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: The terms blacklist and whitelist to describe devices used
32 by DPDK will be replaced in the 20.11 relase.
33 This will apply to command line arguments as well as macros.
35 The macro ``RTE_DEV_BLACKLISTED`` will be replaced with ``RTE_DEV_EXCLUDED``
36 and ``RTE_DEV_WHITELISTED`` will be replaced with ``RTE_DEV_INCLUDED``
37 ``RTE_BUS_SCAN_BLACKLIST`` and ``RTE_BUS_SCAN_WHITELIST`` will be
38 replaced with ``RTE_BUS_SCAN_EXCLUDED`` and ``RTE_BUS_SCAN_INCLUDED``
39 respectively. Likewise ``RTE_DEVTYPE_BLACKLISTED_PCI`` and
40 ``RTE_DEVTYPE_WHITELISTED_PCI`` will be replaced with
41 ``RTE_DEVTYPE_EXCLUDED`` and ``RTE_DEVTYPE_INCLUDED``.
43 The old macros will be marked as deprecated in 20.11 and any
44 usage will cause a compile warning. They will be removed in
47 The command line arguments to ``rte_eal_init`` will change from
48 ``-b, --pci-blacklist`` to ``-x, --exclude`` and
49 ``-w, --pci-whitelist`` to ``-i, --include``.
50 The old command line arguments will continue to be accepted in 20.11
51 but will cause a runtime warning message. The old arguments will
52 be removed in a future release.
54 * eal: The function ``rte_eal_remote_launch`` will return new error codes
55 after read or write error on the pipe, instead of calling ``rte_panic``.
57 * rte_atomicNN_xxx: These APIs do not take memory order parameter. This does
58 not allow for writing optimized code for all the CPU architectures supported
59 in DPDK. DPDK will adopt C11 atomic operations semantics and provide wrappers
60 using C11 atomic built-ins. These wrappers must be used for patches that
61 need to be merged in 20.08 onwards. This change will not introduce any
62 performance degradation.
64 * rte_smp_*mb: These APIs provide full barrier functionality. However, many
65 use cases do not require full barriers. To support such use cases, DPDK will
66 adopt C11 barrier semantics and provide wrappers using C11 atomic built-ins.
67 These wrappers must be used for patches that need to be merged in 20.08
68 onwards. This change will not introduce any performance degradation.
70 * lib: will fix extending some enum/define breaking the ABI. There are multiple
71 samples in DPDK that enum/define terminated with a ``.*MAX.*`` value which is
72 used by iterators, and arrays holding these values are sized with this
73 ``.*MAX.*`` value. So extending this enum/define increases the ``.*MAX.*``
74 value which increases the size of the array and depending on how/where the
75 array is used this may break the ABI.
76 ``RTE_ETH_FLOW_MAX`` is one sample of the mentioned case, adding a new flow
77 type will break the ABI because of ``flex_mask[RTE_ETH_FLOW_MAX]`` array
78 usage in following public struct hierarchy:
79 ``rte_eth_fdir_flex_conf -> rte_fdir_conf -> rte_eth_conf (in the middle)``.
80 Need to identify this kind of usages and fix in 20.11, otherwise this blocks
81 us extending existing enum/define.
82 One solution can be using a fixed size array instead of ``.*MAX.*`` value.
84 * mbuf: Some fields will be converted to dynamic API in DPDK 20.11
85 in order to reserve more space for the dynamic fields, as explained in
86 `this presentation <https://www.youtube.com/watch?v=Ttl6MlhmzWY>`_.
87 As a consequence, the layout of the ``struct rte_mbuf`` will be re-arranged,
88 avoiding impact on vectorized implementation of the driver datapaths,
89 while evaluating performance gains of a better use of the first cache line.
92 * ethdev: the legacy filter API, including
93 ``rte_eth_dev_filter_supported()``, ``rte_eth_dev_filter_ctrl()`` as well
94 as filter types SYN, NTUPLE, TUNNEL, FDIR,
95 HASH and L2_TUNNEL, is superseded by the generic flow API (rte_flow) in
96 PMDs that implement the latter.
97 The legacy API will be removed in DPDK 20.11.
99 * ethdev: The flow director API, including ``rte_eth_conf.fdir_conf`` field,
100 and the related structures (``rte_fdir_*`` and ``rte_eth_fdir_*``),
101 will be removed in DPDK 20.11.
103 * ethdev: The legacy L2 tunnel filtering API is deprecated as the rest of
104 the legacy filtering API.
105 The functions ``rte_eth_dev_l2_tunnel_eth_type_conf`` and
106 ``rte_eth_dev_l2_tunnel_offload_set`` which were not marked as deprecated,
107 will be removed in DPDK 20.11.
109 * ethdev: New offload flags ``DEV_RX_OFFLOAD_FLOW_MARK`` will be added in 19.11.
110 This will allow application to enable or disable PMDs from updating
111 ``rte_mbuf::hash::fdir``.
112 This scheme will allow PMDs to avoid writes to ``rte_mbuf`` fields on Rx and
113 thereby improve Rx performance if application wishes do so.
114 In 19.11 PMDs will still update the field even when the offload is not
117 * ethdev: ``rx_descriptor_done`` dev_ops and ``rte_eth_rx_descriptor_done``
118 will be removed in 21.11.
119 Existing ``rte_eth_rx_descriptor_status`` and ``rte_eth_tx_descriptor_status``
120 APIs can be used as replacement.
122 * ethdev: The port mirroring API can be replaced with a more fine grain flow API.
123 The structs ``rte_eth_mirror_conf``, ``rte_eth_vlan_mirror`` and the functions
124 ``rte_eth_mirror_rule_set``, ``rte_eth_mirror_rule_reset`` will be marked
125 as deprecated in DPDK 20.11, along with the associated macros ``ETH_MIRROR_*``.
126 This API will be fully removed in DPDK 21.11.
128 * ethdev: Queue specific stats fields will be removed from ``struct rte_eth_stats``.
129 Mentioned fields are: ``q_ipackets``, ``q_opackets``, ``q_ibytes``, ``q_obytes``,
131 Instead queue stats will be received via xstats API. Current method support
132 will be limited to maximum 256 queues.
133 Also compile time flag ``RTE_ETHDEV_QUEUE_STAT_CNTRS`` will be removed.
135 * sched: To allow more traffic classes, flexible mapping of pipe queues to
136 traffic classes, and subport level configuration of pipes and queues
137 changes will be made to macros, data structures and API functions defined
138 in "rte_sched.h". These changes are aligned to improvements suggested in the
139 RFC https://mails.dpdk.org/archives/dev/2018-November/120035.html.
141 * metrics: The function ``rte_metrics_init`` will have a non-void return
142 in order to notify errors instead of calling ``rte_exit``.
144 * power: ``rte_power_set_env`` function will no longer return 0 on attempt
145 to set new power environment if power environment was already initialized.
146 In this case the function will return -1 unless the environment is unset first
147 (using ``rte_power_unset_env``). Other function usage scenarios will not change.
149 * cmdline: ``cmdline`` structure will be made opaque to hide platform-specific
150 content. On Linux and FreeBSD, supported prior to DPDK 20.11,
151 original structure will be kept until DPDK 21.11.
153 * dpdk-setup.sh: This old script relies on deprecated stuff, and especially
154 ``make``. Given environments are too much variables for such a simple script,
155 it will be removed in DPDK 20.11.
156 Some useful parts may be converted into specific scripts.