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From: Robert Watson <rwatson@FreeBSD.org>
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Cc: Ryan Stone <rysto32@gmail.com>, FreeBSD Net <net@freebsd.org>
Subject: Re: mbuf changes
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On Thu, 30 Sep 2010, Julian Elischer wrote:

> On 9/30/10 10:49 AM, Ryan Stone wrote:
>> It's not a big thing but it would be nice to replace the m_next and 
>> m_nextpkt fields with queue.h macros.
>> 
> funny, I've never even thought of that..

I have, and it's a massive change touching code all over the kernel in vast 
quantities.  While in principle it's a good idea (consistently avoid 
hand-crafted linked lists), it's something I'd discourage on the basis that it 
probably won't significant reduce the kernel bug count, but will make it even 
harder for vendors with large local changes to the network stack to keep up.

(We might consider revisiting the proposal for 10.0, perhaps?  I'd rather we 
burnt the cycles on fleshing out network stack virtualization more thoroughly 
for 9.x though.)

Robert