The AVX512-optimized datapath features, including DPCLS lookups, action handling, miniflow extraction, and DPIF input processing, are being deprecated.
These features have not been actively maintained upstream and there is no automated testing coverage for them. This notice deprecates support as of the v3.7 release, with the intention to remove it in the v3.8 release. Signed-off-by: Eelco Chaudron <[email protected]> --- Documentation/intro/install/dpdk.rst | 4 ++++ Documentation/topics/dpdk/bridge.rst | 25 +++++++++++++++++++++++++ Documentation/topics/testing.rst | 4 ++++ NEWS | 5 +++++ acinclude.m4 | 8 ++++++++ 5 files changed, 46 insertions(+) diff --git a/Documentation/intro/install/dpdk.rst b/Documentation/intro/install/dpdk.rst index af824239e..731a1ccc4 100644 --- a/Documentation/intro/install/dpdk.rst +++ b/Documentation/intro/install/dpdk.rst @@ -155,6 +155,10 @@ has to be configured to build against the DPDK library (``--with-dpdk``). While ``--with-dpdk`` is required, you can pass any other configuration option described in :ref:`general-configuring`. + .. note:: + The AVX512 Datapath Classifier Performance feature is deprecated and will + be removed in a future release. + It is strongly recommended to build OVS with at least ``-msse4.2`` and ``-mpopcnt`` optimization flags. If these flags are not enabled, the AVX512 optimized DPCLS implementation is not available in the resulting binary. diff --git a/Documentation/topics/dpdk/bridge.rst b/Documentation/topics/dpdk/bridge.rst index a077385e9..03c4dd4e3 100644 --- a/Documentation/topics/dpdk/bridge.rst +++ b/Documentation/topics/dpdk/bridge.rst @@ -165,6 +165,11 @@ To turn on SMC:: Datapath Classifier Performance ------------------------------- +.. note:: + + The AVX512 Datapath Classifier Performance feature is deprecated and will be + removed in a future release. + The datapath classifier (dpcls) performs wildcard rule matching, a compute intensive process of matching a packet ``miniflow`` to a rule ``miniflow``. The code that does this compute work impacts datapath performance, and optimizing @@ -214,6 +219,11 @@ result in lower performance when these mitigations are enabled. Optimizing Specific Subtable Search ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +.. note:: + + The AVX512 Optimizing Specific Subtable Search feature is deprecated and + will be removed in a future release. + During the packet classification, the datapath can use specialized lookup tables to optimize the search. However, not all situations are optimized. If you see a message like the following one in the OVS logs, it means that there @@ -247,6 +257,11 @@ the output of the ``dp-extra-info:miniflow_bits(4,1)`` values. Datapath Interface Performance ------------------------------ +.. note:: + + The AVX512 Datapath Interface Performance feature is deprecated and will be + removed in a future release. + The datapath interface (DPIF) is responsible for taking packets through the major components of the userspace datapath; such as packet parsing, caches and datapath classifier lookups. @@ -274,6 +289,11 @@ name:: Packet parsing performance -------------------------- +.. note:: + + The AVX512 Packet parsing performance feature is deprecated and will be + removed in a future release. + Open vSwitch performs parsing of the raw packets and extracts the important header information into a compressed miniflow structure. This miniflow is composed of bits and blocks where the bits signify which blocks are set or have @@ -331,6 +351,11 @@ following command:: Actions Implementations (Experimental) -------------------------------------- +.. note:: + + The AVX512 Actions Implementations feature is deprecated and will be + removed in a future release. + Actions describe what processing or modification should be performed on a packet when it matches a given flow. Similar to the datapath interface, DPCLS and MFEX (see above), the implementation of these actions can be diff --git a/Documentation/topics/testing.rst b/Documentation/topics/testing.rst index dbeaf2d93..ca6c9f2a0 100644 --- a/Documentation/topics/testing.rst +++ b/Documentation/topics/testing.rst @@ -366,6 +366,10 @@ testsuite. Userspace datapath: Testing and Validation of CPU-specific Optimizations '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' +.. note:: + The AVX512 CPU-specific optimization features are deprecated and will be + removed in a future release. + As multiple versions of the datapath classifier, packet parsing functions and actions can co-exist, each with different CPU ISA optimizations, it is important to validate that they all give the exact same results. To easily diff --git a/NEWS b/NEWS index f9a74df1a..216b25604 100644 --- a/NEWS +++ b/NEWS @@ -16,6 +16,11 @@ Post-v3.6.0 * New ovsdb_idl_txn_assert_read_only() interface to mark transactions as read-only and trigger assertion failure when application attempts to modify the database data through this transaction. + - The following AVX512-specific features are now deprecated: + * AVX512-optimized DPCLS lookups. + * AVX512-optimized action handling. + * AVX512-optimized miniflow extraction. + * AVX512-optimized DPIF input processing. v3.6.0 - 18 Aug 2025 diff --git a/acinclude.m4 b/acinclude.m4 index 369e37eae..adbe62c40 100644 --- a/acinclude.m4 +++ b/acinclude.m4 @@ -30,6 +30,8 @@ AC_DEFUN([OVS_CHECK_ACTIONS_AUTOVALIDATOR], [ AC_DEFINE([ACTIONS_AUTOVALIDATOR_DEFAULT], [1], [Autovalidator for actions is a default implementation.]) AC_MSG_RESULT([yes]) + AC_MSG_WARN( + [Explicit AVX512 feature support will be deprecated in the next release.]) fi ]) @@ -50,6 +52,8 @@ AC_DEFUN([OVS_CHECK_MFEX_AUTOVALIDATOR], [ AC_DEFINE([MFEX_AUTOVALIDATOR_DEFAULT], [1], [Autovalidator for miniflow_extract is a default implementation.]) AC_MSG_RESULT([yes]) + AC_MSG_WARN( + [Explicit AVX512 feature support will be deprecated in the next release.]) fi ]) @@ -70,6 +74,8 @@ AC_DEFUN([OVS_CHECK_DPCLS_AUTOVALIDATOR], [ [Autovalidator for the userspace datapath classifier is a default implementation.]) AC_MSG_RESULT([yes]) + AC_MSG_WARN( + [Explicit AVX512 feature support will be deprecated in the next release.]) fi ]) @@ -88,6 +94,8 @@ AC_DEFUN([OVS_CHECK_DPIF_AVX512_DEFAULT], [ [DPIF AVX512 is a default implementation of the userspace datapath interface.]) AC_MSG_RESULT([yes]) + AC_MSG_WARN( + [Explicit AVX512 feature support will be deprecated in the next release.]) fi ]) -- 2.50.1 _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
