diff options
| author | Yuchung Cheng <ycheng@google.com> | 2021-09-23 21:17:07 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2021-09-24 14:16:40 +0100 |
| commit | 40bc6063796ec77b6073861f9a1993be20d5befd (patch) | |
| tree | cc2672d4809c34d3f8318724bb557a9fb641ddca /net/ipv4/tcp_input.c | |
| parent | ae98f40d32cd0ee6fc222e765734ffa497a0a95e (diff) | |
| download | linux-40bc6063796ec77b6073861f9a1993be20d5befd.tar.bz2 | |
tcp: tracking packets with CE marks in BW rate sample
In order to track CE marks per rate sample (one round trip), TCP needs a
per-skb header field to record the tp->delivered_ce count when the skb
was sent. To make space, we replace the "last_in_flight" field which is
used exclusively for NV congestion control. The stat needed by NV can be
alternatively approximated by existing stats tcp_sock delivered and
mss_cache.
This patch counts the number of packets delivered which have CE marks in
the rate sample, using similar approach of delivery accounting.
Cc: Lawrence Brakmo <brakmo@fb.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Luke Hsiao <lukehsiao@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/tcp_input.c')
| -rw-r--r-- | net/ipv4/tcp_input.c | 11 |
1 files changed, 5 insertions, 6 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 141e85e6422b..53675e284841 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -3221,7 +3221,6 @@ static int tcp_clean_rtx_queue(struct sock *sk, const struct sk_buff *ack_skb, long seq_rtt_us = -1L; long ca_rtt_us = -1L; u32 pkts_acked = 0; - u32 last_in_flight = 0; bool rtt_update; int flag = 0; @@ -3257,7 +3256,6 @@ static int tcp_clean_rtx_queue(struct sock *sk, const struct sk_buff *ack_skb, if (!first_ackt) first_ackt = last_ackt; - last_in_flight = TCP_SKB_CB(skb)->tx.in_flight; if (before(start_seq, reord)) reord = start_seq; if (!after(scb->end_seq, tp->high_seq)) @@ -3323,8 +3321,8 @@ static int tcp_clean_rtx_queue(struct sock *sk, const struct sk_buff *ack_skb, seq_rtt_us = tcp_stamp_us_delta(tp->tcp_mstamp, first_ackt); ca_rtt_us = tcp_stamp_us_delta(tp->tcp_mstamp, last_ackt); - if (pkts_acked == 1 && last_in_flight < tp->mss_cache && - last_in_flight && !prior_sacked && fully_acked && + if (pkts_acked == 1 && fully_acked && !prior_sacked && + (tp->snd_una - prior_snd_una) < tp->mss_cache && sack->rate->prior_delivered + 1 == tp->delivered && !(flag & (FLAG_CA_ALERT | FLAG_SYN_ACKED))) { /* Conservatively mark a delayed ACK. It's typically @@ -3381,9 +3379,10 @@ static int tcp_clean_rtx_queue(struct sock *sk, const struct sk_buff *ack_skb, if (icsk->icsk_ca_ops->pkts_acked) { struct ack_sample sample = { .pkts_acked = pkts_acked, - .rtt_us = sack->rate->rtt_us, - .in_flight = last_in_flight }; + .rtt_us = sack->rate->rtt_us }; + sample.in_flight = tp->mss_cache * + (tp->delivered - sack->rate->prior_delivered); icsk->icsk_ca_ops->pkts_acked(sk, &sample); } |