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Date: Sat, 13 Mar 2010 13:56:57 +0000
From: Bruce Simpson <bms@incunabulum.net>
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To: "Robert N. M. Watson" <rwatson@FreeBSD.org>
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	<2F4A2F84-4955-49C2-B25E-BB987BC27815@lakerest.net>
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Cc: svn-src-head@FreeBSD.org, svn-src-all@FreeBSD.org,
	src-committers@FreeBSD.org, Randall Stewart <rrs@lakerest.net>
Subject: Re: svn commit: r205104 - in head/sys: dev/xen/netback netinet
	netinet6
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On 03/13/10 13:53, Robert N. M. Watson wrote:
> On Mar 13, 2010, at 1:50 PM, Randall Stewart wrote:
>    
>> I could refactor that this way if you want... it would mean a few more de-ref's and
>> looking to see if its a v4 or v6 packet and then doing the proper offset...
>>      

This is the sort of thing which M_PROTO* flags are good for.

Derefs in the hot path should be amortized whenever that makes sense.