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_ZONE_WRITE_PENDING
, /* Count of dirty, writeback and unstable pages */
118 NR_MLOCK
, /* mlock()ed pages found and moved off LRU */
120 NR_SLAB_UNRECLAIMABLE
,
121 NR_PAGETABLE
, /* used for pagetables */
123 /* Second 128 byte cacheline */
126 NR_VMSCAN_IMMEDIATE
, /* Prioritise for reclaim when writeback ends */
127 NR_DIRTIED
, /* page dirtyings since bootup */
128 NR_WRITTEN
, /* page writings since bootup */
129 #if IS_ENABLED(CONFIG_ZSMALLOC)
130 NR_ZSPAGES
, /* allocated in zsmalloc */
133 NUMA_HIT
, /* allocated in intended node */
134 NUMA_MISS
, /* allocated in non intended node */
135 NUMA_FOREIGN
, /* was intended here, hit elsewhere */
136 NUMA_INTERLEAVE_HIT
, /* interleaver preferred this zone */
137 NUMA_LOCAL
, /* allocation from local node */
138 NUMA_OTHER
, /* allocation from other node */
141 NR_VM_ZONE_STAT_ITEMS
};
143 enum node_stat_item
{
145 NR_INACTIVE_ANON
= NR_LRU_BASE
, /* must match order of LRU_[IN]ACTIVE */
146 NR_ACTIVE_ANON
, /* " " " " " */
147 NR_INACTIVE_FILE
, /* " " " " " */
148 NR_ACTIVE_FILE
, /* " " " " " */
149 NR_UNEVICTABLE
, /* " " " " " */
150 NR_ISOLATED_ANON
, /* Temporary isolated pages from anon lru */
151 NR_ISOLATED_FILE
, /* Temporary isolated pages from file lru */
152 NR_PAGES_SCANNED
, /* pages scanned since last reclaim */
155 WORKINGSET_NODERECLAIM
,
156 NR_ANON_MAPPED
, /* Mapped anonymous pages */
157 NR_FILE_MAPPED
, /* pagecache pages mapped into pagetables.
158 only modified from process context */
162 NR_WRITEBACK_TEMP
, /* Writeback using temporary buffers */
163 NR_SHMEM
, /* shmem pages (included tmpfs/GEM pages) */
167 NR_UNSTABLE_NFS
, /* NFS unstable pages */
168 NR_VM_NODE_STAT_ITEMS
172 * We do arithmetic on the LRU lists in various places in the code,
173 * so it is important to keep the active lists LRU_ACTIVE higher in
174 * the array than the corresponding inactive lists, and to keep
175 * the *_FILE lists LRU_FILE higher than the corresponding _ANON lists.
177 * This has to be kept in sync with the statistics in zone_stat_item
178 * above and the descriptions in vmstat_text in mm/vmstat.c
185 LRU_INACTIVE_ANON
= LRU_BASE
,
186 LRU_ACTIVE_ANON
= LRU_BASE
+ LRU_ACTIVE
,
187 LRU_INACTIVE_FILE
= LRU_BASE
+ LRU_FILE
,
188 LRU_ACTIVE_FILE
= LRU_BASE
+ LRU_FILE
+ LRU_ACTIVE
,
193 #define for_each_lru(lru) for (lru = 0; lru < NR_LRU_LISTS; lru++)
195 #define for_each_evictable_lru(lru) for (lru = 0; lru <= LRU_ACTIVE_FILE; lru++)
197 static inline int is_file_lru(enum lru_list lru
)
199 return (lru
== LRU_INACTIVE_FILE
|| lru
== LRU_ACTIVE_FILE
);
202 static inline int is_active_lru(enum lru_list lru
)
204 return (lru
== LRU_ACTIVE_ANON
|| lru
== LRU_ACTIVE_FILE
);
207 struct zone_reclaim_stat
{
209 * The pageout code in vmscan.c keeps track of how many of the
210 * mem/swap backed and file backed pages are referenced.
211 * The higher the rotated/scanned ratio, the more valuable
214 * The anon LRU stats live in [0], file LRU stats in [1]
216 unsigned long recent_rotated
[2];
217 unsigned long recent_scanned
[2];
221 struct list_head lists
[NR_LRU_LISTS
];
222 struct zone_reclaim_stat reclaim_stat
;
223 /* Evictions & activations on the inactive file list */
224 atomic_long_t inactive_age
;
226 struct pglist_data
*pgdat
;
230 /* Mask used at gathering information at once (see memcontrol.c) */
231 #define LRU_ALL_FILE (BIT(LRU_INACTIVE_FILE) | BIT(LRU_ACTIVE_FILE))
232 #define LRU_ALL_ANON (BIT(LRU_INACTIVE_ANON) | BIT(LRU_ACTIVE_ANON))
233 #define LRU_ALL ((1 << NR_LRU_LISTS) - 1)
235 /* Isolate clean file */
236 #define ISOLATE_CLEAN ((__force isolate_mode_t)0x1)
237 /* Isolate unmapped file */
238 #define ISOLATE_UNMAPPED ((__force isolate_mode_t)0x2)
239 /* Isolate for asynchronous migration */
240 #define ISOLATE_ASYNC_MIGRATE ((__force isolate_mode_t)0x4)
241 /* Isolate unevictable pages */
242 #define ISOLATE_UNEVICTABLE ((__force isolate_mode_t)0x8)
244 /* LRU Isolation modes. */
245 typedef unsigned __bitwise__ isolate_mode_t
;
247 enum zone_watermarks
{
254 #define min_wmark_pages(z) (z->watermark[WMARK_MIN])
255 #define low_wmark_pages(z) (z->watermark[WMARK_LOW])
256 #define high_wmark_pages(z) (z->watermark[WMARK_HIGH])
258 struct per_cpu_pages
{
259 int count
; /* number of pages in the list */
260 int high
; /* high watermark, emptying needed */
261 int batch
; /* chunk size for buddy add/remove */
263 /* Lists of pages, one per migrate type stored on the pcp-lists */
264 struct list_head lists
[MIGRATE_PCPTYPES
];
267 struct per_cpu_pageset
{
268 struct per_cpu_pages pcp
;
274 s8 vm_stat_diff
[NR_VM_ZONE_STAT_ITEMS
];
278 struct per_cpu_nodestat
{
280 s8 vm_node_stat_diff
[NR_VM_NODE_STAT_ITEMS
];
283 #endif /* !__GENERATING_BOUNDS.H */
286 #ifdef CONFIG_ZONE_DMA
288 * ZONE_DMA is used when there are devices that are not able
289 * to do DMA to all of addressable memory (ZONE_NORMAL). Then we
290 * carve out the portion of memory that is needed for these devices.
291 * The range is arch specific.
296 * ---------------------------
297 * parisc, ia64, sparc <4G
300 * alpha Unlimited or 0-16MB.
302 * i386, x86_64 and multiple other arches
307 #ifdef CONFIG_ZONE_DMA32
309 * x86_64 needs two ZONE_DMAs because it supports devices that are
310 * only able to do DMA to the lower 16M but also 32 bit devices that
311 * can only do DMA areas below 4G.
316 * Normal addressable memory is in ZONE_NORMAL. DMA operations can be
317 * performed on pages in ZONE_NORMAL if the DMA devices support
318 * transfers to all addressable memory.
321 #ifdef CONFIG_HIGHMEM
323 * A memory area that is only addressable by the kernel through
324 * mapping portions into its own address space. This is for example
325 * used by i386 to allow the kernel to address the memory beyond
326 * 900MB. The kernel will set up special mappings (page
327 * table entries on i386) for each page that the kernel needs to
333 #ifdef CONFIG_ZONE_DEVICE
340 #ifndef __GENERATING_BOUNDS_H
343 /* Read-mostly fields */
345 /* zone watermarks, access with *_wmark_pages(zone) macros */
346 unsigned long watermark
[NR_WMARK
];
348 unsigned long nr_reserved_highatomic
;
351 * We don't know if the memory that we're going to allocate will be
352 * freeable or/and it will be released eventually, so to avoid totally
353 * wasting several GB of ram we must reserve some of the lower zone
354 * memory (otherwise we risk to run OOM on the lower zones despite
355 * there being tons of freeable ram on the higher zones). This array is
356 * recalculated at runtime if the sysctl_lowmem_reserve_ratio sysctl
359 long lowmem_reserve
[MAX_NR_ZONES
];
364 struct pglist_data
*zone_pgdat
;
365 struct per_cpu_pageset __percpu
*pageset
;
367 #ifndef CONFIG_SPARSEMEM
369 * Flags for a pageblock_nr_pages block. See pageblock-flags.h.
370 * In SPARSEMEM, this map is stored in struct mem_section
372 unsigned long *pageblock_flags
;
373 #endif /* CONFIG_SPARSEMEM */
377 * zone reclaim becomes active if more unmapped pages exist.
379 unsigned long min_unmapped_pages
;
380 unsigned long min_slab_pages
;
381 #endif /* CONFIG_NUMA */
383 /* zone_start_pfn == zone_start_paddr >> PAGE_SHIFT */
384 unsigned long zone_start_pfn
;
387 * spanned_pages is the total pages spanned by the zone, including
388 * holes, which is calculated as:
389 * spanned_pages = zone_end_pfn - zone_start_pfn;
391 * present_pages is physical pages existing within the zone, which
393 * present_pages = spanned_pages - absent_pages(pages in holes);
395 * managed_pages is present pages managed by the buddy system, which
396 * is calculated as (reserved_pages includes pages allocated by the
397 * bootmem allocator):
398 * managed_pages = present_pages - reserved_pages;
400 * So present_pages may be used by memory hotplug or memory power
401 * management logic to figure out unmanaged pages by checking
402 * (present_pages - managed_pages). And managed_pages should be used
403 * by page allocator and vm scanner to calculate all kinds of watermarks
408 * zone_start_pfn and spanned_pages are protected by span_seqlock.
409 * It is a seqlock because it has to be read outside of zone->lock,
410 * and it is done in the main allocator path. But, it is written
411 * quite infrequently.
413 * The span_seq lock is declared along with zone->lock because it is
414 * frequently read in proximity to zone->lock. It's good to
415 * give them a chance of being in the same cacheline.
417 * Write access to present_pages at runtime should be protected by
418 * mem_hotplug_begin/end(). Any reader who can't tolerant drift of
419 * present_pages should get_online_mems() to get a stable value.
421 * Read access to managed_pages should be safe because it's unsigned
422 * long. Write access to zone->managed_pages and totalram_pages are
423 * protected by managed_page_count_lock at runtime. Idealy only
424 * adjust_managed_page_count() should be used instead of directly
425 * touching zone->managed_pages and totalram_pages.
427 unsigned long managed_pages
;
428 unsigned long spanned_pages
;
429 unsigned long present_pages
;
433 #ifdef CONFIG_MEMORY_ISOLATION
435 * Number of isolated pageblock. It is used to solve incorrect
436 * freepage counting problem due to racy retrieving migratetype
437 * of pageblock. Protected by zone->lock.
439 unsigned long nr_isolate_pageblock
;
442 #ifdef CONFIG_MEMORY_HOTPLUG
443 /* see spanned/present_pages for more description */
444 seqlock_t span_seqlock
;
448 * wait_table -- the array holding the hash table
449 * wait_table_hash_nr_entries -- the size of the hash table array
450 * wait_table_bits -- wait_table_size == (1 << wait_table_bits)
452 * The purpose of all these is to keep track of the people
453 * waiting for a page to become available and make them
454 * runnable again when possible. The trouble is that this
455 * consumes a lot of space, especially when so few things
456 * wait on pages at a given time. So instead of using
457 * per-page waitqueues, we use a waitqueue hash table.
459 * The bucket discipline is to sleep on the same queue when
460 * colliding and wake all in that wait queue when removing.
461 * When something wakes, it must check to be sure its page is
462 * truly available, a la thundering herd. The cost of a
463 * collision is great, but given the expected load of the
464 * table, they should be so rare as to be outweighed by the
465 * benefits from the saved space.
467 * __wait_on_page_locked() and unlock_page() in mm/filemap.c, are the
468 * primary users of these fields, and in mm/page_alloc.c
469 * free_area_init_core() performs the initialization of them.
471 wait_queue_head_t
*wait_table
;
472 unsigned long wait_table_hash_nr_entries
;
473 unsigned long wait_table_bits
;
475 /* Write-intensive fields used from the page allocator */
478 /* free areas of different sizes */
479 struct free_area free_area
[MAX_ORDER
];
481 /* zone flags, see below */
484 /* Primarily protects free_area */
487 /* Write-intensive fields used by compaction and vmstats. */
491 * When free pages are below this point, additional steps are taken
492 * when reading the number of free pages to avoid per-cpu counter
493 * drift allowing watermarks to be breached
495 unsigned long percpu_drift_mark
;
497 #if defined CONFIG_COMPACTION || defined CONFIG_CMA
498 /* pfn where compaction free scanner should start */
499 unsigned long compact_cached_free_pfn
;
500 /* pfn where async and sync compaction migration scanner should start */
501 unsigned long compact_cached_migrate_pfn
[2];
504 #ifdef CONFIG_COMPACTION
506 * On compaction failure, 1<<compact_defer_shift compactions
507 * are skipped before trying again. The number attempted since
508 * last failure is tracked with compact_considered.
510 unsigned int compact_considered
;
511 unsigned int compact_defer_shift
;
512 int compact_order_failed
;
515 #if defined CONFIG_COMPACTION || defined CONFIG_CMA
516 /* Set to true when the PG_migrate_skip bits should be cleared */
517 bool compact_blockskip_flush
;
523 /* Zone statistics */
524 atomic_long_t vm_stat
[NR_VM_ZONE_STAT_ITEMS
];
525 } ____cacheline_internodealigned_in_smp
;
528 ZONE_RECLAIM_LOCKED
, /* prevents concurrent reclaim */
529 ZONE_FAIR_DEPLETED
, /* fair zone policy batch depleted */
533 PGDAT_CONGESTED
, /* pgdat has many dirty pages backed by
536 PGDAT_DIRTY
, /* reclaim scanning has recently found
537 * many dirty file pages at the tail
540 PGDAT_WRITEBACK
, /* reclaim scanning has recently found
541 * many pages under writeback
545 static inline unsigned long zone_end_pfn(const struct zone
*zone
)
547 return zone
->zone_start_pfn
+ zone
->spanned_pages
;
550 static inline bool zone_spans_pfn(const struct zone
*zone
, unsigned long pfn
)
552 return zone
->zone_start_pfn
<= pfn
&& pfn
< zone_end_pfn(zone
);
555 static inline bool zone_is_initialized(struct zone
*zone
)
557 return !!zone
->wait_table
;
560 static inline bool zone_is_empty(struct zone
*zone
)
562 return zone
->spanned_pages
== 0;
566 * The "priority" of VM scanning is how much of the queues we will scan in one
567 * go. A value of 12 for DEF_PRIORITY implies that we will scan 1/4096th of the
568 * queues ("queue_length >> 12") during an aging round.
570 #define DEF_PRIORITY 12
572 /* Maximum number of zones on a zonelist */
573 #define MAX_ZONES_PER_ZONELIST (MAX_NUMNODES * MAX_NR_ZONES)
576 ZONELIST_FALLBACK
, /* zonelist with fallback */
579 * The NUMA zonelists are doubled because we need zonelists that
580 * restrict the allocations to a single node for __GFP_THISNODE.
582 ZONELIST_NOFALLBACK
, /* zonelist without fallback (__GFP_THISNODE) */
588 * This struct contains information about a zone in a zonelist. It is stored
589 * here to avoid dereferences into large structures and lookups of tables
592 struct zone
*zone
; /* Pointer to actual zone */
593 int zone_idx
; /* zone_idx(zoneref->zone) */
597 * One allocation request operates on a zonelist. A zonelist
598 * is a list of zones, the first one is the 'goal' of the
599 * allocation, the other zones are fallback zones, in decreasing
602 * To speed the reading of the zonelist, the zonerefs contain the zone index
603 * of the entry being read. Helper functions to access information given
604 * a struct zoneref are
606 * zonelist_zone() - Return the struct zone * for an entry in _zonerefs
607 * zonelist_zone_idx() - Return the index of the zone for an entry
608 * zonelist_node_idx() - Return the index of the node for an entry
611 struct zoneref _zonerefs
[MAX_ZONES_PER_ZONELIST
+ 1];
614 #ifndef CONFIG_DISCONTIGMEM
615 /* The array of struct pages - for discontigmem use pgdat->lmem_map */
616 extern struct page
*mem_map
;
620 * The pg_data_t structure is used in machines with CONFIG_DISCONTIGMEM
621 * (mostly NUMA machines?) to denote a higher-level memory zone than the
624 * On NUMA machines, each NUMA node would have a pg_data_t to describe
625 * it's memory layout.
627 * Memory statistics and page replacement data structures are maintained on a
631 typedef struct pglist_data
{
632 struct zone node_zones
[MAX_NR_ZONES
];
633 struct zonelist node_zonelists
[MAX_ZONELISTS
];
635 #ifdef CONFIG_FLAT_NODE_MEM_MAP /* means !SPARSEMEM */
636 struct page
*node_mem_map
;
637 #ifdef CONFIG_PAGE_EXTENSION
638 struct page_ext
*node_page_ext
;
641 #ifndef CONFIG_NO_BOOTMEM
642 struct bootmem_data
*bdata
;
644 #ifdef CONFIG_MEMORY_HOTPLUG
646 * Must be held any time you expect node_start_pfn, node_present_pages
647 * or node_spanned_pages stay constant. Holding this will also
648 * guarantee that any pfn_valid() stays that way.
650 * pgdat_resize_lock() and pgdat_resize_unlock() are provided to
651 * manipulate node_size_lock without checking for CONFIG_MEMORY_HOTPLUG.
653 * Nests above zone->lock and zone->span_seqlock
655 spinlock_t node_size_lock
;
657 unsigned long node_start_pfn
;
658 unsigned long node_present_pages
; /* total number of physical pages */
659 unsigned long node_spanned_pages
; /* total size of physical page
660 range, including holes */
662 wait_queue_head_t kswapd_wait
;
663 wait_queue_head_t pfmemalloc_wait
;
664 struct task_struct
*kswapd
; /* Protected by
665 mem_hotplug_begin/end() */
667 enum zone_type kswapd_classzone_idx
;
669 #ifdef CONFIG_COMPACTION
670 int kcompactd_max_order
;
671 enum zone_type kcompactd_classzone_idx
;
672 wait_queue_head_t kcompactd_wait
;
673 struct task_struct
*kcompactd
;
675 #ifdef CONFIG_NUMA_BALANCING
676 /* Lock serializing the migrate rate limiting window */
677 spinlock_t numabalancing_migrate_lock
;
679 /* Rate limiting time interval */
680 unsigned long numabalancing_migrate_next_window
;
682 /* Number of pages migrated during the rate limiting time interval */
683 unsigned long numabalancing_migrate_nr_pages
;
686 * This is a per-node reserve of pages that are not available
687 * to userspace allocations.
689 unsigned long totalreserve_pages
;
691 /* Write-intensive fields used by page reclaim */
695 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
697 * If memory initialisation on large machines is deferred then this
698 * is the first PFN that needs to be initialised.
700 unsigned long first_deferred_pfn
;
701 #endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */
703 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
704 spinlock_t split_queue_lock
;
705 struct list_head split_queue
;
706 unsigned long split_queue_len
;
709 /* Fields commonly accessed by the page reclaim scanner */
710 struct lruvec lruvec
;
713 * The target ratio of ACTIVE_ANON to INACTIVE_ANON pages on
714 * this node's LRU. Maintained by the pageout code.
716 unsigned int inactive_ratio
;
722 /* Per-node vmstats */
723 struct per_cpu_nodestat __percpu
*per_cpu_nodestats
;
724 atomic_long_t vm_stat
[NR_VM_NODE_STAT_ITEMS
];
727 #define node_present_pages(nid) (NODE_DATA(nid)->node_present_pages)
728 #define node_spanned_pages(nid) (NODE_DATA(nid)->node_spanned_pages)
729 #ifdef CONFIG_FLAT_NODE_MEM_MAP
730 #define pgdat_page_nr(pgdat, pagenr) ((pgdat)->node_mem_map + (pagenr))
732 #define pgdat_page_nr(pgdat, pagenr) pfn_to_page((pgdat)->node_start_pfn + (pagenr))
734 #define nid_page_nr(nid, pagenr) pgdat_page_nr(NODE_DATA(nid),(pagenr))
736 #define node_start_pfn(nid) (NODE_DATA(nid)->node_start_pfn)
737 #define node_end_pfn(nid) pgdat_end_pfn(NODE_DATA(nid))
738 static inline spinlock_t
*zone_lru_lock(struct zone
*zone
)
740 return &zone
->zone_pgdat
->lru_lock
;
743 static inline struct lruvec
*node_lruvec(struct pglist_data
*pgdat
)
745 return &pgdat
->lruvec
;
748 static inline unsigned long pgdat_end_pfn(pg_data_t
*pgdat
)
750 return pgdat
->node_start_pfn
+ pgdat
->node_spanned_pages
;
753 static inline bool pgdat_is_empty(pg_data_t
*pgdat
)
755 return !pgdat
->node_start_pfn
&& !pgdat
->node_spanned_pages
;
758 static inline int zone_id(const struct zone
*zone
)
760 struct pglist_data
*pgdat
= zone
->zone_pgdat
;
762 return zone
- pgdat
->node_zones
;
765 #ifdef CONFIG_ZONE_DEVICE
766 static inline bool is_dev_zone(const struct zone
*zone
)
768 return zone_id(zone
) == ZONE_DEVICE
;
771 static inline bool is_dev_zone(const struct zone
*zone
)
777 #include <linux/memory_hotplug.h>
779 extern struct mutex zonelists_mutex
;
780 void build_all_zonelists(pg_data_t
*pgdat
, struct zone
*zone
);
781 void wakeup_kswapd(struct zone
*zone
, int order
, enum zone_type classzone_idx
);
782 bool __zone_watermark_ok(struct zone
*z
, unsigned int order
, unsigned long mark
,
783 int classzone_idx
, unsigned int alloc_flags
,
785 bool zone_watermark_ok(struct zone
*z
, unsigned int order
,
786 unsigned long mark
, int classzone_idx
,
787 unsigned int alloc_flags
);
788 bool zone_watermark_ok_safe(struct zone
*z
, unsigned int order
,
789 unsigned long mark
, int classzone_idx
);
790 enum memmap_context
{
794 extern int init_currently_empty_zone(struct zone
*zone
, unsigned long start_pfn
,
797 extern void lruvec_init(struct lruvec
*lruvec
);
799 static inline struct pglist_data
*lruvec_pgdat(struct lruvec
*lruvec
)
802 return lruvec
->pgdat
;
804 return container_of(lruvec
, struct pglist_data
, lruvec
);
808 extern unsigned long lruvec_lru_size(struct lruvec
*lruvec
, enum lru_list lru
);
810 #ifdef CONFIG_HAVE_MEMORY_PRESENT
811 void memory_present(int nid
, unsigned long start
, unsigned long end
);
813 static inline void memory_present(int nid
, unsigned long start
, unsigned long end
) {}
816 #ifdef CONFIG_HAVE_MEMORYLESS_NODES
817 int local_memory_node(int node_id
);
819 static inline int local_memory_node(int node_id
) { return node_id
; };
822 #ifdef CONFIG_NEED_NODE_MEMMAP_SIZE
823 unsigned long __init
node_memmap_size_bytes(int, unsigned long, unsigned long);
827 * zone_idx() returns 0 for the ZONE_DMA zone, 1 for the ZONE_NORMAL zone, etc.
829 #define zone_idx(zone) ((zone) - (zone)->zone_pgdat->node_zones)
831 static inline int populated_zone(struct zone
*zone
)
833 return (!!zone
->present_pages
);
836 extern int movable_zone
;
838 #ifdef CONFIG_HIGHMEM
839 static inline int zone_movable_is_highmem(void)
841 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
842 return movable_zone
== ZONE_HIGHMEM
;
844 return (ZONE_MOVABLE
- 1) == ZONE_HIGHMEM
;
849 static inline int is_highmem_idx(enum zone_type idx
)
851 #ifdef CONFIG_HIGHMEM
852 return (idx
== ZONE_HIGHMEM
||
853 (idx
== ZONE_MOVABLE
&& zone_movable_is_highmem()));
860 * is_highmem - helper function to quickly check if a struct zone is a
861 * highmem zone or not. This is an attempt to keep references
862 * to ZONE_{DMA/NORMAL/HIGHMEM/etc} in general code to a minimum.
863 * @zone - pointer to struct zone variable
865 static inline int is_highmem(struct zone
*zone
)
867 #ifdef CONFIG_HIGHMEM
868 return is_highmem_idx(zone_idx(zone
));
874 /* These two functions are used to setup the per zone pages min values */
876 int min_free_kbytes_sysctl_handler(struct ctl_table
*, int,
877 void __user
*, size_t *, loff_t
*);
878 int watermark_scale_factor_sysctl_handler(struct ctl_table
*, int,
879 void __user
*, size_t *, loff_t
*);
880 extern int sysctl_lowmem_reserve_ratio
[MAX_NR_ZONES
-1];
881 int lowmem_reserve_ratio_sysctl_handler(struct ctl_table
*, int,
882 void __user
*, size_t *, loff_t
*);
883 int percpu_pagelist_fraction_sysctl_handler(struct ctl_table
*, int,
884 void __user
*, size_t *, loff_t
*);
885 int sysctl_min_unmapped_ratio_sysctl_handler(struct ctl_table
*, int,
886 void __user
*, size_t *, loff_t
*);
887 int sysctl_min_slab_ratio_sysctl_handler(struct ctl_table
*, int,
888 void __user
*, size_t *, loff_t
*);
890 extern int numa_zonelist_order_handler(struct ctl_table
*, int,
891 void __user
*, size_t *, loff_t
*);
892 extern char numa_zonelist_order
[];
893 #define NUMA_ZONELIST_ORDER_LEN 16 /* string buffer size */
895 #ifndef CONFIG_NEED_MULTIPLE_NODES
897 extern struct pglist_data contig_page_data
;
898 #define NODE_DATA(nid) (&contig_page_data)
899 #define NODE_MEM_MAP(nid) mem_map
901 #else /* CONFIG_NEED_MULTIPLE_NODES */
903 #include <asm/mmzone.h>
905 #endif /* !CONFIG_NEED_MULTIPLE_NODES */
907 extern struct pglist_data
*first_online_pgdat(void);
908 extern struct pglist_data
*next_online_pgdat(struct pglist_data
*pgdat
);
909 extern struct zone
*next_zone(struct zone
*zone
);
912 * for_each_online_pgdat - helper macro to iterate over all online nodes
913 * @pgdat - pointer to a pg_data_t variable
915 #define for_each_online_pgdat(pgdat) \
916 for (pgdat = first_online_pgdat(); \
918 pgdat = next_online_pgdat(pgdat))
920 * for_each_zone - helper macro to iterate over all memory zones
921 * @zone - pointer to struct zone variable
923 * The user only needs to declare the zone variable, for_each_zone
926 #define for_each_zone(zone) \
927 for (zone = (first_online_pgdat())->node_zones; \
929 zone = next_zone(zone))
931 #define for_each_populated_zone(zone) \
932 for (zone = (first_online_pgdat())->node_zones; \
934 zone = next_zone(zone)) \
935 if (!populated_zone(zone)) \
939 static inline struct zone
*zonelist_zone(struct zoneref
*zoneref
)
941 return zoneref
->zone
;
944 static inline int zonelist_zone_idx(struct zoneref
*zoneref
)
946 return zoneref
->zone_idx
;
949 static inline int zonelist_node_idx(struct zoneref
*zoneref
)
952 /* zone_to_nid not available in this context */
953 return zoneref
->zone
->node
;
956 #endif /* CONFIG_NUMA */
959 struct zoneref
*__next_zones_zonelist(struct zoneref
*z
,
960 enum zone_type highest_zoneidx
,
964 * 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
965 * @z - The cursor used as a starting point for the search
966 * @highest_zoneidx - The zone index of the highest zone to return
967 * @nodes - An optional nodemask to filter the zonelist with
969 * This function returns the next zone at or below a given zone index that is
970 * within the allowed nodemask using a cursor as the starting point for the
971 * search. The zoneref returned is a cursor that represents the current zone
972 * being examined. It should be advanced by one before calling
973 * next_zones_zonelist again.
975 static __always_inline
struct zoneref
*next_zones_zonelist(struct zoneref
*z
,
976 enum zone_type highest_zoneidx
,
979 if (likely(!nodes
&& zonelist_zone_idx(z
) <= highest_zoneidx
))
981 return __next_zones_zonelist(z
, highest_zoneidx
, nodes
);
985 * first_zones_zonelist - Returns the first zone at or below highest_zoneidx within the allowed nodemask in a zonelist
986 * @zonelist - The zonelist to search for a suitable zone
987 * @highest_zoneidx - The zone index of the highest zone to return
988 * @nodes - An optional nodemask to filter the zonelist with
989 * @zone - The first suitable zone found is returned via this parameter
991 * This function returns the first zone at or below a given zone index that is
992 * within the allowed nodemask. The zoneref returned is a cursor that can be
993 * used to iterate the zonelist with next_zones_zonelist by advancing it by
994 * one before calling.
996 static inline struct zoneref
*first_zones_zonelist(struct zonelist
*zonelist
,
997 enum zone_type highest_zoneidx
,
1000 return next_zones_zonelist(zonelist
->_zonerefs
,
1001 highest_zoneidx
, nodes
);
1005 * 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
1006 * @zone - The current zone in the iterator
1007 * @z - The current pointer within zonelist->zones being iterated
1008 * @zlist - The zonelist being iterated
1009 * @highidx - The zone index of the highest zone to return
1010 * @nodemask - Nodemask allowed by the allocator
1012 * This iterator iterates though all zones at or below a given zone index and
1013 * within a given nodemask
1015 #define for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, nodemask) \
1016 for (z = first_zones_zonelist(zlist, highidx, nodemask), zone = zonelist_zone(z); \
1018 z = next_zones_zonelist(++z, highidx, nodemask), \
1019 zone = zonelist_zone(z))
1021 #define for_next_zone_zonelist_nodemask(zone, z, zlist, highidx, nodemask) \
1022 for (zone = z->zone; \
1024 z = next_zones_zonelist(++z, highidx, nodemask), \
1025 zone = zonelist_zone(z))
1029 * for_each_zone_zonelist - helper macro to iterate over valid zones in a zonelist at or below a given zone index
1030 * @zone - The current zone in the iterator
1031 * @z - The current pointer within zonelist->zones being iterated
1032 * @zlist - The zonelist being iterated
1033 * @highidx - The zone index of the highest zone to return
1035 * This iterator iterates though all zones at or below a given zone index.
1037 #define for_each_zone_zonelist(zone, z, zlist, highidx) \
1038 for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, NULL)
1040 #ifdef CONFIG_SPARSEMEM
1041 #include <asm/sparsemem.h>
1044 #if !defined(CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID) && \
1045 !defined(CONFIG_HAVE_MEMBLOCK_NODE_MAP)
1046 static inline unsigned long early_pfn_to_nid(unsigned long pfn
)
1052 #ifdef CONFIG_FLATMEM
1053 #define pfn_to_nid(pfn) (0)
1056 #ifdef CONFIG_SPARSEMEM
1059 * SECTION_SHIFT #bits space required to store a section #
1061 * PA_SECTION_SHIFT physical address to/from section number
1062 * PFN_SECTION_SHIFT pfn to/from section number
1064 #define PA_SECTION_SHIFT (SECTION_SIZE_BITS)
1065 #define PFN_SECTION_SHIFT (SECTION_SIZE_BITS - PAGE_SHIFT)
1067 #define NR_MEM_SECTIONS (1UL << SECTIONS_SHIFT)
1069 #define PAGES_PER_SECTION (1UL << PFN_SECTION_SHIFT)
1070 #define PAGE_SECTION_MASK (~(PAGES_PER_SECTION-1))
1072 #define SECTION_BLOCKFLAGS_BITS \
1073 ((1UL << (PFN_SECTION_SHIFT - pageblock_order)) * NR_PAGEBLOCK_BITS)
1075 #if (MAX_ORDER - 1 + PAGE_SHIFT) > SECTION_SIZE_BITS
1076 #error Allocator MAX_ORDER exceeds SECTION_SIZE
1079 #define pfn_to_section_nr(pfn) ((pfn) >> PFN_SECTION_SHIFT)
1080 #define section_nr_to_pfn(sec) ((sec) << PFN_SECTION_SHIFT)
1082 #define SECTION_ALIGN_UP(pfn) (((pfn) + PAGES_PER_SECTION - 1) & PAGE_SECTION_MASK)
1083 #define SECTION_ALIGN_DOWN(pfn) ((pfn) & PAGE_SECTION_MASK)
1087 struct mem_section
{
1089 * This is, logically, a pointer to an array of struct
1090 * pages. However, it is stored with some other magic.
1091 * (see sparse.c::sparse_init_one_section())
1093 * Additionally during early boot we encode node id of
1094 * the location of the section here to guide allocation.
1095 * (see sparse.c::memory_present())
1097 * Making it a UL at least makes someone do a cast
1098 * before using it wrong.
1100 unsigned long section_mem_map
;
1102 /* See declaration of similar field in struct zone */
1103 unsigned long *pageblock_flags
;
1104 #ifdef CONFIG_PAGE_EXTENSION
1106 * If SPARSEMEM, pgdat doesn't have page_ext pointer. We use
1107 * section. (see page_ext.h about this.)
1109 struct page_ext
*page_ext
;
1113 * WARNING: mem_section must be a power-of-2 in size for the
1114 * calculation and use of SECTION_ROOT_MASK to make sense.
1118 #ifdef CONFIG_SPARSEMEM_EXTREME
1119 #define SECTIONS_PER_ROOT (PAGE_SIZE / sizeof (struct mem_section))
1121 #define SECTIONS_PER_ROOT 1
1124 #define SECTION_NR_TO_ROOT(sec) ((sec) / SECTIONS_PER_ROOT)
1125 #define NR_SECTION_ROOTS DIV_ROUND_UP(NR_MEM_SECTIONS, SECTIONS_PER_ROOT)
1126 #define SECTION_ROOT_MASK (SECTIONS_PER_ROOT - 1)
1128 #ifdef CONFIG_SPARSEMEM_EXTREME
1129 extern struct mem_section
*mem_section
[NR_SECTION_ROOTS
];
1131 extern struct mem_section mem_section
[NR_SECTION_ROOTS
][SECTIONS_PER_ROOT
];
1134 static inline struct mem_section
*__nr_to_section(unsigned long nr
)
1136 if (!mem_section
[SECTION_NR_TO_ROOT(nr
)])
1138 return &mem_section
[SECTION_NR_TO_ROOT(nr
)][nr
& SECTION_ROOT_MASK
];
1140 extern int __section_nr(struct mem_section
* ms
);
1141 extern unsigned long usemap_size(void);
1144 * We use the lower bits of the mem_map pointer to store
1145 * a little bit of information. There should be at least
1146 * 3 bits here due to 32-bit alignment.
1148 #define SECTION_MARKED_PRESENT (1UL<<0)
1149 #define SECTION_HAS_MEM_MAP (1UL<<1)
1150 #define SECTION_MAP_LAST_BIT (1UL<<2)
1151 #define SECTION_MAP_MASK (~(SECTION_MAP_LAST_BIT-1))
1152 #define SECTION_NID_SHIFT 2
1154 static inline struct page
*__section_mem_map_addr(struct mem_section
*section
)
1156 unsigned long map
= section
->section_mem_map
;
1157 map
&= SECTION_MAP_MASK
;
1158 return (struct page
*)map
;
1161 static inline int present_section(struct mem_section
*section
)
1163 return (section
&& (section
->section_mem_map
& SECTION_MARKED_PRESENT
));
1166 static inline int present_section_nr(unsigned long nr
)
1168 return present_section(__nr_to_section(nr
));
1171 static inline int valid_section(struct mem_section
*section
)
1173 return (section
&& (section
->section_mem_map
& SECTION_HAS_MEM_MAP
));
1176 static inline int valid_section_nr(unsigned long nr
)
1178 return valid_section(__nr_to_section(nr
));
1181 static inline struct mem_section
*__pfn_to_section(unsigned long pfn
)
1183 return __nr_to_section(pfn_to_section_nr(pfn
));
1186 #ifndef CONFIG_HAVE_ARCH_PFN_VALID
1187 static inline int pfn_valid(unsigned long pfn
)
1189 if (pfn_to_section_nr(pfn
) >= NR_MEM_SECTIONS
)
1191 return valid_section(__nr_to_section(pfn_to_section_nr(pfn
)));
1195 static inline int pfn_present(unsigned long pfn
)
1197 if (pfn_to_section_nr(pfn
) >= NR_MEM_SECTIONS
)
1199 return present_section(__nr_to_section(pfn_to_section_nr(pfn
)));
1203 * These are _only_ used during initialisation, therefore they
1204 * can use __initdata ... They could have names to indicate
1208 #define pfn_to_nid(pfn) \
1210 unsigned long __pfn_to_nid_pfn = (pfn); \
1211 page_to_nid(pfn_to_page(__pfn_to_nid_pfn)); \
1214 #define pfn_to_nid(pfn) (0)
1217 #define early_pfn_valid(pfn) pfn_valid(pfn)
1218 void sparse_init(void);
1220 #define sparse_init() do {} while (0)
1221 #define sparse_index_init(_sec, _nid) do {} while (0)
1222 #endif /* CONFIG_SPARSEMEM */
1225 * During memory init memblocks map pfns to nids. The search is expensive and
1226 * this caches recent lookups. The implementation of __early_pfn_to_nid
1227 * may treat start/end as pfns or sections.
1229 struct mminit_pfnnid_cache
{
1230 unsigned long last_start
;
1231 unsigned long last_end
;
1235 #ifndef early_pfn_valid
1236 #define early_pfn_valid(pfn) (1)
1239 void memory_present(int nid
, unsigned long start
, unsigned long end
);
1240 unsigned long __init
node_memmap_size_bytes(int, unsigned long, unsigned long);
1243 * If it is possible to have holes within a MAX_ORDER_NR_PAGES, then we
1244 * need to check pfn validility within that MAX_ORDER_NR_PAGES block.
1245 * pfn_valid_within() should be used in this case; we optimise this away
1246 * when we have no holes within a MAX_ORDER_NR_PAGES block.
1248 #ifdef CONFIG_HOLES_IN_ZONE
1249 #define pfn_valid_within(pfn) pfn_valid(pfn)
1251 #define pfn_valid_within(pfn) (1)
1254 #ifdef CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
1256 * pfn_valid() is meant to be able to tell if a given PFN has valid memmap
1257 * associated with it or not. In FLATMEM, it is expected that holes always
1258 * have valid memmap as long as there is valid PFNs either side of the hole.
1259 * In SPARSEMEM, it is assumed that a valid section has a memmap for the
1262 * However, an ARM, and maybe other embedded architectures in the future
1263 * free memmap backing holes to save memory on the assumption the memmap is
1264 * never used. The page_zone linkages are then broken even though pfn_valid()
1265 * returns true. A walker of the full memmap must then do this additional
1266 * check to ensure the memmap they are looking at is sane by making sure
1267 * the zone and PFN linkages are still valid. This is expensive, but walkers
1268 * of the full memmap are extremely rare.
1270 bool memmap_valid_within(unsigned long pfn
,
1271 struct page
*page
, struct zone
*zone
);
1273 static inline bool memmap_valid_within(unsigned long pfn
,
1274 struct page
*page
, struct zone
*zone
)
1278 #endif /* CONFIG_ARCH_HAS_HOLES_MEMORYMODEL */
1280 #endif /* !__GENERATING_BOUNDS.H */
1281 #endif /* !__ASSEMBLY__ */
1282 #endif /* _LINUX_MMZONE_H */