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 * meson: The minimum supported version of meson for configuring and building
15 DPDK will be increased to v0.47.1 (from 0.41) from DPDK 19.05 onwards. For
16 those users with a version earlier than 0.47.1, an updated copy of meson
17 can be got using the ``pip3`` tool (or ``python3 -m pip``) for downloading
20 * kvargs: The function ``rte_kvargs_process`` will get a new parameter
21 for returning key match count. It will ease handling of no-match case.
23 * eal: To be more inclusive in choice of naming, the DPDK project
24 will replace uses of master/slave in the API's and command line arguments.
26 References to master/slave in relation to lcore will be renamed
27 to initial/worker. The function ``rte_get_master_lcore()``
28 will be renamed to ``rte_get_initial_lcore()``.
29 For the 20.11 release, both names will be present and the
30 old function will be marked with the deprecated tag.
31 The old function will be removed in a future version.
33 The iterator for worker lcores will also change:
34 ``RTE_LCORE_FOREACH_SLAVE`` will be replaced with
35 ``RTE_LCORE_FOREACH_WORKER``.
37 The ``master-lcore`` argument to testpmd will be replaced
38 with ``initial-lcore``. The old ``master-lcore`` argument
39 will produce a runtime notification in 20.11 release, and
40 be removed completely in a future release.
42 * eal: The terms blacklist and whitelist to describe devices used
43 by DPDK will be replaced in the 20.11 relase.
44 This will apply to command line arguments as well as macros.
46 The macro ``RTE_DEV_BLACKLISTED`` will be replaced with ``RTE_DEV_EXCLUDED``
47 and ``RTE_DEV_WHITELISTED`` will be replaced with ``RTE_DEV_INCLUDED``
48 ``RTE_BUS_SCAN_BLACKLIST`` and ``RTE_BUS_SCAN_WHITELIST`` will be
49 replaced with ``RTE_BUS_SCAN_EXCLUDED`` and ``RTE_BUS_SCAN_INCLUDED``
50 respectively. Likewise ``RTE_DEVTYPE_BLACKLISTED_PCI`` and
51 ``RTE_DEVTYPE_WHITELISTED_PCI`` will be replaced with
52 ``RTE_DEVTYPE_EXCLUDED`` and ``RTE_DEVTYPE_INCLUDED``.
54 The old macros will be marked as deprecated in 20.11 and any
55 usage will cause a compile warning. They will be removed in
58 The command line arguments to ``rte_eal_init`` will change from
59 ``-b, --pci-blacklist`` to ``-x, --exclude`` and
60 ``-w, --pci-whitelist`` to ``-i, --include``.
61 The old command line arguments will continue to be accepted in 20.11
62 but will cause a runtime warning message. The old arguments will
63 be removed in a future release.
65 * eal: The function ``rte_eal_remote_launch`` will return new error codes
66 after read or write error on the pipe, instead of calling ``rte_panic``.
68 * rte_atomicNN_xxx: These APIs do not take memory order parameter. This does
69 not allow for writing optimized code for all the CPU architectures supported
70 in DPDK. DPDK will adopt C11 atomic operations semantics and provide wrappers
71 using C11 atomic built-ins. These wrappers must be used for patches that
72 need to be merged in 20.08 onwards. This change will not introduce any
73 performance degradation.
75 * rte_smp_*mb: These APIs provide full barrier functionality. However, many
76 use cases do not require full barriers. To support such use cases, DPDK will
77 adopt C11 barrier semantics and provide wrappers using C11 atomic built-ins.
78 These wrappers must be used for patches that need to be merged in 20.08
79 onwards. This change will not introduce any performance degradation.
81 * lib: will fix extending some enum/define breaking the ABI. There are multiple
82 samples in DPDK that enum/define terminated with a ``.*MAX.*`` value which is
83 used by iterators, and arrays holding these values are sized with this
84 ``.*MAX.*`` value. So extending this enum/define increases the ``.*MAX.*``
85 value which increases the size of the array and depending on how/where the
86 array is used this may break the ABI.
87 ``RTE_ETH_FLOW_MAX`` is one sample of the mentioned case, adding a new flow
88 type will break the ABI because of ``flex_mask[RTE_ETH_FLOW_MAX]`` array
89 usage in following public struct hierarchy:
90 ``rte_eth_fdir_flex_conf -> rte_fdir_conf -> rte_eth_conf (in the middle)``.
91 Need to identify this kind of usages and fix in 20.11, otherwise this blocks
92 us extending existing enum/define.
93 One solution can be using a fixed size array instead of ``.*MAX.*`` value.
95 * mbuf: Some fields will be converted to dynamic API in DPDK 20.11
96 in order to reserve more space for the dynamic fields, as explained in
97 `this presentation <https://www.youtube.com/watch?v=Ttl6MlhmzWY>`_.
98 The following static fields will be moved as dynamic:
101 - ``userdata`` / ``udata64``
104 As a consequence, the layout of the ``struct rte_mbuf`` will be re-arranged,
105 avoiding impact on vectorized implementation of the driver datapaths,
106 while evaluating performance gains of a better use of the first cache line.
109 * ethdev: the legacy filter API, including
110 ``rte_eth_dev_filter_supported()``, ``rte_eth_dev_filter_ctrl()`` as well
111 as filter types MACVLAN, ETHERTYPE, FLEXIBLE, SYN, NTUPLE, TUNNEL, FDIR,
112 HASH and L2_TUNNEL, is superseded by the generic flow API (rte_flow) in
113 PMDs that implement the latter.
114 The legacy API will be removed in DPDK 20.11.
116 * ethdev: The flow director API, including ``rte_eth_conf.fdir_conf`` field,
117 and the related structures (``rte_fdir_*`` and ``rte_eth_fdir_*``),
118 will be removed in DPDK 20.11.
120 * ethdev: The legacy L2 tunnel filtering API is deprecated as the rest of
121 the legacy filtering API.
122 The functions ``rte_eth_dev_l2_tunnel_eth_type_conf`` and
123 ``rte_eth_dev_l2_tunnel_offload_set`` which were not marked as deprecated,
124 will be removed in DPDK 20.11.
126 * ethdev: Update API functions returning ``void`` to return ``int`` with
127 negative errno values to indicate various error conditions (e.g.
128 invalid port ID, unsupported operation, failed operation):
130 - ``rte_eth_dev_stop``
131 - ``rte_eth_dev_close``
133 * ethdev: New offload flags ``DEV_RX_OFFLOAD_FLOW_MARK`` will be added in 19.11.
134 This will allow application to enable or disable PMDs from updating
135 ``rte_mbuf::hash::fdir``.
136 This scheme will allow PMDs to avoid writes to ``rte_mbuf`` fields on Rx and
137 thereby improve Rx performance if application wishes do so.
138 In 19.11 PMDs will still update the field even when the offload is not
141 * ethdev: Add new fields to ``rte_eth_rxconf`` to configure the receiving
142 queues to split ingress packets into multiple segments according to the
143 specified lengths into the buffers allocated from the specified
144 memory pools. The backward compatibility to existing API is preserved.
146 * ethdev: ``rx_descriptor_done`` dev_ops and ``rte_eth_rx_descriptor_done``
147 will be removed in 21.11.
148 Existing ``rte_eth_rx_descriptor_status`` and ``rte_eth_tx_descriptor_status``
149 APIs can be used as replacement.
151 * ethdev: The port mirroring API can be replaced with a more fine grain flow API.
152 The structs ``rte_eth_mirror_conf``, ``rte_eth_vlan_mirror`` and the functions
153 ``rte_eth_mirror_rule_set``, ``rte_eth_mirror_rule_reset`` will be marked
154 as deprecated in DPDK 20.11, along with the associated macros ``ETH_MIRROR_*``.
155 This API will be fully removed in DPDK 21.11.
157 * ethdev: The ``struct rte_flow_item_eth`` and ``struct rte_flow_item_vlan``
158 structs will be modified, to include an additional value, indicating existence
159 or absence of a VLAN header following the current header, as proposed in RFC
160 https://mails.dpdk.org/archives/dev/2020-August/177536.html.
162 * security: The API ``rte_security_session_create`` takes only single mempool
163 for session and session private data. So the application need to create
164 mempool for twice the number of sessions needed and will also lead to
165 wastage of memory as session private data need more memory compared to session.
166 Hence the API will be modified to take two mempool pointers - one for session
167 and one for private data.
169 * cryptodev: support for using IV with all sizes is added, J0 still can
170 be used but only when IV length in following structs ``rte_crypto_auth_xform``,
171 ``rte_crypto_aead_xform`` is set to zero. When IV length is greater or equal
172 to one it means it represents IV, when is set to zero it means J0 is used
173 directly, in this case 16 bytes of J0 need to be passed.
175 * sched: To allow more traffic classes, flexible mapping of pipe queues to
176 traffic classes, and subport level configuration of pipes and queues
177 changes will be made to macros, data structures and API functions defined
178 in "rte_sched.h". These changes are aligned to improvements suggested in the
179 RFC https://mails.dpdk.org/archives/dev/2018-November/120035.html.
181 * metrics: The function ``rte_metrics_init`` will have a non-void return
182 in order to notify errors instead of calling ``rte_exit``.
184 * power: ``rte_power_set_env`` function will no longer return 0 on attempt
185 to set new power environment if power environment was already initialized.
186 In this case the function will return -1 unless the environment is unset first
187 (using ``rte_power_unset_env``). Other function usage scenarios will not change.
189 * cmdline: ``cmdline`` structure will be made opaque to hide platform-specific
190 content. On Linux and FreeBSD, supported prior to DPDK 20.11,
191 original structure will be kept until DPDK 21.11.
193 * dpdk-setup.sh: This old script relies on deprecated stuff, and especially
194 ``make``. Given environments are too much variables for such a simple script,
195 it will be removed in DPDK 20.11.
196 Some useful parts may be converted into specific scripts.