From 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Tue, 21 Feb 2023 18:24:12 -0800 Subject: Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 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(). ... --- mm/list_lru.c | 605 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 605 insertions(+) create mode 100644 mm/list_lru.c (limited to 'mm/list_lru.c') diff --git a/mm/list_lru.c b/mm/list_lru.c new file mode 100644 index 000000000..a05e5bef3 --- /dev/null +++ b/mm/list_lru.c @@ -0,0 +1,605 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2013 Red Hat, Inc. and Parallels Inc. All rights reserved. + * Authors: David Chinner and Glauber Costa + * + * Generic LRU infrastructure + */ +#include +#include +#include +#include +#include +#include +#include +#include "slab.h" +#include "internal.h" + +#ifdef CONFIG_MEMCG_KMEM +static LIST_HEAD(memcg_list_lrus); +static DEFINE_MUTEX(list_lrus_mutex); + +static inline bool list_lru_memcg_aware(struct list_lru *lru) +{ + return lru->memcg_aware; +} + +static void list_lru_register(struct list_lru *lru) +{ + if (!list_lru_memcg_aware(lru)) + return; + + mutex_lock(&list_lrus_mutex); + list_add(&lru->list, &memcg_list_lrus); + mutex_unlock(&list_lrus_mutex); +} + +static void list_lru_unregister(struct list_lru *lru) +{ + if (!list_lru_memcg_aware(lru)) + return; + + mutex_lock(&list_lrus_mutex); + list_del(&lru->list); + mutex_unlock(&list_lrus_mutex); +} + +static int lru_shrinker_id(struct list_lru *lru) +{ + return lru->shrinker_id; +} + +static inline struct list_lru_one * +list_lru_from_memcg_idx(struct list_lru *lru, int nid, int idx) +{ + if (list_lru_memcg_aware(lru) && idx >= 0) { + struct list_lru_memcg *mlru = xa_load(&lru->xa, idx); + + return mlru ? &mlru->node[nid] : NULL; + } + return &lru->node[nid].lru; +} + +static inline struct list_lru_one * +list_lru_from_kmem(struct list_lru *lru, int nid, void *ptr, + struct mem_cgroup **memcg_ptr) +{ + struct list_lru_node *nlru = &lru->node[nid]; + struct list_lru_one *l = &nlru->lru; + struct mem_cgroup *memcg = NULL; + + if (!list_lru_memcg_aware(lru)) + goto out; + + memcg = mem_cgroup_from_slab_obj(ptr); + if (!memcg) + goto out; + + l = list_lru_from_memcg_idx(lru, nid, memcg_kmem_id(memcg)); +out: + if (memcg_ptr) + *memcg_ptr = memcg; + return l; +} +#else +static void list_lru_register(struct list_lru *lru) +{ +} + +static void list_lru_unregister(struct list_lru *lru) +{ +} + +static int lru_shrinker_id(struct list_lru *lru) +{ + return -1; +} + +static inline bool list_lru_memcg_aware(struct list_lru *lru) +{ + return false; +} + +static inline struct list_lru_one * +list_lru_from_memcg_idx(struct list_lru *lru, int nid, int idx) +{ + return &lru->node[nid].lru; +} + +static inline struct list_lru_one * +list_lru_from_kmem(struct list_lru *lru, int nid, void *ptr, + struct mem_cgroup **memcg_ptr) +{ + if (memcg_ptr) + *memcg_ptr = NULL; + return &lru->node[nid].lru; +} +#endif /* CONFIG_MEMCG_KMEM */ + +bool list_lru_add(struct list_lru *lru, struct list_head *item) +{ + int nid = page_to_nid(virt_to_page(item)); + struct list_lru_node *nlru = &lru->node[nid]; + struct mem_cgroup *memcg; + struct list_lru_one *l; + + spin_lock(&nlru->lock); + if (list_empty(item)) { + l = list_lru_from_kmem(lru, nid, item, &memcg); + list_add_tail(item, &l->list); + /* Set shrinker bit if the first element was added */ + if (!l->nr_items++) + set_shrinker_bit(memcg, nid, + lru_shrinker_id(lru)); + nlru->nr_items++; + spin_unlock(&nlru->lock); + return true; + } + spin_unlock(&nlru->lock); + return false; +} +EXPORT_SYMBOL_GPL(list_lru_add); + +bool list_lru_del(struct list_lru *lru, struct list_head *item) +{ + int nid = page_to_nid(virt_to_page(item)); + struct list_lru_node *nlru = &lru->node[nid]; + struct list_lru_one *l; + + spin_lock(&nlru->lock); + if (!list_empty(item)) { + l = list_lru_from_kmem(lru, nid, item, NULL); + list_del_init(item); + l->nr_items--; + nlru->nr_items--; + spin_unlock(&nlru->lock); + return true; + } + spin_unlock(&nlru->lock); + return false; +} +EXPORT_SYMBOL_GPL(list_lru_del); + +void list_lru_isolate(struct list_lru_one *list, struct list_head *item) +{ + list_del_init(item); + list->nr_items--; +} +EXPORT_SYMBOL_GPL(list_lru_isolate); + +void list_lru_isolate_move(struct list_lru_one *list, struct list_head *item, + struct list_head *head) +{ + list_move(item, head); + list->nr_items--; +} +EXPORT_SYMBOL_GPL(list_lru_isolate_move); + +unsigned long list_lru_count_one(struct list_lru *lru, + int nid, struct mem_cgroup *memcg) +{ + struct list_lru_one *l; + long count; + + rcu_read_lock(); + l = list_lru_from_memcg_idx(lru, nid, memcg_kmem_id(memcg)); + count = l ? READ_ONCE(l->nr_items) : 0; + rcu_read_unlock(); + + if (unlikely(count < 0)) + count = 0; + + return count; +} +EXPORT_SYMBOL_GPL(list_lru_count_one); + +unsigned long list_lru_count_node(struct list_lru *lru, int nid) +{ + struct list_lru_node *nlru; + + nlru = &lru->node[nid]; + return nlru->nr_items; +} +EXPORT_SYMBOL_GPL(list_lru_count_node); + +static unsigned long +__list_lru_walk_one(struct list_lru *lru, int nid, int memcg_idx, + list_lru_walk_cb isolate, void *cb_arg, + unsigned long *nr_to_walk) +{ + struct list_lru_node *nlru = &lru->node[nid]; + struct list_lru_one *l; + struct list_head *item, *n; + unsigned long isolated = 0; + +restart: + l = list_lru_from_memcg_idx(lru, nid, memcg_idx); + if (!l) + goto out; + + list_for_each_safe(item, n, &l->list) { + enum lru_status ret; + + /* + * decrement nr_to_walk first so that we don't livelock if we + * get stuck on large numbers of LRU_RETRY items + */ + if (!*nr_to_walk) + break; + --*nr_to_walk; + + ret = isolate(item, l, &nlru->lock, cb_arg); + switch (ret) { + case LRU_REMOVED_RETRY: + assert_spin_locked(&nlru->lock); + fallthrough; + case LRU_REMOVED: + isolated++; + nlru->nr_items--; + /* + * If the lru lock has been dropped, our list + * traversal is now invalid and so we have to + * restart from scratch. + */ + if (ret == LRU_REMOVED_RETRY) + goto restart; + break; + case LRU_ROTATE: + list_move_tail(item, &l->list); + break; + case LRU_SKIP: + break; + case LRU_RETRY: + /* + * The lru lock has been dropped, our list traversal is + * now invalid and so we have to restart from scratch. + */ + assert_spin_locked(&nlru->lock); + goto restart; + default: + BUG(); + } + } +out: + return isolated; +} + +unsigned long +list_lru_walk_one(struct list_lru *lru, int nid, struct mem_cgroup *memcg, + list_lru_walk_cb isolate, void *cb_arg, + unsigned long *nr_to_walk) +{ + struct list_lru_node *nlru = &lru->node[nid]; + unsigned long ret; + + spin_lock(&nlru->lock); + ret = __list_lru_walk_one(lru, nid, memcg_kmem_id(memcg), isolate, + cb_arg, nr_to_walk); + spin_unlock(&nlru->lock); + return ret; +} +EXPORT_SYMBOL_GPL(list_lru_walk_one); + +unsigned long +list_lru_walk_one_irq(struct list_lru *lru, int nid, struct mem_cgroup *memcg, + list_lru_walk_cb isolate, void *cb_arg, + unsigned long *nr_to_walk) +{ + struct list_lru_node *nlru = &lru->node[nid]; + unsigned long ret; + + spin_lock_irq(&nlru->lock); + ret = __list_lru_walk_one(lru, nid, memcg_kmem_id(memcg), isolate, + cb_arg, nr_to_walk); + spin_unlock_irq(&nlru->lock); + return ret; +} + +unsigned long list_lru_walk_node(struct list_lru *lru, int nid, + list_lru_walk_cb isolate, void *cb_arg, + unsigned long *nr_to_walk) +{ + long isolated = 0; + + isolated += list_lru_walk_one(lru, nid, NULL, isolate, cb_arg, + nr_to_walk); + +#ifdef CONFIG_MEMCG_KMEM + if (*nr_to_walk > 0 && list_lru_memcg_aware(lru)) { + struct list_lru_memcg *mlru; + unsigned long index; + + xa_for_each(&lru->xa, index, mlru) { + struct list_lru_node *nlru = &lru->node[nid]; + + spin_lock(&nlru->lock); + isolated += __list_lru_walk_one(lru, nid, index, + isolate, cb_arg, + nr_to_walk); + spin_unlock(&nlru->lock); + + if (*nr_to_walk <= 0) + break; + } + } +#endif + + return isolated; +} +EXPORT_SYMBOL_GPL(list_lru_walk_node); + +static void init_one_lru(struct list_lru_one *l) +{ + INIT_LIST_HEAD(&l->list); + l->nr_items = 0; +} + +#ifdef CONFIG_MEMCG_KMEM +static struct list_lru_memcg *memcg_init_list_lru_one(gfp_t gfp) +{ + int nid; + struct list_lru_memcg *mlru; + + mlru = kmalloc(struct_size(mlru, node, nr_node_ids), gfp); + if (!mlru) + return NULL; + + for_each_node(nid) + init_one_lru(&mlru->node[nid]); + + return mlru; +} + +static void memcg_list_lru_free(struct list_lru *lru, int src_idx) +{ + struct list_lru_memcg *mlru = xa_erase_irq(&lru->xa, src_idx); + + /* + * The __list_lru_walk_one() can walk the list of this node. + * We need kvfree_rcu() here. And the walking of the list + * is under lru->node[nid]->lock, which can serve as a RCU + * read-side critical section. + */ + if (mlru) + kvfree_rcu(mlru, rcu); +} + +static inline void memcg_init_list_lru(struct list_lru *lru, bool memcg_aware) +{ + if (memcg_aware) + xa_init_flags(&lru->xa, XA_FLAGS_LOCK_IRQ); + lru->memcg_aware = memcg_aware; +} + +static void memcg_destroy_list_lru(struct list_lru *lru) +{ + XA_STATE(xas, &lru->xa, 0); + struct list_lru_memcg *mlru; + + if (!list_lru_memcg_aware(lru)) + return; + + xas_lock_irq(&xas); + xas_for_each(&xas, mlru, ULONG_MAX) { + kfree(mlru); + xas_store(&xas, NULL); + } + xas_unlock_irq(&xas); +} + +static void memcg_reparent_list_lru_node(struct list_lru *lru, int nid, + int src_idx, struct mem_cgroup *dst_memcg) +{ + struct list_lru_node *nlru = &lru->node[nid]; + int dst_idx = dst_memcg->kmemcg_id; + struct list_lru_one *src, *dst; + + /* + * Since list_lru_{add,del} may be called under an IRQ-safe lock, + * we have to use IRQ-safe primitives here to avoid deadlock. + */ + spin_lock_irq(&nlru->lock); + + src = list_lru_from_memcg_idx(lru, nid, src_idx); + if (!src) + goto out; + dst = list_lru_from_memcg_idx(lru, nid, dst_idx); + + list_splice_init(&src->list, &dst->list); + + if (src->nr_items) { + dst->nr_items += src->nr_items; + set_shrinker_bit(dst_memcg, nid, lru_shrinker_id(lru)); + src->nr_items = 0; + } +out: + spin_unlock_irq(&nlru->lock); +} + +static void memcg_reparent_list_lru(struct list_lru *lru, + int src_idx, struct mem_cgroup *dst_memcg) +{ + int i; + + for_each_node(i) + memcg_reparent_list_lru_node(lru, i, src_idx, dst_memcg); + + memcg_list_lru_free(lru, src_idx); +} + +void memcg_reparent_list_lrus(struct mem_cgroup *memcg, struct mem_cgroup *parent) +{ + struct cgroup_subsys_state *css; + struct list_lru *lru; + int src_idx = memcg->kmemcg_id; + + /* + * Change kmemcg_id of this cgroup and all its descendants to the + * parent's id, and then move all entries from this cgroup's list_lrus + * to ones of the parent. + * + * After we have finished, all list_lrus corresponding to this cgroup + * are guaranteed to remain empty. So we can safely free this cgroup's + * list lrus in memcg_list_lru_free(). + * + * Changing ->kmemcg_id to the parent can prevent memcg_list_lru_alloc() + * from allocating list lrus for this cgroup after memcg_list_lru_free() + * call. + */ + rcu_read_lock(); + css_for_each_descendant_pre(css, &memcg->css) { + struct mem_cgroup *child; + + child = mem_cgroup_from_css(css); + WRITE_ONCE(child->kmemcg_id, parent->kmemcg_id); + } + rcu_read_unlock(); + + mutex_lock(&list_lrus_mutex); + list_for_each_entry(lru, &memcg_list_lrus, list) + memcg_reparent_list_lru(lru, src_idx, parent); + mutex_unlock(&list_lrus_mutex); +} + +static inline bool memcg_list_lru_allocated(struct mem_cgroup *memcg, + struct list_lru *lru) +{ + int idx = memcg->kmemcg_id; + + return idx < 0 || xa_load(&lru->xa, idx); +} + +int memcg_list_lru_alloc(struct mem_cgroup *memcg, struct list_lru *lru, + gfp_t gfp) +{ + int i; + unsigned long flags; + struct list_lru_memcg_table { + struct list_lru_memcg *mlru; + struct mem_cgroup *memcg; + } *table; + XA_STATE(xas, &lru->xa, 0); + + if (!list_lru_memcg_aware(lru) || memcg_list_lru_allocated(memcg, lru)) + return 0; + + gfp &= GFP_RECLAIM_MASK; + table = kmalloc_array(memcg->css.cgroup->level, sizeof(*table), gfp); + if (!table) + return -ENOMEM; + + /* + * Because the list_lru can be reparented to the parent cgroup's + * list_lru, we should make sure that this cgroup and all its + * ancestors have allocated list_lru_memcg. + */ + for (i = 0; memcg; memcg = parent_mem_cgroup(memcg), i++) { + if (memcg_list_lru_allocated(memcg, lru)) + break; + + table[i].memcg = memcg; + table[i].mlru = memcg_init_list_lru_one(gfp); + if (!table[i].mlru) { + while (i--) + kfree(table[i].mlru); + kfree(table); + return -ENOMEM; + } + } + + xas_lock_irqsave(&xas, flags); + while (i--) { + int index = READ_ONCE(table[i].memcg->kmemcg_id); + struct list_lru_memcg *mlru = table[i].mlru; + + xas_set(&xas, index); +retry: + if (unlikely(index < 0 || xas_error(&xas) || xas_load(&xas))) { + kfree(mlru); + } else { + xas_store(&xas, mlru); + if (xas_error(&xas) == -ENOMEM) { + xas_unlock_irqrestore(&xas, flags); + if (xas_nomem(&xas, gfp)) + xas_set_err(&xas, 0); + xas_lock_irqsave(&xas, flags); + /* + * The xas lock has been released, this memcg + * can be reparented before us. So reload + * memcg id. More details see the comments + * in memcg_reparent_list_lrus(). + */ + index = READ_ONCE(table[i].memcg->kmemcg_id); + if (index < 0) + xas_set_err(&xas, 0); + else if (!xas_error(&xas) && index != xas.xa_index) + xas_set(&xas, index); + goto retry; + } + } + } + /* xas_nomem() is used to free memory instead of memory allocation. */ + if (xas.xa_alloc) + xas_nomem(&xas, gfp); + xas_unlock_irqrestore(&xas, flags); + kfree(table); + + return xas_error(&xas); +} +#else +static inline void memcg_init_list_lru(struct list_lru *lru, bool memcg_aware) +{ +} + +static void memcg_destroy_list_lru(struct list_lru *lru) +{ +} +#endif /* CONFIG_MEMCG_KMEM */ + +int __list_lru_init(struct list_lru *lru, bool memcg_aware, + struct lock_class_key *key, struct shrinker *shrinker) +{ + int i; + +#ifdef CONFIG_MEMCG_KMEM + if (shrinker) + lru->shrinker_id = shrinker->id; + else + lru->shrinker_id = -1; +#endif + + lru->node = kcalloc(nr_node_ids, sizeof(*lru->node), GFP_KERNEL); + if (!lru->node) + return -ENOMEM; + + for_each_node(i) { + spin_lock_init(&lru->node[i].lock); + if (key) + lockdep_set_class(&lru->node[i].lock, key); + init_one_lru(&lru->node[i].lru); + } + + memcg_init_list_lru(lru, memcg_aware); + list_lru_register(lru); + + return 0; +} +EXPORT_SYMBOL_GPL(__list_lru_init); + +void list_lru_destroy(struct list_lru *lru) +{ + /* Already destroyed or not yet initialized? */ + if (!lru->node) + return; + + list_lru_unregister(lru); + + memcg_destroy_list_lru(lru); + kfree(lru->node); + lru->node = NULL; + +#ifdef CONFIG_MEMCG_KMEM + lru->shrinker_id = -1; +#endif +} +EXPORT_SYMBOL_GPL(list_lru_destroy); -- cgit v1.2.3