On Mon, Aug 15, 2022 at 8:30 PM Jie Meng <jmeng@xxxxxx> wrote: > > Instead of the hardcoded TCP_TIMEOUT_INIT, this diff calls tcp_timeout_init > to initiate req->timeout like the non TFO SYN ACK case. > > Tested using the following packetdrill script, on a host with a BPF > program that sets the initial connect timeout to 10ms. > > `../../common/defaults.sh` > > // Initialize connection > 0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3 > +0 setsockopt(3, SOL_TCP, TCP_FASTOPEN, [1], 4) = 0 > +0 bind(3, ..., ...) = 0 > +0 listen(3, 1) = 0 > > +0 < S 0:0(0) win 32792 <mss 1000,sackOK,FO TFO_COOKIE> > +0 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK> > +.01 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK> > +.02 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK> > +.04 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK> > +.01 < . 1:1(0) ack 1 win 32792 > > +0 accept(3, ..., ...) = 4 > > Signed-off-by: Jie Meng <jmeng@xxxxxx> > --- > net/ipv4/tcp_fastopen.c | 3 ++- > net/ipv4/tcp_timer.c | 2 +- > 2 files changed, 3 insertions(+), 2 deletions(-) > > diff --git a/net/ipv4/tcp_fastopen.c b/net/ipv4/tcp_fastopen.c > index 825b216d11f5..45cc7f1ca296 100644 > --- a/net/ipv4/tcp_fastopen.c > +++ b/net/ipv4/tcp_fastopen.c > @@ -272,8 +272,9 @@ static struct sock *tcp_fastopen_create_child(struct sock *sk, > * The request socket is not added to the ehash > * because it's been added to the accept queue directly. > */ > + req->timeout = tcp_timeout_init(child); > inet_csk_reset_xmit_timer(child, ICSK_TIME_RETRANS, > - TCP_TIMEOUT_INIT, TCP_RTO_MAX); > + req->timeout, TCP_RTO_MAX); > > refcount_set(&req->rsk_refcnt, 2); > > diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c > index b4dfb82d6ecb..cb79127f45c3 100644 > --- a/net/ipv4/tcp_timer.c > +++ b/net/ipv4/tcp_timer.c > @@ -428,7 +428,7 @@ static void tcp_fastopen_synack_timer(struct sock *sk, struct request_sock *req) > if (!tp->retrans_stamp) > tp->retrans_stamp = tcp_time_stamp(tp); > inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS, > - TCP_TIMEOUT_INIT << req->num_timeout, TCP_RTO_MAX); > + req->timeout << req->num_timeout, TCP_RTO_MAX); > } > > > -- Looks good to me. Thanks for the feature! Acked-by: Neal Cardwell <ncardwell@xxxxxxxxxx> neal
