Re: CVS commit: src/sys

[Mindaugas Rasiukevicius <rmind%netbsd.org@localhost>]

Hi Alex,

Alexander Nasonov <alnsn%yandex.ru@localhost> wrote:
> Mindaugas Rasiukevicius wrote:
> > > Log Message:
> > > Add BPF JIT compiler, currently supporting amd64 and i386.  Code
> > > obtained from FreeBSD.  Also, make few BPF fixes and simplifications
> > > while here. Note that bpf_jit_enable is false for now.
> 
> I wonder why do you want to generate code yourself while you could use
> some jit library? I've almost finished my bpfjit library, I just need
> one or two weekends to clean up all mess I made in my local tree while
> trying to figure out the best way to integrate my changes into the tree.
> Unfortunately, my day job keeps me busy.

The code from FreeBSD is pretty small and simple.  It is also mature and
more widely tested.

If we decide to have a generic JIT compiler, like sljit, I think BPF can
just be converted to use that.  However, sljit is larger and the library
is not straightforward to use for in-kernel compilation.

Do we need a generic JIT compiler, though?

> > FYI:
> > 
> > FreeBSD has quite comprehensive regression tests for BPF.  With some
> > changes they run on NetBSD.
> 
> I have tests too. See https://github.com/alnsn/bpfjit
> 
> Alex

-- 
Mindaugas