diff options
| author | David S. Miller <davem@davemloft.net> | 2023-10-23 09:35:02 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2023-10-23 09:35:02 +0100 |
| commit | bdf24b4bdfa59b124f9d0ff837f8d35a908da3b8 (patch) | |
| tree | be82eb8c966ea4a7efa7cd6ed0df9d8968ed9f5d /net/ipv4/tcp_ipv4.c | |
| parent | 35c1b273206346c4178928b1121675dc143e61d2 (diff) | |
| parent | a77a0f5c7f23a8a4981a2a3ff47baa91ceaf1f53 (diff) | |
Merge branch 'tcp-ts-usec-resolution'
Eric Dumazet says:
====================
tcp: add optional usec resolution to TCP TS
As discussed in various public places in 2016, Google adopted
usec resolution in RFC 7323 TS values, at Van Jacobson suggestion.
Goals were :
1) better observability of delays in networking stacks/fabrics.
2) better disambiguation of events based on TSval/ecr values.
3) building block for congestion control modules needing usec resolution.
Back then we implemented a schem based on private SYN options
to safely negotiate the feature.
For upstream submission, we chose to use a much simpler route
attribute because this feature is probably going to be used
in private networks.
ip route add 10/8 ... features tcp_usec_ts
References:
https://www.ietf.org/proceedings/97/slides/slides-97-tcpm-tcp-options-for-low-latency-00.pdf
https://datatracker.ietf.org/doc/draft-wang-tcpm-low-latency-opt/
First two patches are fixing old minor bugs and might be taken
by stable teams (thanks to appropriate Fixes: tags)
====================
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/tcp_ipv4.c')
| -rw-r--r-- | net/ipv4/tcp_ipv4.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index a67a5de86253..7583d4e34c8c 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -296,6 +296,7 @@ int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len) rt = NULL; goto failure; } + tp->tcp_usec_ts = dst_tcp_usec_ts(&rt->dst); /* OK, now commit destination to socket. */ sk->sk_gso_type = SKB_GSO_TCPV4; sk_setup_caps(sk, &rt->dst); @@ -954,7 +955,7 @@ static void tcp_v4_timewait_ack(struct sock *sk, struct sk_buff *skb) tcp_v4_send_ack(sk, skb, tcptw->tw_snd_nxt, tcptw->tw_rcv_nxt, tcptw->tw_rcv_wnd >> tw->tw_rcv_wscale, - tcp_time_stamp_raw() + tcptw->tw_ts_offset, + tcp_tw_tsval(tcptw), tcptw->tw_ts_recent, tw->tw_bound_dev_if, tcp_twsk_md5_key(tcptw), @@ -988,7 +989,7 @@ static void tcp_v4_reqsk_send_ack(const struct sock *sk, struct sk_buff *skb, tcp_v4_send_ack(sk, skb, seq, tcp_rsk(req)->rcv_nxt, req->rsk_rcv_wnd >> inet_rsk(req)->rcv_wscale, - tcp_time_stamp_raw() + tcp_rsk(req)->ts_off, + tcp_rsk_tsval(tcp_rsk(req)), READ_ONCE(req->ts_recent), 0, tcp_md5_do_lookup(sk, l3index, addr, AF_INET), |