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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 /Documentation/admin-guide/mm/numaperf.rst | |
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 'Documentation/admin-guide/mm/numaperf.rst')
-rw-r--r-- | Documentation/admin-guide/mm/numaperf.rst | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/Documentation/admin-guide/mm/numaperf.rst b/Documentation/admin-guide/mm/numaperf.rst new file mode 100644 index 000000000..166697325 --- /dev/null +++ b/Documentation/admin-guide/mm/numaperf.rst @@ -0,0 +1,178 @@ +.. _numaperf: + +============= +NUMA Locality +============= + +Some platforms may have multiple types of memory attached to a compute +node. These disparate memory ranges may share some characteristics, such +as CPU cache coherence, but may have different performance. For example, +different media types and buses affect bandwidth and latency. + +A system supports such heterogeneous memory by grouping each memory type +under different domains, or "nodes", based on locality and performance +characteristics. Some memory may share the same node as a CPU, and others +are provided as memory only nodes. While memory only nodes do not provide +CPUs, they may still be local to one or more compute nodes relative to +other nodes. The following diagram shows one such example of two compute +nodes with local memory and a memory only node for each of compute node:: + + +------------------+ +------------------+ + | Compute Node 0 +-----+ Compute Node 1 | + | Local Node0 Mem | | Local Node1 Mem | + +--------+---------+ +--------+---------+ + | | + +--------+---------+ +--------+---------+ + | Slower Node2 Mem | | Slower Node3 Mem | + +------------------+ +--------+---------+ + +A "memory initiator" is a node containing one or more devices such as +CPUs or separate memory I/O devices that can initiate memory requests. +A "memory target" is a node containing one or more physical address +ranges accessible from one or more memory initiators. + +When multiple memory initiators exist, they may not all have the same +performance when accessing a given memory target. Each initiator-target +pair may be organized into different ranked access classes to represent +this relationship. The highest performing initiator to a given target +is considered to be one of that target's local initiators, and given +the highest access class, 0. Any given target may have one or more +local initiators, and any given initiator may have multiple local +memory targets. + +To aid applications matching memory targets with their initiators, the +kernel provides symlinks to each other. The following example lists the +relationship for the access class "0" memory initiators and targets:: + + # symlinks -v /sys/devices/system/node/nodeX/access0/targets/ + relative: /sys/devices/system/node/nodeX/access0/targets/nodeY -> ../../nodeY + + # symlinks -v /sys/devices/system/node/nodeY/access0/initiators/ + relative: /sys/devices/system/node/nodeY/access0/initiators/nodeX -> ../../nodeX + +A memory initiator may have multiple memory targets in the same access +class. The target memory's initiators in a given class indicate the +nodes' access characteristics share the same performance relative to other +linked initiator nodes. Each target within an initiator's access class, +though, do not necessarily perform the same as each other. + +The access class "1" is used to allow differentiation between initiators +that are CPUs and hence suitable for generic task scheduling, and +IO initiators such as GPUs and NICs. Unlike access class 0, only +nodes containing CPUs are considered. + +================ +NUMA Performance +================ + +Applications may wish to consider which node they want their memory to +be allocated from based on the node's performance characteristics. If +the system provides these attributes, the kernel exports them under the +node sysfs hierarchy by appending the attributes directory under the +memory node's access class 0 initiators as follows:: + + /sys/devices/system/node/nodeY/access0/initiators/ + +These attributes apply only when accessed from nodes that have the +are linked under the this access's initiators. + +The performance characteristics the kernel provides for the local initiators +are exported are as follows:: + + # tree -P "read*|write*" /sys/devices/system/node/nodeY/access0/initiators/ + /sys/devices/system/node/nodeY/access0/initiators/ + |-- read_bandwidth + |-- read_latency + |-- write_bandwidth + `-- write_latency + +The bandwidth attributes are provided in MiB/second. + +The latency attributes are provided in nanoseconds. + +The values reported here correspond to the rated latency and bandwidth +for the platform. + +Access class 1 takes the same form but only includes values for CPU to +memory activity. + +========== +NUMA Cache +========== + +System memory may be constructed in a hierarchy of elements with various +performance characteristics in order to provide large address space of +slower performing memory cached by a smaller higher performing memory. The +system physical addresses memory initiators are aware of are provided +by the last memory level in the hierarchy. The system meanwhile uses +higher performing memory to transparently cache access to progressively +slower levels. + +The term "far memory" is used to denote the last level memory in the +hierarchy. Each increasing cache level provides higher performing +initiator access, and the term "near memory" represents the fastest +cache provided by the system. + +This numbering is different than CPU caches where the cache level (ex: +L1, L2, L3) uses the CPU-side view where each increased level is lower +performing. In contrast, the memory cache level is centric to the last +level memory, so the higher numbered cache level corresponds to memory +nearer to the CPU, and further from far memory. + +The memory-side caches are not directly addressable by software. When +software accesses a system address, the system will return it from the +near memory cache if it is present. If it is not present, the system +accesses the next level of memory until there is either a hit in that +cache level, or it reaches far memory. + +An application does not need to know about caching attributes in order +to use the system. Software may optionally query the memory cache +attributes in order to maximize the performance out of such a setup. +If the system provides a way for the kernel to discover this information, +for example with ACPI HMAT (Heterogeneous Memory Attribute Table), +the kernel will append these attributes to the NUMA node memory target. + +When the kernel first registers a memory cache with a node, the kernel +will create the following directory:: + + /sys/devices/system/node/nodeX/memory_side_cache/ + +If that directory is not present, the system either does not provide +a memory-side cache, or that information is not accessible to the kernel. + +The attributes for each level of cache is provided under its cache +level index:: + + /sys/devices/system/node/nodeX/memory_side_cache/indexA/ + /sys/devices/system/node/nodeX/memory_side_cache/indexB/ + /sys/devices/system/node/nodeX/memory_side_cache/indexC/ + +Each cache level's directory provides its attributes. For example, the +following shows a single cache level and the attributes available for +software to query:: + + # tree /sys/devices/system/node/node0/memory_side_cache/ + /sys/devices/system/node/node0/memory_side_cache/ + |-- index1 + | |-- indexing + | |-- line_size + | |-- size + | `-- write_policy + +The "indexing" will be 0 if it is a direct-mapped cache, and non-zero +for any other indexed based, multi-way associativity. + +The "line_size" is the number of bytes accessed from the next cache +level on a miss. + +The "size" is the number of bytes provided by this cache level. + +The "write_policy" will be 0 for write-back, and non-zero for +write-through caching. + +======== +See Also +======== + +[1] https://www.uefi.org/sites/default/files/resources/ACPI_6_2.pdf +- Section 5.2.27 |