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1/* SPDX-License-Identifier: GPL-2.0 */2#ifndef _LINUX_MMZONE_H3#define _LINUX_MMZONE_H4 5#ifndef __ASSEMBLY__6#ifndef __GENERATING_BOUNDS_H7 8#include <linux/spinlock.h>9#include <linux/list.h>10#include <linux/list_nulls.h>11#include <linux/wait.h>12#include <linux/bitops.h>13#include <linux/cache.h>14#include <linux/threads.h>15#include <linux/numa.h>16#include <linux/init.h>17#include <linux/seqlock.h>18#include <linux/nodemask.h>19#include <linux/pageblock-flags.h>20#include <linux/page-flags-layout.h>21#include <linux/atomic.h>22#include <linux/mm_types.h>23#include <linux/page-flags.h>24#include <linux/local_lock.h>25#include <linux/zswap.h>26#include <asm/page.h>27 28/* Free memory management - zoned buddy allocator. */29#ifndef CONFIG_ARCH_FORCE_MAX_ORDER30#define MAX_PAGE_ORDER 1031#else32#define MAX_PAGE_ORDER CONFIG_ARCH_FORCE_MAX_ORDER33#endif34#define MAX_ORDER_NR_PAGES (1 << MAX_PAGE_ORDER)35 36#define IS_MAX_ORDER_ALIGNED(pfn) IS_ALIGNED(pfn, MAX_ORDER_NR_PAGES)37 38#define NR_PAGE_ORDERS (MAX_PAGE_ORDER + 1)39 40/*41 * PAGE_ALLOC_COSTLY_ORDER is the order at which allocations are deemed42 * costly to service. That is between allocation orders which should43 * coalesce naturally under reasonable reclaim pressure and those which44 * will not.45 */46#define PAGE_ALLOC_COSTLY_ORDER 347 48enum migratetype {49 MIGRATE_UNMOVABLE,50 MIGRATE_MOVABLE,51 MIGRATE_RECLAIMABLE,52 MIGRATE_PCPTYPES, /* the number of types on the pcp lists */53 MIGRATE_HIGHATOMIC = MIGRATE_PCPTYPES,54#ifdef CONFIG_CMA55 /*56 * MIGRATE_CMA migration type is designed to mimic the way57 * ZONE_MOVABLE works. Only movable pages can be allocated58 * from MIGRATE_CMA pageblocks and page allocator never59 * implicitly change migration type of MIGRATE_CMA pageblock.60 *61 * The way to use it is to change migratetype of a range of62 * pageblocks to MIGRATE_CMA which can be done by63 * __free_pageblock_cma() function.64 */65 MIGRATE_CMA,66#endif67#ifdef CONFIG_MEMORY_ISOLATION68 MIGRATE_ISOLATE, /* can't allocate from here */69#endif70 MIGRATE_TYPES71};72 73/* In mm/page_alloc.c; keep in sync also with show_migration_types() there */74extern const char * const migratetype_names[MIGRATE_TYPES];75 76#ifdef CONFIG_CMA77# define is_migrate_cma(migratetype) unlikely((migratetype) == MIGRATE_CMA)78# define is_migrate_cma_page(_page) (get_pageblock_migratetype(_page) == MIGRATE_CMA)79# define is_migrate_cma_folio(folio, pfn) (MIGRATE_CMA == \80 get_pfnblock_flags_mask(&folio->page, pfn, MIGRATETYPE_MASK))81#else82# define is_migrate_cma(migratetype) false83# define is_migrate_cma_page(_page) false84# define is_migrate_cma_folio(folio, pfn) false85#endif86 87static inline bool is_migrate_movable(int mt)88{89 return is_migrate_cma(mt) || mt == MIGRATE_MOVABLE;90}91 92/*93 * Check whether a migratetype can be merged with another migratetype.94 *95 * It is only mergeable when it can fall back to other migratetypes for96 * allocation. See fallbacks[MIGRATE_TYPES][3] in page_alloc.c.97 */98static inline bool migratetype_is_mergeable(int mt)99{100 return mt < MIGRATE_PCPTYPES;101}102 103#define for_each_migratetype_order(order, type) \104 for (order = 0; order < NR_PAGE_ORDERS; order++) \105 for (type = 0; type < MIGRATE_TYPES; type++)106 107extern int page_group_by_mobility_disabled;108 109#define MIGRATETYPE_MASK ((1UL << PB_migratetype_bits) - 1)110 111#define get_pageblock_migratetype(page) \112 get_pfnblock_flags_mask(page, page_to_pfn(page), MIGRATETYPE_MASK)113 114#define folio_migratetype(folio) \115 get_pfnblock_flags_mask(&folio->page, folio_pfn(folio), \116 MIGRATETYPE_MASK)117struct free_area {118 struct list_head free_list[MIGRATE_TYPES];119 unsigned long nr_free;120};121 122struct pglist_data;123 124#ifdef CONFIG_NUMA125enum numa_stat_item {126 NUMA_HIT, /* allocated in intended node */127 NUMA_MISS, /* allocated in non intended node */128 NUMA_FOREIGN, /* was intended here, hit elsewhere */129 NUMA_INTERLEAVE_HIT, /* interleaver preferred this zone */130 NUMA_LOCAL, /* allocation from local node */131 NUMA_OTHER, /* allocation from other node */132 NR_VM_NUMA_EVENT_ITEMS133};134#else135#define NR_VM_NUMA_EVENT_ITEMS 0136#endif137 138enum zone_stat_item {139 /* First 128 byte cacheline (assuming 64 bit words) */140 NR_FREE_PAGES,141 NR_ZONE_LRU_BASE, /* Used only for compaction and reclaim retry */142 NR_ZONE_INACTIVE_ANON = NR_ZONE_LRU_BASE,143 NR_ZONE_ACTIVE_ANON,144 NR_ZONE_INACTIVE_FILE,145 NR_ZONE_ACTIVE_FILE,146 NR_ZONE_UNEVICTABLE,147 NR_ZONE_WRITE_PENDING, /* Count of dirty, writeback and unstable pages */148 NR_MLOCK, /* mlock()ed pages found and moved off LRU */149 /* Second 128 byte cacheline */150 NR_BOUNCE,151#if IS_ENABLED(CONFIG_ZSMALLOC)152 NR_ZSPAGES, /* allocated in zsmalloc */153#endif154 NR_FREE_CMA_PAGES,155#ifdef CONFIG_UNACCEPTED_MEMORY156 NR_UNACCEPTED,157#endif158 NR_VM_ZONE_STAT_ITEMS };159 160enum node_stat_item {161 NR_LRU_BASE,162 NR_INACTIVE_ANON = NR_LRU_BASE, /* must match order of LRU_[IN]ACTIVE */163 NR_ACTIVE_ANON, /* " " " " " */164 NR_INACTIVE_FILE, /* " " " " " */165 NR_ACTIVE_FILE, /* " " " " " */166 NR_UNEVICTABLE, /* " " " " " */167 NR_SLAB_RECLAIMABLE_B,168 NR_SLAB_UNRECLAIMABLE_B,169 NR_ISOLATED_ANON, /* Temporary isolated pages from anon lru */170 NR_ISOLATED_FILE, /* Temporary isolated pages from file lru */171 WORKINGSET_NODES,172 WORKINGSET_REFAULT_BASE,173 WORKINGSET_REFAULT_ANON = WORKINGSET_REFAULT_BASE,174 WORKINGSET_REFAULT_FILE,175 WORKINGSET_ACTIVATE_BASE,176 WORKINGSET_ACTIVATE_ANON = WORKINGSET_ACTIVATE_BASE,177 WORKINGSET_ACTIVATE_FILE,178 WORKINGSET_RESTORE_BASE,179 WORKINGSET_RESTORE_ANON = WORKINGSET_RESTORE_BASE,180 WORKINGSET_RESTORE_FILE,181 WORKINGSET_NODERECLAIM,182 NR_ANON_MAPPED, /* Mapped anonymous pages */183 NR_FILE_MAPPED, /* pagecache pages mapped into pagetables.184 only modified from process context */185 NR_FILE_PAGES,186 NR_FILE_DIRTY,187 NR_WRITEBACK,188 NR_WRITEBACK_TEMP, /* Writeback using temporary buffers */189 NR_SHMEM, /* shmem pages (included tmpfs/GEM pages) */190 NR_SHMEM_THPS,191 NR_SHMEM_PMDMAPPED,192 NR_FILE_THPS,193 NR_FILE_PMDMAPPED,194 NR_ANON_THPS,195 NR_VMSCAN_WRITE,196 NR_VMSCAN_IMMEDIATE, /* Prioritise for reclaim when writeback ends */197 NR_DIRTIED, /* page dirtyings since bootup */198 NR_WRITTEN, /* page writings since bootup */199 NR_THROTTLED_WRITTEN, /* NR_WRITTEN while reclaim throttled */200 NR_KERNEL_MISC_RECLAIMABLE, /* reclaimable non-slab kernel pages */201 NR_FOLL_PIN_ACQUIRED, /* via: pin_user_page(), gup flag: FOLL_PIN */202 NR_FOLL_PIN_RELEASED, /* pages returned via unpin_user_page() */203 NR_KERNEL_STACK_KB, /* measured in KiB */204#if IS_ENABLED(CONFIG_SHADOW_CALL_STACK)205 NR_KERNEL_SCS_KB, /* measured in KiB */206#endif207 NR_PAGETABLE, /* used for pagetables */208 NR_SECONDARY_PAGETABLE, /* secondary pagetables, KVM & IOMMU */209#ifdef CONFIG_IOMMU_SUPPORT210 NR_IOMMU_PAGES, /* # of pages allocated by IOMMU */211#endif212#ifdef CONFIG_SWAP213 NR_SWAPCACHE,214#endif215#ifdef CONFIG_NUMA_BALANCING216 PGPROMOTE_SUCCESS, /* promote successfully */217 PGPROMOTE_CANDIDATE, /* candidate pages to promote */218#endif219 /* PGDEMOTE_*: pages demoted */220 PGDEMOTE_KSWAPD,221 PGDEMOTE_DIRECT,222 PGDEMOTE_KHUGEPAGED,223 NR_VM_NODE_STAT_ITEMS224};225 226/*227 * Returns true if the item should be printed in THPs (/proc/vmstat228 * currently prints number of anon, file and shmem THPs. But the item229 * is charged in pages).230 */231static __always_inline bool vmstat_item_print_in_thp(enum node_stat_item item)232{233 if (!IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE))234 return false;235 236 return item == NR_ANON_THPS ||237 item == NR_FILE_THPS ||238 item == NR_SHMEM_THPS ||239 item == NR_SHMEM_PMDMAPPED ||240 item == NR_FILE_PMDMAPPED;241}242 243/*244 * Returns true if the value is measured in bytes (most vmstat values are245 * measured in pages). This defines the API part, the internal representation246 * might be different.247 */248static __always_inline bool vmstat_item_in_bytes(int idx)249{250 /*251 * Global and per-node slab counters track slab pages.252 * It's expected that changes are multiples of PAGE_SIZE.253 * Internally values are stored in pages.254 *255 * Per-memcg and per-lruvec counters track memory, consumed256 * by individual slab objects. These counters are actually257 * byte-precise.258 */259 return (idx == NR_SLAB_RECLAIMABLE_B ||260 idx == NR_SLAB_UNRECLAIMABLE_B);261}262 263/*264 * We do arithmetic on the LRU lists in various places in the code,265 * so it is important to keep the active lists LRU_ACTIVE higher in266 * the array than the corresponding inactive lists, and to keep267 * the *_FILE lists LRU_FILE higher than the corresponding _ANON lists.268 *269 * This has to be kept in sync with the statistics in zone_stat_item270 * above and the descriptions in vmstat_text in mm/vmstat.c271 */272#define LRU_BASE 0273#define LRU_ACTIVE 1274#define LRU_FILE 2275 276enum lru_list {277 LRU_INACTIVE_ANON = LRU_BASE,278 LRU_ACTIVE_ANON = LRU_BASE + LRU_ACTIVE,279 LRU_INACTIVE_FILE = LRU_BASE + LRU_FILE,280 LRU_ACTIVE_FILE = LRU_BASE + LRU_FILE + LRU_ACTIVE,281 LRU_UNEVICTABLE,282 NR_LRU_LISTS283};284 285enum vmscan_throttle_state {286 VMSCAN_THROTTLE_WRITEBACK,287 VMSCAN_THROTTLE_ISOLATED,288 VMSCAN_THROTTLE_NOPROGRESS,289 VMSCAN_THROTTLE_CONGESTED,290 NR_VMSCAN_THROTTLE,291};292 293#define for_each_lru(lru) for (lru = 0; lru < NR_LRU_LISTS; lru++)294 295#define for_each_evictable_lru(lru) for (lru = 0; lru <= LRU_ACTIVE_FILE; lru++)296 297static inline bool is_file_lru(enum lru_list lru)298{299 return (lru == LRU_INACTIVE_FILE || lru == LRU_ACTIVE_FILE);300}301 302static inline bool is_active_lru(enum lru_list lru)303{304 return (lru == LRU_ACTIVE_ANON || lru == LRU_ACTIVE_FILE);305}306 307#define WORKINGSET_ANON 0308#define WORKINGSET_FILE 1309#define ANON_AND_FILE 2310 311enum lruvec_flags {312 /*313 * An lruvec has many dirty pages backed by a congested BDI:314 * 1. LRUVEC_CGROUP_CONGESTED is set by cgroup-level reclaim.315 * It can be cleared by cgroup reclaim or kswapd.316 * 2. LRUVEC_NODE_CONGESTED is set by kswapd node-level reclaim.317 * It can only be cleared by kswapd.318 *319 * Essentially, kswapd can unthrottle an lruvec throttled by cgroup320 * reclaim, but not vice versa. This only applies to the root cgroup.321 * The goal is to prevent cgroup reclaim on the root cgroup (e.g.322 * memory.reclaim) to unthrottle an unbalanced node (that was throttled323 * by kswapd).324 */325 LRUVEC_CGROUP_CONGESTED,326 LRUVEC_NODE_CONGESTED,327};328 329#endif /* !__GENERATING_BOUNDS_H */330 331/*332 * Evictable pages are divided into multiple generations. The youngest and the333 * oldest generation numbers, max_seq and min_seq, are monotonically increasing.334 * They form a sliding window of a variable size [MIN_NR_GENS, MAX_NR_GENS]. An335 * offset within MAX_NR_GENS, i.e., gen, indexes the LRU list of the336 * corresponding generation. The gen counter in folio->flags stores gen+1 while337 * a page is on one of lrugen->folios[]. Otherwise it stores 0.338 *339 * A page is added to the youngest generation on faulting. The aging needs to340 * check the accessed bit at least twice before handing this page over to the341 * eviction. The first check takes care of the accessed bit set on the initial342 * fault; the second check makes sure this page hasn't been used since then.343 * This process, AKA second chance, requires a minimum of two generations,344 * hence MIN_NR_GENS. And to maintain ABI compatibility with the active/inactive345 * LRU, e.g., /proc/vmstat, these two generations are considered active; the346 * rest of generations, if they exist, are considered inactive. See347 * lru_gen_is_active().348 *349 * PG_active is always cleared while a page is on one of lrugen->folios[] so350 * that the aging needs not to worry about it. And it's set again when a page351 * considered active is isolated for non-reclaiming purposes, e.g., migration.352 * See lru_gen_add_folio() and lru_gen_del_folio().353 *354 * MAX_NR_GENS is set to 4 so that the multi-gen LRU can support twice the355 * number of categories of the active/inactive LRU when keeping track of356 * accesses through page tables. This requires order_base_2(MAX_NR_GENS+1) bits357 * in folio->flags.358 */359#define MIN_NR_GENS 2U360#define MAX_NR_GENS 4U361 362/*363 * Each generation is divided into multiple tiers. A page accessed N times364 * through file descriptors is in tier order_base_2(N). A page in the first tier365 * (N=0,1) is marked by PG_referenced unless it was faulted in through page366 * tables or read ahead. A page in any other tier (N>1) is marked by367 * PG_referenced and PG_workingset. This implies a minimum of two tiers is368 * supported without using additional bits in folio->flags.369 *370 * In contrast to moving across generations which requires the LRU lock, moving371 * across tiers only involves atomic operations on folio->flags and therefore372 * has a negligible cost in the buffered access path. In the eviction path,373 * comparisons of refaulted/(evicted+protected) from the first tier and the374 * rest infer whether pages accessed multiple times through file descriptors375 * are statistically hot and thus worth protecting.376 *377 * MAX_NR_TIERS is set to 4 so that the multi-gen LRU can support twice the378 * number of categories of the active/inactive LRU when keeping track of379 * accesses through file descriptors. This uses MAX_NR_TIERS-2 spare bits in380 * folio->flags.381 */382#define MAX_NR_TIERS 4U383 384#ifndef __GENERATING_BOUNDS_H385 386struct lruvec;387struct page_vma_mapped_walk;388 389#define LRU_GEN_MASK ((BIT(LRU_GEN_WIDTH) - 1) << LRU_GEN_PGOFF)390#define LRU_REFS_MASK ((BIT(LRU_REFS_WIDTH) - 1) << LRU_REFS_PGOFF)391 392#ifdef CONFIG_LRU_GEN393 394enum {395 LRU_GEN_ANON,396 LRU_GEN_FILE,397};398 399enum {400 LRU_GEN_CORE,401 LRU_GEN_MM_WALK,402 LRU_GEN_NONLEAF_YOUNG,403 NR_LRU_GEN_CAPS404};405 406#define MIN_LRU_BATCH BITS_PER_LONG407#define MAX_LRU_BATCH (MIN_LRU_BATCH * 64)408 409/* whether to keep historical stats from evicted generations */410#ifdef CONFIG_LRU_GEN_STATS411#define NR_HIST_GENS MAX_NR_GENS412#else413#define NR_HIST_GENS 1U414#endif415 416/*417 * The youngest generation number is stored in max_seq for both anon and file418 * types as they are aged on an equal footing. The oldest generation numbers are419 * stored in min_seq[] separately for anon and file types as clean file pages420 * can be evicted regardless of swap constraints.421 *422 * Normally anon and file min_seq are in sync. But if swapping is constrained,423 * e.g., out of swap space, file min_seq is allowed to advance and leave anon424 * min_seq behind.425 *426 * The number of pages in each generation is eventually consistent and therefore427 * can be transiently negative when reset_batch_size() is pending.428 */429struct lru_gen_folio {430 /* the aging increments the youngest generation number */431 unsigned long max_seq;432 /* the eviction increments the oldest generation numbers */433 unsigned long min_seq[ANON_AND_FILE];434 /* the birth time of each generation in jiffies */435 unsigned long timestamps[MAX_NR_GENS];436 /* the multi-gen LRU lists, lazily sorted on eviction */437 struct list_head folios[MAX_NR_GENS][ANON_AND_FILE][MAX_NR_ZONES];438 /* the multi-gen LRU sizes, eventually consistent */439 long nr_pages[MAX_NR_GENS][ANON_AND_FILE][MAX_NR_ZONES];440 /* the exponential moving average of refaulted */441 unsigned long avg_refaulted[ANON_AND_FILE][MAX_NR_TIERS];442 /* the exponential moving average of evicted+protected */443 unsigned long avg_total[ANON_AND_FILE][MAX_NR_TIERS];444 /* the first tier doesn't need protection, hence the minus one */445 unsigned long protected[NR_HIST_GENS][ANON_AND_FILE][MAX_NR_TIERS - 1];446 /* can be modified without holding the LRU lock */447 atomic_long_t evicted[NR_HIST_GENS][ANON_AND_FILE][MAX_NR_TIERS];448 atomic_long_t refaulted[NR_HIST_GENS][ANON_AND_FILE][MAX_NR_TIERS];449 /* whether the multi-gen LRU is enabled */450 bool enabled;451 /* the memcg generation this lru_gen_folio belongs to */452 u8 gen;453 /* the list segment this lru_gen_folio belongs to */454 u8 seg;455 /* per-node lru_gen_folio list for global reclaim */456 struct hlist_nulls_node list;457};458 459enum {460 MM_LEAF_TOTAL, /* total leaf entries */461 MM_LEAF_YOUNG, /* young leaf entries */462 MM_NONLEAF_FOUND, /* non-leaf entries found in Bloom filters */463 MM_NONLEAF_ADDED, /* non-leaf entries added to Bloom filters */464 NR_MM_STATS465};466 467/* double-buffering Bloom filters */468#define NR_BLOOM_FILTERS 2469 470struct lru_gen_mm_state {471 /* synced with max_seq after each iteration */472 unsigned long seq;473 /* where the current iteration continues after */474 struct list_head *head;475 /* where the last iteration ended before */476 struct list_head *tail;477 /* Bloom filters flip after each iteration */478 unsigned long *filters[NR_BLOOM_FILTERS];479 /* the mm stats for debugging */480 unsigned long stats[NR_HIST_GENS][NR_MM_STATS];481};482 483struct lru_gen_mm_walk {484 /* the lruvec under reclaim */485 struct lruvec *lruvec;486 /* max_seq from lru_gen_folio: can be out of date */487 unsigned long seq;488 /* the next address within an mm to scan */489 unsigned long next_addr;490 /* to batch promoted pages */491 int nr_pages[MAX_NR_GENS][ANON_AND_FILE][MAX_NR_ZONES];492 /* to batch the mm stats */493 int mm_stats[NR_MM_STATS];494 /* total batched items */495 int batched;496 bool can_swap;497 bool force_scan;498};499 500/*501 * For each node, memcgs are divided into two generations: the old and the502 * young. For each generation, memcgs are randomly sharded into multiple bins503 * to improve scalability. For each bin, the hlist_nulls is virtually divided504 * into three segments: the head, the tail and the default.505 *506 * An onlining memcg is added to the tail of a random bin in the old generation.507 * The eviction starts at the head of a random bin in the old generation. The508 * per-node memcg generation counter, whose reminder (mod MEMCG_NR_GENS) indexes509 * the old generation, is incremented when all its bins become empty.510 *511 * There are four operations:512 * 1. MEMCG_LRU_HEAD, which moves a memcg to the head of a random bin in its513 * current generation (old or young) and updates its "seg" to "head";514 * 2. MEMCG_LRU_TAIL, which moves a memcg to the tail of a random bin in its515 * current generation (old or young) and updates its "seg" to "tail";516 * 3. MEMCG_LRU_OLD, which moves a memcg to the head of a random bin in the old517 * generation, updates its "gen" to "old" and resets its "seg" to "default";518 * 4. MEMCG_LRU_YOUNG, which moves a memcg to the tail of a random bin in the519 * young generation, updates its "gen" to "young" and resets its "seg" to520 * "default".521 *522 * The events that trigger the above operations are:523 * 1. Exceeding the soft limit, which triggers MEMCG_LRU_HEAD;524 * 2. The first attempt to reclaim a memcg below low, which triggers525 * MEMCG_LRU_TAIL;526 * 3. The first attempt to reclaim a memcg offlined or below reclaimable size527 * threshold, which triggers MEMCG_LRU_TAIL;528 * 4. The second attempt to reclaim a memcg offlined or below reclaimable size529 * threshold, which triggers MEMCG_LRU_YOUNG;530 * 5. Attempting to reclaim a memcg below min, which triggers MEMCG_LRU_YOUNG;531 * 6. Finishing the aging on the eviction path, which triggers MEMCG_LRU_YOUNG;532 * 7. Offlining a memcg, which triggers MEMCG_LRU_OLD.533 *534 * Notes:535 * 1. Memcg LRU only applies to global reclaim, and the round-robin incrementing536 * of their max_seq counters ensures the eventual fairness to all eligible537 * memcgs. For memcg reclaim, it still relies on mem_cgroup_iter().538 * 2. There are only two valid generations: old (seq) and young (seq+1).539 * MEMCG_NR_GENS is set to three so that when reading the generation counter540 * locklessly, a stale value (seq-1) does not wraparound to young.541 */542#define MEMCG_NR_GENS 3543#define MEMCG_NR_BINS 8544 545struct lru_gen_memcg {546 /* the per-node memcg generation counter */547 unsigned long seq;548 /* each memcg has one lru_gen_folio per node */549 unsigned long nr_memcgs[MEMCG_NR_GENS];550 /* per-node lru_gen_folio list for global reclaim */551 struct hlist_nulls_head fifo[MEMCG_NR_GENS][MEMCG_NR_BINS];552 /* protects the above */553 spinlock_t lock;554};555 556void lru_gen_init_pgdat(struct pglist_data *pgdat);557void lru_gen_init_lruvec(struct lruvec *lruvec);558bool lru_gen_look_around(struct page_vma_mapped_walk *pvmw);559 560void lru_gen_init_memcg(struct mem_cgroup *memcg);561void lru_gen_exit_memcg(struct mem_cgroup *memcg);562void lru_gen_online_memcg(struct mem_cgroup *memcg);563void lru_gen_offline_memcg(struct mem_cgroup *memcg);564void lru_gen_release_memcg(struct mem_cgroup *memcg);565void lru_gen_soft_reclaim(struct mem_cgroup *memcg, int nid);566 567#else /* !CONFIG_LRU_GEN */568 569static inline void lru_gen_init_pgdat(struct pglist_data *pgdat)570{571}572 573static inline void lru_gen_init_lruvec(struct lruvec *lruvec)574{575}576 577static inline bool lru_gen_look_around(struct page_vma_mapped_walk *pvmw)578{579 return false;580}581 582static inline void lru_gen_init_memcg(struct mem_cgroup *memcg)583{584}585 586static inline void lru_gen_exit_memcg(struct mem_cgroup *memcg)587{588}589 590static inline void lru_gen_online_memcg(struct mem_cgroup *memcg)591{592}593 594static inline void lru_gen_offline_memcg(struct mem_cgroup *memcg)595{596}597 598static inline void lru_gen_release_memcg(struct mem_cgroup *memcg)599{600}601 602static inline void lru_gen_soft_reclaim(struct mem_cgroup *memcg, int nid)603{604}605 606#endif /* CONFIG_LRU_GEN */607 608struct lruvec {609 struct list_head lists[NR_LRU_LISTS];610 /* per lruvec lru_lock for memcg */611 spinlock_t lru_lock;612 /*613 * These track the cost of reclaiming one LRU - file or anon -614 * over the other. As the observed cost of reclaiming one LRU615 * increases, the reclaim scan balance tips toward the other.616 */617 unsigned long anon_cost;618 unsigned long file_cost;619 /* Non-resident age, driven by LRU movement */620 atomic_long_t nonresident_age;621 /* Refaults at the time of last reclaim cycle */622 unsigned long refaults[ANON_AND_FILE];623 /* Various lruvec state flags (enum lruvec_flags) */624 unsigned long flags;625#ifdef CONFIG_LRU_GEN626 /* evictable pages divided into generations */627 struct lru_gen_folio lrugen;628#ifdef CONFIG_LRU_GEN_WALKS_MMU629 /* to concurrently iterate lru_gen_mm_list */630 struct lru_gen_mm_state mm_state;631#endif632#endif /* CONFIG_LRU_GEN */633#ifdef CONFIG_MEMCG634 struct pglist_data *pgdat;635#endif636 struct zswap_lruvec_state zswap_lruvec_state;637};638 639/* Isolate for asynchronous migration */640#define ISOLATE_ASYNC_MIGRATE ((__force isolate_mode_t)0x4)641/* Isolate unevictable pages */642#define ISOLATE_UNEVICTABLE ((__force isolate_mode_t)0x8)643 644/* LRU Isolation modes. */645typedef unsigned __bitwise isolate_mode_t;646 647enum zone_watermarks {648 WMARK_MIN,649 WMARK_LOW,650 WMARK_HIGH,651 WMARK_PROMO,652 NR_WMARK653};654 655/*656 * One per migratetype for each PAGE_ALLOC_COSTLY_ORDER. Two additional lists657 * are added for THP. One PCP list is used by GPF_MOVABLE, and the other PCP list658 * is used by GFP_UNMOVABLE and GFP_RECLAIMABLE.659 */660#ifdef CONFIG_TRANSPARENT_HUGEPAGE661#define NR_PCP_THP 2662#else663#define NR_PCP_THP 0664#endif665#define NR_LOWORDER_PCP_LISTS (MIGRATE_PCPTYPES * (PAGE_ALLOC_COSTLY_ORDER + 1))666#define NR_PCP_LISTS (NR_LOWORDER_PCP_LISTS + NR_PCP_THP)667 668/*669 * Flags used in pcp->flags field.670 *671 * PCPF_PREV_FREE_HIGH_ORDER: a high-order page is freed in the672 * previous page freeing. To avoid to drain PCP for an accident673 * high-order page freeing.674 *675 * PCPF_FREE_HIGH_BATCH: preserve "pcp->batch" pages in PCP before676 * draining PCP for consecutive high-order pages freeing without677 * allocation if data cache slice of CPU is large enough. To reduce678 * zone lock contention and keep cache-hot pages reusing.679 */680#define PCPF_PREV_FREE_HIGH_ORDER BIT(0)681#define PCPF_FREE_HIGH_BATCH BIT(1)682 683struct per_cpu_pages {684 spinlock_t lock; /* Protects lists field */685 int count; /* number of pages in the list */686 int high; /* high watermark, emptying needed */687 int high_min; /* min high watermark */688 int high_max; /* max high watermark */689 int batch; /* chunk size for buddy add/remove */690 u8 flags; /* protected by pcp->lock */691 u8 alloc_factor; /* batch scaling factor during allocate */692#ifdef CONFIG_NUMA693 u8 expire; /* When 0, remote pagesets are drained */694#endif695 short free_count; /* consecutive free count */696 697 /* Lists of pages, one per migrate type stored on the pcp-lists */698 struct list_head lists[NR_PCP_LISTS];699} ____cacheline_aligned_in_smp;700 701struct per_cpu_zonestat {702#ifdef CONFIG_SMP703 s8 vm_stat_diff[NR_VM_ZONE_STAT_ITEMS];704 s8 stat_threshold;705#endif706#ifdef CONFIG_NUMA707 /*708 * Low priority inaccurate counters that are only folded709 * on demand. Use a large type to avoid the overhead of710 * folding during refresh_cpu_vm_stats.711 */712 unsigned long vm_numa_event[NR_VM_NUMA_EVENT_ITEMS];713#endif714};715 716struct per_cpu_nodestat {717 s8 stat_threshold;718 s8 vm_node_stat_diff[NR_VM_NODE_STAT_ITEMS];719};720 721#endif /* !__GENERATING_BOUNDS.H */722 723enum zone_type {724 /*725 * ZONE_DMA and ZONE_DMA32 are used when there are peripherals not able726 * to DMA to all of the addressable memory (ZONE_NORMAL).727 * On architectures where this area covers the whole 32 bit address728 * space ZONE_DMA32 is used. ZONE_DMA is left for the ones with smaller729 * DMA addressing constraints. This distinction is important as a 32bit730 * DMA mask is assumed when ZONE_DMA32 is defined. Some 64-bit731 * platforms may need both zones as they support peripherals with732 * different DMA addressing limitations.733 */734#ifdef CONFIG_ZONE_DMA735 ZONE_DMA,736#endif737#ifdef CONFIG_ZONE_DMA32738 ZONE_DMA32,739#endif740 /*741 * Normal addressable memory is in ZONE_NORMAL. DMA operations can be742 * performed on pages in ZONE_NORMAL if the DMA devices support743 * transfers to all addressable memory.744 */745 ZONE_NORMAL,746#ifdef CONFIG_HIGHMEM747 /*748 * A memory area that is only addressable by the kernel through749 * mapping portions into its own address space. This is for example750 * used by i386 to allow the kernel to address the memory beyond751 * 900MB. The kernel will set up special mappings (page752 * table entries on i386) for each page that the kernel needs to753 * access.754 */755 ZONE_HIGHMEM,756#endif757 /*758 * ZONE_MOVABLE is similar to ZONE_NORMAL, except that it contains759 * movable pages with few exceptional cases described below. Main use760 * cases for ZONE_MOVABLE are to make memory offlining/unplug more761 * likely to succeed, and to locally limit unmovable allocations - e.g.,762 * to increase the number of THP/huge pages. Notable special cases are:763 *764 * 1. Pinned pages: (long-term) pinning of movable pages might765 * essentially turn such pages unmovable. Therefore, we do not allow766 * pinning long-term pages in ZONE_MOVABLE. When pages are pinned and767 * faulted, they come from the right zone right away. However, it is768 * still possible that address space already has pages in769 * ZONE_MOVABLE at the time when pages are pinned (i.e. user has770 * touches that memory before pinning). In such case we migrate them771 * to a different zone. When migration fails - pinning fails.772 * 2. memblock allocations: kernelcore/movablecore setups might create773 * situations where ZONE_MOVABLE contains unmovable allocations774 * after boot. Memory offlining and allocations fail early.775 * 3. Memory holes: kernelcore/movablecore setups might create very rare776 * situations where ZONE_MOVABLE contains memory holes after boot,777 * for example, if we have sections that are only partially778 * populated. Memory offlining and allocations fail early.779 * 4. PG_hwpoison pages: while poisoned pages can be skipped during780 * memory offlining, such pages cannot be allocated.781 * 5. Unmovable PG_offline pages: in paravirtualized environments,782 * hotplugged memory blocks might only partially be managed by the783 * buddy (e.g., via XEN-balloon, Hyper-V balloon, virtio-mem). The784 * parts not manged by the buddy are unmovable PG_offline pages. In785 * some cases (virtio-mem), such pages can be skipped during786 * memory offlining, however, cannot be moved/allocated. These787 * techniques might use alloc_contig_range() to hide previously788 * exposed pages from the buddy again (e.g., to implement some sort789 * of memory unplug in virtio-mem).790 * 6. ZERO_PAGE(0), kernelcore/movablecore setups might create791 * situations where ZERO_PAGE(0) which is allocated differently792 * on different platforms may end up in a movable zone. ZERO_PAGE(0)793 * cannot be migrated.794 * 7. Memory-hotplug: when using memmap_on_memory and onlining the795 * memory to the MOVABLE zone, the vmemmap pages are also placed in796 * such zone. Such pages cannot be really moved around as they are797 * self-stored in the range, but they are treated as movable when798 * the range they describe is about to be offlined.799 *800 * In general, no unmovable allocations that degrade memory offlining801 * should end up in ZONE_MOVABLE. Allocators (like alloc_contig_range())802 * have to expect that migrating pages in ZONE_MOVABLE can fail (even803 * if has_unmovable_pages() states that there are no unmovable pages,804 * there can be false negatives).805 */806 ZONE_MOVABLE,807#ifdef CONFIG_ZONE_DEVICE808 ZONE_DEVICE,809#endif810 __MAX_NR_ZONES811 812};813 814#ifndef __GENERATING_BOUNDS_H815 816#define ASYNC_AND_SYNC 2817 818struct zone {819 /* Read-mostly fields */820 821 /* zone watermarks, access with *_wmark_pages(zone) macros */822 unsigned long _watermark[NR_WMARK];823 unsigned long watermark_boost;824 825 unsigned long nr_reserved_highatomic;826 unsigned long nr_free_highatomic;827 828 /*829 * We don't know if the memory that we're going to allocate will be830 * freeable or/and it will be released eventually, so to avoid totally831 * wasting several GB of ram we must reserve some of the lower zone832 * memory (otherwise we risk to run OOM on the lower zones despite833 * there being tons of freeable ram on the higher zones). This array is834 * recalculated at runtime if the sysctl_lowmem_reserve_ratio sysctl835 * changes.836 */837 long lowmem_reserve[MAX_NR_ZONES];838 839#ifdef CONFIG_NUMA840 int node;841#endif842 struct pglist_data *zone_pgdat;843 struct per_cpu_pages __percpu *per_cpu_pageset;844 struct per_cpu_zonestat __percpu *per_cpu_zonestats;845 /*846 * the high and batch values are copied to individual pagesets for847 * faster access848 */849 int pageset_high_min;850 int pageset_high_max;851 int pageset_batch;852 853#ifndef CONFIG_SPARSEMEM854 /*855 * Flags for a pageblock_nr_pages block. See pageblock-flags.h.856 * In SPARSEMEM, this map is stored in struct mem_section857 */858 unsigned long *pageblock_flags;859#endif /* CONFIG_SPARSEMEM */860 861 /* zone_start_pfn == zone_start_paddr >> PAGE_SHIFT */862 unsigned long zone_start_pfn;863 864 /*865 * spanned_pages is the total pages spanned by the zone, including866 * holes, which is calculated as:867 * spanned_pages = zone_end_pfn - zone_start_pfn;868 *869 * present_pages is physical pages existing within the zone, which870 * is calculated as:871 * present_pages = spanned_pages - absent_pages(pages in holes);872 *873 * present_early_pages is present pages existing within the zone874 * located on memory available since early boot, excluding hotplugged875 * memory.876 *877 * managed_pages is present pages managed by the buddy system, which878 * is calculated as (reserved_pages includes pages allocated by the879 * bootmem allocator):880 * managed_pages = present_pages - reserved_pages;881 *882 * cma pages is present pages that are assigned for CMA use883 * (MIGRATE_CMA).884 *885 * So present_pages may be used by memory hotplug or memory power886 * management logic to figure out unmanaged pages by checking887 * (present_pages - managed_pages). And managed_pages should be used888 * by page allocator and vm scanner to calculate all kinds of watermarks889 * and thresholds.890 *891 * Locking rules:892 *893 * zone_start_pfn and spanned_pages are protected by span_seqlock.894 * It is a seqlock because it has to be read outside of zone->lock,895 * and it is done in the main allocator path. But, it is written896 * quite infrequently.897 *898 * The span_seq lock is declared along with zone->lock because it is899 * frequently read in proximity to zone->lock. It's good to900 * give them a chance of being in the same cacheline.901 *902 * Write access to present_pages at runtime should be protected by903 * mem_hotplug_begin/done(). Any reader who can't tolerant drift of904 * present_pages should use get_online_mems() to get a stable value.905 */906 atomic_long_t managed_pages;907 unsigned long spanned_pages;908 unsigned long present_pages;909#if defined(CONFIG_MEMORY_HOTPLUG)910 unsigned long present_early_pages;911#endif912#ifdef CONFIG_CMA913 unsigned long cma_pages;914#endif915 916 const char *name;917 918#ifdef CONFIG_MEMORY_ISOLATION919 /*920 * Number of isolated pageblock. It is used to solve incorrect921 * freepage counting problem due to racy retrieving migratetype922 * of pageblock. Protected by zone->lock.923 */924 unsigned long nr_isolate_pageblock;925#endif926 927#ifdef CONFIG_MEMORY_HOTPLUG928 /* see spanned/present_pages for more description */929 seqlock_t span_seqlock;930#endif931 932 int initialized;933 934 /* Write-intensive fields used from the page allocator */935 CACHELINE_PADDING(_pad1_);936 937 /* free areas of different sizes */938 struct free_area free_area[NR_PAGE_ORDERS];939 940#ifdef CONFIG_UNACCEPTED_MEMORY941 /* Pages to be accepted. All pages on the list are MAX_PAGE_ORDER */942 struct list_head unaccepted_pages;943#endif944 945 /* zone flags, see below */946 unsigned long flags;947 948 /* Primarily protects free_area */949 spinlock_t lock;950 951 /* Write-intensive fields used by compaction and vmstats. */952 CACHELINE_PADDING(_pad2_);953 954 /*955 * When free pages are below this point, additional steps are taken956 * when reading the number of free pages to avoid per-cpu counter957 * drift allowing watermarks to be breached958 */959 unsigned long percpu_drift_mark;960 961#if defined CONFIG_COMPACTION || defined CONFIG_CMA962 /* pfn where compaction free scanner should start */963 unsigned long compact_cached_free_pfn;964 /* pfn where compaction migration scanner should start */965 unsigned long compact_cached_migrate_pfn[ASYNC_AND_SYNC];966 unsigned long compact_init_migrate_pfn;967 unsigned long compact_init_free_pfn;968#endif969 970#ifdef CONFIG_COMPACTION971 /*972 * On compaction failure, 1<<compact_defer_shift compactions973 * are skipped before trying again. The number attempted since974 * last failure is tracked with compact_considered.975 * compact_order_failed is the minimum compaction failed order.976 */977 unsigned int compact_considered;978 unsigned int compact_defer_shift;979 int compact_order_failed;980#endif981 982#if defined CONFIG_COMPACTION || defined CONFIG_CMA983 /* Set to true when the PG_migrate_skip bits should be cleared */984 bool compact_blockskip_flush;985#endif986 987 bool contiguous;988 989 CACHELINE_PADDING(_pad3_);990 /* Zone statistics */991 atomic_long_t vm_stat[NR_VM_ZONE_STAT_ITEMS];992 atomic_long_t vm_numa_event[NR_VM_NUMA_EVENT_ITEMS];993} ____cacheline_internodealigned_in_smp;994 995enum pgdat_flags {996 PGDAT_DIRTY, /* reclaim scanning has recently found997 * many dirty file pages at the tail998 * of the LRU.999 */1000 PGDAT_WRITEBACK, /* reclaim scanning has recently found1001 * many pages under writeback1002 */1003 PGDAT_RECLAIM_LOCKED, /* prevents concurrent reclaim */1004};1005 1006enum zone_flags {1007 ZONE_BOOSTED_WATERMARK, /* zone recently boosted watermarks.1008 * Cleared when kswapd is woken.1009 */1010 ZONE_RECLAIM_ACTIVE, /* kswapd may be scanning the zone. */1011 ZONE_BELOW_HIGH, /* zone is below high watermark. */1012};1013 1014static inline unsigned long wmark_pages(const struct zone *z,1015 enum zone_watermarks w)1016{1017 return z->_watermark[w] + z->watermark_boost;1018}1019 1020static inline unsigned long min_wmark_pages(const struct zone *z)1021{1022 return wmark_pages(z, WMARK_MIN);1023}1024 1025static inline unsigned long low_wmark_pages(const struct zone *z)1026{1027 return wmark_pages(z, WMARK_LOW);1028}1029 1030static inline unsigned long high_wmark_pages(const struct zone *z)1031{1032 return wmark_pages(z, WMARK_HIGH);1033}1034 1035static inline unsigned long promo_wmark_pages(const struct zone *z)1036{1037 return wmark_pages(z, WMARK_PROMO);1038}1039 1040static inline unsigned long zone_managed_pages(struct zone *zone)1041{1042 return (unsigned long)atomic_long_read(&zone->managed_pages);1043}1044 1045static inline unsigned long zone_cma_pages(struct zone *zone)1046{1047#ifdef CONFIG_CMA1048 return zone->cma_pages;1049#else1050 return 0;1051#endif1052}1053 1054static inline unsigned long zone_end_pfn(const struct zone *zone)1055{1056 return zone->zone_start_pfn + zone->spanned_pages;1057}1058 1059static inline bool zone_spans_pfn(const struct zone *zone, unsigned long pfn)1060{1061 return zone->zone_start_pfn <= pfn && pfn < zone_end_pfn(zone);1062}1063 1064static inline bool zone_is_initialized(struct zone *zone)1065{1066 return zone->initialized;1067}1068 1069static inline bool zone_is_empty(struct zone *zone)1070{1071 return zone->spanned_pages == 0;1072}1073 1074#ifndef BUILD_VDSO32_641075/*1076 * The zone field is never updated after free_area_init_core()1077 * sets it, so none of the operations on it need to be atomic.1078 */1079 1080/* Page flags: | [SECTION] | [NODE] | ZONE | [LAST_CPUPID] | ... | FLAGS | */1081#define SECTIONS_PGOFF ((sizeof(unsigned long)*8) - SECTIONS_WIDTH)1082#define NODES_PGOFF (SECTIONS_PGOFF - NODES_WIDTH)1083#define ZONES_PGOFF (NODES_PGOFF - ZONES_WIDTH)1084#define LAST_CPUPID_PGOFF (ZONES_PGOFF - LAST_CPUPID_WIDTH)1085#define KASAN_TAG_PGOFF (LAST_CPUPID_PGOFF - KASAN_TAG_WIDTH)1086#define LRU_GEN_PGOFF (KASAN_TAG_PGOFF - LRU_GEN_WIDTH)1087#define LRU_REFS_PGOFF (LRU_GEN_PGOFF - LRU_REFS_WIDTH)1088 1089/*1090 * Define the bit shifts to access each section. For non-existent1091 * sections we define the shift as 0; that plus a 0 mask ensures1092 * the compiler will optimise away reference to them.1093 */1094#define SECTIONS_PGSHIFT (SECTIONS_PGOFF * (SECTIONS_WIDTH != 0))1095#define NODES_PGSHIFT (NODES_PGOFF * (NODES_WIDTH != 0))1096#define ZONES_PGSHIFT (ZONES_PGOFF * (ZONES_WIDTH != 0))1097#define LAST_CPUPID_PGSHIFT (LAST_CPUPID_PGOFF * (LAST_CPUPID_WIDTH != 0))1098#define KASAN_TAG_PGSHIFT (KASAN_TAG_PGOFF * (KASAN_TAG_WIDTH != 0))1099 1100/* NODE:ZONE or SECTION:ZONE is used to ID a zone for the buddy allocator */1101#ifdef NODE_NOT_IN_PAGE_FLAGS1102#define ZONEID_SHIFT (SECTIONS_SHIFT + ZONES_SHIFT)1103#define ZONEID_PGOFF ((SECTIONS_PGOFF < ZONES_PGOFF) ? \1104 SECTIONS_PGOFF : ZONES_PGOFF)1105#else1106#define ZONEID_SHIFT (NODES_SHIFT + ZONES_SHIFT)1107#define ZONEID_PGOFF ((NODES_PGOFF < ZONES_PGOFF) ? \1108 NODES_PGOFF : ZONES_PGOFF)1109#endif1110 1111#define ZONEID_PGSHIFT (ZONEID_PGOFF * (ZONEID_SHIFT != 0))1112 1113#define ZONES_MASK ((1UL << ZONES_WIDTH) - 1)1114#define NODES_MASK ((1UL << NODES_WIDTH) - 1)1115#define SECTIONS_MASK ((1UL << SECTIONS_WIDTH) - 1)1116#define LAST_CPUPID_MASK ((1UL << LAST_CPUPID_SHIFT) - 1)1117#define KASAN_TAG_MASK ((1UL << KASAN_TAG_WIDTH) - 1)1118#define ZONEID_MASK ((1UL << ZONEID_SHIFT) - 1)1119 1120static inline enum zone_type page_zonenum(const struct page *page)1121{1122 ASSERT_EXCLUSIVE_BITS(page->flags, ZONES_MASK << ZONES_PGSHIFT);1123 return (page->flags >> ZONES_PGSHIFT) & ZONES_MASK;1124}1125 1126static inline enum zone_type folio_zonenum(const struct folio *folio)1127{1128 return page_zonenum(&folio->page);1129}1130 1131#ifdef CONFIG_ZONE_DEVICE1132static inline bool is_zone_device_page(const struct page *page)1133{1134 return page_zonenum(page) == ZONE_DEVICE;1135}1136 1137/*1138 * Consecutive zone device pages should not be merged into the same sgl1139 * or bvec segment with other types of pages or if they belong to different1140 * pgmaps. Otherwise getting the pgmap of a given segment is not possible1141 * without scanning the entire segment. This helper returns true either if1142 * both pages are not zone device pages or both pages are zone device pages1143 * with the same pgmap.1144 */1145static inline bool zone_device_pages_have_same_pgmap(const struct page *a,1146 const struct page *b)1147{1148 if (is_zone_device_page(a) != is_zone_device_page(b))1149 return false;1150 if (!is_zone_device_page(a))1151 return true;1152 return a->pgmap == b->pgmap;1153}1154 1155extern void memmap_init_zone_device(struct zone *, unsigned long,1156 unsigned long, struct dev_pagemap *);1157#else1158static inline bool is_zone_device_page(const struct page *page)1159{1160 return false;1161}1162static inline bool zone_device_pages_have_same_pgmap(const struct page *a,1163 const struct page *b)1164{1165 return true;1166}1167#endif1168 1169static inline bool folio_is_zone_device(const struct folio *folio)1170{1171 return is_zone_device_page(&folio->page);1172}1173 1174static inline bool is_zone_movable_page(const struct page *page)1175{1176 return page_zonenum(page) == ZONE_MOVABLE;1177}1178 1179static inline bool folio_is_zone_movable(const struct folio *folio)1180{1181 return folio_zonenum(folio) == ZONE_MOVABLE;1182}1183#endif1184 1185/*1186 * Return true if [start_pfn, start_pfn + nr_pages) range has a non-empty1187 * intersection with the given zone1188 */1189static inline bool zone_intersects(struct zone *zone,1190 unsigned long start_pfn, unsigned long nr_pages)1191{1192 if (zone_is_empty(zone))1193 return false;1194 if (start_pfn >= zone_end_pfn(zone) ||1195 start_pfn + nr_pages <= zone->zone_start_pfn)1196 return false;1197 1198 return true;1199}1200 1201/*1202 * The "priority" of VM scanning is how much of the queues we will scan in one1203 * go. A value of 12 for DEF_PRIORITY implies that we will scan 1/4096th of the1204 * queues ("queue_length >> 12") during an aging round.1205 */1206#define DEF_PRIORITY 121207 1208/* Maximum number of zones on a zonelist */1209#define MAX_ZONES_PER_ZONELIST (MAX_NUMNODES * MAX_NR_ZONES)1210 1211enum {1212 ZONELIST_FALLBACK, /* zonelist with fallback */1213#ifdef CONFIG_NUMA1214 /*1215 * The NUMA zonelists are doubled because we need zonelists that1216 * restrict the allocations to a single node for __GFP_THISNODE.1217 */1218 ZONELIST_NOFALLBACK, /* zonelist without fallback (__GFP_THISNODE) */1219#endif1220 MAX_ZONELISTS1221};1222 1223/*1224 * This struct contains information about a zone in a zonelist. It is stored1225 * here to avoid dereferences into large structures and lookups of tables1226 */1227struct zoneref {1228 struct zone *zone; /* Pointer to actual zone */1229 int zone_idx; /* zone_idx(zoneref->zone) */1230};1231 1232/*1233 * One allocation request operates on a zonelist. A zonelist1234 * is a list of zones, the first one is the 'goal' of the1235 * allocation, the other zones are fallback zones, in decreasing1236 * priority.1237 *1238 * To speed the reading of the zonelist, the zonerefs contain the zone index1239 * of the entry being read. Helper functions to access information given1240 * a struct zoneref are1241 *1242 * zonelist_zone() - Return the struct zone * for an entry in _zonerefs1243 * zonelist_zone_idx() - Return the index of the zone for an entry1244 * zonelist_node_idx() - Return the index of the node for an entry1245 */1246struct zonelist {1247 struct zoneref _zonerefs[MAX_ZONES_PER_ZONELIST + 1];1248};1249 1250/*1251 * The array of struct pages for flatmem.1252 * It must be declared for SPARSEMEM as well because there are configurations1253 * that rely on that.1254 */1255extern struct page *mem_map;1256 1257#ifdef CONFIG_TRANSPARENT_HUGEPAGE1258struct deferred_split {1259 spinlock_t split_queue_lock;1260 struct list_head split_queue;1261 unsigned long split_queue_len;1262};1263#endif1264 1265#ifdef CONFIG_MEMORY_FAILURE1266/*1267 * Per NUMA node memory failure handling statistics.1268 */1269struct memory_failure_stats {1270 /*1271 * Number of raw pages poisoned.1272 * Cases not accounted: memory outside kernel control, offline page,1273 * arch-specific memory_failure (SGX), hwpoison_filter() filtered1274 * error events, and unpoison actions from hwpoison_unpoison.1275 */1276 unsigned long total;1277 /*1278 * Recovery results of poisoned raw pages handled by memory_failure,1279 * in sync with mf_result.1280 * total = ignored + failed + delayed + recovered.1281 * total * PAGE_SIZE * #nodes = /proc/meminfo/HardwareCorrupted.1282 */1283 unsigned long ignored;1284 unsigned long failed;1285 unsigned long delayed;1286 unsigned long recovered;1287};1288#endif1289 1290/*1291 * On NUMA machines, each NUMA node would have a pg_data_t to describe1292 * it's memory layout. On UMA machines there is a single pglist_data which1293 * describes the whole memory.1294 *1295 * Memory statistics and page replacement data structures are maintained on a1296 * per-zone basis.1297 */1298typedef struct pglist_data {1299 /*1300 * node_zones contains just the zones for THIS node. Not all of the1301 * zones may be populated, but it is the full list. It is referenced by1302 * this node's node_zonelists as well as other node's node_zonelists.1303 */1304 struct zone node_zones[MAX_NR_ZONES];1305 1306 /*1307 * node_zonelists contains references to all zones in all nodes.1308 * Generally the first zones will be references to this node's1309 * node_zones.1310 */1311 struct zonelist node_zonelists[MAX_ZONELISTS];1312 1313 int nr_zones; /* number of populated zones in this node */1314#ifdef CONFIG_FLATMEM /* means !SPARSEMEM */1315 struct page *node_mem_map;1316#ifdef CONFIG_PAGE_EXTENSION1317 struct page_ext *node_page_ext;1318#endif1319#endif1320#if defined(CONFIG_MEMORY_HOTPLUG) || defined(CONFIG_DEFERRED_STRUCT_PAGE_INIT)1321 /*1322 * Must be held any time you expect node_start_pfn,1323 * node_present_pages, node_spanned_pages or nr_zones to stay constant.1324 * Also synchronizes pgdat->first_deferred_pfn during deferred page1325 * init.1326 *1327 * pgdat_resize_lock() and pgdat_resize_unlock() are provided to1328 * manipulate node_size_lock without checking for CONFIG_MEMORY_HOTPLUG1329 * or CONFIG_DEFERRED_STRUCT_PAGE_INIT.1330 *1331 * Nests above zone->lock and zone->span_seqlock1332 */1333 spinlock_t node_size_lock;1334#endif1335 unsigned long node_start_pfn;1336 unsigned long node_present_pages; /* total number of physical pages */1337 unsigned long node_spanned_pages; /* total size of physical page1338 range, including holes */1339 int node_id;1340 wait_queue_head_t kswapd_wait;1341 wait_queue_head_t pfmemalloc_wait;1342 1343 /* workqueues for throttling reclaim for different reasons. */1344 wait_queue_head_t reclaim_wait[NR_VMSCAN_THROTTLE];1345 1346 atomic_t nr_writeback_throttled;/* nr of writeback-throttled tasks */1347 unsigned long nr_reclaim_start; /* nr pages written while throttled1348 * when throttling started. */1349#ifdef CONFIG_MEMORY_HOTPLUG1350 struct mutex kswapd_lock;1351#endif1352 struct task_struct *kswapd; /* Protected by kswapd_lock */1353 int kswapd_order;1354 enum zone_type kswapd_highest_zoneidx;1355 1356 int kswapd_failures; /* Number of 'reclaimed == 0' runs */1357 1358#ifdef CONFIG_COMPACTION1359 int kcompactd_max_order;1360 enum zone_type kcompactd_highest_zoneidx;1361 wait_queue_head_t kcompactd_wait;1362 struct task_struct *kcompactd;1363 bool proactive_compact_trigger;1364#endif1365 /*1366 * This is a per-node reserve of pages that are not available1367 * to userspace allocations.1368 */1369 unsigned long totalreserve_pages;1370 1371#ifdef CONFIG_NUMA1372 /*1373 * node reclaim becomes active if more unmapped pages exist.1374 */1375 unsigned long min_unmapped_pages;1376 unsigned long min_slab_pages;1377#endif /* CONFIG_NUMA */1378 1379 /* Write-intensive fields used by page reclaim */1380 CACHELINE_PADDING(_pad1_);1381 1382#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT1383 /*1384 * If memory initialisation on large machines is deferred then this1385 * is the first PFN that needs to be initialised.1386 */1387 unsigned long first_deferred_pfn;1388#endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */1389 1390#ifdef CONFIG_TRANSPARENT_HUGEPAGE1391 struct deferred_split deferred_split_queue;1392#endif1393 1394#ifdef CONFIG_NUMA_BALANCING1395 /* start time in ms of current promote rate limit period */1396 unsigned int nbp_rl_start;1397 /* number of promote candidate pages at start time of current rate limit period */1398 unsigned long nbp_rl_nr_cand;1399 /* promote threshold in ms */1400 unsigned int nbp_threshold;1401 /* start time in ms of current promote threshold adjustment period */1402 unsigned int nbp_th_start;1403 /*1404 * number of promote candidate pages at start time of current promote1405 * threshold adjustment period1406 */1407 unsigned long nbp_th_nr_cand;1408#endif1409 /* Fields commonly accessed by the page reclaim scanner */1410 1411 /*1412 * NOTE: THIS IS UNUSED IF MEMCG IS ENABLED.1413 *1414 * Use mem_cgroup_lruvec() to look up lruvecs.1415 */1416 struct lruvec __lruvec;1417 1418 unsigned long flags;1419 1420#ifdef CONFIG_LRU_GEN1421 /* kswap mm walk data */1422 struct lru_gen_mm_walk mm_walk;1423 /* lru_gen_folio list */1424 struct lru_gen_memcg memcg_lru;1425#endif1426 1427 CACHELINE_PADDING(_pad2_);1428 1429 /* Per-node vmstats */1430 struct per_cpu_nodestat __percpu *per_cpu_nodestats;1431 atomic_long_t vm_stat[NR_VM_NODE_STAT_ITEMS];1432#ifdef CONFIG_NUMA1433 struct memory_tier __rcu *memtier;1434#endif1435#ifdef CONFIG_MEMORY_FAILURE1436 struct memory_failure_stats mf_stats;1437#endif1438} pg_data_t;1439 1440#define node_present_pages(nid) (NODE_DATA(nid)->node_present_pages)1441#define node_spanned_pages(nid) (NODE_DATA(nid)->node_spanned_pages)1442 1443#define node_start_pfn(nid) (NODE_DATA(nid)->node_start_pfn)1444#define node_end_pfn(nid) pgdat_end_pfn(NODE_DATA(nid))1445 1446static inline unsigned long pgdat_end_pfn(pg_data_t *pgdat)1447{1448 return pgdat->node_start_pfn + pgdat->node_spanned_pages;1449}1450 1451#include <linux/memory_hotplug.h>1452 1453void build_all_zonelists(pg_data_t *pgdat);1454void wakeup_kswapd(struct zone *zone, gfp_t gfp_mask, int order,1455 enum zone_type highest_zoneidx) HWJS_SUSPENDS;1456bool __zone_watermark_ok(struct zone *z, unsigned int order, unsigned long mark,1457 int highest_zoneidx, unsigned int alloc_flags,1458 long free_pages);1459bool zone_watermark_ok(struct zone *z, unsigned int order,1460 unsigned long mark, int highest_zoneidx,1461 unsigned int alloc_flags);1462bool zone_watermark_ok_safe(struct zone *z, unsigned int order,1463 unsigned long mark, int highest_zoneidx);1464/*1465 * Memory initialization context, use to differentiate memory added by1466 * the platform statically or via memory hotplug interface.1467 */1468enum meminit_context {1469 MEMINIT_EARLY,1470 MEMINIT_HOTPLUG,1471};1472 1473extern void init_currently_empty_zone(struct zone *zone, unsigned long start_pfn,1474 unsigned long size);1475 1476extern void lruvec_init(struct lruvec *lruvec);1477 1478static inline struct pglist_data *lruvec_pgdat(struct lruvec *lruvec)1479{1480#ifdef CONFIG_MEMCG1481 return lruvec->pgdat;1482#else1483 return container_of(lruvec, struct pglist_data, __lruvec);1484#endif1485}1486 1487#ifdef CONFIG_HAVE_MEMORYLESS_NODES1488int local_memory_node(int node_id);1489#else1490static inline int local_memory_node(int node_id) { return node_id; };1491#endif1492 1493/*1494 * zone_idx() returns 0 for the ZONE_DMA zone, 1 for the ZONE_NORMAL zone, etc.1495 */1496#define zone_idx(zone) ((zone) - (zone)->zone_pgdat->node_zones)1497 1498#ifdef CONFIG_ZONE_DEVICE1499static inline bool zone_is_zone_device(struct zone *zone)1500{1501 return zone_idx(zone) == ZONE_DEVICE;1502}1503#else1504static inline bool zone_is_zone_device(struct zone *zone)1505{1506 return false;1507}1508#endif1509 1510/*1511 * Returns true if a zone has pages managed by the buddy allocator.1512 * All the reclaim decisions have to use this function rather than1513 * populated_zone(). If the whole zone is reserved then we can easily1514 * end up with populated_zone() && !managed_zone().1515 */1516static inline bool managed_zone(struct zone *zone)1517{1518 return zone_managed_pages(zone);1519}1520 1521/* Returns true if a zone has memory */1522static inline bool populated_zone(struct zone *zone)1523{1524 return zone->present_pages;1525}1526 1527#ifdef CONFIG_NUMA1528static inline int zone_to_nid(struct zone *zone)1529{1530 return zone->node;1531}1532 1533static inline void zone_set_nid(struct zone *zone, int nid)1534{1535 zone->node = nid;1536}1537#else1538static inline int zone_to_nid(struct zone *zone)1539{1540 return 0;1541}1542 1543static inline void zone_set_nid(struct zone *zone, int nid) {}1544#endif1545 1546extern int movable_zone;1547 1548static inline int is_highmem_idx(enum zone_type idx)1549{1550#ifdef CONFIG_HIGHMEM1551 return (idx == ZONE_HIGHMEM ||1552 (idx == ZONE_MOVABLE && movable_zone == ZONE_HIGHMEM));1553#else1554 return 0;1555#endif1556}1557 1558/**1559 * is_highmem - helper function to quickly check if a struct zone is a1560 * highmem zone or not. This is an attempt to keep references1561 * to ZONE_{DMA/NORMAL/HIGHMEM/etc} in general code to a minimum.1562 * @zone: pointer to struct zone variable1563 * Return: 1 for a highmem zone, 0 otherwise1564 */1565static inline int is_highmem(struct zone *zone)1566{1567 return is_highmem_idx(zone_idx(zone));1568}1569 1570#ifdef CONFIG_ZONE_DMA1571bool has_managed_dma(void);1572#else1573static inline bool has_managed_dma(void)1574{1575 return false;1576}1577#endif1578 1579 1580#ifndef CONFIG_NUMA1581 1582extern struct pglist_data contig_page_data;1583static inline struct pglist_data *NODE_DATA(int nid)1584{1585 return &contig_page_data;1586}1587 1588#else /* CONFIG_NUMA */1589 1590#include <asm/mmzone.h>1591 1592#endif /* !CONFIG_NUMA */1593 1594extern struct pglist_data *first_online_pgdat(void);1595extern struct pglist_data *next_online_pgdat(struct pglist_data *pgdat);1596extern struct zone *next_zone(struct zone *zone);1597 1598/**1599 * for_each_online_pgdat - helper macro to iterate over all online nodes1600 * @pgdat: pointer to a pg_data_t variable1601 */1602#define for_each_online_pgdat(pgdat) \1603 for (pgdat = first_online_pgdat(); \1604 pgdat; \1605 pgdat = next_online_pgdat(pgdat))1606/**1607 * for_each_zone - helper macro to iterate over all memory zones1608 * @zone: pointer to struct zone variable1609 *1610 * The user only needs to declare the zone variable, for_each_zone1611 * fills it in.1612 */1613#define for_each_zone(zone) \1614 for (zone = (first_online_pgdat())->node_zones; \1615 zone; \1616 zone = next_zone(zone))1617 1618#define for_each_populated_zone(zone) \1619 for (zone = (first_online_pgdat())->node_zones; \1620 zone; \1621 zone = next_zone(zone)) \1622 if (!populated_zone(zone)) \1623 ; /* do nothing */ \1624 else1625 1626static inline struct zone *zonelist_zone(struct zoneref *zoneref)1627{1628 return zoneref->zone;1629}1630 1631static inline int zonelist_zone_idx(struct zoneref *zoneref)1632{1633 return zoneref->zone_idx;1634}1635 1636static inline int zonelist_node_idx(struct zoneref *zoneref)1637{1638 return zone_to_nid(zoneref->zone);1639}1640 1641struct zoneref *__next_zones_zonelist(struct zoneref *z,1642 enum zone_type highest_zoneidx,1643 nodemask_t *nodes);1644 1645/**1646 * next_zones_zonelist - Returns the next zone at or below highest_zoneidx within the allowed nodemask using a cursor within a zonelist as a starting point1647 * @z: The cursor used as a starting point for the search1648 * @highest_zoneidx: The zone index of the highest zone to return1649 * @nodes: An optional nodemask to filter the zonelist with1650 *1651 * This function returns the next zone at or below a given zone index that is1652 * within the allowed nodemask using a cursor as the starting point for the1653 * search. The zoneref returned is a cursor that represents the current zone1654 * being examined. It should be advanced by one before calling1655 * next_zones_zonelist again.1656 *1657 * Return: the next zone at or below highest_zoneidx within the allowed1658 * nodemask using a cursor within a zonelist as a starting point1659 */1660static __always_inline struct zoneref *next_zones_zonelist(struct zoneref *z,1661 enum zone_type highest_zoneidx,1662 nodemask_t *nodes)1663{1664 if (likely(!nodes && zonelist_zone_idx(z) <= highest_zoneidx))1665 return z;1666 return __next_zones_zonelist(z, highest_zoneidx, nodes);1667}1668 1669/**1670 * first_zones_zonelist - Returns the first zone at or below highest_zoneidx within the allowed nodemask in a zonelist1671 * @zonelist: The zonelist to search for a suitable zone1672 * @highest_zoneidx: The zone index of the highest zone to return1673 * @nodes: An optional nodemask to filter the zonelist with1674 *1675 * This function returns the first zone at or below a given zone index that is1676 * within the allowed nodemask. The zoneref returned is a cursor that can be1677 * used to iterate the zonelist with next_zones_zonelist by advancing it by1678 * one before calling.1679 *1680 * When no eligible zone is found, zoneref->zone is NULL (zoneref itself is1681 * never NULL). This may happen either genuinely, or due to concurrent nodemask1682 * update due to cpuset modification.1683 *1684 * Return: Zoneref pointer for the first suitable zone found1685 */1686static inline struct zoneref *first_zones_zonelist(struct zonelist *zonelist,1687 enum zone_type highest_zoneidx,1688 nodemask_t *nodes)1689{1690 return next_zones_zonelist(zonelist->_zonerefs,1691 highest_zoneidx, nodes);1692}1693 1694/**1695 * for_each_zone_zonelist_nodemask - helper macro to iterate over valid zones in a zonelist at or below a given zone index and within a nodemask1696 * @zone: The current zone in the iterator1697 * @z: The current pointer within zonelist->_zonerefs being iterated1698 * @zlist: The zonelist being iterated1699 * @highidx: The zone index of the highest zone to return1700 * @nodemask: Nodemask allowed by the allocator1701 *1702 * This iterator iterates though all zones at or below a given zone index and1703 * within a given nodemask1704 */1705#define for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, nodemask) \1706 for (z = first_zones_zonelist(zlist, highidx, nodemask), zone = zonelist_zone(z); \1707 zone; \1708 z = next_zones_zonelist(++z, highidx, nodemask), \1709 zone = zonelist_zone(z))1710 1711#define for_next_zone_zonelist_nodemask(zone, z, highidx, nodemask) \1712 for (zone = zonelist_zone(z); \1713 zone; \1714 z = next_zones_zonelist(++z, highidx, nodemask), \1715 zone = zonelist_zone(z))1716 1717 1718/**1719 * for_each_zone_zonelist - helper macro to iterate over valid zones in a zonelist at or below a given zone index1720 * @zone: The current zone in the iterator1721 * @z: The current pointer within zonelist->zones being iterated1722 * @zlist: The zonelist being iterated1723 * @highidx: The zone index of the highest zone to return1724 *1725 * This iterator iterates though all zones at or below a given zone index.1726 */1727#define for_each_zone_zonelist(zone, z, zlist, highidx) \1728 for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, NULL)1729 1730/* Whether the 'nodes' are all movable nodes */1731static inline bool movable_only_nodes(nodemask_t *nodes)1732{1733 struct zonelist *zonelist;1734 struct zoneref *z;1735 int nid;1736 1737 if (nodes_empty(*nodes))1738 return false;1739 1740 /*1741 * We can chose arbitrary node from the nodemask to get a1742 * zonelist as they are interlinked. We just need to find1743 * at least one zone that can satisfy kernel allocations.1744 */1745 nid = first_node(*nodes);1746 zonelist = &NODE_DATA(nid)->node_zonelists[ZONELIST_FALLBACK];1747 z = first_zones_zonelist(zonelist, ZONE_NORMAL, nodes);1748 return (!zonelist_zone(z)) ? true : false;1749}1750 1751 1752#ifdef CONFIG_SPARSEMEM1753#include <asm/sparsemem.h>1754#endif1755 1756#ifdef CONFIG_FLATMEM1757#define pfn_to_nid(pfn) (0)1758#endif1759 1760#ifdef CONFIG_SPARSEMEM1761 1762/*1763 * PA_SECTION_SHIFT physical address to/from section number1764 * PFN_SECTION_SHIFT pfn to/from section number1765 */1766#define PA_SECTION_SHIFT (SECTION_SIZE_BITS)1767#define PFN_SECTION_SHIFT (SECTION_SIZE_BITS - PAGE_SHIFT)1768 1769#define NR_MEM_SECTIONS (1UL << SECTIONS_SHIFT)1770 1771#define PAGES_PER_SECTION (1UL << PFN_SECTION_SHIFT)1772#define PAGE_SECTION_MASK (~(PAGES_PER_SECTION-1))1773 1774#define SECTION_BLOCKFLAGS_BITS \1775 ((1UL << (PFN_SECTION_SHIFT - pageblock_order)) * NR_PAGEBLOCK_BITS)1776 1777#if (MAX_PAGE_ORDER + PAGE_SHIFT) > SECTION_SIZE_BITS1778#error Allocator MAX_PAGE_ORDER exceeds SECTION_SIZE1779#endif1780 1781static inline unsigned long pfn_to_section_nr(unsigned long pfn)1782{1783 return pfn >> PFN_SECTION_SHIFT;1784}1785static inline unsigned long section_nr_to_pfn(unsigned long sec)1786{1787 return sec << PFN_SECTION_SHIFT;1788}1789 1790#define SECTION_ALIGN_UP(pfn) (((pfn) + PAGES_PER_SECTION - 1) & PAGE_SECTION_MASK)1791#define SECTION_ALIGN_DOWN(pfn) ((pfn) & PAGE_SECTION_MASK)1792 1793#define SUBSECTION_SHIFT 211794#define SUBSECTION_SIZE (1UL << SUBSECTION_SHIFT)1795 1796#define PFN_SUBSECTION_SHIFT (SUBSECTION_SHIFT - PAGE_SHIFT)1797#define PAGES_PER_SUBSECTION (1UL << PFN_SUBSECTION_SHIFT)1798#define PAGE_SUBSECTION_MASK (~(PAGES_PER_SUBSECTION-1))1799 1800#if SUBSECTION_SHIFT > SECTION_SIZE_BITS1801#error Subsection size exceeds section size1802#else1803#define SUBSECTIONS_PER_SECTION (1UL << (SECTION_SIZE_BITS - SUBSECTION_SHIFT))1804#endif1805 1806#define SUBSECTION_ALIGN_UP(pfn) ALIGN((pfn), PAGES_PER_SUBSECTION)1807#define SUBSECTION_ALIGN_DOWN(pfn) ((pfn) & PAGE_SUBSECTION_MASK)1808 1809struct mem_section_usage {1810 struct rcu_head rcu;1811#ifdef CONFIG_SPARSEMEM_VMEMMAP1812 DECLARE_BITMAP(subsection_map, SUBSECTIONS_PER_SECTION);1813#endif1814 /* See declaration of similar field in struct zone */1815 unsigned long pageblock_flags[0];1816};1817 1818void subsection_map_init(unsigned long pfn, unsigned long nr_pages);1819 1820struct page;1821struct page_ext;1822struct mem_section {1823 /*1824 * This is, logically, a pointer to an array of struct1825 * pages. However, it is stored with some other magic.1826 * (see sparse.c::sparse_init_one_section())1827 *1828 * Additionally during early boot we encode node id of1829 * the location of the section here to guide allocation.1830 * (see sparse.c::memory_present())1831 *1832 * Making it a UL at least makes someone do a cast1833 * before using it wrong.1834 */1835 unsigned long section_mem_map;1836 1837 struct mem_section_usage *usage;1838#ifdef CONFIG_PAGE_EXTENSION1839 /*1840 * If SPARSEMEM, pgdat doesn't have page_ext pointer. We use1841 * section. (see page_ext.h about this.)1842 */1843 struct page_ext *page_ext;1844 unsigned long pad;1845#endif1846 /*1847 * WARNING: mem_section must be a power-of-2 in size for the1848 * calculation and use of SECTION_ROOT_MASK to make sense.1849 */1850};1851 1852#ifdef CONFIG_SPARSEMEM_EXTREME1853#define SECTIONS_PER_ROOT (PAGE_SIZE / sizeof (struct mem_section))1854#else1855#define SECTIONS_PER_ROOT 11856#endif1857 1858#define SECTION_NR_TO_ROOT(sec) ((sec) / SECTIONS_PER_ROOT)1859#define NR_SECTION_ROOTS DIV_ROUND_UP(NR_MEM_SECTIONS, SECTIONS_PER_ROOT)1860#define SECTION_ROOT_MASK (SECTIONS_PER_ROOT - 1)1861 1862#ifdef CONFIG_SPARSEMEM_EXTREME1863extern struct mem_section **mem_section;1864#else1865extern struct mem_section mem_section[NR_SECTION_ROOTS][SECTIONS_PER_ROOT];1866#endif1867 1868static inline unsigned long *section_to_usemap(struct mem_section *ms)1869{1870 return ms->usage->pageblock_flags;1871}1872 1873static inline struct mem_section *__nr_to_section(unsigned long nr)1874{1875 unsigned long root = SECTION_NR_TO_ROOT(nr);1876 1877 if (unlikely(root >= NR_SECTION_ROOTS))1878 return NULL;1879 1880#ifdef CONFIG_SPARSEMEM_EXTREME1881 if (!mem_section || !mem_section[root])1882 return NULL;1883#endif1884 return &mem_section[root][nr & SECTION_ROOT_MASK];1885}1886extern size_t mem_section_usage_size(void);1887 1888/*1889 * We use the lower bits of the mem_map pointer to store1890 * a little bit of information. The pointer is calculated1891 * as mem_map - section_nr_to_pfn(pnum). The result is1892 * aligned to the minimum alignment of the two values:1893 * 1. All mem_map arrays are page-aligned.1894 * 2. section_nr_to_pfn() always clears PFN_SECTION_SHIFT1895 * lowest bits. PFN_SECTION_SHIFT is arch-specific1896 * (equal SECTION_SIZE_BITS - PAGE_SHIFT), and the1897 * worst combination is powerpc with 256k pages,1898 * which results in PFN_SECTION_SHIFT equal 6.1899 * To sum it up, at least 6 bits are available on all architectures.1900 * However, we can exceed 6 bits on some other architectures except1901 * powerpc (e.g. 15 bits are available on x86_64, 13 bits are available1902 * with the worst case of 64K pages on arm64) if we make sure the1903 * exceeded bit is not applicable to powerpc.1904 */1905enum {1906 SECTION_MARKED_PRESENT_BIT,1907 SECTION_HAS_MEM_MAP_BIT,1908 SECTION_IS_ONLINE_BIT,1909 SECTION_IS_EARLY_BIT,1910#ifdef CONFIG_ZONE_DEVICE1911 SECTION_TAINT_ZONE_DEVICE_BIT,1912#endif1913 SECTION_MAP_LAST_BIT,1914};1915 1916#define SECTION_MARKED_PRESENT BIT(SECTION_MARKED_PRESENT_BIT)1917#define SECTION_HAS_MEM_MAP BIT(SECTION_HAS_MEM_MAP_BIT)1918#define SECTION_IS_ONLINE BIT(SECTION_IS_ONLINE_BIT)1919#define SECTION_IS_EARLY BIT(SECTION_IS_EARLY_BIT)1920#ifdef CONFIG_ZONE_DEVICE1921#define SECTION_TAINT_ZONE_DEVICE BIT(SECTION_TAINT_ZONE_DEVICE_BIT)1922#endif1923#define SECTION_MAP_MASK (~(BIT(SECTION_MAP_LAST_BIT) - 1))1924#define SECTION_NID_SHIFT SECTION_MAP_LAST_BIT1925 1926static inline struct page *__section_mem_map_addr(struct mem_section *section)1927{1928 unsigned long map = section->section_mem_map;1929 map &= SECTION_MAP_MASK;1930 return (struct page *)map;1931}1932 1933static inline int present_section(struct mem_section *section)1934{1935 return (section && (section->section_mem_map & SECTION_MARKED_PRESENT));1936}1937 1938static inline int present_section_nr(unsigned long nr)1939{1940 return present_section(__nr_to_section(nr));1941}1942 1943static inline int valid_section(struct mem_section *section)1944{1945 return (section && (section->section_mem_map & SECTION_HAS_MEM_MAP));1946}1947 1948static inline int early_section(struct mem_section *section)1949{1950 return (section && (section->section_mem_map & SECTION_IS_EARLY));1951}1952 1953static inline int valid_section_nr(unsigned long nr)1954{1955 return valid_section(__nr_to_section(nr));1956}1957 1958static inline int online_section(struct mem_section *section)1959{1960 return (section && (section->section_mem_map & SECTION_IS_ONLINE));1961}1962 1963#ifdef CONFIG_ZONE_DEVICE1964static inline int online_device_section(struct mem_section *section)1965{1966 unsigned long flags = SECTION_IS_ONLINE | SECTION_TAINT_ZONE_DEVICE;1967 1968 return section && ((section->section_mem_map & flags) == flags);1969}1970#else1971static inline int online_device_section(struct mem_section *section)1972{1973 return 0;1974}1975#endif1976 1977static inline int online_section_nr(unsigned long nr)1978{1979 return online_section(__nr_to_section(nr));1980}1981 1982#ifdef CONFIG_MEMORY_HOTPLUG1983void online_mem_sections(unsigned long start_pfn, unsigned long end_pfn);1984void offline_mem_sections(unsigned long start_pfn, unsigned long end_pfn);1985#endif1986 1987static inline struct mem_section *__pfn_to_section(unsigned long pfn)1988{1989 return __nr_to_section(pfn_to_section_nr(pfn));1990}1991 1992extern unsigned long __highest_present_section_nr;1993 1994static inline int subsection_map_index(unsigned long pfn)1995{1996 return (pfn & ~(PAGE_SECTION_MASK)) / PAGES_PER_SUBSECTION;1997}1998 1999#ifdef CONFIG_SPARSEMEM_VMEMMAP2000static inline int pfn_section_valid(struct mem_section *ms, unsigned long pfn)2001{2002 int idx = subsection_map_index(pfn);2003 struct mem_section_usage *usage = READ_ONCE(ms->usage);2004 2005 return usage ? test_bit(idx, usage->subsection_map) : 0;2006}2007#else2008static inline int pfn_section_valid(struct mem_section *ms, unsigned long pfn)2009{2010 return 1;2011}2012#endif2013 2014#ifndef CONFIG_HAVE_ARCH_PFN_VALID2015/**2016 * pfn_valid - check if there is a valid memory map entry for a PFN2017 * @pfn: the page frame number to check2018 *2019 * Check if there is a valid memory map entry aka struct page for the @pfn.2020 * Note, that availability of the memory map entry does not imply that2021 * there is actual usable memory at that @pfn. The struct page may2022 * represent a hole or an unusable page frame.2023 *2024 * Return: 1 for PFNs that have memory map entries and 0 otherwise2025 */2026static inline int pfn_valid(unsigned long pfn)2027{2028 struct mem_section *ms;2029 int ret;2030 2031 /*2032 * Ensure the upper PAGE_SHIFT bits are clear in the2033 * pfn. Else it might lead to false positives when2034 * some of the upper bits are set, but the lower bits2035 * match a valid pfn.2036 */2037 if (PHYS_PFN(PFN_PHYS(pfn)) != pfn)2038 return 0;2039 2040 if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS)2041 return 0;2042 ms = __pfn_to_section(pfn);2043 rcu_read_lock_sched();2044 if (!valid_section(ms)) {2045 rcu_read_unlock_sched();2046 return 0;2047 }2048 /*2049 * Traditionally early sections always returned pfn_valid() for2050 * the entire section-sized span.2051 */2052 ret = early_section(ms) || pfn_section_valid(ms, pfn);2053 rcu_read_unlock_sched();2054 2055 return ret;2056}2057#endif2058 2059static inline int pfn_in_present_section(unsigned long pfn)2060{2061 if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS)2062 return 0;2063 return present_section(__pfn_to_section(pfn));2064}2065 2066static inline unsigned long next_present_section_nr(unsigned long section_nr)2067{2068 while (++section_nr <= __highest_present_section_nr) {2069 if (present_section_nr(section_nr))2070 return section_nr;2071 }2072 2073 return -1;2074}2075 2076/*2077 * These are _only_ used during initialisation, therefore they2078 * can use __initdata ... They could have names to indicate2079 * this restriction.2080 */2081#ifdef CONFIG_NUMA2082#define pfn_to_nid(pfn) \2083({ \2084 unsigned long __pfn_to_nid_pfn = (pfn); \2085 page_to_nid(pfn_to_page(__pfn_to_nid_pfn)); \2086})2087#else2088#define pfn_to_nid(pfn) (0)2089#endif2090 2091void sparse_init(void);2092#else2093#define sparse_init() do {} while (0)2094#define sparse_index_init(_sec, _nid) do {} while (0)2095#define pfn_in_present_section pfn_valid2096#define subsection_map_init(_pfn, _nr_pages) do {} while (0)2097#endif /* CONFIG_SPARSEMEM */2098 2099#endif /* !__GENERATING_BOUNDS.H */2100#endif /* !__ASSEMBLY__ */2101#endif /* _LINUX_MMZONE_H */2102