On Wed, Aug 02, 2023 at 11:33:13AM +0200, Gerd Bayer wrote: > Tuning of the effective buffer size through setsockopts was working for > SMC traffic only but not for TCP fall-back connections even before > commit 0227f058aa29 ("net/smc: Unbind r/w buffer size from clcsock and > make them tunable"). That change made it apparent that TCP fall-back > connections would use net.smc.[rw]mem as buffer size instead of > net.ipv4_tcp_[rw]mem. > > Amend the code that copies attributes between the (TCP) clcsock and the > SMC socket and adjust buffer sizes appropriately: > - Copy over sk_userlocks so that both sockets agree on whether tuning > via setsockopt is active. > - When falling back to TCP use sk_sndbuf or sk_rcvbuf as specified with > setsockopt. Otherwise, use the sysctl value for TCP/IPv4. > - Likewise, use either values from setsockopt or from sysctl for SMC > (duplicated) on successful SMC connect. > > In smc_tcp_listen_work() drop the explicit copy of buffer sizes as that > is taken care of by the attribute copy. > > Fixes: 0227f058aa29 ("net/smc: Unbind r/w buffer size from clcsock and make them tunable") > Signed-off-by: Gerd Bayer <gbayer@xxxxxxxxxxxxx> > Reviewed-by: Wenjia Zhang <wenjia@xxxxxxxxxxxxx> > Reviewed-by: Jan Karcher <jaka@xxxxxxxxxxxxx> Reviewed-by: Tony Lu <tonylu@xxxxxxxxxxxxxxxxx> > ^^^^ nit: a extra new line here. > --- > net/smc/af_smc.c | 76 ++++++++++++++++++++++++++++++++++-------------- > 1 file changed, 54 insertions(+), 22 deletions(-) > > diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c > index 1fcf1e42474a..1c8ed19041d7 100644 > --- a/net/smc/af_smc.c > +++ b/net/smc/af_smc.c > @@ -436,13 +436,63 @@ static int smc_bind(struct socket *sock, struct sockaddr *uaddr, > return rc; > } > > +/* copy only relevant settings and flags of SOL_SOCKET level from smc to > + * clc socket (since smc is not called for these options from net/core) > + */ > + > +#define SK_FLAGS_SMC_TO_CLC ((1UL << SOCK_URGINLINE) | \ > + (1UL << SOCK_KEEPOPEN) | \ > + (1UL << SOCK_LINGER) | \ > + (1UL << SOCK_BROADCAST) | \ > + (1UL << SOCK_TIMESTAMP) | \ > + (1UL << SOCK_DBG) | \ > + (1UL << SOCK_RCVTSTAMP) | \ > + (1UL << SOCK_RCVTSTAMPNS) | \ > + (1UL << SOCK_LOCALROUTE) | \ > + (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \ > + (1UL << SOCK_RXQ_OVFL) | \ > + (1UL << SOCK_WIFI_STATUS) | \ > + (1UL << SOCK_NOFCS) | \ > + (1UL << SOCK_FILTER_LOCKED) | \ > + (1UL << SOCK_TSTAMP_NEW)) > + > +/* if set, use value set by setsockopt() - else use IPv4 or SMC sysctl value */ > +static void smc_adjust_sock_bufsizes(struct sock *nsk, struct sock *osk, > + unsigned long mask) > +{ > + struct net *nnet; > + > + nnet = nsk->sk_net.net; Better to combine these two lines with existed helper. struct net *net = sock_net(nsk); > + > + nsk->sk_userlocks = osk->sk_userlocks; > + > + if (osk->sk_userlocks & SOCK_SNDBUF_LOCK) { > + nsk->sk_sndbuf = osk->sk_sndbuf; > + } else { > + if (mask == SK_FLAGS_SMC_TO_CLC) > + WRITE_ONCE(nsk->sk_sndbuf, > + READ_ONCE(nnet->ipv4.sysctl_tcp_wmem[1])); > + else > + WRITE_ONCE(nsk->sk_sndbuf, > + 2 * READ_ONCE(nnet->smc.sysctl_wmem)); > + } > + if (osk->sk_userlocks & SOCK_RCVBUF_LOCK) { > + nsk->sk_rcvbuf = osk->sk_rcvbuf; > + } else { > + if (mask == SK_FLAGS_SMC_TO_CLC) > + WRITE_ONCE(nsk->sk_rcvbuf, > + READ_ONCE(nnet->ipv4.sysctl_tcp_rmem[1])); > + else > + WRITE_ONCE(nsk->sk_rcvbuf, > + 2 * READ_ONCE(nnet->smc.sysctl_rmem)); > + } > +} > + > static void smc_copy_sock_settings(struct sock *nsk, struct sock *osk, > unsigned long mask) > { > /* options we don't get control via setsockopt for */ > nsk->sk_type = osk->sk_type; > - nsk->sk_sndbuf = osk->sk_sndbuf; > - nsk->sk_rcvbuf = osk->sk_rcvbuf; > nsk->sk_sndtimeo = osk->sk_sndtimeo; > nsk->sk_rcvtimeo = osk->sk_rcvtimeo; > nsk->sk_mark = osk->sk_mark; > @@ -453,26 +503,10 @@ static void smc_copy_sock_settings(struct sock *nsk, struct sock *osk, > > nsk->sk_flags &= ~mask; > nsk->sk_flags |= osk->sk_flags & mask; > + > + smc_adjust_sock_bufsizes(nsk, osk, mask); > } > > -#define SK_FLAGS_SMC_TO_CLC ((1UL << SOCK_URGINLINE) | \ > - (1UL << SOCK_KEEPOPEN) | \ > - (1UL << SOCK_LINGER) | \ > - (1UL << SOCK_BROADCAST) | \ > - (1UL << SOCK_TIMESTAMP) | \ > - (1UL << SOCK_DBG) | \ > - (1UL << SOCK_RCVTSTAMP) | \ > - (1UL << SOCK_RCVTSTAMPNS) | \ > - (1UL << SOCK_LOCALROUTE) | \ > - (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \ > - (1UL << SOCK_RXQ_OVFL) | \ > - (1UL << SOCK_WIFI_STATUS) | \ > - (1UL << SOCK_NOFCS) | \ > - (1UL << SOCK_FILTER_LOCKED) | \ > - (1UL << SOCK_TSTAMP_NEW)) > -/* copy only relevant settings and flags of SOL_SOCKET level from smc to > - * clc socket (since smc is not called for these options from net/core) > - */ > static void smc_copy_sock_settings_to_clc(struct smc_sock *smc) > { > smc_copy_sock_settings(smc->clcsock->sk, &smc->sk, SK_FLAGS_SMC_TO_CLC); > @@ -2479,8 +2513,6 @@ static void smc_tcp_listen_work(struct work_struct *work) > sock_hold(lsk); /* sock_put in smc_listen_work */ > INIT_WORK(&new_smc->smc_listen_work, smc_listen_work); > smc_copy_sock_settings_to_smc(new_smc); > - new_smc->sk.sk_sndbuf = lsmc->sk.sk_sndbuf; > - new_smc->sk.sk_rcvbuf = lsmc->sk.sk_rcvbuf; > sock_hold(&new_smc->sk); /* sock_put in passive closing */ > if (!queue_work(smc_hs_wq, &new_smc->smc_listen_work)) > sock_put(&new_smc->sk); > -- > 2.41.0