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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
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Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
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+.. SPDX-License-Identifier: GPL-2.0
+
+=============
+Devlink DPIPE
+=============
+
+Background
+==========
+
+While 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.
+
+For 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.
+
+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.
+
+This 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.
+
+One 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.
+
+In 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.
+
+Overview
+========
+
+The ``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.
+
+Traditionally 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.
+
+For 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.
+
+Model
+=====
+
+The ``DPIPE`` model introduces several objects:
+
+ * headers
+ * tables
+ * entries
+
+A ``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.
+
+The hardware pipeline is not port specific, but rather describes the whole
+ASIC. Thus it is tied to the top of the ``devlink`` infrastructure.
+
+Drivers 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.
+
+``devlink-dpipe`` generally is not intended for configuration. The exception
+is hardware counting for a specific table.
+
+The following commands are used to obtain the ``dpipe`` objects from
+userspace:
+
+ * ``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.
+
+Table
+-----
+
+The driver should implement the following operations for each table:
+
+ * ``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.
+
+Header/Field
+------------
+
+In 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.
+
+In 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.
+
+Match
+-----
+
+Matches 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:
+
+ * ``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.
+
+The 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).
+
+Action
+------
+
+Similar to match, the actions are kept primitive and close to hardware
+operation. For example:
+
+ * ``field_modify``: Modify the field value.
+ * ``field_inc``: Increment the field value.
+ * ``push_header``: Add a header.
+ * ``pop_header``: Remove a header.
+
+Entry
+-----
+
+Entries 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.
+
+Abstraction Example
+===================
+
+The 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.
+
+LPM
+---
+
+The 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.
+
+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.
+
+.. code::
+
+ table 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 },
+ }
+
+Local Host
+----------
+
+In 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.
+
+.. code::
+
+ table local_host {
+ size: 4096,
+ counters_enabled: true,
+ match: { meta.rif_port: exact,
+ ipv4.dst_addr: exact},
+ action: { ethernet.daddr: set }
+ }
+
+Adjacency
+---------
+
+In 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.
+
+.. code::
+
+ table 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 }
+ }
+
+ERIF
+----
+
+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).
+
+.. code::
+
+ table 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 }
+ }