Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   1) .. SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   2) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   3) =============
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   4) Devlink DPIPE
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   5) =============
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   6) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   7) Background
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   8) ==========
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   9) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  10) While performing the hardware offloading process, much of the hardware
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  11) specifics cannot be presented. These details are useful for debugging, and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  12) ``devlink-dpipe`` provides a standardized way to provide visibility into the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  13) offloading process.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  14) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  15) For example, the routing longest prefix match (LPM) algorithm used by the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  16) Linux kernel may differ from the hardware implementation. The pipeline debug
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  17) API (DPIPE) is aimed at providing the user visibility into the ASIC's
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  18) pipeline in a generic way.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  19) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  20) The hardware offload process is expected to be done in a way that the user
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  21) should not be able to distinguish between the hardware vs. software
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  22) implementation. In this process, hardware specifics are neglected. In
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  23) reality those details can have lots of meaning and should be exposed in some
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  24) standard way.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  25) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  26) This problem is made even more complex when one wishes to offload the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  27) control path of the whole networking stack to a switch ASIC. Due to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  28) differences in the hardware and software models some processes cannot be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  29) represented correctly.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  30) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  31) One example is the kernel's LPM algorithm which in many cases differs
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  32) greatly to the hardware implementation. The configuration API is the same,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  33) but one cannot rely on the Forward Information Base (FIB) to look like the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  34) Level Path Compression trie (LPC-trie) in hardware.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  35) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  36) In many situations trying to analyze systems failure solely based on the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  37) kernel's dump may not be enough. By combining this data with complementary
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  38) information about the underlying hardware, this debugging can be made
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  39) easier; additionally, the information can be useful when debugging
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  40) performance issues.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  41) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  42) Overview
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  43) ========
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  44) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  45) The ``devlink-dpipe`` interface closes this gap. The hardware's pipeline is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  46) modeled as a graph of match/action tables. Each table represents a specific
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  47) hardware block. This model is not new, first being used by the P4 language.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  48) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  49) Traditionally it has been used as an alternative model for hardware
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  50) configuration, but the ``devlink-dpipe`` interface uses it for visibility
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  51) purposes as a standard complementary tool. The system's view from
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  52) ``devlink-dpipe`` should change according to the changes done by the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  53) standard configuration tools.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  54) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  55) For example, it’s quiet common to  implement Access Control Lists (ACL)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  56) using Ternary Content Addressable Memory (TCAM). The TCAM memory can be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  57) divided into TCAM regions. Complex TC filters can have multiple rules with
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  58) different priorities and different lookup keys. On the other hand hardware
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  59) TCAM regions have a predefined lookup key. Offloading the TC filter rules
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  60) using TCAM engine can result in multiple TCAM regions being interconnected
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  61) in a chain (which may affect the data path latency). In response to a new TC
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  62) filter new tables should be created describing those regions.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  63) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  64) Model
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  65) =====
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  66) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  67) The ``DPIPE`` model introduces several objects:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  68) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  69)   * headers
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  70)   * tables
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  71)   * entries
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  72) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  73) A ``header`` describes packet formats and provides names for fields within
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  74) the packet. A ``table`` describes hardware blocks. An ``entry`` describes
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  75) the actual content of a specific table.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  76) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  77) The hardware pipeline is not port specific, but rather describes the whole
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  78) ASIC. Thus it is tied to the top of the ``devlink`` infrastructure.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  79) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  80) Drivers can register and unregister tables at run time, in order to support
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  81) dynamic behavior. This dynamic behavior is mandatory for describing hardware
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  82) blocks like TCAM regions which can be allocated and freed dynamically.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  83) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  84) ``devlink-dpipe`` generally is not intended for configuration. The exception
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  85) is hardware counting for a specific table.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  86) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  87) The following commands are used to obtain the ``dpipe`` objects from
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  88) userspace:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  89) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  90)   * ``table_get``: Receive a table's description.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  91)   * ``headers_get``: Receive a device's supported headers.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  92)   * ``entries_get``: Receive a table's current entries.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  93)   * ``counters_set``: Enable or disable counters on a table.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  94) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  95) Table
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  96) -----
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  97) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  98) The driver should implement the following operations for each table:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  99) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100)   * ``matches_dump``: Dump the supported matches.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101)   * ``actions_dump``: Dump the supported actions.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102)   * ``entries_dump``: Dump the actual content of the table.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103)   * ``counters_set_update``: Synchronize hardware with counters enabled or
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104)     disabled.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) Header/Field
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) ------------
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) In a similar way to P4 headers and fields are used to describe a table's
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) behavior. There is a slight difference between the standard protocol headers
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) and specific ASIC metadata. The protocol headers should be declared in the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) ``devlink`` core API. On the other hand ASIC meta data is driver specific
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) and should be defined in the driver. Additionally, each driver-specific
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) devlink documentation file should document the driver-specific ``dpipe``
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) headers it implements. The headers and fields are identified by enumeration.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) In order to provide further visibility some ASIC metadata fields could be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) mapped to kernel objects. For example, internal router interface indexes can
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) be directly mapped to the net device ifindex. FIB table indexes used by
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) different Virtual Routing and Forwarding (VRF) tables can be mapped to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) internal routing table indexes.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) Match
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) -----
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) Matches are kept primitive and close to hardware operation. Match types like
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) LPM are not supported due to the fact that this is exactly a process we wish
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) to describe in full detail. Example of matches:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130)   * ``field_exact``: Exact match on a specific field.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131)   * ``field_exact_mask``: Exact match on a specific field after masking.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132)   * ``field_range``: Match on a specific range.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) The id's of the header and the field should be specified in order to
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) identify the specific field. Furthermore, the header index should be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) specified in order to distinguish multiple headers of the same type in a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) packet (tunneling).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) Action
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) ------
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) Similar to match, the actions are kept primitive and close to hardware
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) operation. For example:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145)   * ``field_modify``: Modify the field value.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146)   * ``field_inc``: Increment the field value.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147)   * ``push_header``: Add a header.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148)   * ``pop_header``: Remove a header.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) Entry
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) -----
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) Entries of a specific table can be dumped on demand. Each eentry is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) identified with an index and its properties are described by a list of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) match/action values and specific counter. By dumping the tables content the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) interactions between tables can be resolved.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) Abstraction Example
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) ===================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) The following is an example of the abstraction model of the L3 part of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) Mellanox Spectrum ASIC. The blocks are described in the order they appear in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) the pipeline. The table sizes in the following examples are not real
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) hardware sizes and are provided for demonstration purposes.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) LPM
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) ---
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) The LPM algorithm can be implemented as a list of hash tables. Each hash
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) table contains routes with the same prefix length. The root of the list is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) /32, and in case of a miss the hardware will continue to the next hash
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) table. The depth of the search will affect the data path latency.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) In case of a hit the entry contains information about the next stage of the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) pipeline which resolves the MAC address. The next stage can be either local
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) host table for directly connected routes, or adjacency table for next-hops.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) The ``meta.lpm_prefix`` field is used to connect two LPM tables.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) .. code::
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181)     table lpm_prefix_16 {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182)       size: 4096,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183)       counters_enabled: true,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184)       match: { meta.vr_id: exact,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185)                ipv4.dst_addr: exact_mask,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186)                ipv6.dst_addr: exact_mask,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187)                meta.lpm_prefix: exact },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188)       action: { meta.adj_index: set,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189)                 meta.adj_group_size: set,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190)                 meta.rif_port: set,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191)                 meta.lpm_prefix: set },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192)     }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) Local Host
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) ----------
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) In the case of local routes the LPM lookup already resolves the egress
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) router interface (RIF), yet the exact MAC address is not known. The local
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) host table is a hash table combining the output interface id with
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) destination IP address as a key. The result is the MAC address.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) .. code::
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204)     table local_host {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205)       size: 4096,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206)       counters_enabled: true,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207)       match: { meta.rif_port: exact,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208)                ipv4.dst_addr: exact},
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209)       action: { ethernet.daddr: set }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210)     }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) Adjacency
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) ---------
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) In case of remote routes this table does the ECMP. The LPM lookup results in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) ECMP group size and index that serves as a global offset into this table.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) Concurrently a hash of the packet is generated. Based on the ECMP group size
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) and the packet's hash a local offset is generated. Multiple LPM entries can
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) point to the same adjacency group.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) .. code::
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223)     table adjacency {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224)       size: 4096,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225)       counters_enabled: true,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226)       match: { meta.adj_index: exact,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227)                meta.adj_group_size: exact,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228)                meta.packet_hash_index: exact },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229)       action: { ethernet.daddr: set,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230)                 meta.erif: set }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231)     }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) ERIF
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234) ----
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) In case the egress RIF and destination MAC have been resolved by previous
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) tables this table does multiple operations like TTL decrease and MTU check.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) Then the decision of forward/drop is taken and the port L3 statistics are
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) updated based on the packet's type (broadcast, unicast, multicast).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) .. code::
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243)     table erif {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244)       size: 800,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245)       counters_enabled: true,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246)       match: { meta.rif_port: exact,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247)                meta.is_l3_unicast: exact,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248)                meta.is_l3_broadcast: exact,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249)                meta.is_l3_multicast, exact },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250)       action: { meta.l3_drop: set,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251)                 meta.l3_forward: set }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252)     }