From: Lawrence Brakmo Date: Wed, 11 May 2016 17:02:13 +0000 (-0700) Subject: tcp: replace cnt & rtt with struct in pkts_acked() X-Git-Tag: v4.9.8~2112^2~71 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=756ee1729b2feb3a45767da29e338f70f2086ba3;p=platform%2Fkernel%2Flinux-rpi3.git tcp: replace cnt & rtt with struct in pkts_acked() Replace 2 arguments (cnt and rtt) in the congestion control modules' pkts_acked() function with a struct. This will allow adding more information without having to modify existing congestion control modules (tcp_nv in particular needs bytes in flight when packet was sent). As proposed by Neal Cardwell in his comments to the tcp_nv patch. Signed-off-by: Lawrence Brakmo Acked-by: Yuchung Cheng Signed-off-by: David S. Miller --- diff --git a/include/net/tcp.h b/include/net/tcp.h index 4775a1b..c9ab561 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -854,6 +854,11 @@ enum tcp_ca_ack_event_flags { union tcp_cc_info; +struct ack_sample { + u32 pkts_acked; + s32 rtt_us; +}; + struct tcp_congestion_ops { struct list_head list; u32 key; @@ -877,7 +882,7 @@ struct tcp_congestion_ops { /* new value of cwnd after loss (optional) */ u32 (*undo_cwnd)(struct sock *sk); /* hook for packet ack accounting (optional) */ - void (*pkts_acked)(struct sock *sk, u32 num_acked, s32 rtt_us); + void (*pkts_acked)(struct sock *sk, const struct ack_sample *sample); /* get info for inet_diag (optional) */ size_t (*get_info)(struct sock *sk, u32 ext, int *attr, union tcp_cc_info *info); diff --git a/net/ipv4/tcp_bic.c b/net/ipv4/tcp_bic.c index fd1405d..36087bc 100644 --- a/net/ipv4/tcp_bic.c +++ b/net/ipv4/tcp_bic.c @@ -197,15 +197,15 @@ static void bictcp_state(struct sock *sk, u8 new_state) /* Track delayed acknowledgment ratio using sliding window * ratio = (15*ratio + sample) / 16 */ -static void bictcp_acked(struct sock *sk, u32 cnt, s32 rtt) +static void bictcp_acked(struct sock *sk, const struct ack_sample *sample) { const struct inet_connection_sock *icsk = inet_csk(sk); if (icsk->icsk_ca_state == TCP_CA_Open) { struct bictcp *ca = inet_csk_ca(sk); - cnt -= ca->delayed_ack >> ACK_RATIO_SHIFT; - ca->delayed_ack += cnt; + ca->delayed_ack += sample->pkts_acked - + (ca->delayed_ack >> ACK_RATIO_SHIFT); } } diff --git a/net/ipv4/tcp_cdg.c b/net/ipv4/tcp_cdg.c index ccce8a5..03725b2 100644 --- a/net/ipv4/tcp_cdg.c +++ b/net/ipv4/tcp_cdg.c @@ -294,12 +294,12 @@ static void tcp_cdg_cong_avoid(struct sock *sk, u32 ack, u32 acked) ca->shadow_wnd = max(ca->shadow_wnd, ca->shadow_wnd + incr); } -static void tcp_cdg_acked(struct sock *sk, u32 num_acked, s32 rtt_us) +static void tcp_cdg_acked(struct sock *sk, const struct ack_sample *sample) { struct cdg *ca = inet_csk_ca(sk); struct tcp_sock *tp = tcp_sk(sk); - if (rtt_us <= 0) + if (sample->rtt_us <= 0) return; /* A heuristic for filtering delayed ACKs, adapted from: @@ -307,20 +307,20 @@ static void tcp_cdg_acked(struct sock *sk, u32 num_acked, s32 rtt_us) * delay and rate based TCP mechanisms." TR 100219A. CAIA, 2010. */ if (tp->sacked_out == 0) { - if (num_acked == 1 && ca->delack) { + if (sample->pkts_acked == 1 && ca->delack) { /* A delayed ACK is only used for the minimum if it is * provenly lower than an existing non-zero minimum. */ - ca->rtt.min = min(ca->rtt.min, rtt_us); + ca->rtt.min = min(ca->rtt.min, sample->rtt_us); ca->delack--; return; - } else if (num_acked > 1 && ca->delack < 5) { + } else if (sample->pkts_acked > 1 && ca->delack < 5) { ca->delack++; } } - ca->rtt.min = min_not_zero(ca->rtt.min, rtt_us); - ca->rtt.max = max(ca->rtt.max, rtt_us); + ca->rtt.min = min_not_zero(ca->rtt.min, sample->rtt_us); + ca->rtt.max = max(ca->rtt.max, sample->rtt_us); } static u32 tcp_cdg_ssthresh(struct sock *sk) diff --git a/net/ipv4/tcp_cubic.c b/net/ipv4/tcp_cubic.c index 0ce946e..c99230e 100644 --- a/net/ipv4/tcp_cubic.c +++ b/net/ipv4/tcp_cubic.c @@ -437,21 +437,21 @@ static void hystart_update(struct sock *sk, u32 delay) /* Track delayed acknowledgment ratio using sliding window * ratio = (15*ratio + sample) / 16 */ -static void bictcp_acked(struct sock *sk, u32 cnt, s32 rtt_us) +static void bictcp_acked(struct sock *sk, const struct ack_sample *sample) { const struct tcp_sock *tp = tcp_sk(sk); struct bictcp *ca = inet_csk_ca(sk); u32 delay; /* Some calls are for duplicates without timetamps */ - if (rtt_us < 0) + if (sample->rtt_us < 0) return; /* Discard delay samples right after fast recovery */ if (ca->epoch_start && (s32)(tcp_time_stamp - ca->epoch_start) < HZ) return; - delay = (rtt_us << 3) / USEC_PER_MSEC; + delay = (sample->rtt_us << 3) / USEC_PER_MSEC; if (delay == 0) delay = 1; diff --git a/net/ipv4/tcp_htcp.c b/net/ipv4/tcp_htcp.c index 82f0d9e..4a4d8e7 100644 --- a/net/ipv4/tcp_htcp.c +++ b/net/ipv4/tcp_htcp.c @@ -99,7 +99,7 @@ static inline void measure_rtt(struct sock *sk, u32 srtt) } static void measure_achieved_throughput(struct sock *sk, - u32 pkts_acked, s32 rtt) + const struct ack_sample *sample) { const struct inet_connection_sock *icsk = inet_csk(sk); const struct tcp_sock *tp = tcp_sk(sk); @@ -107,10 +107,10 @@ static void measure_achieved_throughput(struct sock *sk, u32 now = tcp_time_stamp; if (icsk->icsk_ca_state == TCP_CA_Open) - ca->pkts_acked = pkts_acked; + ca->pkts_acked = sample->pkts_acked; - if (rtt > 0) - measure_rtt(sk, usecs_to_jiffies(rtt)); + if (sample->rtt_us > 0) + measure_rtt(sk, usecs_to_jiffies(sample->rtt_us)); if (!use_bandwidth_switch) return; @@ -122,7 +122,7 @@ static void measure_achieved_throughput(struct sock *sk, return; } - ca->packetcount += pkts_acked; + ca->packetcount += sample->pkts_acked; if (ca->packetcount >= tp->snd_cwnd - (ca->alpha >> 7 ? : 1) && now - ca->lasttime >= ca->minRTT && diff --git a/net/ipv4/tcp_illinois.c b/net/ipv4/tcp_illinois.c index 2ab9bbb..c8e6d86 100644 --- a/net/ipv4/tcp_illinois.c +++ b/net/ipv4/tcp_illinois.c @@ -82,30 +82,31 @@ static void tcp_illinois_init(struct sock *sk) } /* Measure RTT for each ack. */ -static void tcp_illinois_acked(struct sock *sk, u32 pkts_acked, s32 rtt) +static void tcp_illinois_acked(struct sock *sk, const struct ack_sample *sample) { struct illinois *ca = inet_csk_ca(sk); + s32 rtt_us = sample->rtt_us; - ca->acked = pkts_acked; + ca->acked = sample->pkts_acked; /* dup ack, no rtt sample */ - if (rtt < 0) + if (rtt_us < 0) return; /* ignore bogus values, this prevents wraparound in alpha math */ - if (rtt > RTT_MAX) - rtt = RTT_MAX; + if (rtt_us > RTT_MAX) + rtt_us = RTT_MAX; /* keep track of minimum RTT seen so far */ - if (ca->base_rtt > rtt) - ca->base_rtt = rtt; + if (ca->base_rtt > rtt_us) + ca->base_rtt = rtt_us; /* and max */ - if (ca->max_rtt < rtt) - ca->max_rtt = rtt; + if (ca->max_rtt < rtt_us) + ca->max_rtt = rtt_us; ++ca->cnt_rtt; - ca->sum_rtt += rtt; + ca->sum_rtt += rtt_us; } /* Maximum queuing delay */ diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index a914e06..d6c8f4cd0 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -3248,8 +3248,12 @@ static int tcp_clean_rtx_queue(struct sock *sk, int prior_fackets, tcp_rearm_rto(sk); } - if (icsk->icsk_ca_ops->pkts_acked) - icsk->icsk_ca_ops->pkts_acked(sk, pkts_acked, ca_rtt_us); + if (icsk->icsk_ca_ops->pkts_acked) { + struct ack_sample sample = { .pkts_acked = pkts_acked, + .rtt_us = ca_rtt_us }; + + icsk->icsk_ca_ops->pkts_acked(sk, &sample); + } #if FASTRETRANS_DEBUG > 0 WARN_ON((int)tp->sacked_out < 0); diff --git a/net/ipv4/tcp_lp.c b/net/ipv4/tcp_lp.c index 1e70fa8..c67ece1 100644 --- a/net/ipv4/tcp_lp.c +++ b/net/ipv4/tcp_lp.c @@ -260,13 +260,13 @@ static void tcp_lp_rtt_sample(struct sock *sk, u32 rtt) * newReno in increase case. * We work it out by following the idea from TCP-LP's paper directly */ -static void tcp_lp_pkts_acked(struct sock *sk, u32 num_acked, s32 rtt_us) +static void tcp_lp_pkts_acked(struct sock *sk, const struct ack_sample *sample) { struct tcp_sock *tp = tcp_sk(sk); struct lp *lp = inet_csk_ca(sk); - if (rtt_us > 0) - tcp_lp_rtt_sample(sk, rtt_us); + if (sample->rtt_us > 0) + tcp_lp_rtt_sample(sk, sample->rtt_us); /* calc inference */ if (tcp_time_stamp > tp->rx_opt.rcv_tsecr) diff --git a/net/ipv4/tcp_vegas.c b/net/ipv4/tcp_vegas.c index 13951c4..4c4bac1 100644 --- a/net/ipv4/tcp_vegas.c +++ b/net/ipv4/tcp_vegas.c @@ -107,16 +107,16 @@ EXPORT_SYMBOL_GPL(tcp_vegas_init); * o min-filter RTT samples from a much longer window (forever for now) * to find the propagation delay (baseRTT) */ -void tcp_vegas_pkts_acked(struct sock *sk, u32 cnt, s32 rtt_us) +void tcp_vegas_pkts_acked(struct sock *sk, const struct ack_sample *sample) { struct vegas *vegas = inet_csk_ca(sk); u32 vrtt; - if (rtt_us < 0) + if (sample->rtt_us < 0) return; /* Never allow zero rtt or baseRTT */ - vrtt = rtt_us + 1; + vrtt = sample->rtt_us + 1; /* Filter to find propagation delay: */ if (vrtt < vegas->baseRTT) diff --git a/net/ipv4/tcp_vegas.h b/net/ipv4/tcp_vegas.h index ef9da53..248cfc0 100644 --- a/net/ipv4/tcp_vegas.h +++ b/net/ipv4/tcp_vegas.h @@ -17,7 +17,7 @@ struct vegas { void tcp_vegas_init(struct sock *sk); void tcp_vegas_state(struct sock *sk, u8 ca_state); -void tcp_vegas_pkts_acked(struct sock *sk, u32 cnt, s32 rtt_us); +void tcp_vegas_pkts_acked(struct sock *sk, const struct ack_sample *sample); void tcp_vegas_cwnd_event(struct sock *sk, enum tcp_ca_event event); size_t tcp_vegas_get_info(struct sock *sk, u32 ext, int *attr, union tcp_cc_info *info); diff --git a/net/ipv4/tcp_veno.c b/net/ipv4/tcp_veno.c index 0d094b9..40171e1 100644 --- a/net/ipv4/tcp_veno.c +++ b/net/ipv4/tcp_veno.c @@ -69,16 +69,17 @@ static void tcp_veno_init(struct sock *sk) } /* Do rtt sampling needed for Veno. */ -static void tcp_veno_pkts_acked(struct sock *sk, u32 cnt, s32 rtt_us) +static void tcp_veno_pkts_acked(struct sock *sk, + const struct ack_sample *sample) { struct veno *veno = inet_csk_ca(sk); u32 vrtt; - if (rtt_us < 0) + if (sample->rtt_us < 0) return; /* Never allow zero rtt or baseRTT */ - vrtt = rtt_us + 1; + vrtt = sample->rtt_us + 1; /* Filter to find propagation delay: */ if (vrtt < veno->basertt) diff --git a/net/ipv4/tcp_westwood.c b/net/ipv4/tcp_westwood.c index c10732e..4b03a2e 100644 --- a/net/ipv4/tcp_westwood.c +++ b/net/ipv4/tcp_westwood.c @@ -99,12 +99,13 @@ static void westwood_filter(struct westwood *w, u32 delta) * Called after processing group of packets. * but all westwood needs is the last sample of srtt. */ -static void tcp_westwood_pkts_acked(struct sock *sk, u32 cnt, s32 rtt) +static void tcp_westwood_pkts_acked(struct sock *sk, + const struct ack_sample *sample) { struct westwood *w = inet_csk_ca(sk); - if (rtt > 0) - w->rtt = usecs_to_jiffies(rtt); + if (sample->rtt_us > 0) + w->rtt = usecs_to_jiffies(sample->rtt_us); } /* diff --git a/net/ipv4/tcp_yeah.c b/net/ipv4/tcp_yeah.c index 3e6a472..028eb04 100644 --- a/net/ipv4/tcp_yeah.c +++ b/net/ipv4/tcp_yeah.c @@ -56,15 +56,16 @@ 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, u32 pkts_acked, s32 rtt_us) +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 = pkts_acked; + yeah->pkts_acked = sample->pkts_acked; - tcp_vegas_pkts_acked(sk, pkts_acked, rtt_us); + tcp_vegas_pkts_acked(sk, sample); } static void tcp_yeah_cong_avoid(struct sock *sk, u32 ack, u32 acked)