doc: announce mempool API changes

An API/ABI changes are planned for 18.05 [1]:

 * Allow to customize how mempool objects are stored in memory.
 * Deprecate mempool XMEM API.
 * Add mempool driver ops to get information from mempool driver and
   dequeue contiguous blocks of objects if driver supports it.

[1] http://dpdk.org/ml/archives/dev/2018-January/088698.html

Signed-off-by: Andrew Rybchenko <arybchenko@solarflare.com>
Acked-by: Olivier Matz <olivier.matz@6wind.com>
Acked-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>
Acked-by: Hemant Agrawal <hemant.agrawal@nxp.com>

diff --git a/doc/guides/rel_notes/deprecation.rst b/doc/guides/rel_notes/deprecation.rst
index 730d733..7befd94 100644 (file)
--- a/doc/guides/rel_notes/deprecation.rst
+++ b/doc/guides/rel_notes/deprecation.rst
@@ -59,6 +59,23 @@ Deprecation Notices
 
   - ``rte_eal_mbuf_default_mempool_ops``
 
+* mempool: several API and ABI changes are planned in v18.05.
+  The following functions, introduced for Xen, which is not supported
+  anymore since v17.11, are hard to use, not used anywhere else in DPDK.
+  Therefore they will be deprecated in v18.05 and removed in v18.08:
+
+  - ``rte_mempool_xmem_create``
+  - ``rte_mempool_xmem_size``
+  - ``rte_mempool_xmem_usage``
+
+  The following changes are planned:
+
+  - removal of ``get_capabilities`` mempool ops and related flags.
+  - substitute ``register_memory_area`` with ``populate`` ops.
+  - addition of new ops to customize required memory chunk calculation,
+    customize objects population and allocate contiguous
+    block of objects if underlying driver supports it.
+
 * ethdev: a new Tx and Rx offload API was introduced on 17.11.
   In the new API, offloads are divided into per-port and per-queue offloads.
   Offloads are disabled by default and enabled per application request.