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>`. API and ABI deprecation notices are to be posted 9here. 10 11Deprecation Notices 12------------------- 13 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 ``pip``, or ``pip3``, tool for downloading python 18 packages. 19 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. 22 23* eal: The function ``rte_eal_remote_launch`` will return new error codes 24 after read or write error on the pipe, instead of calling ``rte_panic``. 25 26* eal: The ``rte_logs`` struct and global symbol will be made private to 27 remove it from the externally visible ABI and allow it to be updated in the 28 future. 29 30* rte_atomicNN_xxx: These APIs do not take memory order parameter. This does 31 not allow for writing optimized code for all the CPU architectures supported 32 in DPDK. DPDK will adopt C11 atomic operations semantics and provide wrappers 33 using C11 atomic built-ins. These wrappers must be used for patches that 34 need to be merged in 20.08 onwards. This change will not introduce any 35 performance degradation. 36 37* rte_smp_*mb: These APIs provide full barrier functionality. However, many 38 use cases do not require full barriers. To support such use cases, DPDK will 39 adopt C11 barrier semantics and provide wrappers using C11 atomic built-ins. 40 These wrappers must be used for patches that need to be merged in 20.08 41 onwards. This change will not introduce any performance degradation. 42 43* rte_cio_*mb: Since the IO barriers for ARMv8 platforms are relaxed from DSB 44 to DMB, rte_cio_*mb APIs provide the same functionality as rte_io_*mb 45 APIs (taking all platforms into consideration). rte_io_*mb APIs should be 46 used in the place of rte_cio_*mb APIs. The rte_cio_*mb APIs will be 47 deprecated in 20.11 release. 48 49* igb_uio: In the view of reducing the kernel dependency from the main tree, 50 as a first step, the Technical Board decided to move ``igb_uio`` 51 kernel module to the dpdk-kmods repository in the /linux/igb_uio/ directory 52 in 20.11. 53 Minutes of Technical Board Meeting of `2019-11-06 54 <https://mails.dpdk.org/archives/dev/2019-November/151763.html>`_. 55 56* lib: will fix extending some enum/define breaking the ABI. There are multiple 57 samples in DPDK that enum/define terminated with a ``.*MAX.*`` value which is 58 used by iterators, and arrays holding these values are sized with this 59 ``.*MAX.*`` value. So extending this enum/define increases the ``.*MAX.*`` 60 value which increases the size of the array and depending on how/where the 61 array is used this may break the ABI. 62 ``RTE_ETH_FLOW_MAX`` is one sample of the mentioned case, adding a new flow 63 type will break the ABI because of ``flex_mask[RTE_ETH_FLOW_MAX]`` array 64 usage in following public struct hierarchy: 65 ``rte_eth_fdir_flex_conf -> rte_fdir_conf -> rte_eth_conf (in the middle)``. 66 Need to identify this kind of usages and fix in 20.11, otherwise this blocks 67 us extending existing enum/define. 68 One solution can be using a fixed size array instead of ``.*MAX.*`` value. 69 70* ethdev: Split the ``struct eth_dev_ops`` struct to hide it as much as possible 71 will be done in 20.11. 72 Currently the ``struct eth_dev_ops`` struct is accessible by the application 73 because some inline functions, like ``rte_eth_tx_descriptor_status()``, 74 access the struct directly. 75 The struct will be separate in two, the ops used by inline functions will be 76 moved next to Rx/Tx burst functions, rest of the ``struct eth_dev_ops`` struct 77 will be moved to header file for drivers to hide it from applications. 78 79* ethdev: the legacy filter API, including 80 ``rte_eth_dev_filter_supported()``, ``rte_eth_dev_filter_ctrl()`` as well 81 as filter types MACVLAN, ETHERTYPE, FLEXIBLE, SYN, NTUPLE, TUNNEL, FDIR, 82 HASH and L2_TUNNEL, is superseded by the generic flow API (rte_flow) in 83 PMDs that implement the latter. 84 Target release for removal of the legacy API will be defined once most 85 PMDs have switched to rte_flow. 86 87* ethdev: Update API functions returning ``void`` to return ``int`` with 88 negative errno values to indicate various error conditions (e.g. 89 invalid port ID, unsupported operation, failed operation): 90 91 - ``rte_eth_dev_stop`` 92 - ``rte_eth_dev_close`` 93 94* ethdev: New offload flags ``DEV_RX_OFFLOAD_FLOW_MARK`` will be added in 19.11. 95 This will allow application to enable or disable PMDs from updating 96 ``rte_mbuf::hash::fdir``. 97 This scheme will allow PMDs to avoid writes to ``rte_mbuf`` fields on Rx and 98 thereby improve Rx performance if application wishes do so. 99 In 19.11 PMDs will still update the field even when the offload is not 100 enabled. 101 102* ethdev: ``rx_descriptor_done`` dev_ops and ``rte_eth_rx_descriptor_done`` 103 will be deprecated in 20.11 and will be removed in 21.11. 104 Existing ``rte_eth_rx_descriptor_status`` and ``rte_eth_tx_descriptor_status`` 105 APIs can be used as replacement. 106 107* ethdev: Some internal APIs for driver usage are exported in the .map file. 108 Now DPDK has ``__rte_internal`` marker so we can mark internal APIs and move 109 them to the INTERNAL block in .map. Although these APIs are internal it will 110 break the ABI checks, that is why change is planned for 20.11. 111 The list of internal APIs are mainly ones listed in ``rte_ethdev_driver.h``. 112 113* traffic manager: All traffic manager API's in ``rte_tm.h`` were mistakenly made 114 ABI stable in the v19.11 release. The TM maintainer and other contributors have 115 agreed to keep the TM APIs as experimental in expectation of additional spec 116 improvements. Therefore, all APIs in ``rte_tm.h`` will be marked back as 117 experimental in v20.11 DPDK release. For more details, please see `the thread 118 <https://mails.dpdk.org/archives/dev/2020-April/164970.html>`_. 119 120* cryptodev: support for using IV with all sizes is added, J0 still can 121 be used but only when IV length in following structs ``rte_crypto_auth_xform``, 122 ``rte_crypto_aead_xform`` is set to zero. When IV length is greater or equal 123 to one it means it represents IV, when is set to zero it means J0 is used 124 directly, in this case 16 bytes of J0 need to be passed. 125 126* sched: To allow more traffic classes, flexible mapping of pipe queues to 127 traffic classes, and subport level configuration of pipes and queues 128 changes will be made to macros, data structures and API functions defined 129 in "rte_sched.h". These changes are aligned to improvements suggested in the 130 RFC https://mails.dpdk.org/archives/dev/2018-November/120035.html. 131 132* metrics: The function ``rte_metrics_init`` will have a non-void return 133 in order to notify errors instead of calling ``rte_exit``. 134 135* power: ``rte_power_set_env`` function will no longer return 0 on attempt 136 to set new power environment if power environment was already initialized. 137 In this case the function will return -1 unless the environment is unset first 138 (using ``rte_power_unset_env``). Other function usage scenarios will not change. 139 140* python: Since the beginning of 2020, Python 2 has officially reached 141 end-of-support: https://www.python.org/doc/sunset-python-2/. 142 Python 2 support will be completely removed in 20.11. 143 In 20.08, explicit deprecation warnings will be displayed when running 144 scripts with Python 2. 145