Re: RFC: if_clone overhaul
From: Brooks Davis (brooks_at_one-eyed-alien.net)
Date: 04/22/04
- Previous message: Andre Oppermann: "Re: simulating an LFN over 1Gb LAN Ethernet?"
- In reply to: Andre Oppermann: "Re: RFC: if_clone overhaul"
- Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]
Date: Thu, 22 Apr 2004 08:44:51 -0700 To: Andre Oppermann <andre@freebsd.org>
On Thu, Apr 22, 2004 at 04:13:40PM +0200, Andre Oppermann wrote:
> Brooks Davis wrote:
> >
> > Please test/review the following patch to the network interface cloneing
> > code. This code is a major overhaul of the cloning infrastructure.
> >
> > The significant include:
> > - Split the code out into if_clone.[ch].
> > - Locked struct if_clone. Derived from work by Maurycy
> > Pawlowski-Wieronski <maurycy at fouk.org>
> > - Add a per-cloner match function rather then simply matching names of
> > the form <name><unit> and <name>.
> > - Use the match function to allow creation of <interface>.<tag>
> > vlan interfaces. The old way is preserved unchanged!
> > - Also the match function to allow creation of stf(4) interfaces named
> > stf0, stf, or 6to4. This is the only major user visiable change in
> > that "ifconfig stf" creates the interface stf rather then stf0 and
> > does not print "stf0" to stdout.
> > - Allow destroy functions to fail so they can refuse to delete
> > interfaces. Currently, we forbid the deletion of interfaces which
> > were created in the init function, particularly lo0, pflog0, and
> > pfsync0. In the case of lo0 this was a panic implemenation so it
> > does not count as a user visiable change. :-)
> > - Since most interfaces do not need the new functionality, an family of
> > wrapper functions, ifc_simple_*(), were created to wrap old style
> > cloner functions.
> > - The IF_CLONE_INITIALIZER macro is replaced with a new incompatable
> > IFC_CLONE_INITALIZER and ifc_simple consumers use IFC_SIMPLE_DECLARE
> > instead.
> >
> > TODO:
> > - Integrate vlan changes into /etc/rc* (add support for interfaces with
> > '.' in their name).
> > - Document new vlan syntax in vlan(4).
>
> Looks good and I like it! ;-)
>
> Some comments:
>
> o in net/if_clone.h you can remove the 3rd Regents copyright clause.
> o in net/if_clone.c you can remove the 3rd Regents copyright clause.
Done in perforce.
> o in net/if_clone.h, is ## really a legal character in variables?
> Looks strange for sure!
That's the concatenation operator for cpp macros. While it's not
stricly necessicary to use a unique variable name per driver since the
variable is static, it's still a good idea in general. This lets me do
that (it's also why the input is unquoted).
>
> o how far does the cloning code scale? I'm asking because with the
> work on the l2tp stuff you'll get machines with possibly 10'000
> or more ppp over l2tp connections acting as LAC.
The only scaling issue I can think of is that it uses a linearly scanned
bitmap of units to handle unit allocation. You could presumably
optimize this into some sort of a tree if you had poor performance and
sparce allocation. You could also obtain some optimization benefits by
using longs (native word size ints) instead of chars.
-- Brooks
-- Any statement of the form "X is the one, true Y" is FALSE. PGP fingerprint 655D 519C 26A7 82E7 2529 9BF0 5D8E 8BE9 F238 1AD4
- application/pgp-signature attachment: stored
- Previous message: Andre Oppermann: "Re: simulating an LFN over 1Gb LAN Ethernet?"
- In reply to: Andre Oppermann: "Re: RFC: if_clone overhaul"
- Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]
Relevant Pages
|
|
