[dpdk-dev] [PATCH v2] doc: add deprecation notice about changes to ethernet structures

[Stephen Hemminger]

Tell users about upcoming changes to rte_ether_addr and
rte_ether_header.

Signed-off-by: Stephen Hemminger <stephen at networkplumber.org>
Acked-by: Bruce Richardson <bruce.richardson at intel.com>
---
v2 - reword and fix spelling

 doc/guides/rel_notes/deprecation.rst | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/doc/guides/rel_notes/deprecation.rst b/doc/guides/rel_notes/deprecation.rst
index a7796f49b9fe..307f831cee60 100644
--- a/doc/guides/rel_notes/deprecation.rst
+++ b/doc/guides/rel_notes/deprecation.rst
@@ -82,3 +82,13 @@ Deprecation Notices
   to set new power environment if power environment was already initialized.
   In this case the function will return -1 unless the environment is unset first
   (using ``rte_power_unset_env``). Other function usage scenarios will not change.
+
+* net: the Ethernet address and header definitions will change
+  attributes. The Ethernet address struct will no longer be marked as
+  packed since the packed attribute is meaningless on a byte
+  array. The Ethernet header will be marked as aligned on a 2-byte
+  boundary and will no longer have the packed attribute. This allows
+  for efficient access on CPU architectures where unaligned access is
+  expensive. These changes should not impact normal usage because drivers
+  naturally align the Ethernet header on receive and all known
+  encapsulations preserve the alignment of the header.
-- 
2.20.1