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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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+.. SPDX-License-Identifier: GPL-2.0
+
+=============
+Page Pool API
+=============
+
+The page_pool allocator is optimized for the XDP mode that uses one frame
+per-page, but it can fallback on the regular page allocator APIs.
+
+Basic use involves replacing alloc_pages() calls with the
+page_pool_alloc_pages() call. Drivers should use page_pool_dev_alloc_pages()
+replacing dev_alloc_pages().
+
+API keeps track of in-flight pages, in order to let API user know
+when it is safe to free a page_pool object. Thus, API users
+must run page_pool_release_page() when a page is leaving the page_pool or
+call page_pool_put_page() where appropriate in order to maintain correct
+accounting.
+
+API user must call page_pool_put_page() once on a page, as it
+will either recycle the page, or in case of refcnt > 1, it will
+release the DMA mapping and in-flight state accounting.
+
+Architecture overview
+=====================
+
+.. code-block:: none
+
+ +------------------+
+ | Driver |
+ +------------------+
+ ^
+ |
+ |
+ |
+ v
+ +--------------------------------------------+
+ | request memory |
+ +--------------------------------------------+
+ ^ ^
+ | |
+ | Pool empty | Pool has entries
+ | |
+ v v
+ +-----------------------+ +------------------------+
+ | alloc (and map) pages | | get page from cache |
+ +-----------------------+ +------------------------+
+ ^ ^
+ | |
+ | cache available | No entries, refill
+ | | from ptr-ring
+ | |
+ v v
+ +-----------------+ +------------------+
+ | Fast cache | | ptr-ring cache |
+ +-----------------+ +------------------+
+
+API interface
+=============
+The number of pools created **must** match the number of hardware queues
+unless hardware restrictions make that impossible. This would otherwise beat the
+purpose of page pool, which is allocate pages fast from cache without locking.
+This lockless guarantee naturally comes from running under a NAPI softirq.
+The protection doesn't strictly have to be NAPI, any guarantee that allocating
+a page will cause no race conditions is enough.
+
+* page_pool_create(): Create a pool.
+ * flags: PP_FLAG_DMA_MAP, PP_FLAG_DMA_SYNC_DEV
+ * order: 2^order pages on allocation
+ * pool_size: size of the ptr_ring
+ * nid: preferred NUMA node for allocation
+ * dev: struct device. Used on DMA operations
+ * dma_dir: DMA direction
+ * max_len: max DMA sync memory size
+ * offset: DMA address offset
+
+* page_pool_put_page(): The outcome of this depends on the page refcnt. If the
+ driver bumps the refcnt > 1 this will unmap the page. If the page refcnt is 1
+ the allocator owns the page and will try to recycle it in one of the pool
+ caches. If PP_FLAG_DMA_SYNC_DEV is set, the page will be synced for_device
+ using dma_sync_single_range_for_device().
+
+* page_pool_put_full_page(): Similar to page_pool_put_page(), but will DMA sync
+ for the entire memory area configured in area pool->max_len.
+
+* page_pool_recycle_direct(): Similar to page_pool_put_full_page() but caller
+ must guarantee safe context (e.g NAPI), since it will recycle the page
+ directly into the pool fast cache.
+
+* page_pool_release_page(): Unmap the page (if mapped) and account for it on
+ in-flight counters.
+
+* page_pool_dev_alloc_pages(): Get a page from the page allocator or page_pool
+ caches.
+
+* page_pool_get_dma_addr(): Retrieve the stored DMA address.
+
+* page_pool_get_dma_dir(): Retrieve the stored DMA direction.
+
+* page_pool_put_page_bulk(): Tries to refill a number of pages into the
+ ptr_ring cache holding ptr_ring producer lock. If the ptr_ring is full,
+ page_pool_put_page_bulk() will release leftover pages to the page allocator.
+ page_pool_put_page_bulk() is suitable to be run inside the driver NAPI tx
+ completion loop for the XDP_REDIRECT use case.
+ Please note the caller must not use data area after running
+ page_pool_put_page_bulk(), as this function overwrites it.
+
+* page_pool_get_stats(): Retrieve statistics about the page_pool. This API
+ is only available if the kernel has been configured with
+ ``CONFIG_PAGE_POOL_STATS=y``. A pointer to a caller allocated ``struct
+ page_pool_stats`` structure is passed to this API which is filled in. The
+ caller can then report those stats to the user (perhaps via ethtool,
+ debugfs, etc.). See below for an example usage of this API.
+
+Stats API and structures
+------------------------
+If the kernel is configured with ``CONFIG_PAGE_POOL_STATS=y``, the API
+``page_pool_get_stats()`` and structures described below are available. It
+takes a pointer to a ``struct page_pool`` and a pointer to a ``struct
+page_pool_stats`` allocated by the caller.
+
+The API will fill in the provided ``struct page_pool_stats`` with
+statistics about the page_pool.
+
+The stats structure has the following fields::
+
+ struct page_pool_stats {
+ struct page_pool_alloc_stats alloc_stats;
+ struct page_pool_recycle_stats recycle_stats;
+ };
+
+
+The ``struct page_pool_alloc_stats`` has the following fields:
+ * ``fast``: successful fast path allocations
+ * ``slow``: slow path order-0 allocations
+ * ``slow_high_order``: slow path high order allocations
+ * ``empty``: ptr ring is empty, so a slow path allocation was forced.
+ * ``refill``: an allocation which triggered a refill of the cache
+ * ``waive``: pages obtained from the ptr ring that cannot be added to
+ the cache due to a NUMA mismatch.
+
+The ``struct page_pool_recycle_stats`` has the following fields:
+ * ``cached``: recycling placed page in the page pool cache
+ * ``cache_full``: page pool cache was full
+ * ``ring``: page placed into the ptr ring
+ * ``ring_full``: page released from page pool because the ptr ring was full
+ * ``released_refcnt``: page released (and not recycled) because refcnt > 1
+
+Coding examples
+===============
+
+Registration
+------------
+
+.. code-block:: c
+
+ /* Page pool registration */
+ struct page_pool_params pp_params = { 0 };
+ struct xdp_rxq_info xdp_rxq;
+ int err;
+
+ pp_params.order = 0;
+ /* internal DMA mapping in page_pool */
+ pp_params.flags = PP_FLAG_DMA_MAP;
+ pp_params.pool_size = DESC_NUM;
+ pp_params.nid = NUMA_NO_NODE;
+ pp_params.dev = priv->dev;
+ pp_params.dma_dir = xdp_prog ? DMA_BIDIRECTIONAL : DMA_FROM_DEVICE;
+ page_pool = page_pool_create(&pp_params);
+
+ err = xdp_rxq_info_reg(&xdp_rxq, ndev, 0);
+ if (err)
+ goto err_out;
+
+ err = xdp_rxq_info_reg_mem_model(&xdp_rxq, MEM_TYPE_PAGE_POOL, page_pool);
+ if (err)
+ goto err_out;
+
+NAPI poller
+-----------
+
+
+.. code-block:: c
+
+ /* NAPI Rx poller */
+ enum dma_data_direction dma_dir;
+
+ dma_dir = page_pool_get_dma_dir(dring->page_pool);
+ while (done < budget) {
+ if (some error)
+ page_pool_recycle_direct(page_pool, page);
+ if (packet_is_xdp) {
+ if XDP_DROP:
+ page_pool_recycle_direct(page_pool, page);
+ } else (packet_is_skb) {
+ page_pool_release_page(page_pool, page);
+ new_page = page_pool_dev_alloc_pages(page_pool);
+ }
+ }
+
+Stats
+-----
+
+.. code-block:: c
+
+ #ifdef CONFIG_PAGE_POOL_STATS
+ /* retrieve stats */
+ struct page_pool_stats stats = { 0 };
+ if (page_pool_get_stats(page_pool, &stats)) {
+ /* perhaps the driver reports statistics with ethool */
+ ethtool_print_allocation_stats(&stats.alloc_stats);
+ ethtool_print_recycle_stats(&stats.recycle_stats);
+ }
+ #endif
+
+Driver unload
+-------------
+
+.. code-block:: c
+
+ /* Driver unload */
+ page_pool_put_full_page(page_pool, page, false);
+ xdp_rxq_info_unreg(&xdp_rxq);