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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
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /lib/flex_proportions.c
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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(). ...
Diffstat (limited to 'lib/flex_proportions.c')
-rw-r--r--lib/flex_proportions.c278
1 files changed, 278 insertions, 0 deletions
diff --git a/lib/flex_proportions.c b/lib/flex_proportions.c
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--- /dev/null
+++ b/lib/flex_proportions.c
@@ -0,0 +1,278 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Floating proportions with flexible aging period
+ *
+ * Copyright (C) 2011, SUSE, Jan Kara <jack@suse.cz>
+ *
+ * The goal of this code is: Given different types of event, measure proportion
+ * of each type of event over time. The proportions are measured with
+ * exponentially decaying history to give smooth transitions. A formula
+ * expressing proportion of event of type 'j' is:
+ *
+ * p_{j} = (\Sum_{i>=0} x_{i,j}/2^{i+1})/(\Sum_{i>=0} x_i/2^{i+1})
+ *
+ * Where x_{i,j} is j's number of events in i-th last time period and x_i is
+ * total number of events in i-th last time period.
+ *
+ * Note that p_{j}'s are normalised, i.e.
+ *
+ * \Sum_{j} p_{j} = 1,
+ *
+ * This formula can be straightforwardly computed by maintaining denominator
+ * (let's call it 'd') and for each event type its numerator (let's call it
+ * 'n_j'). When an event of type 'j' happens, we simply need to do:
+ * n_j++; d++;
+ *
+ * When a new period is declared, we could do:
+ * d /= 2
+ * for each j
+ * n_j /= 2
+ *
+ * To avoid iteration over all event types, we instead shift numerator of event
+ * j lazily when someone asks for a proportion of event j or when event j
+ * occurs. This can bit trivially implemented by remembering last period in
+ * which something happened with proportion of type j.
+ */
+#include <linux/flex_proportions.h>
+
+int fprop_global_init(struct fprop_global *p, gfp_t gfp)
+{
+ int err;
+
+ p->period = 0;
+ /* Use 1 to avoid dealing with periods with 0 events... */
+ err = percpu_counter_init(&p->events, 1, gfp);
+ if (err)
+ return err;
+ seqcount_init(&p->sequence);
+ return 0;
+}
+
+void fprop_global_destroy(struct fprop_global *p)
+{
+ percpu_counter_destroy(&p->events);
+}
+
+/*
+ * Declare @periods new periods. It is upto the caller to make sure period
+ * transitions cannot happen in parallel.
+ *
+ * The function returns true if the proportions are still defined and false
+ * if aging zeroed out all events. This can be used to detect whether declaring
+ * further periods has any effect.
+ */
+bool fprop_new_period(struct fprop_global *p, int periods)
+{
+ s64 events = percpu_counter_sum(&p->events);
+
+ /*
+ * Don't do anything if there are no events.
+ */
+ if (events <= 1)
+ return false;
+ preempt_disable_nested();
+ write_seqcount_begin(&p->sequence);
+ if (periods < 64)
+ events -= events >> periods;
+ /* Use addition to avoid losing events happening between sum and set */
+ percpu_counter_add(&p->events, -events);
+ p->period += periods;
+ write_seqcount_end(&p->sequence);
+ preempt_enable_nested();
+
+ return true;
+}
+
+/*
+ * ---- SINGLE ----
+ */
+
+int fprop_local_init_single(struct fprop_local_single *pl)
+{
+ pl->events = 0;
+ pl->period = 0;
+ raw_spin_lock_init(&pl->lock);
+ return 0;
+}
+
+void fprop_local_destroy_single(struct fprop_local_single *pl)
+{
+}
+
+static void fprop_reflect_period_single(struct fprop_global *p,
+ struct fprop_local_single *pl)
+{
+ unsigned int period = p->period;
+ unsigned long flags;
+
+ /* Fast path - period didn't change */
+ if (pl->period == period)
+ return;
+ raw_spin_lock_irqsave(&pl->lock, flags);
+ /* Someone updated pl->period while we were spinning? */
+ if (pl->period >= period) {
+ raw_spin_unlock_irqrestore(&pl->lock, flags);
+ return;
+ }
+ /* Aging zeroed our fraction? */
+ if (period - pl->period < BITS_PER_LONG)
+ pl->events >>= period - pl->period;
+ else
+ pl->events = 0;
+ pl->period = period;
+ raw_spin_unlock_irqrestore(&pl->lock, flags);
+}
+
+/* Event of type pl happened */
+void __fprop_inc_single(struct fprop_global *p, struct fprop_local_single *pl)
+{
+ fprop_reflect_period_single(p, pl);
+ pl->events++;
+ percpu_counter_add(&p->events, 1);
+}
+
+/* Return fraction of events of type pl */
+void fprop_fraction_single(struct fprop_global *p,
+ struct fprop_local_single *pl,
+ unsigned long *numerator, unsigned long *denominator)
+{
+ unsigned int seq;
+ s64 num, den;
+
+ do {
+ seq = read_seqcount_begin(&p->sequence);
+ fprop_reflect_period_single(p, pl);
+ num = pl->events;
+ den = percpu_counter_read_positive(&p->events);
+ } while (read_seqcount_retry(&p->sequence, seq));
+
+ /*
+ * Make fraction <= 1 and denominator > 0 even in presence of percpu
+ * counter errors
+ */
+ if (den <= num) {
+ if (num)
+ den = num;
+ else
+ den = 1;
+ }
+ *denominator = den;
+ *numerator = num;
+}
+
+/*
+ * ---- PERCPU ----
+ */
+#define PROP_BATCH (8*(1+ilog2(nr_cpu_ids)))
+
+int fprop_local_init_percpu(struct fprop_local_percpu *pl, gfp_t gfp)
+{
+ int err;
+
+ err = percpu_counter_init(&pl->events, 0, gfp);
+ if (err)
+ return err;
+ pl->period = 0;
+ raw_spin_lock_init(&pl->lock);
+ return 0;
+}
+
+void fprop_local_destroy_percpu(struct fprop_local_percpu *pl)
+{
+ percpu_counter_destroy(&pl->events);
+}
+
+static void fprop_reflect_period_percpu(struct fprop_global *p,
+ struct fprop_local_percpu *pl)
+{
+ unsigned int period = p->period;
+ unsigned long flags;
+
+ /* Fast path - period didn't change */
+ if (pl->period == period)
+ return;
+ raw_spin_lock_irqsave(&pl->lock, flags);
+ /* Someone updated pl->period while we were spinning? */
+ if (pl->period >= period) {
+ raw_spin_unlock_irqrestore(&pl->lock, flags);
+ return;
+ }
+ /* Aging zeroed our fraction? */
+ if (period - pl->period < BITS_PER_LONG) {
+ s64 val = percpu_counter_read(&pl->events);
+
+ if (val < (nr_cpu_ids * PROP_BATCH))
+ val = percpu_counter_sum(&pl->events);
+
+ percpu_counter_add_batch(&pl->events,
+ -val + (val >> (period-pl->period)), PROP_BATCH);
+ } else
+ percpu_counter_set(&pl->events, 0);
+ pl->period = period;
+ raw_spin_unlock_irqrestore(&pl->lock, flags);
+}
+
+/* Event of type pl happened */
+void __fprop_add_percpu(struct fprop_global *p, struct fprop_local_percpu *pl,
+ long nr)
+{
+ fprop_reflect_period_percpu(p, pl);
+ percpu_counter_add_batch(&pl->events, nr, PROP_BATCH);
+ percpu_counter_add(&p->events, nr);
+}
+
+void fprop_fraction_percpu(struct fprop_global *p,
+ struct fprop_local_percpu *pl,
+ unsigned long *numerator, unsigned long *denominator)
+{
+ unsigned int seq;
+ s64 num, den;
+
+ do {
+ seq = read_seqcount_begin(&p->sequence);
+ fprop_reflect_period_percpu(p, pl);
+ num = percpu_counter_read_positive(&pl->events);
+ den = percpu_counter_read_positive(&p->events);
+ } while (read_seqcount_retry(&p->sequence, seq));
+
+ /*
+ * Make fraction <= 1 and denominator > 0 even in presence of percpu
+ * counter errors
+ */
+ if (den <= num) {
+ if (num)
+ den = num;
+ else
+ den = 1;
+ }
+ *denominator = den;
+ *numerator = num;
+}
+
+/*
+ * Like __fprop_add_percpu() except that event is counted only if the given
+ * type has fraction smaller than @max_frac/FPROP_FRAC_BASE
+ */
+void __fprop_add_percpu_max(struct fprop_global *p,
+ struct fprop_local_percpu *pl, int max_frac, long nr)
+{
+ if (unlikely(max_frac < FPROP_FRAC_BASE)) {
+ unsigned long numerator, denominator;
+ s64 tmp;
+
+ fprop_fraction_percpu(p, pl, &numerator, &denominator);
+ /* Adding 'nr' to fraction exceeds max_frac/FPROP_FRAC_BASE? */
+ tmp = (u64)denominator * max_frac -
+ ((u64)numerator << FPROP_FRAC_SHIFT);
+ if (tmp < 0) {
+ /* Maximum fraction already exceeded? */
+ return;
+ } else if (tmp < nr * (FPROP_FRAC_BASE - max_frac)) {
+ /* Add just enough for the fraction to saturate */
+ nr = div_u64(tmp + FPROP_FRAC_BASE - max_frac - 1,
+ FPROP_FRAC_BASE - max_frac);
+ }
+ }
+
+ __fprop_add_percpu(p, pl, nr);
+}