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Date: Thu, 9 Dec 2004 17:44:57 +0000
From: "Christian S.J. Peron" <csjp@FreeBSD.org>
To: Gleb Smirnoff <glebius@FreeBSD.org>
Message-ID: <20041209174457.GA82542@freefall.freebsd.org>
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Subject: Re: cvs commit: src/sys/netinet ip_fw_pfil.c
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On Thu, Dec 09, 2004 at 04:41:47PM +0000, Gleb Smirnoff wrote:
> glebius     2004-12-09 16:41:47 UTC
> 
>   FreeBSD src repository
> 
>   Modified files:
>     sys/netinet          ip_fw_pfil.c 
>   Log:
>   Check that DUMMYNET_LOADED before seeking dummynet m_tag.

I think Sam had some reservations about doing this before, We had some
discussions and in the end it was pretty much concluded that since
tags are rarely present, and m_tag_locate is only called if tags are present,
adding this check unconditionally added a memory write and a compare
for every packet.

This change may be a mistake unless you can prove some significant performance gain.

-- 
Christian S.J. Peron
csjp@FreeBSD.ORG
FreeBSD Committer