From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Monjalon <thomas.monjalon@6wind.com>
Subject: Re: [PATCH v2] mbuf: decrease refcnt when detaching
Date: Tue, 17 May 2016 14:43:19 +0200
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To: Hiroyuki Mikita <h.mikita89@gmail.com>, konstantin.ananyev@intel.com
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2016-05-17 01:53, Hiroyuki Mikita:
> The rte_pktmbuf_detach() function should decrease refcnt on a direct
> buffer.
> 
> Signed-off-by: Hiroyuki Mikita <h.mikita89@gmail.com>
> ---
> v2:
> * introduced a new function rte_pktmbuf_detach2() which decrease refcnt.

As you have noticed, "whenever the indirect buffer is detached,
the reference counter on the direct buffer is decremented."
So the current behaviour of rte_pktmbuf_detach() is buggy.
Why not fix it without renaming?
If you consider this behavioral bug is part of the API, we
can fix it in a new function unattach and deprecate detach.
But Konstantin, why do you want to keep a restore function?
What is the need?

Please explicit the function name for the detach operation in
doc/guides/prog_guide/mbuf_lib.rst (whatever detach2 or unattach).

> * marked rte_pktmbuf_detach() as deprecated.
> * added comments about refcnt to rte_pktmbuf_attach() and rte_pktmbuf_detach().
> * checked refcnt when detaching in unit tests.
> * added this issue to release notes.