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From: Darren Reed <avalon@coombs.anu.edu.au>
Subject: Re: ipretard.c selective tcp/ip queues and throughput limiters
To: terry@lambert.org (Terry Lambert)
Date: Thu, 2 Jan 1997 21:42:04 +1100 (EDT)
Cc: avalon@coombs.anu.edu.au, terry@lambert.org, julian@whistle.com,
        luigi@labinfo.iet.unipi.it, proff@iq.org, danny@panda.hilink.com.au,
        hackers@freebsd.org
In-Reply-To: <199612310244.TAA01346@phaeton.artisoft.com> from "Terry Lambert" at Dec 30, 96 07:44:14 pm
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In some mail from Terry Lambert, sie said:
> 
> > > This is what I've been calling "layering problems".  It is definitely
> > > a goal of mine to allow a module to be debugged in user space with a
> > > source level debugger.
> > 
> > Making code that compiles in the kernel also compile for user programs
> > is tricky if you only want _one_ routine for both.
> 
> I beg to disagree... PIC objects don't care whose address space
> they are loaded or copied into... code is relatively addressed and
> doesn't really care post-relocation if the relocation was by way
> of ld -A or by way of dlopen.

However, some simple functions such as malloc() are *much* different when
compiled for kernel vs user.

You can't compile a routine in user-space that uses mbufs without doing
some extra work.  Then you have to deal with spl's that don't exist, etc.

And so on.

I was thinking about this the other day and wondered how easy would it be
to make the kernel compile as a user process ?

Darren