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)
117 enum zone_stat_item
{
118 /* First 128 byte cacheline (assuming 64 bit words) */
120 NR_ZONE_LRU_BASE
, /* Used only for compaction and reclaim retry */
121 NR_ZONE_INACTIVE_ANON
= NR_ZONE_LRU_BASE
,
123 NR_ZONE_INACTIVE_FILE
,
126 NR_ZONE_WRITE_PENDING
, /* Count of dirty, writeback and unstable pages */
127 NR_MLOCK
, /* mlock()ed pages found and moved off LRU */
128 NR_PAGETABLE
, /* used for pagetables */
129 NR_KERNEL_STACK_KB
, /* measured in KiB */
130 /* Second 128 byte cacheline */
132 #if IS_ENABLED(CONFIG_ZSMALLOC)
133 NR_ZSPAGES
, /* allocated in zsmalloc */
136 NUMA_HIT
, /* allocated in intended node */
137 NUMA_MISS
, /* allocated in non intended node */
138 NUMA_FOREIGN
, /* was intended here, hit elsewhere */
139 NUMA_INTERLEAVE_HIT
, /* interleaver preferred this zone */
140 NUMA_LOCAL
, /* allocation from local node */
141 NUMA_OTHER
, /* allocation from other node */
144 NR_VM_ZONE_STAT_ITEMS
};
146 enum node_stat_item
{
148 NR_INACTIVE_ANON
= NR_LRU_BASE
, /* must match order of LRU_[IN]ACTIVE */
149 NR_ACTIVE_ANON
, /* " " " " " */
150 NR_INACTIVE_FILE
, /* " " " " " */
151 NR_ACTIVE_FILE
, /* " " " " " */
152 NR_UNEVICTABLE
, /* " " " " " */
154 NR_SLAB_UNRECLAIMABLE
,
155 NR_ISOLATED_ANON
, /* Temporary isolated pages from anon lru */
156 NR_ISOLATED_FILE
, /* Temporary isolated pages from file lru */
159 WORKINGSET_NODERECLAIM
,
160 NR_ANON_MAPPED
, /* Mapped anonymous pages */
161 NR_FILE_MAPPED
, /* pagecache pages mapped into pagetables.
162 only modified from process context */
166 NR_WRITEBACK_TEMP
, /* Writeback using temporary buffers */
167 NR_SHMEM
, /* shmem pages (included tmpfs/GEM pages) */
171 NR_UNSTABLE_NFS
, /* NFS unstable pages */
173 NR_VMSCAN_IMMEDIATE
, /* Prioritise for reclaim when writeback ends */
174 NR_DIRTIED
, /* page dirtyings since bootup */
175 NR_WRITTEN
, /* page writings since bootup */
176 NR_VM_NODE_STAT_ITEMS
180 * We do arithmetic on the LRU lists in various places in the code,
181 * so it is important to keep the active lists LRU_ACTIVE higher in
182 * the array than the corresponding inactive lists, and to keep
183 * the *_FILE lists LRU_FILE higher than the corresponding _ANON lists.
185 * This has to be kept in sync with the statistics in zone_stat_item
186 * above and the descriptions in vmstat_text in mm/vmstat.c
193 LRU_INACTIVE_ANON
= LRU_BASE
,
194 LRU_ACTIVE_ANON
= LRU_BASE
+ LRU_ACTIVE
,
195 LRU_INACTIVE_FILE
= LRU_BASE
+ LRU_FILE
,
196 LRU_ACTIVE_FILE
= LRU_BASE
+ LRU_FILE
+ LRU_ACTIVE
,
201 #define for_each_lru(lru) for (lru = 0; lru < NR_LRU_LISTS; lru++)
203 #define for_each_evictable_lru(lru) for (lru = 0; lru <= LRU_ACTIVE_FILE; lru++)
205 static inline int is_file_lru(enum lru_list lru
)
207 return (lru
== LRU_INACTIVE_FILE
|| lru
== LRU_ACTIVE_FILE
);
210 static inline int is_active_lru(enum lru_list lru
)
212 return (lru
== LRU_ACTIVE_ANON
|| lru
== LRU_ACTIVE_FILE
);
215 struct zone_reclaim_stat
{
217 * The pageout code in vmscan.c keeps track of how many of the
218 * mem/swap backed and file backed pages are referenced.
219 * The higher the rotated/scanned ratio, the more valuable
222 * The anon LRU stats live in [0], file LRU stats in [1]
224 unsigned long recent_rotated
[2];
225 unsigned long recent_scanned
[2];
229 struct list_head lists
[NR_LRU_LISTS
];
230 struct zone_reclaim_stat reclaim_stat
;
231 /* Evictions & activations on the inactive file list */
232 atomic_long_t inactive_age
;
233 /* Refaults at the time of last reclaim cycle */
234 unsigned long refaults
;
236 struct pglist_data
*pgdat
;
240 /* Mask used at gathering information at once (see memcontrol.c) */
241 #define LRU_ALL_FILE (BIT(LRU_INACTIVE_FILE) | BIT(LRU_ACTIVE_FILE))
242 #define LRU_ALL_ANON (BIT(LRU_INACTIVE_ANON) | BIT(LRU_ACTIVE_ANON))
243 #define LRU_ALL ((1 << NR_LRU_LISTS) - 1)
245 /* Isolate unmapped file */
246 #define ISOLATE_UNMAPPED ((__force isolate_mode_t)0x2)
247 /* Isolate for asynchronous migration */
248 #define ISOLATE_ASYNC_MIGRATE ((__force isolate_mode_t)0x4)
249 /* Isolate unevictable pages */
250 #define ISOLATE_UNEVICTABLE ((__force isolate_mode_t)0x8)
252 /* LRU Isolation modes. */
253 typedef unsigned __bitwise isolate_mode_t
;
255 enum zone_watermarks
{
262 #define min_wmark_pages(z) (z->watermark[WMARK_MIN])
263 #define low_wmark_pages(z) (z->watermark[WMARK_LOW])
264 #define high_wmark_pages(z) (z->watermark[WMARK_HIGH])
266 struct per_cpu_pages
{
267 int count
; /* number of pages in the list */
268 int high
; /* high watermark, emptying needed */
269 int batch
; /* chunk size for buddy add/remove */
271 /* Lists of pages, one per migrate type stored on the pcp-lists */
272 struct list_head lists
[MIGRATE_PCPTYPES
];
275 struct per_cpu_pageset
{
276 struct per_cpu_pages pcp
;
282 s8 vm_stat_diff
[NR_VM_ZONE_STAT_ITEMS
];
286 struct per_cpu_nodestat
{
288 s8 vm_node_stat_diff
[NR_VM_NODE_STAT_ITEMS
];
291 #endif /* !__GENERATING_BOUNDS.H */
294 #ifdef CONFIG_ZONE_DMA
296 * ZONE_DMA is used when there are devices that are not able
297 * to do DMA to all of addressable memory (ZONE_NORMAL). Then we
298 * carve out the portion of memory that is needed for these devices.
299 * The range is arch specific.
304 * ---------------------------
305 * parisc, ia64, sparc <4G
308 * alpha Unlimited or 0-16MB.
310 * i386, x86_64 and multiple other arches
315 #ifdef CONFIG_ZONE_DMA32
317 * x86_64 needs two ZONE_DMAs because it supports devices that are
318 * only able to do DMA to the lower 16M but also 32 bit devices that
319 * can only do DMA areas below 4G.
324 * Normal addressable memory is in ZONE_NORMAL. DMA operations can be
325 * performed on pages in ZONE_NORMAL if the DMA devices support
326 * transfers to all addressable memory.
329 #ifdef CONFIG_HIGHMEM
331 * A memory area that is only addressable by the kernel through
332 * mapping portions into its own address space. This is for example
333 * used by i386 to allow the kernel to address the memory beyond
334 * 900MB. The kernel will set up special mappings (page
335 * table entries on i386) for each page that the kernel needs to
341 #ifdef CONFIG_ZONE_DEVICE
348 #ifndef __GENERATING_BOUNDS_H
351 /* Read-mostly fields */
353 /* zone watermarks, access with *_wmark_pages(zone) macros */
354 unsigned long watermark
[NR_WMARK
];
356 unsigned long nr_reserved_highatomic
;
359 * We don't know if the memory that we're going to allocate will be
360 * freeable or/and it will be released eventually, so to avoid totally
361 * wasting several GB of ram we must reserve some of the lower zone
362 * memory (otherwise we risk to run OOM on the lower zones despite
363 * there being tons of freeable ram on the higher zones). This array is
364 * recalculated at runtime if the sysctl_lowmem_reserve_ratio sysctl
367 long lowmem_reserve
[MAX_NR_ZONES
];
372 struct pglist_data
*zone_pgdat
;
373 struct per_cpu_pageset __percpu
*pageset
;
375 #ifndef CONFIG_SPARSEMEM
377 * Flags for a pageblock_nr_pages block. See pageblock-flags.h.
378 * In SPARSEMEM, this map is stored in struct mem_section
380 unsigned long *pageblock_flags
;
381 #endif /* CONFIG_SPARSEMEM */
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
;
449 /* Write-intensive fields used from the page allocator */
452 /* free areas of different sizes */
453 struct free_area free_area
[MAX_ORDER
];
455 /* zone flags, see below */
458 /* Primarily protects free_area */
461 /* Write-intensive fields used by compaction and vmstats. */
465 * When free pages are below this point, additional steps are taken
466 * when reading the number of free pages to avoid per-cpu counter
467 * drift allowing watermarks to be breached
469 unsigned long percpu_drift_mark
;
471 #if defined CONFIG_COMPACTION || defined CONFIG_CMA
472 /* pfn where compaction free scanner should start */
473 unsigned long compact_cached_free_pfn
;
474 /* pfn where async and sync compaction migration scanner should start */
475 unsigned long compact_cached_migrate_pfn
[2];
478 #ifdef CONFIG_COMPACTION
480 * On compaction failure, 1<<compact_defer_shift compactions
481 * are skipped before trying again. The number attempted since
482 * last failure is tracked with compact_considered.
484 unsigned int compact_considered
;
485 unsigned int compact_defer_shift
;
486 int compact_order_failed
;
489 #if defined CONFIG_COMPACTION || defined CONFIG_CMA
490 /* Set to true when the PG_migrate_skip bits should be cleared */
491 bool compact_blockskip_flush
;
497 /* Zone statistics */
498 atomic_long_t vm_stat
[NR_VM_ZONE_STAT_ITEMS
];
499 } ____cacheline_internodealigned_in_smp
;
502 PGDAT_CONGESTED
, /* pgdat has many dirty pages backed by
505 PGDAT_DIRTY
, /* reclaim scanning has recently found
506 * many dirty file pages at the tail
509 PGDAT_WRITEBACK
, /* reclaim scanning has recently found
510 * many pages under writeback
512 PGDAT_RECLAIM_LOCKED
, /* prevents concurrent reclaim */
515 static inline unsigned long zone_end_pfn(const struct zone
*zone
)
517 return zone
->zone_start_pfn
+ zone
->spanned_pages
;
520 static inline bool zone_spans_pfn(const struct zone
*zone
, unsigned long pfn
)
522 return zone
->zone_start_pfn
<= pfn
&& pfn
< zone_end_pfn(zone
);
525 static inline bool zone_is_initialized(struct zone
*zone
)
527 return zone
->initialized
;
530 static inline bool zone_is_empty(struct zone
*zone
)
532 return zone
->spanned_pages
== 0;
536 * Return true if [start_pfn, start_pfn + nr_pages) range has a non-empty
537 * intersection with the given zone
539 static inline bool zone_intersects(struct zone
*zone
,
540 unsigned long start_pfn
, unsigned long nr_pages
)
542 if (zone_is_empty(zone
))
544 if (start_pfn
>= zone_end_pfn(zone
) ||
545 start_pfn
+ nr_pages
<= zone
->zone_start_pfn
)
552 * The "priority" of VM scanning is how much of the queues we will scan in one
553 * go. A value of 12 for DEF_PRIORITY implies that we will scan 1/4096th of the
554 * queues ("queue_length >> 12") during an aging round.
556 #define DEF_PRIORITY 12
558 /* Maximum number of zones on a zonelist */
559 #define MAX_ZONES_PER_ZONELIST (MAX_NUMNODES * MAX_NR_ZONES)
562 ZONELIST_FALLBACK
, /* zonelist with fallback */
565 * The NUMA zonelists are doubled because we need zonelists that
566 * restrict the allocations to a single node for __GFP_THISNODE.
568 ZONELIST_NOFALLBACK
, /* zonelist without fallback (__GFP_THISNODE) */
574 * This struct contains information about a zone in a zonelist. It is stored
575 * here to avoid dereferences into large structures and lookups of tables
578 struct zone
*zone
; /* Pointer to actual zone */
579 int zone_idx
; /* zone_idx(zoneref->zone) */
583 * One allocation request operates on a zonelist. A zonelist
584 * is a list of zones, the first one is the 'goal' of the
585 * allocation, the other zones are fallback zones, in decreasing
588 * To speed the reading of the zonelist, the zonerefs contain the zone index
589 * of the entry being read. Helper functions to access information given
590 * a struct zoneref are
592 * zonelist_zone() - Return the struct zone * for an entry in _zonerefs
593 * zonelist_zone_idx() - Return the index of the zone for an entry
594 * zonelist_node_idx() - Return the index of the node for an entry
597 struct zoneref _zonerefs
[MAX_ZONES_PER_ZONELIST
+ 1];
600 #ifndef CONFIG_DISCONTIGMEM
601 /* The array of struct pages - for discontigmem use pgdat->lmem_map */
602 extern struct page
*mem_map
;
606 * On NUMA machines, each NUMA node would have a pg_data_t to describe
607 * it's memory layout. On UMA machines there is a single pglist_data which
608 * describes the whole memory.
610 * Memory statistics and page replacement data structures are maintained on a
614 typedef struct pglist_data
{
615 struct zone node_zones
[MAX_NR_ZONES
];
616 struct zonelist node_zonelists
[MAX_ZONELISTS
];
618 #ifdef CONFIG_FLAT_NODE_MEM_MAP /* means !SPARSEMEM */
619 struct page
*node_mem_map
;
620 #ifdef CONFIG_PAGE_EXTENSION
621 struct page_ext
*node_page_ext
;
624 #ifndef CONFIG_NO_BOOTMEM
625 struct bootmem_data
*bdata
;
627 #ifdef CONFIG_MEMORY_HOTPLUG
629 * Must be held any time you expect node_start_pfn, node_present_pages
630 * or node_spanned_pages stay constant. Holding this will also
631 * guarantee that any pfn_valid() stays that way.
633 * pgdat_resize_lock() and pgdat_resize_unlock() are provided to
634 * manipulate node_size_lock without checking for CONFIG_MEMORY_HOTPLUG.
636 * Nests above zone->lock and zone->span_seqlock
638 spinlock_t node_size_lock
;
640 unsigned long node_start_pfn
;
641 unsigned long node_present_pages
; /* total number of physical pages */
642 unsigned long node_spanned_pages
; /* total size of physical page
643 range, including holes */
645 wait_queue_head_t kswapd_wait
;
646 wait_queue_head_t pfmemalloc_wait
;
647 struct task_struct
*kswapd
; /* Protected by
648 mem_hotplug_begin/end() */
650 enum zone_type kswapd_classzone_idx
;
652 int kswapd_failures
; /* Number of 'reclaimed == 0' runs */
654 #ifdef CONFIG_COMPACTION
655 int kcompactd_max_order
;
656 enum zone_type kcompactd_classzone_idx
;
657 wait_queue_head_t kcompactd_wait
;
658 struct task_struct
*kcompactd
;
660 #ifdef CONFIG_NUMA_BALANCING
661 /* Lock serializing the migrate rate limiting window */
662 spinlock_t numabalancing_migrate_lock
;
664 /* Rate limiting time interval */
665 unsigned long numabalancing_migrate_next_window
;
667 /* Number of pages migrated during the rate limiting time interval */
668 unsigned long numabalancing_migrate_nr_pages
;
671 * This is a per-node reserve of pages that are not available
672 * to userspace allocations.
674 unsigned long totalreserve_pages
;
678 * zone reclaim becomes active if more unmapped pages exist.
680 unsigned long min_unmapped_pages
;
681 unsigned long min_slab_pages
;
682 #endif /* CONFIG_NUMA */
684 /* Write-intensive fields used by page reclaim */
688 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
690 * If memory initialisation on large machines is deferred then this
691 * is the first PFN that needs to be initialised.
693 unsigned long first_deferred_pfn
;
694 unsigned long static_init_size
;
695 #endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */
697 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
698 spinlock_t split_queue_lock
;
699 struct list_head split_queue
;
700 unsigned long split_queue_len
;
703 /* Fields commonly accessed by the page reclaim scanner */
704 struct lruvec lruvec
;
707 * The target ratio of ACTIVE_ANON to INACTIVE_ANON pages on
708 * this node's LRU. Maintained by the pageout code.
710 unsigned int inactive_ratio
;
716 /* Per-node vmstats */
717 struct per_cpu_nodestat __percpu
*per_cpu_nodestats
;
718 atomic_long_t vm_stat
[NR_VM_NODE_STAT_ITEMS
];
721 #define node_present_pages(nid) (NODE_DATA(nid)->node_present_pages)
722 #define node_spanned_pages(nid) (NODE_DATA(nid)->node_spanned_pages)
723 #ifdef CONFIG_FLAT_NODE_MEM_MAP
724 #define pgdat_page_nr(pgdat, pagenr) ((pgdat)->node_mem_map + (pagenr))
726 #define pgdat_page_nr(pgdat, pagenr) pfn_to_page((pgdat)->node_start_pfn + (pagenr))
728 #define nid_page_nr(nid, pagenr) pgdat_page_nr(NODE_DATA(nid),(pagenr))
730 #define node_start_pfn(nid) (NODE_DATA(nid)->node_start_pfn)
731 #define node_end_pfn(nid) pgdat_end_pfn(NODE_DATA(nid))
732 static inline spinlock_t
*zone_lru_lock(struct zone
*zone
)
734 return &zone
->zone_pgdat
->lru_lock
;
737 static inline struct lruvec
*node_lruvec(struct pglist_data
*pgdat
)
739 return &pgdat
->lruvec
;
742 static inline unsigned long pgdat_end_pfn(pg_data_t
*pgdat
)
744 return pgdat
->node_start_pfn
+ pgdat
->node_spanned_pages
;
747 static inline bool pgdat_is_empty(pg_data_t
*pgdat
)
749 return !pgdat
->node_start_pfn
&& !pgdat
->node_spanned_pages
;
752 static inline int zone_id(const struct zone
*zone
)
754 struct pglist_data
*pgdat
= zone
->zone_pgdat
;
756 return zone
- pgdat
->node_zones
;
759 #ifdef CONFIG_ZONE_DEVICE
760 static inline bool is_dev_zone(const struct zone
*zone
)
762 return zone_id(zone
) == ZONE_DEVICE
;
765 static inline bool is_dev_zone(const struct zone
*zone
)
771 #include <linux/memory_hotplug.h>
773 extern struct mutex zonelists_mutex
;
774 void build_all_zonelists(pg_data_t
*pgdat
, struct zone
*zone
);
775 void wakeup_kswapd(struct zone
*zone
, int order
, enum zone_type classzone_idx
);
776 bool __zone_watermark_ok(struct zone
*z
, unsigned int order
, unsigned long mark
,
777 int classzone_idx
, unsigned int alloc_flags
,
779 bool zone_watermark_ok(struct zone
*z
, unsigned int order
,
780 unsigned long mark
, int classzone_idx
,
781 unsigned int alloc_flags
);
782 bool zone_watermark_ok_safe(struct zone
*z
, unsigned int order
,
783 unsigned long mark
, int classzone_idx
);
784 enum memmap_context
{
788 extern void init_currently_empty_zone(struct zone
*zone
, unsigned long start_pfn
,
791 extern void lruvec_init(struct lruvec
*lruvec
);
793 static inline struct pglist_data
*lruvec_pgdat(struct lruvec
*lruvec
)
796 return lruvec
->pgdat
;
798 return container_of(lruvec
, struct pglist_data
, lruvec
);
802 extern unsigned long lruvec_lru_size(struct lruvec
*lruvec
, enum lru_list lru
, int zone_idx
);
804 #ifdef CONFIG_HAVE_MEMORY_PRESENT
805 void memory_present(int nid
, unsigned long start
, unsigned long end
);
807 static inline void memory_present(int nid
, unsigned long start
, unsigned long end
) {}
810 #ifdef CONFIG_HAVE_MEMORYLESS_NODES
811 int local_memory_node(int node_id
);
813 static inline int local_memory_node(int node_id
) { return node_id
; };
816 #ifdef CONFIG_NEED_NODE_MEMMAP_SIZE
817 unsigned long __init
node_memmap_size_bytes(int, unsigned long, unsigned long);
821 * zone_idx() returns 0 for the ZONE_DMA zone, 1 for the ZONE_NORMAL zone, etc.
823 #define zone_idx(zone) ((zone) - (zone)->zone_pgdat->node_zones)
826 * Returns true if a zone has pages managed by the buddy allocator.
827 * All the reclaim decisions have to use this function rather than
828 * populated_zone(). If the whole zone is reserved then we can easily
829 * end up with populated_zone() && !managed_zone().
831 static inline bool managed_zone(struct zone
*zone
)
833 return zone
->managed_pages
;
836 /* Returns true if a zone has memory */
837 static inline bool populated_zone(struct zone
*zone
)
839 return zone
->present_pages
;
842 extern int movable_zone
;
844 #ifdef CONFIG_HIGHMEM
845 static inline int zone_movable_is_highmem(void)
847 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
848 return movable_zone
== ZONE_HIGHMEM
;
850 return (ZONE_MOVABLE
- 1) == ZONE_HIGHMEM
;
855 static inline int is_highmem_idx(enum zone_type idx
)
857 #ifdef CONFIG_HIGHMEM
858 return (idx
== ZONE_HIGHMEM
||
859 (idx
== ZONE_MOVABLE
&& zone_movable_is_highmem()));
866 * is_highmem - helper function to quickly check if a struct zone is a
867 * highmem zone or not. This is an attempt to keep references
868 * to ZONE_{DMA/NORMAL/HIGHMEM/etc} in general code to a minimum.
869 * @zone - pointer to struct zone variable
871 static inline int is_highmem(struct zone
*zone
)
873 #ifdef CONFIG_HIGHMEM
874 return is_highmem_idx(zone_idx(zone
));
880 /* These two functions are used to setup the per zone pages min values */
882 int min_free_kbytes_sysctl_handler(struct ctl_table
*, int,
883 void __user
*, size_t *, loff_t
*);
884 int watermark_scale_factor_sysctl_handler(struct ctl_table
*, int,
885 void __user
*, size_t *, loff_t
*);
886 extern int sysctl_lowmem_reserve_ratio
[MAX_NR_ZONES
-1];
887 int lowmem_reserve_ratio_sysctl_handler(struct ctl_table
*, int,
888 void __user
*, size_t *, loff_t
*);
889 int percpu_pagelist_fraction_sysctl_handler(struct ctl_table
*, int,
890 void __user
*, size_t *, loff_t
*);
891 int sysctl_min_unmapped_ratio_sysctl_handler(struct ctl_table
*, int,
892 void __user
*, size_t *, loff_t
*);
893 int sysctl_min_slab_ratio_sysctl_handler(struct ctl_table
*, int,
894 void __user
*, size_t *, loff_t
*);
896 extern int numa_zonelist_order_handler(struct ctl_table
*, int,
897 void __user
*, size_t *, loff_t
*);
898 extern char numa_zonelist_order
[];
899 #define NUMA_ZONELIST_ORDER_LEN 16 /* string buffer size */
901 #ifndef CONFIG_NEED_MULTIPLE_NODES
903 extern struct pglist_data contig_page_data
;
904 #define NODE_DATA(nid) (&contig_page_data)
905 #define NODE_MEM_MAP(nid) mem_map
907 #else /* CONFIG_NEED_MULTIPLE_NODES */
909 #include <asm/mmzone.h>
911 #endif /* !CONFIG_NEED_MULTIPLE_NODES */
913 extern struct pglist_data
*first_online_pgdat(void);
914 extern struct pglist_data
*next_online_pgdat(struct pglist_data
*pgdat
);
915 extern struct zone
*next_zone(struct zone
*zone
);
918 * for_each_online_pgdat - helper macro to iterate over all online nodes
919 * @pgdat - pointer to a pg_data_t variable
921 #define for_each_online_pgdat(pgdat) \
922 for (pgdat = first_online_pgdat(); \
924 pgdat = next_online_pgdat(pgdat))
926 * for_each_zone - helper macro to iterate over all memory zones
927 * @zone - pointer to struct zone variable
929 * The user only needs to declare the zone variable, for_each_zone
932 #define for_each_zone(zone) \
933 for (zone = (first_online_pgdat())->node_zones; \
935 zone = next_zone(zone))
937 #define for_each_populated_zone(zone) \
938 for (zone = (first_online_pgdat())->node_zones; \
940 zone = next_zone(zone)) \
941 if (!populated_zone(zone)) \
945 static inline struct zone
*zonelist_zone(struct zoneref
*zoneref
)
947 return zoneref
->zone
;
950 static inline int zonelist_zone_idx(struct zoneref
*zoneref
)
952 return zoneref
->zone_idx
;
955 static inline int zonelist_node_idx(struct zoneref
*zoneref
)
958 /* zone_to_nid not available in this context */
959 return zoneref
->zone
->node
;
962 #endif /* CONFIG_NUMA */
965 struct zoneref
*__next_zones_zonelist(struct zoneref
*z
,
966 enum zone_type highest_zoneidx
,
970 * 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
971 * @z - The cursor used as a starting point for the search
972 * @highest_zoneidx - The zone index of the highest zone to return
973 * @nodes - An optional nodemask to filter the zonelist with
975 * This function returns the next zone at or below a given zone index that is
976 * within the allowed nodemask using a cursor as the starting point for the
977 * search. The zoneref returned is a cursor that represents the current zone
978 * being examined. It should be advanced by one before calling
979 * next_zones_zonelist again.
981 static __always_inline
struct zoneref
*next_zones_zonelist(struct zoneref
*z
,
982 enum zone_type highest_zoneidx
,
985 if (likely(!nodes
&& zonelist_zone_idx(z
) <= highest_zoneidx
))
987 return __next_zones_zonelist(z
, highest_zoneidx
, nodes
);
991 * first_zones_zonelist - Returns the first zone at or below highest_zoneidx within the allowed nodemask in a zonelist
992 * @zonelist - The zonelist to search for a suitable zone
993 * @highest_zoneidx - The zone index of the highest zone to return
994 * @nodes - An optional nodemask to filter the zonelist with
995 * @return - Zoneref pointer for the first suitable zone found (see below)
997 * This function returns the first zone at or below a given zone index that is
998 * within the allowed nodemask. The zoneref returned is a cursor that can be
999 * used to iterate the zonelist with next_zones_zonelist by advancing it by
1000 * one before calling.
1002 * When no eligible zone is found, zoneref->zone is NULL (zoneref itself is
1003 * never NULL). This may happen either genuinely, or due to concurrent nodemask
1004 * update due to cpuset modification.
1006 static inline struct zoneref
*first_zones_zonelist(struct zonelist
*zonelist
,
1007 enum zone_type highest_zoneidx
,
1010 return next_zones_zonelist(zonelist
->_zonerefs
,
1011 highest_zoneidx
, nodes
);
1015 * 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
1016 * @zone - The current zone in the iterator
1017 * @z - The current pointer within zonelist->zones being iterated
1018 * @zlist - The zonelist being iterated
1019 * @highidx - The zone index of the highest zone to return
1020 * @nodemask - Nodemask allowed by the allocator
1022 * This iterator iterates though all zones at or below a given zone index and
1023 * within a given nodemask
1025 #define for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, nodemask) \
1026 for (z = first_zones_zonelist(zlist, highidx, nodemask), zone = zonelist_zone(z); \
1028 z = next_zones_zonelist(++z, highidx, nodemask), \
1029 zone = zonelist_zone(z))
1031 #define for_next_zone_zonelist_nodemask(zone, z, zlist, highidx, nodemask) \
1032 for (zone = z->zone; \
1034 z = next_zones_zonelist(++z, highidx, nodemask), \
1035 zone = zonelist_zone(z))
1039 * for_each_zone_zonelist - helper macro to iterate over valid zones in a zonelist at or below a given zone index
1040 * @zone - The current zone in the iterator
1041 * @z - The current pointer within zonelist->zones being iterated
1042 * @zlist - The zonelist being iterated
1043 * @highidx - The zone index of the highest zone to return
1045 * This iterator iterates though all zones at or below a given zone index.
1047 #define for_each_zone_zonelist(zone, z, zlist, highidx) \
1048 for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, NULL)
1050 #ifdef CONFIG_SPARSEMEM
1051 #include <asm/sparsemem.h>
1054 #if !defined(CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID) && \
1055 !defined(CONFIG_HAVE_MEMBLOCK_NODE_MAP)
1056 static inline unsigned long early_pfn_to_nid(unsigned long pfn
)
1058 BUILD_BUG_ON(IS_ENABLED(CONFIG_NUMA
));
1063 #ifdef CONFIG_FLATMEM
1064 #define pfn_to_nid(pfn) (0)
1067 #ifdef CONFIG_SPARSEMEM
1070 * SECTION_SHIFT #bits space required to store a section #
1072 * PA_SECTION_SHIFT physical address to/from section number
1073 * PFN_SECTION_SHIFT pfn to/from section number
1075 #define PA_SECTION_SHIFT (SECTION_SIZE_BITS)
1076 #define PFN_SECTION_SHIFT (SECTION_SIZE_BITS - PAGE_SHIFT)
1078 #define NR_MEM_SECTIONS (1UL << SECTIONS_SHIFT)
1080 #define PAGES_PER_SECTION (1UL << PFN_SECTION_SHIFT)
1081 #define PAGE_SECTION_MASK (~(PAGES_PER_SECTION-1))
1083 #define SECTION_BLOCKFLAGS_BITS \
1084 ((1UL << (PFN_SECTION_SHIFT - pageblock_order)) * NR_PAGEBLOCK_BITS)
1086 #if (MAX_ORDER - 1 + PAGE_SHIFT) > SECTION_SIZE_BITS
1087 #error Allocator MAX_ORDER exceeds SECTION_SIZE
1090 #define pfn_to_section_nr(pfn) ((pfn) >> PFN_SECTION_SHIFT)
1091 #define section_nr_to_pfn(sec) ((sec) << PFN_SECTION_SHIFT)
1093 #define SECTION_ALIGN_UP(pfn) (((pfn) + PAGES_PER_SECTION - 1) & PAGE_SECTION_MASK)
1094 #define SECTION_ALIGN_DOWN(pfn) ((pfn) & PAGE_SECTION_MASK)
1098 struct mem_section
{
1100 * This is, logically, a pointer to an array of struct
1101 * pages. However, it is stored with some other magic.
1102 * (see sparse.c::sparse_init_one_section())
1104 * Additionally during early boot we encode node id of
1105 * the location of the section here to guide allocation.
1106 * (see sparse.c::memory_present())
1108 * Making it a UL at least makes someone do a cast
1109 * before using it wrong.
1111 unsigned long section_mem_map
;
1113 /* See declaration of similar field in struct zone */
1114 unsigned long *pageblock_flags
;
1115 #ifdef CONFIG_PAGE_EXTENSION
1117 * If SPARSEMEM, pgdat doesn't have page_ext pointer. We use
1118 * section. (see page_ext.h about this.)
1120 struct page_ext
*page_ext
;
1124 * WARNING: mem_section must be a power-of-2 in size for the
1125 * calculation and use of SECTION_ROOT_MASK to make sense.
1129 #ifdef CONFIG_SPARSEMEM_EXTREME
1130 #define SECTIONS_PER_ROOT (PAGE_SIZE / sizeof (struct mem_section))
1132 #define SECTIONS_PER_ROOT 1
1135 #define SECTION_NR_TO_ROOT(sec) ((sec) / SECTIONS_PER_ROOT)
1136 #define NR_SECTION_ROOTS DIV_ROUND_UP(NR_MEM_SECTIONS, SECTIONS_PER_ROOT)
1137 #define SECTION_ROOT_MASK (SECTIONS_PER_ROOT - 1)
1139 #ifdef CONFIG_SPARSEMEM_EXTREME
1140 extern struct mem_section
*mem_section
[NR_SECTION_ROOTS
];
1142 extern struct mem_section mem_section
[NR_SECTION_ROOTS
][SECTIONS_PER_ROOT
];
1145 static inline struct mem_section
*__nr_to_section(unsigned long nr
)
1147 if (!mem_section
[SECTION_NR_TO_ROOT(nr
)])
1149 return &mem_section
[SECTION_NR_TO_ROOT(nr
)][nr
& SECTION_ROOT_MASK
];
1151 extern int __section_nr(struct mem_section
* ms
);
1152 extern unsigned long usemap_size(void);
1155 * We use the lower bits of the mem_map pointer to store
1156 * a little bit of information. There should be at least
1157 * 3 bits here due to 32-bit alignment.
1159 #define SECTION_MARKED_PRESENT (1UL<<0)
1160 #define SECTION_HAS_MEM_MAP (1UL<<1)
1161 #define SECTION_IS_ONLINE (1UL<<2)
1162 #define SECTION_MAP_LAST_BIT (1UL<<3)
1163 #define SECTION_MAP_MASK (~(SECTION_MAP_LAST_BIT-1))
1164 #define SECTION_NID_SHIFT 3
1166 static inline struct page
*__section_mem_map_addr(struct mem_section
*section
)
1168 unsigned long map
= section
->section_mem_map
;
1169 map
&= SECTION_MAP_MASK
;
1170 return (struct page
*)map
;
1173 static inline int present_section(struct mem_section
*section
)
1175 return (section
&& (section
->section_mem_map
& SECTION_MARKED_PRESENT
));
1178 static inline int present_section_nr(unsigned long nr
)
1180 return present_section(__nr_to_section(nr
));
1183 static inline int valid_section(struct mem_section
*section
)
1185 return (section
&& (section
->section_mem_map
& SECTION_HAS_MEM_MAP
));
1188 static inline int valid_section_nr(unsigned long nr
)
1190 return valid_section(__nr_to_section(nr
));
1193 static inline int online_section(struct mem_section
*section
)
1195 return (section
&& (section
->section_mem_map
& SECTION_IS_ONLINE
));
1198 static inline int online_section_nr(unsigned long nr
)
1200 return online_section(__nr_to_section(nr
));
1203 #ifdef CONFIG_MEMORY_HOTPLUG
1204 void online_mem_sections(unsigned long start_pfn
, unsigned long end_pfn
);
1205 #ifdef CONFIG_MEMORY_HOTREMOVE
1206 void offline_mem_sections(unsigned long start_pfn
, unsigned long end_pfn
);
1210 static inline struct mem_section
*__pfn_to_section(unsigned long pfn
)
1212 return __nr_to_section(pfn_to_section_nr(pfn
));
1215 extern int __highest_present_section_nr
;
1217 #ifndef CONFIG_HAVE_ARCH_PFN_VALID
1218 static inline int pfn_valid(unsigned long pfn
)
1220 if (pfn_to_section_nr(pfn
) >= NR_MEM_SECTIONS
)
1222 return valid_section(__nr_to_section(pfn_to_section_nr(pfn
)));
1226 static inline int pfn_present(unsigned long pfn
)
1228 if (pfn_to_section_nr(pfn
) >= NR_MEM_SECTIONS
)
1230 return present_section(__nr_to_section(pfn_to_section_nr(pfn
)));
1234 * These are _only_ used during initialisation, therefore they
1235 * can use __initdata ... They could have names to indicate
1239 #define pfn_to_nid(pfn) \
1241 unsigned long __pfn_to_nid_pfn = (pfn); \
1242 page_to_nid(pfn_to_page(__pfn_to_nid_pfn)); \
1245 #define pfn_to_nid(pfn) (0)
1248 #define early_pfn_valid(pfn) pfn_valid(pfn)
1249 void sparse_init(void);
1251 #define sparse_init() do {} while (0)
1252 #define sparse_index_init(_sec, _nid) do {} while (0)
1253 #endif /* CONFIG_SPARSEMEM */
1256 * During memory init memblocks map pfns to nids. The search is expensive and
1257 * this caches recent lookups. The implementation of __early_pfn_to_nid
1258 * may treat start/end as pfns or sections.
1260 struct mminit_pfnnid_cache
{
1261 unsigned long last_start
;
1262 unsigned long last_end
;
1266 #ifndef early_pfn_valid
1267 #define early_pfn_valid(pfn) (1)
1270 void memory_present(int nid
, unsigned long start
, unsigned long end
);
1271 unsigned long __init
node_memmap_size_bytes(int, unsigned long, unsigned long);
1274 * If it is possible to have holes within a MAX_ORDER_NR_PAGES, then we
1275 * need to check pfn validility within that MAX_ORDER_NR_PAGES block.
1276 * pfn_valid_within() should be used in this case; we optimise this away
1277 * when we have no holes within a MAX_ORDER_NR_PAGES block.
1279 #ifdef CONFIG_HOLES_IN_ZONE
1280 #define pfn_valid_within(pfn) pfn_valid(pfn)
1282 #define pfn_valid_within(pfn) (1)
1285 #ifdef CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
1287 * pfn_valid() is meant to be able to tell if a given PFN has valid memmap
1288 * associated with it or not. This means that a struct page exists for this
1289 * pfn. The caller cannot assume the page is fully initialized in general.
1290 * Hotplugable pages might not have been onlined yet. pfn_to_online_page()
1291 * will ensure the struct page is fully online and initialized. Special pages
1292 * (e.g. ZONE_DEVICE) are never onlined and should be treated accordingly.
1294 * In FLATMEM, it is expected that holes always have valid memmap as long as
1295 * there is valid PFNs either side of the hole. In SPARSEMEM, it is assumed
1296 * that a valid section has a memmap for the entire section.
1298 * However, an ARM, and maybe other embedded architectures in the future
1299 * free memmap backing holes to save memory on the assumption the memmap is
1300 * never used. The page_zone linkages are then broken even though pfn_valid()
1301 * returns true. A walker of the full memmap must then do this additional
1302 * check to ensure the memmap they are looking at is sane by making sure
1303 * the zone and PFN linkages are still valid. This is expensive, but walkers
1304 * of the full memmap are extremely rare.
1306 bool memmap_valid_within(unsigned long pfn
,
1307 struct page
*page
, struct zone
*zone
);
1309 static inline bool memmap_valid_within(unsigned long pfn
,
1310 struct page
*page
, struct zone
*zone
)
1314 #endif /* CONFIG_ARCH_HAS_HOLES_MEMORYMODEL */
1316 #endif /* !__GENERATING_BOUNDS.H */
1317 #endif /* !__ASSEMBLY__ */
1318 #endif /* _LINUX_MMZONE_H */