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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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+===================
+Block IO Controller
+===================
+
+Overview
+========
+cgroup subsys "blkio" implements the block io controller. There seems to be
+a need of various kinds of IO control policies (like proportional BW, max BW)
+both at leaf nodes as well as at intermediate nodes in a storage hierarchy.
+Plan is to use the same cgroup based management interface for blkio controller
+and based on user options switch IO policies in the background.
+
+One IO control policy is throttling policy which can be used to
+specify upper IO rate limits on devices. This policy is implemented in
+generic block layer and can be used on leaf nodes as well as higher
+level logical devices like device mapper.
+
+HOWTO
+=====
+
+Throttling/Upper Limit policy
+-----------------------------
+Enable Block IO controller::
+
+ CONFIG_BLK_CGROUP=y
+
+Enable throttling in block layer::
+
+ CONFIG_BLK_DEV_THROTTLING=y
+
+Mount blkio controller (see cgroups.txt, Why are cgroups needed?)::
+
+ mount -t cgroup -o blkio none /sys/fs/cgroup/blkio
+
+Specify a bandwidth rate on particular device for root group. The format
+for policy is "<major>:<minor> <bytes_per_second>"::
+
+ echo "8:16 1048576" > /sys/fs/cgroup/blkio/blkio.throttle.read_bps_device
+
+This will put a limit of 1MB/second on reads happening for root group
+on device having major/minor number 8:16.
+
+Run dd to read a file and see if rate is throttled to 1MB/s or not::
+
+ # dd iflag=direct if=/mnt/common/zerofile of=/dev/null bs=4K count=1024
+ 1024+0 records in
+ 1024+0 records out
+ 4194304 bytes (4.2 MB) copied, 4.0001 s, 1.0 MB/s
+
+Limits for writes can be put using blkio.throttle.write_bps_device file.
+
+Hierarchical Cgroups
+====================
+
+Throttling implements hierarchy support; however,
+throttling's hierarchy support is enabled iff "sane_behavior" is
+enabled from cgroup side, which currently is a development option and
+not publicly available.
+
+If somebody created a hierarchy like as follows::
+
+ root
+ / \
+ test1 test2
+ |
+ test3
+
+Throttling with "sane_behavior" will handle the
+hierarchy correctly. For throttling, all limits apply
+to the whole subtree while all statistics are local to the IOs
+directly generated by tasks in that cgroup.
+
+Throttling without "sane_behavior" enabled from cgroup side will
+practically treat all groups at same level as if it looks like the
+following::
+
+ pivot
+ / / \ \
+ root test1 test2 test3
+
+Various user visible config options
+===================================
+
+ CONFIG_BLK_CGROUP
+ Block IO controller.
+
+ CONFIG_BFQ_CGROUP_DEBUG
+ Debug help. Right now some additional stats file show up in cgroup
+ if this option is enabled.
+
+ CONFIG_BLK_DEV_THROTTLING
+ Enable block device throttling support in block layer.
+
+Details of cgroup files
+=======================
+
+Proportional weight policy files
+--------------------------------
+
+ blkio.bfq.weight
+ Specifies per cgroup weight. This is default weight of the group
+ on all the devices until and unless overridden by per device rule
+ (see `blkio.bfq.weight_device` below).
+
+ Currently allowed range of weights is from 1 to 1000. For more details,
+ see Documentation/block/bfq-iosched.rst.
+
+ blkio.bfq.weight_device
+ Specifes per cgroup per device weights, overriding the default group
+ weight. For more details, see Documentation/block/bfq-iosched.rst.
+
+ Following is the format::
+
+ # echo dev_maj:dev_minor weight > blkio.bfq.weight_device
+
+ Configure weight=300 on /dev/sdb (8:16) in this cgroup::
+
+ # echo 8:16 300 > blkio.bfq.weight_device
+ # cat blkio.bfq.weight_device
+ dev weight
+ 8:16 300
+
+ Configure weight=500 on /dev/sda (8:0) in this cgroup::
+
+ # echo 8:0 500 > blkio.bfq.weight_device
+ # cat blkio.bfq.weight_device
+ dev weight
+ 8:0 500
+ 8:16 300
+
+ Remove specific weight for /dev/sda in this cgroup::
+
+ # echo 8:0 0 > blkio.bfq.weight_device
+ # cat blkio.bfq.weight_device
+ dev weight
+ 8:16 300
+
+ blkio.time
+ Disk time allocated to cgroup per device in milliseconds. First
+ two fields specify the major and minor number of the device and
+ third field specifies the disk time allocated to group in
+ milliseconds.
+
+ blkio.sectors
+ Number of sectors transferred to/from disk by the group. First
+ two fields specify the major and minor number of the device and
+ third field specifies the number of sectors transferred by the
+ group to/from the device.
+
+ blkio.io_service_bytes
+ Number of bytes transferred to/from the disk by the group. These
+ are further divided by the type of operation - read or write, sync
+ or async. First two fields specify the major and minor number of the
+ device, third field specifies the operation type and the fourth field
+ specifies the number of bytes.
+
+ blkio.io_serviced
+ Number of IOs (bio) issued to the disk by the group. These
+ are further divided by the type of operation - read or write, sync
+ or async. First two fields specify the major and minor number of the
+ device, third field specifies the operation type and the fourth field
+ specifies the number of IOs.
+
+ blkio.io_service_time
+ Total amount of time between request dispatch and request completion
+ for the IOs done by this cgroup. This is in nanoseconds to make it
+ meaningful for flash devices too. For devices with queue depth of 1,
+ this time represents the actual service time. When queue_depth > 1,
+ that is no longer true as requests may be served out of order. This
+ may cause the service time for a given IO to include the service time
+ of multiple IOs when served out of order which may result in total
+ io_service_time > actual time elapsed. This time is further divided by
+ the type of operation - read or write, sync or async. First two fields
+ specify the major and minor number of the device, third field
+ specifies the operation type and the fourth field specifies the
+ io_service_time in ns.
+
+ blkio.io_wait_time
+ Total amount of time the IOs for this cgroup spent waiting in the
+ scheduler queues for service. This can be greater than the total time
+ elapsed since it is cumulative io_wait_time for all IOs. It is not a
+ measure of total time the cgroup spent waiting but rather a measure of
+ the wait_time for its individual IOs. For devices with queue_depth > 1
+ this metric does not include the time spent waiting for service once
+ the IO is dispatched to the device but till it actually gets serviced
+ (there might be a time lag here due to re-ordering of requests by the
+ device). This is in nanoseconds to make it meaningful for flash
+ devices too. This time is further divided by the type of operation -
+ read or write, sync or async. First two fields specify the major and
+ minor number of the device, third field specifies the operation type
+ and the fourth field specifies the io_wait_time in ns.
+
+ blkio.io_merged
+ Total number of bios/requests merged into requests belonging to this
+ cgroup. This is further divided by the type of operation - read or
+ write, sync or async.
+
+ blkio.io_queued
+ Total number of requests queued up at any given instant for this
+ cgroup. This is further divided by the type of operation - read or
+ write, sync or async.
+
+ blkio.avg_queue_size
+ Debugging aid only enabled if CONFIG_BFQ_CGROUP_DEBUG=y.
+ The average queue size for this cgroup over the entire time of this
+ cgroup's existence. Queue size samples are taken each time one of the
+ queues of this cgroup gets a timeslice.
+
+ blkio.group_wait_time
+ Debugging aid only enabled if CONFIG_BFQ_CGROUP_DEBUG=y.
+ This is the amount of time the cgroup had to wait since it became busy
+ (i.e., went from 0 to 1 request queued) to get a timeslice for one of
+ its queues. This is different from the io_wait_time which is the
+ cumulative total of the amount of time spent by each IO in that cgroup
+ waiting in the scheduler queue. This is in nanoseconds. If this is
+ read when the cgroup is in a waiting (for timeslice) state, the stat
+ will only report the group_wait_time accumulated till the last time it
+ got a timeslice and will not include the current delta.
+
+ blkio.empty_time
+ Debugging aid only enabled if CONFIG_BFQ_CGROUP_DEBUG=y.
+ This is the amount of time a cgroup spends without any pending
+ requests when not being served, i.e., it does not include any time
+ spent idling for one of the queues of the cgroup. This is in
+ nanoseconds. If this is read when the cgroup is in an empty state,
+ the stat will only report the empty_time accumulated till the last
+ time it had a pending request and will not include the current delta.
+
+ blkio.idle_time
+ Debugging aid only enabled if CONFIG_BFQ_CGROUP_DEBUG=y.
+ This is the amount of time spent by the IO scheduler idling for a
+ given cgroup in anticipation of a better request than the existing ones
+ from other queues/cgroups. This is in nanoseconds. If this is read
+ when the cgroup is in an idling state, the stat will only report the
+ idle_time accumulated till the last idle period and will not include
+ the current delta.
+
+ blkio.dequeue
+ Debugging aid only enabled if CONFIG_BFQ_CGROUP_DEBUG=y. This
+ gives the statistics about how many a times a group was dequeued
+ from service tree of the device. First two fields specify the major
+ and minor number of the device and third field specifies the number
+ of times a group was dequeued from a particular device.
+
+ blkio.*_recursive
+ Recursive version of various stats. These files show the
+ same information as their non-recursive counterparts but
+ include stats from all the descendant cgroups.
+
+Throttling/Upper limit policy files
+-----------------------------------
+ blkio.throttle.read_bps_device
+ Specifies upper limit on READ rate from the device. IO rate is
+ specified in bytes per second. Rules are per device. Following is
+ the format::
+
+ echo "<major>:<minor> <rate_bytes_per_second>" > /cgrp/blkio.throttle.read_bps_device
+
+ blkio.throttle.write_bps_device
+ Specifies upper limit on WRITE rate to the device. IO rate is
+ specified in bytes per second. Rules are per device. Following is
+ the format::
+
+ echo "<major>:<minor> <rate_bytes_per_second>" > /cgrp/blkio.throttle.write_bps_device
+
+ blkio.throttle.read_iops_device
+ Specifies upper limit on READ rate from the device. IO rate is
+ specified in IO per second. Rules are per device. Following is
+ the format::
+
+ echo "<major>:<minor> <rate_io_per_second>" > /cgrp/blkio.throttle.read_iops_device
+
+ blkio.throttle.write_iops_device
+ Specifies upper limit on WRITE rate to the device. IO rate is
+ specified in io per second. Rules are per device. Following is
+ the format::
+
+ echo "<major>:<minor> <rate_io_per_second>" > /cgrp/blkio.throttle.write_iops_device
+
+ Note: If both BW and IOPS rules are specified for a device, then IO is
+ subjected to both the constraints.
+
+ blkio.throttle.io_serviced
+ Number of IOs (bio) issued to the disk by the group. These
+ are further divided by the type of operation - read or write, sync
+ or async. First two fields specify the major and minor number of the
+ device, third field specifies the operation type and the fourth field
+ specifies the number of IOs.
+
+ blkio.throttle.io_service_bytes
+ Number of bytes transferred to/from the disk by the group. These
+ are further divided by the type of operation - read or write, sync
+ or async. First two fields specify the major and minor number of the
+ device, third field specifies the operation type and the fourth field
+ specifies the number of bytes.
+
+Common files among various policies
+-----------------------------------
+ blkio.reset_stats
+ Writing an int to this file will result in resetting all the stats
+ for that cgroup.