This is a note to let you know that I've just added the patch titled
tcp: introduce tcp_skb_timestamp_us() helper
to the 4.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
tcp-introduce-tcp_skb_timestamp_us-helper.patch
and it can be found in the queue-4.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 793a33910e4957f7157d63e6facbd442e2ad813b
Author: Eric Dumazet <edumazet@xxxxxxxxxx>
Date: Fri Sep 21 08:51:47 2018 -0700
tcp: introduce tcp_skb_timestamp_us() helper
[ Upstream commit 2fd66ffba50716fc5ab481c48db643af3bda2276 ]
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 <edumazet@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Stable-dep-of: c8770db2d544 ("tcp: check skb is non-NULL in tcp_rto_delta_us()")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/include/net/tcp.h b/include/net/tcp.h
index 49da4d4a3c3d3..3138f01db6699 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -794,6 +794,12 @@ 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])
@@ -2003,7 +2009,7 @@ 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 9254705afa869..2437a196c1392 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -1301,7 +1301,7 @@ 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)
@@ -1590,7 +1590,7 @@ 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);
@@ -3140,7 +3140,7 @@ 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;
@@ -3158,7 +3158,7 @@ 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;
@@ -3253,7 +3253,8 @@ 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 aa9aa38471f95..d08e9d33e4d79 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -556,7 +556,7 @@ void tcp_v4_err(struct sk_buff *icmp_skb, u32 info)
icsk->icsk_rto = inet_csk_rto_backoff(icsk, TCP_RTO_MAX);
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 fbeb40a481fcb..20bce57a19f09 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -1993,7 +1993,7 @@ 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 4dff40dad4dc5..baed2186c7c62 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;
+ /* Record send time of most recently ACKed packet: */
+ 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(
- skb->skb_mstamp,
- scb->tx.first_tx_mstamp);
+ rs->interval_us = tcp_stamp_us_delta(tp->first_tx_mstamp,
+ scb->tx.first_tx_mstamp);
- /* Record send time of most recently ACKed packet: */
- tp->first_tx_mstamp = skb->skb_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 844ff390f7263..db3469c95c49d 100644
--- a/net/ipv4/tcp_recovery.c
+++ b/net/ipv4/tcp_recovery.c
@@ -51,7 +51,7 @@ 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):
@@ -92,7 +92,8 @@ 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;
