xref: /f-stack/dpdk/doc/guides/nics/i40e.rst (revision 2d9fd380)
1..  SPDX-License-Identifier: BSD-3-Clause
2    Copyright(c) 2016 Intel Corporation.
3
4I40E Poll Mode Driver
5======================
6
7The i40e PMD (**librte_net_i40e**) provides poll mode driver support for
810/25/40 Gbps Intel® Ethernet 700 Series Network Adapters based on
9the Intel Ethernet Controller X710/XL710/XXV710 and Intel Ethernet
10Connection X722 (only support part of features).
11
12
13Features
14--------
15
16Features of the i40e PMD are:
17
18- Multiple queues for TX and RX
19- Receiver Side Scaling (RSS)
20- MAC/VLAN filtering
21- Packet type information
22- Flow director
23- Cloud filter
24- Checksum offload
25- VLAN/QinQ stripping and inserting
26- TSO offload
27- Promiscuous mode
28- Multicast mode
29- Port hardware statistics
30- Jumbo frames
31- Link state information
32- Link flow control
33- Mirror on port, VLAN and VSI
34- Interrupt mode for RX
35- Scattered and gather for TX and RX
36- Vector Poll mode driver
37- DCB
38- VMDQ
39- SR-IOV VF
40- Hot plug
41- IEEE1588/802.1AS timestamping
42- VF Daemon (VFD) - EXPERIMENTAL
43- Dynamic Device Personalization (DDP)
44- Queue region configuration
45- Virtual Function Port Representors
46- Malicious Device Drive event catch and notify
47- Generic flow API
48
49Prerequisites
50-------------
51
52- Identifying your adapter using `Intel Support
53  <http://www.intel.com/support>`_ and get the latest NVM/FW images.
54
55- Follow the DPDK :ref:`Getting Started Guide for Linux <linux_gsg>` to setup the basic DPDK environment.
56
57- To get better performance on Intel platforms, please follow the "How to get best performance with NICs on Intel platforms"
58  section of the :ref:`Getting Started Guide for Linux <linux_gsg>`.
59
60- Upgrade the NVM/FW version following the `Intel® Ethernet NVM Update Tool Quick Usage Guide for Linux
61  <https://www-ssl.intel.com/content/www/us/en/embedded/products/networking/nvm-update-tool-quick-linux-usage-guide.html>`_ and `Intel® Ethernet NVM Update Tool: Quick Usage Guide for EFI <https://www.intel.com/content/www/us/en/embedded/products/networking/nvm-update-tool-quick-efi-usage-guide.html>`_ if needed.
62
63- For information about supported media, please refer to this document: `Intel® Ethernet Controller X710/XXV710/XL710 Feature Support Matrix
64  <http://www.intel.com/content/dam/www/public/us/en/documents/release-notes/xl710-ethernet-controller-feature-matrix.pdf>`_.
65
66   .. Note::
67
68      * Some adapters based on the Intel(R) Ethernet Controller 700 Series only
69        support Intel Ethernet Optics modules. On these adapters, other modules are not
70        supported and will not function.
71
72      * For connections based on Intel(R) Ethernet Controller 700 Series,
73        support is dependent on your system board. Please see your vendor for details.
74
75      * In all cases Intel recommends using Intel Ethernet Optics; other modules
76        may function but are not validated by Intel. Contact Intel for supported media types.
77
78Recommended Matching List
79-------------------------
80
81It is highly recommended to upgrade the i40e kernel driver and firmware to
82avoid the compatibility issues with i40e PMD. Here is the suggested matching
83list which has been tested and verified. The detailed information can refer
84to chapter Tested Platforms/Tested NICs in release notes.
85
86For X710/XL710/XXV710,
87
88   +--------------+-----------------------+------------------+
89   | DPDK version | Kernel driver version | Firmware version |
90   +==============+=======================+==================+
91   |    20.11     |         2.13.10       |       8.00       |
92   +--------------+-----------------------+------------------+
93   |    20.08     |         2.12.6        |       7.30       |
94   +--------------+-----------------------+------------------+
95   |    20.05     |         2.11.27       |       7.30       |
96   +--------------+-----------------------+------------------+
97   |    20.02     |         2.10.19       |       7.20       |
98   +--------------+-----------------------+------------------+
99   |    19.11     |         2.9.21        |       7.00       |
100   +--------------+-----------------------+------------------+
101   |    19.08     |         2.8.43        |       7.00       |
102   +--------------+-----------------------+------------------+
103   |    19.05     |         2.7.29        |       6.80       |
104   +--------------+-----------------------+------------------+
105   |    19.02     |         2.7.26        |       6.80       |
106   +--------------+-----------------------+------------------+
107   |    18.11     |         2.4.6         |       6.01       |
108   +--------------+-----------------------+------------------+
109   |    18.08     |         2.4.6         |       6.01       |
110   +--------------+-----------------------+------------------+
111   |    18.05     |         2.4.6         |       6.01       |
112   +--------------+-----------------------+------------------+
113   |    18.02     |         2.4.3         |       6.01       |
114   +--------------+-----------------------+------------------+
115   |    17.11     |         2.1.26        |       6.01       |
116   +--------------+-----------------------+------------------+
117   |    17.08     |         2.0.19        |       6.01       |
118   +--------------+-----------------------+------------------+
119   |    17.05     |         1.5.23        |       5.05       |
120   +--------------+-----------------------+------------------+
121   |    17.02     |         1.5.23        |       5.05       |
122   +--------------+-----------------------+------------------+
123   |    16.11     |         1.5.23        |       5.05       |
124   +--------------+-----------------------+------------------+
125   |    16.07     |         1.4.25        |       5.04       |
126   +--------------+-----------------------+------------------+
127   |    16.04     |         1.4.25        |       5.02       |
128   +--------------+-----------------------+------------------+
129
130
131For X722,
132
133   +--------------+-----------------------+------------------+
134   | DPDK version | Kernel driver version | Firmware version |
135   +==============+=======================+==================+
136   |    20.11     |         2.13.10       |       5.00       |
137   +--------------+-----------------------+------------------+
138   |    20.08     |         2.12.6        |       4.11       |
139   +--------------+-----------------------+------------------+
140   |    20.05     |         2.11.27       |       4.11       |
141   +--------------+-----------------------+------------------+
142   |    20.02     |         2.10.19       |       4.11       |
143   +--------------+-----------------------+------------------+
144   |    19.11     |         2.9.21        |       4.10       |
145   +--------------+-----------------------+------------------+
146   |    19.08     |         2.9.21        |       4.10       |
147   +--------------+-----------------------+------------------+
148   |    19.05     |         2.7.29        |       3.33       |
149   +--------------+-----------------------+------------------+
150   |    19.02     |         2.7.26        |       3.33       |
151   +--------------+-----------------------+------------------+
152   |    18.11     |         2.4.6         |       3.33       |
153   +--------------+-----------------------+------------------+
154
155
156Pre-Installation Configuration
157------------------------------
158
159Config File Options
160~~~~~~~~~~~~~~~~~~~
161
162The following options can be modified in the ``config/rte_config.h`` file.
163
164- ``RTE_LIBRTE_I40E_QUEUE_NUM_PER_PF`` (default ``64``)
165
166  Number of queues reserved for PF.
167
168- ``RTE_LIBRTE_I40E_QUEUE_NUM_PER_VM`` (default ``4``)
169
170  Number of queues reserved for each VMDQ Pool.
171
172Runtime Config Options
173~~~~~~~~~~~~~~~~~~~~~~
174
175- ``Reserved number of Queues per VF`` (default ``4``)
176
177  The number of reserved queue per VF is determined by its host PF. If the
178  PCI address of an i40e PF is aaaa:bb.cc, the number of reserved queues per
179  VF can be configured with EAL parameter like -a aaaa:bb.cc,queue-num-per-vf=n.
180  The value n can be 1, 2, 4, 8 or 16. If no such parameter is configured, the
181  number of reserved queues per VF is 4 by default. If VF request more than
182  reserved queues per VF, PF will able to allocate max to 16 queues after a VF
183  reset.
184
185
186- ``Support multiple driver`` (default ``disable``)
187
188  There was a multiple driver support issue during use of 700 series Ethernet
189  Adapter with both Linux kernel and DPDK PMD. To fix this issue, ``devargs``
190  parameter ``support-multi-driver`` is introduced, for example::
191
192    -a 84:00.0,support-multi-driver=1
193
194  With the above configuration, DPDK PMD will not change global registers, and
195  will switch PF interrupt from IntN to Int0 to avoid interrupt conflict between
196  DPDK and Linux Kernel.
197
198- ``Support VF Port Representor`` (default ``not enabled``)
199
200  The i40e PF PMD supports the creation of VF port representors for the control
201  and monitoring of i40e virtual function devices. Each port representor
202  corresponds to a single virtual function of that device. Using the ``devargs``
203  option ``representor`` the user can specify which virtual functions to create
204  port representors for on initialization of the PF PMD by passing the VF IDs of
205  the VFs which are required.::
206
207  -a DBDF,representor=[0,1,4]
208
209  Currently hot-plugging of representor ports is not supported so all required
210  representors must be specified on the creation of the PF.
211
212- ``Use latest supported vector`` (default ``disable``)
213
214  Latest supported vector path may not always get the best perf so vector path was
215  recommended to use only on later platform. But users may want the latest vector path
216  since it can get better perf in some real work loading cases. So ``devargs`` param
217  ``use-latest-supported-vec`` is introduced, for example::
218
219  -a 84:00.0,use-latest-supported-vec=1
220
221- ``Enable validation for VF message`` (default ``not enabled``)
222
223  The PF counts messages from each VF. If in any period of seconds the message
224  statistic from a VF exceeds maximal limitation, the PF will ignore any new message
225  from that VF for some seconds.
226  Format -- "maximal-message@period-seconds:ignore-seconds"
227  For example::
228
229  -a 84:00.0,vf_msg_cfg=80@120:180
230
231Vector RX Pre-conditions
232~~~~~~~~~~~~~~~~~~~~~~~~
233For Vector RX it is assumed that the number of descriptor rings will be a power
234of 2. With this pre-condition, the ring pointer can easily scroll back to the
235head after hitting the tail without a conditional check. In addition Vector RX
236can use this assumption to do a bit mask using ``ring_size - 1``.
237
238Driver compilation and testing
239------------------------------
240
241Refer to the document :ref:`compiling and testing a PMD for a NIC <pmd_build_and_test>`
242for details.
243
244
245SR-IOV: Prerequisites and sample Application Notes
246--------------------------------------------------
247
248#. Load the kernel module:
249
250   .. code-block:: console
251
252      modprobe i40e
253
254   Check the output in dmesg:
255
256   .. code-block:: console
257
258      i40e 0000:83:00.1 ens802f0: renamed from eth0
259
260#. Bring up the PF ports:
261
262   .. code-block:: console
263
264      ifconfig ens802f0 up
265
266#. Create VF device(s):
267
268   Echo the number of VFs to be created into the ``sriov_numvfs`` sysfs entry
269   of the parent PF.
270
271   Example:
272
273   .. code-block:: console
274
275      echo 2 > /sys/devices/pci0000:00/0000:00:03.0/0000:81:00.0/sriov_numvfs
276
277
278#. Assign VF MAC address:
279
280   Assign MAC address to the VF using iproute2 utility. The syntax is:
281
282   .. code-block:: console
283
284      ip link set <PF netdev id> vf <VF id> mac <macaddr>
285
286   Example:
287
288   .. code-block:: console
289
290      ip link set ens802f0 vf 0 mac a0:b0:c0:d0:e0:f0
291
292#. Assign VF to VM, and bring up the VM.
293   Please see the documentation for the *I40E/IXGBE/IGB Virtual Function Driver*.
294
295#. Running testpmd:
296
297   Follow instructions available in the document
298   :ref:`compiling and testing a PMD for a NIC <pmd_build_and_test>`
299   to run testpmd.
300
301   Example output:
302
303   .. code-block:: console
304
305      ...
306      EAL: PCI device 0000:83:00.0 on NUMA socket 1
307      EAL: probe driver: 8086:1572 rte_i40e_pmd
308      EAL: PCI memory mapped at 0x7f7f80000000
309      EAL: PCI memory mapped at 0x7f7f80800000
310      PMD: eth_i40e_dev_init(): FW 5.0 API 1.5 NVM 05.00.02 eetrack 8000208a
311      Interactive-mode selected
312      Configuring Port 0 (socket 0)
313      ...
314
315      PMD: i40e_dev_rx_queue_setup(): Rx Burst Bulk Alloc Preconditions are
316      satisfied.Rx Burst Bulk Alloc function will be used on port=0, queue=0.
317
318      ...
319      Port 0: 68:05:CA:26:85:84
320      Checking link statuses...
321      Port 0 Link Up - speed 10000 Mbps - full-duplex
322      Done
323
324      testpmd>
325
326
327Sample Application Notes
328------------------------
329
330Vlan filter
331~~~~~~~~~~~
332
333Vlan filter only works when Promiscuous mode is off.
334
335To start ``testpmd``, and add vlan 10 to port 0:
336
337.. code-block:: console
338
339    ./<build_dir>/app/dpdk-testpmd -l 0-15 -n 4 -- -i --forward-mode=mac
340    ...
341
342    testpmd> set promisc 0 off
343    testpmd> rx_vlan add 10 0
344
345
346Flow Director
347~~~~~~~~~~~~~
348
349The Flow Director works in receive mode to identify specific flows or sets of flows and route them to specific queues.
350The Flow Director filters can match the different fields for different type of packet: flow type, specific input set per flow type and the flexible payload.
351
352The default input set of each flow type is::
353
354   ipv4-other : src_ip_address, dst_ip_address
355   ipv4-frag  : src_ip_address, dst_ip_address
356   ipv4-tcp   : src_ip_address, dst_ip_address, src_port, dst_port
357   ipv4-udp   : src_ip_address, dst_ip_address, src_port, dst_port
358   ipv4-sctp  : src_ip_address, dst_ip_address, src_port, dst_port,
359                verification_tag
360   ipv6-other : src_ip_address, dst_ip_address
361   ipv6-frag  : src_ip_address, dst_ip_address
362   ipv6-tcp   : src_ip_address, dst_ip_address, src_port, dst_port
363   ipv6-udp   : src_ip_address, dst_ip_address, src_port, dst_port
364   ipv6-sctp  : src_ip_address, dst_ip_address, src_port, dst_port,
365                verification_tag
366   l2_payload : ether_type
367
368The flex payload is selected from offset 0 to 15 of packet's payload by default, while it is masked out from matching.
369
370Start ``testpmd`` with ``--disable-rss`` and ``--pkt-filter-mode=perfect``:
371
372.. code-block:: console
373
374   ./<build_dir>/app/dpdk-testpmd -l 0-15 -n 4 -- -i --disable-rss \
375                 --pkt-filter-mode=perfect --rxq=8 --txq=8 --nb-cores=8 \
376                 --nb-ports=1
377
378Add a rule to direct ``ipv4-udp`` packet whose ``dst_ip=2.2.2.5, src_ip=2.2.2.3, src_port=32, dst_port=32`` to queue 1:
379
380.. code-block:: console
381
382   testpmd> flow create 0 ingress pattern eth / ipv4 src is 2.2.2.3 \
383            dst is 2.2.2.5 / udp src is 32 dst is 32 / end \
384            actions mark id 1 / queue index 1 / end
385
386Check the flow director status:
387
388.. code-block:: console
389
390   testpmd> show port fdir 0
391
392   ######################## FDIR infos for port 0      ####################
393     MODE:   PERFECT
394     SUPPORTED FLOW TYPE:  ipv4-frag ipv4-tcp ipv4-udp ipv4-sctp ipv4-other
395                           ipv6-frag ipv6-tcp ipv6-udp ipv6-sctp ipv6-other
396			   l2_payload
397     FLEX PAYLOAD INFO:
398     max_len:	    16	        payload_limit: 480
399     payload_unit:  2	        payload_seg:   3
400     bitmask_unit:  2	        bitmask_num:   2
401     MASK:
402       vlan_tci: 0x0000,
403       src_ipv4: 0x00000000,
404       dst_ipv4: 0x00000000,
405       src_port: 0x0000,
406       dst_port: 0x0000
407       src_ipv6: 0x00000000,0x00000000,0x00000000,0x00000000,
408       dst_ipv6: 0x00000000,0x00000000,0x00000000,0x00000000
409     FLEX PAYLOAD SRC OFFSET:
410       L2_PAYLOAD:    0      1	    2	   3	  4	 5	6  ...
411       L3_PAYLOAD:    0      1	    2	   3	  4	 5	6  ...
412       L4_PAYLOAD:    0      1	    2	   3	  4	 5	6  ...
413     FLEX MASK CFG:
414       ipv4-udp:    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
415       ipv4-tcp:    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
416       ipv4-sctp:   00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
417       ipv4-other:  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
418       ipv4-frag:   00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
419       ipv6-udp:    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
420       ipv6-tcp:    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
421       ipv6-sctp:   00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
422       ipv6-other:  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
423       ipv6-frag:   00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
424       l2_payload:  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
425     guarant_count: 1	        best_count:    0
426     guarant_space: 512         best_space:    7168
427     collision:     0	        free:	       0
428     maxhash:	    0	        maxlen:        0
429     add:	    0	        remove:        0
430     f_add:	    0	        f_remove:      0
431
432
433Floating VEB
434~~~~~~~~~~~~~
435
436The Intel® Ethernet 700 Series support a feature called
437"Floating VEB".
438
439A Virtual Ethernet Bridge (VEB) is an IEEE Edge Virtual Bridging (EVB) term
440for functionality that allows local switching between virtual endpoints within
441a physical endpoint and also with an external bridge/network.
442
443A "Floating" VEB doesn't have an uplink connection to the outside world so all
444switching is done internally and remains within the host. As such, this
445feature provides security benefits.
446
447In addition, a Floating VEB overcomes a limitation of normal VEBs where they
448cannot forward packets when the physical link is down. Floating VEBs don't need
449to connect to the NIC port so they can still forward traffic from VF to VF
450even when the physical link is down.
451
452Therefore, with this feature enabled VFs can be limited to communicating with
453each other but not an outside network, and they can do so even when there is
454no physical uplink on the associated NIC port.
455
456To enable this feature, the user should pass a ``devargs`` parameter to the
457EAL, for example::
458
459    -a 84:00.0,enable_floating_veb=1
460
461In this configuration the PMD will use the floating VEB feature for all the
462VFs created by this PF device.
463
464Alternatively, the user can specify which VFs need to connect to this floating
465VEB using the ``floating_veb_list`` argument::
466
467    -a 84:00.0,enable_floating_veb=1,floating_veb_list=1;3-4
468
469In this example ``VF1``, ``VF3`` and ``VF4`` connect to the floating VEB,
470while other VFs connect to the normal VEB.
471
472The current implementation only supports one floating VEB and one regular
473VEB. VFs can connect to a floating VEB or a regular VEB according to the
474configuration passed on the EAL command line.
475
476The floating VEB functionality requires a NIC firmware version of 5.0
477or greater.
478
479Dynamic Device Personalization (DDP)
480~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
481
482The Intel® Ethernet 700 Series except for the Intel Ethernet Connection
483X722 support a feature called "Dynamic Device Personalization (DDP)",
484which is used to configure hardware by downloading a profile to support
485protocols/filters which are not supported by default. The DDP
486functionality requires a NIC firmware version of 6.0 or greater.
487
488Current implementation supports GTP-C/GTP-U/PPPoE/PPPoL2TP/ESP,
489steering can be used with rte_flow API.
490
491GTPv1 package is released, and it can be downloaded from
492https://downloadcenter.intel.com/download/27587.
493
494PPPoE package is released, and it can be downloaded from
495https://downloadcenter.intel.com/download/28040.
496
497ESP-AH package is released, and it can be downloaded from
498https://downloadcenter.intel.com/download/29446.
499
500Load a profile which supports GTP and store backup profile:
501
502.. code-block:: console
503
504   testpmd> ddp add 0 ./gtp.pkgo,./backup.pkgo
505
506Delete a GTP profile and restore backup profile:
507
508.. code-block:: console
509
510   testpmd> ddp del 0 ./backup.pkgo
511
512Get loaded DDP package info list:
513
514.. code-block:: console
515
516   testpmd> ddp get list 0
517
518Display information about a GTP profile:
519
520.. code-block:: console
521
522   testpmd> ddp get info ./gtp.pkgo
523
524Input set configuration
525~~~~~~~~~~~~~~~~~~~~~~~
526Input set for any PCTYPE can be configured with user defined configuration,
527For example, to use only 48bit prefix for IPv6 src address for IPv6 TCP RSS:
528
529.. code-block:: console
530
531   testpmd> port config 0 pctype 43 hash_inset clear all
532   testpmd> port config 0 pctype 43 hash_inset set field 13
533   testpmd> port config 0 pctype 43 hash_inset set field 14
534   testpmd> port config 0 pctype 43 hash_inset set field 15
535
536Queue region configuration
537~~~~~~~~~~~~~~~~~~~~~~~~~~~
538The Intel® Ethernet 700 Series supports a feature of queue regions
539configuration for RSS in the PF, so that different traffic classes or
540different packet classification types can be separated to different
541queues in different queue regions. There is an API for configuration
542of queue regions in RSS with a command line. It can parse the parameters
543of the region index, queue number, queue start index, user priority, traffic
544classes and so on. Depending on commands from the command line, it will call
545i40e private APIs and start the process of setting or flushing the queue
546region configuration. As this feature is specific for i40e only private
547APIs are used. These new ``test_pmd`` commands are as shown below. For
548details please refer to :doc:`../testpmd_app_ug/index`.
549
550.. code-block:: console
551
552   testpmd> set port (port_id) queue-region region_id (value) \
553		queue_start_index (value) queue_num (value)
554   testpmd> set port (port_id) queue-region region_id (value) flowtype (value)
555   testpmd> set port (port_id) queue-region UP (value) region_id (value)
556   testpmd> set port (port_id) queue-region flush (on|off)
557   testpmd> show port (port_id) queue-region
558
559Generic flow API
560~~~~~~~~~~~~~~~~~~~
561
562- ``RSS Flow``
563
564  RSS Flow supports to set hash input set, hash function, enable hash
565  and configure queue region.
566  For example:
567  Configure queue region as queue 0, 1, 2, 3.
568
569  .. code-block:: console
570
571    testpmd> flow create 0 ingress pattern end actions rss types end \
572      queues 0 1 2 3 end / end
573
574  Enable hash and set input set for ipv4-tcp.
575
576  .. code-block:: console
577
578    testpmd> flow create 0 ingress pattern eth / ipv4 / tcp / end \
579      actions rss types ipv4-tcp l3-src-only end queues end / end
580
581  Set symmetric hash enable for flow type ipv4-tcp.
582
583  .. code-block:: console
584
585    testpmd> flow create 0 ingress pattern eth / ipv4 / tcp / end \
586      actions rss types ipv4-tcp end queues end func symmetric_toeplitz / end
587
588  Set hash function as simple xor.
589
590  .. code-block:: console
591
592    testpmd> flow create 0 ingress pattern end actions rss types end \
593      queues end func simple_xor / end
594
595Limitations or Known issues
596---------------------------
597
598MPLS packet classification
599~~~~~~~~~~~~~~~~~~~~~~~~~~
600
601For firmware versions prior to 5.0, MPLS packets are not recognized by the NIC.
602The L2 Payload flow type in flow director can be used to classify MPLS packet
603by using a command in testpmd like:
604
605   testpmd> flow_director_filter 0 mode IP add flow l2_payload ether \
606            0x8847 flexbytes () fwd pf queue <N> fd_id <M>
607
608With the NIC firmware version 5.0 or greater, some limited MPLS support
609is added: Native MPLS (MPLS in Ethernet) skip is implemented, while no
610new packet type, no classification or offload are possible. With this change,
611L2 Payload flow type in flow director cannot be used to classify MPLS packet
612as with previous firmware versions. Meanwhile, the Ethertype filter can be
613used to classify MPLS packet by using a command in testpmd like:
614
615   testpmd> flow create 0 ingress pattern eth type is 0x8847 / end \
616            actions queue index <M> / end
617
61816 Byte RX Descriptor setting on DPDK VF
619~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
620
621Currently the VF's RX descriptor mode is decided by PF. There's no PF-VF
622interface for VF to request the RX descriptor mode, also no interface to notify
623VF its own RX descriptor mode.
624For all available versions of the i40e driver, these drivers don't support 16
625byte RX descriptor. If the Linux i40e kernel driver is used as host driver,
626while DPDK i40e PMD is used as the VF driver, DPDK cannot choose 16 byte receive
627descriptor. The reason is that the RX descriptor is already set to 32 byte by
628the i40e kernel driver.
629In the future, if the Linux i40e driver supports 16 byte RX descriptor, user
630should make sure the DPDK VF uses the same RX descriptor mode, 16 byte or 32
631byte, as the PF driver.
632
633The same rule for DPDK PF + DPDK VF. The PF and VF should use the same RX
634descriptor mode. Or the VF RX will not work.
635
636Receive packets with Ethertype 0x88A8
637~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
638
639Due to the FW limitation, PF can receive packets with Ethertype 0x88A8
640only when floating VEB is disabled.
641
642Incorrect Rx statistics when packet is oversize
643~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
644
645When a packet is over maximum frame size, the packet is dropped.
646However, the Rx statistics, when calling `rte_eth_stats_get` incorrectly
647shows it as received.
648
649RX/TX statistics may be incorrect when register overflowed
650~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
651
652The rx_bytes/tx_bytes statistics register is 48 bit length.
653Although this limitation is enlarged to 64 bit length on the software side,
654but there is no way to detect if the overflow occurred more than once.
655So rx_bytes/tx_bytes statistics data is correct when statistics are
656updated at least once between two overflows.
657
658VF & TC max bandwidth setting
659~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
660
661The per VF max bandwidth and per TC max bandwidth cannot be enabled in parallel.
662The behavior is different when handling per VF and per TC max bandwidth setting.
663When enabling per VF max bandwidth, SW will check if per TC max bandwidth is
664enabled. If so, return failure.
665When enabling per TC max bandwidth, SW will check if per VF max bandwidth
666is enabled. If so, disable per VF max bandwidth and continue with per TC max
667bandwidth setting.
668
669TC TX scheduling mode setting
670~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
671
672There are 2 TX scheduling modes for TCs, round robin and strict priority mode.
673If a TC is set to strict priority mode, it can consume unlimited bandwidth.
674It means if APP has set the max bandwidth for that TC, it comes to no
675effect.
676It's suggested to set the strict priority mode for a TC that is latency
677sensitive but no consuming much bandwidth.
678
679VF performance is impacted by PCI extended tag setting
680~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
681
682To reach maximum NIC performance in the VF the PCI extended tag must be
683enabled. The DPDK i40e PF driver will set this feature during initialization,
684but the kernel PF driver does not. So when running traffic on a VF which is
685managed by the kernel PF driver, a significant NIC performance downgrade has
686been observed (for 64 byte packets, there is about 25% line-rate downgrade for
687a 25GbE device and about 35% for a 40GbE device).
688
689For kernel version >= 4.11, the kernel's PCI driver will enable the extended
690tag if it detects that the device supports it. So by default, this is not an
691issue. For kernels <= 4.11 or when the PCI extended tag is disabled it can be
692enabled using the steps below.
693
694#. Get the current value of the PCI configure register::
695
696      setpci -s <XX:XX.X> a8.w
697
698#. Set bit 8::
699
700      value = value | 0x100
701
702#. Set the PCI configure register with new value::
703
704      setpci -s <XX:XX.X> a8.w=<value>
705
706Vlan strip of VF
707~~~~~~~~~~~~~~~~
708
709The VF vlan strip function is only supported in the i40e kernel driver >= 2.1.26.
710
711DCB function
712~~~~~~~~~~~~
713
714DCB works only when RSS is enabled.
715
716Global configuration warning
717~~~~~~~~~~~~~~~~~~~~~~~~~~~~
718
719I40E PMD will set some global registers to enable some function or set some
720configure. Then when using different ports of the same NIC with Linux kernel
721and DPDK, the port with Linux kernel will be impacted by the port with DPDK.
722For example, register I40E_GL_SWT_L2TAGCTRL is used to control L2 tag, i40e
723PMD uses I40E_GL_SWT_L2TAGCTRL to set vlan TPID. If setting TPID in port A
724with DPDK, then the configuration will also impact port B in the NIC with
725kernel driver, which don't want to use the TPID.
726So PMD reports warning to clarify what is changed by writing global register.
727
728Cloud Filter
729~~~~~~~~~~~~
730
731When programming cloud filters for IPv4/6_UDP/TCP/SCTP with SRC port only or DST port only,
732it will make any cloud filter using inner_vlan or tunnel key invalid. Default configuration will be
733recovered only by NIC core reset.
734
735High Performance of Small Packets on 40GbE NIC
736----------------------------------------------
737
738As there might be firmware fixes for performance enhancement in latest version
739of firmware image, the firmware update might be needed for getting high performance.
740Check the Intel support website for the latest firmware updates.
741Users should consult the release notes specific to a DPDK release to identify
742the validated firmware version for a NIC using the i40e driver.
743
744Use 16 Bytes RX Descriptor Size
745~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
746
747As i40e PMD supports both 16 and 32 bytes RX descriptor sizes, and 16 bytes size can provide helps to high performance of small packets.
748In ``config/rte_config.h`` set the following to use 16 bytes size RX descriptors::
749
750   #define RTE_LIBRTE_I40E_16BYTE_RX_DESC 1
751
752Input set requirement of each pctype for FDIR
753~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
754
755Each PCTYPE can only have one specific FDIR input set at one time.
756For example, if creating 2 rte_flow rules with different input set for one PCTYPE,
757it will fail and return the info "Conflict with the first rule's input set",
758which means the current rule's input set conflicts with the first rule's.
759Remove the first rule if want to change the input set of the PCTYPE.
760
761Example of getting best performance with l3fwd example
762------------------------------------------------------
763
764The following is an example of running the DPDK ``l3fwd`` sample application to get high performance with a
765server with Intel Xeon processors and Intel Ethernet CNA XL710.
766
767The example scenario is to get best performance with two Intel Ethernet CNA XL710 40GbE ports.
768See :numref:`figure_intel_perf_test_setup` for the performance test setup.
769
770.. _figure_intel_perf_test_setup:
771
772.. figure:: img/intel_perf_test_setup.*
773
774   Performance Test Setup
775
776
7771. Add two Intel Ethernet CNA XL710 to the platform, and use one port per card to get best performance.
778   The reason for using two NICs is to overcome a PCIe v3.0 limitation since it cannot provide 80GbE bandwidth
779   for two 40GbE ports, but two different PCIe v3.0 x8 slot can.
780   Refer to the sample NICs output above, then we can select ``82:00.0`` and ``85:00.0`` as test ports::
781
782      82:00.0 Ethernet [0200]: Intel XL710 for 40GbE QSFP+ [8086:1583]
783      85:00.0 Ethernet [0200]: Intel XL710 for 40GbE QSFP+ [8086:1583]
784
7852. Connect the ports to the traffic generator. For high speed testing, it's best to use a hardware traffic generator.
786
7873. Check the PCI devices numa node (socket id) and get the cores number on the exact socket id.
788   In this case, ``82:00.0`` and ``85:00.0`` are both in socket 1, and the cores on socket 1 in the referenced platform
789   are 18-35 and 54-71.
790   Note: Don't use 2 logical cores on the same core (e.g core18 has 2 logical cores, core18 and core54), instead, use 2 logical
791   cores from different cores (e.g core18 and core19).
792
7934. Bind these two ports to igb_uio.
794
7955. As to Intel Ethernet CNA XL710 40GbE port, we need at least two queue pairs to achieve best performance, then two queues per port
796   will be required, and each queue pair will need a dedicated CPU core for receiving/transmitting packets.
797
7986. The DPDK sample application ``l3fwd`` will be used for performance testing, with using two ports for bi-directional forwarding.
799   Compile the ``l3fwd sample`` with the default lpm mode.
800
8017. The command line of running l3fwd would be something like the following::
802
803      ./dpdk-l3fwd -l 18-21 -n 4 -a 82:00.0 -a 85:00.0 \
804              -- -p 0x3 --config '(0,0,18),(0,1,19),(1,0,20),(1,1,21)'
805
806   This means that the application uses core 18 for port 0, queue pair 0 forwarding, core 19 for port 0, queue pair 1 forwarding,
807   core 20 for port 1, queue pair 0 forwarding, and core 21 for port 1, queue pair 1 forwarding.
808
8098. Configure the traffic at a traffic generator.
810
811   * Start creating a stream on packet generator.
812
813   * Set the Ethernet II type to 0x0800.
814
815Tx bytes affected by the link status change
816~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
817
818For firmware versions prior to 6.01 for X710 series and 3.33 for X722 series, the tx_bytes statistics data is affected by
819the link down event. Each time the link status changes to down, the tx_bytes decreases 110 bytes.
820