Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFC r267336:

PF_BLUETOOTH protocols: skip initialization of non-virtualized globals
for non-default VNET instances.

This fixes panic on a vnet initialization when ng_btsocket is loaded.

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Mechanically substitute flags from historic mbuf allocator with
malloc(9) flags within sys.

Exceptions:

- sys/contrib not touched
- sys/mbuf.h edited manually

Mark all SYSCTL_NODEs static that have no corresponding SYSCTL_DECLs.

The SYSCTL_NODE macro defines a list that stores all child-elements of
that node. If there's no SYSCTL_DECL macro anywhere else, there's no
reason why it shouldn't be static.

Mark MALLOC_DEFINEs static that have no corresponding MALLOC_DECLAREs.

This means that their use is restricted to a single C file.

Mfp4 CH=177274,177280,177284-177285,177297,177324-177325

VNET socket push back:
try to minimize the number of places where we have to switch vnets
and narrow down the time we stay switched. Add assertions to the
socket code to catch possibly unset vnets as seen in r204147.

While this reduces the number of vnet recursion in some places like
NFS, POSIX local sockets and some netgraph, .. recursions are
impossible to fix.

The current expectations are documented at the beginning of
uipc_socket.c along with the other information there.

Sponsored by: The FreeBSD Foundation
Sponsored by: CK Software GmbH
Reviewed by: jhb
Tested by: zec

Tested by: Mikolaj Golub (to.my.trociny gmail.com)
MFC after: 2 weeks

sysctl(9) cleanup checkpoint: amd64 GENERIC builds cleanly.

Commit the netgraph piece.

Retire the MALLOC and FREE macros. They are an abomination unto style(9).

MFC after: 3 months

Implement ratelimiting for debug messages. For now, allow at most
one message per second. In the future might add a sysctl knob for
each socket family to fine tune this.

MFC after: 1 week

Fix locking bug, i.e. lock "wildcard" matched pcb before return.

Introduce support for Bluetooth SCO sockets. This is based on older
code that was revisted.

MFC after: 3 months