Ѝsphinx.addnodesdocument)}( rawsourcechildren]( translations LanguagesNode)}(hhh](h pending_xref)}(hhh]docutils.nodesTextChinese (Simplified)}parenthsba attributes}(ids]classes]names]dupnames]backrefs] refdomainstdreftypedoc reftarget4/translations/zh_CN/networking/devlink/devlink-dpipemodnameN classnameN refexplicitutagnamehhh ubh)}(hhh]hChinese (Traditional)}hh2sbah}(h]h ]h"]h$]h&] refdomainh)reftypeh+ reftarget4/translations/zh_TW/networking/devlink/devlink-dpipemodnameN classnameN refexplicituh1hhh ubh)}(hhh]hItalian}hhFsbah}(h]h ]h"]h$]h&] refdomainh)reftypeh+ reftarget4/translations/it_IT/networking/devlink/devlink-dpipemodnameN classnameN refexplicituh1hhh ubh)}(hhh]hJapanese}hhZsbah}(h]h ]h"]h$]h&] refdomainh)reftypeh+ reftarget4/translations/ja_JP/networking/devlink/devlink-dpipemodnameN classnameN refexplicituh1hhh ubh)}(hhh]hKorean}hhnsbah}(h]h ]h"]h$]h&] refdomainh)reftypeh+ reftarget4/translations/ko_KR/networking/devlink/devlink-dpipemodnameN classnameN refexplicituh1hhh ubh)}(hhh]hPortuguese (Brazilian)}hhsbah}(h]h ]h"]h$]h&] refdomainh)reftypeh+ reftarget4/translations/pt_BR/networking/devlink/devlink-dpipemodnameN classnameN refexplicituh1hhh ubh)}(hhh]hSpanish}hhsbah}(h]h ]h"]h$]h&] refdomainh)reftypeh+ reftarget4/translations/sp_SP/networking/devlink/devlink-dpipemodnameN classnameN refexplicituh1hhh ubeh}(h]h ]h"]h$]h&]current_languageEnglishuh1h hh _documenthsourceNlineNubhcomment)}(h SPDX-License-Identifier: GPL-2.0h]h SPDX-License-Identifier: GPL-2.0}hhsbah}(h]h ]h"]h$]h&] xml:spacepreserveuh1hhhhhhN/var/lib/git/docbuild/linux/Documentation/networking/devlink/devlink-dpipe.rsthKubhsection)}(hhh](htitle)}(h Devlink DPIPEh]h Devlink DPIPE}(hhhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhhhhhKubh)}(hhh](h)}(h Backgroundh]h Background}(hhhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhhhhhKubh paragraph)}(hWhile performing the hardware offloading process, much of the hardware specifics cannot be presented. These details are useful for debugging, and ``devlink-dpipe`` provides a standardized way to provide visibility into the offloading process.h](hWhile performing the hardware offloading process, much of the hardware specifics cannot be presented. These details are useful for debugging, and }(hhhhhNhNubhliteral)}(h``devlink-dpipe``h]h devlink-dpipe}(hhhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhubhO provides a standardized way to provide visibility into the offloading process.}(hhhhhNhNubeh}(h]h ]h"]h$]h&]uh1hhhhK hhhhubh)}(hFor example, the routing longest prefix match (LPM) algorithm used by the Linux kernel may differ from the hardware implementation. The pipeline debug API (DPIPE) is aimed at providing the user visibility into the ASIC's pipeline in a generic way.h]hFor example, the routing longest prefix match (LPM) algorithm used by the Linux kernel may differ from the hardware implementation. The pipeline debug API (DPIPE) is aimed at providing the user visibility into the ASIC’s pipeline in a generic way.}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhhhhubh)}(hX/The hardware offload process is expected to be done in a way that the user should not be able to distinguish between the hardware vs. software implementation. In this process, hardware specifics are neglected. In reality those details can have lots of meaning and should be exposed in some standard way.h]hX/The hardware offload process is expected to be done in a way that the user should not be able to distinguish between the hardware vs. software implementation. In this process, hardware specifics are neglected. In reality those details can have lots of meaning and should be exposed in some standard way.}(hj hhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhhhhubh)}(hThis problem is made even more complex when one wishes to offload the control path of the whole networking stack to a switch ASIC. Due to differences in the hardware and software models some processes cannot be represented correctly.h]hThis problem is made even more complex when one wishes to offload the control path of the whole networking stack to a switch ASIC. Due to differences in the hardware and software models some processes cannot be represented correctly.}(hj.hhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhhhhubh)}(hXOne example is the kernel's LPM algorithm which in many cases differs greatly to the hardware implementation. The configuration API is the same, but one cannot rely on the Forward Information Base (FIB) to look like the Level Path Compression trie (LPC-trie) in hardware.h]hXOne example is the kernel’s LPM algorithm which in many cases differs greatly to the hardware implementation. The configuration API is the same, but one cannot rely on the Forward Information Base (FIB) to look like the Level Path Compression trie (LPC-trie) in hardware.}(hj<hhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhhhhubh)}(hX0In many situations trying to analyze systems failure solely based on the kernel's dump may not be enough. By combining this data with complementary information about the underlying hardware, this debugging can be made easier; additionally, the information can be useful when debugging performance issues.h]hX2In many situations trying to analyze systems failure solely based on the kernel’s dump may not be enough. By combining this data with complementary information about the underlying hardware, this debugging can be made easier; additionally, the information can be useful when debugging performance issues.}(hjJhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhK$hhhhubeh}(h] backgroundah ]h"] backgroundah$]h&]uh1hhhhhhhhKubh)}(hhh](h)}(hOverviewh]hOverview}(hjchhhNhNubah}(h]h ]h"]h$]h&]uh1hhj`hhhhhK+ubh)}(hThe ``devlink-dpipe`` interface closes this gap. The hardware's pipeline is modeled as a graph of match/action tables. Each table represents a specific hardware block. This model is not new, first being used by the P4 language.h](hThe }(hjqhhhNhNubh)}(h``devlink-dpipe``h]h devlink-dpipe}(hjyhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjqubh interface closes this gap. The hardware’s pipeline is modeled as a graph of match/action tables. Each table represents a specific hardware block. This model is not new, first being used by the P4 language.}(hjqhhhNhNubeh}(h]h ]h"]h$]h&]uh1hhhhK-hj`hhubh)}(hX2Traditionally it has been used as an alternative model for hardware configuration, but the ``devlink-dpipe`` interface uses it for visibility purposes as a standard complementary tool. The system's view from ``devlink-dpipe`` should change according to the changes done by the standard configuration tools.h](h[Traditionally it has been used as an alternative model for hardware configuration, but the }(hjhhhNhNubh)}(h``devlink-dpipe``h]h devlink-dpipe}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjubhf interface uses it for visibility purposes as a standard complementary tool. The system’s view from }(hjhhhNhNubh)}(h``devlink-dpipe``h]h devlink-dpipe}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjubhQ should change according to the changes done by the standard configuration tools.}(hjhhhNhNubeh}(h]h ]h"]h$]h&]uh1hhhhK1hj`hhubh)}(hXGFor example, it’s quite common to implement Access Control Lists (ACL) using Ternary Content Addressable Memory (TCAM). The TCAM memory can be divided into TCAM regions. Complex TC filters can have multiple rules with different priorities and different lookup keys. On the other hand hardware TCAM regions have a predefined lookup key. Offloading the TC filter rules using TCAM engine can result in multiple TCAM regions being interconnected in a chain (which may affect the data path latency). In response to a new TC filter new tables should be created describing those regions.h]hXGFor example, it’s quite common to implement Access Control Lists (ACL) using Ternary Content Addressable Memory (TCAM). The TCAM memory can be divided into TCAM regions. Complex TC filters can have multiple rules with different priorities and different lookup keys. On the other hand hardware TCAM regions have a predefined lookup key. Offloading the TC filter rules using TCAM engine can result in multiple TCAM regions being interconnected in a chain (which may affect the data path latency). In response to a new TC filter new tables should be created describing those regions.}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhK7hj`hhubeh}(h]overviewah ]h"]overviewah$]h&]uh1hhhhhhhhK+ubh)}(hhh](h)}(hModelh]hModel}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjhhhhhKAubh)}(h/The ``DPIPE`` model introduces several objects:h](hThe }(hjhhhNhNubh)}(h ``DPIPE``h]hDPIPE}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjubh" model introduces several objects:}(hjhhhNhNubeh}(h]h ]h"]h$]h&]uh1hhhhKChjhhubh block_quote)}(h* headers * tables * entries h]h bullet_list)}(hhh](h list_item)}(hheadersh]h)}(hjh]hheaders}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKEhjubah}(h]h ]h"]h$]h&]uh1jhjubj)}(htablesh]h)}(hj0h]htables}(hj2hhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKFhj.ubah}(h]h ]h"]h$]h&]uh1jhjubj)}(hentries h]h)}(hentriesh]hentries}(hjIhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKGhjEubah}(h]h ]h"]h$]h&]uh1jhjubeh}(h]h ]h"]h$]h&]bullet*uh1jhhhKEhj ubah}(h]h ]h"]h$]h&]uh1j hhhKEhjhhubh)}(hA ``header`` describes packet formats and provides names for fields within the packet. A ``table`` describes hardware blocks. An ``entry`` describes the actual content of a specific table.h](hA }(hjkhhhNhNubh)}(h ``header``h]hheader}(hjshhhNhNubah}(h]h ]h"]h$]h&]uh1hhjkubhM describes packet formats and provides names for fields within the packet. A }(hjkhhhNhNubh)}(h ``table``h]htable}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjkubh describes hardware blocks. An }(hjkhhhNhNubh)}(h ``entry``h]hentry}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjkubh2 describes the actual content of a specific table.}(hjkhhhNhNubeh}(h]h ]h"]h$]h&]uh1hhhhKIhjhhubh)}(hThe hardware pipeline is not port specific, but rather describes the whole ASIC. Thus it is tied to the top of the ``devlink`` infrastructure.h](hsThe hardware pipeline is not port specific, but rather describes the whole ASIC. Thus it is tied to the top of the }(hjhhhNhNubh)}(h ``devlink``h]hdevlink}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjubh infrastructure.}(hjhhhNhNubeh}(h]h ]h"]h$]h&]uh1hhhhKMhjhhubh)}(hDrivers can register and unregister tables at run time, in order to support dynamic behavior. This dynamic behavior is mandatory for describing hardware blocks like TCAM regions which can be allocated and freed dynamically.h]hDrivers can register and unregister tables at run time, in order to support dynamic behavior. This dynamic behavior is mandatory for describing hardware blocks like TCAM regions which can be allocated and freed dynamically.}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKPhjhhubh)}(hw``devlink-dpipe`` generally is not intended for configuration. The exception is hardware counting for a specific table.h](h)}(h``devlink-dpipe``h]h devlink-dpipe}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjubhf generally is not intended for configuration. The exception is hardware counting for a specific table.}(hjhhhNhNubeh}(h]h ]h"]h$]h&]uh1hhhhKThjhhubh)}(hOThe following commands are used to obtain the ``dpipe`` objects from userspace:h](h.The following commands are used to obtain the }(hjhhhNhNubh)}(h ``dpipe``h]hdpipe}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjubh objects from userspace:}(hjhhhNhNubeh}(h]h ]h"]h$]h&]uh1hhhhKWhjhhubj )}(h* ``table_get``: Receive a table's description. * ``headers_get``: Receive a device's supported headers. * ``entries_get``: Receive a table's current entries. * ``counters_set``: Enable or disable counters on a table. h]j)}(hhh](j)}(h-``table_get``: Receive a table's description.h]h)}(hj"h](h)}(h ``table_get``h]h table_get}(hj'hhhNhNubah}(h]h ]h"]h$]h&]uh1hhj$ubh": Receive a table’s description.}(hj$hhhNhNubeh}(h]h ]h"]h$]h&]uh1hhhhKZhj ubah}(h]h ]h"]h$]h&]uh1jhjubj)}(h6``headers_get``: Receive a device's supported headers.h]h)}(hjGh](h)}(h``headers_get``h]h headers_get}(hjLhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjIubh): Receive a device’s supported headers.}(hjIhhhNhNubeh}(h]h ]h"]h$]h&]uh1hhhhK[hjEubah}(h]h ]h"]h$]h&]uh1jhjubj)}(h3``entries_get``: Receive a table's current entries.h]h)}(hjlh](h)}(h``entries_get``h]h entries_get}(hjqhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjnubh&: Receive a table’s current entries.}(hjnhhhNhNubeh}(h]h ]h"]h$]h&]uh1hhhhK\hjjubah}(h]h ]h"]h$]h&]uh1jhjubj)}(h9``counters_set``: Enable or disable counters on a table. h]h)}(h8``counters_set``: Enable or disable counters on a table.h](h)}(h``counters_set``h]h counters_set}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjubh(: Enable or disable counters on a table.}(hjhhhNhNubeh}(h]h ]h"]h$]h&]uh1hhhhK]hjubah}(h]h ]h"]h$]h&]uh1jhjubeh}(h]h ]h"]h$]h&]jcjduh1jhhhKZhjubah}(h]h ]h"]h$]h&]uh1j hhhKZhjhhubh)}(hhh](h)}(hTableh]hTable}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjhhhhhK`ubh)}(hDThe driver should implement the following operations for each table:h]hDThe driver should implement the following operations for each table:}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKbhjhhubj )}(h* ``matches_dump``: Dump the supported matches. * ``actions_dump``: Dump the supported actions. * ``entries_dump``: Dump the actual content of the table. * ``counters_set_update``: Synchronize hardware with counters enabled or disabled. h]j)}(hhh](j)}(h-``matches_dump``: Dump the supported matches.h]h)}(hjh](h)}(h``matches_dump``h]h matches_dump}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjubh: Dump the supported matches.}(hjhhhNhNubeh}(h]h ]h"]h$]h&]uh1hhhhKdhjubah}(h]h ]h"]h$]h&]uh1jhjubj)}(h-``actions_dump``: Dump the supported actions.h]h)}(hjh](h)}(h``actions_dump``h]h actions_dump}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjubh: Dump the supported actions.}(hjhhhNhNubeh}(h]h ]h"]h$]h&]uh1hhhhKehj ubah}(h]h ]h"]h$]h&]uh1jhjubj)}(h7``entries_dump``: Dump the actual content of the table.h]h)}(hj3h](h)}(h``entries_dump``h]h entries_dump}(hj8hhhNhNubah}(h]h ]h"]h$]h&]uh1hhj5ubh': Dump the actual content of the table.}(hj5hhhNhNubeh}(h]h ]h"]h$]h&]uh1hhhhKfhj1ubah}(h]h ]h"]h$]h&]uh1jhjubj)}(hQ``counters_set_update``: Synchronize hardware with counters enabled or disabled. h]h)}(hP``counters_set_update``: Synchronize hardware with counters enabled or disabled.h](h)}(h``counters_set_update``h]hcounters_set_update}(hj^hhhNhNubah}(h]h ]h"]h$]h&]uh1hhjZubh9: Synchronize hardware with counters enabled or disabled.}(hjZhhhNhNubeh}(h]h ]h"]h$]h&]uh1hhhhKghjVubah}(h]h ]h"]h$]h&]uh1jhjubeh}(h]h ]h"]h$]h&]jcjduh1jhhhKdhjubah}(h]h ]h"]h$]h&]uh1j hhhKdhjhhubeh}(h]tableah ]h"]tableah$]h&]uh1hhjhhhhhK`ubh)}(hhh](h)}(h Header/Fieldh]h Header/Field}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjhhhhhKkubh)}(hXIn a similar way to P4 headers and fields are used to describe a table's behavior. There is a slight difference between the standard protocol headers and specific ASIC metadata. The protocol headers should be declared in the ``devlink`` core API. On the other hand ASIC meta data is driver specific and should be defined in the driver. Additionally, each driver-specific devlink documentation file should document the driver-specific ``dpipe`` headers it implements. The headers and fields are identified by enumeration.h](hIn a similar way to P4 headers and fields are used to describe a table’s behavior. There is a slight difference between the standard protocol headers and specific ASIC metadata. The protocol headers should be declared in the }(hjhhhNhNubh)}(h ``devlink``h]hdevlink}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjubh core API. On the other hand ASIC meta data is driver specific and should be defined in the driver. Additionally, each driver-specific devlink documentation file should document the driver-specific }(hjhhhNhNubh)}(h ``dpipe``h]hdpipe}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjubhM headers it implements. The headers and fields are identified by enumeration.}(hjhhhNhNubeh}(h]h ]h"]h$]h&]uh1hhhhKmhjhhubh)}(hXEIn order to provide further visibility some ASIC metadata fields could be mapped to kernel objects. For example, internal router interface indexes can be directly mapped to the net device ifindex. FIB table indexes used by different Virtual Routing and Forwarding (VRF) tables can be mapped to internal routing table indexes.h]hXEIn order to provide further visibility some ASIC metadata fields could be mapped to kernel objects. For example, internal router interface indexes can be directly mapped to the net device ifindex. FIB table indexes used by different Virtual Routing and Forwarding (VRF) tables can be mapped to internal routing table indexes.}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKuhjhhubeh}(h] header-fieldah ]h"] header/fieldah$]h&]uh1hhjhhhhhKkubh)}(hhh](h)}(hMatchh]hMatch}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjhhhhhK|ubh)}(hMatches are kept primitive and close to hardware operation. Match types like LPM are not supported due to the fact that this is exactly a process we wish to describe in full detail. Example of matches:h]hMatches are kept primitive and close to hardware operation. Match types like LPM are not supported due to the fact that this is exactly a process we wish to describe in full detail. Example of matches:}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhK~hjhhubj )}(h* ``field_exact``: Exact match on a specific field. * ``field_exact_mask``: Exact match on a specific field after masking. * ``field_range``: Match on a specific range. h]j)}(hhh](j)}(h1``field_exact``: Exact match on a specific field.h]h)}(hjh](h)}(h``field_exact``h]h field_exact}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjubh": Exact match on a specific field.}(hjhhhNhNubeh}(h]h ]h"]h$]h&]uh1hhhhKhjubah}(h]h ]h"]h$]h&]uh1jhj ubj)}(hD``field_exact_mask``: Exact match on a specific field after masking.h]h)}(hj6h](h)}(h``field_exact_mask``h]hfield_exact_mask}(hj;hhhNhNubah}(h]h ]h"]h$]h&]uh1hhj8ubh0: Exact match on a specific field after masking.}(hj8hhhNhNubeh}(h]h ]h"]h$]h&]uh1hhhhKhj4ubah}(h]h ]h"]h$]h&]uh1jhj ubj)}(h,``field_range``: Match on a specific range. h]h)}(h+``field_range``: Match on a specific range.h](h)}(h``field_range``h]h field_range}(hjahhhNhNubah}(h]h ]h"]h$]h&]uh1hhj]ubh: Match on a specific range.}(hj]hhhNhNubeh}(h]h ]h"]h$]h&]uh1hhhhKhjYubah}(h]h ]h"]h$]h&]uh1jhj ubeh}(h]h ]h"]h$]h&]jcjduh1jhhhKhjubah}(h]h ]h"]h$]h&]uh1j hhhKhjhhubh)}(hThe id's of the header and the field should be specified in order to identify the specific field. Furthermore, the header index should be specified in order to distinguish multiple headers of the same type in a packet (tunneling).h]hThe id’s of the header and the field should be specified in order to identify the specific field. Furthermore, the header index should be specified in order to distinguish multiple headers of the same type in a packet (tunneling).}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhjhhubeh}(h]matchah ]h"]matchah$]h&]uh1hhjhhhhhK|ubh)}(hhh](h)}(hActionh]hAction}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjhhhhhKubh)}(h^Similar to match, the actions are kept primitive and close to hardware operation. For example:h]h^Similar to match, the actions are kept primitive and close to hardware operation. For example:}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhjhhubj )}(h* ``field_modify``: Modify the field value. * ``field_inc``: Increment the field value. * ``push_header``: Add a header. * ``pop_header``: Remove a header. h]j)}(hhh](j)}(h)``field_modify``: Modify the field value.h]h)}(hjh](h)}(h``field_modify``h]h field_modify}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjubh: Modify the field value.}(hjhhhNhNubeh}(h]h ]h"]h$]h&]uh1hhhhKhjubah}(h]h ]h"]h$]h&]uh1jhjubj)}(h)``field_inc``: Increment the field value.h]h)}(hjh](h)}(h ``field_inc``h]h field_inc}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjubh: Increment the field value.}(hjhhhNhNubeh}(h]h ]h"]h$]h&]uh1hhhhKhjubah}(h]h ]h"]h$]h&]uh1jhjubj)}(h``push_header``: Add a header.h]h)}(hjh](h)}(h``push_header``h]h push_header}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjubh: Add a header.}(hjhhhNhNubeh}(h]h ]h"]h$]h&]uh1hhhhKhjubah}(h]h ]h"]h$]h&]uh1jhjubj)}(h!``pop_header``: Remove a header. h]h)}(h ``pop_header``: Remove a header.h](h)}(h``pop_header``h]h pop_header}(hj>hhhNhNubah}(h]h ]h"]h$]h&]uh1hhj:ubh: Remove a header.}(hj:hhhNhNubeh}(h]h ]h"]h$]h&]uh1hhhhKhj6ubah}(h]h ]h"]h$]h&]uh1jhjubeh}(h]h ]h"]h$]h&]jcjduh1jhhhKhjubah}(h]h ]h"]h$]h&]uh1j hhhKhjhhubeh}(h]actionah ]h"]actionah$]h&]uh1hhjhhhhhKubh)}(hhh](h)}(hEntryh]hEntry}(hjshhhNhNubah}(h]h ]h"]h$]h&]uh1hhjphhhhhKubh)}(hXEntries of a specific table can be dumped on demand. Each eentry is identified with an index and its properties are described by a list of match/action values and specific counter. By dumping the tables content the interactions between tables can be resolved.h]hXEntries of a specific table can be dumped on demand. Each eentry is identified with an index and its properties are described by a list of match/action values and specific counter. By dumping the tables content the interactions between tables can be resolved.}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhjphhubeh}(h]entryah ]h"]entryah$]h&]uh1hhjhhhhhKubeh}(h]modelah ]h"]modelah$]h&]uh1hhhhhhhhKAubh)}(hhh](h)}(hAbstraction Exampleh]hAbstraction Example}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjhhhhhKubh)}(hXThe following is an example of the abstraction model of the L3 part of Mellanox Spectrum ASIC. The blocks are described in the order they appear in the pipeline. The table sizes in the following examples are not real hardware sizes and are provided for demonstration purposes.h]hXThe following is an example of the abstraction model of the L3 part of Mellanox Spectrum ASIC. The blocks are described in the order they appear in the pipeline. The table sizes in the following examples are not real hardware sizes and are provided for demonstration purposes.}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhjhhubh)}(hhh](h)}(hLPMh]hLPM}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjhhhhhKubh)}(hXThe LPM algorithm can be implemented as a list of hash tables. Each hash table contains routes with the same prefix length. The root of the list is /32, and in case of a miss the hardware will continue to the next hash table. The depth of the search will affect the data path latency.h]hXThe LPM algorithm can be implemented as a list of hash tables. Each hash table contains routes with the same prefix length. The root of the list is /32, and in case of a miss the hardware will continue to the next hash table. The depth of the search will affect the data path latency.}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhjhhubh)}(hX$In case of a hit the entry contains information about the next stage of the pipeline which resolves the MAC address. The next stage can be either local host table for directly connected routes, or adjacency table for next-hops. The ``meta.lpm_prefix`` field is used to connect two LPM tables.h](hIn case of a hit the entry contains information about the next stage of the pipeline which resolves the MAC address. The next stage can be either local host table for directly connected routes, or adjacency table for next-hops. The }(hjhhhNhNubh)}(h``meta.lpm_prefix``h]hmeta.lpm_prefix}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjubh) field is used to connect two LPM tables.}(hjhhhNhNubeh}(h]h ]h"]h$]h&]uh1hhhhKhjhhubh literal_block)}(hXYtable lpm_prefix_16 { size: 4096, counters_enabled: true, match: { meta.vr_id: exact, ipv4.dst_addr: exact_mask, ipv6.dst_addr: exact_mask, meta.lpm_prefix: exact }, action: { meta.adj_index: set, meta.adj_group_size: set, meta.rif_port: set, meta.lpm_prefix: set }, }h]hXYtable lpm_prefix_16 { size: 4096, counters_enabled: true, match: { meta.vr_id: exact, ipv4.dst_addr: exact_mask, ipv6.dst_addr: exact_mask, meta.lpm_prefix: exact }, action: { meta.adj_index: set, meta.adj_group_size: set, meta.rif_port: set, meta.lpm_prefix: set }, }}hjsbah}(h]h ]h"]h$]h&]forcehighlight_args}hhƌlanguagenoneuh1jhhhKhjhhubeh}(h]lpmah ]h"]lpmah$]h&]uh1hhjhhhhhKubh)}(hhh](h)}(h Local Hosth]h Local Host}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjhhhhhKubh)}(hXIn the case of local routes the LPM lookup already resolves the egress router interface (RIF), yet the exact MAC address is not known. The local host table is a hash table combining the output interface id with destination IP address as a key. The result is the MAC address.h]hXIn the case of local routes the LPM lookup already resolves the egress router interface (RIF), yet the exact MAC address is not known. The local host table is a hash table combining the output interface id with destination IP address as a key. The result is the MAC address.}(hj+hhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhjhhubj)}(htable local_host { size: 4096, counters_enabled: true, match: { meta.rif_port: exact, ipv4.dst_addr: exact}, action: { ethernet.daddr: set } }h]htable local_host { size: 4096, counters_enabled: true, match: { meta.rif_port: exact, ipv4.dst_addr: exact}, action: { ethernet.daddr: set } }}hj9sbah}(h]h ]h"]h$]h&]forcehighlight_args}hhjjuh1jhhhKhjhhubeh}(h] local-hostah ]h"] local hostah$]h&]uh1hhjhhhhhKubh)}(hhh](h)}(h Adjacencyh]h Adjacency}(hjUhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjRhhhhhKubh)}(hXRIn case of remote routes this table does the ECMP. The LPM lookup results in ECMP group size and index that serves as a global offset into this table. Concurrently a hash of the packet is generated. Based on the ECMP group size and the packet's hash a local offset is generated. Multiple LPM entries can point to the same adjacency group.h]hXTIn case of remote routes this table does the ECMP. The LPM lookup results in ECMP group size and index that serves as a global offset into this table. Concurrently a hash of the packet is generated. Based on the ECMP group size and the packet’s hash a local offset is generated. Multiple LPM entries can point to the same adjacency group.}(hjchhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhjRhhubj)}(htable adjacency { size: 4096, counters_enabled: true, match: { meta.adj_index: exact, meta.adj_group_size: exact, meta.packet_hash_index: exact }, action: { ethernet.daddr: set, meta.erif: set } }h]htable adjacency { size: 4096, counters_enabled: true, match: { meta.adj_index: exact, meta.adj_group_size: exact, meta.packet_hash_index: exact }, action: { ethernet.daddr: set, meta.erif: set } }}hjqsbah}(h]h ]h"]h$]h&]forcehighlight_args}hhjjuh1jhhhKhjRhhubeh}(h] adjacencyah ]h"] adjacencyah$]h&]uh1hhjhhhhhKubh)}(hhh](h)}(hERIFh]hERIF}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhjhhhhhKubh)}(hX#In case the egress RIF and destination MAC have been resolved by previous tables this table does multiple operations like TTL decrease and MTU check. Then the decision of forward/drop is taken and the port L3 statistics are updated based on the packet's type (broadcast, unicast, multicast).h]hX%In case the egress RIF and destination MAC have been resolved by previous tables this table does multiple operations like TTL decrease and MTU check. Then the decision of forward/drop is taken and the port L3 statistics are updated based on the packet’s type (broadcast, unicast, multicast).}(hjhhhNhNubah}(h]h ]h"]h$]h&]uh1hhhhKhjhhubj)}(hXtable erif { size: 800, counters_enabled: true, match: { meta.rif_port: exact, meta.is_l3_unicast: exact, meta.is_l3_broadcast: exact, meta.is_l3_multicast, exact }, action: { meta.l3_drop: set, meta.l3_forward: set } }h]hXtable erif { size: 800, counters_enabled: true, match: { meta.rif_port: exact, meta.is_l3_unicast: exact, meta.is_l3_broadcast: exact, meta.is_l3_multicast, exact }, action: { meta.l3_drop: set, meta.l3_forward: set } }}hjsbah}(h]h ]h"]h$]h&]forcehighlight_args}hhjjuh1jhhhKhjhhubeh}(h]erifah ]h"]erifah$]h&]uh1hhjhhhhhKubeh}(h]abstraction-exampleah ]h"]abstraction exampleah$]h&]uh1hhhhhhhhKubeh}(h] devlink-dpipeah ]h"] devlink dpipeah$]h&]uh1hhhhhhhhKubeh}(h]h ]h"]h$]h&]sourcehuh1hcurrent_sourceN current_lineNsettingsdocutils.frontendValues)}(hN generatorN datestampN source_linkN source_urlN toc_backlinksentryfootnote_backlinksK sectnum_xformKstrip_commentsNstrip_elements_with_classesN strip_classesN report_levelK halt_levelKexit_status_levelKdebugNwarning_streamN tracebackinput_encoding utf-8-siginput_encoding_error_handlerstrictoutput_encodingutf-8output_encoding_error_handlerjerror_encodingutf-8error_encoding_error_handlerbackslashreplace language_codeenrecord_dependenciesNconfigN id_prefixhauto_id_prefixid dump_settingsNdump_internalsNdump_transformsNdump_pseudo_xmlNexpose_internalsNstrict_visitorN_disable_configN_sourcehnj _destinationN _config_files]7/var/lib/git/docbuild/linux/Documentation/docutils.confafile_insertion_enabled raw_enabledKline_length_limitM'pep_referencesN pep_base_urlhttps://peps.python.org/pep_file_url_templatepep-%04drfc_referencesN rfc_base_url&https://datatracker.ietf.org/doc/html/ tab_widthKtrim_footnote_reference_spacesyntax_highlightlong smart_quotessmartquotes_locales]character_level_inline_markupdoctitle_xform docinfo_xformKsectsubtitle_xform image_loadinglinkembed_stylesheetcloak_email_addressessection_self_linkenvNubreporterNindirect_targets]substitution_defs}substitution_names}refnames}refids}nameids}(jjj]jZjjjjjjjjjjjmjjjjjjjjjOjLjjjju nametypes}(jj]jjjjjjmjjjjOjjuh}(jhjZhjj`jjjjjjjjjjjjjpjjjjjLjjjRjju footnote_refs} citation_refs} autofootnotes]autofootnote_refs]symbol_footnotes]symbol_footnote_refs] footnotes] citations]autofootnote_startKsymbol_footnote_startK id_counter collectionsCounter}Rparse_messages]transform_messages] transformerN include_log] decorationNhhub.