tcp: Use segment size excluding tcp options for all cwnd calculations

Avoid sending small segments by making sure that cwnd is usually
calculated in full (data) segment sizes. Especially during loss

tcp: Use segment size excluding tcp options for all cwnd calculations

Avoid sending small segments by making sure that cwnd is usually
calculated in full (data) segment sizes. Especially during loss
recovery and retransmission scenarios.

Reviewed By: tuexen, #transport
Sponsored by: NetApp, Inc.
Differential Revision: https://reviews.freebsd.org/D47474

show more ...

tcp cc: Remove a stray semicolon

MFC after: 1 week

tcp cc: remove non-working sctp support

As suggested by lstewart, remove the non-working SCTP support in the
TCP congestion control modules. SCTP has a similar functionality
(although not using kern

tcp cc: remove non-working sctp support

As suggested by lstewart, remove the non-working SCTP support in the
TCP congestion control modules. SCTP has a similar functionality
(although not using kernel loadable modules), on which the TCP stuff
was built on, but the integration was never done.
No functional change intended.

Reviewed by: Peter Lei, cc
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D46142

show more ...

tcp: use enum for all congestion control signals

Facilitate easier troubleshooting by enumerating
all congestion control signals. Typecast the
enum to int, when a congestion control module uses
priv

tcp: use enum for all congestion control signals

Facilitate easier troubleshooting by enumerating
all congestion control signals. Typecast the
enum to int, when a congestion control module uses
private signals.

No external change.

Reviewed By: glebius, tuexen, #transport
Sponsored by: NetApp, Inc.
Differential Revision: https://reviews.freebsd.org/D43838

show more ...

tcp: fix RTO ssthresh for non-6675 pipe calculation

Follow up on D43768 to properly deal with the non-default
pipe calculation. When CC_RTO is processed, the timeout
will have already pulled back sn

tcp: fix RTO ssthresh for non-6675 pipe calculation

Follow up on D43768 to properly deal with the non-default
pipe calculation. When CC_RTO is processed, the timeout
will have already pulled back snd_nxt. Further, snd_fack
is not pulled along with snd_una.

Reviewed By: tuexen, #transport
Sponsored by: NetApp, Inc.
Differential Revision: https://reviews.freebsd.org/D43876

show more ...

tcp: calculate ssthresh on RTO according to RFC5681

per RFC5681, only adjust ssthresh on the initital
retransmission timeout. Since RTO often happens
during loss recovery, while cwnd no longer track

tcp: calculate ssthresh on RTO according to RFC5681

per RFC5681, only adjust ssthresh on the initital
retransmission timeout. Since RTO often happens
during loss recovery, while cwnd no longer tracks
all data in flight, calculcate pipe properly.

Reviewed By: tuexen, #transport
Sponsored by: NetApp, Inc.
Differential Revision: https://reviews.freebsd.org/D43768

show more ...

sys: Automated cleanup of cdefs and other formatting

Apply the following automated changes to try to eliminate
no-longer-needed sys/cdefs.h includes as well as now-empty
blank lines in a row.

Remov

sys: Automated cleanup of cdefs and other formatting

Apply the following automated changes to try to eliminate
no-longer-needed sys/cdefs.h includes as well as now-empty
blank lines in a row.

Remove /^#if.*\n#endif.*\n#include\s+<sys/cdefs.h>.*\n/
Remove /\n+#include\s+<sys/cdefs.h>.*\n+#if.*\n#endif.*\n+/
Remove /\n+#if.*\n#endif.*\n+/
Remove /^#if.*\n#endif.*\n/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/types.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/param.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/capsicum.h>/

Sponsored by: Netflix

show more ...

sys: Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\n/

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

show more ...

Move access to tcp's t_logstate into inline functions and provide new tracepoint and bbpoint capabilities.

The TCP stacks have long accessed t_logstate directly, but in order to do tracepoints and t

Move access to tcp's t_logstate into inline functions and provide new tracepoint and bbpoint capabilities.

The TCP stacks have long accessed t_logstate directly, but in order to do tracepoints and the new bbpoints
we need to move to using the new inline functions. This adds them and moves rack to now use
the tcp_tracepoints.

Reviewed by: tuexen, gallatin
Sponsored by: Netflix Inc
Differential Revision: https://reviews.freebsd.org/D38831

show more ...

Rack cannot be loaded without cc_newreno compiled into the kernel.

Right now rack will fail to load due to its hack in accessing symbol names
in cc_newreno. This was fine when newreno was always com

Rack cannot be loaded without cc_newreno compiled into the kernel.

Right now rack will fail to load due to its hack in accessing symbol names
in cc_newreno. This was fine when newreno was always compiled into the
kernel but now ... not so much. Instead lets fix up rack to use the socket
option queries to get the information it wants and set the parameters. We
also fix the CC parameter so they are always settable.

Reviewed by: tuexen
Sponsored by: Netflix Inc
Differential Revision: https://reviews.freebsd.org/D37622

show more ...

tcp: provide macros to access inpcb and socket from a tcpcb

There should be no functional changes with this commit.

Reviewed by: rscheff
Differential revision: https://reviews.freebsd.org/D37123

tcp: make RACK loadable again using the default configuration

Without this patch, loading the RACK stack required the newreno
CC module to be compiled into the kernel. This is not the case
anymore s

tcp: make RACK loadable again using the default configuration

Without this patch, loading the RACK stack required the newreno
CC module to be compiled into the kernel. This is not the case
anymore since CUBIC is the default now.

Reviewed by: rscheff@
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D36707

show more ...

hystart++ may not properly exit CSS back to slowstart.

In the changes to get hystart++ into cubic an inadvertent line
was removed in the conditional to figure out if you need to exit
hystart++ back

hystart++ may not properly exit CSS back to slowstart.

In the changes to get hystart++ into cubic an inadvertent line
was removed in the conditional to figure out if you need to exit
hystart++ back to slowstart. The line of course is the most crucial
one (the others are valid but not critical) i.e. is the new rtt
less than the point where we entered hystart++. Without the line
we end up bouncing in and out of CSS.

Reported By: Reese Enghardt
Sponsored By: Netflix Inc.

show more ...

tcp: Add hystart++ to our cubic implementation.

As promised to the transport call on 11/4/22 here is an implementation
of hystart++ for cubic. It also cleans up the tcp_congestion function
to have a

tcp: Add hystart++ to our cubic implementation.

As promised to the transport call on 11/4/22 here is an implementation
of hystart++ for cubic. It also cleans up the tcp_congestion function
to have a better name. Common variables are moved into the general
cc.h structure so that both cubic and newreno can use them for
hystart++

Reviewed by: Michael Tuexen, Richard Scheffenegger
Sponsored by: Netflix Inc.
Differential Revision: https://reviews.freebsd.org/D33035

show more ...

tcp: Congestion control cleanup.

NOTE: HEADS UP read the note below if your kernel config is not including GENERIC!!

This patch does a bit of cleanup on TCP congestion control modules. There were s

tcp: Congestion control cleanup.

NOTE: HEADS UP read the note below if your kernel config is not including GENERIC!!

This patch does a bit of cleanup on TCP congestion control modules. There were some rather
interesting surprises that one could get i.e. where you use a socket option to change
from one CC (say cc_cubic) to another CC (say cc_vegas) and you could in theory get
a memory failure and end up on cc_newreno. This is not what one would expect. The
new code fixes this by requiring a cc_data_sz() function so we can malloc with M_WAITOK
and pass in to the init function preallocated memory. The CC init is expected in this
case *not* to fail but if it does and a module does break the
"no fail with memory given" contract we do fall back to the CC that was in place at the time.

This also fixes up a set of common newreno utilities that can be shared amongst other
CC modules instead of the other CC modules reaching into newreno and executing
what they think is a "common and understood" function. Lets put these functions in
cc.c and that way we have a common place that is easily findable by future developers or
bug fixers. This also allows newreno to evolve and grow support for its features i.e. ABE
and HYSTART++ without having to dance through hoops for other CC modules, instead
both newreno and the other modules just call into the common functions if they desire
that behavior or roll there own if that makes more sense.

Note: This commit changes the kernel configuration!! If you are not using GENERIC in
some form you must add a CC module option (one of CC_NEWRENO, CC_VEGAS, CC_CUBIC,
CC_CDG, CC_CHD, CC_DCTCP, CC_HTCP, CC_HD). You can have more than one defined
as well if you desire. Note that if you create a kernel configuration that does not
define a congestion control module and includes INET or INET6 the kernel compile will
break. Also you need to define a default, generic adds 'options CC_DEFAULT=\"newreno\"
but you can specify any string that represents the name of the CC module (same names
that show up in the CC module list under net.inet.tcp.cc). If you fail to add the
options CC_DEFAULT in your kernel configuration the kernel build will also break.

Reviewed by: Michael Tuexen
Sponsored by: Netflix Inc.
RELNOTES:YES
Differential Revision: https://reviews.freebsd.org/D32693

show more ...

tcp: allow new reno functions to be called from other CC modules

Some new reno functions use the internal data, but are also called
from functions of other CC modules. Ensure that in this case, the

tcp: allow new reno functions to be called from other CC modules

Some new reno functions use the internal data, but are also called
from functions of other CC modules. Ensure that in this case, the
internal data is not accessed.

Reported by: syzbot+1d219ea351caa5109d4b@syzkaller.appspotmail.com
Reported by: syzbot+b08144f8cad9c67258c5@syzkaller.appspotmail.com
Reviewed by: rrs
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D32649

show more ...

tcp: Add hystart-plus to cc_newreno and rack.

TCP Hystart draft version -03:
https://datatracker.ietf.org/doc/html/draft-ietf-tcpm-hystartplusplus

Is a new version of hystart that allows one to car

tcp: Add hystart-plus to cc_newreno and rack.

TCP Hystart draft version -03:
https://datatracker.ietf.org/doc/html/draft-ietf-tcpm-hystartplusplus

Is a new version of hystart that allows one to carefully exit slow start if the RTT
spikes too much. The newer version has a slower-slow-start so to speak that then
kicks in for five round trips. To see if you exited too early, if not into congestion avoidance.
This commit will add that feature to our newreno CC and add the needed bits in rack to
be able to enable it.

Reviewed by: tuexen
Sponsored by: Netflix Inc.
Differential Revision: https://reviews.freebsd.org/D32373

show more ...

tcp: fix two bugs in new reno

* Completely initialise the CC module specific data
* Use beta_ecn in case of an ECN event whenever ABE is enabled
or it is requested by the stack.

Reviewed by: rsc

tcp: fix two bugs in new reno

* Completely initialise the CC module specific data
* Use beta_ecn in case of an ECN event whenever ABE is enabled
or it is requested by the stack.

Reviewed by: rscheff, rrs
MFC after: 3 days
Sponsored by: Netflix, Inc.

show more ...

tcp: Use local CC data only in the correct context

Most CC algos do use local data, and when calling
newreno_cong_signal from there, the latter misinterprets
the data as its own struct, leading to i

tcp: Use local CC data only in the correct context

Most CC algos do use local data, and when calling
newreno_cong_signal from there, the latter misinterprets
the data as its own struct, leading to incorrect behavior.

Reported by: chengc_netapp.com
Reviewed By: chengc_netapp.com, tuexen, #transport
MFC after: 3 days
Sponsored By: NetApp, Inc.
Differential Revision: https://reviews.freebsd.org/D30470

show more ...

This brings into sync FreeBSD with the netflix versions of rack and bbr.
This fixes several breakages (panics) since the tcp_lro code was
committed that have been reported. Quite a few new features a

This brings into sync FreeBSD with the netflix versions of rack and bbr.
This fixes several breakages (panics) since the tcp_lro code was
committed that have been reported. Quite a few new features are
now in rack (prefecting of DGP -- Dynamic Goodput Pacing among the
largest). There is also support for ack-war prevention. Documents
comming soon on rack..

Sponsored by: Netflix
Reviewed by: rscheff, mtuexen
Differential Revision: https://reviews.freebsd.org/D30036

show more ...

tcp: Rename rfc6675_pipe to sack.revised, and enable by default

As full support of RFC6675 is in place, deprecating
net.inet.tcp.rfc6675_pipe and enabling by default
net.inet.tcp.sack.revised.

Revi

tcp: Rename rfc6675_pipe to sack.revised, and enable by default

As full support of RFC6675 is in place, deprecating
net.inet.tcp.rfc6675_pipe and enabling by default
net.inet.tcp.sack.revised.

Reviewed By: #transport, kbowling, rrs
Sponsored by: NetApp, Inc.
Differential Revision: https://reviews.freebsd.org/D28702

show more ...

tcp: move cwnd and ssthresh updates into cc modules

This will pave the way of setting ssthresh differently in TCP CUBIC, according
to RFC8312 section 4.7.

No functional change, only code movement.

tcp: move cwnd and ssthresh updates into cc modules

This will pave the way of setting ssthresh differently in TCP CUBIC, according
to RFC8312 section 4.7.

No functional change, only code movement.

Submitted by: chengc_netapp.com
Reviewed by: rrs, tuexen, rscheff
MFC after: 2 weeks
Sponsored by: NetApp, Inc.
Differential Revision: https://reviews.freebsd.org/D26807

show more ...

TCP newreno: improve after_idle ssthresh

Adjust ssthresh in after_idle to the maximum of
the prior ssthresh, or 3/4 of the prior cwnd. See
RFC2861 section 2 for an in depth explanation for
the ratio

TCP newreno: improve after_idle ssthresh

Adjust ssthresh in after_idle to the maximum of
the prior ssthresh, or 3/4 of the prior cwnd. See
RFC2861 section 2 for an in depth explanation for
the rationale around this.

As newreno is the default "fall-through" reaction,
most tcp variants will benefit from this.

Reviewed by: tuexen
MFC after: 2 weeks
Sponsored by: NetApp, Inc.
Differential Revision: https://reviews.freebsd.org/D22438

show more ...

MFH

Sponsored by: Rubicon Communications, LLC (netgate.com)