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/list_sort.c | 253 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 253 insertions(+) create mode 100644 lib/list_sort.c (limited to 'lib/list_sort.c') diff --git a/lib/list_sort.c b/lib/list_sort.c new file mode 100644 index 000000000..0fb59e92c --- /dev/null +++ b/lib/list_sort.c @@ -0,0 +1,253 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include +#include +#include +#include + +/* + * Returns a list organized in an intermediate format suited + * to chaining of merge() calls: null-terminated, no reserved or + * sentinel head node, "prev" links not maintained. + */ +__attribute__((nonnull(2,3,4))) +static struct list_head *merge(void *priv, list_cmp_func_t cmp, + struct list_head *a, struct list_head *b) +{ + struct list_head *head, **tail = &head; + + for (;;) { + /* if equal, take 'a' -- important for sort stability */ + if (cmp(priv, a, b) <= 0) { + *tail = a; + tail = &a->next; + a = a->next; + if (!a) { + *tail = b; + break; + } + } else { + *tail = b; + tail = &b->next; + b = b->next; + if (!b) { + *tail = a; + break; + } + } + } + return head; +} + +/* + * Combine final list merge with restoration of standard doubly-linked + * list structure. This approach duplicates code from merge(), but + * runs faster than the tidier alternatives of either a separate final + * prev-link restoration pass, or maintaining the prev links + * throughout. + */ +__attribute__((nonnull(2,3,4,5))) +static void merge_final(void *priv, list_cmp_func_t cmp, struct list_head *head, + struct list_head *a, struct list_head *b) +{ + struct list_head *tail = head; + u8 count = 0; + + for (;;) { + /* if equal, take 'a' -- important for sort stability */ + if (cmp(priv, a, b) <= 0) { + tail->next = a; + a->prev = tail; + tail = a; + a = a->next; + if (!a) + break; + } else { + tail->next = b; + b->prev = tail; + tail = b; + b = b->next; + if (!b) { + b = a; + break; + } + } + } + + /* Finish linking remainder of list b on to tail */ + tail->next = b; + do { + /* + * If the merge is highly unbalanced (e.g. the input is + * already sorted), this loop may run many iterations. + * Continue callbacks to the client even though no + * element comparison is needed, so the client's cmp() + * routine can invoke cond_resched() periodically. + */ + if (unlikely(!++count)) + cmp(priv, b, b); + b->prev = tail; + tail = b; + b = b->next; + } while (b); + + /* And the final links to make a circular doubly-linked list */ + tail->next = head; + head->prev = tail; +} + +/** + * list_sort - sort a list + * @priv: private data, opaque to list_sort(), passed to @cmp + * @head: the list to sort + * @cmp: the elements comparison function + * + * The comparison function @cmp must return > 0 if @a should sort after + * @b ("@a > @b" if you want an ascending sort), and <= 0 if @a should + * sort before @b *or* their original order should be preserved. It is + * always called with the element that came first in the input in @a, + * and list_sort is a stable sort, so it is not necessary to distinguish + * the @a < @b and @a == @b cases. + * + * This is compatible with two styles of @cmp function: + * - The traditional style which returns <0 / =0 / >0, or + * - Returning a boolean 0/1. + * The latter offers a chance to save a few cycles in the comparison + * (which is used by e.g. plug_ctx_cmp() in block/blk-mq.c). + * + * A good way to write a multi-word comparison is:: + * + * if (a->high != b->high) + * return a->high > b->high; + * if (a->middle != b->middle) + * return a->middle > b->middle; + * return a->low > b->low; + * + * + * This mergesort is as eager as possible while always performing at least + * 2:1 balanced merges. Given two pending sublists of size 2^k, they are + * merged to a size-2^(k+1) list as soon as we have 2^k following elements. + * + * Thus, it will avoid cache thrashing as long as 3*2^k elements can + * fit into the cache. Not quite as good as a fully-eager bottom-up + * mergesort, but it does use 0.2*n fewer comparisons, so is faster in + * the common case that everything fits into L1. + * + * + * The merging is controlled by "count", the number of elements in the + * pending lists. This is beautifully simple code, but rather subtle. + * + * Each time we increment "count", we set one bit (bit k) and clear + * bits k-1 .. 0. Each time this happens (except the very first time + * for each bit, when count increments to 2^k), we merge two lists of + * size 2^k into one list of size 2^(k+1). + * + * This merge happens exactly when the count reaches an odd multiple of + * 2^k, which is when we have 2^k elements pending in smaller lists, + * so it's safe to merge away two lists of size 2^k. + * + * After this happens twice, we have created two lists of size 2^(k+1), + * which will be merged into a list of size 2^(k+2) before we create + * a third list of size 2^(k+1), so there are never more than two pending. + * + * The number of pending lists of size 2^k is determined by the + * state of bit k of "count" plus two extra pieces of information: + * + * - The state of bit k-1 (when k == 0, consider bit -1 always set), and + * - Whether the higher-order bits are zero or non-zero (i.e. + * is count >= 2^(k+1)). + * + * There are six states we distinguish. "x" represents some arbitrary + * bits, and "y" represents some arbitrary non-zero bits: + * 0: 00x: 0 pending of size 2^k; x pending of sizes < 2^k + * 1: 01x: 0 pending of size 2^k; 2^(k-1) + x pending of sizes < 2^k + * 2: x10x: 0 pending of size 2^k; 2^k + x pending of sizes < 2^k + * 3: x11x: 1 pending of size 2^k; 2^(k-1) + x pending of sizes < 2^k + * 4: y00x: 1 pending of size 2^k; 2^k + x pending of sizes < 2^k + * 5: y01x: 2 pending of size 2^k; 2^(k-1) + x pending of sizes < 2^k + * (merge and loop back to state 2) + * + * We gain lists of size 2^k in the 2->3 and 4->5 transitions (because + * bit k-1 is set while the more significant bits are non-zero) and + * merge them away in the 5->2 transition. Note in particular that just + * before the 5->2 transition, all lower-order bits are 11 (state 3), + * so there is one list of each smaller size. + * + * When we reach the end of the input, we merge all the pending + * lists, from smallest to largest. If you work through cases 2 to + * 5 above, you can see that the number of elements we merge with a list + * of size 2^k varies from 2^(k-1) (cases 3 and 5 when x == 0) to + * 2^(k+1) - 1 (second merge of case 5 when x == 2^(k-1) - 1). + */ +__attribute__((nonnull(2,3))) +void list_sort(void *priv, struct list_head *head, list_cmp_func_t cmp) +{ + struct list_head *list = head->next, *pending = NULL; + size_t count = 0; /* Count of pending */ + + if (list == head->prev) /* Zero or one elements */ + return; + + /* Convert to a null-terminated singly-linked list. */ + head->prev->next = NULL; + + /* + * Data structure invariants: + * - All lists are singly linked and null-terminated; prev + * pointers are not maintained. + * - pending is a prev-linked "list of lists" of sorted + * sublists awaiting further merging. + * - Each of the sorted sublists is power-of-two in size. + * - Sublists are sorted by size and age, smallest & newest at front. + * - There are zero to two sublists of each size. + * - A pair of pending sublists are merged as soon as the number + * of following pending elements equals their size (i.e. + * each time count reaches an odd multiple of that size). + * That ensures each later final merge will be at worst 2:1. + * - Each round consists of: + * - Merging the two sublists selected by the highest bit + * which flips when count is incremented, and + * - Adding an element from the input as a size-1 sublist. + */ + do { + size_t bits; + struct list_head **tail = &pending; + + /* Find the least-significant clear bit in count */ + for (bits = count; bits & 1; bits >>= 1) + tail = &(*tail)->prev; + /* Do the indicated merge */ + if (likely(bits)) { + struct list_head *a = *tail, *b = a->prev; + + a = merge(priv, cmp, b, a); + /* Install the merged result in place of the inputs */ + a->prev = b->prev; + *tail = a; + } + + /* Move one element from input list to pending */ + list->prev = pending; + pending = list; + list = list->next; + pending->next = NULL; + count++; + } while (list); + + /* End of input; merge together all the pending lists. */ + list = pending; + pending = pending->prev; + for (;;) { + struct list_head *next = pending->prev; + + if (!next) + break; + list = merge(priv, cmp, pending, list); + pending = next; + } + /* The final merge, rebuilding prev links */ + merge_final(priv, cmp, head, pending, list); +} +EXPORT_SYMBOL(list_sort); -- cgit v1.2.3