Multiprocessor Locking Macros

Multiprocessor Locking Macros

Under BSD networking, drivers interface with the protocol stacks by queueing incoming packets on a per-protocol input queue. In a multiprocessor, each protocol input queue must be protected by the locking macros defined in the file net/if.h.

All the locking macros that protect the input queue are assumed to be called at the proper processor interrupt masking level, splimp. All input queue locking macros also take an input parameter ifq, which is a pointer to the protocol input queue that must be defined as a struct ifqueue.