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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
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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(). ...
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+===================
+Block io priorities
+===================
+
+
+Intro
+-----
+
+With the introduction of cfq v3 (aka cfq-ts or time sliced cfq), basic io
+priorities are supported for reads on files. This enables users to io nice
+processes or process groups, similar to what has been possible with cpu
+scheduling for ages. This document mainly details the current possibilities
+with cfq; other io schedulers do not support io priorities thus far.
+
+Scheduling classes
+------------------
+
+CFQ implements three generic scheduling classes that determine how io is
+served for a process.
+
+IOPRIO_CLASS_RT: This is the realtime io class. This scheduling class is given
+higher priority than any other in the system, processes from this class are
+given first access to the disk every time. Thus it needs to be used with some
+care, one io RT process can starve the entire system. Within the RT class,
+there are 8 levels of class data that determine exactly how much time this
+process needs the disk for on each service. In the future this might change
+to be more directly mappable to performance, by passing in a wanted data
+rate instead.
+
+IOPRIO_CLASS_BE: This is the best-effort scheduling class, which is the default
+for any process that hasn't set a specific io priority. The class data
+determines how much io bandwidth the process will get, it's directly mappable
+to the cpu nice levels just more coarsely implemented. 0 is the highest
+BE prio level, 7 is the lowest. The mapping between cpu nice level and io
+nice level is determined as: io_nice = (cpu_nice + 20) / 5.
+
+IOPRIO_CLASS_IDLE: This is the idle scheduling class, processes running at this
+level only get io time when no one else needs the disk. The idle class has no
+class data, since it doesn't really apply here.
+
+Tools
+-----
+
+See below for a sample ionice tool. Usage::
+
+ # ionice -c<class> -n<level> -p<pid>
+
+If pid isn't given, the current process is assumed. IO priority settings
+are inherited on fork, so you can use ionice to start the process at a given
+level::
+
+ # ionice -c2 -n0 /bin/ls
+
+will run ls at the best-effort scheduling class at the highest priority.
+For a running process, you can give the pid instead::
+
+ # ionice -c1 -n2 -p100
+
+will change pid 100 to run at the realtime scheduling class, at priority 2.
+
+ionice.c tool::
+
+ #include <stdio.h>
+ #include <stdlib.h>
+ #include <errno.h>
+ #include <getopt.h>
+ #include <unistd.h>
+ #include <sys/ptrace.h>
+ #include <asm/unistd.h>
+
+ extern int sys_ioprio_set(int, int, int);
+ extern int sys_ioprio_get(int, int);
+
+ #if defined(__i386__)
+ #define __NR_ioprio_set 289
+ #define __NR_ioprio_get 290
+ #elif defined(__ppc__)
+ #define __NR_ioprio_set 273
+ #define __NR_ioprio_get 274
+ #elif defined(__x86_64__)
+ #define __NR_ioprio_set 251
+ #define __NR_ioprio_get 252
+ #elif defined(__ia64__)
+ #define __NR_ioprio_set 1274
+ #define __NR_ioprio_get 1275
+ #else
+ #error "Unsupported arch"
+ #endif
+
+ static inline int ioprio_set(int which, int who, int ioprio)
+ {
+ return syscall(__NR_ioprio_set, which, who, ioprio);
+ }
+
+ static inline int ioprio_get(int which, int who)
+ {
+ return syscall(__NR_ioprio_get, which, who);
+ }
+
+ enum {
+ IOPRIO_CLASS_NONE,
+ IOPRIO_CLASS_RT,
+ IOPRIO_CLASS_BE,
+ IOPRIO_CLASS_IDLE,
+ };
+
+ enum {
+ IOPRIO_WHO_PROCESS = 1,
+ IOPRIO_WHO_PGRP,
+ IOPRIO_WHO_USER,
+ };
+
+ #define IOPRIO_CLASS_SHIFT 13
+
+ const char *to_prio[] = { "none", "realtime", "best-effort", "idle", };
+
+ int main(int argc, char *argv[])
+ {
+ int ioprio = 4, set = 0, ioprio_class = IOPRIO_CLASS_BE;
+ int c, pid = 0;
+
+ while ((c = getopt(argc, argv, "+n:c:p:")) != EOF) {
+ switch (c) {
+ case 'n':
+ ioprio = strtol(optarg, NULL, 10);
+ set = 1;
+ break;
+ case 'c':
+ ioprio_class = strtol(optarg, NULL, 10);
+ set = 1;
+ break;
+ case 'p':
+ pid = strtol(optarg, NULL, 10);
+ break;
+ }
+ }
+
+ switch (ioprio_class) {
+ case IOPRIO_CLASS_NONE:
+ ioprio_class = IOPRIO_CLASS_BE;
+ break;
+ case IOPRIO_CLASS_RT:
+ case IOPRIO_CLASS_BE:
+ break;
+ case IOPRIO_CLASS_IDLE:
+ ioprio = 7;
+ break;
+ default:
+ printf("bad prio class %d\n", ioprio_class);
+ return 1;
+ }
+
+ if (!set) {
+ if (!pid && argv[optind])
+ pid = strtol(argv[optind], NULL, 10);
+
+ ioprio = ioprio_get(IOPRIO_WHO_PROCESS, pid);
+
+ printf("pid=%d, %d\n", pid, ioprio);
+
+ if (ioprio == -1)
+ perror("ioprio_get");
+ else {
+ ioprio_class = ioprio >> IOPRIO_CLASS_SHIFT;
+ ioprio = ioprio & 0xff;
+ printf("%s: prio %d\n", to_prio[ioprio_class], ioprio);
+ }
+ } else {
+ if (ioprio_set(IOPRIO_WHO_PROCESS, pid, ioprio | ioprio_class << IOPRIO_CLASS_SHIFT) == -1) {
+ perror("ioprio_set");
+ return 1;
+ }
+
+ if (argv[optind])
+ execvp(argv[optind], &argv[optind]);
+ }
+
+ return 0;
+ }
+
+
+March 11 2005, Jens Axboe <jens.axboe@oracle.com>