From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: [PATCH net-next 2/9] tcp: introduce tcp_skb_timestamp_us() helper Date: Fri, 21 Sep 2018 08:51:47 -0700 Message-ID: <20180921155154.49489-3-edumazet@google.com> References: <20180921155154.49489-1-edumazet@google.com> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Cc: netdev , Van Jacobson , Neal Cardwell , Yuchung Cheng , Soheil Hassas Yeganeh , Willem de Bruijn , Eric Dumazet , Eric Dumazet To: "David S . Miller" Return-path: Received: from mail-pf1-f193.google.com ([209.85.210.193]:37046 "EHLO mail-pf1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390320AbeIUVl3 (ORCPT ); Fri, 21 Sep 2018 17:41:29 -0400 Received: by mail-pf1-f193.google.com with SMTP id h69-v6so6164715pfd.4 for ; Fri, 21 Sep 2018 08:52:00 -0700 (PDT) In-Reply-To: <20180921155154.49489-1-edumazet@google.com> Sender: netdev-owner@vger.kernel.org List-ID: There are few places where TCP reads skb->skb_mstamp expecting a value in usec unit. skb->tstamp (aka skb->skb_mstamp) will soon store CLOCK_TAI nsec value. Add tcp_skb_timestamp_us() to provide proper conversion when needed. Signed-off-by: Eric Dumazet --- include/net/tcp.h | 8 +++++++- net/ipv4/tcp_input.c | 11 ++++++----- net/ipv4/tcp_ipv4.c | 2 +- net/ipv4/tcp_output.c | 2 +- net/ipv4/tcp_rate.c | 17 +++++++++-------- net/ipv4/tcp_recovery.c | 5 +++-- 6 files changed, 27 insertions(+), 18 deletions(-) diff --git a/include/net/tcp.h b/include/net/tcp.h index c6f0bc1dc6782a1976c06932e846b3f6d708ba9f..0ca5ea10dc06f3552597c94de31dcd0c8e0ecc32 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -774,6 +774,12 @@ static inline u32 tcp_skb_timestamp(const struct sk_buff *skb) return div_u64(skb->skb_mstamp, USEC_PER_SEC / TCP_TS_HZ); } +/* provide the departure time in us unit */ +static inline u64 tcp_skb_timestamp_us(const struct sk_buff *skb) +{ + return skb->skb_mstamp; +} + #define tcp_flag_byte(th) (((u_int8_t *)th)[13]) @@ -1940,7 +1946,7 @@ static inline s64 tcp_rto_delta_us(const struct sock *sk) { const struct sk_buff *skb = tcp_rtx_queue_head(sk); u32 rto = inet_csk(sk)->icsk_rto; - u64 rto_time_stamp_us = skb->skb_mstamp + jiffies_to_usecs(rto); + u64 rto_time_stamp_us = tcp_skb_timestamp_us(skb) + jiffies_to_usecs(rto); return rto_time_stamp_us - tcp_sk(sk)->tcp_mstamp; } diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index d9034073138ce49c423f7a22143bac415415bc09..d703a0b3b6a2f0efd8607354c1c74ac1a8e78d4f 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -1305,7 +1305,7 @@ static bool tcp_shifted_skb(struct sock *sk, struct sk_buff *prev, */ tcp_sacktag_one(sk, state, TCP_SKB_CB(skb)->sacked, start_seq, end_seq, dup_sack, pcount, - skb->skb_mstamp); + tcp_skb_timestamp_us(skb)); tcp_rate_skb_delivered(sk, skb, state->rate); if (skb == tp->lost_skb_hint) @@ -1580,7 +1580,7 @@ static struct sk_buff *tcp_sacktag_walk(struct sk_buff *skb, struct sock *sk, TCP_SKB_CB(skb)->end_seq, dup_sack, tcp_skb_pcount(skb), - skb->skb_mstamp); + tcp_skb_timestamp_us(skb)); tcp_rate_skb_delivered(sk, skb, state->rate); if (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED) list_del_init(&skb->tcp_tsorted_anchor); @@ -3103,7 +3103,7 @@ static int tcp_clean_rtx_queue(struct sock *sk, u32 prior_fack, tp->retrans_out -= acked_pcount; flag |= FLAG_RETRANS_DATA_ACKED; } else if (!(sacked & TCPCB_SACKED_ACKED)) { - last_ackt = skb->skb_mstamp; + last_ackt = tcp_skb_timestamp_us(skb); WARN_ON_ONCE(last_ackt == 0); if (!first_ackt) first_ackt = last_ackt; @@ -3121,7 +3121,7 @@ static int tcp_clean_rtx_queue(struct sock *sk, u32 prior_fack, tp->delivered += acked_pcount; if (!tcp_skb_spurious_retrans(tp, skb)) tcp_rack_advance(tp, sacked, scb->end_seq, - skb->skb_mstamp); + tcp_skb_timestamp_us(skb)); } if (sacked & TCPCB_LOST) tp->lost_out -= acked_pcount; @@ -3215,7 +3215,8 @@ static int tcp_clean_rtx_queue(struct sock *sk, u32 prior_fack, 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, skb->skb_mstamp)) { + sack_rtt_us > tcp_stamp_us_delta(tp->tcp_mstamp, + tcp_skb_timestamp_us(skb))) { /* Do not re-arm RTO if the sack RTT is measured from data sent * after when the head was last (re)transmitted. Otherwise the * timeout may continue to extend in loss recovery. diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index 09547ef9c4c644fba0f7887afad0a6393e3dd03a..1f2496e8620dd78cecefbb0dceb8570fc92661e5 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -544,7 +544,7 @@ void tcp_v4_err(struct sk_buff *icmp_skb, u32 info) BUG_ON(!skb); tcp_mstamp_refresh(tp); - delta_us = (u32)(tp->tcp_mstamp - skb->skb_mstamp); + delta_us = (u32)(tp->tcp_mstamp - tcp_skb_timestamp_us(skb)); remaining = icsk->icsk_rto - usecs_to_jiffies(delta_us); diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 597dbd749f05dc72e53962a5821861fc218774d6..b95aa72d88233dd6376a70ccd7cbb13744444889 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -1966,7 +1966,7 @@ static bool tcp_tso_should_defer(struct sock *sk, struct sk_buff *skb, head = tcp_rtx_queue_head(sk); if (!head) goto send_now; - age = tcp_stamp_us_delta(tp->tcp_mstamp, head->skb_mstamp); + age = tcp_stamp_us_delta(tp->tcp_mstamp, tcp_skb_timestamp_us(head)); /* If next ACK is likely to come too late (half srtt), do not defer */ if (age < (tp->srtt_us >> 4)) goto send_now; diff --git a/net/ipv4/tcp_rate.c b/net/ipv4/tcp_rate.c index 4dff40dad4dc5ccc372f5108b0d6ba38497ab81f..baed2186c7c623737c739cbc1e35a3c772a8b15a 100644 --- a/net/ipv4/tcp_rate.c +++ b/net/ipv4/tcp_rate.c @@ -55,8 +55,10 @@ void tcp_rate_skb_sent(struct sock *sk, struct sk_buff *skb) * bandwidth estimate. */ if (!tp->packets_out) { - tp->first_tx_mstamp = skb->skb_mstamp; - tp->delivered_mstamp = skb->skb_mstamp; + u64 tstamp_us = tcp_skb_timestamp_us(skb); + + tp->first_tx_mstamp = tstamp_us; + tp->delivered_mstamp = tstamp_us; } TCP_SKB_CB(skb)->tx.first_tx_mstamp = tp->first_tx_mstamp; @@ -88,13 +90,12 @@ void tcp_rate_skb_delivered(struct sock *sk, struct sk_buff *skb, rs->is_app_limited = scb->tx.is_app_limited; rs->is_retrans = scb->sacked & TCPCB_RETRANS; - /* Find the duration of the "send phase" of this window: */ - rs->interval_us = tcp_stamp_us_delta( - skb->skb_mstamp, - scb->tx.first_tx_mstamp); - /* Record send time of most recently ACKed packet: */ - tp->first_tx_mstamp = skb->skb_mstamp; + tp->first_tx_mstamp = tcp_skb_timestamp_us(skb); + /* Find the duration of the "send phase" of this window: */ + rs->interval_us = tcp_stamp_us_delta(tp->first_tx_mstamp, + scb->tx.first_tx_mstamp); + } /* Mark off the skb delivered once it's sacked to avoid being * used again when it's cumulatively acked. For acked packets diff --git a/net/ipv4/tcp_recovery.c b/net/ipv4/tcp_recovery.c index c81aadff769b2c3eee02e6de3a5545c27e8cbc38..fdb715bdd2d11dd33a1474d02892546bbac66f41 100644 --- a/net/ipv4/tcp_recovery.c +++ b/net/ipv4/tcp_recovery.c @@ -50,7 +50,7 @@ static u32 tcp_rack_reo_wnd(const struct sock *sk) s32 tcp_rack_skb_timeout(struct tcp_sock *tp, struct sk_buff *skb, u32 reo_wnd) { return tp->rack.rtt_us + reo_wnd - - tcp_stamp_us_delta(tp->tcp_mstamp, skb->skb_mstamp); + tcp_stamp_us_delta(tp->tcp_mstamp, tcp_skb_timestamp_us(skb)); } /* RACK loss detection (IETF draft draft-ietf-tcpm-rack-01): @@ -91,7 +91,8 @@ static void tcp_rack_detect_loss(struct sock *sk, u32 *reo_timeout) !(scb->sacked & TCPCB_SACKED_RETRANS)) continue; - if (!tcp_rack_sent_after(tp->rack.mstamp, skb->skb_mstamp, + if (!tcp_rack_sent_after(tp->rack.mstamp, + tcp_skb_timestamp_us(skb), tp->rack.end_seq, scb->end_seq)) break; -- 2.19.0.444.g18242da7ef-goog