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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
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /mm/page_reporting.c
downloadlinux-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_reporting.c')
-rw-r--r--mm/page_reporting.c415
1 files changed, 415 insertions, 0 deletions
diff --git a/mm/page_reporting.c b/mm/page_reporting.c
new file mode 100644
index 000000000..79a8554f0
--- /dev/null
+++ b/mm/page_reporting.c
@@ -0,0 +1,415 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/mm.h>
+#include <linux/mmzone.h>
+#include <linux/page_reporting.h>
+#include <linux/gfp.h>
+#include <linux/export.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/scatterlist.h>
+
+#include "page_reporting.h"
+#include "internal.h"
+
+/* Initialize to an unsupported value */
+unsigned int page_reporting_order = -1;
+
+static int page_order_update_notify(const char *val, const struct kernel_param *kp)
+{
+ /*
+ * If param is set beyond this limit, order is set to default
+ * pageblock_order value
+ */
+ return param_set_uint_minmax(val, kp, 0, MAX_ORDER-1);
+}
+
+static const struct kernel_param_ops page_reporting_param_ops = {
+ .set = &page_order_update_notify,
+ /*
+ * For the get op, use param_get_int instead of param_get_uint.
+ * This is to make sure that when unset the initialized value of
+ * -1 is shown correctly
+ */
+ .get = &param_get_int,
+};
+
+module_param_cb(page_reporting_order, &page_reporting_param_ops,
+ &page_reporting_order, 0644);
+MODULE_PARM_DESC(page_reporting_order, "Set page reporting order");
+
+/*
+ * This symbol is also a kernel parameter. Export the page_reporting_order
+ * symbol so that other drivers can access it to control order values without
+ * having to introduce another configurable parameter. Only one driver can
+ * register with the page_reporting driver for the service, so we have just
+ * one control parameter for the use case(which can be accessed in both
+ * drivers)
+ */
+EXPORT_SYMBOL_GPL(page_reporting_order);
+
+#define PAGE_REPORTING_DELAY (2 * HZ)
+static struct page_reporting_dev_info __rcu *pr_dev_info __read_mostly;
+
+enum {
+ PAGE_REPORTING_IDLE = 0,
+ PAGE_REPORTING_REQUESTED,
+ PAGE_REPORTING_ACTIVE
+};
+
+/* request page reporting */
+static void
+__page_reporting_request(struct page_reporting_dev_info *prdev)
+{
+ unsigned int state;
+
+ /* Check to see if we are in desired state */
+ state = atomic_read(&prdev->state);
+ if (state == PAGE_REPORTING_REQUESTED)
+ return;
+
+ /*
+ * If reporting is already active there is nothing we need to do.
+ * Test against 0 as that represents PAGE_REPORTING_IDLE.
+ */
+ state = atomic_xchg(&prdev->state, PAGE_REPORTING_REQUESTED);
+ if (state != PAGE_REPORTING_IDLE)
+ return;
+
+ /*
+ * Delay the start of work to allow a sizable queue to build. For
+ * now we are limiting this to running no more than once every
+ * couple of seconds.
+ */
+ schedule_delayed_work(&prdev->work, PAGE_REPORTING_DELAY);
+}
+
+/* notify prdev of free page reporting request */
+void __page_reporting_notify(void)
+{
+ struct page_reporting_dev_info *prdev;
+
+ /*
+ * We use RCU to protect the pr_dev_info pointer. In almost all
+ * cases this should be present, however in the unlikely case of
+ * a shutdown this will be NULL and we should exit.
+ */
+ rcu_read_lock();
+ prdev = rcu_dereference(pr_dev_info);
+ if (likely(prdev))
+ __page_reporting_request(prdev);
+
+ rcu_read_unlock();
+}
+
+static void
+page_reporting_drain(struct page_reporting_dev_info *prdev,
+ struct scatterlist *sgl, unsigned int nents, bool reported)
+{
+ struct scatterlist *sg = sgl;
+
+ /*
+ * Drain the now reported pages back into their respective
+ * free lists/areas. We assume at least one page is populated.
+ */
+ do {
+ struct page *page = sg_page(sg);
+ int mt = get_pageblock_migratetype(page);
+ unsigned int order = get_order(sg->length);
+
+ __putback_isolated_page(page, order, mt);
+
+ /* If the pages were not reported due to error skip flagging */
+ if (!reported)
+ continue;
+
+ /*
+ * If page was not comingled with another page we can
+ * consider the result to be "reported" since the page
+ * hasn't been modified, otherwise we will need to
+ * report on the new larger page when we make our way
+ * up to that higher order.
+ */
+ if (PageBuddy(page) && buddy_order(page) == order)
+ __SetPageReported(page);
+ } while ((sg = sg_next(sg)));
+
+ /* reinitialize scatterlist now that it is empty */
+ sg_init_table(sgl, nents);
+}
+
+/*
+ * The page reporting cycle consists of 4 stages, fill, report, drain, and
+ * idle. We will cycle through the first 3 stages until we cannot obtain a
+ * full scatterlist of pages, in that case we will switch to idle.
+ */
+static int
+page_reporting_cycle(struct page_reporting_dev_info *prdev, struct zone *zone,
+ unsigned int order, unsigned int mt,
+ struct scatterlist *sgl, unsigned int *offset)
+{
+ struct free_area *area = &zone->free_area[order];
+ struct list_head *list = &area->free_list[mt];
+ unsigned int page_len = PAGE_SIZE << order;
+ struct page *page, *next;
+ long budget;
+ int err = 0;
+
+ /*
+ * Perform early check, if free area is empty there is
+ * nothing to process so we can skip this free_list.
+ */
+ if (list_empty(list))
+ return err;
+
+ spin_lock_irq(&zone->lock);
+
+ /*
+ * Limit how many calls we will be making to the page reporting
+ * device for this list. By doing this we avoid processing any
+ * given list for too long.
+ *
+ * The current value used allows us enough calls to process over a
+ * sixteenth of the current list plus one additional call to handle
+ * any pages that may have already been present from the previous
+ * list processed. This should result in us reporting all pages on
+ * an idle system in about 30 seconds.
+ *
+ * The division here should be cheap since PAGE_REPORTING_CAPACITY
+ * should always be a power of 2.
+ */
+ budget = DIV_ROUND_UP(area->nr_free, PAGE_REPORTING_CAPACITY * 16);
+
+ /* loop through free list adding unreported pages to sg list */
+ list_for_each_entry_safe(page, next, list, lru) {
+ /* We are going to skip over the reported pages. */
+ if (PageReported(page))
+ continue;
+
+ /*
+ * If we fully consumed our budget then update our
+ * state to indicate that we are requesting additional
+ * processing and exit this list.
+ */
+ if (budget < 0) {
+ atomic_set(&prdev->state, PAGE_REPORTING_REQUESTED);
+ next = page;
+ break;
+ }
+
+ /* Attempt to pull page from list and place in scatterlist */
+ if (*offset) {
+ if (!__isolate_free_page(page, order)) {
+ next = page;
+ break;
+ }
+
+ /* Add page to scatter list */
+ --(*offset);
+ sg_set_page(&sgl[*offset], page, page_len, 0);
+
+ continue;
+ }
+
+ /*
+ * Make the first non-reported page in the free list
+ * the new head of the free list before we release the
+ * zone lock.
+ */
+ if (!list_is_first(&page->lru, list))
+ list_rotate_to_front(&page->lru, list);
+
+ /* release lock before waiting on report processing */
+ spin_unlock_irq(&zone->lock);
+
+ /* begin processing pages in local list */
+ err = prdev->report(prdev, sgl, PAGE_REPORTING_CAPACITY);
+
+ /* reset offset since the full list was reported */
+ *offset = PAGE_REPORTING_CAPACITY;
+
+ /* update budget to reflect call to report function */
+ budget--;
+
+ /* reacquire zone lock and resume processing */
+ spin_lock_irq(&zone->lock);
+
+ /* flush reported pages from the sg list */
+ page_reporting_drain(prdev, sgl, PAGE_REPORTING_CAPACITY, !err);
+
+ /*
+ * Reset next to first entry, the old next isn't valid
+ * since we dropped the lock to report the pages
+ */
+ next = list_first_entry(list, struct page, lru);
+
+ /* exit on error */
+ if (err)
+ break;
+ }
+
+ /* Rotate any leftover pages to the head of the freelist */
+ if (!list_entry_is_head(next, list, lru) && !list_is_first(&next->lru, list))
+ list_rotate_to_front(&next->lru, list);
+
+ spin_unlock_irq(&zone->lock);
+
+ return err;
+}
+
+static int
+page_reporting_process_zone(struct page_reporting_dev_info *prdev,
+ struct scatterlist *sgl, struct zone *zone)
+{
+ unsigned int order, mt, leftover, offset = PAGE_REPORTING_CAPACITY;
+ unsigned long watermark;
+ int err = 0;
+
+ /* Generate minimum watermark to be able to guarantee progress */
+ watermark = low_wmark_pages(zone) +
+ (PAGE_REPORTING_CAPACITY << page_reporting_order);
+
+ /*
+ * Cancel request if insufficient free memory or if we failed
+ * to allocate page reporting statistics for the zone.
+ */
+ if (!zone_watermark_ok(zone, 0, watermark, 0, ALLOC_CMA))
+ return err;
+
+ /* Process each free list starting from lowest order/mt */
+ for (order = page_reporting_order; order < MAX_ORDER; order++) {
+ for (mt = 0; mt < MIGRATE_TYPES; mt++) {
+ /* We do not pull pages from the isolate free list */
+ if (is_migrate_isolate(mt))
+ continue;
+
+ err = page_reporting_cycle(prdev, zone, order, mt,
+ sgl, &offset);
+ if (err)
+ return err;
+ }
+ }
+
+ /* report the leftover pages before going idle */
+ leftover = PAGE_REPORTING_CAPACITY - offset;
+ if (leftover) {
+ sgl = &sgl[offset];
+ err = prdev->report(prdev, sgl, leftover);
+
+ /* flush any remaining pages out from the last report */
+ spin_lock_irq(&zone->lock);
+ page_reporting_drain(prdev, sgl, leftover, !err);
+ spin_unlock_irq(&zone->lock);
+ }
+
+ return err;
+}
+
+static void page_reporting_process(struct work_struct *work)
+{
+ struct delayed_work *d_work = to_delayed_work(work);
+ struct page_reporting_dev_info *prdev =
+ container_of(d_work, struct page_reporting_dev_info, work);
+ int err = 0, state = PAGE_REPORTING_ACTIVE;
+ struct scatterlist *sgl;
+ struct zone *zone;
+
+ /*
+ * Change the state to "Active" so that we can track if there is
+ * anyone requests page reporting after we complete our pass. If
+ * the state is not altered by the end of the pass we will switch
+ * to idle and quit scheduling reporting runs.
+ */
+ atomic_set(&prdev->state, state);
+
+ /* allocate scatterlist to store pages being reported on */
+ sgl = kmalloc_array(PAGE_REPORTING_CAPACITY, sizeof(*sgl), GFP_KERNEL);
+ if (!sgl)
+ goto err_out;
+
+ sg_init_table(sgl, PAGE_REPORTING_CAPACITY);
+
+ for_each_zone(zone) {
+ err = page_reporting_process_zone(prdev, sgl, zone);
+ if (err)
+ break;
+ }
+
+ kfree(sgl);
+err_out:
+ /*
+ * If the state has reverted back to requested then there may be
+ * additional pages to be processed. We will defer for 2s to allow
+ * more pages to accumulate.
+ */
+ state = atomic_cmpxchg(&prdev->state, state, PAGE_REPORTING_IDLE);
+ if (state == PAGE_REPORTING_REQUESTED)
+ schedule_delayed_work(&prdev->work, PAGE_REPORTING_DELAY);
+}
+
+static DEFINE_MUTEX(page_reporting_mutex);
+DEFINE_STATIC_KEY_FALSE(page_reporting_enabled);
+
+int page_reporting_register(struct page_reporting_dev_info *prdev)
+{
+ int err = 0;
+
+ mutex_lock(&page_reporting_mutex);
+
+ /* nothing to do if already in use */
+ if (rcu_access_pointer(pr_dev_info)) {
+ err = -EBUSY;
+ goto err_out;
+ }
+
+ /*
+ * If the page_reporting_order value is not set, we check if
+ * an order is provided from the driver that is performing the
+ * registration. If that is not provided either, we default to
+ * pageblock_order.
+ */
+
+ if (page_reporting_order == -1) {
+ if (prdev->order > 0 && prdev->order <= MAX_ORDER)
+ page_reporting_order = prdev->order;
+ else
+ page_reporting_order = pageblock_order;
+ }
+
+ /* initialize state and work structures */
+ atomic_set(&prdev->state, PAGE_REPORTING_IDLE);
+ INIT_DELAYED_WORK(&prdev->work, &page_reporting_process);
+
+ /* Begin initial flush of zones */
+ __page_reporting_request(prdev);
+
+ /* Assign device to allow notifications */
+ rcu_assign_pointer(pr_dev_info, prdev);
+
+ /* enable page reporting notification */
+ if (!static_key_enabled(&page_reporting_enabled)) {
+ static_branch_enable(&page_reporting_enabled);
+ pr_info("Free page reporting enabled\n");
+ }
+err_out:
+ mutex_unlock(&page_reporting_mutex);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(page_reporting_register);
+
+void page_reporting_unregister(struct page_reporting_dev_info *prdev)
+{
+ mutex_lock(&page_reporting_mutex);
+
+ if (rcu_access_pointer(pr_dev_info) == prdev) {
+ /* Disable page reporting notification */
+ RCU_INIT_POINTER(pr_dev_info, NULL);
+ synchronize_rcu();
+
+ /* Flush any existing work, and lock it out */
+ cancel_delayed_work_sync(&prdev->work);
+ }
+
+ mutex_unlock(&page_reporting_mutex);
+}
+EXPORT_SYMBOL_GPL(page_reporting_unregister);