[PATCH] BPF Just-In-Time compiler

Jung-uk Kim jkim at FreeBSD.org
Thu Dec 1 11:17:37 PST 2005

I ported 'jitter' from WinPcap 3.1 to FreeBSD for i386 and wrote amd64 


I didn't do much testing but it seems working pretty well for me so 
far. ;-)

You need the following line in the kernel configuration:

	options	BPF_JITTER

You can turn off filtering through JIT-compiled filter by setting:

	sysctl net.bpf.jitter.enable=0

If you are using very complex filters, it may be useful for you.

Caveats are:

1.  BIOCSETWF is not supported.
2.  bpf_mtap2() is not supported and bpf_mtap() is partially 
3.  amd64 and i386 only.
4.  Intel assembler notation. :-(
5.  ...

Testing, benchmarking, reviews, comments, complaints, patches for 
other architectures, etc, all welcome.


Jung-uk Kim

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