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 * build macros: The macros defining RTE_MACHINE_CPUFLAG_* will be removed
28 from the build. The information provided by these macros is available
29 through standard compiler macros. For example, RTE_MACHINE_CPUFLAG_SSE3
30 duplicates the compiler-provided macro __SSE3__.
32 * kvargs: The function ``rte_kvargs_process`` will get a new parameter
33 for returning key match count. It will ease handling of no-match case.
35 * eal: To be more inclusive in choice of naming, the DPDK project
36 will replace uses of master/slave in the API's and command line arguments.
38 References to master/slave in relation to lcore will be renamed
39 to initial/worker. The function ``rte_get_master_lcore()``
40 will be renamed to ``rte_get_initial_lcore()``.
41 For the 20.11 release, both names will be present and the
42 old function will be marked with the deprecated tag.
43 The old function will be removed in a future version.
45 The iterator for worker lcores will also change:
46 ``RTE_LCORE_FOREACH_SLAVE`` will be replaced with
47 ``RTE_LCORE_FOREACH_WORKER``.
49 The ``master-lcore`` argument to testpmd will be replaced
50 with ``initial-lcore``. The old ``master-lcore`` argument
51 will produce a runtime notification in 20.11 release, and
52 be removed completely in a future release.
54 * eal: The terms blacklist and whitelist to describe devices used
55 by DPDK will be replaced in the 20.11 relase.
56 This will apply to command line arguments as well as macros.
58 The macro ``RTE_DEV_BLACKLISTED`` will be replaced with ``RTE_DEV_EXCLUDED``
59 and ``RTE_DEV_WHITELISTED`` will be replaced with ``RTE_DEV_INCLUDED``
60 ``RTE_BUS_SCAN_BLACKLIST`` and ``RTE_BUS_SCAN_WHITELIST`` will be
61 replaced with ``RTE_BUS_SCAN_EXCLUDED`` and ``RTE_BUS_SCAN_INCLUDED``
62 respectively. Likewise ``RTE_DEVTYPE_BLACKLISTED_PCI`` and
63 ``RTE_DEVTYPE_WHITELISTED_PCI`` will be replaced with
64 ``RTE_DEVTYPE_EXCLUDED`` and ``RTE_DEVTYPE_INCLUDED``.
66 The old macros will be marked as deprecated in 20.11 and any
67 usage will cause a compile warning. They will be removed in
70 The command line arguments to ``rte_eal_init`` will change from
71 ``-b, --pci-blacklist`` to ``-x, --exclude`` and
72 ``-w, --pci-whitelist`` to ``-i, --include``.
73 The old command line arguments will continue to be accepted in 20.11
74 but will cause a runtime warning message. The old arguments will
75 be removed in a future release.
77 * eal: The function ``rte_eal_remote_launch`` will return new error codes
78 after read or write error on the pipe, instead of calling ``rte_panic``.
80 * eal: The ``rte_logs`` struct and global symbol will be made private to
81 remove it from the externally visible ABI and allow it to be updated in the
84 * eal: The ``rte_dev_event`` structure will be made private to the EAL as no
85 public API makes use of it.
87 * rte_atomicNN_xxx: These APIs do not take memory order parameter. This does
88 not allow for writing optimized code for all the CPU architectures supported
89 in DPDK. DPDK will adopt C11 atomic operations semantics and provide wrappers
90 using C11 atomic built-ins. These wrappers must be used for patches that
91 need to be merged in 20.08 onwards. This change will not introduce any
92 performance degradation.
94 * rte_smp_*mb: These APIs provide full barrier functionality. However, many
95 use cases do not require full barriers. To support such use cases, DPDK will
96 adopt C11 barrier semantics and provide wrappers using C11 atomic built-ins.
97 These wrappers must be used for patches that need to be merged in 20.08
98 onwards. This change will not introduce any performance degradation.
100 * rte_cio_*mb: Since the IO barriers for ARMv8 platforms are relaxed from DSB
101 to DMB, rte_cio_*mb APIs provide the same functionality as rte_io_*mb
102 APIs (taking all platforms into consideration). rte_io_*mb APIs should be
103 used in the place of rte_cio_*mb APIs. The rte_cio_*mb APIs will be
104 deprecated in 20.11 release.
106 * igb_uio: In the view of reducing the kernel dependency from the main tree,
107 as a first step, the Technical Board decided to move ``igb_uio``
108 kernel module to the dpdk-kmods repository in the /linux/igb_uio/ directory
110 Minutes of Technical Board Meeting of `2019-11-06
111 <https://mails.dpdk.org/archives/dev/2019-November/151763.html>`_.
113 * lib: will fix extending some enum/define breaking the ABI. There are multiple
114 samples in DPDK that enum/define terminated with a ``.*MAX.*`` value which is
115 used by iterators, and arrays holding these values are sized with this
116 ``.*MAX.*`` value. So extending this enum/define increases the ``.*MAX.*``
117 value which increases the size of the array and depending on how/where the
118 array is used this may break the ABI.
119 ``RTE_ETH_FLOW_MAX`` is one sample of the mentioned case, adding a new flow
120 type will break the ABI because of ``flex_mask[RTE_ETH_FLOW_MAX]`` array
121 usage in following public struct hierarchy:
122 ``rte_eth_fdir_flex_conf -> rte_fdir_conf -> rte_eth_conf (in the middle)``.
123 Need to identify this kind of usages and fix in 20.11, otherwise this blocks
124 us extending existing enum/define.
125 One solution can be using a fixed size array instead of ``.*MAX.*`` value.
127 * pci: The PCI resources map API (``pci_map_resource`` and
128 ``pci_unmap_resource``) was not abstracting the Unix mmap flags (see the
129 workaround for Windows support implemented in the commit
130 9d2b24593724 ("pci: keep API compatibility with mmap values")).
131 This API will be removed from the public API in 20.11 and moved to the PCI
132 bus driver along with the PCI resources lists and associated structures
133 (``pci_map``, ``pci_msix_table``, ``mapped_pci_resource`` and
134 ``mapped_pci_res_list``).
135 With this removal, there won't be a need for the mentioned workaround which
138 * pci: The ``rte_kernel_driver`` enum defined in rte_dev.h will be made private
139 to the PCI subsystem as it is used only by the PCI bus driver and PCI
141 The associated field ``kdrv`` in the ethdev ``rte_eth_dev_data`` structure
142 will be removed as it gave no useful abstracted information to the
143 applications and had no user (neither internal nor external).
145 * mbuf: Some fields will be converted to dynamic API in DPDK 20.11
146 in order to reserve more space for the dynamic fields, as explained in
147 `this presentation <https://www.youtube.com/watch?v=Ttl6MlhmzWY>`_.
148 The following static fields will be moved as dynamic:
151 - ``userdata`` / ``udata64``
154 As a consequence, the layout of the ``struct rte_mbuf`` will be re-arranged,
155 avoiding impact on vectorized implementation of the driver datapaths,
156 while evaluating performance gains of a better use of the first cache line.
158 The deprecated unioned fields ``buf_physaddr`` and ``refcnt_atomic``
159 (as explained below) will be removed in DPDK 20.11.
161 * mbuf: ``refcnt_atomic`` member in structures ``rte_mbuf`` and
162 ``rte_mbuf_ext_shared_info`` is of type ``rte_atomic16_t``.
163 Due to adoption of C11 atomic builtins, the field ``refcnt_atomic``
164 will be replaced with ``refcnt`` of type ``uint16_t`` in DPDK 20.11.
166 * ethdev: Split the ``struct eth_dev_ops`` struct to hide it as much as possible
167 will be done in 20.11.
168 Currently the ``struct eth_dev_ops`` struct is accessible by the application
169 because some inline functions, like ``rte_eth_tx_descriptor_status()``,
170 access the struct directly.
171 The struct will be separate in two, the ops used by inline functions will be
172 moved next to Rx/Tx burst functions, rest of the ``struct eth_dev_ops`` struct
173 will be moved to header file for drivers to hide it from applications.
175 * ethdev: the legacy filter API, including
176 ``rte_eth_dev_filter_supported()``, ``rte_eth_dev_filter_ctrl()`` as well
177 as filter types MACVLAN, ETHERTYPE, FLEXIBLE, SYN, NTUPLE, TUNNEL, FDIR,
178 HASH and L2_TUNNEL, is superseded by the generic flow API (rte_flow) in
179 PMDs that implement the latter.
180 The legacy API will be removed in DPDK 20.11.
182 * ethdev: The flow director API, including ``rte_eth_conf.fdir_conf`` field,
183 and the related structures (``rte_fdir_*`` and ``rte_eth_fdir_*``),
184 will be removed in DPDK 20.11.
186 * ethdev: The legacy L2 tunnel filtering API is deprecated as the rest of
187 the legacy filtering API.
188 The functions ``rte_eth_dev_l2_tunnel_eth_type_conf`` and
189 ``rte_eth_dev_l2_tunnel_offload_set`` which were not marked as deprecated,
190 will be removed in DPDK 20.11.
192 * ethdev: Update API functions returning ``void`` to return ``int`` with
193 negative errno values to indicate various error conditions (e.g.
194 invalid port ID, unsupported operation, failed operation):
196 - ``rte_eth_dev_stop``
197 - ``rte_eth_dev_close``
199 * ethdev: The temporary flag RTE_ETH_DEV_CLOSE_REMOVE will be removed in 20.11.
200 As a consequence, the new behaviour introduced in 18.11 will be effective
201 for all drivers: generic port resources are freed on close operation.
202 Private resources are expected to be released in the ``dev_close`` callback.
203 More details in http://inbox.dpdk.org/dev/5248162.j6AOsuQRmx@thomas/
205 * ethdev: New offload flags ``DEV_RX_OFFLOAD_FLOW_MARK`` will be added in 19.11.
206 This will allow application to enable or disable PMDs from updating
207 ``rte_mbuf::hash::fdir``.
208 This scheme will allow PMDs to avoid writes to ``rte_mbuf`` fields on Rx and
209 thereby improve Rx performance if application wishes do so.
210 In 19.11 PMDs will still update the field even when the offload is not
213 * ethdev: Add new fields to ``rte_eth_rxconf`` to configure the receiving
214 queues to split ingress packets into multiple segments according to the
215 specified lengths into the buffers allocated from the specified
216 memory pools. The backward compatibility to existing API is preserved.
218 * ethdev: ``rx_descriptor_done`` dev_ops and ``rte_eth_rx_descriptor_done``
219 will be deprecated in 20.11 and will be removed in 21.11.
220 Existing ``rte_eth_rx_descriptor_status`` and ``rte_eth_tx_descriptor_status``
221 APIs can be used as replacement.
223 * ethdev: The port mirroring API can be replaced with a more fine grain flow API.
224 The structs ``rte_eth_mirror_conf``, ``rte_eth_vlan_mirror`` and the functions
225 ``rte_eth_mirror_rule_set``, ``rte_eth_mirror_rule_reset`` will be marked
226 as deprecated in DPDK 20.11, along with the associated macros ``ETH_MIRROR_*``.
227 This API will be fully removed in DPDK 21.11.
229 * ethdev: The ``struct rte_flow_item_eth`` and ``struct rte_flow_item_vlan``
230 structs will be modified, to include an additional value, indicating existence
231 or absence of a VLAN header following the current header, as proposed in RFC
232 https://mails.dpdk.org/archives/dev/2020-August/177536.html.
234 * ethdev: The ``struct rte_flow_item_ipv6`` struct will be modified to include
235 additional values, indicating existence or absence of IPv6 extension headers
236 following the IPv6 header, as proposed in RFC
237 https://mails.dpdk.org/archives/dev/2020-August/177257.html.
239 * ethdev: Some internal APIs for driver usage are exported in the .map file.
240 Now DPDK has ``__rte_internal`` marker so we can mark internal APIs and move
241 them to the INTERNAL block in .map. Although these APIs are internal it will
242 break the ABI checks, that is why change is planned for 20.11.
243 The list of internal APIs are mainly ones listed in ``rte_ethdev_driver.h``.
245 * traffic manager: All traffic manager API's in ``rte_tm.h`` were mistakenly made
246 ABI stable in the v19.11 release. The TM maintainer and other contributors have
247 agreed to keep the TM APIs as experimental in expectation of additional spec
248 improvements. Therefore, all APIs in ``rte_tm.h`` will be marked back as
249 experimental in v20.11 DPDK release. For more details, please see `the thread
250 <https://mails.dpdk.org/archives/dev/2020-April/164970.html>`_.
252 * pmd_dpaa: The API ``rte_pmd_dpaa_set_tx_loopback`` will have extended
253 ``port_id`` definition from ``uint8_t`` to ``uint16_t``.
255 * vhost: Vhost-user dequeue zero-copy support will be removed in 20.11.
256 The only known user is OVS where the feature is still experimental,
257 and has not received any update for 2.5 years.
258 This feature faces reliability issues and is often conflicting with
259 new features being implemented.
261 * security: The API ``rte_security_session_create`` takes only single mempool
262 for session and session private data. So the application need to create
263 mempool for twice the number of sessions needed and will also lead to
264 wastage of memory as session private data need more memory compared to session.
265 Hence the API will be modified to take two mempool pointers - one for session
266 and one for private data.
268 * cryptodev: ``RTE_CRYPTO_AEAD_LIST_END`` from ``enum rte_crypto_aead_algorithm``,
269 ``RTE_CRYPTO_CIPHER_LIST_END`` from ``enum rte_crypto_cipher_algorithm`` and
270 ``RTE_CRYPTO_AUTH_LIST_END`` from ``enum rte_crypto_auth_algorithm``
273 * cryptodev: support for using IV with all sizes is added, J0 still can
274 be used but only when IV length in following structs ``rte_crypto_auth_xform``,
275 ``rte_crypto_aead_xform`` is set to zero. When IV length is greater or equal
276 to one it means it represents IV, when is set to zero it means J0 is used
277 directly, in this case 16 bytes of J0 need to be passed.
279 * eventdev: Following structures will be modified to support DLB PMD
280 and future extensions:
282 - ``rte_event_dev_info``
283 - ``rte_event_dev_config``
284 - ``rte_event_port_conf``
286 Patches containing justification, documentation, and proposed modifications
289 - https://patches.dpdk.org/patch/71457/
290 - https://patches.dpdk.org/patch/71456/
292 * rawdev: The rawdev APIs which take a device-specific structure as
293 parameter directly, or indirectly via a "private" pointer inside another
294 structure, will be modified to take an additional parameter of the
295 structure size. The affected APIs will include ``rte_rawdev_info_get``,
296 ``rte_rawdev_configure``, ``rte_rawdev_queue_conf_get`` and
297 ``rte_rawdev_queue_setup``.
299 * acl: ``RTE_ACL_CLASSIFY_NUM`` enum value will be removed.
300 This enum value is not used inside DPDK, while it prevents to add new
301 classify algorithms without causing an ABI breakage.
303 * sched: To allow more traffic classes, flexible mapping of pipe queues to
304 traffic classes, and subport level configuration of pipes and queues
305 changes will be made to macros, data structures and API functions defined
306 in "rte_sched.h". These changes are aligned to improvements suggested in the
307 RFC https://mails.dpdk.org/archives/dev/2018-November/120035.html.
309 * metrics: The function ``rte_metrics_init`` will have a non-void return
310 in order to notify errors instead of calling ``rte_exit``.
312 * power: ``rte_power_set_env`` function will no longer return 0 on attempt
313 to set new power environment if power environment was already initialized.
314 In this case the function will return -1 unless the environment is unset first
315 (using ``rte_power_unset_env``). Other function usage scenarios will not change.
317 * python: Since the beginning of 2020, Python 2 has officially reached
318 end-of-support: https://www.python.org/doc/sunset-python-2/.
319 Python 2 support will be completely removed in 20.11.
320 In 20.08, explicit deprecation warnings will be displayed when running
321 scripts with Python 2.
323 * dpdk-setup.sh: This old script relies on deprecated stuff, and especially
324 ``make``. Given environments are too much variables for such a simple script,
325 it will be removed in DPDK 20.11.
326 Some useful parts may be converted into specific scripts.