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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
+
+======================================
+CoreSight System Configuration Manager
+======================================
+
+ :Author: Mike Leach <mike.leach@linaro.org>
+ :Date: October 2020
+
+Introduction
+============
+
+The CoreSight System Configuration manager is an API that allows the
+programming of the CoreSight system with pre-defined configurations that
+can then be easily enabled from sysfs or perf.
+
+Many CoreSight components can be programmed in complex ways - especially ETMs.
+In addition, components can interact across the CoreSight system, often via
+the cross trigger components such as CTI and CTM. These system settings can
+be defined and enabled as named configurations.
+
+
+Basic Concepts
+==============
+
+This section introduces the basic concepts of a CoreSight system configuration.
+
+
+Features
+--------
+
+A feature is a named set of programming for a CoreSight device. The programming
+is device dependent, and can be defined in terms of absolute register values,
+resource usage and parameter values.
+
+The feature is defined using a descriptor. This descriptor is used to load onto
+a matching device, either when the feature is loaded into the system, or when the
+CoreSight device is registered with the configuration manager.
+
+The load process involves interpreting the descriptor into a set of register
+accesses in the driver - the resource usage and parameter descriptions
+translated into appropriate register accesses. This interpretation makes it easy
+and efficient for the feature to be programmed onto the device when required.
+
+The feature will not be active on the device until the feature is enabled, and
+the device itself is enabled. When the device is enabled then enabled features
+will be programmed into the device hardware.
+
+A feature is enabled as part of a configuration being enabled on the system.
+
+
+Parameter Value
+~~~~~~~~~~~~~~~
+
+A parameter value is a named value that may be set by the user prior to the
+feature being enabled that can adjust the behaviour of the operation programmed
+by the feature.
+
+For example, this could be a count value in a programmed operation that repeats
+at a given rate. When the feature is enabled then the current value of the
+parameter is used in programming the device.
+
+The feature descriptor defines a default value for a parameter, which is used
+if the user does not supply a new value.
+
+Users can update parameter values using the configfs API for the CoreSight
+system - which is described below.
+
+The current value of the parameter is loaded into the device when the feature
+is enabled on that device.
+
+
+Configurations
+--------------
+
+A configuration defines a set of features that are to be used in a trace
+session where the configuration is selected. For any trace session only one
+configuration may be selected.
+
+The features defined may be on any type of device that is registered
+to support system configuration. A configuration may select features to be
+enabled on a class of devices - i.e. any ETMv4, or specific devices, e.g. a
+specific CTI on the system.
+
+As with the feature, a descriptor is used to define the configuration.
+This will define the features that must be enabled as part of the configuration
+as well as any preset values that can be used to override default parameter
+values.
+
+
+Preset Values
+~~~~~~~~~~~~~
+
+Preset values are easily selectable sets of parameter values for the features
+that the configuration uses. The number of values in a single preset set, equals
+the sum of parameter values in the features used by the configuration.
+
+e.g. a configuration consists of 3 features, one has 2 parameters, one has
+a single parameter, and another has no parameters. A single preset set will
+therefore have 3 values.
+
+Presets are optionally defined by the configuration, up to 15 can be defined.
+If no preset is selected, then the parameter values defined in the feature
+are used as normal.
+
+
+Operation
+~~~~~~~~~
+
+The following steps take place in the operation of a configuration.
+
+1) In this example, the configuration is 'autofdo', which has an
+ associated feature 'strobing' that works on ETMv4 CoreSight Devices.
+
+2) The configuration is enabled. For example 'perf' may select the
+ configuration as part of its command line::
+
+ perf record -e cs_etm/autofdo/ myapp
+
+ which will enable the 'autofdo' configuration.
+
+3) perf starts tracing on the system. As each ETMv4 that perf uses for
+ trace is enabled, the configuration manager will check if the ETMv4
+ has a feature that relates to the currently active configuration.
+ In this case 'strobing' is enabled & programmed into the ETMv4.
+
+4) When the ETMv4 is disabled, any registers marked as needing to be
+ saved will be read back.
+
+5) At the end of the perf session, the configuration will be disabled.
+
+
+Viewing Configurations and Features
+===================================
+
+The set of configurations and features that are currently loaded into the
+system can be viewed using the configfs API.
+
+Mount configfs as normal and the 'cs-syscfg' subsystem will appear::
+
+ $ ls /config
+ cs-syscfg stp-policy
+
+This has two sub-directories::
+
+ $ cd cs-syscfg/
+ $ ls
+ configurations features
+
+The system has the configuration 'autofdo' built in. It may be examined as
+follows::
+
+ $ cd configurations/
+ $ ls
+ autofdo
+ $ cd autofdo/
+ $ ls
+ description feature_refs preset1 preset3 preset5 preset7 preset9
+ enable preset preset2 preset4 preset6 preset8
+ $ cat description
+ Setup ETMs with strobing for autofdo
+ $ cat feature_refs
+ strobing
+
+Each preset declared has a 'preset<n>' subdirectory declared. The values for
+the preset can be examined::
+
+ $ cat preset1/values
+ strobing.window = 0x1388 strobing.period = 0x2
+ $ cat preset2/values
+ strobing.window = 0x1388 strobing.period = 0x4
+
+The 'enable' and 'preset' files allow the control of a configuration when
+using CoreSight with sysfs.
+
+The features referenced by the configuration can be examined in the features
+directory::
+
+ $ cd ../../features/strobing/
+ $ ls
+ description matches nr_params params
+ $ cat description
+ Generate periodic trace capture windows.
+ parameter 'window': a number of CPU cycles (W)
+ parameter 'period': trace enabled for W cycles every period x W cycles
+ $ cat matches
+ SRC_ETMV4
+ $ cat nr_params
+ 2
+
+Move to the params directory to examine and adjust parameters::
+
+ cd params
+ $ ls
+ period window
+ $ cd period
+ $ ls
+ value
+ $ cat value
+ 0x2710
+ # echo 15000 > value
+ # cat value
+ 0x3a98
+
+Parameters adjusted in this way are reflected in all device instances that have
+loaded the feature.
+
+
+Using Configurations in perf
+============================
+
+The configurations loaded into the CoreSight configuration management are
+also declared in the perf 'cs_etm' event infrastructure so that they can
+be selected when running trace under perf::
+
+ $ ls /sys/devices/cs_etm
+ cpu0 cpu2 events nr_addr_filters power subsystem uevent
+ cpu1 cpu3 format perf_event_mux_interval_ms sinks type
+
+The key directory here is 'events' - a generic perf directory which allows
+selection on the perf command line. As with the sinks entries, this provides
+a hash of the configuration name.
+
+The entry in the 'events' directory uses perfs built in syntax generator
+to substitute the syntax for the name when evaluating the command::
+
+ $ ls events/
+ autofdo
+ $ cat events/autofdo
+ configid=0xa7c3dddd
+
+The 'autofdo' configuration may be selected on the perf command line::
+
+ $ perf record -e cs_etm/autofdo/u --per-thread <application>
+
+A preset to override the current parameter values can also be selected::
+
+ $ perf record -e cs_etm/autofdo,preset=1/u --per-thread <application>
+
+When configurations are selected in this way, then the trace sink used is
+automatically selected.
+
+Using Configurations in sysfs
+=============================
+
+Coresight can be controlled using sysfs. When this is in use then a configuration
+can be made active for the devices that are used in the sysfs session.
+
+In a configuration there are 'enable' and 'preset' files.
+
+To enable a configuration for use with sysfs::
+
+ $ cd configurations/autofdo
+ $ echo 1 > enable
+
+This will then use any default parameter values in the features - which can be
+adjusted as described above.
+
+To use a preset<n> set of parameter values::
+
+ $ echo 3 > preset
+
+This will select preset3 for the configuration.
+The valid values for preset are 0 - to deselect presets, and any value of
+<n> where a preset<n> sub-directory is present.
+
+Note that the active sysfs configuration is a global parameter, therefore
+only a single configuration can be active for sysfs at any one time.
+Attempting to enable a second configuration will result in an error.
+Additionally, attempting to disable the configuration while in use will
+also result in an error.
+
+The use of the active configuration by sysfs is independent of the configuration
+used in perf.
+
+
+Creating and Loading Custom Configurations
+==========================================
+
+Custom configurations and / or features can be dynamically loaded into the
+system by using a loadable module.
+
+An example of a custom configuration is found in ./samples/coresight.
+
+This creates a new configuration that uses the existing built in
+strobing feature, but provides a different set of presets.
+
+When the module is loaded, then the configuration appears in the configfs
+file system and is selectable in the same way as the built in configuration
+described above.
+
+Configurations can use previously loaded features. The system will ensure
+that it is not possible to unload a feature that is currently in use, by
+enforcing the unload order as the strict reverse of the load order.