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Date: Sun, 16 Mar 2014 03:08:33 +0430
From: Hooman Fazaeli <hoomanfazaeli@gmail.com>
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To: Rui Paulo <rpaulo@FreeBSD.org>
Subject: Re: mbuf question
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On 3/15/2014 9:09 PM, Rui Paulo wrote:
> On 15 Mar 2014, at 00:48, Hooman Fazaeli <hoomanfazaeli@gmail.com> wrote:
>> What about the area started at (m->m_ext + 1) whose size is (MHLEN - sizeof(struct m_ext))?
>> Is there any known uses of this area in the stack?
> I'm not sure what you mean by m_ext + 1, but what are you trying to do?  If you need to tag an mbuf, use mbuf tags.
>
> --
> Rui Paulo

(m->m_ext+ 1) points to the (unused?) area in m->m_dat.MHright after the space occupied by m_ext.
I am well aware of mbuf tags. I was just thinking toavoid the overhead of m_tag allocation/de-allocation
and store my little piece of data directly in mbufs.

-- 

Best regards.
Hooman Fazaeli