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(). ... --- lib/percpu_counter.c | 274 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 274 insertions(+) create mode 100644 lib/percpu_counter.c (limited to 'lib/percpu_counter.c') diff --git a/lib/percpu_counter.c b/lib/percpu_counter.c new file mode 100644 index 000000000..42f729c8e --- /dev/null +++ b/lib/percpu_counter.c @@ -0,0 +1,274 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Fast batching percpu counters. + */ + +#include +#include +#include +#include +#include +#include + +#ifdef CONFIG_HOTPLUG_CPU +static LIST_HEAD(percpu_counters); +static DEFINE_SPINLOCK(percpu_counters_lock); +#endif + +#ifdef CONFIG_DEBUG_OBJECTS_PERCPU_COUNTER + +static const struct debug_obj_descr percpu_counter_debug_descr; + +static bool percpu_counter_fixup_free(void *addr, enum debug_obj_state state) +{ + struct percpu_counter *fbc = addr; + + switch (state) { + case ODEBUG_STATE_ACTIVE: + percpu_counter_destroy(fbc); + debug_object_free(fbc, &percpu_counter_debug_descr); + return true; + default: + return false; + } +} + +static const struct debug_obj_descr percpu_counter_debug_descr = { + .name = "percpu_counter", + .fixup_free = percpu_counter_fixup_free, +}; + +static inline void debug_percpu_counter_activate(struct percpu_counter *fbc) +{ + debug_object_init(fbc, &percpu_counter_debug_descr); + debug_object_activate(fbc, &percpu_counter_debug_descr); +} + +static inline void debug_percpu_counter_deactivate(struct percpu_counter *fbc) +{ + debug_object_deactivate(fbc, &percpu_counter_debug_descr); + debug_object_free(fbc, &percpu_counter_debug_descr); +} + +#else /* CONFIG_DEBUG_OBJECTS_PERCPU_COUNTER */ +static inline void debug_percpu_counter_activate(struct percpu_counter *fbc) +{ } +static inline void debug_percpu_counter_deactivate(struct percpu_counter *fbc) +{ } +#endif /* CONFIG_DEBUG_OBJECTS_PERCPU_COUNTER */ + +void percpu_counter_set(struct percpu_counter *fbc, s64 amount) +{ + int cpu; + unsigned long flags; + + raw_spin_lock_irqsave(&fbc->lock, flags); + for_each_possible_cpu(cpu) { + s32 *pcount = per_cpu_ptr(fbc->counters, cpu); + *pcount = 0; + } + fbc->count = amount; + raw_spin_unlock_irqrestore(&fbc->lock, flags); +} +EXPORT_SYMBOL(percpu_counter_set); + +/* + * This function is both preempt and irq safe. The former is due to explicit + * preemption disable. The latter is guaranteed by the fact that the slow path + * is explicitly protected by an irq-safe spinlock whereas the fast patch uses + * this_cpu_add which is irq-safe by definition. Hence there is no need muck + * with irq state before calling this one + */ +void percpu_counter_add_batch(struct percpu_counter *fbc, s64 amount, s32 batch) +{ + s64 count; + + preempt_disable(); + count = __this_cpu_read(*fbc->counters) + amount; + if (abs(count) >= batch) { + unsigned long flags; + raw_spin_lock_irqsave(&fbc->lock, flags); + fbc->count += count; + __this_cpu_sub(*fbc->counters, count - amount); + raw_spin_unlock_irqrestore(&fbc->lock, flags); + } else { + this_cpu_add(*fbc->counters, amount); + } + preempt_enable(); +} +EXPORT_SYMBOL(percpu_counter_add_batch); + +/* + * For percpu_counter with a big batch, the devication of its count could + * be big, and there is requirement to reduce the deviation, like when the + * counter's batch could be runtime decreased to get a better accuracy, + * which can be achieved by running this sync function on each CPU. + */ +void percpu_counter_sync(struct percpu_counter *fbc) +{ + unsigned long flags; + s64 count; + + raw_spin_lock_irqsave(&fbc->lock, flags); + count = __this_cpu_read(*fbc->counters); + fbc->count += count; + __this_cpu_sub(*fbc->counters, count); + raw_spin_unlock_irqrestore(&fbc->lock, flags); +} +EXPORT_SYMBOL(percpu_counter_sync); + +static s64 __percpu_counter_sum_mask(struct percpu_counter *fbc, + const struct cpumask *cpu_mask) +{ + s64 ret; + int cpu; + unsigned long flags; + + raw_spin_lock_irqsave(&fbc->lock, flags); + ret = fbc->count; + for_each_cpu(cpu, cpu_mask) { + s32 *pcount = per_cpu_ptr(fbc->counters, cpu); + ret += *pcount; + } + raw_spin_unlock_irqrestore(&fbc->lock, flags); + return ret; +} + +/* + * Add up all the per-cpu counts, return the result. This is a more accurate + * but much slower version of percpu_counter_read_positive() + */ +s64 __percpu_counter_sum(struct percpu_counter *fbc) +{ + return __percpu_counter_sum_mask(fbc, cpu_online_mask); +} +EXPORT_SYMBOL(__percpu_counter_sum); + +/* + * This is slower version of percpu_counter_sum as it traverses all possible + * cpus. Use this only in the cases where accurate data is needed in the + * presense of CPUs getting offlined. + */ +s64 percpu_counter_sum_all(struct percpu_counter *fbc) +{ + return __percpu_counter_sum_mask(fbc, cpu_possible_mask); +} +EXPORT_SYMBOL(percpu_counter_sum_all); + +int __percpu_counter_init(struct percpu_counter *fbc, s64 amount, gfp_t gfp, + struct lock_class_key *key) +{ + unsigned long flags __maybe_unused; + + raw_spin_lock_init(&fbc->lock); + lockdep_set_class(&fbc->lock, key); + fbc->count = amount; + fbc->counters = alloc_percpu_gfp(s32, gfp); + if (!fbc->counters) + return -ENOMEM; + + debug_percpu_counter_activate(fbc); + +#ifdef CONFIG_HOTPLUG_CPU + INIT_LIST_HEAD(&fbc->list); + spin_lock_irqsave(&percpu_counters_lock, flags); + list_add(&fbc->list, &percpu_counters); + spin_unlock_irqrestore(&percpu_counters_lock, flags); +#endif + return 0; +} +EXPORT_SYMBOL(__percpu_counter_init); + +void percpu_counter_destroy(struct percpu_counter *fbc) +{ + unsigned long flags __maybe_unused; + + if (!fbc->counters) + return; + + debug_percpu_counter_deactivate(fbc); + +#ifdef CONFIG_HOTPLUG_CPU + spin_lock_irqsave(&percpu_counters_lock, flags); + list_del(&fbc->list); + spin_unlock_irqrestore(&percpu_counters_lock, flags); +#endif + free_percpu(fbc->counters); + fbc->counters = NULL; +} +EXPORT_SYMBOL(percpu_counter_destroy); + +int percpu_counter_batch __read_mostly = 32; +EXPORT_SYMBOL(percpu_counter_batch); + +static int compute_batch_value(unsigned int cpu) +{ + int nr = num_online_cpus(); + + percpu_counter_batch = max(32, nr*2); + return 0; +} + +static int percpu_counter_cpu_dead(unsigned int cpu) +{ +#ifdef CONFIG_HOTPLUG_CPU + struct percpu_counter *fbc; + + compute_batch_value(cpu); + + spin_lock_irq(&percpu_counters_lock); + list_for_each_entry(fbc, &percpu_counters, list) { + s32 *pcount; + + raw_spin_lock(&fbc->lock); + pcount = per_cpu_ptr(fbc->counters, cpu); + fbc->count += *pcount; + *pcount = 0; + raw_spin_unlock(&fbc->lock); + } + spin_unlock_irq(&percpu_counters_lock); +#endif + return 0; +} + +/* + * Compare counter against given value. + * Return 1 if greater, 0 if equal and -1 if less + */ +int __percpu_counter_compare(struct percpu_counter *fbc, s64 rhs, s32 batch) +{ + s64 count; + + count = percpu_counter_read(fbc); + /* Check to see if rough count will be sufficient for comparison */ + if (abs(count - rhs) > (batch * num_online_cpus())) { + if (count > rhs) + return 1; + else + return -1; + } + /* Need to use precise count */ + count = percpu_counter_sum(fbc); + if (count > rhs) + return 1; + else if (count < rhs) + return -1; + else + return 0; +} +EXPORT_SYMBOL(__percpu_counter_compare); + +static int __init percpu_counter_startup(void) +{ + int ret; + + ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "lib/percpu_cnt:online", + compute_batch_value, NULL); + WARN_ON(ret < 0); + ret = cpuhp_setup_state_nocalls(CPUHP_PERCPU_CNT_DEAD, + "lib/percpu_cnt:dead", NULL, + percpu_counter_cpu_dead); + WARN_ON(ret < 0); + return 0; +} +module_init(percpu_counter_startup); -- cgit v1.2.3