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 */
67 # define is_migrate_cma(migratetype) unlikely((migratetype) == MIGRATE_CMA)
69 # define is_migrate_cma(migratetype) false
72 #define for_each_migratetype_order(order, type) \
73 for (order = 0; order < MAX_ORDER; order++) \
74 for (type = 0; type < MIGRATE_TYPES; type++)
76 extern int page_group_by_mobility_disabled
;
78 #define NR_MIGRATETYPE_BITS (PB_migrate_end - PB_migrate + 1)
79 #define MIGRATETYPE_MASK ((1UL << NR_MIGRATETYPE_BITS) - 1)
81 #define get_pageblock_migratetype(page) \
82 get_pfnblock_flags_mask(page, page_to_pfn(page), \
83 PB_migrate_end, MIGRATETYPE_MASK)
85 static inline int get_pfnblock_migratetype(struct page
*page
, unsigned long pfn
)
87 BUILD_BUG_ON(PB_migrate_end
- PB_migrate
!= 2);
88 return get_pfnblock_flags_mask(page
, pfn
, PB_migrate_end
,
93 struct list_head free_list
[MIGRATE_TYPES
];
94 unsigned long nr_free
;
100 * zone->lock and zone->lru_lock are two of the hottest locks in the kernel.
101 * So add a wild amount of padding here to ensure that they fall into separate
102 * cachelines. There are very few zone structures in the machine, so space
103 * consumption is not a concern here.
105 #if defined(CONFIG_SMP)
106 struct zone_padding
{
108 } ____cacheline_internodealigned_in_smp
;
109 #define ZONE_PADDING(name) struct zone_padding name;
111 #define ZONE_PADDING(name)
114 enum zone_stat_item
{
115 /* First 128 byte cacheline (assuming 64 bit words) */
119 NR_INACTIVE_ANON
= NR_LRU_BASE
, /* must match order of LRU_[IN]ACTIVE */
120 NR_ACTIVE_ANON
, /* " " " " " */
121 NR_INACTIVE_FILE
, /* " " " " " */
122 NR_ACTIVE_FILE
, /* " " " " " */
123 NR_UNEVICTABLE
, /* " " " " " */
124 NR_MLOCK
, /* mlock()ed pages found and moved off LRU */
125 NR_ANON_PAGES
, /* Mapped anonymous pages */
126 NR_FILE_MAPPED
, /* pagecache pages mapped into pagetables.
127 only modified from process context */
132 NR_SLAB_UNRECLAIMABLE
,
133 NR_PAGETABLE
, /* used for pagetables */
135 /* Second 128 byte cacheline */
136 NR_UNSTABLE_NFS
, /* NFS unstable pages */
139 NR_VMSCAN_IMMEDIATE
, /* Prioritise for reclaim when writeback ends */
140 NR_WRITEBACK_TEMP
, /* Writeback using temporary buffers */
141 NR_ISOLATED_ANON
, /* Temporary isolated pages from anon lru */
142 NR_ISOLATED_FILE
, /* Temporary isolated pages from file lru */
143 NR_SHMEM
, /* shmem pages (included tmpfs/GEM pages) */
144 NR_DIRTIED
, /* page dirtyings since bootup */
145 NR_WRITTEN
, /* page writings since bootup */
146 NR_PAGES_SCANNED
, /* pages scanned since last reclaim */
148 NUMA_HIT
, /* allocated in intended node */
149 NUMA_MISS
, /* allocated in non intended node */
150 NUMA_FOREIGN
, /* was intended here, hit elsewhere */
151 NUMA_INTERLEAVE_HIT
, /* interleaver preferred this zone */
152 NUMA_LOCAL
, /* allocation from local node */
153 NUMA_OTHER
, /* allocation from other node */
157 WORKINGSET_NODERECLAIM
,
158 NR_ANON_TRANSPARENT_HUGEPAGES
,
160 NR_VM_ZONE_STAT_ITEMS
};
163 * We do arithmetic on the LRU lists in various places in the code,
164 * so it is important to keep the active lists LRU_ACTIVE higher in
165 * the array than the corresponding inactive lists, and to keep
166 * the *_FILE lists LRU_FILE higher than the corresponding _ANON lists.
168 * This has to be kept in sync with the statistics in zone_stat_item
169 * above and the descriptions in vmstat_text in mm/vmstat.c
176 LRU_INACTIVE_ANON
= LRU_BASE
,
177 LRU_ACTIVE_ANON
= LRU_BASE
+ LRU_ACTIVE
,
178 LRU_INACTIVE_FILE
= LRU_BASE
+ LRU_FILE
,
179 LRU_ACTIVE_FILE
= LRU_BASE
+ LRU_FILE
+ LRU_ACTIVE
,
184 #define for_each_lru(lru) for (lru = 0; lru < NR_LRU_LISTS; lru++)
186 #define for_each_evictable_lru(lru) for (lru = 0; lru <= LRU_ACTIVE_FILE; lru++)
188 static inline int is_file_lru(enum lru_list lru
)
190 return (lru
== LRU_INACTIVE_FILE
|| lru
== LRU_ACTIVE_FILE
);
193 static inline int is_active_lru(enum lru_list lru
)
195 return (lru
== LRU_ACTIVE_ANON
|| lru
== LRU_ACTIVE_FILE
);
198 static inline int is_unevictable_lru(enum lru_list lru
)
200 return (lru
== LRU_UNEVICTABLE
);
203 struct zone_reclaim_stat
{
205 * The pageout code in vmscan.c keeps track of how many of the
206 * mem/swap backed and file backed pages are referenced.
207 * The higher the rotated/scanned ratio, the more valuable
210 * The anon LRU stats live in [0], file LRU stats in [1]
212 unsigned long recent_rotated
[2];
213 unsigned long recent_scanned
[2];
217 struct list_head lists
[NR_LRU_LISTS
];
218 struct zone_reclaim_stat reclaim_stat
;
224 /* Mask used at gathering information at once (see memcontrol.c) */
225 #define LRU_ALL_FILE (BIT(LRU_INACTIVE_FILE) | BIT(LRU_ACTIVE_FILE))
226 #define LRU_ALL_ANON (BIT(LRU_INACTIVE_ANON) | BIT(LRU_ACTIVE_ANON))
227 #define LRU_ALL ((1 << NR_LRU_LISTS) - 1)
229 /* Isolate clean file */
230 #define ISOLATE_CLEAN ((__force isolate_mode_t)0x1)
231 /* Isolate unmapped file */
232 #define ISOLATE_UNMAPPED ((__force isolate_mode_t)0x2)
233 /* Isolate for asynchronous migration */
234 #define ISOLATE_ASYNC_MIGRATE ((__force isolate_mode_t)0x4)
235 /* Isolate unevictable pages */
236 #define ISOLATE_UNEVICTABLE ((__force isolate_mode_t)0x8)
238 /* LRU Isolation modes. */
239 typedef unsigned __bitwise__ isolate_mode_t
;
241 enum zone_watermarks
{
248 #define min_wmark_pages(z) (z->watermark[WMARK_MIN])
249 #define low_wmark_pages(z) (z->watermark[WMARK_LOW])
250 #define high_wmark_pages(z) (z->watermark[WMARK_HIGH])
252 struct per_cpu_pages
{
253 int count
; /* number of pages in the list */
254 int high
; /* high watermark, emptying needed */
255 int batch
; /* chunk size for buddy add/remove */
257 /* Lists of pages, one per migrate type stored on the pcp-lists */
258 struct list_head lists
[MIGRATE_PCPTYPES
];
261 struct per_cpu_pageset
{
262 struct per_cpu_pages pcp
;
268 s8 vm_stat_diff
[NR_VM_ZONE_STAT_ITEMS
];
272 #endif /* !__GENERATING_BOUNDS.H */
275 #ifdef CONFIG_ZONE_DMA
277 * ZONE_DMA is used when there are devices that are not able
278 * to do DMA to all of addressable memory (ZONE_NORMAL). Then we
279 * carve out the portion of memory that is needed for these devices.
280 * The range is arch specific.
285 * ---------------------------
286 * parisc, ia64, sparc <4G
289 * alpha Unlimited or 0-16MB.
291 * i386, x86_64 and multiple other arches
296 #ifdef CONFIG_ZONE_DMA32
298 * x86_64 needs two ZONE_DMAs because it supports devices that are
299 * only able to do DMA to the lower 16M but also 32 bit devices that
300 * can only do DMA areas below 4G.
305 * Normal addressable memory is in ZONE_NORMAL. DMA operations can be
306 * performed on pages in ZONE_NORMAL if the DMA devices support
307 * transfers to all addressable memory.
310 #ifdef CONFIG_HIGHMEM
312 * A memory area that is only addressable by the kernel through
313 * mapping portions into its own address space. This is for example
314 * used by i386 to allow the kernel to address the memory beyond
315 * 900MB. The kernel will set up special mappings (page
316 * table entries on i386) for each page that the kernel needs to
322 #ifdef CONFIG_ZONE_DEVICE
329 #ifndef __GENERATING_BOUNDS_H
332 /* Read-mostly fields */
334 /* zone watermarks, access with *_wmark_pages(zone) macros */
335 unsigned long watermark
[NR_WMARK
];
337 unsigned long nr_reserved_highatomic
;
340 * We don't know if the memory that we're going to allocate will be
341 * freeable or/and it will be released eventually, so to avoid totally
342 * wasting several GB of ram we must reserve some of the lower zone
343 * memory (otherwise we risk to run OOM on the lower zones despite
344 * there being tons of freeable ram on the higher zones). This array is
345 * recalculated at runtime if the sysctl_lowmem_reserve_ratio sysctl
348 long lowmem_reserve
[MAX_NR_ZONES
];
355 * The target ratio of ACTIVE_ANON to INACTIVE_ANON pages on
356 * this zone's LRU. Maintained by the pageout code.
358 unsigned int inactive_ratio
;
360 struct pglist_data
*zone_pgdat
;
361 struct per_cpu_pageset __percpu
*pageset
;
364 * This is a per-zone reserve of pages that should not be
365 * considered dirtyable memory.
367 unsigned long dirty_balance_reserve
;
369 #ifndef CONFIG_SPARSEMEM
371 * Flags for a pageblock_nr_pages block. See pageblock-flags.h.
372 * In SPARSEMEM, this map is stored in struct mem_section
374 unsigned long *pageblock_flags
;
375 #endif /* CONFIG_SPARSEMEM */
379 * zone reclaim becomes active if more unmapped pages exist.
381 unsigned long min_unmapped_pages
;
382 unsigned long min_slab_pages
;
383 #endif /* CONFIG_NUMA */
385 /* zone_start_pfn == zone_start_paddr >> PAGE_SHIFT */
386 unsigned long zone_start_pfn
;
389 * spanned_pages is the total pages spanned by the zone, including
390 * holes, which is calculated as:
391 * spanned_pages = zone_end_pfn - zone_start_pfn;
393 * present_pages is physical pages existing within the zone, which
395 * present_pages = spanned_pages - absent_pages(pages in holes);
397 * managed_pages is present pages managed by the buddy system, which
398 * is calculated as (reserved_pages includes pages allocated by the
399 * bootmem allocator):
400 * managed_pages = present_pages - reserved_pages;
402 * So present_pages may be used by memory hotplug or memory power
403 * management logic to figure out unmanaged pages by checking
404 * (present_pages - managed_pages). And managed_pages should be used
405 * by page allocator and vm scanner to calculate all kinds of watermarks
410 * zone_start_pfn and spanned_pages are protected by span_seqlock.
411 * It is a seqlock because it has to be read outside of zone->lock,
412 * and it is done in the main allocator path. But, it is written
413 * quite infrequently.
415 * The span_seq lock is declared along with zone->lock because it is
416 * frequently read in proximity to zone->lock. It's good to
417 * give them a chance of being in the same cacheline.
419 * Write access to present_pages at runtime should be protected by
420 * mem_hotplug_begin/end(). Any reader who can't tolerant drift of
421 * present_pages should get_online_mems() to get a stable value.
423 * Read access to managed_pages should be safe because it's unsigned
424 * long. Write access to zone->managed_pages and totalram_pages are
425 * protected by managed_page_count_lock at runtime. Idealy only
426 * adjust_managed_page_count() should be used instead of directly
427 * touching zone->managed_pages and totalram_pages.
429 unsigned long managed_pages
;
430 unsigned long spanned_pages
;
431 unsigned long present_pages
;
435 #ifdef CONFIG_MEMORY_ISOLATION
437 * Number of isolated pageblock. It is used to solve incorrect
438 * freepage counting problem due to racy retrieving migratetype
439 * of pageblock. Protected by zone->lock.
441 unsigned long nr_isolate_pageblock
;
444 #ifdef CONFIG_MEMORY_HOTPLUG
445 /* see spanned/present_pages for more description */
446 seqlock_t span_seqlock
;
450 * wait_table -- the array holding the hash table
451 * wait_table_hash_nr_entries -- the size of the hash table array
452 * wait_table_bits -- wait_table_size == (1 << wait_table_bits)
454 * The purpose of all these is to keep track of the people
455 * waiting for a page to become available and make them
456 * runnable again when possible. The trouble is that this
457 * consumes a lot of space, especially when so few things
458 * wait on pages at a given time. So instead of using
459 * per-page waitqueues, we use a waitqueue hash table.
461 * The bucket discipline is to sleep on the same queue when
462 * colliding and wake all in that wait queue when removing.
463 * When something wakes, it must check to be sure its page is
464 * truly available, a la thundering herd. The cost of a
465 * collision is great, but given the expected load of the
466 * table, they should be so rare as to be outweighed by the
467 * benefits from the saved space.
469 * __wait_on_page_locked() and unlock_page() in mm/filemap.c, are the
470 * primary users of these fields, and in mm/page_alloc.c
471 * free_area_init_core() performs the initialization of them.
473 wait_queue_head_t
*wait_table
;
474 unsigned long wait_table_hash_nr_entries
;
475 unsigned long wait_table_bits
;
478 /* free areas of different sizes */
479 struct free_area free_area
[MAX_ORDER
];
481 /* zone flags, see below */
484 /* Write-intensive fields used from the page allocator */
489 /* Write-intensive fields used by page reclaim */
491 /* Fields commonly accessed by the page reclaim scanner */
493 struct lruvec lruvec
;
495 /* Evictions & activations on the inactive file list */
496 atomic_long_t inactive_age
;
499 * When free pages are below this point, additional steps are taken
500 * when reading the number of free pages to avoid per-cpu counter
501 * drift allowing watermarks to be breached
503 unsigned long percpu_drift_mark
;
505 #if defined CONFIG_COMPACTION || defined CONFIG_CMA
506 /* pfn where compaction free scanner should start */
507 unsigned long compact_cached_free_pfn
;
508 /* pfn where async and sync compaction migration scanner should start */
509 unsigned long compact_cached_migrate_pfn
[2];
512 #ifdef CONFIG_COMPACTION
514 * On compaction failure, 1<<compact_defer_shift compactions
515 * are skipped before trying again. The number attempted since
516 * last failure is tracked with compact_considered.
518 unsigned int compact_considered
;
519 unsigned int compact_defer_shift
;
520 int compact_order_failed
;
523 #if defined CONFIG_COMPACTION || defined CONFIG_CMA
524 /* Set to true when the PG_migrate_skip bits should be cleared */
525 bool compact_blockskip_flush
;
529 /* Zone statistics */
530 atomic_long_t vm_stat
[NR_VM_ZONE_STAT_ITEMS
];
531 } ____cacheline_internodealigned_in_smp
;
534 ZONE_RECLAIM_LOCKED
, /* prevents concurrent reclaim */
535 ZONE_OOM_LOCKED
, /* zone is in OOM killer zonelist */
536 ZONE_CONGESTED
, /* zone has many dirty pages backed by
539 ZONE_DIRTY
, /* reclaim scanning has recently found
540 * many dirty file pages at the tail
543 ZONE_WRITEBACK
, /* reclaim scanning has recently found
544 * many pages under writeback
546 ZONE_FAIR_DEPLETED
, /* fair zone policy batch depleted */
549 static inline unsigned long zone_end_pfn(const struct zone
*zone
)
551 return zone
->zone_start_pfn
+ zone
->spanned_pages
;
554 static inline bool zone_spans_pfn(const struct zone
*zone
, unsigned long pfn
)
556 return zone
->zone_start_pfn
<= pfn
&& pfn
< zone_end_pfn(zone
);
559 static inline bool zone_is_initialized(struct zone
*zone
)
561 return !!zone
->wait_table
;
564 static inline bool zone_is_empty(struct zone
*zone
)
566 return zone
->spanned_pages
== 0;
570 * The "priority" of VM scanning is how much of the queues we will scan in one
571 * go. A value of 12 for DEF_PRIORITY implies that we will scan 1/4096th of the
572 * queues ("queue_length >> 12") during an aging round.
574 #define DEF_PRIORITY 12
576 /* Maximum number of zones on a zonelist */
577 #define MAX_ZONES_PER_ZONELIST (MAX_NUMNODES * MAX_NR_ZONES)
582 * The NUMA zonelists are doubled because we need zonelists that restrict the
583 * allocations to a single node for __GFP_THISNODE.
585 * [0] : Zonelist with fallback
586 * [1] : No fallback (__GFP_THISNODE)
588 #define MAX_ZONELISTS 2
590 #define MAX_ZONELISTS 1
594 * This struct contains information about a zone in a zonelist. It is stored
595 * here to avoid dereferences into large structures and lookups of tables
598 struct zone
*zone
; /* Pointer to actual zone */
599 int zone_idx
; /* zone_idx(zoneref->zone) */
603 * One allocation request operates on a zonelist. A zonelist
604 * is a list of zones, the first one is the 'goal' of the
605 * allocation, the other zones are fallback zones, in decreasing
608 * To speed the reading of the zonelist, the zonerefs contain the zone index
609 * of the entry being read. Helper functions to access information given
610 * a struct zoneref are
612 * zonelist_zone() - Return the struct zone * for an entry in _zonerefs
613 * zonelist_zone_idx() - Return the index of the zone for an entry
614 * zonelist_node_idx() - Return the index of the node for an entry
617 struct zoneref _zonerefs
[MAX_ZONES_PER_ZONELIST
+ 1];
620 #ifndef CONFIG_DISCONTIGMEM
621 /* The array of struct pages - for discontigmem use pgdat->lmem_map */
622 extern struct page
*mem_map
;
626 * The pg_data_t structure is used in machines with CONFIG_DISCONTIGMEM
627 * (mostly NUMA machines?) to denote a higher-level memory zone than the
630 * On NUMA machines, each NUMA node would have a pg_data_t to describe
631 * it's memory layout.
633 * Memory statistics and page replacement data structures are maintained on a
637 typedef struct pglist_data
{
638 struct zone node_zones
[MAX_NR_ZONES
];
639 struct zonelist node_zonelists
[MAX_ZONELISTS
];
641 #ifdef CONFIG_FLAT_NODE_MEM_MAP /* means !SPARSEMEM */
642 struct page
*node_mem_map
;
643 #ifdef CONFIG_PAGE_EXTENSION
644 struct page_ext
*node_page_ext
;
647 #ifndef CONFIG_NO_BOOTMEM
648 struct bootmem_data
*bdata
;
650 #ifdef CONFIG_MEMORY_HOTPLUG
652 * Must be held any time you expect node_start_pfn, node_present_pages
653 * or node_spanned_pages stay constant. Holding this will also
654 * guarantee that any pfn_valid() stays that way.
656 * pgdat_resize_lock() and pgdat_resize_unlock() are provided to
657 * manipulate node_size_lock without checking for CONFIG_MEMORY_HOTPLUG.
659 * Nests above zone->lock and zone->span_seqlock
661 spinlock_t node_size_lock
;
663 unsigned long node_start_pfn
;
664 unsigned long node_present_pages
; /* total number of physical pages */
665 unsigned long node_spanned_pages
; /* total size of physical page
666 range, including holes */
668 wait_queue_head_t kswapd_wait
;
669 wait_queue_head_t pfmemalloc_wait
;
670 struct task_struct
*kswapd
; /* Protected by
671 mem_hotplug_begin/end() */
672 int kswapd_max_order
;
673 enum zone_type classzone_idx
;
674 #ifdef CONFIG_NUMA_BALANCING
675 /* Lock serializing the migrate rate limiting window */
676 spinlock_t numabalancing_migrate_lock
;
678 /* Rate limiting time interval */
679 unsigned long numabalancing_migrate_next_window
;
681 /* Number of pages migrated during the rate limiting time interval */
682 unsigned long numabalancing_migrate_nr_pages
;
685 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
687 * If memory initialisation on large machines is deferred then this
688 * is the first PFN that needs to be initialised.
690 unsigned long first_deferred_pfn
;
691 #endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */
694 #define node_present_pages(nid) (NODE_DATA(nid)->node_present_pages)
695 #define node_spanned_pages(nid) (NODE_DATA(nid)->node_spanned_pages)
696 #ifdef CONFIG_FLAT_NODE_MEM_MAP
697 #define pgdat_page_nr(pgdat, pagenr) ((pgdat)->node_mem_map + (pagenr))
699 #define pgdat_page_nr(pgdat, pagenr) pfn_to_page((pgdat)->node_start_pfn + (pagenr))
701 #define nid_page_nr(nid, pagenr) pgdat_page_nr(NODE_DATA(nid),(pagenr))
703 #define node_start_pfn(nid) (NODE_DATA(nid)->node_start_pfn)
704 #define node_end_pfn(nid) pgdat_end_pfn(NODE_DATA(nid))
706 static inline unsigned long pgdat_end_pfn(pg_data_t
*pgdat
)
708 return pgdat
->node_start_pfn
+ pgdat
->node_spanned_pages
;
711 static inline bool pgdat_is_empty(pg_data_t
*pgdat
)
713 return !pgdat
->node_start_pfn
&& !pgdat
->node_spanned_pages
;
716 static inline int zone_id(const struct zone
*zone
)
718 struct pglist_data
*pgdat
= zone
->zone_pgdat
;
720 return zone
- pgdat
->node_zones
;
723 #ifdef CONFIG_ZONE_DEVICE
724 static inline bool is_dev_zone(const struct zone
*zone
)
726 return zone_id(zone
) == ZONE_DEVICE
;
729 static inline bool is_dev_zone(const struct zone
*zone
)
735 #include <linux/memory_hotplug.h>
737 extern struct mutex zonelists_mutex
;
738 void build_all_zonelists(pg_data_t
*pgdat
, struct zone
*zone
);
739 void wakeup_kswapd(struct zone
*zone
, int order
, enum zone_type classzone_idx
);
740 bool zone_watermark_ok(struct zone
*z
, unsigned int order
,
741 unsigned long mark
, int classzone_idx
, int alloc_flags
);
742 bool zone_watermark_ok_safe(struct zone
*z
, unsigned int order
,
743 unsigned long mark
, int classzone_idx
);
744 enum memmap_context
{
748 extern int init_currently_empty_zone(struct zone
*zone
, unsigned long start_pfn
,
751 extern void lruvec_init(struct lruvec
*lruvec
);
753 static inline struct zone
*lruvec_zone(struct lruvec
*lruvec
)
758 return container_of(lruvec
, struct zone
, lruvec
);
762 #ifdef CONFIG_HAVE_MEMORY_PRESENT
763 void memory_present(int nid
, unsigned long start
, unsigned long end
);
765 static inline void memory_present(int nid
, unsigned long start
, unsigned long end
) {}
768 #ifdef CONFIG_HAVE_MEMORYLESS_NODES
769 int local_memory_node(int node_id
);
771 static inline int local_memory_node(int node_id
) { return node_id
; };
774 #ifdef CONFIG_NEED_NODE_MEMMAP_SIZE
775 unsigned long __init
node_memmap_size_bytes(int, unsigned long, unsigned long);
779 * zone_idx() returns 0 for the ZONE_DMA zone, 1 for the ZONE_NORMAL zone, etc.
781 #define zone_idx(zone) ((zone) - (zone)->zone_pgdat->node_zones)
783 static inline int populated_zone(struct zone
*zone
)
785 return (!!zone
->present_pages
);
788 extern int movable_zone
;
790 #ifdef CONFIG_HIGHMEM
791 static inline int zone_movable_is_highmem(void)
793 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
794 return movable_zone
== ZONE_HIGHMEM
;
796 return (ZONE_MOVABLE
- 1) == ZONE_HIGHMEM
;
801 static inline int is_highmem_idx(enum zone_type idx
)
803 #ifdef CONFIG_HIGHMEM
804 return (idx
== ZONE_HIGHMEM
||
805 (idx
== ZONE_MOVABLE
&& zone_movable_is_highmem()));
812 * is_highmem - helper function to quickly check if a struct zone is a
813 * highmem zone or not. This is an attempt to keep references
814 * to ZONE_{DMA/NORMAL/HIGHMEM/etc} in general code to a minimum.
815 * @zone - pointer to struct zone variable
817 static inline int is_highmem(struct zone
*zone
)
819 #ifdef CONFIG_HIGHMEM
820 int zone_off
= (char *)zone
- (char *)zone
->zone_pgdat
->node_zones
;
821 return zone_off
== ZONE_HIGHMEM
* sizeof(*zone
) ||
822 (zone_off
== ZONE_MOVABLE
* sizeof(*zone
) &&
823 zone_movable_is_highmem());
829 /* These two functions are used to setup the per zone pages min values */
831 int min_free_kbytes_sysctl_handler(struct ctl_table
*, int,
832 void __user
*, size_t *, loff_t
*);
833 extern int sysctl_lowmem_reserve_ratio
[MAX_NR_ZONES
-1];
834 int lowmem_reserve_ratio_sysctl_handler(struct ctl_table
*, int,
835 void __user
*, size_t *, loff_t
*);
836 int percpu_pagelist_fraction_sysctl_handler(struct ctl_table
*, int,
837 void __user
*, size_t *, loff_t
*);
838 int sysctl_min_unmapped_ratio_sysctl_handler(struct ctl_table
*, int,
839 void __user
*, size_t *, loff_t
*);
840 int sysctl_min_slab_ratio_sysctl_handler(struct ctl_table
*, int,
841 void __user
*, size_t *, loff_t
*);
843 extern int numa_zonelist_order_handler(struct ctl_table
*, int,
844 void __user
*, size_t *, loff_t
*);
845 extern char numa_zonelist_order
[];
846 #define NUMA_ZONELIST_ORDER_LEN 16 /* string buffer size */
848 #ifndef CONFIG_NEED_MULTIPLE_NODES
850 extern struct pglist_data contig_page_data
;
851 #define NODE_DATA(nid) (&contig_page_data)
852 #define NODE_MEM_MAP(nid) mem_map
854 #else /* CONFIG_NEED_MULTIPLE_NODES */
856 #include <asm/mmzone.h>
858 #endif /* !CONFIG_NEED_MULTIPLE_NODES */
860 extern struct pglist_data
*first_online_pgdat(void);
861 extern struct pglist_data
*next_online_pgdat(struct pglist_data
*pgdat
);
862 extern struct zone
*next_zone(struct zone
*zone
);
865 * for_each_online_pgdat - helper macro to iterate over all online nodes
866 * @pgdat - pointer to a pg_data_t variable
868 #define for_each_online_pgdat(pgdat) \
869 for (pgdat = first_online_pgdat(); \
871 pgdat = next_online_pgdat(pgdat))
873 * for_each_zone - helper macro to iterate over all memory zones
874 * @zone - pointer to struct zone variable
876 * The user only needs to declare the zone variable, for_each_zone
879 #define for_each_zone(zone) \
880 for (zone = (first_online_pgdat())->node_zones; \
882 zone = next_zone(zone))
884 #define for_each_populated_zone(zone) \
885 for (zone = (first_online_pgdat())->node_zones; \
887 zone = next_zone(zone)) \
888 if (!populated_zone(zone)) \
892 static inline struct zone
*zonelist_zone(struct zoneref
*zoneref
)
894 return zoneref
->zone
;
897 static inline int zonelist_zone_idx(struct zoneref
*zoneref
)
899 return zoneref
->zone_idx
;
902 static inline int zonelist_node_idx(struct zoneref
*zoneref
)
905 /* zone_to_nid not available in this context */
906 return zoneref
->zone
->node
;
909 #endif /* CONFIG_NUMA */
913 * 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
914 * @z - The cursor used as a starting point for the search
915 * @highest_zoneidx - The zone index of the highest zone to return
916 * @nodes - An optional nodemask to filter the zonelist with
918 * This function returns the next zone at or below a given zone index that is
919 * within the allowed nodemask using a cursor as the starting point for the
920 * search. The zoneref returned is a cursor that represents the current zone
921 * being examined. It should be advanced by one before calling
922 * next_zones_zonelist again.
924 struct zoneref
*next_zones_zonelist(struct zoneref
*z
,
925 enum zone_type highest_zoneidx
,
929 * first_zones_zonelist - Returns the first zone at or below highest_zoneidx within the allowed nodemask in a zonelist
930 * @zonelist - The zonelist to search for a suitable zone
931 * @highest_zoneidx - The zone index of the highest zone to return
932 * @nodes - An optional nodemask to filter the zonelist with
933 * @zone - The first suitable zone found is returned via this parameter
935 * This function returns the first zone at or below a given zone index that is
936 * within the allowed nodemask. The zoneref returned is a cursor that can be
937 * used to iterate the zonelist with next_zones_zonelist by advancing it by
938 * one before calling.
940 static inline struct zoneref
*first_zones_zonelist(struct zonelist
*zonelist
,
941 enum zone_type highest_zoneidx
,
945 struct zoneref
*z
= next_zones_zonelist(zonelist
->_zonerefs
,
946 highest_zoneidx
, nodes
);
947 *zone
= zonelist_zone(z
);
952 * 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
953 * @zone - The current zone in the iterator
954 * @z - The current pointer within zonelist->zones being iterated
955 * @zlist - The zonelist being iterated
956 * @highidx - The zone index of the highest zone to return
957 * @nodemask - Nodemask allowed by the allocator
959 * This iterator iterates though all zones at or below a given zone index and
960 * within a given nodemask
962 #define for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, nodemask) \
963 for (z = first_zones_zonelist(zlist, highidx, nodemask, &zone); \
965 z = next_zones_zonelist(++z, highidx, nodemask), \
966 zone = zonelist_zone(z)) \
969 * for_each_zone_zonelist - helper macro to iterate over valid zones in a zonelist at or below a given zone index
970 * @zone - The current zone in the iterator
971 * @z - The current pointer within zonelist->zones being iterated
972 * @zlist - The zonelist being iterated
973 * @highidx - The zone index of the highest zone to return
975 * This iterator iterates though all zones at or below a given zone index.
977 #define for_each_zone_zonelist(zone, z, zlist, highidx) \
978 for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, NULL)
980 #ifdef CONFIG_SPARSEMEM
981 #include <asm/sparsemem.h>
984 #if !defined(CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID) && \
985 !defined(CONFIG_HAVE_MEMBLOCK_NODE_MAP)
986 static inline unsigned long early_pfn_to_nid(unsigned long pfn
)
992 #ifdef CONFIG_FLATMEM
993 #define pfn_to_nid(pfn) (0)
996 #ifdef CONFIG_SPARSEMEM
999 * SECTION_SHIFT #bits space required to store a section #
1001 * PA_SECTION_SHIFT physical address to/from section number
1002 * PFN_SECTION_SHIFT pfn to/from section number
1004 #define PA_SECTION_SHIFT (SECTION_SIZE_BITS)
1005 #define PFN_SECTION_SHIFT (SECTION_SIZE_BITS - PAGE_SHIFT)
1007 #define NR_MEM_SECTIONS (1UL << SECTIONS_SHIFT)
1009 #define PAGES_PER_SECTION (1UL << PFN_SECTION_SHIFT)
1010 #define PAGE_SECTION_MASK (~(PAGES_PER_SECTION-1))
1012 #define SECTION_BLOCKFLAGS_BITS \
1013 ((1UL << (PFN_SECTION_SHIFT - pageblock_order)) * NR_PAGEBLOCK_BITS)
1015 #if (MAX_ORDER - 1 + PAGE_SHIFT) > SECTION_SIZE_BITS
1016 #error Allocator MAX_ORDER exceeds SECTION_SIZE
1019 #define pfn_to_section_nr(pfn) ((pfn) >> PFN_SECTION_SHIFT)
1020 #define section_nr_to_pfn(sec) ((sec) << PFN_SECTION_SHIFT)
1022 #define SECTION_ALIGN_UP(pfn) (((pfn) + PAGES_PER_SECTION - 1) & PAGE_SECTION_MASK)
1023 #define SECTION_ALIGN_DOWN(pfn) ((pfn) & PAGE_SECTION_MASK)
1027 struct mem_section
{
1029 * This is, logically, a pointer to an array of struct
1030 * pages. However, it is stored with some other magic.
1031 * (see sparse.c::sparse_init_one_section())
1033 * Additionally during early boot we encode node id of
1034 * the location of the section here to guide allocation.
1035 * (see sparse.c::memory_present())
1037 * Making it a UL at least makes someone do a cast
1038 * before using it wrong.
1040 unsigned long section_mem_map
;
1042 /* See declaration of similar field in struct zone */
1043 unsigned long *pageblock_flags
;
1044 #ifdef CONFIG_PAGE_EXTENSION
1046 * If !SPARSEMEM, pgdat doesn't have page_ext pointer. We use
1047 * section. (see page_ext.h about this.)
1049 struct page_ext
*page_ext
;
1053 * WARNING: mem_section must be a power-of-2 in size for the
1054 * calculation and use of SECTION_ROOT_MASK to make sense.
1058 #ifdef CONFIG_SPARSEMEM_EXTREME
1059 #define SECTIONS_PER_ROOT (PAGE_SIZE / sizeof (struct mem_section))
1061 #define SECTIONS_PER_ROOT 1
1064 #define SECTION_NR_TO_ROOT(sec) ((sec) / SECTIONS_PER_ROOT)
1065 #define NR_SECTION_ROOTS DIV_ROUND_UP(NR_MEM_SECTIONS, SECTIONS_PER_ROOT)
1066 #define SECTION_ROOT_MASK (SECTIONS_PER_ROOT - 1)
1068 #ifdef CONFIG_SPARSEMEM_EXTREME
1069 extern struct mem_section
*mem_section
[NR_SECTION_ROOTS
];
1071 extern struct mem_section mem_section
[NR_SECTION_ROOTS
][SECTIONS_PER_ROOT
];
1074 static inline struct mem_section
*__nr_to_section(unsigned long nr
)
1076 if (!mem_section
[SECTION_NR_TO_ROOT(nr
)])
1078 return &mem_section
[SECTION_NR_TO_ROOT(nr
)][nr
& SECTION_ROOT_MASK
];
1080 extern int __section_nr(struct mem_section
* ms
);
1081 extern unsigned long usemap_size(void);
1084 * We use the lower bits of the mem_map pointer to store
1085 * a little bit of information. There should be at least
1086 * 3 bits here due to 32-bit alignment.
1088 #define SECTION_MARKED_PRESENT (1UL<<0)
1089 #define SECTION_HAS_MEM_MAP (1UL<<1)
1090 #define SECTION_MAP_LAST_BIT (1UL<<2)
1091 #define SECTION_MAP_MASK (~(SECTION_MAP_LAST_BIT-1))
1092 #define SECTION_NID_SHIFT 2
1094 static inline struct page
*__section_mem_map_addr(struct mem_section
*section
)
1096 unsigned long map
= section
->section_mem_map
;
1097 map
&= SECTION_MAP_MASK
;
1098 return (struct page
*)map
;
1101 static inline int present_section(struct mem_section
*section
)
1103 return (section
&& (section
->section_mem_map
& SECTION_MARKED_PRESENT
));
1106 static inline int present_section_nr(unsigned long nr
)
1108 return present_section(__nr_to_section(nr
));
1111 static inline int valid_section(struct mem_section
*section
)
1113 return (section
&& (section
->section_mem_map
& SECTION_HAS_MEM_MAP
));
1116 static inline int valid_section_nr(unsigned long nr
)
1118 return valid_section(__nr_to_section(nr
));
1121 static inline struct mem_section
*__pfn_to_section(unsigned long pfn
)
1123 return __nr_to_section(pfn_to_section_nr(pfn
));
1126 #ifndef CONFIG_HAVE_ARCH_PFN_VALID
1127 static inline int pfn_valid(unsigned long pfn
)
1129 if (pfn_to_section_nr(pfn
) >= NR_MEM_SECTIONS
)
1131 return valid_section(__nr_to_section(pfn_to_section_nr(pfn
)));
1135 static inline int pfn_present(unsigned long pfn
)
1137 if (pfn_to_section_nr(pfn
) >= NR_MEM_SECTIONS
)
1139 return present_section(__nr_to_section(pfn_to_section_nr(pfn
)));
1143 * These are _only_ used during initialisation, therefore they
1144 * can use __initdata ... They could have names to indicate
1148 #define pfn_to_nid(pfn) \
1150 unsigned long __pfn_to_nid_pfn = (pfn); \
1151 page_to_nid(pfn_to_page(__pfn_to_nid_pfn)); \
1154 #define pfn_to_nid(pfn) (0)
1157 #define early_pfn_valid(pfn) pfn_valid(pfn)
1158 void sparse_init(void);
1160 #define sparse_init() do {} while (0)
1161 #define sparse_index_init(_sec, _nid) do {} while (0)
1162 #endif /* CONFIG_SPARSEMEM */
1165 * During memory init memblocks map pfns to nids. The search is expensive and
1166 * this caches recent lookups. The implementation of __early_pfn_to_nid
1167 * may treat start/end as pfns or sections.
1169 struct mminit_pfnnid_cache
{
1170 unsigned long last_start
;
1171 unsigned long last_end
;
1175 #ifndef early_pfn_valid
1176 #define early_pfn_valid(pfn) (1)
1179 void memory_present(int nid
, unsigned long start
, unsigned long end
);
1180 unsigned long __init
node_memmap_size_bytes(int, unsigned long, unsigned long);
1183 * If it is possible to have holes within a MAX_ORDER_NR_PAGES, then we
1184 * need to check pfn validility within that MAX_ORDER_NR_PAGES block.
1185 * pfn_valid_within() should be used in this case; we optimise this away
1186 * when we have no holes within a MAX_ORDER_NR_PAGES block.
1188 #ifdef CONFIG_HOLES_IN_ZONE
1189 #define pfn_valid_within(pfn) pfn_valid(pfn)
1191 #define pfn_valid_within(pfn) (1)
1194 #ifdef CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
1196 * pfn_valid() is meant to be able to tell if a given PFN has valid memmap
1197 * associated with it or not. In FLATMEM, it is expected that holes always
1198 * have valid memmap as long as there is valid PFNs either side of the hole.
1199 * In SPARSEMEM, it is assumed that a valid section has a memmap for the
1202 * However, an ARM, and maybe other embedded architectures in the future
1203 * free memmap backing holes to save memory on the assumption the memmap is
1204 * never used. The page_zone linkages are then broken even though pfn_valid()
1205 * returns true. A walker of the full memmap must then do this additional
1206 * check to ensure the memmap they are looking at is sane by making sure
1207 * the zone and PFN linkages are still valid. This is expensive, but walkers
1208 * of the full memmap are extremely rare.
1210 int memmap_valid_within(unsigned long pfn
,
1211 struct page
*page
, struct zone
*zone
);
1213 static inline int memmap_valid_within(unsigned long pfn
,
1214 struct page
*page
, struct zone
*zone
)
1218 #endif /* CONFIG_ARCH_HAS_HOLES_MEMORYMODEL */
1220 #endif /* !__GENERATING_BOUNDS.H */
1221 #endif /* !__ASSEMBLY__ */
1222 #endif /* _LINUX_MMZONE_H */