A JIT for packet filters

The Berkeley Packet Filter (BPF) is a mechanism for the fast filtering of network packets on their way to an application. It has its roots in BSD in the very early 1990's, a history that was not enough to prevent the SCO Group from claiming ownership of it. Happily, that claim proved to be as valid as the rest of SCO's assertions, so BPF remains a part of the Linux networking stack. A recent patch from Eric Dumazet may make BPF faster, at least on 64-bit x86 systems.