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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)
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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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+=============
+DM statistics
+=============
+
+Device Mapper supports the collection of I/O statistics on user-defined
+regions of a DM device. If no regions are defined no statistics are
+collected so there isn't any performance impact. Only bio-based DM
+devices are currently supported.
+
+Each user-defined region specifies a starting sector, length and step.
+Individual statistics will be collected for each step-sized area within
+the range specified.
+
+The I/O statistics counters for each step-sized area of a region are
+in the same format as `/sys/block/*/stat` or `/proc/diskstats` (see:
+Documentation/admin-guide/iostats.rst). But two extra counters (12 and 13) are
+provided: total time spent reading and writing. When the histogram
+argument is used, the 14th parameter is reported that represents the
+histogram of latencies. All these counters may be accessed by sending
+the @stats_print message to the appropriate DM device via dmsetup.
+
+The reported times are in milliseconds and the granularity depends on
+the kernel ticks. When the option precise_timestamps is used, the
+reported times are in nanoseconds.
+
+Each region has a corresponding unique identifier, which we call a
+region_id, that is assigned when the region is created. The region_id
+must be supplied when querying statistics about the region, deleting the
+region, etc. Unique region_ids enable multiple userspace programs to
+request and process statistics for the same DM device without stepping
+on each other's data.
+
+The creation of DM statistics will allocate memory via kmalloc or
+fallback to using vmalloc space. At most, 1/4 of the overall system
+memory may be allocated by DM statistics. The admin can see how much
+memory is used by reading:
+
+ /sys/module/dm_mod/parameters/stats_current_allocated_bytes
+
+Messages
+========
+
+ @stats_create <range> <step> [<number_of_optional_arguments> <optional_arguments>...] [<program_id> [<aux_data>]]
+ Create a new region and return the region_id.
+
+ <range>
+ "-"
+ whole device
+ "<start_sector>+<length>"
+ a range of <length> 512-byte sectors
+ starting with <start_sector>.
+
+ <step>
+ "<area_size>"
+ the range is subdivided into areas each containing
+ <area_size> sectors.
+ "/<number_of_areas>"
+ the range is subdivided into the specified
+ number of areas.
+
+ <number_of_optional_arguments>
+ The number of optional arguments
+
+ <optional_arguments>
+ The following optional arguments are supported:
+
+ precise_timestamps
+ use precise timer with nanosecond resolution
+ instead of the "jiffies" variable. When this argument is
+ used, the resulting times are in nanoseconds instead of
+ milliseconds. Precise timestamps are a little bit slower
+ to obtain than jiffies-based timestamps.
+ histogram:n1,n2,n3,n4,...
+ collect histogram of latencies. The
+ numbers n1, n2, etc are times that represent the boundaries
+ of the histogram. If precise_timestamps is not used, the
+ times are in milliseconds, otherwise they are in
+ nanoseconds. For each range, the kernel will report the
+ number of requests that completed within this range. For
+ example, if we use "histogram:10,20,30", the kernel will
+ report four numbers a:b:c:d. a is the number of requests
+ that took 0-10 ms to complete, b is the number of requests
+ that took 10-20 ms to complete, c is the number of requests
+ that took 20-30 ms to complete and d is the number of
+ requests that took more than 30 ms to complete.
+
+ <program_id>
+ An optional parameter. A name that uniquely identifies
+ the userspace owner of the range. This groups ranges together
+ so that userspace programs can identify the ranges they
+ created and ignore those created by others.
+ The kernel returns this string back in the output of
+ @stats_list message, but it doesn't use it for anything else.
+ If we omit the number of optional arguments, program id must not
+ be a number, otherwise it would be interpreted as the number of
+ optional arguments.
+
+ <aux_data>
+ An optional parameter. A word that provides auxiliary data
+ that is useful to the client program that created the range.
+ The kernel returns this string back in the output of
+ @stats_list message, but it doesn't use this value for anything.
+
+ @stats_delete <region_id>
+ Delete the region with the specified id.
+
+ <region_id>
+ region_id returned from @stats_create
+
+ @stats_clear <region_id>
+ Clear all the counters except the in-flight i/o counters.
+
+ <region_id>
+ region_id returned from @stats_create
+
+ @stats_list [<program_id>]
+ List all regions registered with @stats_create.
+
+ <program_id>
+ An optional parameter.
+ If this parameter is specified, only matching regions
+ are returned.
+ If it is not specified, all regions are returned.
+
+ Output format:
+ <region_id>: <start_sector>+<length> <step> <program_id> <aux_data>
+ precise_timestamps histogram:n1,n2,n3,...
+
+ The strings "precise_timestamps" and "histogram" are printed only
+ if they were specified when creating the region.
+
+ @stats_print <region_id> [<starting_line> <number_of_lines>]
+ Print counters for each step-sized area of a region.
+
+ <region_id>
+ region_id returned from @stats_create
+
+ <starting_line>
+ The index of the starting line in the output.
+ If omitted, all lines are returned.
+
+ <number_of_lines>
+ The number of lines to include in the output.
+ If omitted, all lines are returned.
+
+ Output format for each step-sized area of a region:
+
+ <start_sector>+<length>
+ counters
+
+ The first 11 counters have the same meaning as
+ `/sys/block/*/stat or /proc/diskstats`.
+
+ Please refer to Documentation/admin-guide/iostats.rst for details.
+
+ 1. the number of reads completed
+ 2. the number of reads merged
+ 3. the number of sectors read
+ 4. the number of milliseconds spent reading
+ 5. the number of writes completed
+ 6. the number of writes merged
+ 7. the number of sectors written
+ 8. the number of milliseconds spent writing
+ 9. the number of I/Os currently in progress
+ 10. the number of milliseconds spent doing I/Os
+ 11. the weighted number of milliseconds spent doing I/Os
+
+ Additional counters:
+
+ 12. the total time spent reading in milliseconds
+ 13. the total time spent writing in milliseconds
+
+ @stats_print_clear <region_id> [<starting_line> <number_of_lines>]
+ Atomically print and then clear all the counters except the
+ in-flight i/o counters. Useful when the client consuming the
+ statistics does not want to lose any statistics (those updated
+ between printing and clearing).
+
+ <region_id>
+ region_id returned from @stats_create
+
+ <starting_line>
+ The index of the starting line in the output.
+ If omitted, all lines are printed and then cleared.
+
+ <number_of_lines>
+ The number of lines to process.
+ If omitted, all lines are printed and then cleared.
+
+ @stats_set_aux <region_id> <aux_data>
+ Store auxiliary data aux_data for the specified region.
+
+ <region_id>
+ region_id returned from @stats_create
+
+ <aux_data>
+ The string that identifies data which is useful to the client
+ program that created the range. The kernel returns this
+ string back in the output of @stats_list message, but it
+ doesn't use this value for anything.
+
+Examples
+========
+
+Subdivide the DM device 'vol' into 100 pieces and start collecting
+statistics on them::
+
+ dmsetup message vol 0 @stats_create - /100
+
+Set the auxiliary data string to "foo bar baz" (the escape for each
+space must also be escaped, otherwise the shell will consume them)::
+
+ dmsetup message vol 0 @stats_set_aux 0 foo\\ bar\\ baz
+
+List the statistics::
+
+ dmsetup message vol 0 @stats_list
+
+Print the statistics::
+
+ dmsetup message vol 0 @stats_print 0
+
+Delete the statistics::
+
+ dmsetup message vol 0 @stats_delete 0