[PATCH v2 33/33] doc: update release notes about rte_smp_XX removal

[Stephen Hemminger]

The functions rte_smp_XX were previously marked for removal.
The removal is now complete across the tree.

Signed-off-by: Stephen Hemminger <stephen at networkplumber.org>
---
 doc/guides/rel_notes/deprecation.rst   |  8 --------
 doc/guides/rel_notes/release_26_11.rst | 11 +++++++++++
 2 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/doc/guides/rel_notes/deprecation.rst b/doc/guides/rel_notes/deprecation.rst
index 6ad7698c6b..ff0bab60ab 100644
--- a/doc/guides/rel_notes/deprecation.rst
+++ b/doc/guides/rel_notes/deprecation.rst
@@ -46,14 +46,6 @@ Deprecation Notices
   operations must be used for patches that need to be merged in 20.08 onwards.
   This change will not introduce any performance degradation.
 
-* rte_smp_*mb: These APIs provide full barrier functionality. However, many
-  use cases do not require full barriers. To support such use cases, DPDK has
-  adopted atomic operations from
-  https://gcc.gnu.org/onlinedocs/gcc/_005f_005fatomic-Builtins.html. These
-  operations and a new wrapper ``rte_atomic_thread_fence`` instead of
-  ``__atomic_thread_fence`` must be used for patches that need to be merged in
-  20.08 onwards. This change will not introduce any performance degradation.
-
 * mempool: The ``flushthresh`` field in ``struct rte_mempool_cache`` is obsolete,
   and will be removed in DPDK 26.11.
 
diff --git a/doc/guides/rel_notes/release_26_11.rst b/doc/guides/rel_notes/release_26_11.rst
index 4b3e5d995c..c545374b6d 100644
--- a/doc/guides/rel_notes/release_26_11.rst
+++ b/doc/guides/rel_notes/release_26_11.rst
@@ -79,6 +79,17 @@ Removed Items
     ``rte_rib6_is_equal``
   * table: ``RTE_LPM_IPV6_ADDR_SIZE``
 
+* Removed SMP memory barriers:
+
+  * ``rte_smp_mb()`` replaced with ``rte_atomic_thread_fence(rte_memory_order_seq_cst)``
+  * ``rte_smp_rmb()`` replaced with ``rte_atomic_thread_fence(rte_memory_order_acquire)``
+  * ``rte_smp_wmb()`` replaced with ``rte_atomic_thread_fence(rte_memory_order_release)``
+
+  Some call sites became release stores or acquire loads instead of a
+  standalone fence. Barriers that order CPU accesses against a device,
+  rather than against another CPU, should use ``rte_io_wmb()`` and
+  ``rte_io_rmb()`` instead.
+
 
 API Changes
 -----------
-- 
2.53.0