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(). ... --- net/ipv4/tcp_lp.c | 354 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 354 insertions(+) create mode 100644 net/ipv4/tcp_lp.c (limited to 'net/ipv4/tcp_lp.c') diff --git a/net/ipv4/tcp_lp.c b/net/ipv4/tcp_lp.c new file mode 100644 index 000000000..ae3678097 --- /dev/null +++ b/net/ipv4/tcp_lp.c @@ -0,0 +1,354 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * TCP Low Priority (TCP-LP) + * + * TCP Low Priority is a distributed algorithm whose goal is to utilize only + * the excess network bandwidth as compared to the ``fair share`` of + * bandwidth as targeted by TCP. + * + * As of 2.6.13, Linux supports pluggable congestion control algorithms. + * Due to the limitation of the API, we take the following changes from + * the original TCP-LP implementation: + * o We use newReno in most core CA handling. Only add some checking + * within cong_avoid. + * o Error correcting in remote HZ, therefore remote HZ will be keeped + * on checking and updating. + * o Handling calculation of One-Way-Delay (OWD) within rtt_sample, since + * OWD have a similar meaning as RTT. Also correct the buggy formular. + * o Handle reaction for Early Congestion Indication (ECI) within + * pkts_acked, as mentioned within pseudo code. + * o OWD is handled in relative format, where local time stamp will in + * tcp_time_stamp format. + * + * Original Author: + * Aleksandar Kuzmanovic + * Available from: + * http://www.ece.rice.edu/~akuzma/Doc/akuzma/TCP-LP.pdf + * Original implementation for 2.4.19: + * http://www-ece.rice.edu/networks/TCP-LP/ + * + * 2.6.x module Authors: + * Wong Hoi Sing, Edison + * Hung Hing Lun, Mike + * SourceForge project page: + * http://tcp-lp-mod.sourceforge.net/ + */ + +#include +#include + +/* resolution of owd */ +#define LP_RESOL TCP_TS_HZ + +/** + * enum tcp_lp_state + * @LP_VALID_RHZ: is remote HZ valid? + * @LP_VALID_OWD: is OWD valid? + * @LP_WITHIN_THR: are we within threshold? + * @LP_WITHIN_INF: are we within inference? + * + * TCP-LP's state flags. + * We create this set of state flag mainly for debugging. + */ +enum tcp_lp_state { + LP_VALID_RHZ = (1 << 0), + LP_VALID_OWD = (1 << 1), + LP_WITHIN_THR = (1 << 3), + LP_WITHIN_INF = (1 << 4), +}; + +/** + * struct lp + * @flag: TCP-LP state flag + * @sowd: smoothed OWD << 3 + * @owd_min: min OWD + * @owd_max: max OWD + * @owd_max_rsv: reserved max owd + * @remote_hz: estimated remote HZ + * @remote_ref_time: remote reference time + * @local_ref_time: local reference time + * @last_drop: time for last active drop + * @inference: current inference + * + * TCP-LP's private struct. + * We get the idea from original TCP-LP implementation where only left those we + * found are really useful. + */ +struct lp { + u32 flag; + u32 sowd; + u32 owd_min; + u32 owd_max; + u32 owd_max_rsv; + u32 remote_hz; + u32 remote_ref_time; + u32 local_ref_time; + u32 last_drop; + u32 inference; +}; + +/** + * tcp_lp_init + * @sk: socket to initialize congestion control algorithm for + * + * Init all required variables. + * Clone the handling from Vegas module implementation. + */ +static void tcp_lp_init(struct sock *sk) +{ + struct lp *lp = inet_csk_ca(sk); + + lp->flag = 0; + lp->sowd = 0; + lp->owd_min = 0xffffffff; + lp->owd_max = 0; + lp->owd_max_rsv = 0; + lp->remote_hz = 0; + lp->remote_ref_time = 0; + lp->local_ref_time = 0; + lp->last_drop = 0; + lp->inference = 0; +} + +/** + * tcp_lp_cong_avoid + * @sk: socket to avoid congesting + * + * Implementation of cong_avoid. + * Will only call newReno CA when away from inference. + * From TCP-LP's paper, this will be handled in additive increasement. + */ +static void tcp_lp_cong_avoid(struct sock *sk, u32 ack, u32 acked) +{ + struct lp *lp = inet_csk_ca(sk); + + if (!(lp->flag & LP_WITHIN_INF)) + tcp_reno_cong_avoid(sk, ack, acked); +} + +/** + * tcp_lp_remote_hz_estimator + * @sk: socket which needs an estimate for the remote HZs + * + * Estimate remote HZ. + * We keep on updating the estimated value, where original TCP-LP + * implementation only guest it for once and use forever. + */ +static u32 tcp_lp_remote_hz_estimator(struct sock *sk) +{ + struct tcp_sock *tp = tcp_sk(sk); + struct lp *lp = inet_csk_ca(sk); + s64 rhz = lp->remote_hz << 6; /* remote HZ << 6 */ + s64 m = 0; + + /* not yet record reference time + * go away!! record it before come back!! */ + if (lp->remote_ref_time == 0 || lp->local_ref_time == 0) + goto out; + + /* we can't calc remote HZ with no different!! */ + if (tp->rx_opt.rcv_tsval == lp->remote_ref_time || + tp->rx_opt.rcv_tsecr == lp->local_ref_time) + goto out; + + m = TCP_TS_HZ * + (tp->rx_opt.rcv_tsval - lp->remote_ref_time) / + (tp->rx_opt.rcv_tsecr - lp->local_ref_time); + if (m < 0) + m = -m; + + if (rhz > 0) { + m -= rhz >> 6; /* m is now error in remote HZ est */ + rhz += m; /* 63/64 old + 1/64 new */ + } else + rhz = m << 6; + + out: + /* record time for successful remote HZ calc */ + if ((rhz >> 6) > 0) + lp->flag |= LP_VALID_RHZ; + else + lp->flag &= ~LP_VALID_RHZ; + + /* record reference time stamp */ + lp->remote_ref_time = tp->rx_opt.rcv_tsval; + lp->local_ref_time = tp->rx_opt.rcv_tsecr; + + return rhz >> 6; +} + +/** + * tcp_lp_owd_calculator + * @sk: socket to calculate one way delay for + * + * Calculate one way delay (in relative format). + * Original implement OWD as minus of remote time difference to local time + * difference directly. As this time difference just simply equal to RTT, when + * the network status is stable, remote RTT will equal to local RTT, and result + * OWD into zero. + * It seems to be a bug and so we fixed it. + */ +static u32 tcp_lp_owd_calculator(struct sock *sk) +{ + struct tcp_sock *tp = tcp_sk(sk); + struct lp *lp = inet_csk_ca(sk); + s64 owd = 0; + + lp->remote_hz = tcp_lp_remote_hz_estimator(sk); + + if (lp->flag & LP_VALID_RHZ) { + owd = + tp->rx_opt.rcv_tsval * (LP_RESOL / lp->remote_hz) - + tp->rx_opt.rcv_tsecr * (LP_RESOL / TCP_TS_HZ); + if (owd < 0) + owd = -owd; + } + + if (owd > 0) + lp->flag |= LP_VALID_OWD; + else + lp->flag &= ~LP_VALID_OWD; + + return owd; +} + +/** + * tcp_lp_rtt_sample + * @sk: socket to add a rtt sample to + * @rtt: round trip time, which is ignored! + * + * Implementation or rtt_sample. + * Will take the following action, + * 1. calc OWD, + * 2. record the min/max OWD, + * 3. calc smoothed OWD (SOWD). + * Most ideas come from the original TCP-LP implementation. + */ +static void tcp_lp_rtt_sample(struct sock *sk, u32 rtt) +{ + struct lp *lp = inet_csk_ca(sk); + s64 mowd = tcp_lp_owd_calculator(sk); + + /* sorry that we don't have valid data */ + if (!(lp->flag & LP_VALID_RHZ) || !(lp->flag & LP_VALID_OWD)) + return; + + /* record the next min owd */ + if (mowd < lp->owd_min) + lp->owd_min = mowd; + + /* always forget the max of the max + * we just set owd_max as one below it */ + if (mowd > lp->owd_max) { + if (mowd > lp->owd_max_rsv) { + if (lp->owd_max_rsv == 0) + lp->owd_max = mowd; + else + lp->owd_max = lp->owd_max_rsv; + lp->owd_max_rsv = mowd; + } else + lp->owd_max = mowd; + } + + /* calc for smoothed owd */ + if (lp->sowd != 0) { + mowd -= lp->sowd >> 3; /* m is now error in owd est */ + lp->sowd += mowd; /* owd = 7/8 owd + 1/8 new */ + } else + lp->sowd = mowd << 3; /* take the measured time be owd */ +} + +/** + * tcp_lp_pkts_acked + * @sk: socket requiring congestion avoidance calculations + * + * Implementation of pkts_acked. + * Deal with active drop under Early Congestion Indication. + * Only drop to half and 1 will be handle, because we hope to use back + * newReno in increase case. + * We work it out by following the idea from TCP-LP's paper directly + */ +static void tcp_lp_pkts_acked(struct sock *sk, const struct ack_sample *sample) +{ + struct tcp_sock *tp = tcp_sk(sk); + struct lp *lp = inet_csk_ca(sk); + u32 now = tcp_time_stamp(tp); + u32 delta; + + if (sample->rtt_us > 0) + tcp_lp_rtt_sample(sk, sample->rtt_us); + + /* calc inference */ + delta = now - tp->rx_opt.rcv_tsecr; + if ((s32)delta > 0) + lp->inference = 3 * delta; + + /* test if within inference */ + if (lp->last_drop && (now - lp->last_drop < lp->inference)) + lp->flag |= LP_WITHIN_INF; + else + lp->flag &= ~LP_WITHIN_INF; + + /* test if within threshold */ + if (lp->sowd >> 3 < + lp->owd_min + 15 * (lp->owd_max - lp->owd_min) / 100) + lp->flag |= LP_WITHIN_THR; + else + lp->flag &= ~LP_WITHIN_THR; + + pr_debug("TCP-LP: %05o|%5u|%5u|%15u|%15u|%15u\n", lp->flag, + tcp_snd_cwnd(tp), lp->remote_hz, lp->owd_min, lp->owd_max, + lp->sowd >> 3); + + if (lp->flag & LP_WITHIN_THR) + return; + + /* FIXME: try to reset owd_min and owd_max here + * so decrease the chance the min/max is no longer suitable + * and will usually within threshold when within inference */ + lp->owd_min = lp->sowd >> 3; + lp->owd_max = lp->sowd >> 2; + lp->owd_max_rsv = lp->sowd >> 2; + + /* happened within inference + * drop snd_cwnd into 1 */ + if (lp->flag & LP_WITHIN_INF) + tcp_snd_cwnd_set(tp, 1U); + + /* happened after inference + * cut snd_cwnd into half */ + else + tcp_snd_cwnd_set(tp, max(tcp_snd_cwnd(tp) >> 1U, 1U)); + + /* record this drop time */ + lp->last_drop = now; +} + +static struct tcp_congestion_ops tcp_lp __read_mostly = { + .init = tcp_lp_init, + .ssthresh = tcp_reno_ssthresh, + .undo_cwnd = tcp_reno_undo_cwnd, + .cong_avoid = tcp_lp_cong_avoid, + .pkts_acked = tcp_lp_pkts_acked, + + .owner = THIS_MODULE, + .name = "lp" +}; + +static int __init tcp_lp_register(void) +{ + BUILD_BUG_ON(sizeof(struct lp) > ICSK_CA_PRIV_SIZE); + return tcp_register_congestion_control(&tcp_lp); +} + +static void __exit tcp_lp_unregister(void) +{ + tcp_unregister_congestion_control(&tcp_lp); +} + +module_init(tcp_lp_register); +module_exit(tcp_lp_unregister); + +MODULE_AUTHOR("Wong Hoi Sing Edison, Hung Hing Lun Mike"); +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("TCP Low Priority"); -- cgit v1.2.3