rack, bbr: cleanup ack throttling

Use the variable in the TCPCB, not the one in the stack specific
data structure. This simplifies the code and brings the functionality
to BBR without any change.

R

rack, bbr: cleanup ack throttling

Use the variable in the TCPCB, not the one in the stack specific
data structure. This simplifies the code and brings the functionality
to BBR without any change.

Reviewed by: Peter Lei, cc
MFC after: 1 week
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D46068

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

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

tcp: reduce argument list to functions that pass a segment

The socket argument is superfluous, as a tcpcb always has one and
only one socket.

Reviewed by: rrs
Differential Revision: https://review

tcp: reduce argument list to functions that pass a segment

The socket argument is superfluous, as a tcpcb always has one and
only one socket.

Reviewed by: rrs
Differential Revision: https://reviews.freebsd.org/D39434

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Update rack to the latest code used at NF.

There have been many changes to rack over the last couple of years, including:
a) Ability when switching stacks to have one stack query another.

Update rack to the latest code used at NF.

There have been many changes to rack over the last couple of years, including:
a) Ability when switching stacks to have one stack query another.
b) Internal use of micro-second timers instead of ticks.
c) Many changes to pacing in forms of
1) Improvements to Dynamic Goodput Pacing (DGP)
2) Improvements to fixed rate paciing
3) A new feature called hybrid pacing where the requestor can
get a combination of DGP and fixed rate pacing with deadlines
for delivery that can dynamically speed things up.
d) All kinds of bugs found during extensive testing and use of the
rack stack for streaming video and in fact all data transferred
by NF

Reviewed by: glebius, gallatin, tuexen
Sponsored By: Netflix Inc.
Differential Revision: https://reviews.freebsd.org/D39402

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tcp: ECN preparations for ECN++, AccECN (tcp_respond)

tcp_respond is another function to build a tcp control packet
quickly. With ECN++ and AccECN, both the IP ECN header, and
the TCP ECN flags are

tcp: ECN preparations for ECN++, AccECN (tcp_respond)

tcp_respond is another function to build a tcp control packet
quickly. With ECN++ and AccECN, both the IP ECN header, and
the TCP ECN flags are supposed to reflect the correct state.

Also ensure that on receiving multiple ECN SYN-ACKs, the
responses triggered will reflect the latest state.

Reviewed By: tuexen, #transport
Sponsored by: NetApp, Inc.
Differential Revision: https://reviews.freebsd.org/D36973

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tcp: Rack ack war with a mis-behaving firewall or nat with resets.

Previously we added ack-war prevention for misbehaving firewalls. This is
where the f/w or nat messes up its sequence numbers and c

tcp: Rack ack war with a mis-behaving firewall or nat with resets.

Previously we added ack-war prevention for misbehaving firewalls. This is
where the f/w or nat messes up its sequence numbers and causes an ack-war.
There is yet another type of ack war that we have found in the wild that is
like unto this. Basically the f/w or nat gets a ack (keep-alive probe or such)
and instead of turning the ack/seq around and adding a TH_RST it does something
real stupid and sends a new packet with seq=0. This of course triggers the challenge
ack in the reset processing which then sends in a challenge ack (if the seq=0 is within
the range of possible sequence numbers allowed by the challenge) and then we rinse-repeat.

This will add the needed tweaks (similar to the last ack-war prevention using the same sysctls and counters)
to prevent it and allow say 5 per second by default.

Reviewed by: Michael Tuexen
Sponsored by: Netflix Inc.
Differential Revision: https://reviews.freebsd.org/D32938

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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

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This commit brings things into sync with the advancements that
have been made in rack and adds a few fixes in BBR. This also
removes any possibility of incorrectly doing OOB data the stacks
do not su

This commit brings things into sync with the advancements that
have been made in rack and adds a few fixes in BBR. This also
removes any possibility of incorrectly doing OOB data the stacks
do not support it. Should fix the skyzaller crashes seen in the
past. Still to fix is the BBR issue just reported this weekend
with the SYN and on sending a RST. Note that this version of
rack can now do pacing as well.

Sponsored by:Netflix Inc
Differential Revision:https://reviews.freebsd.org/D24576

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Merge ^/head r357662 through r357854.

Remove all trailing white space from the BBR/Rack fold. Bits
left around by emacs (thanks emacs).

Now that all of the stats framework is
in FreeBSD the bits that disabled stats
when netflix-stats is not defined is no longer
needed. Lets remove these bits so that we
will properly use stats per its

Now that all of the stats framework is
in FreeBSD the bits that disabled stats
when netflix-stats is not defined is no longer
needed. Lets remove these bits so that we
will properly use stats per its definition
in BBR and Rack.

Sponsored by: Netflix Inc
Differential Revision: https://reviews.freebsd.org/D23088

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This commit is a bit of a re-arrange of deck chairs. It
gets both rack and bbr ready for the completion of the STATs
framework in FreeBSD. For now if you don't have both NF_stats and
stats on it disa

This commit is a bit of a re-arrange of deck chairs. It
gets both rack and bbr ready for the completion of the STATs
framework in FreeBSD. For now if you don't have both NF_stats and
stats on it disables them. As soon as the rest of the stats framework
lands we can remove that restriction and then just uses stats when
defined.

Sponsored by: Netflix Inc.
Differential Revision: https://reviews.freebsd.org/D22479

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Merge ^/head r352587 through r352763.

This commit adds BBR (Bottleneck Bandwidth and RTT) congestion control. This
is a completely separate TCP stack (tcp_bbr.ko) that will be built only if
you add the make options WITH_EXTRA_TCP_STACKS=

This commit adds BBR (Bottleneck Bandwidth and RTT) congestion control. This
is a completely separate TCP stack (tcp_bbr.ko) that will be built only if
you add the make options WITH_EXTRA_TCP_STACKS=1 and also include the option
TCPHPTS. You can also include the RATELIMIT option if you have a NIC interface that
supports hardware pacing, BBR understands how to use such a feature.

Note that this commit also adds in a general purpose time-filter which
allows you to have a min-filter or max-filter. A filter allows you to
have a low (or high) value for some period of time and degrade slowly
to another value has time passes. You can find out the details of
BBR by looking at the original paper at:

https://queue.acm.org/detail.cfm?id=3022184

or consult many other web resources you can find on the web
referenced by "BBR congestion control". It should be noted that
BBRv1 (which this is) does tend to unfairness in cases of small
buffered paths, and it will usually get less bandwidth in the case
of large BDP paths(when competing with new-reno or cubic flows). BBR
is still an active research area and we do plan on implementing V2
of BBR to see if it is an improvement over V1.

Sponsored by: Netflix Inc.
Differential Revision: https://reviews.freebsd.org/D21582

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MFHead @r350386

Sponsored by: The FreeBSD Foundation

This commit updates rack to what is basically being used at NF as
well as sets in some of the groundwork for committing BBR. The
hpts system is updated as well as some other needed utilities
for the

This commit updates rack to what is basically being used at NF as
well as sets in some of the groundwork for committing BBR. The
hpts system is updated as well as some other needed utilities
for the entrance of BBR. This is actually part 1 of 3 more
needed commits which will finally complete with BBRv1 being
added as a new tcp stack.

Sponsored by: Netflix Inc.
Differential Revision: https://reviews.freebsd.org/D20834

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Merge ^/head r343712 through r343806.

Regularize the Netflix copyright

Use recent best practices for Copyright form at the top of
the license:
1. Remove all the All Rights Reserved clauses on our stuff. Where we
piggybacked others, u

Regularize the Netflix copyright

Use recent best practices for Copyright form at the top of
the license:
1. Remove all the All Rights Reserved clauses on our stuff. Where we
piggybacked others, use a separate line to make things clear.
2. Use "Netflix, Inc." everywhere.
3. Use a single line for the copyright for grep friendliness.
4. Use date ranges in all places for our stuff.

Approved by: Netflix Legal (who gave me the form), adrian@ (pmc files)

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This commit brings in a new refactored TCP stack called Rack.
Rack includes the following features:
- A different SACK processing scheme (the old sack structures are not used).
- RACK (Recent ackno

This commit brings in a new refactored TCP stack called Rack.
Rack includes the following features:
- A different SACK processing scheme (the old sack structures are not used).
- RACK (Recent acknowledgment) where counting dup-acks is no longer done
instead time is used to knwo when to retransmit. (see the I-D)
- TLP (Tail Loss Probe) where we will probe for tail-losses to attempt
to try not to take a retransmit time-out. (see the I-D)
- Burst mitigation using TCPHTPS
- PRR (partial rate reduction) see the RFC.

Once built into your kernel, you can select this stack by either
socket option with the name of the stack is "rack" or by setting
the global sysctl so the default is rack.

Note that any connection that does not support SACK will be kicked
back to the "default" base FreeBSD stack (currently known as "default").

To build this into your kernel you will need to enable in your
kernel:
makeoptions WITH_EXTRA_TCP_STACKS=1
options TCPHPTS

Sponsored by: Netflix Inc.
Differential Revision: https://reviews.freebsd.org/D15525

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