diff options
author | 2023-02-21 18:24:12 -0800 | |
---|---|---|
committer | 2023-02-21 18:24:12 -0800 | |
commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /net/sched/sch_plug.c | |
download | linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip |
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().
...
Diffstat (limited to '')
-rw-r--r-- | net/sched/sch_plug.c | 228 |
1 files changed, 228 insertions, 0 deletions
diff --git a/net/sched/sch_plug.c b/net/sched/sch_plug.c new file mode 100644 index 000000000..ea8c4a717 --- /dev/null +++ b/net/sched/sch_plug.c @@ -0,0 +1,228 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * sch_plug.c Queue traffic until an explicit release command + * + * There are two ways to use this qdisc: + * 1. A simple "instantaneous" plug/unplug operation, by issuing an alternating + * sequence of TCQ_PLUG_BUFFER & TCQ_PLUG_RELEASE_INDEFINITE commands. + * + * 2. For network output buffering (a.k.a output commit) functionality. + * Output commit property is commonly used by applications using checkpoint + * based fault-tolerance to ensure that the checkpoint from which a system + * is being restored is consistent w.r.t outside world. + * + * Consider for e.g. Remus - a Virtual Machine checkpointing system, + * wherein a VM is checkpointed, say every 50ms. The checkpoint is replicated + * asynchronously to the backup host, while the VM continues executing the + * next epoch speculatively. + * + * The following is a typical sequence of output buffer operations: + * 1.At epoch i, start_buffer(i) + * 2. At end of epoch i (i.e. after 50ms): + * 2.1 Stop VM and take checkpoint(i). + * 2.2 start_buffer(i+1) and Resume VM + * 3. While speculatively executing epoch(i+1), asynchronously replicate + * checkpoint(i) to backup host. + * 4. When checkpoint_ack(i) is received from backup, release_buffer(i) + * Thus, this Qdisc would receive the following sequence of commands: + * TCQ_PLUG_BUFFER (epoch i) + * .. TCQ_PLUG_BUFFER (epoch i+1) + * ....TCQ_PLUG_RELEASE_ONE (epoch i) + * ......TCQ_PLUG_BUFFER (epoch i+2) + * ........ + */ + +#include <linux/module.h> +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/netdevice.h> +#include <linux/skbuff.h> +#include <net/pkt_sched.h> + +/* + * State of the queue, when used for network output buffering: + * + * plug(i+1) plug(i) head + * ------------------+--------------------+----------------> + * | | + * | | + * pkts_current_epoch| pkts_last_epoch |pkts_to_release + * ----------------->|<--------+--------->|+---------------> + * v v + * + */ + +struct plug_sched_data { + /* If true, the dequeue function releases all packets + * from head to end of the queue. The queue turns into + * a pass-through queue for newly arriving packets. + */ + bool unplug_indefinite; + + bool throttled; + + /* Queue Limit in bytes */ + u32 limit; + + /* Number of packets (output) from the current speculatively + * executing epoch. + */ + u32 pkts_current_epoch; + + /* Number of packets corresponding to the recently finished + * epoch. These will be released when we receive a + * TCQ_PLUG_RELEASE_ONE command. This command is typically + * issued after committing a checkpoint at the target. + */ + u32 pkts_last_epoch; + + /* + * Number of packets from the head of the queue, that can + * be released (committed checkpoint). + */ + u32 pkts_to_release; +}; + +static int plug_enqueue(struct sk_buff *skb, struct Qdisc *sch, + struct sk_buff **to_free) +{ + struct plug_sched_data *q = qdisc_priv(sch); + + if (likely(sch->qstats.backlog + skb->len <= q->limit)) { + if (!q->unplug_indefinite) + q->pkts_current_epoch++; + return qdisc_enqueue_tail(skb, sch); + } + + return qdisc_drop(skb, sch, to_free); +} + +static struct sk_buff *plug_dequeue(struct Qdisc *sch) +{ + struct plug_sched_data *q = qdisc_priv(sch); + + if (q->throttled) + return NULL; + + if (!q->unplug_indefinite) { + if (!q->pkts_to_release) { + /* No more packets to dequeue. Block the queue + * and wait for the next release command. + */ + q->throttled = true; + return NULL; + } + q->pkts_to_release--; + } + + return qdisc_dequeue_head(sch); +} + +static int plug_init(struct Qdisc *sch, struct nlattr *opt, + struct netlink_ext_ack *extack) +{ + struct plug_sched_data *q = qdisc_priv(sch); + + q->pkts_current_epoch = 0; + q->pkts_last_epoch = 0; + q->pkts_to_release = 0; + q->unplug_indefinite = false; + + if (opt == NULL) { + q->limit = qdisc_dev(sch)->tx_queue_len + * psched_mtu(qdisc_dev(sch)); + } else { + struct tc_plug_qopt *ctl = nla_data(opt); + + if (nla_len(opt) < sizeof(*ctl)) + return -EINVAL; + + q->limit = ctl->limit; + } + + q->throttled = true; + return 0; +} + +/* Receives 4 types of messages: + * TCQ_PLUG_BUFFER: Inset a plug into the queue and + * buffer any incoming packets + * TCQ_PLUG_RELEASE_ONE: Dequeue packets from queue head + * to beginning of the next plug. + * TCQ_PLUG_RELEASE_INDEFINITE: Dequeue all packets from queue. + * Stop buffering packets until the next TCQ_PLUG_BUFFER + * command is received (just act as a pass-thru queue). + * TCQ_PLUG_LIMIT: Increase/decrease queue size + */ +static int plug_change(struct Qdisc *sch, struct nlattr *opt, + struct netlink_ext_ack *extack) +{ + struct plug_sched_data *q = qdisc_priv(sch); + struct tc_plug_qopt *msg; + + msg = nla_data(opt); + if (nla_len(opt) < sizeof(*msg)) + return -EINVAL; + + switch (msg->action) { + case TCQ_PLUG_BUFFER: + /* Save size of the current buffer */ + q->pkts_last_epoch = q->pkts_current_epoch; + q->pkts_current_epoch = 0; + if (q->unplug_indefinite) + q->throttled = true; + q->unplug_indefinite = false; + break; + case TCQ_PLUG_RELEASE_ONE: + /* Add packets from the last complete buffer to the + * packets to be released set. + */ + q->pkts_to_release += q->pkts_last_epoch; + q->pkts_last_epoch = 0; + q->throttled = false; + netif_schedule_queue(sch->dev_queue); + break; + case TCQ_PLUG_RELEASE_INDEFINITE: + q->unplug_indefinite = true; + q->pkts_to_release = 0; + q->pkts_last_epoch = 0; + q->pkts_current_epoch = 0; + q->throttled = false; + netif_schedule_queue(sch->dev_queue); + break; + case TCQ_PLUG_LIMIT: + /* Limit is supplied in bytes */ + q->limit = msg->limit; + break; + default: + return -EINVAL; + } + + return 0; +} + +static struct Qdisc_ops plug_qdisc_ops __read_mostly = { + .id = "plug", + .priv_size = sizeof(struct plug_sched_data), + .enqueue = plug_enqueue, + .dequeue = plug_dequeue, + .peek = qdisc_peek_head, + .init = plug_init, + .change = plug_change, + .reset = qdisc_reset_queue, + .owner = THIS_MODULE, +}; + +static int __init plug_module_init(void) +{ + return register_qdisc(&plug_qdisc_ops); +} + +static void __exit plug_module_exit(void) +{ + unregister_qdisc(&plug_qdisc_ops); +} +module_init(plug_module_init) +module_exit(plug_module_exit) +MODULE_LICENSE("GPL"); |