From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Monjalon <thomas.monjalon-pdR9zngts4EAvxtiuMwx3w@public.gmane.org>
Subject: Re: [PATCH 0/3] Vhost app removes dependency of REFCNT
Date: Fri, 24 Oct 2014 11:47:46 +0200
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To: Ouyang Changchun <changchun.ouyang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
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2014-10-24 16:10, Ouyang Changchun:
> To remove the dependency of RTE_MBUF_REFCNT for vhost zero copy,
> the mbuf need introduce EXTERNAL_MBUF(in ol_flags) to indicate it
> attaches to an external buffer, say, from guest space. And don't
> free the external buffer when freeing the mbuf itself in host, in
> addition, RX function in PMD need make sure not overwrite this flag
> when filling ol_flags from descriptors to mbuf.

So you are replacing refcnt by something else which requires special
handling in drivers.
I feel this is not the right design.
Why do you want to remove refcnt dependency?

-- 
Thomas