OSCL-LXR linux-6.0.1/​include/​linux/​memcontrol.h	Source navigation Diff markup Identifier search General search
	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 /* SPDX-License-Identifier: GPL-2.0-or-later */
 /* memcontrol.h - Memory Controller
  *
  * Copyright IBM Corporation, 2007
  * Author Balbir Singh <balbir@linux.vnet.ibm.com>
  *
  * Copyright 2007 OpenVZ SWsoft Inc
  * Author: Pavel Emelianov <xemul@openvz.org>
  */
 
 #ifndef _LINUX_MEMCONTROL_H
 #define _LINUX_MEMCONTROL_H
 #include <linux/cgroup.h>
 #include <linux/vm_event_item.h>
 #include <linux/hardirq.h>
 #include <linux/jump_label.h>
 #include <linux/page_counter.h>
 #include <linux/vmpressure.h>
 #include <linux/eventfd.h>
 #include <linux/mm.h>
 #include <linux/vmstat.h>
 #include <linux/writeback.h>
 #include <linux/page-flags.h>
 
 struct mem_cgroup;
 struct obj_cgroup;
 struct page;
 struct mm_struct;
 struct kmem_cache;
 
 /* Cgroup-specific page state, on top of universal node page state */
 enum memcg_stat_item {
     MEMCG_SWAP = NR_VM_NODE_STAT_ITEMS,
     MEMCG_SOCK,
     MEMCG_PERCPU_B,
     MEMCG_VMALLOC,
     MEMCG_KMEM,
     MEMCG_ZSWAP_B,
     MEMCG_ZSWAPPED,
     MEMCG_NR_STAT,
 };
 
 enum memcg_memory_event {
     MEMCG_LOW,
     MEMCG_HIGH,
     MEMCG_MAX,
     MEMCG_OOM,
     MEMCG_OOM_KILL,
     MEMCG_OOM_GROUP_KILL,
     MEMCG_SWAP_HIGH,
     MEMCG_SWAP_MAX,
     MEMCG_SWAP_FAIL,
     MEMCG_NR_MEMORY_EVENTS,
 };
 
 struct mem_cgroup_reclaim_cookie {
     pg_data_t *pgdat;
     unsigned int generation;
 };
 
 #ifdef CONFIG_MEMCG
 
 #define MEM_CGROUP_ID_SHIFT 16
 #define MEM_CGROUP_ID_MAX   USHRT_MAX
 
 struct mem_cgroup_id {
     int id;
     refcount_t ref;
 };
 
 /*
  * Per memcg event counter is incremented at every pagein/pageout. With THP,
  * it will be incremented by the number of pages. This counter is used
  * to trigger some periodic events. This is straightforward and better
  * than using jiffies etc. to handle periodic memcg event.
  */
 enum mem_cgroup_events_target {
     MEM_CGROUP_TARGET_THRESH,
     MEM_CGROUP_TARGET_SOFTLIMIT,
     MEM_CGROUP_NTARGETS,
 };
 
 struct memcg_vmstats_percpu {
     /* Local (CPU and cgroup) page state & events */
     long            state[MEMCG_NR_STAT];
     unsigned long       events[NR_VM_EVENT_ITEMS];
 
     /* Delta calculation for lockless upward propagation */
     long            state_prev[MEMCG_NR_STAT];
     unsigned long       events_prev[NR_VM_EVENT_ITEMS];
 
     /* Cgroup1: threshold notifications & softlimit tree updates */
     unsigned long       nr_page_events;
     unsigned long       targets[MEM_CGROUP_NTARGETS];
 };
 
 struct memcg_vmstats {
     /* Aggregated (CPU and subtree) page state & events */
     long            state[MEMCG_NR_STAT];
     unsigned long       events[NR_VM_EVENT_ITEMS];
 
     /* Pending child counts during tree propagation */
     long            state_pending[MEMCG_NR_STAT];
     unsigned long       events_pending[NR_VM_EVENT_ITEMS];
 };
 
 struct mem_cgroup_reclaim_iter {
     struct mem_cgroup *position;
     /* scan generation, increased every round-trip */
     unsigned int generation;
 };
 
 /*
  * Bitmap and deferred work of shrinker::id corresponding to memcg-aware
  * shrinkers, which have elements charged to this memcg.
  */
 struct shrinker_info {
     struct rcu_head rcu;
     atomic_long_t *nr_deferred;
     unsigned long *map;
 };
 
 struct lruvec_stats_percpu {
     /* Local (CPU and cgroup) state */
     long state[NR_VM_NODE_STAT_ITEMS];
 
     /* Delta calculation for lockless upward propagation */
     long state_prev[NR_VM_NODE_STAT_ITEMS];
 };
 
 struct lruvec_stats {
     /* Aggregated (CPU and subtree) state */
     long state[NR_VM_NODE_STAT_ITEMS];
 
     /* Pending child counts during tree propagation */
     long state_pending[NR_VM_NODE_STAT_ITEMS];
 };
 
 /*
  * per-node information in memory controller.
  */
 struct mem_cgroup_per_node {
     struct lruvec       lruvec;
 
     struct lruvec_stats_percpu __percpu *lruvec_stats_percpu;
     struct lruvec_stats         lruvec_stats;
 
     unsigned long       lru_zone_size[MAX_NR_ZONES][NR_LRU_LISTS];
 
     struct mem_cgroup_reclaim_iter  iter;
 
     struct shrinker_info __rcu  *shrinker_info;
 
     struct rb_node      tree_node;  /* RB tree node */
     unsigned long       usage_in_excess;/* Set to the value by which */
                         /* the soft limit is exceeded*/
     bool            on_tree;
     struct mem_cgroup   *memcg;     /* Back pointer, we cannot */
                         /* use container_of    */
 };
 
 struct mem_cgroup_threshold {
     struct eventfd_ctx *eventfd;
     unsigned long threshold;
 };
 
 /* For threshold */
 struct mem_cgroup_threshold_ary {
     /* An array index points to threshold just below or equal to usage. */
     int current_threshold;
     /* Size of entries[] */
     unsigned int size;
     /* Array of thresholds */
     struct mem_cgroup_threshold entries[];
 };
 
 struct mem_cgroup_thresholds {
     /* Primary thresholds array */
     struct mem_cgroup_threshold_ary *primary;
     /*
      * Spare threshold array.
      * This is needed to make mem_cgroup_unregister_event() "never fail".
      * It must be able to store at least primary->size - 1 entries.
      */
     struct mem_cgroup_threshold_ary *spare;
 };
 
 #if defined(CONFIG_SMP)
 struct memcg_padding {
     char x[0];
 } ____cacheline_internodealigned_in_smp;
 #define MEMCG_PADDING(name)      struct memcg_padding name
 #else
 #define MEMCG_PADDING(name)
 #endif
 
 /*
  * Remember four most recent foreign writebacks with dirty pages in this
  * cgroup.  Inode sharing is expected to be uncommon and, even if we miss
  * one in a given round, we're likely to catch it later if it keeps
  * foreign-dirtying, so a fairly low count should be enough.
  *
  * See mem_cgroup_track_foreign_dirty_slowpath() for details.
  */
 #define MEMCG_CGWB_FRN_CNT  4
 
 struct memcg_cgwb_frn {
     u64 bdi_id;         /* bdi->id of the foreign inode */
     int memcg_id;           /* memcg->css.id of foreign inode */
     u64 at;             /* jiffies_64 at the time of dirtying */
     struct wb_completion done;  /* tracks in-flight foreign writebacks */
 };
 
 /*
  * Bucket for arbitrarily byte-sized objects charged to a memory
  * cgroup. The bucket can be reparented in one piece when the cgroup
  * is destroyed, without having to round up the individual references
  * of all live memory objects in the wild.
  */
 struct obj_cgroup {
     struct percpu_ref refcnt;
     struct mem_cgroup *memcg;
     atomic_t nr_charged_bytes;
     union {
         struct list_head list; /* protected by objcg_lock */
         struct rcu_head rcu;
     };
 };
 
 /*
  * The memory controller data structure. The memory controller controls both
  * page cache and RSS per cgroup. We would eventually like to provide
  * statistics based on the statistics developed by Rik Van Riel for clock-pro,
  * to help the administrator determine what knobs to tune.
  */
 struct mem_cgroup {
     struct cgroup_subsys_state css;
 
     /* Private memcg ID. Used to ID objects that outlive the cgroup */
     struct mem_cgroup_id id;
 
     /* Accounted resources */
     struct page_counter memory;     /* Both v1 & v2 */
 
     union {
         struct page_counter swap;   /* v2 only */
         struct page_counter memsw;  /* v1 only */
     };
 
     /* Legacy consumer-oriented counters */
     struct page_counter kmem;       /* v1 only */
     struct page_counter tcpmem;     /* v1 only */
 
     /* Range enforcement for interrupt charges */
     struct work_struct high_work;
 
 #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP)
     unsigned long zswap_max;
 #endif
 
     unsigned long soft_limit;
 
     /* vmpressure notifications */
     struct vmpressure vmpressure;
 
     /*
      * Should the OOM killer kill all belonging tasks, had it kill one?
      */
     bool oom_group;
 
     /* protected by memcg_oom_lock */
     bool        oom_lock;
     int     under_oom;
 
     int swappiness;
     /* OOM-Killer disable */
     int     oom_kill_disable;
 
     /* memory.events and memory.events.local */
     struct cgroup_file events_file;
     struct cgroup_file events_local_file;
 
     /* handle for "memory.swap.events" */
     struct cgroup_file swap_events_file;
 
     /* protect arrays of thresholds */
     struct mutex thresholds_lock;
 
     /* thresholds for memory usage. RCU-protected */
     struct mem_cgroup_thresholds thresholds;
 
     /* thresholds for mem+swap usage. RCU-protected */
     struct mem_cgroup_thresholds memsw_thresholds;
 
     /* For oom notifier event fd */
     struct list_head oom_notify;
 
     /*
      * Should we move charges of a task when a task is moved into this
      * mem_cgroup ? And what type of charges should we move ?
      */
     unsigned long move_charge_at_immigrate;
     /* taken only while moving_account > 0 */
     spinlock_t      move_lock;
     unsigned long       move_lock_flags;
 
     MEMCG_PADDING(_pad1_);
 
     /* memory.stat */
     struct memcg_vmstats    vmstats;
 
     /* memory.events */
     atomic_long_t       memory_events[MEMCG_NR_MEMORY_EVENTS];
     atomic_long_t       memory_events_local[MEMCG_NR_MEMORY_EVENTS];
 
     unsigned long       socket_pressure;
 
     /* Legacy tcp memory accounting */
     bool            tcpmem_active;
     int         tcpmem_pressure;
 
 #ifdef CONFIG_MEMCG_KMEM
     int kmemcg_id;
     struct obj_cgroup __rcu *objcg;
     /* list of inherited objcgs, protected by objcg_lock */
     struct list_head objcg_list;
 #endif
 
     MEMCG_PADDING(_pad2_);
 
     /*
      * set > 0 if pages under this cgroup are moving to other cgroup.
      */
     atomic_t        moving_account;
     struct task_struct  *move_lock_task;
 
     struct memcg_vmstats_percpu __percpu *vmstats_percpu;
 
 #ifdef CONFIG_CGROUP_WRITEBACK
     struct list_head cgwb_list;
     struct wb_domain cgwb_domain;
     struct memcg_cgwb_frn cgwb_frn[MEMCG_CGWB_FRN_CNT];
 #endif
 
     /* List of events which userspace want to receive */
     struct list_head event_list;
     spinlock_t event_list_lock;
 
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
     struct deferred_split deferred_split_queue;
 #endif
 
     struct mem_cgroup_per_node *nodeinfo[];
 };
 
 /*
  * size of first charge trial. "32" comes from vmscan.c's magic value.
  * TODO: maybe necessary to use big numbers in big irons.
  */
 #define MEMCG_CHARGE_BATCH 32U
 
 extern struct mem_cgroup *root_mem_cgroup;
 
 enum page_memcg_data_flags {
     /* page->memcg_data is a pointer to an objcgs vector */
     MEMCG_DATA_OBJCGS = (1UL << 0),
     /* page has been accounted as a non-slab kernel page */
     MEMCG_DATA_KMEM = (1UL << 1),
     /* the next bit after the last actual flag */
     __NR_MEMCG_DATA_FLAGS  = (1UL << 2),
 };
 
 #define MEMCG_DATA_FLAGS_MASK (__NR_MEMCG_DATA_FLAGS - 1)
 
 static inline bool folio_memcg_kmem(struct folio *folio);
 
 /*
  * After the initialization objcg->memcg is always pointing at
  * a valid memcg, but can be atomically swapped to the parent memcg.
  *
  * The caller must ensure that the returned memcg won't be released:
  * e.g. acquire the rcu_read_lock or css_set_lock.
  */
 static inline struct mem_cgroup *obj_cgroup_memcg(struct obj_cgroup *objcg)
 {
     return READ_ONCE(objcg->memcg);
 }
 
 /*
  * __folio_memcg - Get the memory cgroup associated with a non-kmem folio
  * @folio: Pointer to the folio.
  *
  * Returns a pointer to the memory cgroup associated with the folio,
  * or NULL. This function assumes that the folio is known to have a
  * proper memory cgroup pointer. It's not safe to call this function
  * against some type of folios, e.g. slab folios or ex-slab folios or
  * kmem folios.
  */
 static inline struct mem_cgroup *__folio_memcg(struct folio *folio)
 {
     unsigned long memcg_data = folio->memcg_data;
 
     VM_BUG_ON_FOLIO(folio_test_slab(folio), folio);
     VM_BUG_ON_FOLIO(memcg_data & MEMCG_DATA_OBJCGS, folio);
     VM_BUG_ON_FOLIO(memcg_data & MEMCG_DATA_KMEM, folio);
 
     return (struct mem_cgroup *)(memcg_data & ~MEMCG_DATA_FLAGS_MASK);
 }
 
 /*
  * __folio_objcg - get the object cgroup associated with a kmem folio.
  * @folio: Pointer to the folio.
  *
  * Returns a pointer to the object cgroup associated with the folio,
  * or NULL. This function assumes that the folio is known to have a
  * proper object cgroup pointer. It's not safe to call this function
  * against some type of folios, e.g. slab folios or ex-slab folios or
  * LRU folios.
  */
 static inline struct obj_cgroup *__folio_objcg(struct folio *folio)
 {
     unsigned long memcg_data = folio->memcg_data;
 
     VM_BUG_ON_FOLIO(folio_test_slab(folio), folio);
     VM_BUG_ON_FOLIO(memcg_data & MEMCG_DATA_OBJCGS, folio);
     VM_BUG_ON_FOLIO(!(memcg_data & MEMCG_DATA_KMEM), folio);
 
     return (struct obj_cgroup *)(memcg_data & ~MEMCG_DATA_FLAGS_MASK);
 }
 
 /*
  * folio_memcg - Get the memory cgroup associated with a folio.
  * @folio: Pointer to the folio.
  *
  * Returns a pointer to the memory cgroup associated with the folio,
  * or NULL. This function assumes that the folio is known to have a
  * proper memory cgroup pointer. It's not safe to call this function
  * against some type of folios, e.g. slab folios or ex-slab folios.
  *
  * For a non-kmem folio any of the following ensures folio and memcg binding
  * stability:
  *
  * - the folio lock
  * - LRU isolation
  * - lock_page_memcg()
  * - exclusive reference
  *
  * For a kmem folio a caller should hold an rcu read lock to protect memcg
  * associated with a kmem folio from being released.
  */
 static inline struct mem_cgroup *folio_memcg(struct folio *folio)
 {
     if (folio_memcg_kmem(folio))
         return obj_cgroup_memcg(__folio_objcg(folio));
     return __folio_memcg(folio);
 }
 
 static inline struct mem_cgroup *page_memcg(struct page *page)
 {
     return folio_memcg(page_folio(page));
 }
 
 /**
  * folio_memcg_rcu - Locklessly get the memory cgroup associated with a folio.
  * @folio: Pointer to the folio.
  *
  * This function assumes that the folio is known to have a
  * proper memory cgroup pointer. It's not safe to call this function
  * against some type of folios, e.g. slab folios or ex-slab folios.
  *
  * Return: A pointer to the memory cgroup associated with the folio,
  * or NULL.
  */
 static inline struct mem_cgroup *folio_memcg_rcu(struct folio *folio)
 {
     unsigned long memcg_data = READ_ONCE(folio->memcg_data);
 
     VM_BUG_ON_FOLIO(folio_test_slab(folio), folio);
     WARN_ON_ONCE(!rcu_read_lock_held());
 
     if (memcg_data & MEMCG_DATA_KMEM) {
         struct obj_cgroup *objcg;
 
         objcg = (void *)(memcg_data & ~MEMCG_DATA_FLAGS_MASK);
         return obj_cgroup_memcg(objcg);
     }
 
     return (struct mem_cgroup *)(memcg_data & ~MEMCG_DATA_FLAGS_MASK);
 }
 
 /*
  * page_memcg_check - get the memory cgroup associated with a page
  * @page: a pointer to the page struct
  *
  * Returns a pointer to the memory cgroup associated with the page,
  * or NULL. This function unlike page_memcg() can take any page
  * as an argument. It has to be used in cases when it's not known if a page
  * has an associated memory cgroup pointer or an object cgroups vector or
  * an object cgroup.
  *
  * For a non-kmem page any of the following ensures page and memcg binding
  * stability:
  *
  * - the page lock
  * - LRU isolation
  * - lock_page_memcg()
  * - exclusive reference
  *
  * For a kmem page a caller should hold an rcu read lock to protect memcg
  * associated with a kmem page from being released.
  */
 static inline struct mem_cgroup *page_memcg_check(struct page *page)
 {
     /*
      * Because page->memcg_data might be changed asynchronously
      * for slab pages, READ_ONCE() should be used here.
      */
     unsigned long memcg_data = READ_ONCE(page->memcg_data);
 
     if (memcg_data & MEMCG_DATA_OBJCGS)
         return NULL;
 
     if (memcg_data & MEMCG_DATA_KMEM) {
         struct obj_cgroup *objcg;
 
         objcg = (void *)(memcg_data & ~MEMCG_DATA_FLAGS_MASK);
         return obj_cgroup_memcg(objcg);
     }
 
     return (struct mem_cgroup *)(memcg_data & ~MEMCG_DATA_FLAGS_MASK);
 }
 
 static inline struct mem_cgroup *get_mem_cgroup_from_objcg(struct obj_cgroup *objcg)
 {
     struct mem_cgroup *memcg;
 
     rcu_read_lock();
 retry:
     memcg = obj_cgroup_memcg(objcg);
     if (unlikely(!css_tryget(&memcg->css)))
         goto retry;
     rcu_read_unlock();
 
     return memcg;
 }
 
 #ifdef CONFIG_MEMCG_KMEM
 /*
  * folio_memcg_kmem - Check if the folio has the memcg_kmem flag set.
  * @folio: Pointer to the folio.
  *
  * Checks if the folio has MemcgKmem flag set. The caller must ensure
  * that the folio has an associated memory cgroup. It's not safe to call
  * this function against some types of folios, e.g. slab folios.
  */
 static inline bool folio_memcg_kmem(struct folio *folio)
 {
     VM_BUG_ON_PGFLAGS(PageTail(&folio->page), &folio->page);
     VM_BUG_ON_FOLIO(folio->memcg_data & MEMCG_DATA_OBJCGS, folio);
     return folio->memcg_data & MEMCG_DATA_KMEM;
 }
 
 
 #else
 static inline bool folio_memcg_kmem(struct folio *folio)
 {
     return false;
 }
 
 #endif
 
 static inline bool PageMemcgKmem(struct page *page)
 {
     return folio_memcg_kmem(page_folio(page));
 }
 
 static inline bool mem_cgroup_is_root(struct mem_cgroup *memcg)
 {
     return (memcg == root_mem_cgroup);
 }
 
 static inline bool mem_cgroup_disabled(void)
 {
     return !cgroup_subsys_enabled(memory_cgrp_subsys);
 }
 
 static inline void mem_cgroup_protection(struct mem_cgroup *root,
                      struct mem_cgroup *memcg,
                      unsigned long *min,
                      unsigned long *low)
 {
     *min = *low = 0;
 
     if (mem_cgroup_disabled())
         return;
 
     /*
      * There is no reclaim protection applied to a targeted reclaim.
      * We are special casing this specific case here because
      * mem_cgroup_protected calculation is not robust enough to keep
      * the protection invariant for calculated effective values for
      * parallel reclaimers with different reclaim target. This is
      * especially a problem for tail memcgs (as they have pages on LRU)
      * which would want to have effective values 0 for targeted reclaim
      * but a different value for external reclaim.
      *
      * Example
      * Let's have global and A's reclaim in parallel:
      *  |
      *  A (low=2G, usage = 3G, max = 3G, children_low_usage = 1.5G)
      *  |\
      *  | C (low = 1G, usage = 2.5G)
      *  B (low = 1G, usage = 0.5G)
      *
      * For the global reclaim
      * A.elow = A.low
      * B.elow = min(B.usage, B.low) because children_low_usage <= A.elow
      * C.elow = min(C.usage, C.low)
      *
      * With the effective values resetting we have A reclaim
      * A.elow = 0
      * B.elow = B.low
      * C.elow = C.low
      *
      * If the global reclaim races with A's reclaim then
      * B.elow = C.elow = 0 because children_low_usage > A.elow)
      * is possible and reclaiming B would be violating the protection.
      *
      */
     if (root == memcg)
         return;
 
     *min = READ_ONCE(memcg->memory.emin);
     *low = READ_ONCE(memcg->memory.elow);
 }
 
 void mem_cgroup_calculate_protection(struct mem_cgroup *root,
                      struct mem_cgroup *memcg);
 
 static inline bool mem_cgroup_supports_protection(struct mem_cgroup *memcg)
 {
     /*
      * The root memcg doesn't account charges, and doesn't support
      * protection.
      */
     return !mem_cgroup_disabled() && !mem_cgroup_is_root(memcg);
 
 }
 
 static inline bool mem_cgroup_below_low(struct mem_cgroup *memcg)
 {
     if (!mem_cgroup_supports_protection(memcg))
         return false;
 
     return READ_ONCE(memcg->memory.elow) >=
         page_counter_read(&memcg->memory);
 }
 
 static inline bool mem_cgroup_below_min(struct mem_cgroup *memcg)
 {
     if (!mem_cgroup_supports_protection(memcg))
         return false;
 
     return READ_ONCE(memcg->memory.emin) >=
         page_counter_read(&memcg->memory);
 }
 
 int __mem_cgroup_charge(struct folio *folio, struct mm_struct *mm, gfp_t gfp);
 
 /**
  * mem_cgroup_charge - Charge a newly allocated folio to a cgroup.
  * @folio: Folio to charge.
  * @mm: mm context of the allocating task.
  * @gfp: Reclaim mode.
  *
  * Try to charge @folio to the memcg that @mm belongs to, reclaiming
  * pages according to @gfp if necessary.  If @mm is NULL, try to
  * charge to the active memcg.
  *
  * Do not use this for folios allocated for swapin.
  *
  * Return: 0 on success. Otherwise, an error code is returned.
  */
 static inline int mem_cgroup_charge(struct folio *folio, struct mm_struct *mm,
                     gfp_t gfp)
 {
     if (mem_cgroup_disabled())
         return 0;
     return __mem_cgroup_charge(folio, mm, gfp);
 }
 
 int mem_cgroup_swapin_charge_page(struct page *page, struct mm_struct *mm,
                   gfp_t gfp, swp_entry_t entry);
 void mem_cgroup_swapin_uncharge_swap(swp_entry_t entry);
 
 void __mem_cgroup_uncharge(struct folio *folio);
 
 /**
  * mem_cgroup_uncharge - Uncharge a folio.
  * @folio: Folio to uncharge.
  *
  * Uncharge a folio previously charged with mem_cgroup_charge().
  */
 static inline void mem_cgroup_uncharge(struct folio *folio)
 {
     if (mem_cgroup_disabled())
         return;
     __mem_cgroup_uncharge(folio);
 }
 
 void __mem_cgroup_uncharge_list(struct list_head *page_list);
 static inline void mem_cgroup_uncharge_list(struct list_head *page_list)
 {
     if (mem_cgroup_disabled())
         return;
     __mem_cgroup_uncharge_list(page_list);
 }
 
 void mem_cgroup_migrate(struct folio *old, struct folio *new);
 
 /**
  * mem_cgroup_lruvec - get the lru list vector for a memcg & node
  * @memcg: memcg of the wanted lruvec
  * @pgdat: pglist_data
  *
  * Returns the lru list vector holding pages for a given @memcg &
  * @pgdat combination. This can be the node lruvec, if the memory
  * controller is disabled.
  */
 static inline struct lruvec *mem_cgroup_lruvec(struct mem_cgroup *memcg,
                            struct pglist_data *pgdat)
 {
     struct mem_cgroup_per_node *mz;
     struct lruvec *lruvec;
 
     if (mem_cgroup_disabled()) {
         lruvec = &pgdat->__lruvec;
         goto out;
     }
 
     if (!memcg)
         memcg = root_mem_cgroup;
 
     mz = memcg->nodeinfo[pgdat->node_id];
     lruvec = &mz->lruvec;
 out:
     /*
      * Since a node can be onlined after the mem_cgroup was created,
      * we have to be prepared to initialize lruvec->pgdat here;
      * and if offlined then reonlined, we need to reinitialize it.
      */
     if (unlikely(lruvec->pgdat != pgdat))
         lruvec->pgdat = pgdat;
     return lruvec;
 }
 
 /**
  * folio_lruvec - return lruvec for isolating/putting an LRU folio
  * @folio: Pointer to the folio.
  *
  * This function relies on folio->mem_cgroup being stable.
  */
 static inline struct lruvec *folio_lruvec(struct folio *folio)
 {
     struct mem_cgroup *memcg = folio_memcg(folio);
 
     VM_WARN_ON_ONCE_FOLIO(!memcg && !mem_cgroup_disabled(), folio);
     return mem_cgroup_lruvec(memcg, folio_pgdat(folio));
 }
 
 struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p);
 
 struct mem_cgroup *get_mem_cgroup_from_mm(struct mm_struct *mm);
 
 struct lruvec *folio_lruvec_lock(struct folio *folio);
 struct lruvec *folio_lruvec_lock_irq(struct folio *folio);
 struct lruvec *folio_lruvec_lock_irqsave(struct folio *folio,
                         unsigned long *flags);
 
 #ifdef CONFIG_DEBUG_VM
 void lruvec_memcg_debug(struct lruvec *lruvec, struct folio *folio);
 #else
 static inline
 void lruvec_memcg_debug(struct lruvec *lruvec, struct folio *folio)
 {
 }
 #endif
 
 static inline
 struct mem_cgroup *mem_cgroup_from_css(struct cgroup_subsys_state *css){
     return css ? container_of(css, struct mem_cgroup, css) : NULL;
 }
 
 static inline bool obj_cgroup_tryget(struct obj_cgroup *objcg)
 {
     return percpu_ref_tryget(&objcg->refcnt);
 }
 
 static inline void obj_cgroup_get(struct obj_cgroup *objcg)
 {
     percpu_ref_get(&objcg->refcnt);
 }
 
 static inline void obj_cgroup_get_many(struct obj_cgroup *objcg,
                        unsigned long nr)
 {
     percpu_ref_get_many(&objcg->refcnt, nr);
 }
 
 static inline void obj_cgroup_put(struct obj_cgroup *objcg)
 {
     percpu_ref_put(&objcg->refcnt);
 }
 
 static inline void mem_cgroup_put(struct mem_cgroup *memcg)
 {
     if (memcg)
         css_put(&memcg->css);
 }
 
 #define mem_cgroup_from_counter(counter, member)    \
     container_of(counter, struct mem_cgroup, member)
 
 struct mem_cgroup *mem_cgroup_iter(struct mem_cgroup *,
                    struct mem_cgroup *,
                    struct mem_cgroup_reclaim_cookie *);
 void mem_cgroup_iter_break(struct mem_cgroup *, struct mem_cgroup *);
 int mem_cgroup_scan_tasks(struct mem_cgroup *,
               int (*)(struct task_struct *, void *), void *);
 
 static inline unsigned short mem_cgroup_id(struct mem_cgroup *memcg)
 {
     if (mem_cgroup_disabled())
         return 0;
 
     return memcg->id.id;
 }
 struct mem_cgroup *mem_cgroup_from_id(unsigned short id);
 
 #ifdef CONFIG_SHRINKER_DEBUG
 static inline unsigned long mem_cgroup_ino(struct mem_cgroup *memcg)
 {
     return memcg ? cgroup_ino(memcg->css.cgroup) : 0;
 }
 
 struct mem_cgroup *mem_cgroup_get_from_ino(unsigned long ino);
 #endif
 
 static inline struct mem_cgroup *mem_cgroup_from_seq(struct seq_file *m)
 {
     return mem_cgroup_from_css(seq_css(m));
 }
 
 static inline struct mem_cgroup *lruvec_memcg(struct lruvec *lruvec)
 {
     struct mem_cgroup_per_node *mz;
 
     if (mem_cgroup_disabled())
         return NULL;
 
     mz = container_of(lruvec, struct mem_cgroup_per_node, lruvec);
     return mz->memcg;
 }
 
 /**
  * parent_mem_cgroup - find the accounting parent of a memcg
  * @memcg: memcg whose parent to find
  *
  * Returns the parent memcg, or NULL if this is the root or the memory
  * controller is in legacy no-hierarchy mode.
  */
 static inline struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *memcg)
 {
     return mem_cgroup_from_css(memcg->css.parent);
 }
 
 static inline bool mem_cgroup_is_descendant(struct mem_cgroup *memcg,
                   struct mem_cgroup *root)
 {
     if (root == memcg)
         return true;
     return cgroup_is_descendant(memcg->css.cgroup, root->css.cgroup);
 }
 
 static inline bool mm_match_cgroup(struct mm_struct *mm,
                    struct mem_cgroup *memcg)
 {
     struct mem_cgroup *task_memcg;
     bool match = false;
 
     rcu_read_lock();
     task_memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
     if (task_memcg)
         match = mem_cgroup_is_descendant(task_memcg, memcg);
     rcu_read_unlock();
     return match;
 }
 
 struct cgroup_subsys_state *mem_cgroup_css_from_page(struct page *page);
 ino_t page_cgroup_ino(struct page *page);
 
 static inline bool mem_cgroup_online(struct mem_cgroup *memcg)
 {
     if (mem_cgroup_disabled())
         return true;
     return !!(memcg->css.flags & CSS_ONLINE);
 }
 
 void mem_cgroup_update_lru_size(struct lruvec *lruvec, enum lru_list lru,
         int zid, int nr_pages);
 
 static inline
 unsigned long mem_cgroup_get_zone_lru_size(struct lruvec *lruvec,
         enum lru_list lru, int zone_idx)
 {
     struct mem_cgroup_per_node *mz;
 
     mz = container_of(lruvec, struct mem_cgroup_per_node, lruvec);
     return READ_ONCE(mz->lru_zone_size[zone_idx][lru]);
 }
 
 void mem_cgroup_handle_over_high(void);
 
 unsigned long mem_cgroup_get_max(struct mem_cgroup *memcg);
 
 unsigned long mem_cgroup_size(struct mem_cgroup *memcg);
 
 void mem_cgroup_print_oom_context(struct mem_cgroup *memcg,
                 struct task_struct *p);
 
 void mem_cgroup_print_oom_meminfo(struct mem_cgroup *memcg);
 
 static inline void mem_cgroup_enter_user_fault(void)
 {
     WARN_ON(current->in_user_fault);
     current->in_user_fault = 1;
 }
 
 static inline void mem_cgroup_exit_user_fault(void)
 {
     WARN_ON(!current->in_user_fault);
     current->in_user_fault = 0;
 }
 
 static inline bool task_in_memcg_oom(struct task_struct *p)
 {
     return p->memcg_in_oom;
 }
 
 bool mem_cgroup_oom_synchronize(bool wait);
 struct mem_cgroup *mem_cgroup_get_oom_group(struct task_struct *victim,
                         struct mem_cgroup *oom_domain);
 void mem_cgroup_print_oom_group(struct mem_cgroup *memcg);
 
 void folio_memcg_lock(struct folio *folio);
 void folio_memcg_unlock(struct folio *folio);
 void lock_page_memcg(struct page *page);
 void unlock_page_memcg(struct page *page);
 
 void __mod_memcg_state(struct mem_cgroup *memcg, int idx, int val);
 
 /* idx can be of type enum memcg_stat_item or node_stat_item */
 static inline void mod_memcg_state(struct mem_cgroup *memcg,
                    int idx, int val)
 {
     unsigned long flags;
 
     local_irq_save(flags);
     __mod_memcg_state(memcg, idx, val);
     local_irq_restore(flags);
 }
 
 static inline void mod_memcg_page_state(struct page *page,
                     int idx, int val)
 {
     struct mem_cgroup *memcg;
 
     if (mem_cgroup_disabled())
         return;
 
     rcu_read_lock();
     memcg = page_memcg(page);
     if (memcg)
         mod_memcg_state(memcg, idx, val);
     rcu_read_unlock();
 }
 
 static inline unsigned long memcg_page_state(struct mem_cgroup *memcg, int idx)
 {
     long x = READ_ONCE(memcg->vmstats.state[idx]);
 #ifdef CONFIG_SMP
     if (x < 0)
         x = 0;
 #endif
     return x;
 }
 
 static inline unsigned long lruvec_page_state(struct lruvec *lruvec,
                           enum node_stat_item idx)
 {
     struct mem_cgroup_per_node *pn;
     long x;
 
     if (mem_cgroup_disabled())
         return node_page_state(lruvec_pgdat(lruvec), idx);
 
     pn = container_of(lruvec, struct mem_cgroup_per_node, lruvec);
     x = READ_ONCE(pn->lruvec_stats.state[idx]);
 #ifdef CONFIG_SMP
     if (x < 0)
         x = 0;
 #endif
     return x;
 }
 
 static inline unsigned long lruvec_page_state_local(struct lruvec *lruvec,
                             enum node_stat_item idx)
 {
     struct mem_cgroup_per_node *pn;
     long x = 0;
     int cpu;
 
     if (mem_cgroup_disabled())
         return node_page_state(lruvec_pgdat(lruvec), idx);
 
     pn = container_of(lruvec, struct mem_cgroup_per_node, lruvec);
     for_each_possible_cpu(cpu)
         x += per_cpu(pn->lruvec_stats_percpu->state[idx], cpu);
 #ifdef CONFIG_SMP
     if (x < 0)
         x = 0;
 #endif
     return x;
 }
 
 void mem_cgroup_flush_stats(void);
 void mem_cgroup_flush_stats_delayed(void);
 
 void __mod_memcg_lruvec_state(struct lruvec *lruvec, enum node_stat_item idx,
                   int val);
 void __mod_lruvec_kmem_state(void *p, enum node_stat_item idx, int val);
 
 static inline void mod_lruvec_kmem_state(void *p, enum node_stat_item idx,
                      int val)
 {
     unsigned long flags;
 
     local_irq_save(flags);
     __mod_lruvec_kmem_state(p, idx, val);
     local_irq_restore(flags);
 }
 
 static inline void mod_memcg_lruvec_state(struct lruvec *lruvec,
                       enum node_stat_item idx, int val)
 {
     unsigned long flags;
 
     local_irq_save(flags);
     __mod_memcg_lruvec_state(lruvec, idx, val);
     local_irq_restore(flags);
 }
 
 void __count_memcg_events(struct mem_cgroup *memcg, enum vm_event_item idx,
               unsigned long count);
 
 static inline void count_memcg_events(struct mem_cgroup *memcg,
                       enum vm_event_item idx,
                       unsigned long count)
 {
     unsigned long flags;
 
     local_irq_save(flags);
     __count_memcg_events(memcg, idx, count);
     local_irq_restore(flags);
 }
 
 static inline void count_memcg_page_event(struct page *page,
                       enum vm_event_item idx)
 {
     struct mem_cgroup *memcg = page_memcg(page);
 
     if (memcg)
         count_memcg_events(memcg, idx, 1);
 }
 
 static inline void count_memcg_folio_events(struct folio *folio,
         enum vm_event_item idx, unsigned long nr)
 {
     struct mem_cgroup *memcg = folio_memcg(folio);
 
     if (memcg)
         count_memcg_events(memcg, idx, nr);
 }
 
 static inline void count_memcg_event_mm(struct mm_struct *mm,
                     enum vm_event_item idx)
 {
     struct mem_cgroup *memcg;
 
     if (mem_cgroup_disabled())
         return;
 
     rcu_read_lock();
     memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
     if (likely(memcg))
         count_memcg_events(memcg, idx, 1);
     rcu_read_unlock();
 }
 
 static inline void memcg_memory_event(struct mem_cgroup *memcg,
                       enum memcg_memory_event event)
 {
     bool swap_event = event == MEMCG_SWAP_HIGH || event == MEMCG_SWAP_MAX ||
               event == MEMCG_SWAP_FAIL;
 
     atomic_long_inc(&memcg->memory_events_local[event]);
     if (!swap_event)
         cgroup_file_notify(&memcg->events_local_file);
 
     do {
         atomic_long_inc(&memcg->memory_events[event]);
         if (swap_event)
             cgroup_file_notify(&memcg->swap_events_file);
         else
             cgroup_file_notify(&memcg->events_file);
 
         if (!cgroup_subsys_on_dfl(memory_cgrp_subsys))
             break;
         if (cgrp_dfl_root.flags & CGRP_ROOT_MEMORY_LOCAL_EVENTS)
             break;
     } while ((memcg = parent_mem_cgroup(memcg)) &&
          !mem_cgroup_is_root(memcg));
 }
 
 static inline void memcg_memory_event_mm(struct mm_struct *mm,
                      enum memcg_memory_event event)
 {
     struct mem_cgroup *memcg;
 
     if (mem_cgroup_disabled())
         return;
 
     rcu_read_lock();
     memcg = mem_cgroup_from_task(rcu_dereference(mm->owner));
     if (likely(memcg))
         memcg_memory_event(memcg, event);
     rcu_read_unlock();
 }
 
 void split_page_memcg(struct page *head, unsigned int nr);
 
 unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order,
                         gfp_t gfp_mask,
                         unsigned long *total_scanned);
 
 #else /* CONFIG_MEMCG */
 
 #define MEM_CGROUP_ID_SHIFT 0
 #define MEM_CGROUP_ID_MAX   0
 
 static inline struct mem_cgroup *folio_memcg(struct folio *folio)
 {
     return NULL;
 }
 
 static inline struct mem_cgroup *page_memcg(struct page *page)
 {
     return NULL;
 }
 
 static inline struct mem_cgroup *folio_memcg_rcu(struct folio *folio)
 {
     WARN_ON_ONCE(!rcu_read_lock_held());
     return NULL;
 }
 
 static inline struct mem_cgroup *page_memcg_check(struct page *page)
 {
     return NULL;
 }
 
 static inline bool folio_memcg_kmem(struct folio *folio)
 {
     return false;
 }
 
 static inline bool PageMemcgKmem(struct page *page)
 {
     return false;
 }
 
 static inline bool mem_cgroup_is_root(struct mem_cgroup *memcg)
 {
     return true;
 }
 
 static inline bool mem_cgroup_disabled(void)
 {
     return true;
 }
 
 static inline void memcg_memory_event(struct mem_cgroup *memcg,
                       enum memcg_memory_event event)
 {
 }
 
 static inline void memcg_memory_event_mm(struct mm_struct *mm,
                      enum memcg_memory_event event)
 {
 }
 
 static inline void mem_cgroup_protection(struct mem_cgroup *root,
                      struct mem_cgroup *memcg,
                      unsigned long *min,
                      unsigned long *low)
 {
     *min = *low = 0;
 }
 
 static inline void mem_cgroup_calculate_protection(struct mem_cgroup *root,
                            struct mem_cgroup *memcg)
 {
 }
 
 static inline bool mem_cgroup_below_low(struct mem_cgroup *memcg)
 {
     return false;
 }
 
 static inline bool mem_cgroup_below_min(struct mem_cgroup *memcg)
 {
     return false;
 }
 
 static inline int mem_cgroup_charge(struct folio *folio,
         struct mm_struct *mm, gfp_t gfp)
 {
     return 0;
 }
 
 static inline int mem_cgroup_swapin_charge_page(struct page *page,
             struct mm_struct *mm, gfp_t gfp, swp_entry_t entry)
 {
     return 0;
 }
 
 static inline void mem_cgroup_swapin_uncharge_swap(swp_entry_t entry)
 {
 }
 
 static inline void mem_cgroup_uncharge(struct folio *folio)
 {
 }
 
 static inline void mem_cgroup_uncharge_list(struct list_head *page_list)
 {
 }
 
 static inline void mem_cgroup_migrate(struct folio *old, struct folio *new)
 {
 }
 
 static inline struct lruvec *mem_cgroup_lruvec(struct mem_cgroup *memcg,
                            struct pglist_data *pgdat)
 {
     return &pgdat->__lruvec;
 }
 
 static inline struct lruvec *folio_lruvec(struct folio *folio)
 {
     struct pglist_data *pgdat = folio_pgdat(folio);
     return &pgdat->__lruvec;
 }
 
 static inline
 void lruvec_memcg_debug(struct lruvec *lruvec, struct folio *folio)
 {
 }
 
 static inline struct mem_cgroup *parent_mem_cgroup(struct mem_cgroup *memcg)
 {
     return NULL;
 }
 
 static inline bool mm_match_cgroup(struct mm_struct *mm,
         struct mem_cgroup *memcg)
 {
     return true;
 }
 
 static inline struct mem_cgroup *get_mem_cgroup_from_mm(struct mm_struct *mm)
 {
     return NULL;
 }
 
 static inline
 struct mem_cgroup *mem_cgroup_from_css(struct cgroup_subsys_state *css)
 {
     return NULL;
 }
 
 static inline void obj_cgroup_put(struct obj_cgroup *objcg)
 {
 }
 
 static inline void mem_cgroup_put(struct mem_cgroup *memcg)
 {
 }
 
 static inline struct lruvec *folio_lruvec_lock(struct folio *folio)
 {
     struct pglist_data *pgdat = folio_pgdat(folio);
 
     spin_lock(&pgdat->__lruvec.lru_lock);
     return &pgdat->__lruvec;
 }
 
 static inline struct lruvec *folio_lruvec_lock_irq(struct folio *folio)
 {
     struct pglist_data *pgdat = folio_pgdat(folio);
 
     spin_lock_irq(&pgdat->__lruvec.lru_lock);
     return &pgdat->__lruvec;
 }
 
 static inline struct lruvec *folio_lruvec_lock_irqsave(struct folio *folio,
         unsigned long *flagsp)
 {
     struct pglist_data *pgdat = folio_pgdat(folio);
 
     spin_lock_irqsave(&pgdat->__lruvec.lru_lock, *flagsp);
     return &pgdat->__lruvec;
 }
 
 static inline struct mem_cgroup *
 mem_cgroup_iter(struct mem_cgroup *root,
         struct mem_cgroup *prev,
         struct mem_cgroup_reclaim_cookie *reclaim)
 {
     return NULL;
 }
 
 static inline void mem_cgroup_iter_break(struct mem_cgroup *root,
                      struct mem_cgroup *prev)
 {
 }
 
 static inline int mem_cgroup_scan_tasks(struct mem_cgroup *memcg,
         int (*fn)(struct task_struct *, void *), void *arg)
 {
     return 0;
 }
 
 static inline unsigned short mem_cgroup_id(struct mem_cgroup *memcg)
 {
     return 0;
 }
 
 static inline struct mem_cgroup *mem_cgroup_from_id(unsigned short id)
 {
     WARN_ON_ONCE(id);
     /* XXX: This should always return root_mem_cgroup */
     return NULL;
 }
 
 #ifdef CONFIG_SHRINKER_DEBUG
 static inline unsigned long mem_cgroup_ino(struct mem_cgroup *memcg)
 {
     return 0;
 }
 
 static inline struct mem_cgroup *mem_cgroup_get_from_ino(unsigned long ino)
 {
     return NULL;
 }
 #endif
 
 static inline struct mem_cgroup *mem_cgroup_from_seq(struct seq_file *m)
 {
     return NULL;
 }
 
 static inline struct mem_cgroup *lruvec_memcg(struct lruvec *lruvec)
 {
     return NULL;
 }
 
 static inline bool mem_cgroup_online(struct mem_cgroup *memcg)
 {
     return true;
 }
 
 static inline
 unsigned long mem_cgroup_get_zone_lru_size(struct lruvec *lruvec,
         enum lru_list lru, int zone_idx)
 {
     return 0;
 }
 
 static inline unsigned long mem_cgroup_get_max(struct mem_cgroup *memcg)
 {
     return 0;
 }
 
 static inline unsigned long mem_cgroup_size(struct mem_cgroup *memcg)
 {
     return 0;
 }
 
 static inline void
 mem_cgroup_print_oom_context(struct mem_cgroup *memcg, struct task_struct *p)
 {
 }
 
 static inline void
 mem_cgroup_print_oom_meminfo(struct mem_cgroup *memcg)
 {
 }
 
 static inline void lock_page_memcg(struct page *page)
 {
 }
 
 static inline void unlock_page_memcg(struct page *page)
 {
 }
 
 static inline void folio_memcg_lock(struct folio *folio)
 {
 }
 
 static inline void folio_memcg_unlock(struct folio *folio)
 {
 }
 
 static inline void mem_cgroup_handle_over_high(void)
 {
 }
 
 static inline void mem_cgroup_enter_user_fault(void)
 {
 }
 
 static inline void mem_cgroup_exit_user_fault(void)
 {
 }
 
 static inline bool task_in_memcg_oom(struct task_struct *p)
 {
     return false;
 }
 
 static inline bool mem_cgroup_oom_synchronize(bool wait)
 {
     return false;
 }
 
 static inline struct mem_cgroup *mem_cgroup_get_oom_group(
     struct task_struct *victim, struct mem_cgroup *oom_domain)
 {
     return NULL;
 }
 
 static inline void mem_cgroup_print_oom_group(struct mem_cgroup *memcg)
 {
 }
 
 static inline void __mod_memcg_state(struct mem_cgroup *memcg,
                      int idx,
                      int nr)
 {
 }
 
 static inline void mod_memcg_state(struct mem_cgroup *memcg,
                    int idx,
                    int nr)
 {
 }
 
 static inline void mod_memcg_page_state(struct page *page,
                     int idx, int val)
 {
 }
 
 static inline unsigned long memcg_page_state(struct mem_cgroup *memcg, int idx)
 {
     return 0;
 }
 
 static inline unsigned long lruvec_page_state(struct lruvec *lruvec,
                           enum node_stat_item idx)
 {
     return node_page_state(lruvec_pgdat(lruvec), idx);
 }
 
 static inline unsigned long lruvec_page_state_local(struct lruvec *lruvec,
                             enum node_stat_item idx)
 {
     return node_page_state(lruvec_pgdat(lruvec), idx);
 }
 
 static inline void mem_cgroup_flush_stats(void)
 {
 }
 
 static inline void mem_cgroup_flush_stats_delayed(void)
 {
 }
 
 static inline void __mod_memcg_lruvec_state(struct lruvec *lruvec,
                         enum node_stat_item idx, int val)
 {
 }
 
 static inline void __mod_lruvec_kmem_state(void *p, enum node_stat_item idx,
                        int val)
 {
     struct page *page = virt_to_head_page(p);
 
     __mod_node_page_state(page_pgdat(page), idx, val);
 }
 
 static inline void mod_lruvec_kmem_state(void *p, enum node_stat_item idx,
                      int val)
 {
     struct page *page = virt_to_head_page(p);
 
     mod_node_page_state(page_pgdat(page), idx, val);
 }
 
 static inline void count_memcg_events(struct mem_cgroup *memcg,
                       enum vm_event_item idx,
                       unsigned long count)
 {
 }
 
 static inline void __count_memcg_events(struct mem_cgroup *memcg,
                     enum vm_event_item idx,
                     unsigned long count)
 {
 }
 
 static inline void count_memcg_page_event(struct page *page,
                       int idx)
 {
 }
 
 static inline void count_memcg_folio_events(struct folio *folio,
         enum vm_event_item idx, unsigned long nr)
 {
 }
 
 static inline
 void count_memcg_event_mm(struct mm_struct *mm, enum vm_event_item idx)
 {
 }
 
 static inline void split_page_memcg(struct page *head, unsigned int nr)
 {
 }
 
 static inline
 unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order,
                         gfp_t gfp_mask,
                         unsigned long *total_scanned)
 {
     return 0;
 }
 #endif /* CONFIG_MEMCG */
 
 static inline void __inc_lruvec_kmem_state(void *p, enum node_stat_item idx)
 {
     __mod_lruvec_kmem_state(p, idx, 1);
 }
 
 static inline void __dec_lruvec_kmem_state(void *p, enum node_stat_item idx)
 {
     __mod_lruvec_kmem_state(p, idx, -1);
 }
 
 static inline struct lruvec *parent_lruvec(struct lruvec *lruvec)
 {
     struct mem_cgroup *memcg;
 
     memcg = lruvec_memcg(lruvec);
     if (!memcg)
         return NULL;
     memcg = parent_mem_cgroup(memcg);
     if (!memcg)
         return NULL;
     return mem_cgroup_lruvec(memcg, lruvec_pgdat(lruvec));
 }
 
 static inline void unlock_page_lruvec(struct lruvec *lruvec)
 {
     spin_unlock(&lruvec->lru_lock);
 }
 
 static inline void unlock_page_lruvec_irq(struct lruvec *lruvec)
 {
     spin_unlock_irq(&lruvec->lru_lock);
 }
 
 static inline void unlock_page_lruvec_irqrestore(struct lruvec *lruvec,
         unsigned long flags)
 {
     spin_unlock_irqrestore(&lruvec->lru_lock, flags);
 }
 
 /* Test requires a stable page->memcg binding, see page_memcg() */
 static inline bool folio_matches_lruvec(struct folio *folio,
         struct lruvec *lruvec)
 {
     return lruvec_pgdat(lruvec) == folio_pgdat(folio) &&
            lruvec_memcg(lruvec) == folio_memcg(folio);
 }
 
 /* Don't lock again iff page's lruvec locked */
 static inline struct lruvec *folio_lruvec_relock_irq(struct folio *folio,
         struct lruvec *locked_lruvec)
 {
     if (locked_lruvec) {
         if (folio_matches_lruvec(folio, locked_lruvec))
             return locked_lruvec;
 
         unlock_page_lruvec_irq(locked_lruvec);
     }
 
     return folio_lruvec_lock_irq(folio);
 }
 
 /* Don't lock again iff page's lruvec locked */
 static inline struct lruvec *folio_lruvec_relock_irqsave(struct folio *folio,
         struct lruvec *locked_lruvec, unsigned long *flags)
 {
     if (locked_lruvec) {
         if (folio_matches_lruvec(folio, locked_lruvec))
             return locked_lruvec;
 
         unlock_page_lruvec_irqrestore(locked_lruvec, *flags);
     }
 
     return folio_lruvec_lock_irqsave(folio, flags);
 }
 
 #ifdef CONFIG_CGROUP_WRITEBACK
 
 struct wb_domain *mem_cgroup_wb_domain(struct bdi_writeback *wb);
 void mem_cgroup_wb_stats(struct bdi_writeback *wb, unsigned long *pfilepages,
              unsigned long *pheadroom, unsigned long *pdirty,
              unsigned long *pwriteback);
 
 void mem_cgroup_track_foreign_dirty_slowpath(struct folio *folio,
                          struct bdi_writeback *wb);
 
 static inline void mem_cgroup_track_foreign_dirty(struct folio *folio,
                           struct bdi_writeback *wb)
 {
     if (mem_cgroup_disabled())
         return;
 
     if (unlikely(&folio_memcg(folio)->css != wb->memcg_css))
         mem_cgroup_track_foreign_dirty_slowpath(folio, wb);
 }
 
 void mem_cgroup_flush_foreign(struct bdi_writeback *wb);
 
 #else   /* CONFIG_CGROUP_WRITEBACK */
 
 static inline struct wb_domain *mem_cgroup_wb_domain(struct bdi_writeback *wb)
 {
     return NULL;
 }
 
 static inline void mem_cgroup_wb_stats(struct bdi_writeback *wb,
                        unsigned long *pfilepages,
                        unsigned long *pheadroom,
                        unsigned long *pdirty,
                        unsigned long *pwriteback)
 {
 }
 
 static inline void mem_cgroup_track_foreign_dirty(struct folio *folio,
                           struct bdi_writeback *wb)
 {
 }
 
 static inline void mem_cgroup_flush_foreign(struct bdi_writeback *wb)
 {
 }
 
 #endif  /* CONFIG_CGROUP_WRITEBACK */
 
 struct sock;
 bool mem_cgroup_charge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages,
                  gfp_t gfp_mask);
 void mem_cgroup_uncharge_skmem(struct mem_cgroup *memcg, unsigned int nr_pages);
 #ifdef CONFIG_MEMCG
 extern struct static_key_false memcg_sockets_enabled_key;
 #define mem_cgroup_sockets_enabled static_branch_unlikely(&memcg_sockets_enabled_key)
 void mem_cgroup_sk_alloc(struct sock *sk);
 void mem_cgroup_sk_free(struct sock *sk);
 static inline bool mem_cgroup_under_socket_pressure(struct mem_cgroup *memcg)
 {
     if (!cgroup_subsys_on_dfl(memory_cgrp_subsys) && memcg->tcpmem_pressure)
         return true;
     do {
         if (time_before(jiffies, READ_ONCE(memcg->socket_pressure)))
             return true;
     } while ((memcg = parent_mem_cgroup(memcg)));
     return false;
 }
 
 int alloc_shrinker_info(struct mem_cgroup *memcg);
 void free_shrinker_info(struct mem_cgroup *memcg);
 void set_shrinker_bit(struct mem_cgroup *memcg, int nid, int shrinker_id);
 void reparent_shrinker_deferred(struct mem_cgroup *memcg);
 #else
 #define mem_cgroup_sockets_enabled 0
 static inline void mem_cgroup_sk_alloc(struct sock *sk) { };
 static inline void mem_cgroup_sk_free(struct sock *sk) { };
 static inline bool mem_cgroup_under_socket_pressure(struct mem_cgroup *memcg)
 {
     return false;
 }
 
 static inline void set_shrinker_bit(struct mem_cgroup *memcg,
                     int nid, int shrinker_id)
 {
 }
 #endif
 
 #ifdef CONFIG_MEMCG_KMEM
 bool mem_cgroup_kmem_disabled(void);
 int __memcg_kmem_charge_page(struct page *page, gfp_t gfp, int order);
 void __memcg_kmem_uncharge_page(struct page *page, int order);
 
 struct obj_cgroup *get_obj_cgroup_from_current(void);
 struct obj_cgroup *get_obj_cgroup_from_page(struct page *page);
 
 int obj_cgroup_charge(struct obj_cgroup *objcg, gfp_t gfp, size_t size);
 void obj_cgroup_uncharge(struct obj_cgroup *objcg, size_t size);
 
 extern struct static_key_false memcg_kmem_enabled_key;
 
 static inline bool memcg_kmem_enabled(void)
 {
     return static_branch_likely(&memcg_kmem_enabled_key);
 }
 
 static inline int memcg_kmem_charge_page(struct page *page, gfp_t gfp,
                      int order)
 {
     if (memcg_kmem_enabled())
         return __memcg_kmem_charge_page(page, gfp, order);
     return 0;
 }
 
 static inline void memcg_kmem_uncharge_page(struct page *page, int order)
 {
     if (memcg_kmem_enabled())
         __memcg_kmem_uncharge_page(page, order);
 }
 
 /*
  * A helper for accessing memcg's kmem_id, used for getting
  * corresponding LRU lists.
  */
 static inline int memcg_kmem_id(struct mem_cgroup *memcg)
 {
     return memcg ? memcg->kmemcg_id : -1;
 }
 
 struct mem_cgroup *mem_cgroup_from_obj(void *p);
 struct mem_cgroup *mem_cgroup_from_slab_obj(void *p);
 
 static inline void count_objcg_event(struct obj_cgroup *objcg,
                      enum vm_event_item idx)
 {
     struct mem_cgroup *memcg;
 
     if (mem_cgroup_kmem_disabled())
         return;
 
     rcu_read_lock();
     memcg = obj_cgroup_memcg(objcg);
     count_memcg_events(memcg, idx, 1);
     rcu_read_unlock();
 }
 
 #else
 static inline bool mem_cgroup_kmem_disabled(void)
 {
     return true;
 }
 
 static inline int memcg_kmem_charge_page(struct page *page, gfp_t gfp,
                      int order)
 {
     return 0;
 }
 
 static inline void memcg_kmem_uncharge_page(struct page *page, int order)
 {
 }
 
 static inline int __memcg_kmem_charge_page(struct page *page, gfp_t gfp,
                        int order)
 {
     return 0;
 }
 
 static inline void __memcg_kmem_uncharge_page(struct page *page, int order)
 {
 }
 
 static inline struct obj_cgroup *get_obj_cgroup_from_page(struct page *page)
 {
     return NULL;
 }
 
 static inline bool memcg_kmem_enabled(void)
 {
     return false;
 }
 
 static inline int memcg_kmem_id(struct mem_cgroup *memcg)
 {
     return -1;
 }
 
 static inline struct mem_cgroup *mem_cgroup_from_obj(void *p)
 {
     return NULL;
 }
 
 static inline struct mem_cgroup *mem_cgroup_from_slab_obj(void *p)
 {
     return NULL;
 }
 
 static inline void count_objcg_event(struct obj_cgroup *objcg,
                      enum vm_event_item idx)
 {
 }
 
 #endif /* CONFIG_MEMCG_KMEM */
 
 #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP)
 bool obj_cgroup_may_zswap(struct obj_cgroup *objcg);
 void obj_cgroup_charge_zswap(struct obj_cgroup *objcg, size_t size);
 void obj_cgroup_uncharge_zswap(struct obj_cgroup *objcg, size_t size);
 #else
 static inline bool obj_cgroup_may_zswap(struct obj_cgroup *objcg)
 {
     return true;
 }
 static inline void obj_cgroup_charge_zswap(struct obj_cgroup *objcg,
                        size_t size)
 {
 }
 static inline void obj_cgroup_uncharge_zswap(struct obj_cgroup *objcg,
                          size_t size)
 {
 }
 #endif
 
 #endif /* _LINUX_MEMCONTROL_H */

This page was automatically generated by the 2.1.0 LXR engine. The LXR team