.\" -*- nroff -*-
.\"
.\"	$NetBSD: bpfjit.4,v 1.2 2014/07/24 21:22:29 wiz Exp $
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.\" Copyright (c) 2014 Alexander Nasonov.
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.Dd July 24, 2014
.Dt BPFJIT 4
.Os
.Sh NAME
.Nm bpfjit
.Nd Just-In-Time compiler for Berkeley Packet Filter
.Sh SYNOPSIS
.Cd "options BPFJIT"
.Cd "options SLJIT"
.Sh DESCRIPTION
The
.Nm
kernel interface adds
.Sy Just-In-Time
compilation of filter programs sent to a
.Xr bpf 4
device.
Instead of being interpreted for every packet,
these filter programs are compiled into native code
and the code is being executed for every packet.
.Pp
The implementation of
.Nm
is based on the
.Sy Stack-Less Just-In-Time
library, or
.Nm sljit
for short.
The library supports multiple platforms including
.Bl -bullet -offset indent -compact
.It
AMD-x86 64
.It
ARM 32 (ARM-v5, ARM-v7 and Thumb2 instruction sets)
.It
Intel-x86 32
.It
MIPS 32 (III, R1)
.It
MIPS 64 (III, R1)
.It
PowerPC 32
.It
PowerPC 64
.It
SPARC 32
.El
.Pp
.Nm
supports all architectures listed above.
.Pp
.Nm
is also available as a module in modular kernels.
.Sh SYSCTLS
The following sysctl is available when
.Nm
is enabled:
.Bl -tag -width "XnetXbpfXjitXX"
.It Li net.bpf.jit
Toggle
.Sy Just-In-Time
compilation of new filter programs.
Changing a value of this sysctl doesn't affect
existing filter programs.
.El
.Sh SEE ALSO
.Xr bpf 4 ,
.Xr modload 8
.Pp
.Lk http://sljit.sourceforge.net/ sljit library
.Sh HISTORY
The
.Nm
interface first appeared in
.Nx 7.0 .
.Sh AUTHORS
The
.Nm
code was written by
.An Alexander Nasonov Aq Mt alnsn@NetBSD.org .
.Pp
The
.Nm sljit
library was written by
.An Zoltan Herczeg Aq Mt hzmester@freemail.hu .