1 .. SPDX-License-Identifier: BSD-3-Clause
2 Copyright 2018 The DPDK contributors
4 ABI and API Deprecation
5 =======================
7 See the guidelines document for details of the :doc:`ABI policy
8 <../contributing/abi_policy>`. API and ABI deprecation notices are to be posted
14 * make: Support for building DPDK with "make" has been deprecated and
15 support will be removed in the 20.11 release. From 20.11 onwards, DPDK
16 should be built using meson and ninja. For basic instructions see the
17 `Quick-start Guide <https://core.dpdk.org/doc/quick-start/>`_ on the
18 website or the `Getting Started Guide
19 <https://doc.dpdk.org/guides/linux_gsg/build_dpdk.html>`_ document.
21 * meson: The minimum supported version of meson for configuring and building
22 DPDK will be increased to v0.47.1 (from 0.41) from DPDK 19.05 onwards. For
23 those users with a version earlier than 0.47.1, an updated copy of meson
24 can be got using the ``pip``, or ``pip3``, tool for downloading python
27 * kvargs: The function ``rte_kvargs_process`` will get a new parameter
28 for returning key match count. It will ease handling of no-match case.
30 * eal: To be more inclusive in choice of naming, the DPDK project
31 will replace uses of master/slave in the API's and command line arguments.
33 References to master/slave in relation to lcore will be renamed
34 to initial/worker. The function ``rte_get_master_lcore()``
35 will be renamed to ``rte_get_initial_lcore()``.
36 For the 20.11 release, both names will be present and the
37 old function will be marked with the deprecated tag.
38 The old function will be removed in a future version.
40 The iterator for worker lcores will also change:
41 ``RTE_LCORE_FOREACH_SLAVE`` will be replaced with
42 ``RTE_LCORE_FOREACH_WORKER``.
44 The ``master-lcore`` argument to testpmd will be replaced
45 with ``initial-lcore``. The old ``master-lcore`` argument
46 will produce a runtime notification in 20.11 release, and
47 be removed completely in a future release.
49 * eal: The function ``rte_eal_remote_launch`` will return new error codes
50 after read or write error on the pipe, instead of calling ``rte_panic``.
52 * eal: The ``rte_logs`` struct and global symbol will be made private to
53 remove it from the externally visible ABI and allow it to be updated in the
56 * eal: The ``rte_dev_event`` structure will be made private to the EAL as no
57 public API makes use of it.
59 * rte_atomicNN_xxx: These APIs do not take memory order parameter. This does
60 not allow for writing optimized code for all the CPU architectures supported
61 in DPDK. DPDK will adopt C11 atomic operations semantics and provide wrappers
62 using C11 atomic built-ins. These wrappers must be used for patches that
63 need to be merged in 20.08 onwards. This change will not introduce any
64 performance degradation.
66 * rte_smp_*mb: These APIs provide full barrier functionality. However, many
67 use cases do not require full barriers. To support such use cases, DPDK will
68 adopt C11 barrier semantics and provide wrappers using C11 atomic built-ins.
69 These wrappers must be used for patches that need to be merged in 20.08
70 onwards. This change will not introduce any performance degradation.
72 * rte_cio_*mb: Since the IO barriers for ARMv8 platforms are relaxed from DSB
73 to DMB, rte_cio_*mb APIs provide the same functionality as rte_io_*mb
74 APIs (taking all platforms into consideration). rte_io_*mb APIs should be
75 used in the place of rte_cio_*mb APIs. The rte_cio_*mb APIs will be
76 deprecated in 20.11 release.
78 * igb_uio: In the view of reducing the kernel dependency from the main tree,
79 as a first step, the Technical Board decided to move ``igb_uio``
80 kernel module to the dpdk-kmods repository in the /linux/igb_uio/ directory
82 Minutes of Technical Board Meeting of `2019-11-06
83 <https://mails.dpdk.org/archives/dev/2019-November/151763.html>`_.
85 * lib: will fix extending some enum/define breaking the ABI. There are multiple
86 samples in DPDK that enum/define terminated with a ``.*MAX.*`` value which is
87 used by iterators, and arrays holding these values are sized with this
88 ``.*MAX.*`` value. So extending this enum/define increases the ``.*MAX.*``
89 value which increases the size of the array and depending on how/where the
90 array is used this may break the ABI.
91 ``RTE_ETH_FLOW_MAX`` is one sample of the mentioned case, adding a new flow
92 type will break the ABI because of ``flex_mask[RTE_ETH_FLOW_MAX]`` array
93 usage in following public struct hierarchy:
94 ``rte_eth_fdir_flex_conf -> rte_fdir_conf -> rte_eth_conf (in the middle)``.
95 Need to identify this kind of usages and fix in 20.11, otherwise this blocks
96 us extending existing enum/define.
97 One solution can be using a fixed size array instead of ``.*MAX.*`` value.
99 * pci: The PCI resources map API (``pci_map_resource`` and
100 ``pci_unmap_resource``) was not abstracting the Unix mmap flags (see the
101 workaround for Windows support implemented in the commit
102 9d2b24593724 ("pci: keep API compatibility with mmap values")).
103 This API will be removed from the public API in 20.11 and moved to the PCI
104 bus driver along with the PCI resources lists and associated structures
105 (``pci_map``, ``pci_msix_table``, ``mapped_pci_resource`` and
106 ``mapped_pci_res_list``).
107 With this removal, there won't be a need for the mentioned workaround which
110 * pci: The ``rte_kernel_driver`` enum defined in rte_dev.h will be made private
111 to the PCI subsystem as it is used only by the PCI bus driver and PCI
113 The associated field ``kdrv`` in the ethdev ``rte_eth_dev_data`` structure
114 will be removed as it gave no useful abstracted information to the
115 applications and had no user (neither internal nor external).
117 * mbuf: Some fields will be converted to dynamic API in DPDK 20.11
118 in order to reserve more space for the dynamic fields, as explained in
119 `this presentation <https://www.youtube.com/watch?v=Ttl6MlhmzWY>`_.
120 The following static fields will be moved as dynamic:
123 - ``userdata`` / ``udata64``
126 As a consequence, the layout of the ``struct rte_mbuf`` will be re-arranged,
127 avoiding impact on vectorized implementation of the driver datapaths,
128 while evaluating performance gains of a better use of the first cache line.
130 The deprecated unioned fields ``buf_physaddr`` and ``refcnt_atomic``
131 (as explained below) will be removed in DPDK 20.11.
133 * mbuf: ``refcnt_atomic`` member in structures ``rte_mbuf`` and
134 ``rte_mbuf_ext_shared_info`` is of type ``rte_atomic16_t``.
135 Due to adoption of C11 atomic builtins, the field ``refcnt_atomic``
136 will be replaced with ``refcnt`` of type ``uint16_t`` in DPDK 20.11.
138 * ethdev: Split the ``struct eth_dev_ops`` struct to hide it as much as possible
139 will be done in 20.11.
140 Currently the ``struct eth_dev_ops`` struct is accessible by the application
141 because some inline functions, like ``rte_eth_tx_descriptor_status()``,
142 access the struct directly.
143 The struct will be separate in two, the ops used by inline functions will be
144 moved next to Rx/Tx burst functions, rest of the ``struct eth_dev_ops`` struct
145 will be moved to header file for drivers to hide it from applications.
147 * ethdev: the legacy filter API, including
148 ``rte_eth_dev_filter_supported()``, ``rte_eth_dev_filter_ctrl()`` as well
149 as filter types MACVLAN, ETHERTYPE, FLEXIBLE, SYN, NTUPLE, TUNNEL, FDIR,
150 HASH and L2_TUNNEL, is superseded by the generic flow API (rte_flow) in
151 PMDs that implement the latter.
152 The legacy API will be removed in DPDK 20.11.
154 * ethdev: The flow director API, including ``rte_eth_conf.fdir_conf`` field,
155 and the related structures (``rte_fdir_*`` and ``rte_eth_fdir_*``),
156 will be removed in DPDK 20.11.
158 * ethdev: The legacy L2 tunnel filtering API is deprecated as the rest of
159 the legacy filtering API.
160 The functions ``rte_eth_dev_l2_tunnel_eth_type_conf`` and
161 ``rte_eth_dev_l2_tunnel_offload_set`` which were not marked as deprecated,
162 will be removed in DPDK 20.11.
164 * ethdev: Update API functions returning ``void`` to return ``int`` with
165 negative errno values to indicate various error conditions (e.g.
166 invalid port ID, unsupported operation, failed operation):
168 - ``rte_eth_dev_stop``
169 - ``rte_eth_dev_close``
171 * ethdev: The temporary flag RTE_ETH_DEV_CLOSE_REMOVE will be removed in 20.11.
172 As a consequence, the new behaviour introduced in 18.11 will be effective
173 for all drivers: generic port resources are freed on close operation.
174 Private resources are expected to be released in the ``dev_close`` callback.
175 More details in http://inbox.dpdk.org/dev/5248162.j6AOsuQRmx@thomas/
177 * ethdev: New offload flags ``DEV_RX_OFFLOAD_FLOW_MARK`` will be added in 19.11.
178 This will allow application to enable or disable PMDs from updating
179 ``rte_mbuf::hash::fdir``.
180 This scheme will allow PMDs to avoid writes to ``rte_mbuf`` fields on Rx and
181 thereby improve Rx performance if application wishes do so.
182 In 19.11 PMDs will still update the field even when the offload is not
185 * ethdev: Add new fields to ``rte_eth_rxconf`` to configure the receiving
186 queues to split ingress packets into multiple segments according to the
187 specified lengths into the buffers allocated from the specified
188 memory pools. The backward compatibility to existing API is preserved.
190 * ethdev: ``rx_descriptor_done`` dev_ops and ``rte_eth_rx_descriptor_done``
191 will be deprecated in 20.11 and will be removed in 21.11.
192 Existing ``rte_eth_rx_descriptor_status`` and ``rte_eth_tx_descriptor_status``
193 APIs can be used as replacement.
195 * ethdev: The port mirroring API can be replaced with a more fine grain flow API.
196 The structs ``rte_eth_mirror_conf``, ``rte_eth_vlan_mirror`` and the functions
197 ``rte_eth_mirror_rule_set``, ``rte_eth_mirror_rule_reset`` will be marked
198 as deprecated in DPDK 20.11, along with the associated macros ``ETH_MIRROR_*``.
199 This API will be fully removed in DPDK 21.11.
201 * ethdev: The ``struct rte_flow_item_eth`` and ``struct rte_flow_item_vlan``
202 structs will be modified, to include an additional value, indicating existence
203 or absence of a VLAN header following the current header, as proposed in RFC
204 https://mails.dpdk.org/archives/dev/2020-August/177536.html.
206 * ethdev: The ``struct rte_flow_item_ipv6`` struct will be modified to include
207 additional values, indicating existence or absence of IPv6 extension headers
208 following the IPv6 header, as proposed in RFC
209 https://mails.dpdk.org/archives/dev/2020-August/177257.html.
211 * ethdev: Some internal APIs for driver usage are exported in the .map file.
212 Now DPDK has ``__rte_internal`` marker so we can mark internal APIs and move
213 them to the INTERNAL block in .map. Although these APIs are internal it will
214 break the ABI checks, that is why change is planned for 20.11.
215 The list of internal APIs are mainly ones listed in ``rte_ethdev_driver.h``.
217 * traffic manager: All traffic manager API's in ``rte_tm.h`` were mistakenly made
218 ABI stable in the v19.11 release. The TM maintainer and other contributors have
219 agreed to keep the TM APIs as experimental in expectation of additional spec
220 improvements. Therefore, all APIs in ``rte_tm.h`` will be marked back as
221 experimental in v20.11 DPDK release. For more details, please see `the thread
222 <https://mails.dpdk.org/archives/dev/2020-April/164970.html>`_.
224 * pmd_dpaa: The API ``rte_pmd_dpaa_set_tx_loopback`` will have extended
225 ``port_id`` definition from ``uint8_t`` to ``uint16_t``.
227 * security: The API ``rte_security_session_create`` takes only single mempool
228 for session and session private data. So the application need to create
229 mempool for twice the number of sessions needed and will also lead to
230 wastage of memory as session private data need more memory compared to session.
231 Hence the API will be modified to take two mempool pointers - one for session
232 and one for private data.
234 * cryptodev: ``RTE_CRYPTO_AEAD_LIST_END`` from ``enum rte_crypto_aead_algorithm``,
235 ``RTE_CRYPTO_CIPHER_LIST_END`` from ``enum rte_crypto_cipher_algorithm`` and
236 ``RTE_CRYPTO_AUTH_LIST_END`` from ``enum rte_crypto_auth_algorithm``
239 * cryptodev: support for using IV with all sizes is added, J0 still can
240 be used but only when IV length in following structs ``rte_crypto_auth_xform``,
241 ``rte_crypto_aead_xform`` is set to zero. When IV length is greater or equal
242 to one it means it represents IV, when is set to zero it means J0 is used
243 directly, in this case 16 bytes of J0 need to be passed.
245 * eventdev: Following structures will be modified to support DLB PMD
246 and future extensions:
248 - ``rte_event_dev_info``
249 - ``rte_event_dev_config``
250 - ``rte_event_port_conf``
252 Patches containing justification, documentation, and proposed modifications
255 - https://patches.dpdk.org/patch/71457/
256 - https://patches.dpdk.org/patch/71456/
258 * rawdev: The rawdev APIs which take a device-specific structure as
259 parameter directly, or indirectly via a "private" pointer inside another
260 structure, will be modified to take an additional parameter of the
261 structure size. The affected APIs will include ``rte_rawdev_info_get``,
262 ``rte_rawdev_configure``, ``rte_rawdev_queue_conf_get`` and
263 ``rte_rawdev_queue_setup``.
265 * acl: ``RTE_ACL_CLASSIFY_NUM`` enum value will be removed.
266 This enum value is not used inside DPDK, while it prevents to add new
267 classify algorithms without causing an ABI breakage.
269 * sched: To allow more traffic classes, flexible mapping of pipe queues to
270 traffic classes, and subport level configuration of pipes and queues
271 changes will be made to macros, data structures and API functions defined
272 in "rte_sched.h". These changes are aligned to improvements suggested in the
273 RFC https://mails.dpdk.org/archives/dev/2018-November/120035.html.
275 * metrics: The function ``rte_metrics_init`` will have a non-void return
276 in order to notify errors instead of calling ``rte_exit``.
278 * power: ``rte_power_set_env`` function will no longer return 0 on attempt
279 to set new power environment if power environment was already initialized.
280 In this case the function will return -1 unless the environment is unset first
281 (using ``rte_power_unset_env``). Other function usage scenarios will not change.
283 * python: Since the beginning of 2020, Python 2 has officially reached
284 end-of-support: https://www.python.org/doc/sunset-python-2/.
285 Python 2 support will be completely removed in 20.11.
286 In 20.08, explicit deprecation warnings will be displayed when running
287 scripts with Python 2.
289 * dpdk-setup.sh: This old script relies on deprecated stuff, and especially
290 ``make``. Given environments are too much variables for such a simple script,
291 it will be removed in DPDK 20.11.
292 Some useful parts may be converted into specific scripts.