------------------
#. Major ABI versions are declared no more frequently than yearly. Compatibility
- with the major ABI version is mandatory in subsequent releases until a new
- major ABI version is declared.
+ with the major ABI version is mandatory in subsequent releases until a
+ :ref:`new major ABI version <new_abi_version>` is declared.
#. Major ABI versions are usually but not always declared aligned with a
:ref:`LTS release <stable_lts_releases>`.
#. The ABI version is managed at a project level in DPDK, and is reflected in
#. The removal of symbols is considered an :ref:`ABI breakage <abi_breakages>`,
once approved these will form part of the next ABI version.
#. Libraries or APIs marked as :ref:`experimental <experimental_apis>` may
- change without constraint, as they are not considered part of an ABI version.
- Experimental libraries have the major ABI version ``0``.
+ be changed or removed without prior notice, as they are not considered part
+ of an ABI version.
#. Updates to the :ref:`minimum hardware requirements <hw_rqmts>`, which drop
support for hardware which was previously supported, should be treated as an
ABI change.
.. note::
- In 2019, the DPDK community stated its intention to move to ABI stable
- releases, over a number of release cycles. This change begins with
- maintaining ABI stability through one year of DPDK releases starting from
- DPDK 19.11. This policy will be reviewed in 2020, with intention of
- lengthening the stability period. Additional implementation detail can be
- found in the :ref:`release notes <20_02_abi_changes>`.
+ Please note that this policy does not currently apply to the
+ :doc:`Windows build <../windows_gsg/intro>`.
What is an ABI?
~~~~~~~~~~~~~~~
The following are examples of allowable ABI changes occurring between
declarations of major ABI versions.
-* DPDK 19.11 release, defines the function ``rte_foo()``, and ``rte_foo()``
- as part of the major ABI version ``20``.
+* DPDK 19.11 release defines the function ``rte_foo()`` ; ``rte_foo()``
+ is part of the major ABI version ``20``.
-* DPDK 20.02 release defines a new function ``rte_foo(uint8_t bar)``, and
- this is not a problem as long as the symbol ``rte_foo@DPDK20`` is
+* DPDK 20.02 release defines a new function ``rte_foo(uint8_t bar)``.
+ This is not a problem as long as the symbol ``rte_foo@DPDK20`` is
preserved through :ref:`abi_versioning`.
- The new function may be marked with the ``__rte_experimental`` tag for a
number of releases, as described in the section :ref:`experimental_apis`.
- - Once ``rte_foo(uint8_t bar)`` becomes non-experimental ``rte_foo()`` is then
- declared as ``__rte_depreciated``, with an associated deprecation notice
- provided.
+ - Once ``rte_foo(uint8_t bar)`` becomes non-experimental, ``rte_foo()`` is
+ declared as ``__rte_deprecated`` and an deprecation notice is provided.
* DPDK 19.11 is not re-released to include ``rte_foo(uint8_t bar)``, the new
version of ``rte_foo`` only exists from DPDK 20.02 onwards as described in the
rte_baz()``. This function may or may not exist in the DPDK 20.05 release.
* An application ``dPacket`` wishes to use ``rte_foo(uint8_t bar)``, before the
- declaration of the DPDK ``21`` major API version. The application can only
+ declaration of the DPDK ``21`` major ABI version. The application can only
ensure its runtime dependencies are met by specifying ``DPDK (>= 20.2)`` as
- an explicit package dependency, as the soname only may only indicate the
+ an explicit package dependency, as the soname can only indicate the
supported major ABI version.
* At the release of DPDK 20.11, the function ``rte_foo(uint8_t bar)`` becomes
- formally part of then new major ABI version DPDK 21.0 and ``rte_foo()`` may be
+ formally part of then new major ABI version DPDK ``21`` and ``rte_foo()`` may be
removed.
.. _deprecation_notices:
these changes. Binaries using this library built prior to ABI version 21 will
require updating and recompilation.
+
+.. _new_abi_version:
+
+New ABI versions
+------------------
+
+A new ABI version may be declared aligned with a given release.
+The requirement to preserve compatibility with the previous major ABI version
+is then dropped for the duration of this release cycle.
+This is commonly known as the *ABI breakage window*,
+and some amended rules apply during this cycle:
+
+ * The requirement to preserve compatibility with the previous major ABI
+ version, as described in the section :ref:`abi_changes` does not apply.
+ * Contributors of compatibility preserving code in previous releases,
+ are now required to remove this compatibility code,
+ as described in the section :ref:`abi_changes`.
+ * Symbol versioning references to the old ABI version are updated
+ to reference the new ABI version,
+ as described in the section :ref:`deprecating_entire_abi`.
+ * Contributors of aliases to experimental in previous releases,
+ as described in section :ref:`aliasing_experimental_symbols`,
+ are now required to remove these aliases.
+ * Finally, the *ABI breakage window* is *not* permission to circumvent
+ the other aspects of the procedures to make ABI changes
+ described in :ref:`abi_changes`, that is, 3 ACKs of the requirement
+ to break the ABI and the observance of a deprecation notice
+ are still considered mandatory.
+
.. _experimental_apis:
Experimental
~~~~
APIs marked as ``experimental`` are not considered part of an ABI version and
-may change without warning at any time. Since changes to APIs are most likely
+may be changed or removed without prior notice. Since changes to APIs are most likely
immediately after their introduction, as users begin to take advantage of those
new APIs and start finding issues with them, new DPDK APIs will be automatically
marked as ``experimental`` to allow for a period of stabilization before they
~~~~~~~~~
Libraries marked as ``experimental`` are entirely not considered part of an ABI
-version, and may change without warning at any time. Experimental libraries
-always have a major version of ``0`` to indicate they exist outside of
-:ref:`abi_versioning` , with the minor version incremented with each ABI change
-to library.
+version.
+All functions in such libraries may be changed or removed without prior notice.
git.droids-corp.org / dpdk.git / blobdiff