diff options
| author | Pengcheng Yang <yangpc@wangsu.com> | 2020-03-16 09:35:11 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2020-03-17 04:26:55 +0300 |
| commit | fa4cb9eba3c705bf2216fe238f25dfd0a9619d2e (patch) | |
| tree | 249c0f7574af26c2b742b0aafd6123231cc8a9bf /net/ipv4 | |
| parent | ca04f5d4bb79ef22b708ebb8ab147fc5abb25300 (diff) | |
| download | linux-fa4cb9eba3c705bf2216fe238f25dfd0a9619d2e.tar.xz | |
tcp: fix stretch ACK bugs in Yeah
Change Yeah to properly handle stretch ACKs in additive
increase mode by passing in the count of ACKed packets
to tcp_cong_avoid_ai().
In addition, we re-implemented the scalable path using
tcp_cong_avoid_ai() and removed the pkts_acked variable.
Signed-off-by: Pengcheng Yang <yangpc@wangsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4')
| -rw-r--r-- | net/ipv4/tcp_yeah.c | 41 |
1 files changed, 11 insertions, 30 deletions
diff --git a/net/ipv4/tcp_yeah.c b/net/ipv4/tcp_yeah.c index e00570dd0a69..3bb448761ca3 100644 --- a/net/ipv4/tcp_yeah.c +++ b/net/ipv4/tcp_yeah.c @@ -36,8 +36,6 @@ struct yeah { u32 reno_count; u32 fast_count; - - u32 pkts_acked; }; static void tcp_yeah_init(struct sock *sk) @@ -57,18 +55,6 @@ static void tcp_yeah_init(struct sock *sk) tp->snd_cwnd_clamp = min_t(u32, tp->snd_cwnd_clamp, 0xffffffff/128); } -static void tcp_yeah_pkts_acked(struct sock *sk, - const struct ack_sample *sample) -{ - const struct inet_connection_sock *icsk = inet_csk(sk); - struct yeah *yeah = inet_csk_ca(sk); - - if (icsk->icsk_ca_state == TCP_CA_Open) - yeah->pkts_acked = sample->pkts_acked; - - tcp_vegas_pkts_acked(sk, sample); -} - static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack, u32 acked) { struct tcp_sock *tp = tcp_sk(sk); @@ -77,24 +63,19 @@ static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack, u32 acked) if (!tcp_is_cwnd_limited(sk)) return; - if (tcp_in_slow_start(tp)) - tcp_slow_start(tp, acked); + if (tcp_in_slow_start(tp)) { + acked = tcp_slow_start(tp, acked); + if (!acked) + goto do_vegas; + } - else if (!yeah->doing_reno_now) { + if (!yeah->doing_reno_now) { /* Scalable */ - - tp->snd_cwnd_cnt += yeah->pkts_acked; - if (tp->snd_cwnd_cnt > min(tp->snd_cwnd, TCP_SCALABLE_AI_CNT)) { - if (tp->snd_cwnd < tp->snd_cwnd_clamp) - tp->snd_cwnd++; - tp->snd_cwnd_cnt = 0; - } - - yeah->pkts_acked = 1; - + tcp_cong_avoid_ai(tp, min(tp->snd_cwnd, TCP_SCALABLE_AI_CNT), + acked); } else { /* Reno */ - tcp_cong_avoid_ai(tp, tp->snd_cwnd, 1); + tcp_cong_avoid_ai(tp, tp->snd_cwnd, acked); } /* The key players are v_vegas.beg_snd_una and v_beg_snd_nxt. @@ -118,7 +99,7 @@ static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack, u32 acked) * of bytes we send in an RTT is often less than our cwnd will allow. * So we keep track of our cwnd separately, in v_beg_snd_cwnd. */ - +do_vegas: if (after(ack, yeah->vegas.beg_snd_nxt)) { /* We do the Vegas calculations only if we got enough RTT * samples that we can be reasonably sure that we got @@ -232,7 +213,7 @@ static struct tcp_congestion_ops tcp_yeah __read_mostly = { .set_state = tcp_vegas_state, .cwnd_event = tcp_vegas_cwnd_event, .get_info = tcp_vegas_get_info, - .pkts_acked = tcp_yeah_pkts_acked, + .pkts_acked = tcp_vegas_pkts_acked, .owner = THIS_MODULE, .name = "yeah", |