sys: Remove $FreeBSD$: two-line .h pattern

Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/

dummynet: use m_rcvif_serialize/restore when queueing packets

This fixed panic with interface being removed while packet
was sitting on a queue. This allows to pass all dummynet
tests including forthcoming dummynet:ipfw_interface_removal
and dummynet:pf_interface_removal and demonstrates use of
m_rcvif_serialize() and m_rcvif_restore().

Reviewed by: kp
Differential revision: https://reviews.freebsd.org/D33267

(cherry picked from commit 165746f4e4bf54c5902a103c2d4a3455e651c58f)

Revert "dummynet: use m_rcvif_serialize/restore when queueing packets"

This reverts commit 165746f4e4bf54c5902a103c2d4a3455e651c58f.

Obtained from: github.com/glebius/FreeBSD/commits/backout-ifindex

dummynet: use m_rcvif_serialize/restore when queueing packets

This fixed panic with interface being removed while packet
was sitting on a queue. This allows to pass all dummynet
tests including forthcoming dummynet:ipfw_interface_removal
and dummynet:pf_interface_removal and demonstrates use of
m_rcvif_serialize() and m_rcvif_restore().

Reviewed by: kp
Differential revision: https://reviews.freebsd.org/D33267

dummynet: drop unused definitions

Reviewed by: kp
Differential Revision: https://reviews.freebsd.org/D33429

VNETify dummynet

This moves dn_cfg and other parameters into per VNET variables.

The taskqueue and control state remains global.

Reviewed by: kp
Differential Revision: https://reviews.freebsd.org/D29274

dummynet: Move packet counters into dn_cfg

Move the packets counters into the dn_cfg struct. This reduces the
global name space use for dummynet and will make future work for things
like vnet support and re-use in pf easier.

Reviewed by: donner
MFC after: 2 weeks
Sponsored by: Rubicon Communications, LLC ("Netgate")
Differential Revision: https://reviews.freebsd.org/D29245

net: clean up empty lines in .c and .h files

Import Dummynet AQM version 0.2.1 (CoDel, FQ-CoDel, PIE and FQ-PIE).

Centre for Advanced Internet Architectures

Implementing AQM in FreeBSD

* Overview <http://caia.swin.edu.au/freebsd/aqm/index.html>

* Articles, Papers and Presentations
<http://caia.swin.edu.au/freebsd/aqm/papers.html>

* Patches and Tools <http://caia.swin.edu.au/freebsd/aqm/downloads.html>

Overview

Recent years have seen a resurgence of interest in better managing
the depth of bottleneck queues in routers, switches and other places
that get congested. Solutions include transport protocol enhancements
at the end-hosts (such as delay-based or hybrid congestion control
schemes) and active queue management (AQM) schemes applied within
bottleneck queues.

The notion of AQM has been around since at least the late 1990s
(e.g. RFC 2309). In recent years the proliferation of oversized
buffers in all sorts of network devices (aka bufferbloat) has
stimulated keen community interest in four new AQM schemes -- CoDel,
FQ-CoDel, PIE and FQ-PIE.

The IETF AQM working group is looking to document these schemes,
and independent implementations are a corner-stone of the IETF's
process for confirming the clarity of publicly available protocol
descriptions. While significant development work on all three schemes
has occured in the Linux kernel, there is very little in FreeBSD.

Project Goals

This project began in late 2015, and aims to design and implement
functionally-correct versions of CoDel, FQ-CoDel, PIE and FQ_PIE
in FreeBSD (with code BSD-licensed as much as practical). We have
chosen to do this as extensions to FreeBSD's ipfw/dummynet firewall
and traffic shaper. Implementation of these AQM schemes in FreeBSD
will:
* Demonstrate whether the publicly available documentation is
sufficient to enable independent, functionally equivalent implementations

* Provide a broader suite of AQM options for sections the networking
community that rely on FreeBSD platforms

Program Members:

* Rasool Al Saadi (developer)

* Grenville Armitage (project lead)

Acknowledgements:

This project has been made possible in part by a gift from the
Comcast Innovation Fund.

Submitted by: Rasool Al-Saadi <ralsaadi@swin.edu.au>
X-No objection: core
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D6388