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)
71 # define is_migrate_cma_page(_page) (get_pageblock_migratetype(_page) == MIGRATE_CMA)
73 # define is_migrate_cma(migratetype) false
74 # define is_migrate_cma_page(_page) false
77 static inline bool is_migrate_movable(int mt
)
79 return is_migrate_cma(mt
) || mt
== MIGRATE_MOVABLE
;
82 #define for_each_migratetype_order(order, type) \
83 for (order = 0; order < MAX_ORDER; order++) \
84 for (type = 0; type < MIGRATE_TYPES; type++)
86 extern int page_group_by_mobility_disabled
;
88 #define NR_MIGRATETYPE_BITS (PB_migrate_end - PB_migrate + 1)
89 #define MIGRATETYPE_MASK ((1UL << NR_MIGRATETYPE_BITS) - 1)
91 #define get_pageblock_migratetype(page) \
92 get_pfnblock_flags_mask(page, page_to_pfn(page), \
93 PB_migrate_end, MIGRATETYPE_MASK)
96 struct list_head free_list
[MIGRATE_TYPES
];
97 unsigned long nr_free
;
103 * zone->lock and the zone lru_lock are two of the hottest locks in the kernel.
104 * So add a wild amount of padding here to ensure that they fall into separate
105 * cachelines. There are very few zone structures in the machine, so space
106 * consumption is not a concern here.
108 #if defined(CONFIG_SMP)
109 struct zone_padding
{
111 } ____cacheline_internodealigned_in_smp
;
112 #define ZONE_PADDING(name) struct zone_padding name;
114 #define ZONE_PADDING(name)
118 enum numa_stat_item
{
119 NUMA_HIT
, /* allocated in intended node */
120 NUMA_MISS
, /* allocated in non intended node */
121 NUMA_FOREIGN
, /* was intended here, hit elsewhere */
122 NUMA_INTERLEAVE_HIT
, /* interleaver preferred this zone */
123 NUMA_LOCAL
, /* allocation from local node */
124 NUMA_OTHER
, /* allocation from other node */
125 NR_VM_NUMA_STAT_ITEMS
128 #define NR_VM_NUMA_STAT_ITEMS 0
131 enum zone_stat_item
{
132 /* First 128 byte cacheline (assuming 64 bit words) */
134 NR_ZONE_LRU_BASE
, /* Used only for compaction and reclaim retry */
135 NR_ZONE_INACTIVE_ANON
= NR_ZONE_LRU_BASE
,
137 NR_ZONE_INACTIVE_FILE
,
140 NR_ZONE_WRITE_PENDING
, /* Count of dirty, writeback and unstable pages */
141 NR_MLOCK
, /* mlock()ed pages found and moved off LRU */
142 NR_PAGETABLE
, /* used for pagetables */
143 NR_KERNEL_STACK_KB
, /* measured in KiB */
144 /* Second 128 byte cacheline */
146 #if IS_ENABLED(CONFIG_ZSMALLOC)
147 NR_ZSPAGES
, /* allocated in zsmalloc */
150 NR_VM_ZONE_STAT_ITEMS
};
152 enum node_stat_item
{
154 NR_INACTIVE_ANON
= NR_LRU_BASE
, /* must match order of LRU_[IN]ACTIVE */
155 NR_ACTIVE_ANON
, /* " " " " " */
156 NR_INACTIVE_FILE
, /* " " " " " */
157 NR_ACTIVE_FILE
, /* " " " " " */
158 NR_UNEVICTABLE
, /* " " " " " */
160 NR_SLAB_UNRECLAIMABLE
,
161 NR_ISOLATED_ANON
, /* Temporary isolated pages from anon lru */
162 NR_ISOLATED_FILE
, /* Temporary isolated pages from file lru */
165 WORKINGSET_NODERECLAIM
,
166 NR_ANON_MAPPED
, /* Mapped anonymous pages */
167 NR_FILE_MAPPED
, /* pagecache pages mapped into pagetables.
168 only modified from process context */
172 NR_WRITEBACK_TEMP
, /* Writeback using temporary buffers */
173 NR_SHMEM
, /* shmem pages (included tmpfs/GEM pages) */
177 NR_UNSTABLE_NFS
, /* NFS unstable pages */
179 NR_VMSCAN_IMMEDIATE
, /* Prioritise for reclaim when writeback ends */
180 NR_DIRTIED
, /* page dirtyings since bootup */
181 NR_WRITTEN
, /* page writings since bootup */
182 NR_VM_NODE_STAT_ITEMS
186 * We do arithmetic on the LRU lists in various places in the code,
187 * so it is important to keep the active lists LRU_ACTIVE higher in
188 * the array than the corresponding inactive lists, and to keep
189 * the *_FILE lists LRU_FILE higher than the corresponding _ANON lists.
191 * This has to be kept in sync with the statistics in zone_stat_item
192 * above and the descriptions in vmstat_text in mm/vmstat.c
199 LRU_INACTIVE_ANON
= LRU_BASE
,
200 LRU_ACTIVE_ANON
= LRU_BASE
+ LRU_ACTIVE
,
201 LRU_INACTIVE_FILE
= LRU_BASE
+ LRU_FILE
,
202 LRU_ACTIVE_FILE
= LRU_BASE
+ LRU_FILE
+ LRU_ACTIVE
,
207 #define for_each_lru(lru) for (lru = 0; lru < NR_LRU_LISTS; lru++)
209 #define for_each_evictable_lru(lru) for (lru = 0; lru <= LRU_ACTIVE_FILE; lru++)
211 static inline int is_file_lru(enum lru_list lru
)
213 return (lru
== LRU_INACTIVE_FILE
|| lru
== LRU_ACTIVE_FILE
);
216 static inline int is_active_lru(enum lru_list lru
)
218 return (lru
== LRU_ACTIVE_ANON
|| lru
== LRU_ACTIVE_FILE
);
221 struct zone_reclaim_stat
{
223 * The pageout code in vmscan.c keeps track of how many of the
224 * mem/swap backed and file backed pages are referenced.
225 * The higher the rotated/scanned ratio, the more valuable
228 * The anon LRU stats live in [0], file LRU stats in [1]
230 unsigned long recent_rotated
[2];
231 unsigned long recent_scanned
[2];
235 struct list_head lists
[NR_LRU_LISTS
];
236 struct zone_reclaim_stat reclaim_stat
;
237 /* Evictions & activations on the inactive file list */
238 atomic_long_t inactive_age
;
239 /* Refaults at the time of last reclaim cycle */
240 unsigned long refaults
;
242 struct pglist_data
*pgdat
;
246 /* Mask used at gathering information at once (see memcontrol.c) */
247 #define LRU_ALL_FILE (BIT(LRU_INACTIVE_FILE) | BIT(LRU_ACTIVE_FILE))
248 #define LRU_ALL_ANON (BIT(LRU_INACTIVE_ANON) | BIT(LRU_ACTIVE_ANON))
249 #define LRU_ALL ((1 << NR_LRU_LISTS) - 1)
251 /* Isolate unmapped file */
252 #define ISOLATE_UNMAPPED ((__force isolate_mode_t)0x2)
253 /* Isolate for asynchronous migration */
254 #define ISOLATE_ASYNC_MIGRATE ((__force isolate_mode_t)0x4)
255 /* Isolate unevictable pages */
256 #define ISOLATE_UNEVICTABLE ((__force isolate_mode_t)0x8)
258 /* LRU Isolation modes. */
259 typedef unsigned __bitwise isolate_mode_t
;
261 enum zone_watermarks
{
268 #define min_wmark_pages(z) (z->watermark[WMARK_MIN])
269 #define low_wmark_pages(z) (z->watermark[WMARK_LOW])
270 #define high_wmark_pages(z) (z->watermark[WMARK_HIGH])
272 struct per_cpu_pages
{
273 int count
; /* number of pages in the list */
274 int high
; /* high watermark, emptying needed */
275 int batch
; /* chunk size for buddy add/remove */
277 /* Lists of pages, one per migrate type stored on the pcp-lists */
278 struct list_head lists
[MIGRATE_PCPTYPES
];
281 struct per_cpu_pageset
{
282 struct per_cpu_pages pcp
;
285 u16 vm_numa_stat_diff
[NR_VM_NUMA_STAT_ITEMS
];
289 s8 vm_stat_diff
[NR_VM_ZONE_STAT_ITEMS
];
293 struct per_cpu_nodestat
{
295 s8 vm_node_stat_diff
[NR_VM_NODE_STAT_ITEMS
];
298 #endif /* !__GENERATING_BOUNDS.H */
301 #ifdef CONFIG_ZONE_DMA
303 * ZONE_DMA is used when there are devices that are not able
304 * to do DMA to all of addressable memory (ZONE_NORMAL). Then we
305 * carve out the portion of memory that is needed for these devices.
306 * The range is arch specific.
311 * ---------------------------
312 * parisc, ia64, sparc <4G
315 * alpha Unlimited or 0-16MB.
317 * i386, x86_64 and multiple other arches
322 #ifdef CONFIG_ZONE_DMA32
324 * x86_64 needs two ZONE_DMAs because it supports devices that are
325 * only able to do DMA to the lower 16M but also 32 bit devices that
326 * can only do DMA areas below 4G.
331 * Normal addressable memory is in ZONE_NORMAL. DMA operations can be
332 * performed on pages in ZONE_NORMAL if the DMA devices support
333 * transfers to all addressable memory.
336 #ifdef CONFIG_HIGHMEM
338 * A memory area that is only addressable by the kernel through
339 * mapping portions into its own address space. This is for example
340 * used by i386 to allow the kernel to address the memory beyond
341 * 900MB. The kernel will set up special mappings (page
342 * table entries on i386) for each page that the kernel needs to
348 #ifdef CONFIG_ZONE_DEVICE
355 #ifndef __GENERATING_BOUNDS_H
358 /* Read-mostly fields */
360 /* zone watermarks, access with *_wmark_pages(zone) macros */
361 unsigned long watermark
[NR_WMARK
];
363 unsigned long nr_reserved_highatomic
;
366 * We don't know if the memory that we're going to allocate will be
367 * freeable or/and it will be released eventually, so to avoid totally
368 * wasting several GB of ram we must reserve some of the lower zone
369 * memory (otherwise we risk to run OOM on the lower zones despite
370 * there being tons of freeable ram on the higher zones). This array is
371 * recalculated at runtime if the sysctl_lowmem_reserve_ratio sysctl
374 long lowmem_reserve
[MAX_NR_ZONES
];
379 struct pglist_data
*zone_pgdat
;
380 struct per_cpu_pageset __percpu
*pageset
;
382 #ifndef CONFIG_SPARSEMEM
384 * Flags for a pageblock_nr_pages block. See pageblock-flags.h.
385 * In SPARSEMEM, this map is stored in struct mem_section
387 unsigned long *pageblock_flags
;
388 #endif /* CONFIG_SPARSEMEM */
390 /* zone_start_pfn == zone_start_paddr >> PAGE_SHIFT */
391 unsigned long zone_start_pfn
;
394 * spanned_pages is the total pages spanned by the zone, including
395 * holes, which is calculated as:
396 * spanned_pages = zone_end_pfn - zone_start_pfn;
398 * present_pages is physical pages existing within the zone, which
400 * present_pages = spanned_pages - absent_pages(pages in holes);
402 * managed_pages is present pages managed by the buddy system, which
403 * is calculated as (reserved_pages includes pages allocated by the
404 * bootmem allocator):
405 * managed_pages = present_pages - reserved_pages;
407 * So present_pages may be used by memory hotplug or memory power
408 * management logic to figure out unmanaged pages by checking
409 * (present_pages - managed_pages). And managed_pages should be used
410 * by page allocator and vm scanner to calculate all kinds of watermarks
415 * zone_start_pfn and spanned_pages are protected by span_seqlock.
416 * It is a seqlock because it has to be read outside of zone->lock,
417 * and it is done in the main allocator path. But, it is written
418 * quite infrequently.
420 * The span_seq lock is declared along with zone->lock because it is
421 * frequently read in proximity to zone->lock. It's good to
422 * give them a chance of being in the same cacheline.
424 * Write access to present_pages at runtime should be protected by
425 * mem_hotplug_begin/end(). Any reader who can't tolerant drift of
426 * present_pages should get_online_mems() to get a stable value.
428 * Read access to managed_pages should be safe because it's unsigned
429 * long. Write access to zone->managed_pages and totalram_pages are
430 * protected by managed_page_count_lock at runtime. Idealy only
431 * adjust_managed_page_count() should be used instead of directly
432 * touching zone->managed_pages and totalram_pages.
434 unsigned long managed_pages
;
435 unsigned long spanned_pages
;
436 unsigned long present_pages
;
440 #ifdef CONFIG_MEMORY_ISOLATION
442 * Number of isolated pageblock. It is used to solve incorrect
443 * freepage counting problem due to racy retrieving migratetype
444 * of pageblock. Protected by zone->lock.
446 unsigned long nr_isolate_pageblock
;
449 #ifdef CONFIG_MEMORY_HOTPLUG
450 /* see spanned/present_pages for more description */
451 seqlock_t span_seqlock
;
456 /* Write-intensive fields used from the page allocator */
459 /* free areas of different sizes */
460 struct free_area free_area
[MAX_ORDER
];
462 /* zone flags, see below */
465 /* Primarily protects free_area */
468 /* Write-intensive fields used by compaction and vmstats. */
472 * When free pages are below this point, additional steps are taken
473 * when reading the number of free pages to avoid per-cpu counter
474 * drift allowing watermarks to be breached
476 unsigned long percpu_drift_mark
;
478 #if defined CONFIG_COMPACTION || defined CONFIG_CMA
479 /* pfn where compaction free scanner should start */
480 unsigned long compact_cached_free_pfn
;
481 /* pfn where async and sync compaction migration scanner should start */
482 unsigned long compact_cached_migrate_pfn
[2];
485 #ifdef CONFIG_COMPACTION
487 * On compaction failure, 1<<compact_defer_shift compactions
488 * are skipped before trying again. The number attempted since
489 * last failure is tracked with compact_considered.
491 unsigned int compact_considered
;
492 unsigned int compact_defer_shift
;
493 int compact_order_failed
;
496 #if defined CONFIG_COMPACTION || defined CONFIG_CMA
497 /* Set to true when the PG_migrate_skip bits should be cleared */
498 bool compact_blockskip_flush
;
504 /* Zone statistics */
505 atomic_long_t vm_stat
[NR_VM_ZONE_STAT_ITEMS
];
506 atomic_long_t vm_numa_stat
[NR_VM_NUMA_STAT_ITEMS
];
507 } ____cacheline_internodealigned_in_smp
;
510 PGDAT_CONGESTED
, /* pgdat has many dirty pages backed by
513 PGDAT_DIRTY
, /* reclaim scanning has recently found
514 * many dirty file pages at the tail
517 PGDAT_WRITEBACK
, /* reclaim scanning has recently found
518 * many pages under writeback
520 PGDAT_RECLAIM_LOCKED
, /* prevents concurrent reclaim */
523 static inline unsigned long zone_end_pfn(const struct zone
*zone
)
525 return zone
->zone_start_pfn
+ zone
->spanned_pages
;
528 static inline bool zone_spans_pfn(const struct zone
*zone
, unsigned long pfn
)
530 return zone
->zone_start_pfn
<= pfn
&& pfn
< zone_end_pfn(zone
);
533 static inline bool zone_is_initialized(struct zone
*zone
)
535 return zone
->initialized
;
538 static inline bool zone_is_empty(struct zone
*zone
)
540 return zone
->spanned_pages
== 0;
544 * Return true if [start_pfn, start_pfn + nr_pages) range has a non-empty
545 * intersection with the given zone
547 static inline bool zone_intersects(struct zone
*zone
,
548 unsigned long start_pfn
, unsigned long nr_pages
)
550 if (zone_is_empty(zone
))
552 if (start_pfn
>= zone_end_pfn(zone
) ||
553 start_pfn
+ nr_pages
<= zone
->zone_start_pfn
)
560 * The "priority" of VM scanning is how much of the queues we will scan in one
561 * go. A value of 12 for DEF_PRIORITY implies that we will scan 1/4096th of the
562 * queues ("queue_length >> 12") during an aging round.
564 #define DEF_PRIORITY 12
566 /* Maximum number of zones on a zonelist */
567 #define MAX_ZONES_PER_ZONELIST (MAX_NUMNODES * MAX_NR_ZONES)
570 ZONELIST_FALLBACK
, /* zonelist with fallback */
573 * The NUMA zonelists are doubled because we need zonelists that
574 * restrict the allocations to a single node for __GFP_THISNODE.
576 ZONELIST_NOFALLBACK
, /* zonelist without fallback (__GFP_THISNODE) */
582 * This struct contains information about a zone in a zonelist. It is stored
583 * here to avoid dereferences into large structures and lookups of tables
586 struct zone
*zone
; /* Pointer to actual zone */
587 int zone_idx
; /* zone_idx(zoneref->zone) */
591 * One allocation request operates on a zonelist. A zonelist
592 * is a list of zones, the first one is the 'goal' of the
593 * allocation, the other zones are fallback zones, in decreasing
596 * To speed the reading of the zonelist, the zonerefs contain the zone index
597 * of the entry being read. Helper functions to access information given
598 * a struct zoneref are
600 * zonelist_zone() - Return the struct zone * for an entry in _zonerefs
601 * zonelist_zone_idx() - Return the index of the zone for an entry
602 * zonelist_node_idx() - Return the index of the node for an entry
605 struct zoneref _zonerefs
[MAX_ZONES_PER_ZONELIST
+ 1];
608 #ifndef CONFIG_DISCONTIGMEM
609 /* The array of struct pages - for discontigmem use pgdat->lmem_map */
610 extern struct page
*mem_map
;
614 * On NUMA machines, each NUMA node would have a pg_data_t to describe
615 * it's memory layout. On UMA machines there is a single pglist_data which
616 * describes the whole memory.
618 * Memory statistics and page replacement data structures are maintained on a
622 typedef struct pglist_data
{
623 struct zone node_zones
[MAX_NR_ZONES
];
624 struct zonelist node_zonelists
[MAX_ZONELISTS
];
626 #ifdef CONFIG_FLAT_NODE_MEM_MAP /* means !SPARSEMEM */
627 struct page
*node_mem_map
;
628 #ifdef CONFIG_PAGE_EXTENSION
629 struct page_ext
*node_page_ext
;
632 #ifndef CONFIG_NO_BOOTMEM
633 struct bootmem_data
*bdata
;
635 #ifdef CONFIG_MEMORY_HOTPLUG
637 * Must be held any time you expect node_start_pfn, node_present_pages
638 * or node_spanned_pages stay constant. Holding this will also
639 * guarantee that any pfn_valid() stays that way.
641 * pgdat_resize_lock() and pgdat_resize_unlock() are provided to
642 * manipulate node_size_lock without checking for CONFIG_MEMORY_HOTPLUG.
644 * Nests above zone->lock and zone->span_seqlock
646 spinlock_t node_size_lock
;
648 unsigned long node_start_pfn
;
649 unsigned long node_present_pages
; /* total number of physical pages */
650 unsigned long node_spanned_pages
; /* total size of physical page
651 range, including holes */
653 wait_queue_head_t kswapd_wait
;
654 wait_queue_head_t pfmemalloc_wait
;
655 struct task_struct
*kswapd
; /* Protected by
656 mem_hotplug_begin/end() */
658 enum zone_type kswapd_classzone_idx
;
660 int kswapd_failures
; /* Number of 'reclaimed == 0' runs */
662 #ifdef CONFIG_COMPACTION
663 int kcompactd_max_order
;
664 enum zone_type kcompactd_classzone_idx
;
665 wait_queue_head_t kcompactd_wait
;
666 struct task_struct
*kcompactd
;
668 #ifdef CONFIG_NUMA_BALANCING
669 /* Lock serializing the migrate rate limiting window */
670 spinlock_t numabalancing_migrate_lock
;
672 /* Rate limiting time interval */
673 unsigned long numabalancing_migrate_next_window
;
675 /* Number of pages migrated during the rate limiting time interval */
676 unsigned long numabalancing_migrate_nr_pages
;
679 * This is a per-node reserve of pages that are not available
680 * to userspace allocations.
682 unsigned long totalreserve_pages
;
686 * zone reclaim becomes active if more unmapped pages exist.
688 unsigned long min_unmapped_pages
;
689 unsigned long min_slab_pages
;
690 #endif /* CONFIG_NUMA */
692 /* Write-intensive fields used by page reclaim */
696 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
698 * If memory initialisation on large machines is deferred then this
699 * is the first PFN that needs to be initialised.
701 unsigned long first_deferred_pfn
;
702 unsigned long static_init_size
;
703 #endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */
705 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
706 spinlock_t split_queue_lock
;
707 struct list_head split_queue
;
708 unsigned long split_queue_len
;
711 /* Fields commonly accessed by the page reclaim scanner */
712 struct lruvec lruvec
;
715 * The target ratio of ACTIVE_ANON to INACTIVE_ANON pages on
716 * this node's LRU. Maintained by the pageout code.
718 unsigned int inactive_ratio
;
724 /* Per-node vmstats */
725 struct per_cpu_nodestat __percpu
*per_cpu_nodestats
;
726 atomic_long_t vm_stat
[NR_VM_NODE_STAT_ITEMS
];
729 #define node_present_pages(nid) (NODE_DATA(nid)->node_present_pages)
730 #define node_spanned_pages(nid) (NODE_DATA(nid)->node_spanned_pages)
731 #ifdef CONFIG_FLAT_NODE_MEM_MAP
732 #define pgdat_page_nr(pgdat, pagenr) ((pgdat)->node_mem_map + (pagenr))
734 #define pgdat_page_nr(pgdat, pagenr) pfn_to_page((pgdat)->node_start_pfn + (pagenr))
736 #define nid_page_nr(nid, pagenr) pgdat_page_nr(NODE_DATA(nid),(pagenr))
738 #define node_start_pfn(nid) (NODE_DATA(nid)->node_start_pfn)
739 #define node_end_pfn(nid) pgdat_end_pfn(NODE_DATA(nid))
740 static inline spinlock_t
*zone_lru_lock(struct zone
*zone
)
742 return &zone
->zone_pgdat
->lru_lock
;
745 static inline struct lruvec
*node_lruvec(struct pglist_data
*pgdat
)
747 return &pgdat
->lruvec
;
750 static inline unsigned long pgdat_end_pfn(pg_data_t
*pgdat
)
752 return pgdat
->node_start_pfn
+ pgdat
->node_spanned_pages
;
755 static inline bool pgdat_is_empty(pg_data_t
*pgdat
)
757 return !pgdat
->node_start_pfn
&& !pgdat
->node_spanned_pages
;
760 static inline int zone_id(const struct zone
*zone
)
762 struct pglist_data
*pgdat
= zone
->zone_pgdat
;
764 return zone
- pgdat
->node_zones
;
767 #ifdef CONFIG_ZONE_DEVICE
768 static inline bool is_dev_zone(const struct zone
*zone
)
770 return zone_id(zone
) == ZONE_DEVICE
;
773 static inline bool is_dev_zone(const struct zone
*zone
)
779 #include <linux/memory_hotplug.h>
781 void build_all_zonelists(pg_data_t
*pgdat
);
782 void wakeup_kswapd(struct zone
*zone
, int order
, enum zone_type classzone_idx
);
783 bool __zone_watermark_ok(struct zone
*z
, unsigned int order
, unsigned long mark
,
784 int classzone_idx
, unsigned int alloc_flags
,
786 bool zone_watermark_ok(struct zone
*z
, unsigned int order
,
787 unsigned long mark
, int classzone_idx
,
788 unsigned int alloc_flags
);
789 bool zone_watermark_ok_safe(struct zone
*z
, unsigned int order
,
790 unsigned long mark
, int classzone_idx
);
791 enum memmap_context
{
795 extern void init_currently_empty_zone(struct zone
*zone
, unsigned long start_pfn
,
798 extern void lruvec_init(struct lruvec
*lruvec
);
800 static inline struct pglist_data
*lruvec_pgdat(struct lruvec
*lruvec
)
803 return lruvec
->pgdat
;
805 return container_of(lruvec
, struct pglist_data
, lruvec
);
809 extern unsigned long lruvec_lru_size(struct lruvec
*lruvec
, enum lru_list lru
, int zone_idx
);
811 #ifdef CONFIG_HAVE_MEMORY_PRESENT
812 void memory_present(int nid
, unsigned long start
, unsigned long end
);
814 static inline void memory_present(int nid
, unsigned long start
, unsigned long end
) {}
817 #ifdef CONFIG_HAVE_MEMORYLESS_NODES
818 int local_memory_node(int node_id
);
820 static inline int local_memory_node(int node_id
) { return node_id
; };
823 #ifdef CONFIG_NEED_NODE_MEMMAP_SIZE
824 unsigned long __init
node_memmap_size_bytes(int, unsigned long, unsigned long);
828 * zone_idx() returns 0 for the ZONE_DMA zone, 1 for the ZONE_NORMAL zone, etc.
830 #define zone_idx(zone) ((zone) - (zone)->zone_pgdat->node_zones)
833 * Returns true if a zone has pages managed by the buddy allocator.
834 * All the reclaim decisions have to use this function rather than
835 * populated_zone(). If the whole zone is reserved then we can easily
836 * end up with populated_zone() && !managed_zone().
838 static inline bool managed_zone(struct zone
*zone
)
840 return zone
->managed_pages
;
843 /* Returns true if a zone has memory */
844 static inline bool populated_zone(struct zone
*zone
)
846 return zone
->present_pages
;
849 extern int movable_zone
;
851 #ifdef CONFIG_HIGHMEM
852 static inline int zone_movable_is_highmem(void)
854 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
855 return movable_zone
== ZONE_HIGHMEM
;
857 return (ZONE_MOVABLE
- 1) == ZONE_HIGHMEM
;
862 static inline int is_highmem_idx(enum zone_type idx
)
864 #ifdef CONFIG_HIGHMEM
865 return (idx
== ZONE_HIGHMEM
||
866 (idx
== ZONE_MOVABLE
&& zone_movable_is_highmem()));
873 * is_highmem - helper function to quickly check if a struct zone is a
874 * highmem zone or not. This is an attempt to keep references
875 * to ZONE_{DMA/NORMAL/HIGHMEM/etc} in general code to a minimum.
876 * @zone - pointer to struct zone variable
878 static inline int is_highmem(struct zone
*zone
)
880 #ifdef CONFIG_HIGHMEM
881 return is_highmem_idx(zone_idx(zone
));
887 /* These two functions are used to setup the per zone pages min values */
889 int min_free_kbytes_sysctl_handler(struct ctl_table
*, int,
890 void __user
*, size_t *, loff_t
*);
891 int watermark_scale_factor_sysctl_handler(struct ctl_table
*, int,
892 void __user
*, size_t *, loff_t
*);
893 extern int sysctl_lowmem_reserve_ratio
[MAX_NR_ZONES
-1];
894 int lowmem_reserve_ratio_sysctl_handler(struct ctl_table
*, int,
895 void __user
*, size_t *, loff_t
*);
896 int percpu_pagelist_fraction_sysctl_handler(struct ctl_table
*, int,
897 void __user
*, size_t *, loff_t
*);
898 int sysctl_min_unmapped_ratio_sysctl_handler(struct ctl_table
*, int,
899 void __user
*, size_t *, loff_t
*);
900 int sysctl_min_slab_ratio_sysctl_handler(struct ctl_table
*, int,
901 void __user
*, size_t *, loff_t
*);
903 extern int numa_zonelist_order_handler(struct ctl_table
*, int,
904 void __user
*, size_t *, loff_t
*);
905 extern char numa_zonelist_order
[];
906 #define NUMA_ZONELIST_ORDER_LEN 16
908 #ifndef CONFIG_NEED_MULTIPLE_NODES
910 extern struct pglist_data contig_page_data
;
911 #define NODE_DATA(nid) (&contig_page_data)
912 #define NODE_MEM_MAP(nid) mem_map
914 #else /* CONFIG_NEED_MULTIPLE_NODES */
916 #include <asm/mmzone.h>
918 #endif /* !CONFIG_NEED_MULTIPLE_NODES */
920 extern struct pglist_data
*first_online_pgdat(void);
921 extern struct pglist_data
*next_online_pgdat(struct pglist_data
*pgdat
);
922 extern struct zone
*next_zone(struct zone
*zone
);
925 * for_each_online_pgdat - helper macro to iterate over all online nodes
926 * @pgdat - pointer to a pg_data_t variable
928 #define for_each_online_pgdat(pgdat) \
929 for (pgdat = first_online_pgdat(); \
931 pgdat = next_online_pgdat(pgdat))
933 * for_each_zone - helper macro to iterate over all memory zones
934 * @zone - pointer to struct zone variable
936 * The user only needs to declare the zone variable, for_each_zone
939 #define for_each_zone(zone) \
940 for (zone = (first_online_pgdat())->node_zones; \
942 zone = next_zone(zone))
944 #define for_each_populated_zone(zone) \
945 for (zone = (first_online_pgdat())->node_zones; \
947 zone = next_zone(zone)) \
948 if (!populated_zone(zone)) \
952 static inline struct zone
*zonelist_zone(struct zoneref
*zoneref
)
954 return zoneref
->zone
;
957 static inline int zonelist_zone_idx(struct zoneref
*zoneref
)
959 return zoneref
->zone_idx
;
962 static inline int zonelist_node_idx(struct zoneref
*zoneref
)
965 /* zone_to_nid not available in this context */
966 return zoneref
->zone
->node
;
969 #endif /* CONFIG_NUMA */
972 struct zoneref
*__next_zones_zonelist(struct zoneref
*z
,
973 enum zone_type highest_zoneidx
,
977 * 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
978 * @z - The cursor used as a starting point for the search
979 * @highest_zoneidx - The zone index of the highest zone to return
980 * @nodes - An optional nodemask to filter the zonelist with
982 * This function returns the next zone at or below a given zone index that is
983 * within the allowed nodemask using a cursor as the starting point for the
984 * search. The zoneref returned is a cursor that represents the current zone
985 * being examined. It should be advanced by one before calling
986 * next_zones_zonelist again.
988 static __always_inline
struct zoneref
*next_zones_zonelist(struct zoneref
*z
,
989 enum zone_type highest_zoneidx
,
992 if (likely(!nodes
&& zonelist_zone_idx(z
) <= highest_zoneidx
))
994 return __next_zones_zonelist(z
, highest_zoneidx
, nodes
);
998 * first_zones_zonelist - Returns the first zone at or below highest_zoneidx within the allowed nodemask in a zonelist
999 * @zonelist - The zonelist to search for a suitable zone
1000 * @highest_zoneidx - The zone index of the highest zone to return
1001 * @nodes - An optional nodemask to filter the zonelist with
1002 * @return - Zoneref pointer for the first suitable zone found (see below)
1004 * This function returns the first zone at or below a given zone index that is
1005 * within the allowed nodemask. The zoneref returned is a cursor that can be
1006 * used to iterate the zonelist with next_zones_zonelist by advancing it by
1007 * one before calling.
1009 * When no eligible zone is found, zoneref->zone is NULL (zoneref itself is
1010 * never NULL). This may happen either genuinely, or due to concurrent nodemask
1011 * update due to cpuset modification.
1013 static inline struct zoneref
*first_zones_zonelist(struct zonelist
*zonelist
,
1014 enum zone_type highest_zoneidx
,
1017 return next_zones_zonelist(zonelist
->_zonerefs
,
1018 highest_zoneidx
, nodes
);
1022 * 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
1023 * @zone - The current zone in the iterator
1024 * @z - The current pointer within zonelist->zones being iterated
1025 * @zlist - The zonelist being iterated
1026 * @highidx - The zone index of the highest zone to return
1027 * @nodemask - Nodemask allowed by the allocator
1029 * This iterator iterates though all zones at or below a given zone index and
1030 * within a given nodemask
1032 #define for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, nodemask) \
1033 for (z = first_zones_zonelist(zlist, highidx, nodemask), zone = zonelist_zone(z); \
1035 z = next_zones_zonelist(++z, highidx, nodemask), \
1036 zone = zonelist_zone(z))
1038 #define for_next_zone_zonelist_nodemask(zone, z, zlist, highidx, nodemask) \
1039 for (zone = z->zone; \
1041 z = next_zones_zonelist(++z, highidx, nodemask), \
1042 zone = zonelist_zone(z))
1046 * for_each_zone_zonelist - helper macro to iterate over valid zones in a zonelist at or below a given zone index
1047 * @zone - The current zone in the iterator
1048 * @z - The current pointer within zonelist->zones being iterated
1049 * @zlist - The zonelist being iterated
1050 * @highidx - The zone index of the highest zone to return
1052 * This iterator iterates though all zones at or below a given zone index.
1054 #define for_each_zone_zonelist(zone, z, zlist, highidx) \
1055 for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, NULL)
1057 #ifdef CONFIG_SPARSEMEM
1058 #include <asm/sparsemem.h>
1061 #if !defined(CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID) && \
1062 !defined(CONFIG_HAVE_MEMBLOCK_NODE_MAP)
1063 static inline unsigned long early_pfn_to_nid(unsigned long pfn
)
1065 BUILD_BUG_ON(IS_ENABLED(CONFIG_NUMA
));
1070 #ifdef CONFIG_FLATMEM
1071 #define pfn_to_nid(pfn) (0)
1074 #ifdef CONFIG_SPARSEMEM
1077 * SECTION_SHIFT #bits space required to store a section #
1079 * PA_SECTION_SHIFT physical address to/from section number
1080 * PFN_SECTION_SHIFT pfn to/from section number
1082 #define PA_SECTION_SHIFT (SECTION_SIZE_BITS)
1083 #define PFN_SECTION_SHIFT (SECTION_SIZE_BITS - PAGE_SHIFT)
1085 #define NR_MEM_SECTIONS (1UL << SECTIONS_SHIFT)
1087 #define PAGES_PER_SECTION (1UL << PFN_SECTION_SHIFT)
1088 #define PAGE_SECTION_MASK (~(PAGES_PER_SECTION-1))
1090 #define SECTION_BLOCKFLAGS_BITS \
1091 ((1UL << (PFN_SECTION_SHIFT - pageblock_order)) * NR_PAGEBLOCK_BITS)
1093 #if (MAX_ORDER - 1 + PAGE_SHIFT) > SECTION_SIZE_BITS
1094 #error Allocator MAX_ORDER exceeds SECTION_SIZE
1097 static inline unsigned long pfn_to_section_nr(unsigned long pfn
)
1099 return pfn
>> PFN_SECTION_SHIFT
;
1101 static inline unsigned long section_nr_to_pfn(unsigned long sec
)
1103 return sec
<< PFN_SECTION_SHIFT
;
1106 #define SECTION_ALIGN_UP(pfn) (((pfn) + PAGES_PER_SECTION - 1) & PAGE_SECTION_MASK)
1107 #define SECTION_ALIGN_DOWN(pfn) ((pfn) & PAGE_SECTION_MASK)
1111 struct mem_section
{
1113 * This is, logically, a pointer to an array of struct
1114 * pages. However, it is stored with some other magic.
1115 * (see sparse.c::sparse_init_one_section())
1117 * Additionally during early boot we encode node id of
1118 * the location of the section here to guide allocation.
1119 * (see sparse.c::memory_present())
1121 * Making it a UL at least makes someone do a cast
1122 * before using it wrong.
1124 unsigned long section_mem_map
;
1126 /* See declaration of similar field in struct zone */
1127 unsigned long *pageblock_flags
;
1128 #ifdef CONFIG_PAGE_EXTENSION
1130 * If SPARSEMEM, pgdat doesn't have page_ext pointer. We use
1131 * section. (see page_ext.h about this.)
1133 struct page_ext
*page_ext
;
1137 * WARNING: mem_section must be a power-of-2 in size for the
1138 * calculation and use of SECTION_ROOT_MASK to make sense.
1142 #ifdef CONFIG_SPARSEMEM_EXTREME
1143 #define SECTIONS_PER_ROOT (PAGE_SIZE / sizeof (struct mem_section))
1145 #define SECTIONS_PER_ROOT 1
1148 #define SECTION_NR_TO_ROOT(sec) ((sec) / SECTIONS_PER_ROOT)
1149 #define NR_SECTION_ROOTS DIV_ROUND_UP(NR_MEM_SECTIONS, SECTIONS_PER_ROOT)
1150 #define SECTION_ROOT_MASK (SECTIONS_PER_ROOT - 1)
1152 #ifdef CONFIG_SPARSEMEM_EXTREME
1153 extern struct mem_section
*mem_section
[NR_SECTION_ROOTS
];
1155 extern struct mem_section mem_section
[NR_SECTION_ROOTS
][SECTIONS_PER_ROOT
];
1158 static inline struct mem_section
*__nr_to_section(unsigned long nr
)
1160 if (!mem_section
[SECTION_NR_TO_ROOT(nr
)])
1162 return &mem_section
[SECTION_NR_TO_ROOT(nr
)][nr
& SECTION_ROOT_MASK
];
1164 extern int __section_nr(struct mem_section
* ms
);
1165 extern unsigned long usemap_size(void);
1168 * We use the lower bits of the mem_map pointer to store
1169 * a little bit of information. There should be at least
1170 * 3 bits here due to 32-bit alignment.
1172 #define SECTION_MARKED_PRESENT (1UL<<0)
1173 #define SECTION_HAS_MEM_MAP (1UL<<1)
1174 #define SECTION_IS_ONLINE (1UL<<2)
1175 #define SECTION_MAP_LAST_BIT (1UL<<3)
1176 #define SECTION_MAP_MASK (~(SECTION_MAP_LAST_BIT-1))
1177 #define SECTION_NID_SHIFT 3
1179 static inline struct page
*__section_mem_map_addr(struct mem_section
*section
)
1181 unsigned long map
= section
->section_mem_map
;
1182 map
&= SECTION_MAP_MASK
;
1183 return (struct page
*)map
;
1186 static inline int present_section(struct mem_section
*section
)
1188 return (section
&& (section
->section_mem_map
& SECTION_MARKED_PRESENT
));
1191 static inline int present_section_nr(unsigned long nr
)
1193 return present_section(__nr_to_section(nr
));
1196 static inline int valid_section(struct mem_section
*section
)
1198 return (section
&& (section
->section_mem_map
& SECTION_HAS_MEM_MAP
));
1201 static inline int valid_section_nr(unsigned long nr
)
1203 return valid_section(__nr_to_section(nr
));
1206 static inline int online_section(struct mem_section
*section
)
1208 return (section
&& (section
->section_mem_map
& SECTION_IS_ONLINE
));
1211 static inline int online_section_nr(unsigned long nr
)
1213 return online_section(__nr_to_section(nr
));
1216 #ifdef CONFIG_MEMORY_HOTPLUG
1217 void online_mem_sections(unsigned long start_pfn
, unsigned long end_pfn
);
1218 #ifdef CONFIG_MEMORY_HOTREMOVE
1219 void offline_mem_sections(unsigned long start_pfn
, unsigned long end_pfn
);
1223 static inline struct mem_section
*__pfn_to_section(unsigned long pfn
)
1225 return __nr_to_section(pfn_to_section_nr(pfn
));
1228 extern int __highest_present_section_nr
;
1230 #ifndef CONFIG_HAVE_ARCH_PFN_VALID
1231 static inline int pfn_valid(unsigned long pfn
)
1233 if (pfn_to_section_nr(pfn
) >= NR_MEM_SECTIONS
)
1235 return valid_section(__nr_to_section(pfn_to_section_nr(pfn
)));
1239 static inline int pfn_present(unsigned long pfn
)
1241 if (pfn_to_section_nr(pfn
) >= NR_MEM_SECTIONS
)
1243 return present_section(__nr_to_section(pfn_to_section_nr(pfn
)));
1247 * These are _only_ used during initialisation, therefore they
1248 * can use __initdata ... They could have names to indicate
1252 #define pfn_to_nid(pfn) \
1254 unsigned long __pfn_to_nid_pfn = (pfn); \
1255 page_to_nid(pfn_to_page(__pfn_to_nid_pfn)); \
1258 #define pfn_to_nid(pfn) (0)
1261 #define early_pfn_valid(pfn) pfn_valid(pfn)
1262 void sparse_init(void);
1264 #define sparse_init() do {} while (0)
1265 #define sparse_index_init(_sec, _nid) do {} while (0)
1266 #endif /* CONFIG_SPARSEMEM */
1269 * During memory init memblocks map pfns to nids. The search is expensive and
1270 * this caches recent lookups. The implementation of __early_pfn_to_nid
1271 * may treat start/end as pfns or sections.
1273 struct mminit_pfnnid_cache
{
1274 unsigned long last_start
;
1275 unsigned long last_end
;
1279 #ifndef early_pfn_valid
1280 #define early_pfn_valid(pfn) (1)
1283 void memory_present(int nid
, unsigned long start
, unsigned long end
);
1284 unsigned long __init
node_memmap_size_bytes(int, unsigned long, unsigned long);
1287 * If it is possible to have holes within a MAX_ORDER_NR_PAGES, then we
1288 * need to check pfn validility within that MAX_ORDER_NR_PAGES block.
1289 * pfn_valid_within() should be used in this case; we optimise this away
1290 * when we have no holes within a MAX_ORDER_NR_PAGES block.
1292 #ifdef CONFIG_HOLES_IN_ZONE
1293 #define pfn_valid_within(pfn) pfn_valid(pfn)
1295 #define pfn_valid_within(pfn) (1)
1298 #ifdef CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
1300 * pfn_valid() is meant to be able to tell if a given PFN has valid memmap
1301 * associated with it or not. This means that a struct page exists for this
1302 * pfn. The caller cannot assume the page is fully initialized in general.
1303 * Hotplugable pages might not have been onlined yet. pfn_to_online_page()
1304 * will ensure the struct page is fully online and initialized. Special pages
1305 * (e.g. ZONE_DEVICE) are never onlined and should be treated accordingly.
1307 * In FLATMEM, it is expected that holes always have valid memmap as long as
1308 * there is valid PFNs either side of the hole. In SPARSEMEM, it is assumed
1309 * that a valid section has a memmap for the entire section.
1311 * However, an ARM, and maybe other embedded architectures in the future
1312 * free memmap backing holes to save memory on the assumption the memmap is
1313 * never used. The page_zone linkages are then broken even though pfn_valid()
1314 * returns true. A walker of the full memmap must then do this additional
1315 * check to ensure the memmap they are looking at is sane by making sure
1316 * the zone and PFN linkages are still valid. This is expensive, but walkers
1317 * of the full memmap are extremely rare.
1319 bool memmap_valid_within(unsigned long pfn
,
1320 struct page
*page
, struct zone
*zone
);
1322 static inline bool memmap_valid_within(unsigned long pfn
,
1323 struct page
*page
, struct zone
*zone
)
1327 #endif /* CONFIG_ARCH_HAS_HOLES_MEMORYMODEL */
1329 #endif /* !__GENERATING_BOUNDS.H */
1330 #endif /* !__ASSEMBLY__ */
1331 #endif /* _LINUX_MMZONE_H */