- Introduce BRIDGE_MPSAFE
- It's enabled only when NET_MPSAFE is defined
in if.h or the kernel config
- Add iflist and rtlist mutex locks
- Locking iflist is performance sensitive,
so it's not used when !BRIDGE_MPSAFE
- Add bif object reference counting
- It enables fine-grain locking for bridge member lists
by allowing to not hold a lock during touching a bif
- bridge_release_member is added to decrement the
reference count
- A condition variable is added to do bridge_delete_member
gracefully
- Add if_bridgeif to ifnet
- It's a shortcut to a bif object of a bridge member
- It reduces a bif lookup cost and so lock contention on iflist
- Make bridgestp MPSAFE too
The network stack of NetBSD is well organized and
layered. A packet reception is processed from a
lower layer to an upper layer one by one. However,
ether_input and bridge_input are not structured so.
bridge_input is called inside ether_input.
The new structure replaces ifnet#if_input of a bridge
member with bridge_input when the member is attached.
So a packet goes straight on a packet reception via
a bridge, bridge_input => ether_input => ip_input.
The change is part of a patch of Lloyd Parkes submitted
in PR 48104. Unlike the patch, the change doesn't
intend to change the behavior of the packet processing.
Another patch will fix PR 48104.
* A sign extension error creating the bridge ID corrupted the
priority (always making it the maximum).
* Do not catch STP packets on an interface for which STP is not
enabled -- it's a violation of the spec, and causes STP to fail on
neighboring bridges.
* An optimization to bstp_input() -- some information is already
known when we call it.
contributed anonymously.
identify sockaddr_dl abuse that remains in the kernel, especially
the potential for overwriting memory past the end of a sockaddr_dl
with, e.g., memcpy(LLADDR(), ...).
Use sockaddr_dl_setaddr() in a few places.
