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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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+Deterministic Automata Instrumentation
+======================================
+
+The RV monitor file created by dot2k, with the name "$MODEL_NAME.c"
+includes a section dedicated to instrumentation.
+
+In the example of the wip.dot monitor created on [1], it will look like::
+
+ /*
+ * This is the instrumentation part of the monitor.
+ *
+ * This is the section where manual work is required. Here the kernel events
+ * are translated into model's event.
+ *
+ */
+ static void handle_preempt_disable(void *data, /* XXX: fill header */)
+ {
+ da_handle_event_wip(preempt_disable_wip);
+ }
+
+ static void handle_preempt_enable(void *data, /* XXX: fill header */)
+ {
+ da_handle_event_wip(preempt_enable_wip);
+ }
+
+ static void handle_sched_waking(void *data, /* XXX: fill header */)
+ {
+ da_handle_event_wip(sched_waking_wip);
+ }
+
+ static int enable_wip(void)
+ {
+ int retval;
+
+ retval = da_monitor_init_wip();
+ if (retval)
+ return retval;
+
+ rv_attach_trace_probe("wip", /* XXX: tracepoint */, handle_preempt_disable);
+ rv_attach_trace_probe("wip", /* XXX: tracepoint */, handle_preempt_enable);
+ rv_attach_trace_probe("wip", /* XXX: tracepoint */, handle_sched_waking);
+
+ return 0;
+ }
+
+The comment at the top of the section explains the general idea: the
+instrumentation section translates *kernel events* into the *model's
+event*.
+
+Tracing callback functions
+--------------------------
+
+The first three functions are the starting point of the callback *handler
+functions* for each of the three events from the wip model. The developer
+does not necessarily need to use them: they are just starting points.
+
+Using the example of::
+
+ void handle_preempt_disable(void *data, /* XXX: fill header */)
+ {
+ da_handle_event_wip(preempt_disable_wip);
+ }
+
+The preempt_disable event from the model connects directly to the
+preemptirq:preempt_disable. The preemptirq:preempt_disable event
+has the following signature, from include/trace/events/preemptirq.h::
+
+ TP_PROTO(unsigned long ip, unsigned long parent_ip)
+
+Hence, the handle_preempt_disable() function will look like::
+
+ void handle_preempt_disable(void *data, unsigned long ip, unsigned long parent_ip)
+
+In this case, the kernel event translates one to one with the automata
+event, and indeed, no other change is required for this function.
+
+The next handler function, handle_preempt_enable() has the same argument
+list from the handle_preempt_disable(). The difference is that the
+preempt_enable event will be used to synchronize the system to the model.
+
+Initially, the *model* is placed in the initial state. However, the *system*
+might or might not be in the initial state. The monitor cannot start
+processing events until it knows that the system has reached the initial state.
+Otherwise, the monitor and the system could be out-of-sync.
+
+Looking at the automata definition, it is possible to see that the system
+and the model are expected to return to the initial state after the
+preempt_enable execution. Hence, it can be used to synchronize the
+system and the model at the initialization of the monitoring section.
+
+The start is informed via a special handle function, the
+"da_handle_start_event_$(MONITOR_NAME)(event)", in this case::
+
+ da_handle_start_event_wip(preempt_enable_wip);
+
+So, the callback function will look like::
+
+ void handle_preempt_enable(void *data, unsigned long ip, unsigned long parent_ip)
+ {
+ da_handle_start_event_wip(preempt_enable_wip);
+ }
+
+Finally, the "handle_sched_waking()" will look like::
+
+ void handle_sched_waking(void *data, struct task_struct *task)
+ {
+ da_handle_event_wip(sched_waking_wip);
+ }
+
+And the explanation is left for the reader as an exercise.
+
+enable and disable functions
+----------------------------
+
+dot2k automatically creates two special functions::
+
+ enable_$(MONITOR_NAME)()
+ disable_$(MONITOR_NAME)()
+
+These functions are called when the monitor is enabled and disabled,
+respectively.
+
+They should be used to *attach* and *detach* the instrumentation to the running
+system. The developer must add to the relative function all that is needed to
+*attach* and *detach* its monitor to the system.
+
+For the wip case, these functions were named::
+
+ enable_wip()
+ disable_wip()
+
+But no change was required because: by default, these functions *attach* and
+*detach* the tracepoints_to_attach, which was enough for this case.
+
+Instrumentation helpers
+-----------------------
+
+To complete the instrumentation, the *handler functions* need to be attached to a
+kernel event, at the monitoring enable phase.
+
+The RV interface also facilitates this step. For example, the macro "rv_attach_trace_probe()"
+is used to connect the wip model events to the relative kernel event. dot2k automatically
+adds "rv_attach_trace_probe()" function call for each model event in the enable phase, as
+a suggestion.
+
+For example, from the wip sample model::
+
+ static int enable_wip(void)
+ {
+ int retval;
+
+ retval = da_monitor_init_wip();
+ if (retval)
+ return retval;
+
+ rv_attach_trace_probe("wip", /* XXX: tracepoint */, handle_preempt_enable);
+ rv_attach_trace_probe("wip", /* XXX: tracepoint */, handle_sched_waking);
+ rv_attach_trace_probe("wip", /* XXX: tracepoint */, handle_preempt_disable);
+
+ return 0;
+ }
+
+The probes then need to be detached at the disable phase.
+
+[1] The wip model is presented in::
+
+ Documentation/trace/rv/deterministic_automata.rst
+
+The wip monitor is presented in::
+
+ Documentation/trace/rv/da_monitor_synthesis.rst