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Date: Mon, 19 Apr 2004 12:28:23 -0700 (PDT)
From: Julian Elischer <julian@elischer.org>
To: Luigi Rizzo <rizzo@icir.org>
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cc: net@freebsd.org
Subject: Re: what is the story on if_index allocation ?
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>From memory,

It's completely un-needed except that some standards want to access 
interfaces by index for statitics purposes.


On Mon, 19 Apr 2004, Luigi Rizzo wrote:

> 
> I am a bit unclear -- how do we allocate if_index values for
> network interfaces ?
> I thought the strategy was allocate them sequentially, and
> only reuse numbers at the top of the allocated range.
> But then i see if_findindex() is quite complicated, and
> seems to look for hints using resource_string_value() and
> resource_find_dev() to possibly recycle old indexes below
> if_index.
> 
> Can someone explain what is the goal ? Reuse a number if an
> interface has the same name of a previously existing one and
> the index is free ? And does it make sense, anyways, or
> we could just simplify that code and just reuse the first
> available entry in ifindex_table[] ?
> Even the current allocation strategy does not guarantee that
> indexes reflect the order of creation of interfaces, if that
> is what we care about.
> 
> 	cheers
> 	luigi
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