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Date: Mon, 21 Nov 2011 16:39:20 +1100
From: Lawrence Stewart <lstewart@freebsd.org>
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To: Ben Kaduk <minimarmot@gmail.com>
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Cc: svn-src-head@FreeBSD.org, svn-src-all@FreeBSD.org,
	src-committers@FreeBSD.org, Julien Ridoux <jridoux@unimelb.edu.au>
Subject: Re: svn commit: r227778 - head/sys/net
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On 11/21/11 16:12, Ben Kaduk wrote:
> On Sun, Nov 20, 2011 at 11:17 PM, Lawrence Stewart<lstewart@freebsd.org>  wrote:
>> Author: lstewart
>> Date: Mon Nov 21 04:17:24 2011
>> New Revision: 227778
>> URL: http://svn.freebsd.org/changeset/base/227778
>>
>> Log:
>>   - When feed-forward clock support is compiled in, change the BPF header to
>>     contain both a regular timestamp obtained from the system clock and the
>>     current feed-forward ffcounter value. This enables new possibilities including
>
> Is it really necessary to make the ABI dependent on a kernel
> configuration option?  This causes all sorts of headaches if loadable
> modules ever want to use that ABI, something that we just ran into
> with vm_page_t and friends and had a long thread on -current about.

Fair question. Julien, if pcap and other consumers will happily ignore 
the new ffcount_stamp member in the bpf header, is there any reason to 
conditionally add the ffcounter into the header struct?

Cheers,
Lawrence