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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
+
+======================================
+HiSilicon PCIe Tune and Trace device
+======================================
+
+Introduction
+============
+
+HiSilicon PCIe tune and trace device (PTT) is a PCIe Root Complex
+integrated Endpoint (RCiEP) device, providing the capability
+to dynamically monitor and tune the PCIe link's events (tune),
+and trace the TLP headers (trace). The two functions are independent,
+but is recommended to use them together to analyze and enhance the
+PCIe link's performance.
+
+On Kunpeng 930 SoC, the PCIe Root Complex is composed of several
+PCIe cores. Each PCIe core includes several Root Ports and a PTT
+RCiEP, like below. The PTT device is capable of tuning and
+tracing the links of the PCIe core.
+::
+
+ +--------------Core 0-------+
+ | | [ PTT ] |
+ | | [Root Port]---[Endpoint]
+ | | [Root Port]---[Endpoint]
+ | | [Root Port]---[Endpoint]
+ Root Complex |------Core 1-------+
+ | | [ PTT ] |
+ | | [Root Port]---[ Switch ]---[Endpoint]
+ | | [Root Port]---[Endpoint] `-[Endpoint]
+ | | [Root Port]---[Endpoint]
+ +---------------------------+
+
+The PTT device driver registers one PMU device for each PTT device.
+The name of each PTT device is composed of 'hisi_ptt' prefix with
+the id of the SICL and the Core where it locates. The Kunpeng 930
+SoC encapsulates multiple CPU dies (SCCL, Super CPU Cluster) and
+IO dies (SICL, Super I/O Cluster), where there's one PCIe Root
+Complex for each SICL.
+::
+
+ /sys/devices/hisi_ptt<sicl_id>_<core_id>
+
+Tune
+====
+
+PTT tune is designed for monitoring and adjusting PCIe link parameters (events).
+Currently we support events in 2 classes. The scope of the events
+covers the PCIe core to which the PTT device belongs.
+
+Each event is presented as a file under $(PTT PMU dir)/tune, and
+a simple open/read/write/close cycle will be used to tune the event.
+::
+
+ $ cd /sys/devices/hisi_ptt<sicl_id>_<core_id>/tune
+ $ ls
+ qos_tx_cpl qos_tx_np qos_tx_p
+ tx_path_rx_req_alloc_buf_level
+ tx_path_tx_req_alloc_buf_level
+ $ cat qos_tx_dp
+ 1
+ $ echo 2 > qos_tx_dp
+ $ cat qos_tx_dp
+ 2
+
+Current value (numerical value) of the event can be simply read
+from the file, and the desired value written to the file to tune.
+
+1. Tx Path QoS Control
+------------------------
+
+The following files are provided to tune the QoS of the tx path of
+the PCIe core.
+
+- qos_tx_cpl: weight of Tx completion TLPs
+- qos_tx_np: weight of Tx non-posted TLPs
+- qos_tx_p: weight of Tx posted TLPs
+
+The weight influences the proportion of certain packets on the PCIe link.
+For example, for the storage scenario, increase the proportion
+of the completion packets on the link to enhance the performance as
+more completions are consumed.
+
+The available tune data of these events is [0, 1, 2].
+Writing a negative value will return an error, and out of range
+values will be converted to 2. Note that the event value just
+indicates a probable level, but is not precise.
+
+2. Tx Path Buffer Control
+-------------------------
+
+Following files are provided to tune the buffer of tx path of the PCIe core.
+
+- rx_alloc_buf_level: watermark of Rx requested
+- tx_alloc_buf_level: watermark of Tx requested
+
+These events influence the watermark of the buffer allocated for each
+type. Rx means the inbound while Tx means outbound. The packets will
+be stored in the buffer first and then transmitted either when the
+watermark reached or when timed out. For a busy direction, you should
+increase the related buffer watermark to avoid frequently posting and
+thus enhance the performance. In most cases just keep the default value.
+
+The available tune data of above events is [0, 1, 2].
+Writing a negative value will return an error, and out of range
+values will be converted to 2. Note that the event value just
+indicates a probable level, but is not precise.
+
+Trace
+=====
+
+PTT trace is designed for dumping the TLP headers to the memory, which
+can be used to analyze the transactions and usage condition of the PCIe
+Link. You can choose to filter the traced headers by either Requester ID,
+or those downstream of a set of Root Ports on the same core of the PTT
+device. It's also supported to trace the headers of certain type and of
+certain direction.
+
+You can use the perf command `perf record` to set the parameters, start
+trace and get the data. It's also supported to decode the trace
+data with `perf report`. The control parameters for trace is inputted
+as event code for each events, which will be further illustrated later.
+An example usage is like
+::
+
+ $ perf record -e hisi_ptt0_2/filter=0x80001,type=1,direction=1,
+ format=1/ -- sleep 5
+
+This will trace the TLP headers downstream root port 0000:00:10.1 (event
+code for event 'filter' is 0x80001) with type of posted TLP requests,
+direction of inbound and traced data format of 8DW.
+
+1. Filter
+---------
+
+The TLP headers to trace can be filtered by the Root Ports or the Requester ID
+of the Endpoint, which are located on the same core of the PTT device. You can
+set the filter by specifying the `filter` parameter which is required to start
+the trace. The parameter value is 20 bit. Bit 19 indicates the filter type.
+1 for Root Port filter and 0 for Requester filter. Bit[15:0] indicates the
+filter value. The value for a Root Port is a mask of the core port id which is
+calculated from its PCI Slot ID as (slotid & 7) * 2. The value for a Requester
+is the Requester ID (Device ID of the PCIe function). Bit[18:16] is currently
+reserved for extension.
+
+For example, if the desired filter is Endpoint function 0000:01:00.1 the filter
+value will be 0x00101. If the desired filter is Root Port 0000:00:10.0 then
+then filter value is calculated as 0x80001.
+
+Note that multiple Root Ports can be specified at one time, but only one
+Endpoint function can be specified in one trace. Specifying both Root Port
+and function at the same time is not supported. Driver maintains a list of
+available filters and will check the invalid inputs.
+
+Currently the available filters are detected in driver's probe. If the supported
+devices are removed/added after probe, you may need to reload the driver to update
+the filters.
+
+2. Type
+-------
+
+You can trace the TLP headers of certain types by specifying the `type`
+parameter, which is required to start the trace. The parameter value is
+8 bit. Current supported types and related values are shown below:
+
+- 8'b00000001: posted requests (P)
+- 8'b00000010: non-posted requests (NP)
+- 8'b00000100: completions (CPL)
+
+You can specify multiple types when tracing inbound TLP headers, but can only
+specify one when tracing outbound TLP headers.
+
+3. Direction
+------------
+
+You can trace the TLP headers from certain direction, which is relative
+to the Root Port or the PCIe core, by specifying the `direction` parameter.
+This is optional and the default parameter is inbound. The parameter value
+is 4 bit. When the desired format is 4DW, directions and related values
+supported are shown below:
+
+- 4'b0000: inbound TLPs (P, NP, CPL)
+- 4'b0001: outbound TLPs (P, NP, CPL)
+- 4'b0010: outbound TLPs (P, NP, CPL) and inbound TLPs (P, NP, CPL B)
+- 4'b0011: outbound TLPs (P, NP, CPL) and inbound TLPs (CPL A)
+
+When the desired format is 8DW, directions and related values supported are
+shown below:
+
+- 4'b0000: reserved
+- 4'b0001: outbound TLPs (P, NP, CPL)
+- 4'b0010: inbound TLPs (P, NP, CPL B)
+- 4'b0011: inbound TLPs (CPL A)
+
+Inbound completions are classified into two types:
+
+- completion A (CPL A): completion of CHI/DMA/Native non-posted requests, except for CPL B
+- completion B (CPL B): completion of DMA remote2local and P2P non-posted requests
+
+4. Format
+--------------
+
+You can change the format of the traced TLP headers by specifying the
+`format` parameter. The default format is 4DW. The parameter value is 4 bit.
+Current supported formats and related values are shown below:
+
+- 4'b0000: 4DW length per TLP header
+- 4'b0001: 8DW length per TLP header
+
+The traced TLP header format is different from the PCIe standard.
+
+When using the 8DW data format, the entire TLP header is logged
+(Header DW0-3 shown below). For example, the TLP header for Memory
+Reads with 64-bit addresses is shown in PCIe r5.0, Figure 2-17;
+the header for Configuration Requests is shown in Figure 2.20, etc.
+
+In addition, 8DW trace buffer entries contain a timestamp and
+possibly a prefix for a PASID TLP prefix (see Figure 6-20, PCIe r5.0).
+Otherwise this field will be all 0.
+
+The bit[31:11] of DW0 is always 0x1fffff, which can be
+used to distinguish the data format. 8DW format is like
+::
+
+ bits [ 31:11 ][ 10:0 ]
+ |---------------------------------------|-------------------|
+ DW0 [ 0x1fffff ][ Reserved (0x7ff) ]
+ DW1 [ Prefix ]
+ DW2 [ Header DW0 ]
+ DW3 [ Header DW1 ]
+ DW4 [ Header DW2 ]
+ DW5 [ Header DW3 ]
+ DW6 [ Reserved (0x0) ]
+ DW7 [ Time ]
+
+When using the 4DW data format, DW0 of the trace buffer entry
+contains selected fields of DW0 of the TLP, together with a
+timestamp. DW1-DW3 of the trace buffer entry contain DW1-DW3
+directly from the TLP header.
+
+4DW format is like
+::
+
+ bits [31:30] [ 29:25 ][24][23][22][21][ 20:11 ][ 10:0 ]
+ |-----|---------|---|---|---|---|-------------|-------------|
+ DW0 [ Fmt ][ Type ][T9][T8][TH][SO][ Length ][ Time ]
+ DW1 [ Header DW1 ]
+ DW2 [ Header DW2 ]
+ DW3 [ Header DW3 ]
+
+5. Memory Management
+--------------------
+
+The traced TLP headers will be written to the memory allocated
+by the driver. The hardware accepts 4 DMA address with same size,
+and writes the buffer sequentially like below. If DMA addr 3 is
+finished and the trace is still on, it will return to addr 0.
+::
+
+ +->[DMA addr 0]->[DMA addr 1]->[DMA addr 2]->[DMA addr 3]-+
+ +---------------------------------------------------------+
+
+Driver will allocate each DMA buffer of 4MiB. The finished buffer
+will be copied to the perf AUX buffer allocated by the perf core.
+Once the AUX buffer is full while the trace is still on, driver
+will commit the AUX buffer first and then apply for a new one with
+the same size. The size of AUX buffer is default to 16MiB. User can
+adjust the size by specifying the `-m` parameter of the perf command.
+
+6. Decoding
+-----------
+
+You can decode the traced data with `perf report -D` command (currently
+only support to dump the raw trace data). The traced data will be decoded
+according to the format described previously (take 8DW as an example):
+::
+
+ [...perf headers and other information]
+ . ... HISI PTT data: size 4194304 bytes
+ . 00000000: 00 00 00 00 Prefix
+ . 00000004: 01 00 00 60 Header DW0
+ . 00000008: 0f 1e 00 01 Header DW1
+ . 0000000c: 04 00 00 00 Header DW2
+ . 00000010: 40 00 81 02 Header DW3
+ . 00000014: 33 c0 04 00 Time
+ . 00000020: 00 00 00 00 Prefix
+ . 00000024: 01 00 00 60 Header DW0
+ . 00000028: 0f 1e 00 01 Header DW1
+ . 0000002c: 04 00 00 00 Header DW2
+ . 00000030: 40 00 81 02 Header DW3
+ . 00000034: 02 00 00 00 Time
+ . 00000040: 00 00 00 00 Prefix
+ . 00000044: 01 00 00 60 Header DW0
+ . 00000048: 0f 1e 00 01 Header DW1
+ . 0000004c: 04 00 00 00 Header DW2
+ . 00000050: 40 00 81 02 Header DW3
+ [...]