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@linux.ibm.com>
Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com>
Reviewed-by: Jan Karcher <jaka@linux.ibm.com>
---
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;
+
+ 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);
--
2.41.0Hi Gerd,
kernel test robot noticed the following build errors:
[auto build test ERROR on net-next/main]
[also build test ERROR on linus/master v6.5-rc4 next-20230802]
[cannot apply to net/main]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Gerd-Bayer/net-smc-Fix-setsockopt-and-sysctl-to-specify-same-buffer-size-again/20230802-193805
base: net-next/main
patch link: https://lore.kernel.org/r/20230802093313.1501605-3-gbayer%40linux.ibm.com
patch subject: [PATCH net 2/2] net/smc: Use correct buffer sizes when switching between TCP and SMC
config: nios2-randconfig-r006-20230731 (https://download.01.org/0day-ci/archive/20230803/202308030722.dV3X9uUQ-lkp@intel.com/config)
compiler: nios2-linux-gcc (GCC) 12.3.0
reproduce: (https://download.01.org/0day-ci/archive/20230803/202308030722.dV3X9uUQ-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202308030722.dV3X9uUQ-lkp@intel.com/
All errors (new ones prefixed by >>):
net/smc/af_smc.c: In function 'smc_adjust_sock_bufsizes':
>> net/smc/af_smc.c:465:27: error: 'possible_net_t' has no member named 'net'
465 | nnet = nsk->sk_net.net;
| ^
vim +465 net/smc/af_smc.c
438
439 /* copy only relevant settings and flags of SOL_SOCKET level from smc to
440 * clc socket (since smc is not called for these options from net/core)
441 */
442
443 #define SK_FLAGS_SMC_TO_CLC ((1UL << SOCK_URGINLINE) | \
444 (1UL << SOCK_KEEPOPEN) | \
445 (1UL << SOCK_LINGER) | \
446 (1UL << SOCK_BROADCAST) | \
447 (1UL << SOCK_TIMESTAMP) | \
448 (1UL << SOCK_DBG) | \
449 (1UL << SOCK_RCVTSTAMP) | \
450 (1UL << SOCK_RCVTSTAMPNS) | \
451 (1UL << SOCK_LOCALROUTE) | \
452 (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \
453 (1UL << SOCK_RXQ_OVFL) | \
454 (1UL << SOCK_WIFI_STATUS) | \
455 (1UL << SOCK_NOFCS) | \
456 (1UL << SOCK_FILTER_LOCKED) | \
457 (1UL << SOCK_TSTAMP_NEW))
458
459 /* if set, use value set by setsockopt() - else use IPv4 or SMC sysctl value */
460 static void smc_adjust_sock_bufsizes(struct sock *nsk, struct sock *osk,
461 unsigned long mask)
462 {
463 struct net *nnet;
464
> 465 nnet = nsk->sk_net.net;
466
467 nsk->sk_userlocks = osk->sk_userlocks;
468
469 if (osk->sk_userlocks & SOCK_SNDBUF_LOCK) {
470 nsk->sk_sndbuf = osk->sk_sndbuf;
471 } else {
472 if (mask == SK_FLAGS_SMC_TO_CLC)
473 WRITE_ONCE(nsk->sk_sndbuf,
474 READ_ONCE(nnet->ipv4.sysctl_tcp_wmem[1]));
475 else
476 WRITE_ONCE(nsk->sk_sndbuf,
477 2 * READ_ONCE(nnet->smc.sysctl_wmem));
478 }
479 if (osk->sk_userlocks & SOCK_RCVBUF_LOCK) {
480 nsk->sk_rcvbuf = osk->sk_rcvbuf;
481 } else {
482 if (mask == SK_FLAGS_SMC_TO_CLC)
483 WRITE_ONCE(nsk->sk_rcvbuf,
484 READ_ONCE(nnet->ipv4.sysctl_tcp_rmem[1]));
485 else
486 WRITE_ONCE(nsk->sk_rcvbuf,
487 2 * READ_ONCE(nnet->smc.sysctl_rmem));
488 }
489 }
490
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
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@linux.ibm.com>
> Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com>
> Reviewed-by: Jan Karcher <jaka@linux.ibm.com>
Reviewed-by: Tony Lu <tonylu@linux.alibaba.com>
>
^^^^ 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
On Wed, 2023-08-02 at 20:43 +0800, Tony Lu wrote:
> 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@linux.ibm.com>
> > Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com>
> > Reviewed-by: Jan Karcher <jaka@linux.ibm.com>
>
> Reviewed-by: Tony Lu <tonylu@linux.alibaba.com>
>
> >
> ^^^^ nit: a extra new line here.
I'll clean that up.
> > ---
> > net/smc/af_smc.c | 76 ++++++++++++++++++++++++++++++++++----------
> > ----
> > 1 file changed, 54 insertions(+), 22 deletions(-)
> >
> >
[...]
> > +/* 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);
Yes, looks much cleaner.
[...]
>
Thank you Tony for your review and comments.
I'll be sending out a v2 with your recommendations - but give people a
little more time to look at this version.
Thanks,
Gerd
© 2016 - 2026 Red Hat, Inc.