1 #ifndef _LINUX_MMZONE_H
2 #define _LINUX_MMZONE_H
5 #ifndef __GENERATING_BOUNDS_H
7 #include <linux/spinlock.h>
8 #include <linux/list.h>
9 #include <linux/wait.h>
10 #include <linux/bitops.h>
11 #include <linux/cache.h>
12 #include <linux/threads.h>
13 #include <linux/numa.h>
14 #include <linux/init.h>
15 #include <linux/seqlock.h>
16 #include <linux/nodemask.h>
17 #include <linux/pageblock-flags.h>
18 #include <linux/page-flags-layout.h>
19 #include <linux/atomic.h>
22 /* Free memory management - zoned buddy allocator. */
23 #ifndef CONFIG_FORCE_MAX_ZONEORDER
26 #define MAX_ORDER CONFIG_FORCE_MAX_ZONEORDER
28 #define MAX_ORDER_NR_PAGES (1 << (MAX_ORDER - 1))
31 * PAGE_ALLOC_COSTLY_ORDER is the order at which allocations are deemed
32 * costly to service. That is between allocation orders which should
33 * coalesce naturally under reasonable reclaim pressure and those which
36 #define PAGE_ALLOC_COSTLY_ORDER 3
42 MIGRATE_PCPTYPES, /* the number of types on the pcp lists */
43 MIGRATE_HIGHATOMIC = MIGRATE_PCPTYPES,
46 * MIGRATE_CMA migration type is designed to mimic the way
47 * ZONE_MOVABLE works. Only movable pages can be allocated
48 * from MIGRATE_CMA pageblocks and page allocator never
49 * implicitly change migration type of MIGRATE_CMA pageblock.
51 * The way to use it is to change migratetype of a range of
52 * pageblocks to MIGRATE_CMA which can be done by
53 * __free_pageblock_cma() function. What is important though
54 * is that a range of pageblocks must be aligned to
55 * MAX_ORDER_NR_PAGES should biggest page be bigger then
60 #ifdef CONFIG_MEMORY_ISOLATION
61 MIGRATE_ISOLATE, /* can't allocate from here */
66 /* In mm/page_alloc.c; keep in sync also with show_migration_types() there */
67 extern char * const migratetype_names[MIGRATE_TYPES];
70 # define is_migrate_cma(migratetype) unlikely((migratetype) == MIGRATE_CMA)
72 # define is_migrate_cma(migratetype) false
75 #define for_each_migratetype_order(order, type) \
76 for (order = 0; order < MAX_ORDER; order++) \
77 for (type = 0; type < MIGRATE_TYPES; type++)
79 extern int page_group_by_mobility_disabled;
81 #define NR_MIGRATETYPE_BITS (PB_migrate_end - PB_migrate + 1)
82 #define MIGRATETYPE_MASK ((1UL << NR_MIGRATETYPE_BITS) - 1)
84 #define get_pageblock_migratetype(page) \
85 get_pfnblock_flags_mask(page, page_to_pfn(page), \
86 PB_migrate_end, MIGRATETYPE_MASK)
89 struct list_head free_list[MIGRATE_TYPES];
90 unsigned long nr_free;
96 * zone->lock and the zone lru_lock are two of the hottest locks in the kernel.
97 * So add a wild amount of padding here to ensure that they fall into separate
98 * cachelines. There are very few zone structures in the machine, so space
99 * consumption is not a concern here.
101 #if defined(CONFIG_SMP)
102 struct zone_padding {
104 } ____cacheline_internodealigned_in_smp;
105 #define ZONE_PADDING(name) struct zone_padding name;
107 #define ZONE_PADDING(name)
110 enum zone_stat_item {
111 /* First 128 byte cacheline (assuming 64 bit words) */
114 NR_ZONE_LRU_BASE, /* Used only for compaction and reclaim retry */
115 NR_ZONE_LRU_ANON = NR_ZONE_LRU_BASE,
117 NR_MLOCK, /* mlock()ed pages found and moved off LRU */
118 NR_ANON_PAGES, /* Mapped anonymous pages */
119 NR_FILE_MAPPED, /* pagecache pages mapped into pagetables.
120 only modified from process context */
125 NR_SLAB_UNRECLAIMABLE,
126 NR_PAGETABLE, /* used for pagetables */
128 /* Second 128 byte cacheline */
129 NR_UNSTABLE_NFS, /* NFS unstable pages */
132 NR_VMSCAN_IMMEDIATE, /* Prioritise for reclaim when writeback ends */
133 NR_WRITEBACK_TEMP, /* Writeback using temporary buffers */
134 NR_SHMEM, /* shmem pages (included tmpfs/GEM pages) */
135 NR_DIRTIED, /* page dirtyings since bootup */
136 NR_WRITTEN, /* page writings since bootup */
137 #if IS_ENABLED(CONFIG_ZSMALLOC)
138 NR_ZSPAGES, /* allocated in zsmalloc */
141 NUMA_HIT, /* allocated in intended node */
142 NUMA_MISS, /* allocated in non intended node */
143 NUMA_FOREIGN, /* was intended here, hit elsewhere */
144 NUMA_INTERLEAVE_HIT, /* interleaver preferred this zone */
145 NUMA_LOCAL, /* allocation from local node */
146 NUMA_OTHER, /* allocation from other node */
152 NR_VM_ZONE_STAT_ITEMS };
154 enum node_stat_item {
156 NR_INACTIVE_ANON = NR_LRU_BASE, /* must match order of LRU_[IN]ACTIVE */
157 NR_ACTIVE_ANON, /* " " " " " */
158 NR_INACTIVE_FILE, /* " " " " " */
159 NR_ACTIVE_FILE, /* " " " " " */
160 NR_UNEVICTABLE, /* " " " " " */
161 NR_ISOLATED_ANON, /* Temporary isolated pages from anon lru */
162 NR_ISOLATED_FILE, /* Temporary isolated pages from file lru */
163 NR_PAGES_SCANNED, /* pages scanned since last reclaim */
166 WORKINGSET_NODERECLAIM,
167 NR_VM_NODE_STAT_ITEMS
171 * We do arithmetic on the LRU lists in various places in the code,
172 * so it is important to keep the active lists LRU_ACTIVE higher in
173 * the array than the corresponding inactive lists, and to keep
174 * the *_FILE lists LRU_FILE higher than the corresponding _ANON lists.
176 * This has to be kept in sync with the statistics in zone_stat_item
177 * above and the descriptions in vmstat_text in mm/vmstat.c
184 LRU_INACTIVE_ANON = LRU_BASE,
185 LRU_ACTIVE_ANON = LRU_BASE + LRU_ACTIVE,
186 LRU_INACTIVE_FILE = LRU_BASE + LRU_FILE,
187 LRU_ACTIVE_FILE = LRU_BASE + LRU_FILE + LRU_ACTIVE,
192 #define for_each_lru(lru) for (lru = 0; lru < NR_LRU_LISTS; lru++)
194 #define for_each_evictable_lru(lru) for (lru = 0; lru <= LRU_ACTIVE_FILE; lru++)
196 static inline int is_file_lru(enum lru_list lru)
198 return (lru == LRU_INACTIVE_FILE || lru == LRU_ACTIVE_FILE);
201 static inline int is_active_lru(enum lru_list lru)
203 return (lru == LRU_ACTIVE_ANON || lru == LRU_ACTIVE_FILE);
206 struct zone_reclaim_stat {
208 * The pageout code in vmscan.c keeps track of how many of the
209 * mem/swap backed and file backed pages are referenced.
210 * The higher the rotated/scanned ratio, the more valuable
213 * The anon LRU stats live in [0], file LRU stats in [1]
215 unsigned long recent_rotated[2];
216 unsigned long recent_scanned[2];
220 struct list_head lists[NR_LRU_LISTS];
221 struct zone_reclaim_stat reclaim_stat;
222 /* Evictions & activations on the inactive file list */
223 atomic_long_t inactive_age;
225 struct pglist_data *pgdat;
229 /* Mask used at gathering information at once (see memcontrol.c) */
230 #define LRU_ALL_FILE (BIT(LRU_INACTIVE_FILE) | BIT(LRU_ACTIVE_FILE))
231 #define LRU_ALL_ANON (BIT(LRU_INACTIVE_ANON) | BIT(LRU_ACTIVE_ANON))
232 #define LRU_ALL ((1 << NR_LRU_LISTS) - 1)
234 /* Isolate clean file */
235 #define ISOLATE_CLEAN ((__force isolate_mode_t)0x1)
236 /* Isolate unmapped file */
237 #define ISOLATE_UNMAPPED ((__force isolate_mode_t)0x2)
238 /* Isolate for asynchronous migration */
239 #define ISOLATE_ASYNC_MIGRATE ((__force isolate_mode_t)0x4)
240 /* Isolate unevictable pages */
241 #define ISOLATE_UNEVICTABLE ((__force isolate_mode_t)0x8)
243 /* LRU Isolation modes. */
244 typedef unsigned __bitwise__ isolate_mode_t;
246 enum zone_watermarks {
253 #define min_wmark_pages(z) (z->watermark[WMARK_MIN])
254 #define low_wmark_pages(z) (z->watermark[WMARK_LOW])
255 #define high_wmark_pages(z) (z->watermark[WMARK_HIGH])
257 struct per_cpu_pages {
258 int count; /* number of pages in the list */
259 int high; /* high watermark, emptying needed */
260 int batch; /* chunk size for buddy add/remove */
262 /* Lists of pages, one per migrate type stored on the pcp-lists */
263 struct list_head lists[MIGRATE_PCPTYPES];
266 struct per_cpu_pageset {
267 struct per_cpu_pages pcp;
273 s8 vm_stat_diff[NR_VM_ZONE_STAT_ITEMS];
277 struct per_cpu_nodestat {
279 s8 vm_node_stat_diff[NR_VM_NODE_STAT_ITEMS];
282 #endif /* !__GENERATING_BOUNDS.H */
285 #ifdef CONFIG_ZONE_DMA
287 * ZONE_DMA is used when there are devices that are not able
288 * to do DMA to all of addressable memory (ZONE_NORMAL). Then we
289 * carve out the portion of memory that is needed for these devices.
290 * The range is arch specific.
295 * ---------------------------
296 * parisc, ia64, sparc <4G
299 * alpha Unlimited or 0-16MB.
301 * i386, x86_64 and multiple other arches
306 #ifdef CONFIG_ZONE_DMA32
308 * x86_64 needs two ZONE_DMAs because it supports devices that are
309 * only able to do DMA to the lower 16M but also 32 bit devices that
310 * can only do DMA areas below 4G.
315 * Normal addressable memory is in ZONE_NORMAL. DMA operations can be
316 * performed on pages in ZONE_NORMAL if the DMA devices support
317 * transfers to all addressable memory.
320 #ifdef CONFIG_HIGHMEM
322 * A memory area that is only addressable by the kernel through
323 * mapping portions into its own address space. This is for example
324 * used by i386 to allow the kernel to address the memory beyond
325 * 900MB. The kernel will set up special mappings (page
326 * table entries on i386) for each page that the kernel needs to
332 #ifdef CONFIG_ZONE_DEVICE
339 #ifndef __GENERATING_BOUNDS_H
342 /* Read-mostly fields */
344 /* zone watermarks, access with *_wmark_pages(zone) macros */
345 unsigned long watermark[NR_WMARK];
347 unsigned long nr_reserved_highatomic;
350 * We don't know if the memory that we're going to allocate will be
351 * freeable or/and it will be released eventually, so to avoid totally
352 * wasting several GB of ram we must reserve some of the lower zone
353 * memory (otherwise we risk to run OOM on the lower zones despite
354 * there being tons of freeable ram on the higher zones). This array is
355 * recalculated at runtime if the sysctl_lowmem_reserve_ratio sysctl
358 long lowmem_reserve[MAX_NR_ZONES];
363 struct pglist_data *zone_pgdat;
364 struct per_cpu_pageset __percpu *pageset;
367 * This is a per-zone reserve of pages that are not available
368 * to userspace allocations.
370 unsigned long totalreserve_pages;
372 #ifndef CONFIG_SPARSEMEM
374 * Flags for a pageblock_nr_pages block. See pageblock-flags.h.
375 * In SPARSEMEM, this map is stored in struct mem_section
377 unsigned long *pageblock_flags;
378 #endif /* CONFIG_SPARSEMEM */
382 * zone reclaim becomes active if more unmapped pages exist.
384 unsigned long min_unmapped_pages;
385 unsigned long min_slab_pages;
386 #endif /* CONFIG_NUMA */
388 /* zone_start_pfn == zone_start_paddr >> PAGE_SHIFT */
389 unsigned long zone_start_pfn;
392 * spanned_pages is the total pages spanned by the zone, including
393 * holes, which is calculated as:
394 * spanned_pages = zone_end_pfn - zone_start_pfn;
396 * present_pages is physical pages existing within the zone, which
398 * present_pages = spanned_pages - absent_pages(pages in holes);
400 * managed_pages is present pages managed by the buddy system, which
401 * is calculated as (reserved_pages includes pages allocated by the
402 * bootmem allocator):
403 * managed_pages = present_pages - reserved_pages;
405 * So present_pages may be used by memory hotplug or memory power
406 * management logic to figure out unmanaged pages by checking
407 * (present_pages - managed_pages). And managed_pages should be used
408 * by page allocator and vm scanner to calculate all kinds of watermarks
413 * zone_start_pfn and spanned_pages are protected by span_seqlock.
414 * It is a seqlock because it has to be read outside of zone->lock,
415 * and it is done in the main allocator path. But, it is written
416 * quite infrequently.
418 * The span_seq lock is declared along with zone->lock because it is
419 * frequently read in proximity to zone->lock. It's good to
420 * give them a chance of being in the same cacheline.
422 * Write access to present_pages at runtime should be protected by
423 * mem_hotplug_begin/end(). Any reader who can't tolerant drift of
424 * present_pages should get_online_mems() to get a stable value.
426 * Read access to managed_pages should be safe because it's unsigned
427 * long. Write access to zone->managed_pages and totalram_pages are
428 * protected by managed_page_count_lock at runtime. Idealy only
429 * adjust_managed_page_count() should be used instead of directly
430 * touching zone->managed_pages and totalram_pages.
432 unsigned long managed_pages;
433 unsigned long spanned_pages;
434 unsigned long present_pages;
438 #ifdef CONFIG_MEMORY_ISOLATION
440 * Number of isolated pageblock. It is used to solve incorrect
441 * freepage counting problem due to racy retrieving migratetype
442 * of pageblock. Protected by zone->lock.
444 unsigned long nr_isolate_pageblock;
447 #ifdef CONFIG_MEMORY_HOTPLUG
448 /* see spanned/present_pages for more description */
449 seqlock_t span_seqlock;
453 * wait_table -- the array holding the hash table
454 * wait_table_hash_nr_entries -- the size of the hash table array
455 * wait_table_bits -- wait_table_size == (1 << wait_table_bits)
457 * The purpose of all these is to keep track of the people
458 * waiting for a page to become available and make them
459 * runnable again when possible. The trouble is that this
460 * consumes a lot of space, especially when so few things
461 * wait on pages at a given time. So instead of using
462 * per-page waitqueues, we use a waitqueue hash table.
464 * The bucket discipline is to sleep on the same queue when
465 * colliding and wake all in that wait queue when removing.
466 * When something wakes, it must check to be sure its page is
467 * truly available, a la thundering herd. The cost of a
468 * collision is great, but given the expected load of the
469 * table, they should be so rare as to be outweighed by the
470 * benefits from the saved space.
472 * __wait_on_page_locked() and unlock_page() in mm/filemap.c, are the
473 * primary users of these fields, and in mm/page_alloc.c
474 * free_area_init_core() performs the initialization of them.
476 wait_queue_head_t *wait_table;
477 unsigned long wait_table_hash_nr_entries;
478 unsigned long wait_table_bits;
480 /* Write-intensive fields used from the page allocator */
483 /* free areas of different sizes */
484 struct free_area free_area[MAX_ORDER];
486 /* zone flags, see below */
489 /* Primarily protects free_area */
492 /* Write-intensive fields used by compaction and vmstats. */
496 * When free pages are below this point, additional steps are taken
497 * when reading the number of free pages to avoid per-cpu counter
498 * drift allowing watermarks to be breached
500 unsigned long percpu_drift_mark;
502 #if defined CONFIG_COMPACTION || defined CONFIG_CMA
503 /* pfn where compaction free scanner should start */
504 unsigned long compact_cached_free_pfn;
505 /* pfn where async and sync compaction migration scanner should start */
506 unsigned long compact_cached_migrate_pfn[2];
509 #ifdef CONFIG_COMPACTION
511 * On compaction failure, 1<<compact_defer_shift compactions
512 * are skipped before trying again. The number attempted since
513 * last failure is tracked with compact_considered.
515 unsigned int compact_considered;
516 unsigned int compact_defer_shift;
517 int compact_order_failed;
520 #if defined CONFIG_COMPACTION || defined CONFIG_CMA
521 /* Set to true when the PG_migrate_skip bits should be cleared */
522 bool compact_blockskip_flush;
528 /* Zone statistics */
529 atomic_long_t vm_stat[NR_VM_ZONE_STAT_ITEMS];
530 } ____cacheline_internodealigned_in_smp;
533 ZONE_RECLAIM_LOCKED, /* prevents concurrent reclaim */
534 ZONE_FAIR_DEPLETED, /* fair zone policy batch depleted */
538 PGDAT_CONGESTED, /* pgdat has many dirty pages backed by
541 PGDAT_DIRTY, /* reclaim scanning has recently found
542 * many dirty file pages at the tail
545 PGDAT_WRITEBACK, /* reclaim scanning has recently found
546 * many pages under writeback
550 static inline unsigned long zone_end_pfn(const struct zone *zone)
552 return zone->zone_start_pfn + zone->spanned_pages;
555 static inline bool zone_spans_pfn(const struct zone *zone, unsigned long pfn)
557 return zone->zone_start_pfn <= pfn && pfn < zone_end_pfn(zone);
560 static inline bool zone_is_initialized(struct zone *zone)
562 return !!zone->wait_table;
565 static inline bool zone_is_empty(struct zone *zone)
567 return zone->spanned_pages == 0;
571 * The "priority" of VM scanning is how much of the queues we will scan in one
572 * go. A value of 12 for DEF_PRIORITY implies that we will scan 1/4096th of the
573 * queues ("queue_length >> 12") during an aging round.
575 #define DEF_PRIORITY 12
577 /* Maximum number of zones on a zonelist */
578 #define MAX_ZONES_PER_ZONELIST (MAX_NUMNODES * MAX_NR_ZONES)
581 ZONELIST_FALLBACK, /* zonelist with fallback */
584 * The NUMA zonelists are doubled because we need zonelists that
585 * restrict the allocations to a single node for __GFP_THISNODE.
587 ZONELIST_NOFALLBACK, /* zonelist without fallback (__GFP_THISNODE) */
593 * This struct contains information about a zone in a zonelist. It is stored
594 * here to avoid dereferences into large structures and lookups of tables
597 struct zone *zone; /* Pointer to actual zone */
598 int zone_idx; /* zone_idx(zoneref->zone) */
602 * One allocation request operates on a zonelist. A zonelist
603 * is a list of zones, the first one is the 'goal' of the
604 * allocation, the other zones are fallback zones, in decreasing
607 * To speed the reading of the zonelist, the zonerefs contain the zone index
608 * of the entry being read. Helper functions to access information given
609 * a struct zoneref are
611 * zonelist_zone() - Return the struct zone * for an entry in _zonerefs
612 * zonelist_zone_idx() - Return the index of the zone for an entry
613 * zonelist_node_idx() - Return the index of the node for an entry
616 struct zoneref _zonerefs[MAX_ZONES_PER_ZONELIST + 1];
619 #ifndef CONFIG_DISCONTIGMEM
620 /* The array of struct pages - for discontigmem use pgdat->lmem_map */
621 extern struct page *mem_map;
625 * The pg_data_t structure is used in machines with CONFIG_DISCONTIGMEM
626 * (mostly NUMA machines?) to denote a higher-level memory zone than the
629 * On NUMA machines, each NUMA node would have a pg_data_t to describe
630 * it's memory layout.
632 * Memory statistics and page replacement data structures are maintained on a
636 typedef struct pglist_data {
637 struct zone node_zones[MAX_NR_ZONES];
638 struct zonelist node_zonelists[MAX_ZONELISTS];
640 #ifdef CONFIG_FLAT_NODE_MEM_MAP /* means !SPARSEMEM */
641 struct page *node_mem_map;
642 #ifdef CONFIG_PAGE_EXTENSION
643 struct page_ext *node_page_ext;
646 #ifndef CONFIG_NO_BOOTMEM
647 struct bootmem_data *bdata;
649 #ifdef CONFIG_MEMORY_HOTPLUG
651 * Must be held any time you expect node_start_pfn, node_present_pages
652 * or node_spanned_pages stay constant. Holding this will also
653 * guarantee that any pfn_valid() stays that way.
655 * pgdat_resize_lock() and pgdat_resize_unlock() are provided to
656 * manipulate node_size_lock without checking for CONFIG_MEMORY_HOTPLUG.
658 * Nests above zone->lock and zone->span_seqlock
660 spinlock_t node_size_lock;
662 unsigned long node_start_pfn;
663 unsigned long node_present_pages; /* total number of physical pages */
664 unsigned long node_spanned_pages; /* total size of physical page
665 range, including holes */
667 wait_queue_head_t kswapd_wait;
668 wait_queue_head_t pfmemalloc_wait;
669 struct task_struct *kswapd; /* Protected by
670 mem_hotplug_begin/end() */
672 enum zone_type kswapd_classzone_idx;
674 #ifdef CONFIG_COMPACTION
675 int kcompactd_max_order;
676 enum zone_type kcompactd_classzone_idx;
677 wait_queue_head_t kcompactd_wait;
678 struct task_struct *kcompactd;
680 #ifdef CONFIG_NUMA_BALANCING
681 /* Lock serializing the migrate rate limiting window */
682 spinlock_t numabalancing_migrate_lock;
684 /* Rate limiting time interval */
685 unsigned long numabalancing_migrate_next_window;
687 /* Number of pages migrated during the rate limiting time interval */
688 unsigned long numabalancing_migrate_nr_pages;
690 /* Write-intensive fields used by page reclaim */
694 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
696 * If memory initialisation on large machines is deferred then this
697 * is the first PFN that needs to be initialised.
699 unsigned long first_deferred_pfn;
700 #endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */
702 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
703 spinlock_t split_queue_lock;
704 struct list_head split_queue;
705 unsigned long split_queue_len;
708 /* Fields commonly accessed by the page reclaim scanner */
709 struct lruvec lruvec;
712 * The target ratio of ACTIVE_ANON to INACTIVE_ANON pages on
713 * this node's LRU. Maintained by the pageout code.
715 unsigned int inactive_ratio;
721 /* Per-node vmstats */
722 struct per_cpu_nodestat __percpu *per_cpu_nodestats;
723 atomic_long_t vm_stat[NR_VM_NODE_STAT_ITEMS];
726 #define node_present_pages(nid) (NODE_DATA(nid)->node_present_pages)
727 #define node_spanned_pages(nid) (NODE_DATA(nid)->node_spanned_pages)
728 #ifdef CONFIG_FLAT_NODE_MEM_MAP
729 #define pgdat_page_nr(pgdat, pagenr) ((pgdat)->node_mem_map + (pagenr))
731 #define pgdat_page_nr(pgdat, pagenr) pfn_to_page((pgdat)->node_start_pfn + (pagenr))
733 #define nid_page_nr(nid, pagenr) pgdat_page_nr(NODE_DATA(nid),(pagenr))
735 #define node_start_pfn(nid) (NODE_DATA(nid)->node_start_pfn)
736 #define node_end_pfn(nid) pgdat_end_pfn(NODE_DATA(nid))
737 static inline spinlock_t *zone_lru_lock(struct zone *zone)
739 return &zone->zone_pgdat->lru_lock;
742 static inline struct lruvec *node_lruvec(struct pglist_data *pgdat)
744 return &pgdat->lruvec;
747 static inline unsigned long pgdat_end_pfn(pg_data_t *pgdat)
749 return pgdat->node_start_pfn + pgdat->node_spanned_pages;
752 static inline bool pgdat_is_empty(pg_data_t *pgdat)
754 return !pgdat->node_start_pfn && !pgdat->node_spanned_pages;
757 static inline int zone_id(const struct zone *zone)
759 struct pglist_data *pgdat = zone->zone_pgdat;
761 return zone - pgdat->node_zones;
764 #ifdef CONFIG_ZONE_DEVICE
765 static inline bool is_dev_zone(const struct zone *zone)
767 return zone_id(zone) == ZONE_DEVICE;
770 static inline bool is_dev_zone(const struct zone *zone)
776 #include <linux/memory_hotplug.h>
778 extern struct mutex zonelists_mutex;
779 void build_all_zonelists(pg_data_t *pgdat, struct zone *zone);
780 void wakeup_kswapd(struct zone *zone, int order, enum zone_type classzone_idx);
781 bool __zone_watermark_ok(struct zone *z, unsigned int order, unsigned long mark,
782 int classzone_idx, unsigned int alloc_flags,
784 bool zone_watermark_ok(struct zone *z, unsigned int order,
785 unsigned long mark, int classzone_idx,
786 unsigned int alloc_flags);
787 bool zone_watermark_ok_safe(struct zone *z, unsigned int order,
788 unsigned long mark, int classzone_idx);
789 enum memmap_context {
793 extern int init_currently_empty_zone(struct zone *zone, unsigned long start_pfn,
796 extern void lruvec_init(struct lruvec *lruvec);
798 static inline struct pglist_data *lruvec_pgdat(struct lruvec *lruvec)
801 return lruvec->pgdat;
803 return container_of(lruvec, struct pglist_data, lruvec);
807 extern unsigned long lruvec_lru_size(struct lruvec *lruvec, enum lru_list lru);
809 #ifdef CONFIG_HAVE_MEMORY_PRESENT
810 void memory_present(int nid, unsigned long start, unsigned long end);
812 static inline void memory_present(int nid, unsigned long start, unsigned long end) {}
815 #ifdef CONFIG_HAVE_MEMORYLESS_NODES
816 int local_memory_node(int node_id);
818 static inline int local_memory_node(int node_id) { return node_id; };
821 #ifdef CONFIG_NEED_NODE_MEMMAP_SIZE
822 unsigned long __init node_memmap_size_bytes(int, unsigned long, unsigned long);
826 * zone_idx() returns 0 for the ZONE_DMA zone, 1 for the ZONE_NORMAL zone, etc.
828 #define zone_idx(zone) ((zone) - (zone)->zone_pgdat->node_zones)
830 static inline int populated_zone(struct zone *zone)
832 return (!!zone->present_pages);
835 extern int movable_zone;
837 #ifdef CONFIG_HIGHMEM
838 static inline int zone_movable_is_highmem(void)
840 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
841 return movable_zone == ZONE_HIGHMEM;
843 return (ZONE_MOVABLE - 1) == ZONE_HIGHMEM;
848 static inline int is_highmem_idx(enum zone_type idx)
850 #ifdef CONFIG_HIGHMEM
851 return (idx == ZONE_HIGHMEM ||
852 (idx == ZONE_MOVABLE && zone_movable_is_highmem()));
859 * is_highmem - helper function to quickly check if a struct zone is a
860 * highmem zone or not. This is an attempt to keep references
861 * to ZONE_{DMA/NORMAL/HIGHMEM/etc} in general code to a minimum.
862 * @zone - pointer to struct zone variable
864 static inline int is_highmem(struct zone *zone)
866 #ifdef CONFIG_HIGHMEM
867 return is_highmem_idx(zone_idx(zone));
873 /* These two functions are used to setup the per zone pages min values */
875 int min_free_kbytes_sysctl_handler(struct ctl_table *, int,
876 void __user *, size_t *, loff_t *);
877 int watermark_scale_factor_sysctl_handler(struct ctl_table *, int,
878 void __user *, size_t *, loff_t *);
879 extern int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES-1];
880 int lowmem_reserve_ratio_sysctl_handler(struct ctl_table *, int,
881 void __user *, size_t *, loff_t *);
882 int percpu_pagelist_fraction_sysctl_handler(struct ctl_table *, int,
883 void __user *, size_t *, loff_t *);
884 int sysctl_min_unmapped_ratio_sysctl_handler(struct ctl_table *, int,
885 void __user *, size_t *, loff_t *);
886 int sysctl_min_slab_ratio_sysctl_handler(struct ctl_table *, int,
887 void __user *, size_t *, loff_t *);
889 extern int numa_zonelist_order_handler(struct ctl_table *, int,
890 void __user *, size_t *, loff_t *);
891 extern char numa_zonelist_order[];
892 #define NUMA_ZONELIST_ORDER_LEN 16 /* string buffer size */
894 #ifndef CONFIG_NEED_MULTIPLE_NODES
896 extern struct pglist_data contig_page_data;
897 #define NODE_DATA(nid) (&contig_page_data)
898 #define NODE_MEM_MAP(nid) mem_map
900 #else /* CONFIG_NEED_MULTIPLE_NODES */
902 #include <asm/mmzone.h>
904 #endif /* !CONFIG_NEED_MULTIPLE_NODES */
906 extern struct pglist_data *first_online_pgdat(void);
907 extern struct pglist_data *next_online_pgdat(struct pglist_data *pgdat);
908 extern struct zone *next_zone(struct zone *zone);
911 * for_each_online_pgdat - helper macro to iterate over all online nodes
912 * @pgdat - pointer to a pg_data_t variable
914 #define for_each_online_pgdat(pgdat) \
915 for (pgdat = first_online_pgdat(); \
917 pgdat = next_online_pgdat(pgdat))
919 * for_each_zone - helper macro to iterate over all memory zones
920 * @zone - pointer to struct zone variable
922 * The user only needs to declare the zone variable, for_each_zone
925 #define for_each_zone(zone) \
926 for (zone = (first_online_pgdat())->node_zones; \
928 zone = next_zone(zone))
930 #define for_each_populated_zone(zone) \
931 for (zone = (first_online_pgdat())->node_zones; \
933 zone = next_zone(zone)) \
934 if (!populated_zone(zone)) \
938 static inline struct zone *zonelist_zone(struct zoneref *zoneref)
940 return zoneref->zone;
943 static inline int zonelist_zone_idx(struct zoneref *zoneref)
945 return zoneref->zone_idx;
948 static inline int zonelist_node_idx(struct zoneref *zoneref)
951 /* zone_to_nid not available in this context */
952 return zoneref->zone->node;
955 #endif /* CONFIG_NUMA */
958 struct zoneref *__next_zones_zonelist(struct zoneref *z,
959 enum zone_type highest_zoneidx,
963 * 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 point
964 * @z - The cursor used as a starting point for the search
965 * @highest_zoneidx - The zone index of the highest zone to return
966 * @nodes - An optional nodemask to filter the zonelist with
968 * This function returns the next zone at or below a given zone index that is
969 * within the allowed nodemask using a cursor as the starting point for the
970 * search. The zoneref returned is a cursor that represents the current zone
971 * being examined. It should be advanced by one before calling
972 * next_zones_zonelist again.
974 static __always_inline struct zoneref *next_zones_zonelist(struct zoneref *z,
975 enum zone_type highest_zoneidx,
978 if (likely(!nodes && zonelist_zone_idx(z) <= highest_zoneidx))
980 return __next_zones_zonelist(z, highest_zoneidx, nodes);
984 * first_zones_zonelist - Returns the first zone at or below highest_zoneidx within the allowed nodemask in a zonelist
985 * @zonelist - The zonelist to search for a suitable zone
986 * @highest_zoneidx - The zone index of the highest zone to return
987 * @nodes - An optional nodemask to filter the zonelist with
988 * @zone - The first suitable zone found is returned via this parameter
990 * This function returns the first zone at or below a given zone index that is
991 * within the allowed nodemask. The zoneref returned is a cursor that can be
992 * used to iterate the zonelist with next_zones_zonelist by advancing it by
993 * one before calling.
995 static inline struct zoneref *first_zones_zonelist(struct zonelist *zonelist,
996 enum zone_type highest_zoneidx,
999 return next_zones_zonelist(zonelist->_zonerefs,
1000 highest_zoneidx, nodes);
1004 * 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 nodemask
1005 * @zone - The current zone in the iterator
1006 * @z - The current pointer within zonelist->zones being iterated
1007 * @zlist - The zonelist being iterated
1008 * @highidx - The zone index of the highest zone to return
1009 * @nodemask - Nodemask allowed by the allocator
1011 * This iterator iterates though all zones at or below a given zone index and
1012 * within a given nodemask
1014 #define for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, nodemask) \
1015 for (z = first_zones_zonelist(zlist, highidx, nodemask), zone = zonelist_zone(z); \
1017 z = next_zones_zonelist(++z, highidx, nodemask), \
1018 zone = zonelist_zone(z))
1020 #define for_next_zone_zonelist_nodemask(zone, z, zlist, highidx, nodemask) \
1021 for (zone = z->zone; \
1023 z = next_zones_zonelist(++z, highidx, nodemask), \
1024 zone = zonelist_zone(z))
1028 * for_each_zone_zonelist - helper macro to iterate over valid zones in a zonelist at or below a given zone index
1029 * @zone - The current zone in the iterator
1030 * @z - The current pointer within zonelist->zones being iterated
1031 * @zlist - The zonelist being iterated
1032 * @highidx - The zone index of the highest zone to return
1034 * This iterator iterates though all zones at or below a given zone index.
1036 #define for_each_zone_zonelist(zone, z, zlist, highidx) \
1037 for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, NULL)
1039 #ifdef CONFIG_SPARSEMEM
1040 #include <asm/sparsemem.h>
1043 #if !defined(CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID) && \
1044 !defined(CONFIG_HAVE_MEMBLOCK_NODE_MAP)
1045 static inline unsigned long early_pfn_to_nid(unsigned long pfn)
1051 #ifdef CONFIG_FLATMEM
1052 #define pfn_to_nid(pfn) (0)
1055 #ifdef CONFIG_SPARSEMEM
1058 * SECTION_SHIFT #bits space required to store a section #
1060 * PA_SECTION_SHIFT physical address to/from section number
1061 * PFN_SECTION_SHIFT pfn to/from section number
1063 #define PA_SECTION_SHIFT (SECTION_SIZE_BITS)
1064 #define PFN_SECTION_SHIFT (SECTION_SIZE_BITS - PAGE_SHIFT)
1066 #define NR_MEM_SECTIONS (1UL << SECTIONS_SHIFT)
1068 #define PAGES_PER_SECTION (1UL << PFN_SECTION_SHIFT)
1069 #define PAGE_SECTION_MASK (~(PAGES_PER_SECTION-1))
1071 #define SECTION_BLOCKFLAGS_BITS \
1072 ((1UL << (PFN_SECTION_SHIFT - pageblock_order)) * NR_PAGEBLOCK_BITS)
1074 #if (MAX_ORDER - 1 + PAGE_SHIFT) > SECTION_SIZE_BITS
1075 #error Allocator MAX_ORDER exceeds SECTION_SIZE
1078 #define pfn_to_section_nr(pfn) ((pfn) >> PFN_SECTION_SHIFT)
1079 #define section_nr_to_pfn(sec) ((sec) << PFN_SECTION_SHIFT)
1081 #define SECTION_ALIGN_UP(pfn) (((pfn) + PAGES_PER_SECTION - 1) & PAGE_SECTION_MASK)
1082 #define SECTION_ALIGN_DOWN(pfn) ((pfn) & PAGE_SECTION_MASK)
1086 struct mem_section {
1088 * This is, logically, a pointer to an array of struct
1089 * pages. However, it is stored with some other magic.
1090 * (see sparse.c::sparse_init_one_section())
1092 * Additionally during early boot we encode node id of
1093 * the location of the section here to guide allocation.
1094 * (see sparse.c::memory_present())
1096 * Making it a UL at least makes someone do a cast
1097 * before using it wrong.
1099 unsigned long section_mem_map;
1101 /* See declaration of similar field in struct zone */
1102 unsigned long *pageblock_flags;
1103 #ifdef CONFIG_PAGE_EXTENSION
1105 * If SPARSEMEM, pgdat doesn't have page_ext pointer. We use
1106 * section. (see page_ext.h about this.)
1108 struct page_ext *page_ext;
1112 * WARNING: mem_section must be a power-of-2 in size for the
1113 * calculation and use of SECTION_ROOT_MASK to make sense.
1117 #ifdef CONFIG_SPARSEMEM_EXTREME
1118 #define SECTIONS_PER_ROOT (PAGE_SIZE / sizeof (struct mem_section))
1120 #define SECTIONS_PER_ROOT 1
1123 #define SECTION_NR_TO_ROOT(sec) ((sec) / SECTIONS_PER_ROOT)
1124 #define NR_SECTION_ROOTS DIV_ROUND_UP(NR_MEM_SECTIONS, SECTIONS_PER_ROOT)
1125 #define SECTION_ROOT_MASK (SECTIONS_PER_ROOT - 1)
1127 #ifdef CONFIG_SPARSEMEM_EXTREME
1128 extern struct mem_section *mem_section[NR_SECTION_ROOTS];
1130 extern struct mem_section mem_section[NR_SECTION_ROOTS][SECTIONS_PER_ROOT];
1133 static inline struct mem_section *__nr_to_section(unsigned long nr)
1135 if (!mem_section[SECTION_NR_TO_ROOT(nr)])
1137 return &mem_section[SECTION_NR_TO_ROOT(nr)][nr & SECTION_ROOT_MASK];
1139 extern int __section_nr(struct mem_section* ms);
1140 extern unsigned long usemap_size(void);
1143 * We use the lower bits of the mem_map pointer to store
1144 * a little bit of information. There should be at least
1145 * 3 bits here due to 32-bit alignment.
1147 #define SECTION_MARKED_PRESENT (1UL<<0)
1148 #define SECTION_HAS_MEM_MAP (1UL<<1)
1149 #define SECTION_MAP_LAST_BIT (1UL<<2)
1150 #define SECTION_MAP_MASK (~(SECTION_MAP_LAST_BIT-1))
1151 #define SECTION_NID_SHIFT 2
1153 static inline struct page *__section_mem_map_addr(struct mem_section *section)
1155 unsigned long map = section->section_mem_map;
1156 map &= SECTION_MAP_MASK;
1157 return (struct page *)map;
1160 static inline int present_section(struct mem_section *section)
1162 return (section && (section->section_mem_map & SECTION_MARKED_PRESENT));
1165 static inline int present_section_nr(unsigned long nr)
1167 return present_section(__nr_to_section(nr));
1170 static inline int valid_section(struct mem_section *section)
1172 return (section && (section->section_mem_map & SECTION_HAS_MEM_MAP));
1175 static inline int valid_section_nr(unsigned long nr)
1177 return valid_section(__nr_to_section(nr));
1180 static inline struct mem_section *__pfn_to_section(unsigned long pfn)
1182 return __nr_to_section(pfn_to_section_nr(pfn));
1185 #ifndef CONFIG_HAVE_ARCH_PFN_VALID
1186 static inline int pfn_valid(unsigned long pfn)
1188 if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS)
1190 return valid_section(__nr_to_section(pfn_to_section_nr(pfn)));
1194 static inline int pfn_present(unsigned long pfn)
1196 if (pfn_to_section_nr(pfn) >= NR_MEM_SECTIONS)
1198 return present_section(__nr_to_section(pfn_to_section_nr(pfn)));
1202 * These are _only_ used during initialisation, therefore they
1203 * can use __initdata ... They could have names to indicate
1207 #define pfn_to_nid(pfn) \
1209 unsigned long __pfn_to_nid_pfn = (pfn); \
1210 page_to_nid(pfn_to_page(__pfn_to_nid_pfn)); \
1213 #define pfn_to_nid(pfn) (0)
1216 #define early_pfn_valid(pfn) pfn_valid(pfn)
1217 void sparse_init(void);
1219 #define sparse_init() do {} while (0)
1220 #define sparse_index_init(_sec, _nid) do {} while (0)
1221 #endif /* CONFIG_SPARSEMEM */
1224 * During memory init memblocks map pfns to nids. The search is expensive and
1225 * this caches recent lookups. The implementation of __early_pfn_to_nid
1226 * may treat start/end as pfns or sections.
1228 struct mminit_pfnnid_cache {
1229 unsigned long last_start;
1230 unsigned long last_end;
1234 #ifndef early_pfn_valid
1235 #define early_pfn_valid(pfn) (1)
1238 void memory_present(int nid, unsigned long start, unsigned long end);
1239 unsigned long __init node_memmap_size_bytes(int, unsigned long, unsigned long);
1242 * If it is possible to have holes within a MAX_ORDER_NR_PAGES, then we
1243 * need to check pfn validility within that MAX_ORDER_NR_PAGES block.
1244 * pfn_valid_within() should be used in this case; we optimise this away
1245 * when we have no holes within a MAX_ORDER_NR_PAGES block.
1247 #ifdef CONFIG_HOLES_IN_ZONE
1248 #define pfn_valid_within(pfn) pfn_valid(pfn)
1250 #define pfn_valid_within(pfn) (1)
1253 #ifdef CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
1255 * pfn_valid() is meant to be able to tell if a given PFN has valid memmap
1256 * associated with it or not. In FLATMEM, it is expected that holes always
1257 * have valid memmap as long as there is valid PFNs either side of the hole.
1258 * In SPARSEMEM, it is assumed that a valid section has a memmap for the
1261 * However, an ARM, and maybe other embedded architectures in the future
1262 * free memmap backing holes to save memory on the assumption the memmap is
1263 * never used. The page_zone linkages are then broken even though pfn_valid()
1264 * returns true. A walker of the full memmap must then do this additional
1265 * check to ensure the memmap they are looking at is sane by making sure
1266 * the zone and PFN linkages are still valid. This is expensive, but walkers
1267 * of the full memmap are extremely rare.
1269 bool memmap_valid_within(unsigned long pfn,
1270 struct page *page, struct zone *zone);
1272 static inline bool memmap_valid_within(unsigned long pfn,
1273 struct page *page, struct zone *zone)
1277 #endif /* CONFIG_ARCH_HAS_HOLES_MEMORYMODEL */
1279 #endif /* !__GENERATING_BOUNDS.H */
1280 #endif /* !__ASSEMBLY__ */
1281 #endif /* _LINUX_MMZONE_H */