diff options
| author | Neal Cardwell <ncardwell@google.com> | 2025-06-14 20:14:34 -0400 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2025-06-17 16:19:04 -0700 |
| commit | ba4618885b23372c45bb1566ed8e3f1c191ff22d (patch) | |
| tree | d5564a6556f87ff65c4079eade3badc286ea4548 /net/ipv4/tcp_input.c | |
| parent | 1c120191dcec510cc17d587ece48a7ae875a90c5 (diff) | |
tcp: remove RFC3517/RFC6675 hint state: lost_skb_hint, lost_cnt_hint
Now that obsolete RFC3517/RFC6675 TCP loss detection has been removed,
we can remove the somewhat complex and intrusive code to maintain its
hint state: lost_skb_hint and lost_cnt_hint.
This commit makes tcp_clear_retrans_hints_partial() empty. We will
remove tcp_clear_retrans_hints_partial() and its call sites in the
next commit.
Suggested-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Reviewed-by: Yuchung Cheng <ycheng@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250615001435.2390793-3-ncardwell.sw@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/ipv4/tcp_input.c')
| -rw-r--r-- | net/ipv4/tcp_input.c | 19 |
1 files changed, 0 insertions, 19 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index dc234d3854aa..e8e130e946f1 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -1451,11 +1451,6 @@ static u8 tcp_sacktag_one(struct sock *sk, tp->sacked_out += pcount; /* Out-of-order packets delivered */ state->sack_delivered += pcount; - - /* Lost marker hint past SACKed? Tweak RFC3517 cnt */ - if (tp->lost_skb_hint && - before(start_seq, TCP_SKB_CB(tp->lost_skb_hint)->seq)) - tp->lost_cnt_hint += pcount; } /* D-SACK. We can detect redundant retransmission in S|R and plain R @@ -1496,9 +1491,6 @@ static bool tcp_shifted_skb(struct sock *sk, struct sk_buff *prev, tcp_skb_timestamp_us(skb)); tcp_rate_skb_delivered(sk, skb, state->rate); - if (skb == tp->lost_skb_hint) - tp->lost_cnt_hint += pcount; - TCP_SKB_CB(prev)->end_seq += shifted; TCP_SKB_CB(skb)->seq += shifted; @@ -1531,10 +1523,6 @@ static bool tcp_shifted_skb(struct sock *sk, struct sk_buff *prev, if (skb == tp->retransmit_skb_hint) tp->retransmit_skb_hint = prev; - if (skb == tp->lost_skb_hint) { - tp->lost_skb_hint = prev; - tp->lost_cnt_hint -= tcp_skb_pcount(prev); - } TCP_SKB_CB(prev)->tcp_flags |= TCP_SKB_CB(skb)->tcp_flags; TCP_SKB_CB(prev)->eor = TCP_SKB_CB(skb)->eor; @@ -3318,8 +3306,6 @@ static int tcp_clean_rtx_queue(struct sock *sk, const struct sk_buff *ack_skb, next = skb_rb_next(skb); if (unlikely(skb == tp->retransmit_skb_hint)) tp->retransmit_skb_hint = NULL; - if (unlikely(skb == tp->lost_skb_hint)) - tp->lost_skb_hint = NULL; tcp_highest_sack_replace(sk, skb, next); tcp_rtx_queue_unlink_and_free(skb, sk); } @@ -3377,14 +3363,9 @@ static int tcp_clean_rtx_queue(struct sock *sk, const struct sk_buff *ack_skb, if (flag & FLAG_RETRANS_DATA_ACKED) flag &= ~FLAG_ORIG_SACK_ACKED; } else { - int delta; - /* Non-retransmitted hole got filled? That's reordering */ if (before(reord, prior_fack)) tcp_check_sack_reordering(sk, reord, 0); - - delta = prior_sacked - tp->sacked_out; - tp->lost_cnt_hint -= min(tp->lost_cnt_hint, delta); } } else if (skb && rtt_update && sack_rtt_us >= 0 && sack_rtt_us > tcp_stamp_us_delta(tp->tcp_mstamp, |