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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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+ktime accessors
+===============
+
+Device drivers can read the current time using ktime_get() and the many
+related functions declared in linux/timekeeping.h. As a rule of thumb,
+using an accessor with a shorter name is preferred over one with a longer
+name if both are equally fit for a particular use case.
+
+Basic ktime_t based interfaces
+------------------------------
+
+The recommended simplest form returns an opaque ktime_t, with variants
+that return time for different clock references:
+
+
+.. c:function:: ktime_t ktime_get( void )
+
+ CLOCK_MONOTONIC
+
+ Useful for reliable timestamps and measuring short time intervals
+ accurately. Starts at system boot time but stops during suspend.
+
+.. c:function:: ktime_t ktime_get_boottime( void )
+
+ CLOCK_BOOTTIME
+
+ Like ktime_get(), but does not stop when suspended. This can be
+ used e.g. for key expiration times that need to be synchronized
+ with other machines across a suspend operation.
+
+.. c:function:: ktime_t ktime_get_real( void )
+
+ CLOCK_REALTIME
+
+ Returns the time in relative to the UNIX epoch starting in 1970
+ using the Coordinated Universal Time (UTC), same as gettimeofday()
+ user space. This is used for all timestamps that need to
+ persist across a reboot, like inode times, but should be avoided
+ for internal uses, since it can jump backwards due to a leap
+ second update, NTP adjustment settimeofday() operation from user
+ space.
+
+.. c:function:: ktime_t ktime_get_clocktai( void )
+
+ CLOCK_TAI
+
+ Like ktime_get_real(), but uses the International Atomic Time (TAI)
+ reference instead of UTC to avoid jumping on leap second updates.
+ This is rarely useful in the kernel.
+
+.. c:function:: ktime_t ktime_get_raw( void )
+
+ CLOCK_MONOTONIC_RAW
+
+ Like ktime_get(), but runs at the same rate as the hardware
+ clocksource without (NTP) adjustments for clock drift. This is
+ also rarely needed in the kernel.
+
+nanosecond, timespec64, and second output
+-----------------------------------------
+
+For all of the above, there are variants that return the time in a
+different format depending on what is required by the user:
+
+.. c:function:: u64 ktime_get_ns( void )
+ u64 ktime_get_boottime_ns( void )
+ u64 ktime_get_real_ns( void )
+ u64 ktime_get_clocktai_ns( void )
+ u64 ktime_get_raw_ns( void )
+
+ Same as the plain ktime_get functions, but returning a u64 number
+ of nanoseconds in the respective time reference, which may be
+ more convenient for some callers.
+
+.. c:function:: void ktime_get_ts64( struct timespec64 * )
+ void ktime_get_boottime_ts64( struct timespec64 * )
+ void ktime_get_real_ts64( struct timespec64 * )
+ void ktime_get_clocktai_ts64( struct timespec64 * )
+ void ktime_get_raw_ts64( struct timespec64 * )
+
+ Same above, but returns the time in a 'struct timespec64', split
+ into seconds and nanoseconds. This can avoid an extra division
+ when printing the time, or when passing it into an external
+ interface that expects a 'timespec' or 'timeval' structure.
+
+.. c:function:: time64_t ktime_get_seconds( void )
+ time64_t ktime_get_boottime_seconds( void )
+ time64_t ktime_get_real_seconds( void )
+ time64_t ktime_get_clocktai_seconds( void )
+ time64_t ktime_get_raw_seconds( void )
+
+ Return a coarse-grained version of the time as a scalar
+ time64_t. This avoids accessing the clock hardware and rounds
+ down the seconds to the full seconds of the last timer tick
+ using the respective reference.
+
+Coarse and fast_ns access
+-------------------------
+
+Some additional variants exist for more specialized cases:
+
+.. c:function:: ktime_t ktime_get_coarse( void )
+ ktime_t ktime_get_coarse_boottime( void )
+ ktime_t ktime_get_coarse_real( void )
+ ktime_t ktime_get_coarse_clocktai( void )
+
+.. c:function:: u64 ktime_get_coarse_ns( void )
+ u64 ktime_get_coarse_boottime_ns( void )
+ u64 ktime_get_coarse_real_ns( void )
+ u64 ktime_get_coarse_clocktai_ns( void )
+
+.. c:function:: void ktime_get_coarse_ts64( struct timespec64 * )
+ void ktime_get_coarse_boottime_ts64( struct timespec64 * )
+ void ktime_get_coarse_real_ts64( struct timespec64 * )
+ void ktime_get_coarse_clocktai_ts64( struct timespec64 * )
+
+ These are quicker than the non-coarse versions, but less accurate,
+ corresponding to CLOCK_MONOTONIC_COARSE and CLOCK_REALTIME_COARSE
+ in user space, along with the equivalent boottime/tai/raw
+ timebase not available in user space.
+
+ The time returned here corresponds to the last timer tick, which
+ may be as much as 10ms in the past (for CONFIG_HZ=100), same as
+ reading the 'jiffies' variable. These are only useful when called
+ in a fast path and one still expects better than second accuracy,
+ but can't easily use 'jiffies', e.g. for inode timestamps.
+ Skipping the hardware clock access saves around 100 CPU cycles
+ on most modern machines with a reliable cycle counter, but
+ up to several microseconds on older hardware with an external
+ clocksource.
+
+.. c:function:: u64 ktime_get_mono_fast_ns( void )
+ u64 ktime_get_raw_fast_ns( void )
+ u64 ktime_get_boot_fast_ns( void )
+ u64 ktime_get_tai_fast_ns( void )
+ u64 ktime_get_real_fast_ns( void )
+
+ These variants are safe to call from any context, including from
+ a non-maskable interrupt (NMI) during a timekeeper update, and
+ while we are entering suspend with the clocksource powered down.
+ This is useful in some tracing or debugging code as well as
+ machine check reporting, but most drivers should never call them,
+ since the time is allowed to jump under certain conditions.
+
+Deprecated time interfaces
+--------------------------
+
+Older kernels used some other interfaces that are now being phased out
+but may appear in third-party drivers being ported here. In particular,
+all interfaces returning a 'struct timeval' or 'struct timespec' have
+been replaced because the tv_sec member overflows in year 2038 on 32-bit
+architectures. These are the recommended replacements:
+
+.. c:function:: void ktime_get_ts( struct timespec * )
+
+ Use ktime_get() or ktime_get_ts64() instead.
+
+.. c:function:: void do_gettimeofday( struct timeval * )
+ void getnstimeofday( struct timespec * )
+ void getnstimeofday64( struct timespec64 * )
+ void ktime_get_real_ts( struct timespec * )
+
+ ktime_get_real_ts64() is a direct replacement, but consider using
+ monotonic time (ktime_get_ts64()) and/or a ktime_t based interface
+ (ktime_get()/ktime_get_real()).
+
+.. c:function:: struct timespec current_kernel_time( void )
+ struct timespec64 current_kernel_time64( void )
+ struct timespec get_monotonic_coarse( void )
+ struct timespec64 get_monotonic_coarse64( void )
+
+ These are replaced by ktime_get_coarse_real_ts64() and
+ ktime_get_coarse_ts64(). However, A lot of code that wants
+ coarse-grained times can use the simple 'jiffies' instead, while
+ some drivers may actually want the higher resolution accessors
+ these days.
+
+.. c:function:: struct timespec getrawmonotonic( void )
+ struct timespec64 getrawmonotonic64( void )
+ struct timespec timekeeping_clocktai( void )
+ struct timespec64 timekeeping_clocktai64( void )
+ struct timespec get_monotonic_boottime( void )
+ struct timespec64 get_monotonic_boottime64( void )
+
+ These are replaced by ktime_get_raw()/ktime_get_raw_ts64(),
+ ktime_get_clocktai()/ktime_get_clocktai_ts64() as well
+ as ktime_get_boottime()/ktime_get_boottime_ts64().
+ However, if the particular choice of clock source is not
+ important for the user, consider converting to
+ ktime_get()/ktime_get_ts64() instead for consistency.