @@ -3254,6 +3262,7 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag) int prior_packets = tp->packets_out; const int prior_unsacked = tp->packets_out - tp->sacked_out; int acked = 0; /* Number of packets newly acked */ + s32 sack_rtt = -1; /* If the ack is older than previous acks * then we can probably ignore it. @@ -3310,7 +3319,8 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag) flag |= tcp_ack_update_window(sk, skb, ack, ack_seq); if (TCP_SKB_CB(skb)->sacked) - flag |= tcp_sacktag_write_queue(sk, skb, prior_snd_una); + flag |= tcp_sacktag_write_queue(sk, skb, prior_snd_una, + &sack_rtt); if (TCP_ECN_rcv_ecn_echo(tp, tcp_hdr(skb))) flag |= FLAG_ECE; @@ -3382,7 +3392,8 @@ old_ack: * If data was DSACKed, see if we can undo a cwnd reduction. */ if (TCP_SKB_CB(skb)->sacked) { - flag |= tcp_sacktag_write_queue(sk, skb, prior_snd_una); + flag |= tcp_sacktag_write_queue(sk, skb, prior_snd_una, + &sack_rtt); tcp_fastretrans_alert(sk, acked, prior_unsacked, is_dupack, flag); } |