xref: /dpdk/doc/guides/rel_notes/deprecation.rst (revision c9902a15bd005b6d4fe072cf7b60fe4ee679155f)
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* kvargs: The function ``rte_kvargs_process`` will get a new parameter
15  for returning key match count. It will ease handling of no-match case.
16
17* eal: The function ``rte_eal_remote_launch`` will return new error codes
18  after read or write error on the pipe, instead of calling ``rte_panic``.
19
20* eal: The lcore state ``FINISHED`` will be removed from
21  the ``enum rte_lcore_state_t``.
22  The lcore state ``WAIT`` is enough to represent the same state.
23
24* eal: Making ``struct rte_intr_handle`` internal to avoid any ABI breakages
25  in future.
26
27* rte_atomicNN_xxx: These APIs do not take memory order parameter. This does
28  not allow for writing optimized code for all the CPU architectures supported
29  in DPDK. DPDK has adopted the atomic operations from
30  https://gcc.gnu.org/onlinedocs/gcc/_005f_005fatomic-Builtins.html. These
31  operations must be used for patches that need to be merged in 20.08 onwards.
32  This change will not introduce any performance degradation.
33
34* rte_smp_*mb: These APIs provide full barrier functionality. However, many
35  use cases do not require full barriers. To support such use cases, DPDK has
36  adopted atomic operations from
37  https://gcc.gnu.org/onlinedocs/gcc/_005f_005fatomic-Builtins.html. These
38  operations and a new wrapper ``rte_atomic_thread_fence`` instead of
39  ``__atomic_thread_fence`` must be used for patches that need to be merged in
40  20.08 onwards. This change will not introduce any performance degradation.
41
42* mbuf: The mbuf offload flags ``PKT_*`` will be renamed as ``RTE_MBUF_F_*``.
43  A compatibility layer will be kept until DPDK 22.11, except for the flags
44  that are already deprecated (``PKT_RX_L4_CKSUM_BAD``, ``PKT_RX_IP_CKSUM_BAD``,
45  ``PKT_RX_EIP_CKSUM_BAD``, ``PKT_TX_QINQ_PKT``) which will be removed.
46
47* pci: To reduce unnecessary ABIs exposed by DPDK bus driver, "rte_bus_pci.h"
48  will be made internal in 21.11 and macros/data structures/functions defined
49  in the header will not be considered as ABI anymore. This change is inspired
50  by the RFC https://patchwork.dpdk.org/project/dpdk/list/?series=17176.
51
52* lib: will fix extending some enum/define breaking the ABI. There are multiple
53  samples in DPDK that enum/define terminated with a ``.*MAX.*`` value which is
54  used by iterators, and arrays holding these values are sized with this
55  ``.*MAX.*`` value. So extending this enum/define increases the ``.*MAX.*``
56  value which increases the size of the array and depending on how/where the
57  array is used this may break the ABI.
58  ``RTE_ETH_FLOW_MAX`` is one sample of the mentioned case, adding a new flow
59  type will break the ABI because of ``flex_mask[RTE_ETH_FLOW_MAX]`` array
60  usage in following public struct hierarchy:
61  ``rte_eth_fdir_flex_conf -> rte_fdir_conf -> rte_eth_conf (in the middle)``.
62  Need to identify this kind of usages and fix in 20.11, otherwise this blocks
63  us extending existing enum/define.
64  One solution can be using a fixed size array instead of ``.*MAX.*`` value.
65
66* ethdev: Will add ``RTE_ETH_`` prefix to all ethdev macros/enums in v21.11.
67  Macros will be added for backward compatibility.
68  Backward compatibility macros will be removed on v22.11.
69  A few old backward compatibility macros from 2013 that does not have
70  proper prefix will be removed on v21.11.
71
72* ethdev: The flow director API, including ``rte_eth_conf.fdir_conf`` field,
73  and the related structures (``rte_fdir_*`` and ``rte_eth_fdir_*``),
74  will be removed in DPDK 20.11.
75
76* ethdev: New offload flags ``DEV_RX_OFFLOAD_FLOW_MARK`` will be added in 19.11.
77  This will allow application to enable or disable PMDs from updating
78  ``rte_mbuf::hash::fdir``.
79  This scheme will allow PMDs to avoid writes to ``rte_mbuf`` fields on Rx and
80  thereby improve Rx performance if application wishes do so.
81  In 19.11 PMDs will still update the field even when the offload is not
82  enabled.
83
84* ethdev: ``uint32_t max_rx_pkt_len`` field of ``struct rte_eth_rxmode``, will be
85  replaced by a new ``uint32_t mtu`` field of ``struct rte_eth_conf`` in v21.11.
86  The new ``mtu`` field will be used to configure the initial device MTU via
87  ``rte_eth_dev_configure()`` API.
88  Later MTU can be changed by ``rte_eth_dev_set_mtu()`` API as done now.
89  The existing ``(struct rte_eth_dev)->data->mtu`` variable will be used to store
90  the configured ``mtu`` value,
91  and this new ``(struct rte_eth_dev)->data->dev_conf.mtu`` variable will
92  be used to store the user configuration request.
93  Unlike ``max_rx_pkt_len``, which was valid only when ``JUMBO_FRAME`` enabled,
94  ``mtu`` field will be always valid.
95  When ``mtu`` config is not provided by the application, default ``RTE_ETHER_MTU``
96  value will be used.
97  ``(struct rte_eth_dev)->data->mtu`` should be updated after MTU set successfully,
98  either by ``rte_eth_dev_configure()`` or ``rte_eth_dev_set_mtu()``.
99
100  An application may need to configure device for a specific Rx packet size, like for
101  cases ``DEV_RX_OFFLOAD_SCATTER`` is not supported and device received packet size
102  can't be bigger than Rx buffer size.
103  To cover these cases an application needs to know the device packet overhead to be
104  able to calculate the ``mtu`` corresponding to a Rx buffer size, for this
105  ``(struct rte_eth_dev_info).max_rx_pktlen`` will be kept,
106  the device packet overhead can be calculated as:
107  ``(struct rte_eth_dev_info).max_rx_pktlen - (struct rte_eth_dev_info).max_mtu``
108
109* ethdev: ``rx_descriptor_done`` dev_ops and ``rte_eth_rx_descriptor_done``
110  will be removed in 21.11.
111  Existing ``rte_eth_rx_descriptor_status`` and ``rte_eth_tx_descriptor_status``
112  APIs can be used as replacement.
113
114* ethdev: The port mirroring API can be replaced with a more fine grain flow API.
115  The structs ``rte_eth_mirror_conf``, ``rte_eth_vlan_mirror`` and the functions
116  ``rte_eth_mirror_rule_set``, ``rte_eth_mirror_rule_reset`` will be marked
117  as deprecated in DPDK 20.11, along with the associated macros ``ETH_MIRROR_*``.
118  This API will be fully removed in DPDK 21.11.
119
120* ethdev: Announce moving from dedicated modify function for each field,
121  to using the general ``rte_flow_modify_field`` action.
122
123* ethdev: The struct ``rte_flow_action_modify_data`` will be modified
124  to support modifying fields larger than 64 bits.
125  In addition, documentation will be updated to clarify byte order.
126
127* ethdev: Attribute ``shared`` of the ``struct rte_flow_action_count``
128  is deprecated and will be removed in DPDK 21.11. Shared counters should
129  be managed using shared actions API (``rte_flow_shared_action_create`` etc).
130
131* ethdev: Definition of the flow API action ``RTE_FLOW_ACTION_TYPE_PORT_ID``
132  is ambiguous and needs clarification.
133  Structure ``rte_flow_action_port_id`` will be extended to specify
134  traffic direction to the represented entity or ethdev port itself
135  in DPDK 21.11.
136
137* ethdev: Flow API documentation is unclear if ethdev port used to create
138  a flow rule adds any implicit match criteria in the case of transfer rules.
139  The semantics will be clarified in DPDK 21.11 and it will require fixes in
140  drivers and applications which interpret it in a different way.
141
142* ethdev: The flow API matching pattern structures, ``struct rte_flow_item_*``,
143  should start with relevant protocol header.
144  Some matching pattern structures implements this by duplicating protocol header
145  fields in the struct. To clarify the intention and to be sure protocol header
146  is intact, will replace those fields with relevant protocol header struct.
147  In v21.02 both individual protocol header fields and the protocol header struct
148  will be added as union, target is switch usage to the protocol header by time.
149  In v21.11 LTS, protocol header fields will be cleaned and only protocol header
150  struct will remain.
151
152* ethdev: Add new Rx queue offload flag ``RTE_ETH_RX_OFFLOAD_SHARED_RXQ`` and
153  ``shared_group`` field to ``struct rte_eth_rxconf``.
154
155* ethdev: Queue specific stats fields will be removed from ``struct rte_eth_stats``.
156  Mentioned fields are: ``q_ipackets``, ``q_opackets``, ``q_ibytes``, ``q_obytes``,
157  ``q_errors``.
158  Instead queue stats will be received via xstats API. Current method support
159  will be limited to maximum 256 queues.
160  Also compile time flag ``RTE_ETHDEV_QUEUE_STAT_CNTRS`` will be removed.
161
162* ethdev: The offload flag ``PKT_RX_EIP_CKSUM_BAD`` will be removed and
163  replaced by the new flag ``PKT_RX_OUTER_IP_CKSUM_BAD``. The new name is more
164  consistent with existing outer header checksum status flag naming, which
165  should help in reducing confusion about its usage.
166
167* i40e: As there are both i40evf and iavf pmd, the functions of them are
168  duplicated. And now more and more advanced features are developed on iavf.
169  To keep consistent with kernel driver's name
170  (https://patchwork.ozlabs.org/patch/970154/), i40evf is no need to maintain.
171  Starting from 21.05, the default VF driver of i40e will be iavf, but i40evf
172  can still be used if users specify the devarg "driver=i40evf". I40evf will
173  be deleted in DPDK 21.11.
174
175* net: ``s_addr`` and ``d_addr`` fields of ``rte_ether_hdr`` structure
176  will be renamed in DPDK 21.11 to avoid conflict with Windows Sockets headers.
177
178* net: The structure ``rte_ipv4_hdr`` will have two unions.
179  The first union is for existing ``version_ihl`` byte
180  and new bitfield for version and IHL.
181  The second union is for existing ``fragment_offset``
182  and new bitfield for fragment flags and offset.
183
184* vhost: ``rte_vdpa_register_device``, ``rte_vdpa_unregister_device``,
185  ``rte_vhost_host_notifier_ctrl`` and ``rte_vdpa_relay_vring_used`` vDPA
186  driver interface will be marked as internal in DPDK v21.11.
187
188* vhost: rename ``struct vhost_device_ops`` to ``struct rte_vhost_device_ops``
189  in DPDK v21.11.
190
191* vhost: The experimental tags of ``rte_vhost_driver_get_protocol_features``,
192  ``rte_vhost_driver_get_queue_num``, ``rte_vhost_crypto_create``,
193  ``rte_vhost_crypto_free``, ``rte_vhost_crypto_fetch_requests``,
194  ``rte_vhost_crypto_finalize_requests``, ``rte_vhost_crypto_set_zero_copy``,
195  ``rte_vhost_va_from_guest_pa``, ``rte_vhost_extern_callback_register``,
196  and ``rte_vhost_driver_set_protocol_features`` functions will be removed
197  and the API functions will be made stable in DPDK 21.11.
198
199* compressdev: ``min`` and ``max`` fields of ``rte_param_log2_range`` structure
200  will be renamed in DPDK 21.11 to avoid conflict with Windows Sockets headers.
201
202* cryptodev: ``min`` and ``max`` fields of ``rte_crypto_param_range`` structure
203  will be renamed in DPDK 21.11 to avoid conflict with Windows Sockets headers.
204
205* cryptodev: The field ``dataunit_len`` of the ``struct rte_crypto_cipher_xform``
206  has a limited size ``uint16_t``.
207  It will be moved and extended as ``uint32_t`` in DPDK 21.11.
208
209* cryptodev: The structure ``rte_crypto_sym_vec`` would be updated to add
210  ``dest_sgl`` to support out of place processing.
211  This field will be null for inplace processing.
212  This change is targeted for DPDK 21.11.
213
214* cryptodev: The structure ``rte_crypto_vec`` would be updated to add
215  ``tot_len`` to support total buffer length.
216  This is required for security cases like IPsec and PDCP encryption offload
217  to know how much additional memory space is available in buffer other than
218  data length so that driver/HW can write expanded size data after encryption.
219  This change is targeted for DPDK 21.11.
220
221* cryptodev: Hide structures ``rte_cryptodev_sym_session`` and
222  ``rte_cryptodev_asym_session`` to remove unnecessary indirection between
223  session and the private data of session. An opaque pointer can be exposed
224  directly to application which can be attached to the ``rte_crypto_op``.
225
226* security: Hide structure ``rte_security_session`` and expose an opaque
227  pointer for the private data to the application which can be attached
228  to the packet while enqueuing.
229
230* security: The IPsec configuration structure
231  ``struct rte_security_ipsec_xform`` will be updated with new members to allow
232  SA lifetime configuration. A new structure would be introduced to replace the
233  current member, ``esn_soft_limit``.
234
235* security: The structure ``rte_security_ipsec_xform`` will be extended with
236  multiple fields: source and destination port of UDP encapsulation,
237  IPsec payload MSS (Maximum Segment Size), and ESN (Extended Sequence Number).
238
239* security: The IPsec SA config options ``struct rte_security_ipsec_sa_options``
240  will be updated with new fields to support new features like IPsec inner
241  checksum, tunnel header verification, TSO in case of protocol offload.
242
243* ipsec: The structure ``rte_ipsec_sa_prm`` will be extended with a new field
244  ``hdr_l3_len`` to configure tunnel L3 header length.
245
246* eventdev: The file ``rte_eventdev_pmd.h`` will be renamed to ``eventdev_driver.h``
247  to make the driver interface as internal and the structures ``rte_eventdev_data``,
248  ``rte_eventdev`` and ``rte_eventdevs`` will be moved to a new file named
249  ``rte_eventdev_core.h`` in DPDK 21.11.
250  The ``rte_`` prefix for internal structures and functions will be removed across the
251  library.
252  The experimental eventdev trace APIs and ``rte_event_vector_pool_create``,
253  ``rte_event_eth_rx_adapter_vector_limits_get`` will be promoted to stable.
254  An 8-byte reserved field will be added to the structure ``rte_event_timer`` to
255  support future extensions.
256
257* eventdev: The structure ``rte_event_eth_rx_adapter_queue_conf`` will be
258  extended to include ``rte_event_eth_rx_adapter_event_vector_config`` elements
259  and the function ``rte_event_eth_rx_adapter_queue_event_vector_config`` will
260  be removed in DPDK 21.11.
261
262  An application can enable event vectorization by passing the desired vector
263  values to the function ``rte_event_eth_rx_adapter_queue_add`` using
264  the structure ``rte_event_eth_rx_adapter_queue_add``.
265
266* eventdev: Reserved bytes of ``rte_event_crypto_request`` is a space holder
267  for ``response_info``. Both should be decoupled for better clarity.
268  New space for ``response_info`` can be made by changing
269  ``rte_event_crypto_metadata`` type to structure from union.
270  This change is targeted for DPDK 21.11.
271
272* metrics: The function ``rte_metrics_init`` will have a non-void return
273  in order to notify errors instead of calling ``rte_exit``.
274
275* cmdline: ``cmdline`` structure will be made opaque to hide platform-specific
276  content. On Linux and FreeBSD, supported prior to DPDK 20.11,
277  original structure will be kept until DPDK 21.11.
278
279* cryptodev: The structure ``rte_crypto_op`` would be updated to reduce
280  reserved bytes to 2 (from 3), and use 1 byte to indicate warnings and other
281  information from the crypto/security operation. This field will be used to
282  communicate events such as soft expiry with IPsec in lookaside mode.
283