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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/balloon_compaction.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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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/balloon_compaction.c')
-rw-r--r--mm/balloon_compaction.c258
1 files changed, 258 insertions, 0 deletions
diff --git a/mm/balloon_compaction.c b/mm/balloon_compaction.c
new file mode 100644
index 000000000..22c96fed7
--- /dev/null
+++ b/mm/balloon_compaction.c
@@ -0,0 +1,258 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * mm/balloon_compaction.c
+ *
+ * Common interface for making balloon pages movable by compaction.
+ *
+ * Copyright (C) 2012, Red Hat, Inc. Rafael Aquini <aquini@redhat.com>
+ */
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/export.h>
+#include <linux/balloon_compaction.h>
+
+static void balloon_page_enqueue_one(struct balloon_dev_info *b_dev_info,
+ struct page *page)
+{
+ /*
+ * Block others from accessing the 'page' when we get around to
+ * establishing additional references. We should be the only one
+ * holding a reference to the 'page' at this point. If we are not, then
+ * memory corruption is possible and we should stop execution.
+ */
+ BUG_ON(!trylock_page(page));
+ balloon_page_insert(b_dev_info, page);
+ unlock_page(page);
+ __count_vm_event(BALLOON_INFLATE);
+}
+
+/**
+ * balloon_page_list_enqueue() - inserts a list of pages into the balloon page
+ * list.
+ * @b_dev_info: balloon device descriptor where we will insert a new page to
+ * @pages: pages to enqueue - allocated using balloon_page_alloc.
+ *
+ * Driver must call this function to properly enqueue balloon pages before
+ * definitively removing them from the guest system.
+ *
+ * Return: number of pages that were enqueued.
+ */
+size_t balloon_page_list_enqueue(struct balloon_dev_info *b_dev_info,
+ struct list_head *pages)
+{
+ struct page *page, *tmp;
+ unsigned long flags;
+ size_t n_pages = 0;
+
+ spin_lock_irqsave(&b_dev_info->pages_lock, flags);
+ list_for_each_entry_safe(page, tmp, pages, lru) {
+ list_del(&page->lru);
+ balloon_page_enqueue_one(b_dev_info, page);
+ n_pages++;
+ }
+ spin_unlock_irqrestore(&b_dev_info->pages_lock, flags);
+ return n_pages;
+}
+EXPORT_SYMBOL_GPL(balloon_page_list_enqueue);
+
+/**
+ * balloon_page_list_dequeue() - removes pages from balloon's page list and
+ * returns a list of the pages.
+ * @b_dev_info: balloon device descriptor where we will grab a page from.
+ * @pages: pointer to the list of pages that would be returned to the caller.
+ * @n_req_pages: number of requested pages.
+ *
+ * Driver must call this function to properly de-allocate a previous enlisted
+ * balloon pages before definitively releasing it back to the guest system.
+ * This function tries to remove @n_req_pages from the ballooned pages and
+ * return them to the caller in the @pages list.
+ *
+ * Note that this function may fail to dequeue some pages even if the balloon
+ * isn't empty - since the page list can be temporarily empty due to compaction
+ * of isolated pages.
+ *
+ * Return: number of pages that were added to the @pages list.
+ */
+size_t balloon_page_list_dequeue(struct balloon_dev_info *b_dev_info,
+ struct list_head *pages, size_t n_req_pages)
+{
+ struct page *page, *tmp;
+ unsigned long flags;
+ size_t n_pages = 0;
+
+ spin_lock_irqsave(&b_dev_info->pages_lock, flags);
+ list_for_each_entry_safe(page, tmp, &b_dev_info->pages, lru) {
+ if (n_pages == n_req_pages)
+ break;
+
+ /*
+ * Block others from accessing the 'page' while we get around to
+ * establishing additional references and preparing the 'page'
+ * to be released by the balloon driver.
+ */
+ if (!trylock_page(page))
+ continue;
+
+ if (IS_ENABLED(CONFIG_BALLOON_COMPACTION) &&
+ PageIsolated(page)) {
+ /* raced with isolation */
+ unlock_page(page);
+ continue;
+ }
+ balloon_page_delete(page);
+ __count_vm_event(BALLOON_DEFLATE);
+ list_add(&page->lru, pages);
+ unlock_page(page);
+ n_pages++;
+ }
+ spin_unlock_irqrestore(&b_dev_info->pages_lock, flags);
+
+ return n_pages;
+}
+EXPORT_SYMBOL_GPL(balloon_page_list_dequeue);
+
+/*
+ * balloon_page_alloc - allocates a new page for insertion into the balloon
+ * page list.
+ *
+ * Driver must call this function to properly allocate a new balloon page.
+ * Driver must call balloon_page_enqueue before definitively removing the page
+ * from the guest system.
+ *
+ * Return: struct page for the allocated page or NULL on allocation failure.
+ */
+struct page *balloon_page_alloc(void)
+{
+ struct page *page = alloc_page(balloon_mapping_gfp_mask() |
+ __GFP_NOMEMALLOC | __GFP_NORETRY |
+ __GFP_NOWARN);
+ return page;
+}
+EXPORT_SYMBOL_GPL(balloon_page_alloc);
+
+/*
+ * balloon_page_enqueue - inserts a new page into the balloon page list.
+ *
+ * @b_dev_info: balloon device descriptor where we will insert a new page
+ * @page: new page to enqueue - allocated using balloon_page_alloc.
+ *
+ * Drivers must call this function to properly enqueue a new allocated balloon
+ * page before definitively removing the page from the guest system.
+ *
+ * Drivers must not call balloon_page_enqueue on pages that have been pushed to
+ * a list with balloon_page_push before removing them with balloon_page_pop. To
+ * enqueue a list of pages, use balloon_page_list_enqueue instead.
+ */
+void balloon_page_enqueue(struct balloon_dev_info *b_dev_info,
+ struct page *page)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&b_dev_info->pages_lock, flags);
+ balloon_page_enqueue_one(b_dev_info, page);
+ spin_unlock_irqrestore(&b_dev_info->pages_lock, flags);
+}
+EXPORT_SYMBOL_GPL(balloon_page_enqueue);
+
+/*
+ * balloon_page_dequeue - removes a page from balloon's page list and returns
+ * its address to allow the driver to release the page.
+ * @b_dev_info: balloon device descriptor where we will grab a page from.
+ *
+ * Driver must call this function to properly dequeue a previously enqueued page
+ * before definitively releasing it back to the guest system.
+ *
+ * Caller must perform its own accounting to ensure that this
+ * function is called only if some pages are actually enqueued.
+ *
+ * Note that this function may fail to dequeue some pages even if there are
+ * some enqueued pages - since the page list can be temporarily empty due to
+ * the compaction of isolated pages.
+ *
+ * TODO: remove the caller accounting requirements, and allow caller to wait
+ * until all pages can be dequeued.
+ *
+ * Return: struct page for the dequeued page, or NULL if no page was dequeued.
+ */
+struct page *balloon_page_dequeue(struct balloon_dev_info *b_dev_info)
+{
+ unsigned long flags;
+ LIST_HEAD(pages);
+ int n_pages;
+
+ n_pages = balloon_page_list_dequeue(b_dev_info, &pages, 1);
+
+ if (n_pages != 1) {
+ /*
+ * If we are unable to dequeue a balloon page because the page
+ * list is empty and there are no isolated pages, then something
+ * went out of track and some balloon pages are lost.
+ * BUG() here, otherwise the balloon driver may get stuck in
+ * an infinite loop while attempting to release all its pages.
+ */
+ spin_lock_irqsave(&b_dev_info->pages_lock, flags);
+ if (unlikely(list_empty(&b_dev_info->pages) &&
+ !b_dev_info->isolated_pages))
+ BUG();
+ spin_unlock_irqrestore(&b_dev_info->pages_lock, flags);
+ return NULL;
+ }
+ return list_first_entry(&pages, struct page, lru);
+}
+EXPORT_SYMBOL_GPL(balloon_page_dequeue);
+
+#ifdef CONFIG_BALLOON_COMPACTION
+
+static bool balloon_page_isolate(struct page *page, isolate_mode_t mode)
+
+{
+ struct balloon_dev_info *b_dev_info = balloon_page_device(page);
+ unsigned long flags;
+
+ spin_lock_irqsave(&b_dev_info->pages_lock, flags);
+ list_del(&page->lru);
+ b_dev_info->isolated_pages++;
+ spin_unlock_irqrestore(&b_dev_info->pages_lock, flags);
+
+ return true;
+}
+
+static void balloon_page_putback(struct page *page)
+{
+ struct balloon_dev_info *b_dev_info = balloon_page_device(page);
+ unsigned long flags;
+
+ spin_lock_irqsave(&b_dev_info->pages_lock, flags);
+ list_add(&page->lru, &b_dev_info->pages);
+ b_dev_info->isolated_pages--;
+ spin_unlock_irqrestore(&b_dev_info->pages_lock, flags);
+}
+
+/* move_to_new_page() counterpart for a ballooned page */
+static int balloon_page_migrate(struct page *newpage, struct page *page,
+ enum migrate_mode mode)
+{
+ struct balloon_dev_info *balloon = balloon_page_device(page);
+
+ /*
+ * We can not easily support the no copy case here so ignore it as it
+ * is unlikely to be used with balloon pages. See include/linux/hmm.h
+ * for a user of the MIGRATE_SYNC_NO_COPY mode.
+ */
+ if (mode == MIGRATE_SYNC_NO_COPY)
+ return -EINVAL;
+
+ VM_BUG_ON_PAGE(!PageLocked(page), page);
+ VM_BUG_ON_PAGE(!PageLocked(newpage), newpage);
+
+ return balloon->migratepage(balloon, newpage, page, mode);
+}
+
+const struct movable_operations balloon_mops = {
+ .migrate_page = balloon_page_migrate,
+ .isolate_page = balloon_page_isolate,
+ .putback_page = balloon_page_putback,
+};
+EXPORT_SYMBOL_GPL(balloon_mops);
+
+#endif /* CONFIG_BALLOON_COMPACTION */