[dpdk-dev] [PATCH v2] doc: announce ABI change for mbuf structure

[Olivier Matz]

For 16.11, the mbuf structure will be modified implying ABI breakage.
Some discussions already took place here:
http://www.dpdk.org/dev/patchwork/patch/12878/

Signed-off-by: Olivier Matz <olivier.matz at 6wind.com>
---

v1->v2:
- reword the sentences to keep things more open, as suggested by Bruce

 doc/guides/rel_notes/deprecation.rst | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/doc/guides/rel_notes/deprecation.rst b/doc/guides/rel_notes/deprecation.rst
index f502f86..b9f5a93 100644
--- a/doc/guides/rel_notes/deprecation.rst
+++ b/doc/guides/rel_notes/deprecation.rst
@@ -41,3 +41,9 @@ Deprecation Notices
 * The mempool functions for single/multi producer/consumer are deprecated and
   will be removed in 16.11.
   It is replaced by rte_mempool_generic_get/put functions.
+
+* ABI changes are planned for 16.11 in the ``rte_mbuf`` structure: some fields
+  may be reordered to facilitate the writing of ``data_off``, ``refcnt``, and
+  ``nb_segs`` in one operation, because some platforms have an overhead if the
+  store address is not naturally aligned. Other mbuf fields, such as the
+  ``port`` field, may be moved or removed as part of this mbuf work.
-- 
2.8.1