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authorLinus Torvalds <torvalds@linux-foundation.org>2022-10-04 13:38:03 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2022-10-04 13:38:03 -0700
commit0326074ff4652329f2a1a9c8685104576bd8d131 (patch)
tree9a7574c7ccb05bf4c7cb34fc5a65457bb8f495cb /Documentation/networking/dsa/configuration.rst
parent522667b24f08009591c90e75bfe2ffb67f555498 (diff)
parent681bf011b9b5989c6e9db6beb64494918aab9a43 (diff)
downloadlinux-0326074ff4652329f2a1a9c8685104576bd8d131.tar.gz
Merge tag 'net-next-6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from Jakub Kicinski: "Core: - Introduce and use a single page frag cache for allocating small skb heads, clawing back the 10-20% performance regression in UDP flood test from previous fixes. - Run packets which already went thru HW coalescing thru SW GRO. This significantly improves TCP segment coalescing and simplifies deployments as different workloads benefit from HW or SW GRO. - Shrink the size of the base zero-copy send structure. - Move TCP init under a new slow / sleepable version of DO_ONCE(). BPF: - Add BPF-specific, any-context-safe memory allocator. - Add helpers/kfuncs for PKCS#7 signature verification from BPF programs. - Define a new map type and related helpers for user space -> kernel communication over a ring buffer (BPF_MAP_TYPE_USER_RINGBUF). - Allow targeting BPF iterators to loop through resources of one task/thread. - Add ability to call selected destructive functions. Expose crash_kexec() to allow BPF to trigger a kernel dump. Use CAP_SYS_BOOT check on the loading process to judge permissions. - Enable BPF to collect custom hierarchical cgroup stats efficiently by integrating with the rstat framework. - Support struct arguments for trampoline based programs. Only structs with size <= 16B and x86 are supported. - Invoke cgroup/connect{4,6} programs for unprivileged ICMP ping sockets (instead of just TCP and UDP sockets). - Add a helper for accessing CLOCK_TAI for time sensitive network related programs. - Support accessing network tunnel metadata's flags. - Make TCP SYN ACK RTO tunable by BPF programs with TCP Fast Open. - Add support for writing to Netfilter's nf_conn:mark. Protocols: - WiFi: more Extremely High Throughput (EHT) and Multi-Link Operation (MLO) work (802.11be, WiFi 7). - vsock: improve support for SO_RCVLOWAT. - SMC: support SO_REUSEPORT. - Netlink: define and document how to use netlink in a "modern" way. Support reporting missing attributes via extended ACK. - IPSec: support collect metadata mode for xfrm interfaces. - TCPv6: send consistent autoflowlabel in SYN_RECV state and RST packets. - TCP: introduce optional per-netns connection hash table to allow better isolation between namespaces (opt-in, at the cost of memory and cache pressure). - MPTCP: support TCP_FASTOPEN_CONNECT. - Add NEXT-C-SID support in Segment Routing (SRv6) End behavior. - Adjust IP_UNICAST_IF sockopt behavior for connected UDP sockets. - Open vSwitch: - Allow specifying ifindex of new interfaces. - Allow conntrack and metering in non-initial user namespace. - TLS: support the Korean ARIA-GCM crypto algorithm. - Remove DECnet support. Driver API: - Allow selecting the conduit interface used by each port in DSA switches, at runtime. - Ethernet Power Sourcing Equipment and Power Device support. - Add tc-taprio support for queueMaxSDU parameter, i.e. setting per traffic class max frame size for time-based packet schedules. - Support PHY rate matching - adapting between differing host-side and link-side speeds. - Introduce QUSGMII PHY mode and 1000BASE-KX interface mode. - Validate OF (device tree) nodes for DSA shared ports; make phylink-related properties mandatory on DSA and CPU ports. Enforcing more uniformity should allow transitioning to phylink. - Require that flash component name used during update matches one of the components for which version is reported by info_get(). - Remove "weight" argument from driver-facing NAPI API as much as possible. It's one of those magic knobs which seemed like a good idea at the time but is too indirect to use in practice. - Support offload of TLS connections with 256 bit keys. New hardware / drivers: - Ethernet: - Microchip KSZ9896 6-port Gigabit Ethernet Switch - Renesas Ethernet AVB (EtherAVB-IF) Gen4 SoCs - Analog Devices ADIN1110 and ADIN2111 industrial single pair Ethernet (10BASE-T1L) MAC+PHY. - Rockchip RV1126 Gigabit Ethernet (a version of stmmac IP). - Ethernet SFPs / modules: - RollBall / Hilink / Turris 10G copper SFPs - HALNy GPON module - WiFi: - CYW43439 SDIO chipset (brcmfmac) - CYW89459 PCIe chipset (brcmfmac) - BCM4378 on Apple platforms (brcmfmac) Drivers: - CAN: - gs_usb: HW timestamp support - Ethernet PHYs: - lan8814: cable diagnostics - Ethernet NICs: - Intel (100G): - implement control of FCS/CRC stripping - port splitting via devlink - L2TPv3 filtering offload - nVidia/Mellanox: - tunnel offload for sub-functions - MACSec offload, w/ Extended packet number and replay window offload - significantly restructure, and optimize the AF_XDP support, align the behavior with other vendors - Huawei: - configuring DSCP map for traffic class selection - querying standard FEC statistics - querying SerDes lane number via ethtool - Marvell/Cavium: - egress priority flow control - MACSec offload - AMD/SolarFlare: - PTP over IPv6 and raw Ethernet - small / embedded: - ax88772: convert to phylink (to support SFP cages) - altera: tse: convert to phylink - ftgmac100: support fixed link - enetc: standard Ethtool counters - macb: ZynqMP SGMII dynamic configuration support - tsnep: support multi-queue and use page pool - lan743x: Rx IP & TCP checksum offload - igc: add xdp frags support to ndo_xdp_xmit - Ethernet high-speed switches: - Marvell (prestera): - support SPAN port features (traffic mirroring) - nexthop object offloading - Microchip (sparx5): - multicast forwarding offload - QoS queuing offload (tc-mqprio, tc-tbf, tc-ets) - Ethernet embedded switches: - Marvell (mv88e6xxx): - support RGMII cmode - NXP (felix): - standardized ethtool counters - Microchip (lan966x): - QoS queuing offload (tc-mqprio, tc-tbf, tc-cbs, tc-ets) - traffic policing and mirroring - link aggregation / bonding offload - QUSGMII PHY mode support - Qualcomm 802.11ax WiFi (ath11k): - cold boot calibration support on WCN6750 - support to connect to a non-transmit MBSSID AP profile - enable remain-on-channel support on WCN6750 - Wake-on-WLAN support for WCN6750 - support to provide transmit power from firmware via nl80211 - support to get power save duration for each client - spectral scan support for 160 MHz - MediaTek WiFi (mt76): - WiFi-to-Ethernet bridging offload for MT7986 chips - RealTek WiFi (rtw89): - P2P support" * tag 'net-next-6.1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1864 commits) eth: pse: add missing static inlines once: rename _SLOW to _SLEEPABLE net: pse-pd: add regulator based PSE driver dt-bindings: net: pse-dt: add bindings for regulator based PoDL PSE controller ethtool: add interface to interact with Ethernet Power Equipment net: mdiobus: search for PSE nodes by parsing PHY nodes. net: mdiobus: fwnode_mdiobus_register_phy() rework error handling net: add framework to support Ethernet PSE and PDs devices dt-bindings: net: phy: add PoDL PSE property net: marvell: prestera: Propagate nh state from hw to kernel net: marvell: prestera: Add neighbour cache accounting net: marvell: prestera: add stub handler neighbour events net: marvell: prestera: Add heplers to interact with fib_notifier_info net: marvell: prestera: Add length macros for prestera_ip_addr net: marvell: prestera: add delayed wq and flush wq on deinit net: marvell: prestera: Add strict cleanup of fib arbiter net: marvell: prestera: Add cleanup of allocated fib_nodes net: marvell: prestera: Add router nexthops ABI eth: octeon: fix build after netif_napi_add() changes net/mlx5: E-Switch, Return EBUSY if can't get mode lock ...
Diffstat (limited to 'Documentation/networking/dsa/configuration.rst')
-rw-r--r--Documentation/networking/dsa/configuration.rst96
1 files changed, 96 insertions, 0 deletions
diff --git a/Documentation/networking/dsa/configuration.rst b/Documentation/networking/dsa/configuration.rst
index 2b08f1a772d3..827701f8cbfe 100644
--- a/Documentation/networking/dsa/configuration.rst
+++ b/Documentation/networking/dsa/configuration.rst
@@ -49,6 +49,9 @@ In this documentation the following Ethernet interfaces are used:
*eth0*
the master interface
+*eth1*
+ another master interface
+
*lan1*
a slave interface
@@ -360,3 +363,96 @@ the ``self`` flag) has been removed. This results in the following changes:
Script writers are therefore encouraged to use the ``master static`` set of
flags when working with bridge FDB entries on DSA switch interfaces.
+
+Affinity of user ports to CPU ports
+-----------------------------------
+
+Typically, DSA switches are attached to the host via a single Ethernet
+interface, but in cases where the switch chip is discrete, the hardware design
+may permit the use of 2 or more ports connected to the host, for an increase in
+termination throughput.
+
+DSA can make use of multiple CPU ports in two ways. First, it is possible to
+statically assign the termination traffic associated with a certain user port
+to be processed by a certain CPU port. This way, user space can implement
+custom policies of static load balancing between user ports, by spreading the
+affinities according to the available CPU ports.
+
+Secondly, it is possible to perform load balancing between CPU ports on a per
+packet basis, rather than statically assigning user ports to CPU ports.
+This can be achieved by placing the DSA masters under a LAG interface (bonding
+or team). DSA monitors this operation and creates a mirror of this software LAG
+on the CPU ports facing the physical DSA masters that constitute the LAG slave
+devices.
+
+To make use of multiple CPU ports, the firmware (device tree) description of
+the switch must mark all the links between CPU ports and their DSA masters
+using the ``ethernet`` reference/phandle. At startup, only a single CPU port
+and DSA master will be used - the numerically first port from the firmware
+description which has an ``ethernet`` property. It is up to the user to
+configure the system for the switch to use other masters.
+
+DSA uses the ``rtnl_link_ops`` mechanism (with a "dsa" ``kind``) to allow
+changing the DSA master of a user port. The ``IFLA_DSA_MASTER`` u32 netlink
+attribute contains the ifindex of the master device that handles each slave
+device. The DSA master must be a valid candidate based on firmware node
+information, or a LAG interface which contains only slaves which are valid
+candidates.
+
+Using iproute2, the following manipulations are possible:
+
+ .. code-block:: sh
+
+ # See the DSA master in current use
+ ip -d link show dev swp0
+ (...)
+ dsa master eth0
+
+ # Static CPU port distribution
+ ip link set swp0 type dsa master eth1
+ ip link set swp1 type dsa master eth0
+ ip link set swp2 type dsa master eth1
+ ip link set swp3 type dsa master eth0
+
+ # CPU ports in LAG, using explicit assignment of the DSA master
+ ip link add bond0 type bond mode balance-xor && ip link set bond0 up
+ ip link set eth1 down && ip link set eth1 master bond0
+ ip link set swp0 type dsa master bond0
+ ip link set swp1 type dsa master bond0
+ ip link set swp2 type dsa master bond0
+ ip link set swp3 type dsa master bond0
+ ip link set eth0 down && ip link set eth0 master bond0
+ ip -d link show dev swp0
+ (...)
+ dsa master bond0
+
+ # CPU ports in LAG, relying on implicit migration of the DSA master
+ ip link add bond0 type bond mode balance-xor && ip link set bond0 up
+ ip link set eth0 down && ip link set eth0 master bond0
+ ip link set eth1 down && ip link set eth1 master bond0
+ ip -d link show dev swp0
+ (...)
+ dsa master bond0
+
+Notice that in the case of CPU ports under a LAG, the use of the
+``IFLA_DSA_MASTER`` netlink attribute is not strictly needed, but rather, DSA
+reacts to the ``IFLA_MASTER`` attribute change of its present master (``eth0``)
+and migrates all user ports to the new upper of ``eth0``, ``bond0``. Similarly,
+when ``bond0`` is destroyed using ``RTM_DELLINK``, DSA migrates the user ports
+that were assigned to this interface to the first physical DSA master which is
+eligible, based on the firmware description (it effectively reverts to the
+startup configuration).
+
+In a setup with more than 2 physical CPU ports, it is therefore possible to mix
+static user to CPU port assignment with LAG between DSA masters. It is not
+possible to statically assign a user port towards a DSA master that has any
+upper interfaces (this includes LAG devices - the master must always be the LAG
+in this case).
+
+Live changing of the DSA master (and thus CPU port) affinity of a user port is
+permitted, in order to allow dynamic redistribution in response to traffic.
+
+Physical DSA masters are allowed to join and leave at any time a LAG interface
+used as a DSA master; however, DSA will reject a LAG interface as a valid
+candidate for being a DSA master unless it has at least one physical DSA master
+as a slave device.