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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 /mm/page_counter.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 'mm/page_counter.c')
-rw-r--r-- | mm/page_counter.c | 264 |
1 files changed, 264 insertions, 0 deletions
diff --git a/mm/page_counter.c b/mm/page_counter.c new file mode 100644 index 000000000..db20d6452 --- /dev/null +++ b/mm/page_counter.c @@ -0,0 +1,264 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Lockless hierarchical page accounting & limiting + * + * Copyright (C) 2014 Red Hat, Inc., Johannes Weiner + */ + +#include <linux/page_counter.h> +#include <linux/atomic.h> +#include <linux/kernel.h> +#include <linux/string.h> +#include <linux/sched.h> +#include <linux/bug.h> +#include <asm/page.h> + +static void propagate_protected_usage(struct page_counter *c, + unsigned long usage) +{ + unsigned long protected, old_protected; + long delta; + + if (!c->parent) + return; + + protected = min(usage, READ_ONCE(c->min)); + old_protected = atomic_long_read(&c->min_usage); + if (protected != old_protected) { + old_protected = atomic_long_xchg(&c->min_usage, protected); + delta = protected - old_protected; + if (delta) + atomic_long_add(delta, &c->parent->children_min_usage); + } + + protected = min(usage, READ_ONCE(c->low)); + old_protected = atomic_long_read(&c->low_usage); + if (protected != old_protected) { + old_protected = atomic_long_xchg(&c->low_usage, protected); + delta = protected - old_protected; + if (delta) + atomic_long_add(delta, &c->parent->children_low_usage); + } +} + +/** + * page_counter_cancel - take pages out of the local counter + * @counter: counter + * @nr_pages: number of pages to cancel + */ +void page_counter_cancel(struct page_counter *counter, unsigned long nr_pages) +{ + long new; + + new = atomic_long_sub_return(nr_pages, &counter->usage); + /* More uncharges than charges? */ + if (WARN_ONCE(new < 0, "page_counter underflow: %ld nr_pages=%lu\n", + new, nr_pages)) { + new = 0; + atomic_long_set(&counter->usage, new); + } + propagate_protected_usage(counter, new); +} + +/** + * page_counter_charge - hierarchically charge pages + * @counter: counter + * @nr_pages: number of pages to charge + * + * NOTE: This does not consider any configured counter limits. + */ +void page_counter_charge(struct page_counter *counter, unsigned long nr_pages) +{ + struct page_counter *c; + + for (c = counter; c; c = c->parent) { + long new; + + new = atomic_long_add_return(nr_pages, &c->usage); + propagate_protected_usage(c, new); + /* + * This is indeed racy, but we can live with some + * inaccuracy in the watermark. + */ + if (new > READ_ONCE(c->watermark)) + WRITE_ONCE(c->watermark, new); + } +} + +/** + * page_counter_try_charge - try to hierarchically charge pages + * @counter: counter + * @nr_pages: number of pages to charge + * @fail: points first counter to hit its limit, if any + * + * Returns %true on success, or %false and @fail if the counter or one + * of its ancestors has hit its configured limit. + */ +bool page_counter_try_charge(struct page_counter *counter, + unsigned long nr_pages, + struct page_counter **fail) +{ + struct page_counter *c; + + for (c = counter; c; c = c->parent) { + long new; + /* + * Charge speculatively to avoid an expensive CAS. If + * a bigger charge fails, it might falsely lock out a + * racing smaller charge and send it into reclaim + * early, but the error is limited to the difference + * between the two sizes, which is less than 2M/4M in + * case of a THP locking out a regular page charge. + * + * The atomic_long_add_return() implies a full memory + * barrier between incrementing the count and reading + * the limit. When racing with page_counter_set_max(), + * we either see the new limit or the setter sees the + * counter has changed and retries. + */ + new = atomic_long_add_return(nr_pages, &c->usage); + if (new > c->max) { + atomic_long_sub(nr_pages, &c->usage); + /* + * This is racy, but we can live with some + * inaccuracy in the failcnt which is only used + * to report stats. + */ + data_race(c->failcnt++); + *fail = c; + goto failed; + } + propagate_protected_usage(c, new); + /* + * Just like with failcnt, we can live with some + * inaccuracy in the watermark. + */ + if (new > READ_ONCE(c->watermark)) + WRITE_ONCE(c->watermark, new); + } + return true; + +failed: + for (c = counter; c != *fail; c = c->parent) + page_counter_cancel(c, nr_pages); + + return false; +} + +/** + * page_counter_uncharge - hierarchically uncharge pages + * @counter: counter + * @nr_pages: number of pages to uncharge + */ +void page_counter_uncharge(struct page_counter *counter, unsigned long nr_pages) +{ + struct page_counter *c; + + for (c = counter; c; c = c->parent) + page_counter_cancel(c, nr_pages); +} + +/** + * page_counter_set_max - set the maximum number of pages allowed + * @counter: counter + * @nr_pages: limit to set + * + * Returns 0 on success, -EBUSY if the current number of pages on the + * counter already exceeds the specified limit. + * + * The caller must serialize invocations on the same counter. + */ +int page_counter_set_max(struct page_counter *counter, unsigned long nr_pages) +{ + for (;;) { + unsigned long old; + long usage; + + /* + * Update the limit while making sure that it's not + * below the concurrently-changing counter value. + * + * The xchg implies two full memory barriers before + * and after, so the read-swap-read is ordered and + * ensures coherency with page_counter_try_charge(): + * that function modifies the count before checking + * the limit, so if it sees the old limit, we see the + * modified counter and retry. + */ + usage = page_counter_read(counter); + + if (usage > nr_pages) + return -EBUSY; + + old = xchg(&counter->max, nr_pages); + + if (page_counter_read(counter) <= usage || nr_pages >= old) + return 0; + + counter->max = old; + cond_resched(); + } +} + +/** + * page_counter_set_min - set the amount of protected memory + * @counter: counter + * @nr_pages: value to set + * + * The caller must serialize invocations on the same counter. + */ +void page_counter_set_min(struct page_counter *counter, unsigned long nr_pages) +{ + struct page_counter *c; + + WRITE_ONCE(counter->min, nr_pages); + + for (c = counter; c; c = c->parent) + propagate_protected_usage(c, atomic_long_read(&c->usage)); +} + +/** + * page_counter_set_low - set the amount of protected memory + * @counter: counter + * @nr_pages: value to set + * + * The caller must serialize invocations on the same counter. + */ +void page_counter_set_low(struct page_counter *counter, unsigned long nr_pages) +{ + struct page_counter *c; + + WRITE_ONCE(counter->low, nr_pages); + + for (c = counter; c; c = c->parent) + propagate_protected_usage(c, atomic_long_read(&c->usage)); +} + +/** + * page_counter_memparse - memparse() for page counter limits + * @buf: string to parse + * @max: string meaning maximum possible value + * @nr_pages: returns the result in number of pages + * + * Returns -EINVAL, or 0 and @nr_pages on success. @nr_pages will be + * limited to %PAGE_COUNTER_MAX. + */ +int page_counter_memparse(const char *buf, const char *max, + unsigned long *nr_pages) +{ + char *end; + u64 bytes; + + if (!strcmp(buf, max)) { + *nr_pages = PAGE_COUNTER_MAX; + return 0; + } + + bytes = memparse(buf, &end); + if (*end != '\0') + return -EINVAL; + + *nr_pages = min(bytes / PAGE_SIZE, (u64)PAGE_COUNTER_MAX); + + return 0; +} |