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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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+.. _clangformat:
+
+clang-format
+============
+
+``clang-format`` is a tool to format C/C++/... code according to
+a set of rules and heuristics. Like most tools, it is not perfect
+nor covers every single case, but it is good enough to be helpful.
+
+``clang-format`` can be used for several purposes:
+
+ - Quickly reformat a block of code to the kernel style. Specially useful
+ when moving code around and aligning/sorting. See clangformatreformat_.
+
+ - Spot style mistakes, typos and possible improvements in files
+ you maintain, patches you review, diffs, etc. See clangformatreview_.
+
+ - Help you follow the coding style rules, specially useful for those
+ new to kernel development or working at the same time in several
+ projects with different coding styles.
+
+Its configuration file is ``.clang-format`` in the root of the kernel tree.
+The rules contained there try to approximate the most common kernel
+coding style. They also try to follow :ref:`Documentation/process/coding-style.rst <codingstyle>`
+as much as possible. Since not all the kernel follows the same style,
+it is possible that you may want to tweak the defaults for a particular
+subsystem or folder. To do so, you can override the defaults by writing
+another ``.clang-format`` file in a subfolder.
+
+The tool itself has already been included in the repositories of popular
+Linux distributions for a long time. Search for ``clang-format`` in
+your repositories. Otherwise, you can either download pre-built
+LLVM/clang binaries or build the source code from:
+
+ https://releases.llvm.org/download.html
+
+See more information about the tool at:
+
+ https://clang.llvm.org/docs/ClangFormat.html
+
+ https://clang.llvm.org/docs/ClangFormatStyleOptions.html
+
+
+.. _clangformatreview:
+
+Review files and patches for coding style
+-----------------------------------------
+
+By running the tool in its inline mode, you can review full subsystems,
+folders or individual files for code style mistakes, typos or improvements.
+
+To do so, you can run something like::
+
+ # Make sure your working directory is clean!
+ clang-format -i kernel/*.[ch]
+
+And then take a look at the git diff.
+
+Counting the lines of such a diff is also useful for improving/tweaking
+the style options in the configuration file; as well as testing new
+``clang-format`` features/versions.
+
+``clang-format`` also supports reading unified diffs, so you can review
+patches and git diffs easily. See the documentation at:
+
+ https://clang.llvm.org/docs/ClangFormat.html#script-for-patch-reformatting
+
+To avoid ``clang-format`` formatting some portion of a file, you can do::
+
+ int formatted_code;
+ // clang-format off
+ void unformatted_code ;
+ // clang-format on
+ void formatted_code_again;
+
+While it might be tempting to use this to keep a file always in sync with
+``clang-format``, specially if you are writing new files or if you are
+a maintainer, please note that people might be running different
+``clang-format`` versions or not have it available at all. Therefore,
+you should probably refrain yourself from using this in kernel sources;
+at least until we see if ``clang-format`` becomes commonplace.
+
+
+.. _clangformatreformat:
+
+Reformatting blocks of code
+---------------------------
+
+By using an integration with your text editor, you can reformat arbitrary
+blocks (selections) of code with a single keystroke. This is specially
+useful when moving code around, for complex code that is deeply intended,
+for multi-line macros (and aligning their backslashes), etc.
+
+Remember that you can always tweak the changes afterwards in those cases
+where the tool did not do an optimal job. But as a first approximation,
+it can be very useful.
+
+There are integrations for many popular text editors. For some of them,
+like vim, emacs, BBEdit and Visual Studio you can find support built-in.
+For instructions, read the appropriate section at:
+
+ https://clang.llvm.org/docs/ClangFormat.html
+
+For Atom, Eclipse, Sublime Text, Visual Studio Code, XCode and other
+editors and IDEs you should be able to find ready-to-use plugins.
+
+For this use case, consider using a secondary ``.clang-format``
+so that you can tweak a few options. See clangformatextra_.
+
+
+.. _clangformatmissing:
+
+Missing support
+---------------
+
+``clang-format`` is missing support for some things that are common
+in kernel code. They are easy to remember, so if you use the tool
+regularly, you will quickly learn to avoid/ignore those.
+
+In particular, some very common ones you will notice are:
+
+ - Aligned blocks of one-line ``#defines``, e.g.::
+
+ #define TRACING_MAP_BITS_DEFAULT 11
+ #define TRACING_MAP_BITS_MAX 17
+ #define TRACING_MAP_BITS_MIN 7
+
+ vs.::
+
+ #define TRACING_MAP_BITS_DEFAULT 11
+ #define TRACING_MAP_BITS_MAX 17
+ #define TRACING_MAP_BITS_MIN 7
+
+ - Aligned designated initializers, e.g.::
+
+ static const struct file_operations uprobe_events_ops = {
+ .owner = THIS_MODULE,
+ .open = probes_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+ .write = probes_write,
+ };
+
+ vs.::
+
+ static const struct file_operations uprobe_events_ops = {
+ .owner = THIS_MODULE,
+ .open = probes_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+ .write = probes_write,
+ };
+
+
+.. _clangformatextra:
+
+Extra features/options
+----------------------
+
+Some features/style options are not enabled by default in the configuration
+file in order to minimize the differences between the output and the current
+code. In other words, to make the difference as small as possible,
+which makes reviewing full-file style, as well diffs and patches as easy
+as possible.
+
+In other cases (e.g. particular subsystems/folders/files), the kernel style
+might be different and enabling some of these options may approximate
+better the style there.
+
+For instance:
+
+ - Aligning assignments (``AlignConsecutiveAssignments``).
+
+ - Aligning declarations (``AlignConsecutiveDeclarations``).
+
+ - Reflowing text in comments (``ReflowComments``).
+
+ - Sorting ``#includes`` (``SortIncludes``).
+
+They are typically useful for block re-formatting, rather than full-file.
+You might want to create another ``.clang-format`` file and use that one
+from your editor/IDE instead.