[dpdk-dev] [PATCH v4] doc: update flow non-cached mode notes

[Bing Zhao <bingz@mellanox.com>]

This patch updates the MLX5 PMD and release notes documentations.
Adding the notes of the behavior change that rte flows organization
is switched into non-cached mode for applications.

Signed-off-by: Bing Zhao <bingz@mellanox.com>
Acked-by: Ori Kam <orika@mellanox.com>
---
v2: update the description in release notes.
v3: update the notes of rte_flow for application.
v4: update the descriptions.
---
 doc/guides/nics/mlx5.rst               | 14 ++++++++++++++
 doc/guides/rel_notes/release_20_05.rst |  1 +
 2 files changed, 15 insertions(+)

diff --git a/doc/guides/nics/mlx5.rst b/doc/guides/nics/mlx5.rst
index 759d0ac..64822ae 100644
--- a/doc/guides/nics/mlx5.rst
+++ b/doc/guides/nics/mlx5.rst
@@ -1290,6 +1290,7 @@ Supported hardware offloads
 
 Notes for metadata
 ------------------
+
 MARK and META items are interrelated with datapath - they might move from/to
 the applications in mbuf fields. Hence, zero value for these items has the
 special meaning - it means "no metadata are provided", not zero values are
@@ -1300,6 +1301,19 @@ set, and we should allow to specify zero values as rte_flow parameters for the
 META and MARK items and actions. In the same time zero mask has no meaning and
 should be rejected on validation stage.
 
+Notes for rte_flow
+------------------
+
+Flows are not cached in the driver. When stopping a device port, all the flows
+created on this port from the application will be flushed automatically in
+the background.
+After stopping the device port, all flows on this port become invalid and
+not represented in the system.
+All references to these flows held by the application should be discarded
+directly but neither destroyed nor flushed.
+
+The application should re-create the flows as required after the port restart.
+
 Notes for testpmd
 -----------------
 
diff --git a/doc/guides/rel_notes/release_20_05.rst b/doc/guides/rel_notes/release_20_05.rst
index 1e5304d..cc53233 100644
--- a/doc/guides/rel_notes/release_20_05.rst
+++ b/doc/guides/rel_notes/release_20_05.rst
@@ -79,6 +79,7 @@ New Features
   * Added support for matching on IPv4 Time To Live and IPv6 Hop Limit.
   * Added support for creating Relaxed Ordering Memory Regions.
   * Added support for jumbo frame size (9K MTU) in Multi-Packet RQ mode.
+  * Removed flow rules caching for memory saving and compliance with ethdev API.
   * Optimized the memory consumption of flow.
 
 * **Updated the Intel ice driver.**
-- 
1.8.3.1