1.. SPDX-License-Identifier: BSD-3-Clause 2 Copyright 2018 The DPDK contributors 3 4ABI and API Deprecation 5======================= 6 7See the guidelines document for details of the :doc:`ABI policy 8<../contributing/abi_policy>`. 9 10With DPDK 23.11, there will be a new major ABI version: 24. 11This means that during the development of 23.11, 12new items may be added to structs or enums, 13even if those additions involve an ABI compatibility breakage. 14 15Other API and ABI deprecation notices are to be posted below. 16 17Deprecation Notices 18------------------- 19 20* build: The ``enable_kmods`` option is deprecated and will be removed in a future release. 21 Setting/clearing the option has no impact on the build. 22 Instead, kernel modules will be always built for OS's where out-of-tree kernel modules 23 are required for DPDK operation. 24 Currently, this means that modules will only be built for FreeBSD. 25 No modules are shipped with DPDK for either Linux or Windows. 26 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. 29 30* telemetry: The functions ``rte_tel_data_add_array_u64`` and ``rte_tel_data_add_dict_u64``, 31 used by telemetry callbacks for adding unsigned integer values to be returned to the user, 32 are renamed to ``rte_tel_data_add_array_uint`` and ``rte_tel_data_add_dict_uint`` respectively. 33 As such, the old function names are deprecated and will be removed in a future release. 34 35* rte_atomicNN_xxx: These APIs do not take memory order parameter. This does 36 not allow for writing optimized code for all the CPU architectures supported 37 in DPDK. DPDK has adopted the atomic operations from 38 https://gcc.gnu.org/onlinedocs/gcc/_005f_005fatomic-Builtins.html. These 39 operations must be used for patches that need to be merged in 20.08 onwards. 40 This change will not introduce any performance degradation. 41 42* rte_smp_*mb: These APIs provide full barrier functionality. However, many 43 use cases do not require full barriers. To support such use cases, DPDK has 44 adopted atomic operations from 45 https://gcc.gnu.org/onlinedocs/gcc/_005f_005fatomic-Builtins.html. These 46 operations and a new wrapper ``rte_atomic_thread_fence`` instead of 47 ``__atomic_thread_fence`` must be used for patches that need to be merged in 48 20.08 onwards. This change will not introduce any performance degradation. 49 50* lib: will fix extending some enum/define breaking the ABI. There are multiple 51 samples in DPDK that enum/define terminated with a ``.*MAX.*`` value which is 52 used by iterators, and arrays holding these values are sized with this 53 ``.*MAX.*`` value. So extending this enum/define increases the ``.*MAX.*`` 54 value which increases the size of the array and depending on how/where the 55 array is used this may break the ABI. 56 ``RTE_ETH_FLOW_MAX`` is one sample of the mentioned case, adding a new flow 57 type will break the ABI because of ``flex_mask[RTE_ETH_FLOW_MAX]`` array 58 usage in following public struct hierarchy: 59 ``rte_eth_fdir_flex_conf -> rte_eth_fdir_conf -> rte_eth_conf (in the middle)``. 60 Need to identify this kind of usages and fix in 20.11, otherwise this blocks 61 us extending existing enum/define. 62 One solution can be using a fixed size array instead of ``.*MAX.*`` value. 63 64* net, ethdev: The flow item ``RTE_FLOW_ITEM_TYPE_VXLAN_GPE`` 65 is replaced with ``RTE_FLOW_ITEM_TYPE_VXLAN``. 66 The struct ``rte_flow_item_vxlan_gpe`` and its mask ``rte_flow_item_vxlan_gpe_mask`` 67 are replaced with ``rte_flow_item_vxlan`` and ``rte_flow_item_vxlan_mask``. 68 The flow item ``RTE_FLOW_ITEM_TYPE_VXLAN_GPE``, 69 the structs ``rte_flow_item_vxlan_gpe``, ``rte_flow_item_vxlan_gpe_mask``, 70 and the header struct ``rte_vxlan_gpe_hdr`` with the macro ``RTE_ETHER_VXLAN_GPE_HLEN`` 71 will be removed in DPDK 25.11. 72 73* ethdev: The flow API matching pattern structures, ``struct rte_flow_item_*``, 74 should start with relevant protocol header structure from lib/net/. 75 The individual protocol header fields and the protocol header struct 76 may be kept together in a union as a first migration step. 77 In future (target is DPDK 23.11), the protocol header fields will be cleaned 78 and only protocol header struct will remain. 79 80 These items are not compliant (not including struct from lib/net/): 81 82 - ``rte_flow_item_ah`` 83 - ``rte_flow_item_e_tag`` 84 - ``rte_flow_item_geneve`` 85 - ``rte_flow_item_geneve_opt`` 86 - ``rte_flow_item_gre`` 87 - ``rte_flow_item_icmp6`` 88 - ``rte_flow_item_icmp6_nd_na`` 89 - ``rte_flow_item_icmp6_nd_ns`` 90 - ``rte_flow_item_icmp6_nd_opt`` 91 - ``rte_flow_item_icmp6_nd_opt_sla_eth`` 92 - ``rte_flow_item_icmp6_nd_opt_tla_eth`` 93 - ``rte_flow_item_igmp`` 94 - ``rte_flow_item_ipv6_ext`` 95 - ``rte_flow_item_l2tpv3oip`` 96 - ``rte_flow_item_mpls`` 97 - ``rte_flow_item_nsh`` 98 - ``rte_flow_item_nvgre`` 99 - ``rte_flow_item_pfcp`` 100 - ``rte_flow_item_pppoe`` 101 - ``rte_flow_item_pppoe_proto_id`` 102 103* ethdev: Queue specific stats fields will be removed from ``struct rte_eth_stats``. 104 Mentioned fields are: ``q_ipackets``, ``q_opackets``, ``q_ibytes``, ``q_obytes``, 105 ``q_errors``. 106 Instead queue stats will be received via xstats API. Current method support 107 will be limited to maximum 256 queues. 108 Also compile time flag ``RTE_ETHDEV_QUEUE_STAT_CNTRS`` will be removed. 109 110* ethdev: Flow actions ``PF`` and ``VF`` have been deprecated since DPDK 21.11 111 and are yet to be removed. That still has not happened because there are net 112 drivers which support combined use of either action ``PF`` or action ``VF`` 113 with action ``QUEUE``, namely, i40e, ixgbe and txgbe (L2 tunnel rule). 114 It is unclear whether it is acceptable to just drop support for 115 such a complex use case, so maintainers of the said drivers 116 should take a closer look at this and provide assistance. 117 118* ethdev: Actions ``OF_DEC_NW_TTL``, ``SET_IPV4_SRC``, ``SET_IPV4_DST``, 119 ``SET_IPV6_SRC``, ``SET_IPV6_DST``, ``SET_TP_SRC``, ``SET_TP_DST``, 120 ``DEC_TTL``, ``SET_TTL``, ``SET_MAC_SRC``, ``SET_MAC_DST``, ``INC_TCP_SEQ``, 121 ``DEC_TCP_SEQ``, ``INC_TCP_ACK``, ``DEC_TCP_ACK``, ``SET_IPV4_DSCP``, 122 ``SET_IPV6_DSCP``, ``SET_TAG``, ``SET_META`` are marked as legacy and 123 superseded by the generic ``RTE_FLOW_ACTION_TYPE_MODIFY_FIELD``. 124 The legacy actions should be removed 125 once ``MODIFY_FIELD`` alternative is implemented in drivers. 126 127* pipeline: The pipeline library legacy API (functions rte_pipeline_*) 128 will be deprecated and subsequently removed in DPDK 24.11 release. 129 Before this, the new pipeline library API (functions rte_swx_pipeline_*) 130 will gradually transition from experimental to stable status. 131 132* table: The table library legacy API (functions rte_table_*) 133 will be deprecated and subsequently removed in DPDK 24.11 release. 134 Before this, the new table library API (functions rte_swx_table_*) 135 will gradually transition from experimental to stable status. 136 137* port: The port library legacy API (functions rte_port_*) 138 will be deprecated and subsequently removed in DPDK 24.11 release. 139 Before this, the new port library API (functions rte_swx_port_*) 140 will gradually transition from experimental to stable status. 141