From 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Tue, 21 Feb 2023 18:24:12 -0800 Subject: Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 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(). ... --- Documentation/networking/pktgen.rst | 410 ++++++++++++++++++++++++++++++++++++ 1 file changed, 410 insertions(+) create mode 100644 Documentation/networking/pktgen.rst (limited to 'Documentation/networking/pktgen.rst') diff --git a/Documentation/networking/pktgen.rst b/Documentation/networking/pktgen.rst new file mode 100644 index 000000000..1225f0f63 --- /dev/null +++ b/Documentation/networking/pktgen.rst @@ -0,0 +1,410 @@ +.. SPDX-License-Identifier: GPL-2.0 + +==================================== +HOWTO for the linux packet generator +==================================== + +Enable CONFIG_NET_PKTGEN to compile and build pktgen either in-kernel +or as a module. A module is preferred; modprobe pktgen if needed. Once +running, pktgen creates a thread for each CPU with affinity to that CPU. +Monitoring and controlling is done via /proc. It is easiest to select a +suitable sample script and configure that. + +On a dual CPU:: + + ps aux | grep pkt + root 129 0.3 0.0 0 0 ? SW 2003 523:20 [kpktgend_0] + root 130 0.3 0.0 0 0 ? SW 2003 509:50 [kpktgend_1] + + +For monitoring and control pktgen creates:: + + /proc/net/pktgen/pgctrl + /proc/net/pktgen/kpktgend_X + /proc/net/pktgen/ethX + + +Tuning NIC for max performance +============================== + +The default NIC settings are (likely) not tuned for pktgen's artificial +overload type of benchmarking, as this could hurt the normal use-case. + +Specifically increasing the TX ring buffer in the NIC:: + + # ethtool -G ethX tx 1024 + +A larger TX ring can improve pktgen's performance, while it can hurt +in the general case, 1) because the TX ring buffer might get larger +than the CPU's L1/L2 cache, 2) because it allows more queueing in the +NIC HW layer (which is bad for bufferbloat). + +One should hesitate to conclude that packets/descriptors in the HW +TX ring cause delay. Drivers usually delay cleaning up the +ring-buffers for various performance reasons, and packets stalling +the TX ring might just be waiting for cleanup. + +This cleanup issue is specifically the case for the driver ixgbe +(Intel 82599 chip). This driver (ixgbe) combines TX+RX ring cleanups, +and the cleanup interval is affected by the ethtool --coalesce setting +of parameter "rx-usecs". + +For ixgbe use e.g. "30" resulting in approx 33K interrupts/sec (1/30*10^6):: + + # ethtool -C ethX rx-usecs 30 + + +Kernel threads +============== +Pktgen creates a thread for each CPU with affinity to that CPU. +Which is controlled through procfile /proc/net/pktgen/kpktgend_X. + +Example: /proc/net/pktgen/kpktgend_0:: + + Running: + Stopped: eth4@0 + Result: OK: add_device=eth4@0 + +Most important are the devices assigned to the thread. + +The two basic thread commands are: + + * add_device DEVICE@NAME -- adds a single device + * rem_device_all -- remove all associated devices + +When adding a device to a thread, a corresponding procfile is created +which is used for configuring this device. Thus, device names need to +be unique. + +To support adding the same device to multiple threads, which is useful +with multi queue NICs, the device naming scheme is extended with "@": +device@something + +The part after "@" can be anything, but it is custom to use the thread +number. + +Viewing devices +=============== + +The Params section holds configured information. The Current section +holds running statistics. The Result is printed after a run or after +interruption. Example:: + + /proc/net/pktgen/eth4@0 + + Params: count 100000 min_pkt_size: 60 max_pkt_size: 60 + frags: 0 delay: 0 clone_skb: 64 ifname: eth4@0 + flows: 0 flowlen: 0 + queue_map_min: 0 queue_map_max: 0 + dst_min: 192.168.81.2 dst_max: + src_min: src_max: + src_mac: 90:e2:ba:0a:56:b4 dst_mac: 00:1b:21:3c:9d:f8 + udp_src_min: 9 udp_src_max: 109 udp_dst_min: 9 udp_dst_max: 9 + src_mac_count: 0 dst_mac_count: 0 + Flags: UDPSRC_RND NO_TIMESTAMP QUEUE_MAP_CPU + Current: + pkts-sofar: 100000 errors: 0 + started: 623913381008us stopped: 623913396439us idle: 25us + seq_num: 100001 cur_dst_mac_offset: 0 cur_src_mac_offset: 0 + cur_saddr: 192.168.8.3 cur_daddr: 192.168.81.2 + cur_udp_dst: 9 cur_udp_src: 42 + cur_queue_map: 0 + flows: 0 + Result: OK: 15430(c15405+d25) usec, 100000 (60byte,0frags) + 6480562pps 3110Mb/sec (3110669760bps) errors: 0 + + +Configuring devices +=================== +This is done via the /proc interface, and most easily done via pgset +as defined in the sample scripts. +You need to specify PGDEV environment variable to use functions from sample +scripts, i.e.:: + + export PGDEV=/proc/net/pktgen/eth4@0 + source samples/pktgen/functions.sh + +Examples:: + + pg_ctrl start starts injection. + pg_ctrl stop aborts injection. Also, ^C aborts generator. + + pgset "clone_skb 1" sets the number of copies of the same packet + pgset "clone_skb 0" use single SKB for all transmits + pgset "burst 8" uses xmit_more API to queue 8 copies of the same + packet and update HW tx queue tail pointer once. + "burst 1" is the default + pgset "pkt_size 9014" sets packet size to 9014 + pgset "frags 5" packet will consist of 5 fragments + pgset "count 200000" sets number of packets to send, set to zero + for continuous sends until explicitly stopped. + + pgset "delay 5000" adds delay to hard_start_xmit(). nanoseconds + + pgset "dst 10.0.0.1" sets IP destination address + (BEWARE! This generator is very aggressive!) + + pgset "dst_min 10.0.0.1" Same as dst + pgset "dst_max 10.0.0.254" Set the maximum destination IP. + pgset "src_min 10.0.0.1" Set the minimum (or only) source IP. + pgset "src_max 10.0.0.254" Set the maximum source IP. + pgset "dst6 fec0::1" IPV6 destination address + pgset "src6 fec0::2" IPV6 source address + pgset "dstmac 00:00:00:00:00:00" sets MAC destination address + pgset "srcmac 00:00:00:00:00:00" sets MAC source address + + pgset "queue_map_min 0" Sets the min value of tx queue interval + pgset "queue_map_max 7" Sets the max value of tx queue interval, for multiqueue devices + To select queue 1 of a given device, + use queue_map_min=1 and queue_map_max=1 + + pgset "src_mac_count 1" Sets the number of MACs we'll range through. + The 'minimum' MAC is what you set with srcmac. + + pgset "dst_mac_count 1" Sets the number of MACs we'll range through. + The 'minimum' MAC is what you set with dstmac. + + pgset "flag [name]" Set a flag to determine behaviour. Current flags + are: IPSRC_RND # IP source is random (between min/max) + IPDST_RND # IP destination is random + UDPSRC_RND, UDPDST_RND, + MACSRC_RND, MACDST_RND + TXSIZE_RND, IPV6, + MPLS_RND, VID_RND, SVID_RND + FLOW_SEQ, + QUEUE_MAP_RND # queue map random + QUEUE_MAP_CPU # queue map mirrors smp_processor_id() + UDPCSUM, + IPSEC # IPsec encapsulation (needs CONFIG_XFRM) + NODE_ALLOC # node specific memory allocation + NO_TIMESTAMP # disable timestamping + pgset 'flag ![name]' Clear a flag to determine behaviour. + Note that you might need to use single quote in + interactive mode, so that your shell wouldn't expand + the specified flag as a history command. + + pgset "spi [SPI_VALUE]" Set specific SA used to transform packet. + + pgset "udp_src_min 9" set UDP source port min, If < udp_src_max, then + cycle through the port range. + + pgset "udp_src_max 9" set UDP source port max. + pgset "udp_dst_min 9" set UDP destination port min, If < udp_dst_max, then + cycle through the port range. + pgset "udp_dst_max 9" set UDP destination port max. + + pgset "mpls 0001000a,0002000a,0000000a" set MPLS labels (in this example + outer label=16,middle label=32, + inner label=0 (IPv4 NULL)) Note that + there must be no spaces between the + arguments. Leading zeros are required. + Do not set the bottom of stack bit, + that's done automatically. If you do + set the bottom of stack bit, that + indicates that you want to randomly + generate that address and the flag + MPLS_RND will be turned on. You + can have any mix of random and fixed + labels in the label stack. + + pgset "mpls 0" turn off mpls (or any invalid argument works too!) + + pgset "vlan_id 77" set VLAN ID 0-4095 + pgset "vlan_p 3" set priority bit 0-7 (default 0) + pgset "vlan_cfi 0" set canonical format identifier 0-1 (default 0) + + pgset "svlan_id 22" set SVLAN ID 0-4095 + pgset "svlan_p 3" set priority bit 0-7 (default 0) + pgset "svlan_cfi 0" set canonical format identifier 0-1 (default 0) + + pgset "vlan_id 9999" > 4095 remove vlan and svlan tags + pgset "svlan 9999" > 4095 remove svlan tag + + + pgset "tos XX" set former IPv4 TOS field (e.g. "tos 28" for AF11 no ECN, default 00) + pgset "traffic_class XX" set former IPv6 TRAFFIC CLASS (e.g. "traffic_class B8" for EF no ECN, default 00) + + pgset "rate 300M" set rate to 300 Mb/s + pgset "ratep 1000000" set rate to 1Mpps + + pgset "xmit_mode netif_receive" RX inject into stack netif_receive_skb() + Works with "burst" but not with "clone_skb". + Default xmit_mode is "start_xmit". + +Sample scripts +============== + +A collection of tutorial scripts and helpers for pktgen is in the +samples/pktgen directory. The helper parameters.sh file support easy +and consistent parameter parsing across the sample scripts. + +Usage example and help:: + + ./pktgen_sample01_simple.sh -i eth4 -m 00:1B:21:3C:9D:F8 -d 192.168.8.2 + +Usage::: + + ./pktgen_sample01_simple.sh [-vx] -i ethX + + -i : ($DEV) output interface/device (required) + -s : ($PKT_SIZE) packet size + -d : ($DEST_IP) destination IP. CIDR (e.g. 198.18.0.0/15) is also allowed + -m : ($DST_MAC) destination MAC-addr + -p : ($DST_PORT) destination PORT range (e.g. 433-444) is also allowed + -t : ($THREADS) threads to start + -f : ($F_THREAD) index of first thread (zero indexed CPU number) + -c : ($SKB_CLONE) SKB clones send before alloc new SKB + -n : ($COUNT) num messages to send per thread, 0 means indefinitely + -b : ($BURST) HW level bursting of SKBs + -v : ($VERBOSE) verbose + -x : ($DEBUG) debug + -6 : ($IP6) IPv6 + -w : ($DELAY) Tx Delay value (ns) + -a : ($APPEND) Script will not reset generator's state, but will append its config + +The global variables being set are also listed. E.g. the required +interface/device parameter "-i" sets variable $DEV. Copy the +pktgen_sampleXX scripts and modify them to fit your own needs. + + +Interrupt affinity +=================== +Note that when adding devices to a specific CPU it is a good idea to +also assign /proc/irq/XX/smp_affinity so that the TX interrupts are bound +to the same CPU. This reduces cache bouncing when freeing skbs. + +Plus using the device flag QUEUE_MAP_CPU, which maps the SKBs TX queue +to the running threads CPU (directly from smp_processor_id()). + +Enable IPsec +============ +Default IPsec transformation with ESP encapsulation plus transport mode +can be enabled by simply setting:: + + pgset "flag IPSEC" + pgset "flows 1" + +To avoid breaking existing testbed scripts for using AH type and tunnel mode, +you can use "pgset spi SPI_VALUE" to specify which transformation mode +to employ. + + +Current commands and configuration options +========================================== + +**Pgcontrol commands**:: + + start + stop + reset + +**Thread commands**:: + + add_device + rem_device_all + + +**Device commands**:: + + count + clone_skb + burst + debug + + frags + delay + + src_mac_count + dst_mac_count + + pkt_size + min_pkt_size + max_pkt_size + + queue_map_min + queue_map_max + skb_priority + + tos (ipv4) + traffic_class (ipv6) + + mpls + + udp_src_min + udp_src_max + + udp_dst_min + udp_dst_max + + node + + flag + IPSRC_RND + IPDST_RND + UDPSRC_RND + UDPDST_RND + MACSRC_RND + MACDST_RND + TXSIZE_RND + IPV6 + MPLS_RND + VID_RND + SVID_RND + FLOW_SEQ + QUEUE_MAP_RND + QUEUE_MAP_CPU + UDPCSUM + IPSEC + NODE_ALLOC + NO_TIMESTAMP + + spi (ipsec) + + dst_min + dst_max + + src_min + src_max + + dst_mac + src_mac + + clear_counters + + src6 + dst6 + dst6_max + dst6_min + + flows + flowlen + + rate + ratep + + xmit_mode + + vlan_cfi + vlan_id + vlan_p + + svlan_cfi + svlan_id + svlan_p + + +References: + +- ftp://robur.slu.se/pub/Linux/net-development/pktgen-testing/ +- ftp://robur.slu.se/pub/Linux/net-development/pktgen-testing/examples/ + +Paper from Linux-Kongress in Erlangen 2004. +- ftp://robur.slu.se/pub/Linux/net-development/pktgen-testing/pktgen_paper.pdf + +Thanks to: + +Grant Grundler for testing on IA-64 and parisc, Harald Welte, Lennert Buytenhek +Stephen Hemminger, Andi Kleen, Dave Miller and many others. + + +Good luck with the linux net-development. -- cgit v1.2.3