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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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+=====================
+I/O statistics fields
+=====================
+
+Since 2.4.20 (and some versions before, with patches), and 2.5.45,
+more extensive disk statistics have been introduced to help measure disk
+activity. Tools such as ``sar`` and ``iostat`` typically interpret these and do
+the work for you, but in case you are interested in creating your own
+tools, the fields are explained here.
+
+In 2.4 now, the information is found as additional fields in
+``/proc/partitions``. In 2.6 and upper, the same information is found in two
+places: one is in the file ``/proc/diskstats``, and the other is within
+the sysfs file system, which must be mounted in order to obtain
+the information. Throughout this document we'll assume that sysfs
+is mounted on ``/sys``, although of course it may be mounted anywhere.
+Both ``/proc/diskstats`` and sysfs use the same source for the information
+and so should not differ.
+
+Here are examples of these different formats::
+
+ 2.4:
+ 3 0 39082680 hda 446216 784926 9550688 4382310 424847 312726 5922052 19310380 0 3376340 23705160
+ 3 1 9221278 hda1 35486 0 35496 38030 0 0 0 0 0 38030 38030
+
+ 2.6+ sysfs:
+ 446216 784926 9550688 4382310 424847 312726 5922052 19310380 0 3376340 23705160
+ 35486 38030 38030 38030
+
+ 2.6+ diskstats:
+ 3 0 hda 446216 784926 9550688 4382310 424847 312726 5922052 19310380 0 3376340 23705160
+ 3 1 hda1 35486 38030 38030 38030
+
+ 4.18+ diskstats:
+ 3 0 hda 446216 784926 9550688 4382310 424847 312726 5922052 19310380 0 3376340 23705160 0 0 0 0
+
+On 2.4 you might execute ``grep 'hda ' /proc/partitions``. On 2.6+, you have
+a choice of ``cat /sys/block/hda/stat`` or ``grep 'hda ' /proc/diskstats``.
+
+The advantage of one over the other is that the sysfs choice works well
+if you are watching a known, small set of disks. ``/proc/diskstats`` may
+be a better choice if you are watching a large number of disks because
+you'll avoid the overhead of 50, 100, or 500 or more opens/closes with
+each snapshot of your disk statistics.
+
+In 2.4, the statistics fields are those after the device name. In
+the above example, the first field of statistics would be 446216.
+By contrast, in 2.6+ if you look at ``/sys/block/hda/stat``, you'll
+find just the 15 fields, beginning with 446216. If you look at
+``/proc/diskstats``, the 15 fields will be preceded by the major and
+minor device numbers, and device name. Each of these formats provides
+15 fields of statistics, each meaning exactly the same things.
+All fields except field 9 are cumulative since boot. Field 9 should
+go to zero as I/Os complete; all others only increase (unless they
+overflow and wrap). Wrapping might eventually occur on a very busy
+or long-lived system; so applications should be prepared to deal with
+it. Regarding wrapping, the types of the fields are either unsigned
+int (32 bit) or unsigned long (32-bit or 64-bit, depending on your
+machine) as noted per-field below. Unless your observations are very
+spread in time, these fields should not wrap twice before you notice it.
+
+Each set of stats only applies to the indicated device; if you want
+system-wide stats you'll have to find all the devices and sum them all up.
+
+Field 1 -- # of reads completed (unsigned long)
+ This is the total number of reads completed successfully.
+
+Field 2 -- # of reads merged, field 6 -- # of writes merged (unsigned long)
+ Reads and writes which are adjacent to each other may be merged for
+ efficiency. Thus two 4K reads may become one 8K read before it is
+ ultimately handed to the disk, and so it will be counted (and queued)
+ as only one I/O. This field lets you know how often this was done.
+
+Field 3 -- # of sectors read (unsigned long)
+ This is the total number of sectors read successfully.
+
+Field 4 -- # of milliseconds spent reading (unsigned int)
+ This is the total number of milliseconds spent by all reads (as
+ measured from blk_mq_alloc_request() to __blk_mq_end_request()).
+
+Field 5 -- # of writes completed (unsigned long)
+ This is the total number of writes completed successfully.
+
+Field 6 -- # of writes merged (unsigned long)
+ See the description of field 2.
+
+Field 7 -- # of sectors written (unsigned long)
+ This is the total number of sectors written successfully.
+
+Field 8 -- # of milliseconds spent writing (unsigned int)
+ This is the total number of milliseconds spent by all writes (as
+ measured from blk_mq_alloc_request() to __blk_mq_end_request()).
+
+Field 9 -- # of I/Os currently in progress (unsigned int)
+ The only field that should go to zero. Incremented as requests are
+ given to appropriate struct request_queue and decremented as they finish.
+
+Field 10 -- # of milliseconds spent doing I/Os (unsigned int)
+ This field increases so long as field 9 is nonzero.
+
+ Since 5.0 this field counts jiffies when at least one request was
+ started or completed. If request runs more than 2 jiffies then some
+ I/O time might be not accounted in case of concurrent requests.
+
+Field 11 -- weighted # of milliseconds spent doing I/Os (unsigned int)
+ This field is incremented at each I/O start, I/O completion, I/O
+ merge, or read of these stats by the number of I/Os in progress
+ (field 9) times the number of milliseconds spent doing I/O since the
+ last update of this field. This can provide an easy measure of both
+ I/O completion time and the backlog that may be accumulating.
+
+Field 12 -- # of discards completed (unsigned long)
+ This is the total number of discards completed successfully.
+
+Field 13 -- # of discards merged (unsigned long)
+ See the description of field 2
+
+Field 14 -- # of sectors discarded (unsigned long)
+ This is the total number of sectors discarded successfully.
+
+Field 15 -- # of milliseconds spent discarding (unsigned int)
+ This is the total number of milliseconds spent by all discards (as
+ measured from blk_mq_alloc_request() to __blk_mq_end_request()).
+
+Field 16 -- # of flush requests completed
+ This is the total number of flush requests completed successfully.
+
+ Block layer combines flush requests and executes at most one at a time.
+ This counts flush requests executed by disk. Not tracked for partitions.
+
+Field 17 -- # of milliseconds spent flushing
+ This is the total number of milliseconds spent by all flush requests.
+
+To avoid introducing performance bottlenecks, no locks are held while
+modifying these counters. This implies that minor inaccuracies may be
+introduced when changes collide, so (for instance) adding up all the
+read I/Os issued per partition should equal those made to the disks ...
+but due to the lack of locking it may only be very close.
+
+In 2.6+, there are counters for each CPU, which make the lack of locking
+almost a non-issue. When the statistics are read, the per-CPU counters
+are summed (possibly overflowing the unsigned long variable they are
+summed to) and the result given to the user. There is no convenient
+user interface for accessing the per-CPU counters themselves.
+
+Since 4.19 request times are measured with nanoseconds precision and
+truncated to milliseconds before showing in this interface.
+
+Disks vs Partitions
+-------------------
+
+There were significant changes between 2.4 and 2.6+ in the I/O subsystem.
+As a result, some statistic information disappeared. The translation from
+a disk address relative to a partition to the disk address relative to
+the host disk happens much earlier. All merges and timings now happen
+at the disk level rather than at both the disk and partition level as
+in 2.4. Consequently, you'll see a different statistics output on 2.6+ for
+partitions from that for disks. There are only *four* fields available
+for partitions on 2.6+ machines. This is reflected in the examples above.
+
+Field 1 -- # of reads issued
+ This is the total number of reads issued to this partition.
+
+Field 2 -- # of sectors read
+ This is the total number of sectors requested to be read from this
+ partition.
+
+Field 3 -- # of writes issued
+ This is the total number of writes issued to this partition.
+
+Field 4 -- # of sectors written
+ This is the total number of sectors requested to be written to
+ this partition.
+
+Note that since the address is translated to a disk-relative one, and no
+record of the partition-relative address is kept, the subsequent success
+or failure of the read cannot be attributed to the partition. In other
+words, the number of reads for partitions is counted slightly before time
+of queuing for partitions, and at completion for whole disks. This is
+a subtle distinction that is probably uninteresting for most cases.
+
+More significant is the error induced by counting the numbers of
+reads/writes before merges for partitions and after for disks. Since a
+typical workload usually contains a lot of successive and adjacent requests,
+the number of reads/writes issued can be several times higher than the
+number of reads/writes completed.
+
+In 2.6.25, the full statistic set is again available for partitions and
+disk and partition statistics are consistent again. Since we still don't
+keep record of the partition-relative address, an operation is attributed to
+the partition which contains the first sector of the request after the
+eventual merges. As requests can be merged across partition, this could lead
+to some (probably insignificant) inaccuracy.
+
+Additional notes
+----------------
+
+In 2.6+, sysfs is not mounted by default. If your distribution of
+Linux hasn't added it already, here's the line you'll want to add to
+your ``/etc/fstab``::
+
+ none /sys sysfs defaults 0 0
+
+
+In 2.6+, all disk statistics were removed from ``/proc/stat``. In 2.4, they
+appear in both ``/proc/partitions`` and ``/proc/stat``, although the ones in
+``/proc/stat`` take a very different format from those in ``/proc/partitions``
+(see proc(5), if your system has it.)
+
+-- ricklind@us.ibm.com