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().
  ...

1 files changed, 145 insertions, 0 deletions

diff --git a/Documentation/translations/zh_CN/locking/mutex-design.rst b/Documentation/translations/zh_CN/locking/mutex-design.rst
new file mode 100644
index 000000000..6aad54372
--- /dev/null
+++ b/Documentation/translations/zh_CN/locking/mutex-design.rst
@@ -0,0 +1,145 @@
+.. SPDX-License-Identifier: GPL-2.0
+.. include:: ../disclaimer-zh_CN.rst
+
+:Original: Documentation/locking/mutex-design.rst
+
+:翻译:
+
+  唐艺舟 Tang Yizhou <tangyeechou@gmail.com>
+
+================
+通用互斥锁子系统
+================
+
+:初稿:
+
+  Ingo Molnar <mingo@redhat.com>
+
+:更新:
+
+  Davidlohr Bueso <davidlohr@hp.com>
+
+什么是互斥锁？
+--------------
+
+在Linux内核中，互斥锁（mutex）指的是一个特殊的加锁原语，它在共享内存系统上
+强制保证序列化，而不仅仅是指在学术界或类似的理论教科书中出现的通用术语“相互
+排斥”。互斥锁是一种睡眠锁，它的行为类似于二进制信号量（semaphores），在
+2006年被引入时[1]，作为后者的替代品。这种新的数据结构提供了许多优点，包括更
+简单的接口，以及在当时更少的代码量（见缺陷）。
+
+[1] https://lwn.net/Articles/164802/
+
+实现
+----
+
+互斥锁由“struct mutex”表示，在include/linux/mutex.h中定义，并在
+kernel/locking/mutex.c中实现。这些锁使用一个原子变量（->owner）来跟踪
+它们生命周期内的锁状态。字段owner实际上包含的是指向当前锁所有者的
+`struct task_struct *` 指针，因此如果无人持有锁，则它的值为空（NULL）。
+由于task_struct的指针至少按L1_CACHE_BYTES对齐，低位（3）被用来存储额外
+的状态（例如，等待者列表非空）。在其最基本的形式中，它还包括一个等待队列和
+一个确保对其序列化访问的自旋锁。此外，CONFIG_MUTEX_SPIN_ON_OWNER=y的
+系统使用一个自旋MCS锁（->osq，译注：MCS是两个人名的合并缩写），在下文的
+（ii）中描述。
+
+准备获得一把自旋锁时，有三种可能经过的路径，取决于锁的状态：
+
+(i) 快速路径：试图通过调用cmpxchg()修改锁的所有者为当前任务，以此原子化地
+    获取锁。这只在无竞争的情况下有效（cmpxchg()检查值是否为0，所以3个状态
+    比特必须为0）。如果锁处在竞争状态，代码进入下一个可能的路径。
+
+(ii) 中速路径：也就是乐观自旋，当锁的所有者正在运行并且没有其它优先级更高的
+     任务（need_resched，需要重新调度）准备运行时，当前任务试图自旋来获得
+     锁。原理是，如果锁的所有者正在运行，它很可能不久就会释放锁。互斥锁自旋体
+     使用MCS锁排队，这样只有一个自旋体可以竞争互斥锁。
+
+     MCS锁（由Mellor-Crummey和Scott提出）是一个简单的自旋锁，它具有一些
+     理想的特性，比如公平，以及每个CPU在试图获得锁时在一个本地变量上自旋。
+     它避免了常见的“检测-设置”自旋锁实现导致的（CPU核间）缓存行回弹
+     （cacheline bouncing）这种昂贵的开销。一个类MCS锁是为实现睡眠锁的
+     乐观自旋而专门定制的。这种定制MCS锁的一个重要特性是，它有一个额外的属性，
+     当自旋体需要重新调度时，它们能够退出MCS自旋锁队列。这进一步有助于避免
+     以下场景：需要重新调度的MCS自旋体将继续自旋等待自旋体所有者，即将获得
+     MCS锁时却直接进入慢速路径。
+
+(iii) 慢速路径：最后的手段，如果仍然无法获得锁，该任务会被添加到等待队列中，
+      休眠直到被解锁路径唤醒。在通常情况下，它以TASK_UNINTERRUPTIBLE状态
+      阻塞。
+
+虽然从形式上看，内核互斥锁是可睡眠的锁，路径(ii)使它实际上成为混合类型。通过
+简单地不中断一个任务并忙着等待几个周期，而不是立即睡眠，这种锁已经被认为显著
+改善一些工作负载的性能。注意，这种技术也被用于读写信号量（rw-semaphores）。
+
+语义
+----
+
+互斥锁子系统检查并强制执行以下规则:
+
+    - 每次只有一个任务可以持有该互斥锁。
+    - 只有锁的所有者可以解锁该互斥锁。
+    - 不允许多次解锁。
+    - 不允许递归加锁/解锁。
+    - 互斥锁只能通过API进行初始化（见下文）。
+    - 一个任务不能在持有互斥锁的情况下退出。
+    - 持有锁的内存区域不得被释放。
+    - 被持有的锁不能被重新初始化。
+    - 互斥锁不能用于硬件或软件中断上下文，如小任务（tasklet）和定时器。
+
+当CONFIG DEBUG_MUTEXES被启用时，这些语义将被完全强制执行。此外，互斥锁
+调试代码还实现了一些其它特性，使锁的调试更容易、更快速：
+
+    - 当打印到调试输出时，总是使用互斥锁的符号名称。
+    - 加锁点跟踪，函数名符号化查找，系统持有的全部锁的列表，打印出它们。
+    - 所有者跟踪。
+    - 检测自我递归的锁并打印所有相关信息。
+    - 检测多任务环形依赖死锁，并打印所有受影响的锁和任务（并且只限于这些任务）。
+
+
+接口
+----
+静态定义互斥锁::
+
+   DEFINE_MUTEX(name);
+
+动态初始化互斥锁::
+
+   mutex_init(mutex);
+
+以不可中断方式（uninterruptible）获取互斥锁::
+
+   void mutex_lock(struct mutex *lock);
+   void mutex_lock_nested(struct mutex *lock, unsigned int subclass);
+   int  mutex_trylock(struct mutex *lock);
+
+以可中断方式（interruptible）获取互斥锁::
+
+   int mutex_lock_interruptible_nested(struct mutex *lock,
+				       unsigned int subclass);
+   int mutex_lock_interruptible(struct mutex *lock);
+
+当原子变量减为0时，以可中断方式（interruptible）获取互斥锁::
+
+   int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock);
+
+释放互斥锁::
+
+   void mutex_unlock(struct mutex *lock);
+
+检测是否已经获取互斥锁::
+
+   int mutex_is_locked(struct mutex *lock);
+
+缺陷
+----
+
+与它最初的设计和目的不同，'struct mutex' 是内核中最大的锁之一。例如：在
+x86-64上它是32字节，而 'struct semaphore' 是24字节，rw_semaphore是
+40字节。更大的结构体大小意味着更多的CPU缓存和内存占用。
+
+
+何时使用互斥锁
+--------------
+
+总是优先选择互斥锁而不是任何其它锁原语，除非互斥锁的严格语义不合适，和/或临界区
+阻止锁被共享。