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 * build: The macros defined to indicate which DPDK libraries and drivers
15 are included in the meson build are changing to a standardized format of
16 ``RTE_LIB_<NAME>`` and ``RTE_<CLASS>_<NAME>``, where ``NAME`` is the
17 upper-case component name, e.g. EAL, ETHDEV, IXGBE, and ``CLASS`` is the
18 upper-case name of the device class to which a driver belongs e.g.
19 ``NET``, ``CRYPTO``, ``VDPA``. The old macros are deprecated and will be
20 removed in a future release.
22 * meson: The minimum supported version of meson for configuring and building
23 DPDK will be increased to v0.47.1 (from 0.41) from DPDK 19.05 onwards. For
24 those users with a version earlier than 0.47.1, an updated copy of meson
25 can be got using the ``pip3`` tool (or ``python3 -m pip``) for downloading
28 * kvargs: The function ``rte_kvargs_process`` will get a new parameter
29 for returning key match count. It will ease handling of no-match case.
31 * eal: To be more inclusive in choice of naming, the DPDK project
32 will replace uses of master/slave in the API's and command line arguments.
34 References to master/slave in relation to lcore will be renamed
35 to initial/worker. The function ``rte_get_master_lcore()``
36 will be renamed to ``rte_get_initial_lcore()``.
37 For the 20.11 release, both names will be present and the
38 old function will be marked with the deprecated tag.
39 The old function will be removed in a future version.
41 The iterator for worker lcores will also change:
42 ``RTE_LCORE_FOREACH_SLAVE`` will be replaced with
43 ``RTE_LCORE_FOREACH_WORKER``.
45 The ``master-lcore`` argument to testpmd will be replaced
46 with ``initial-lcore``. The old ``master-lcore`` argument
47 will produce a runtime notification in 20.11 release, and
48 be removed completely in a future release.
50 * eal: The terms blacklist and whitelist to describe devices used
51 by DPDK will be replaced in the 20.11 relase.
52 This will apply to command line arguments as well as macros.
54 The macro ``RTE_DEV_BLACKLISTED`` will be replaced with ``RTE_DEV_EXCLUDED``
55 and ``RTE_DEV_WHITELISTED`` will be replaced with ``RTE_DEV_INCLUDED``
56 ``RTE_BUS_SCAN_BLACKLIST`` and ``RTE_BUS_SCAN_WHITELIST`` will be
57 replaced with ``RTE_BUS_SCAN_EXCLUDED`` and ``RTE_BUS_SCAN_INCLUDED``
58 respectively. Likewise ``RTE_DEVTYPE_BLACKLISTED_PCI`` and
59 ``RTE_DEVTYPE_WHITELISTED_PCI`` will be replaced with
60 ``RTE_DEVTYPE_EXCLUDED`` and ``RTE_DEVTYPE_INCLUDED``.
62 The old macros will be marked as deprecated in 20.11 and any
63 usage will cause a compile warning. They will be removed in
66 The command line arguments to ``rte_eal_init`` will change from
67 ``-b, --pci-blacklist`` to ``-x, --exclude`` and
68 ``-w, --pci-whitelist`` to ``-i, --include``.
69 The old command line arguments will continue to be accepted in 20.11
70 but will cause a runtime warning message. The old arguments will
71 be removed in a future release.
73 * eal: The function ``rte_eal_remote_launch`` will return new error codes
74 after read or write error on the pipe, instead of calling ``rte_panic``.
76 * rte_atomicNN_xxx: These APIs do not take memory order parameter. This does
77 not allow for writing optimized code for all the CPU architectures supported
78 in DPDK. DPDK will adopt C11 atomic operations semantics and provide wrappers
79 using C11 atomic built-ins. These wrappers must be used for patches that
80 need to be merged in 20.08 onwards. This change will not introduce any
81 performance degradation.
83 * rte_smp_*mb: These APIs provide full barrier functionality. However, many
84 use cases do not require full barriers. To support such use cases, DPDK will
85 adopt C11 barrier semantics and provide wrappers using C11 atomic built-ins.
86 These wrappers must be used for patches that need to be merged in 20.08
87 onwards. This change will not introduce any performance degradation.
89 * lib: will fix extending some enum/define breaking the ABI. There are multiple
90 samples in DPDK that enum/define terminated with a ``.*MAX.*`` value which is
91 used by iterators, and arrays holding these values are sized with this
92 ``.*MAX.*`` value. So extending this enum/define increases the ``.*MAX.*``
93 value which increases the size of the array and depending on how/where the
94 array is used this may break the ABI.
95 ``RTE_ETH_FLOW_MAX`` is one sample of the mentioned case, adding a new flow
96 type will break the ABI because of ``flex_mask[RTE_ETH_FLOW_MAX]`` array
97 usage in following public struct hierarchy:
98 ``rte_eth_fdir_flex_conf -> rte_fdir_conf -> rte_eth_conf (in the middle)``.
99 Need to identify this kind of usages and fix in 20.11, otherwise this blocks
100 us extending existing enum/define.
101 One solution can be using a fixed size array instead of ``.*MAX.*`` value.
103 * mbuf: Some fields will be converted to dynamic API in DPDK 20.11
104 in order to reserve more space for the dynamic fields, as explained in
105 `this presentation <https://www.youtube.com/watch?v=Ttl6MlhmzWY>`_.
106 The following static fields will be moved as dynamic:
109 - ``userdata`` / ``udata64``
112 As a consequence, the layout of the ``struct rte_mbuf`` will be re-arranged,
113 avoiding impact on vectorized implementation of the driver datapaths,
114 while evaluating performance gains of a better use of the first cache line.
117 * ethdev: the legacy filter API, including
118 ``rte_eth_dev_filter_supported()``, ``rte_eth_dev_filter_ctrl()`` as well
119 as filter types MACVLAN, ETHERTYPE, FLEXIBLE, SYN, NTUPLE, TUNNEL, FDIR,
120 HASH and L2_TUNNEL, is superseded by the generic flow API (rte_flow) in
121 PMDs that implement the latter.
122 The legacy API will be removed in DPDK 20.11.
124 * ethdev: The flow director API, including ``rte_eth_conf.fdir_conf`` field,
125 and the related structures (``rte_fdir_*`` and ``rte_eth_fdir_*``),
126 will be removed in DPDK 20.11.
128 * ethdev: The legacy L2 tunnel filtering API is deprecated as the rest of
129 the legacy filtering API.
130 The functions ``rte_eth_dev_l2_tunnel_eth_type_conf`` and
131 ``rte_eth_dev_l2_tunnel_offload_set`` which were not marked as deprecated,
132 will be removed in DPDK 20.11.
134 * ethdev: New offload flags ``DEV_RX_OFFLOAD_FLOW_MARK`` will be added in 19.11.
135 This will allow application to enable or disable PMDs from updating
136 ``rte_mbuf::hash::fdir``.
137 This scheme will allow PMDs to avoid writes to ``rte_mbuf`` fields on Rx and
138 thereby improve Rx performance if application wishes do so.
139 In 19.11 PMDs will still update the field even when the offload is not
142 * ethdev: ``rx_descriptor_done`` dev_ops and ``rte_eth_rx_descriptor_done``
143 will be removed in 21.11.
144 Existing ``rte_eth_rx_descriptor_status`` and ``rte_eth_tx_descriptor_status``
145 APIs can be used as replacement.
147 * ethdev: The port mirroring API can be replaced with a more fine grain flow API.
148 The structs ``rte_eth_mirror_conf``, ``rte_eth_vlan_mirror`` and the functions
149 ``rte_eth_mirror_rule_set``, ``rte_eth_mirror_rule_reset`` will be marked
150 as deprecated in DPDK 20.11, along with the associated macros ``ETH_MIRROR_*``.
151 This API will be fully removed in DPDK 21.11.
153 * ethdev: Queue specific stats fields will be removed from ``struct rte_eth_stats``.
154 Mentioned fields are: ``q_ipackets``, ``q_opackets``, ``q_ibytes``, ``q_obytes``,
156 Instead queue stats will be received via xstats API. Current method support
157 will be limited to maximum 256 queues.
158 Also compile time flag ``RTE_ETHDEV_QUEUE_STAT_CNTRS`` will be removed.
160 * cryptodev: support for using IV with all sizes is added, J0 still can
161 be used but only when IV length in following structs ``rte_crypto_auth_xform``,
162 ``rte_crypto_aead_xform`` is set to zero. When IV length is greater or equal
163 to one it means it represents IV, when is set to zero it means J0 is used
164 directly, in this case 16 bytes of J0 need to be passed.
166 * sched: To allow more traffic classes, flexible mapping of pipe queues to
167 traffic classes, and subport level configuration of pipes and queues
168 changes will be made to macros, data structures and API functions defined
169 in "rte_sched.h". These changes are aligned to improvements suggested in the
170 RFC https://mails.dpdk.org/archives/dev/2018-November/120035.html.
172 * metrics: The function ``rte_metrics_init`` will have a non-void return
173 in order to notify errors instead of calling ``rte_exit``.
175 * power: ``rte_power_set_env`` function will no longer return 0 on attempt
176 to set new power environment if power environment was already initialized.
177 In this case the function will return -1 unless the environment is unset first
178 (using ``rte_power_unset_env``). Other function usage scenarios will not change.
180 * cmdline: ``cmdline`` structure will be made opaque to hide platform-specific
181 content. On Linux and FreeBSD, supported prior to DPDK 20.11,
182 original structure will be kept until DPDK 21.11.
184 * dpdk-setup.sh: This old script relies on deprecated stuff, and especially
185 ``make``. Given environments are too much variables for such a simple script,
186 it will be removed in DPDK 20.11.
187 Some useful parts may be converted into specific scripts.