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Date: Wed, 24 Sep 2008 16:48:43 -0400 (EDT)
From: Steven Rostedt <rostedt@goodmis.org>
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Subject: Re: [RFC PATCH 1/3] Unified trace buffer
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On Wed, 24 Sep 2008, David Miller wrote:

> From: Linus Torvalds <torvalds@linux-foundation.org>
> Date: Wed, 24 Sep 2008 13:23:47 -0700 (PDT)
> 
> > So I'd like the thing to have small headers, and be designed from the 
> > start to have small headers.
> 
> Small headers are good, but I'd suggest making sure there is an
> "offset" or similar field in there.
> 
> Not that I want to encourage frequent changes to header layout, but if
> you do need to add something, then this offset field allows you to do
> so while keeping existing analysis tools working.  They will just
> ignore the new information in the headers, but they will still be able
> to get at the data bits using the offset.

Right now I have a "length" field when fixed_length is not specified. This 
length is currently offest by 8 leaving all 8 bytes aligned.

We could change this to be variable? Would that help you?

-- Steve