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author | 2023-02-21 18:24:12 -0800 | |
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committer | 2023-02-21 18:24:12 -0800 | |
commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /tools/virtio/ringtest/ring.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 'tools/virtio/ringtest/ring.c')
-rw-r--r-- | tools/virtio/ringtest/ring.c | 270 |
1 files changed, 270 insertions, 0 deletions
diff --git a/tools/virtio/ringtest/ring.c b/tools/virtio/ringtest/ring.c new file mode 100644 index 000000000..58e7d33bd --- /dev/null +++ b/tools/virtio/ringtest/ring.c @@ -0,0 +1,270 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2016 Red Hat, Inc. + * Author: Michael S. Tsirkin <mst@redhat.com> + * + * Simple descriptor-based ring. virtio 0.9 compatible event index is used for + * signalling, unconditionally. + */ +#define _GNU_SOURCE +#include "main.h" +#include <stdlib.h> +#include <stdio.h> +#include <string.h> + +/* Next - Where next entry will be written. + * Prev - "Next" value when event triggered previously. + * Event - Peer requested event after writing this entry. + */ +static inline bool need_event(unsigned short event, + unsigned short next, + unsigned short prev) +{ + return (unsigned short)(next - event - 1) < (unsigned short)(next - prev); +} + +/* Design: + * Guest adds descriptors with unique index values and DESC_HW in flags. + * Host overwrites used descriptors with correct len, index, and DESC_HW clear. + * Flags are always set last. + */ +#define DESC_HW 0x1 + +struct desc { + unsigned short flags; + unsigned short index; + unsigned len; + unsigned long long addr; +}; + +/* how much padding is needed to avoid false cache sharing */ +#define HOST_GUEST_PADDING 0x80 + +/* Mostly read */ +struct event { + unsigned short kick_index; + unsigned char reserved0[HOST_GUEST_PADDING - 2]; + unsigned short call_index; + unsigned char reserved1[HOST_GUEST_PADDING - 2]; +}; + +struct data { + void *buf; /* descriptor is writeable, we can't get buf from there */ + void *data; +} *data; + +struct desc *ring; +struct event *event; + +struct guest { + unsigned avail_idx; + unsigned last_used_idx; + unsigned num_free; + unsigned kicked_avail_idx; + unsigned char reserved[HOST_GUEST_PADDING - 12]; +} guest; + +struct host { + /* we do not need to track last avail index + * unless we have more than one in flight. + */ + unsigned used_idx; + unsigned called_used_idx; + unsigned char reserved[HOST_GUEST_PADDING - 4]; +} host; + +/* implemented by ring */ +void alloc_ring(void) +{ + int ret; + int i; + + ret = posix_memalign((void **)&ring, 0x1000, ring_size * sizeof *ring); + if (ret) { + perror("Unable to allocate ring buffer.\n"); + exit(3); + } + event = calloc(1, sizeof(*event)); + if (!event) { + perror("Unable to allocate event buffer.\n"); + exit(3); + } + guest.avail_idx = 0; + guest.kicked_avail_idx = -1; + guest.last_used_idx = 0; + host.used_idx = 0; + host.called_used_idx = -1; + for (i = 0; i < ring_size; ++i) { + struct desc desc = { + .index = i, + }; + ring[i] = desc; + } + guest.num_free = ring_size; + data = calloc(ring_size, sizeof(*data)); + if (!data) { + perror("Unable to allocate data buffer.\n"); + exit(3); + } +} + +/* guest side */ +int add_inbuf(unsigned len, void *buf, void *datap) +{ + unsigned head, index; + + if (!guest.num_free) + return -1; + + guest.num_free--; + head = (ring_size - 1) & (guest.avail_idx++); + + /* Start with a write. On MESI architectures this helps + * avoid a shared state with consumer that is polling this descriptor. + */ + ring[head].addr = (unsigned long)(void*)buf; + ring[head].len = len; + /* read below might bypass write above. That is OK because it's just an + * optimization. If this happens, we will get the cache line in a + * shared state which is unfortunate, but probably not worth it to + * add an explicit full barrier to avoid this. + */ + barrier(); + index = ring[head].index; + data[index].buf = buf; + data[index].data = datap; + /* Barrier A (for pairing) */ + smp_release(); + ring[head].flags = DESC_HW; + + return 0; +} + +void *get_buf(unsigned *lenp, void **bufp) +{ + unsigned head = (ring_size - 1) & guest.last_used_idx; + unsigned index; + void *datap; + + if (ring[head].flags & DESC_HW) + return NULL; + /* Barrier B (for pairing) */ + smp_acquire(); + *lenp = ring[head].len; + index = ring[head].index & (ring_size - 1); + datap = data[index].data; + *bufp = data[index].buf; + data[index].buf = NULL; + data[index].data = NULL; + guest.num_free++; + guest.last_used_idx++; + return datap; +} + +bool used_empty() +{ + unsigned head = (ring_size - 1) & guest.last_used_idx; + + return (ring[head].flags & DESC_HW); +} + +void disable_call() +{ + /* Doing nothing to disable calls might cause + * extra interrupts, but reduces the number of cache misses. + */ +} + +bool enable_call() +{ + event->call_index = guest.last_used_idx; + /* Flush call index write */ + /* Barrier D (for pairing) */ + smp_mb(); + return used_empty(); +} + +void kick_available(void) +{ + bool need; + + /* Flush in previous flags write */ + /* Barrier C (for pairing) */ + smp_mb(); + need = need_event(event->kick_index, + guest.avail_idx, + guest.kicked_avail_idx); + + guest.kicked_avail_idx = guest.avail_idx; + if (need) + kick(); +} + +/* host side */ +void disable_kick() +{ + /* Doing nothing to disable kicks might cause + * extra interrupts, but reduces the number of cache misses. + */ +} + +bool enable_kick() +{ + event->kick_index = host.used_idx; + /* Barrier C (for pairing) */ + smp_mb(); + return avail_empty(); +} + +bool avail_empty() +{ + unsigned head = (ring_size - 1) & host.used_idx; + + return !(ring[head].flags & DESC_HW); +} + +bool use_buf(unsigned *lenp, void **bufp) +{ + unsigned head = (ring_size - 1) & host.used_idx; + + if (!(ring[head].flags & DESC_HW)) + return false; + + /* make sure length read below is not speculated */ + /* Barrier A (for pairing) */ + smp_acquire(); + + /* simple in-order completion: we don't need + * to touch index at all. This also means we + * can just modify the descriptor in-place. + */ + ring[head].len--; + /* Make sure len is valid before flags. + * Note: alternative is to write len and flags in one access - + * possible on 64 bit architectures but wmb is free on Intel anyway + * so I have no way to test whether it's a gain. + */ + /* Barrier B (for pairing) */ + smp_release(); + ring[head].flags = 0; + host.used_idx++; + return true; +} + +void call_used(void) +{ + bool need; + + /* Flush in previous flags write */ + /* Barrier D (for pairing) */ + smp_mb(); + + need = need_event(event->call_index, + host.used_idx, + host.called_used_idx); + + host.called_used_idx = host.used_idx; + + if (need) + call(); +} |