2 * linux/mm/page_alloc.c
4 * Manages the free list, the system allocates free pages here.
5 * Note that kmalloc() lives in slab.c
7 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
8 * Swap reorganised 29.12.95, Stephen Tweedie
9 * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999
10 * Reshaped it to be a zoned allocator, Ingo Molnar, Red Hat, 1999
11 * Discontiguous memory support, Kanoj Sarcar, SGI, Nov 1999
12 * Zone balancing, Kanoj Sarcar, SGI, Jan 2000
13 * Per cpu hot/cold page lists, bulk allocation, Martin J. Bligh, Sept 2002
14 * (lots of bits borrowed from Ingo Molnar & Andrew Morton)
17 #include <linux/stddef.h>
19 #include <linux/swap.h>
20 #include <linux/interrupt.h>
21 #include <linux/pagemap.h>
22 #include <linux/jiffies.h>
23 #include <linux/bootmem.h>
24 #include <linux/memblock.h>
25 #include <linux/compiler.h>
26 #include <linux/kernel.h>
27 #include <linux/kmemcheck.h>
28 #include <linux/kasan.h>
29 #include <linux/module.h>
30 #include <linux/suspend.h>
31 #include <linux/pagevec.h>
32 #include <linux/blkdev.h>
33 #include <linux/slab.h>
34 #include <linux/ratelimit.h>
35 #include <linux/oom.h>
36 #include <linux/notifier.h>
37 #include <linux/topology.h>
38 #include <linux/sysctl.h>
39 #include <linux/cpu.h>
40 #include <linux/cpuset.h>
41 #include <linux/memory_hotplug.h>
42 #include <linux/nodemask.h>
43 #include <linux/vmalloc.h>
44 #include <linux/vmstat.h>
45 #include <linux/mempolicy.h>
46 #include <linux/memremap.h>
47 #include <linux/stop_machine.h>
48 #include <linux/sort.h>
49 #include <linux/pfn.h>
50 #include <linux/backing-dev.h>
51 #include <linux/fault-inject.h>
52 #include <linux/page-isolation.h>
53 #include <linux/page_ext.h>
54 #include <linux/debugobjects.h>
55 #include <linux/kmemleak.h>
56 #include <linux/compaction.h>
57 #include <trace/events/kmem.h>
58 #include <linux/prefetch.h>
59 #include <linux/mm_inline.h>
60 #include <linux/migrate.h>
61 #include <linux/page_ext.h>
62 #include <linux/hugetlb.h>
63 #include <linux/sched/rt.h>
64 #include <linux/page_owner.h>
65 #include <linux/kthread.h>
67 #include <asm/sections.h>
68 #include <asm/tlbflush.h>
69 #include <asm/div64.h>
72 /* prevent >1 _updater_ of zone percpu pageset ->high and ->batch fields */
73 static DEFINE_MUTEX(pcp_batch_high_lock
);
74 #define MIN_PERCPU_PAGELIST_FRACTION (8)
76 #ifdef CONFIG_USE_PERCPU_NUMA_NODE_ID
77 DEFINE_PER_CPU(int, numa_node
);
78 EXPORT_PER_CPU_SYMBOL(numa_node
);
81 #ifdef CONFIG_HAVE_MEMORYLESS_NODES
83 * N.B., Do NOT reference the '_numa_mem_' per cpu variable directly.
84 * It will not be defined when CONFIG_HAVE_MEMORYLESS_NODES is not defined.
85 * Use the accessor functions set_numa_mem(), numa_mem_id() and cpu_to_mem()
86 * defined in <linux/topology.h>.
88 DEFINE_PER_CPU(int, _numa_mem_
); /* Kernel "local memory" node */
89 EXPORT_PER_CPU_SYMBOL(_numa_mem_
);
90 int _node_numa_mem_
[MAX_NUMNODES
];
94 * Array of node states.
96 nodemask_t node_states
[NR_NODE_STATES
] __read_mostly
= {
97 [N_POSSIBLE
] = NODE_MASK_ALL
,
98 [N_ONLINE
] = { { [0] = 1UL } },
100 [N_NORMAL_MEMORY
] = { { [0] = 1UL } },
101 #ifdef CONFIG_HIGHMEM
102 [N_HIGH_MEMORY
] = { { [0] = 1UL } },
104 #ifdef CONFIG_MOVABLE_NODE
105 [N_MEMORY
] = { { [0] = 1UL } },
107 [N_CPU
] = { { [0] = 1UL } },
110 EXPORT_SYMBOL(node_states
);
112 /* Protect totalram_pages and zone->managed_pages */
113 static DEFINE_SPINLOCK(managed_page_count_lock
);
115 unsigned long totalram_pages __read_mostly
;
116 unsigned long totalreserve_pages __read_mostly
;
117 unsigned long totalcma_pages __read_mostly
;
119 int percpu_pagelist_fraction
;
120 gfp_t gfp_allowed_mask __read_mostly
= GFP_BOOT_MASK
;
123 * A cached value of the page's pageblock's migratetype, used when the page is
124 * put on a pcplist. Used to avoid the pageblock migratetype lookup when
125 * freeing from pcplists in most cases, at the cost of possibly becoming stale.
126 * Also the migratetype set in the page does not necessarily match the pcplist
127 * index, e.g. page might have MIGRATE_CMA set but be on a pcplist with any
128 * other index - this ensures that it will be put on the correct CMA freelist.
130 static inline int get_pcppage_migratetype(struct page
*page
)
135 static inline void set_pcppage_migratetype(struct page
*page
, int migratetype
)
137 page
->index
= migratetype
;
140 #ifdef CONFIG_PM_SLEEP
142 * The following functions are used by the suspend/hibernate code to temporarily
143 * change gfp_allowed_mask in order to avoid using I/O during memory allocations
144 * while devices are suspended. To avoid races with the suspend/hibernate code,
145 * they should always be called with pm_mutex held (gfp_allowed_mask also should
146 * only be modified with pm_mutex held, unless the suspend/hibernate code is
147 * guaranteed not to run in parallel with that modification).
150 static gfp_t saved_gfp_mask
;
152 void pm_restore_gfp_mask(void)
154 WARN_ON(!mutex_is_locked(&pm_mutex
));
155 if (saved_gfp_mask
) {
156 gfp_allowed_mask
= saved_gfp_mask
;
161 void pm_restrict_gfp_mask(void)
163 WARN_ON(!mutex_is_locked(&pm_mutex
));
164 WARN_ON(saved_gfp_mask
);
165 saved_gfp_mask
= gfp_allowed_mask
;
166 gfp_allowed_mask
&= ~(__GFP_IO
| __GFP_FS
);
169 bool pm_suspended_storage(void)
171 if ((gfp_allowed_mask
& (__GFP_IO
| __GFP_FS
)) == (__GFP_IO
| __GFP_FS
))
175 #endif /* CONFIG_PM_SLEEP */
177 #ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
178 unsigned int pageblock_order __read_mostly
;
181 static void __free_pages_ok(struct page
*page
, unsigned int order
);
184 * results with 256, 32 in the lowmem_reserve sysctl:
185 * 1G machine -> (16M dma, 800M-16M normal, 1G-800M high)
186 * 1G machine -> (16M dma, 784M normal, 224M high)
187 * NORMAL allocation will leave 784M/256 of ram reserved in the ZONE_DMA
188 * HIGHMEM allocation will leave 224M/32 of ram reserved in ZONE_NORMAL
189 * HIGHMEM allocation will leave (224M+784M)/256 of ram reserved in ZONE_DMA
191 * TBD: should special case ZONE_DMA32 machines here - in those we normally
192 * don't need any ZONE_NORMAL reservation
194 int sysctl_lowmem_reserve_ratio
[MAX_NR_ZONES
-1] = {
195 #ifdef CONFIG_ZONE_DMA
198 #ifdef CONFIG_ZONE_DMA32
201 #ifdef CONFIG_HIGHMEM
207 EXPORT_SYMBOL(totalram_pages
);
209 static char * const zone_names
[MAX_NR_ZONES
] = {
210 #ifdef CONFIG_ZONE_DMA
213 #ifdef CONFIG_ZONE_DMA32
217 #ifdef CONFIG_HIGHMEM
221 #ifdef CONFIG_ZONE_DEVICE
226 char * const migratetype_names
[MIGRATE_TYPES
] = {
234 #ifdef CONFIG_MEMORY_ISOLATION
239 compound_page_dtor
* const compound_page_dtors
[] = {
242 #ifdef CONFIG_HUGETLB_PAGE
245 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
250 int min_free_kbytes
= 1024;
251 int user_min_free_kbytes
= -1;
252 int watermark_scale_factor
= 10;
254 static unsigned long __meminitdata nr_kernel_pages
;
255 static unsigned long __meminitdata nr_all_pages
;
256 static unsigned long __meminitdata dma_reserve
;
258 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
259 static unsigned long __meminitdata arch_zone_lowest_possible_pfn
[MAX_NR_ZONES
];
260 static unsigned long __meminitdata arch_zone_highest_possible_pfn
[MAX_NR_ZONES
];
261 static unsigned long __initdata required_kernelcore
;
262 static unsigned long __initdata required_movablecore
;
263 static unsigned long __meminitdata zone_movable_pfn
[MAX_NUMNODES
];
264 static bool mirrored_kernelcore
;
266 /* movable_zone is the "real" zone pages in ZONE_MOVABLE are taken from */
268 EXPORT_SYMBOL(movable_zone
);
269 #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
272 int nr_node_ids __read_mostly
= MAX_NUMNODES
;
273 int nr_online_nodes __read_mostly
= 1;
274 EXPORT_SYMBOL(nr_node_ids
);
275 EXPORT_SYMBOL(nr_online_nodes
);
278 int page_group_by_mobility_disabled __read_mostly
;
280 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
281 static inline void reset_deferred_meminit(pg_data_t
*pgdat
)
283 pgdat
->first_deferred_pfn
= ULONG_MAX
;
286 /* Returns true if the struct page for the pfn is uninitialised */
287 static inline bool __meminit
early_page_uninitialised(unsigned long pfn
)
289 if (pfn
>= NODE_DATA(early_pfn_to_nid(pfn
))->first_deferred_pfn
)
295 static inline bool early_page_nid_uninitialised(unsigned long pfn
, int nid
)
297 if (pfn
>= NODE_DATA(nid
)->first_deferred_pfn
)
304 * Returns false when the remaining initialisation should be deferred until
305 * later in the boot cycle when it can be parallelised.
307 static inline bool update_defer_init(pg_data_t
*pgdat
,
308 unsigned long pfn
, unsigned long zone_end
,
309 unsigned long *nr_initialised
)
311 unsigned long max_initialise
;
313 /* Always populate low zones for address-contrained allocations */
314 if (zone_end
< pgdat_end_pfn(pgdat
))
317 * Initialise at least 2G of a node but also take into account that
318 * two large system hashes that can take up 1GB for 0.25TB/node.
320 max_initialise
= max(2UL << (30 - PAGE_SHIFT
),
321 (pgdat
->node_spanned_pages
>> 8));
324 if ((*nr_initialised
> max_initialise
) &&
325 (pfn
& (PAGES_PER_SECTION
- 1)) == 0) {
326 pgdat
->first_deferred_pfn
= pfn
;
333 static inline void reset_deferred_meminit(pg_data_t
*pgdat
)
337 static inline bool early_page_uninitialised(unsigned long pfn
)
342 static inline bool early_page_nid_uninitialised(unsigned long pfn
, int nid
)
347 static inline bool update_defer_init(pg_data_t
*pgdat
,
348 unsigned long pfn
, unsigned long zone_end
,
349 unsigned long *nr_initialised
)
356 void set_pageblock_migratetype(struct page
*page
, int migratetype
)
358 if (unlikely(page_group_by_mobility_disabled
&&
359 migratetype
< MIGRATE_PCPTYPES
))
360 migratetype
= MIGRATE_UNMOVABLE
;
362 set_pageblock_flags_group(page
, (unsigned long)migratetype
,
363 PB_migrate
, PB_migrate_end
);
366 #ifdef CONFIG_DEBUG_VM
367 static int page_outside_zone_boundaries(struct zone
*zone
, struct page
*page
)
371 unsigned long pfn
= page_to_pfn(page
);
372 unsigned long sp
, start_pfn
;
375 seq
= zone_span_seqbegin(zone
);
376 start_pfn
= zone
->zone_start_pfn
;
377 sp
= zone
->spanned_pages
;
378 if (!zone_spans_pfn(zone
, pfn
))
380 } while (zone_span_seqretry(zone
, seq
));
383 pr_err("page 0x%lx outside node %d zone %s [ 0x%lx - 0x%lx ]\n",
384 pfn
, zone_to_nid(zone
), zone
->name
,
385 start_pfn
, start_pfn
+ sp
);
390 static int page_is_consistent(struct zone
*zone
, struct page
*page
)
392 if (!pfn_valid_within(page_to_pfn(page
)))
394 if (zone
!= page_zone(page
))
400 * Temporary debugging check for pages not lying within a given zone.
402 static int bad_range(struct zone
*zone
, struct page
*page
)
404 if (page_outside_zone_boundaries(zone
, page
))
406 if (!page_is_consistent(zone
, page
))
412 static inline int bad_range(struct zone
*zone
, struct page
*page
)
418 static void bad_page(struct page
*page
, const char *reason
,
419 unsigned long bad_flags
)
421 static unsigned long resume
;
422 static unsigned long nr_shown
;
423 static unsigned long nr_unshown
;
425 /* Don't complain about poisoned pages */
426 if (PageHWPoison(page
)) {
427 page_mapcount_reset(page
); /* remove PageBuddy */
432 * Allow a burst of 60 reports, then keep quiet for that minute;
433 * or allow a steady drip of one report per second.
435 if (nr_shown
== 60) {
436 if (time_before(jiffies
, resume
)) {
442 "BUG: Bad page state: %lu messages suppressed\n",
449 resume
= jiffies
+ 60 * HZ
;
451 pr_alert("BUG: Bad page state in process %s pfn:%05lx\n",
452 current
->comm
, page_to_pfn(page
));
453 __dump_page(page
, reason
);
454 bad_flags
&= page
->flags
;
456 pr_alert("bad because of flags: %#lx(%pGp)\n",
457 bad_flags
, &bad_flags
);
458 dump_page_owner(page
);
463 /* Leave bad fields for debug, except PageBuddy could make trouble */
464 page_mapcount_reset(page
); /* remove PageBuddy */
465 add_taint(TAINT_BAD_PAGE
, LOCKDEP_NOW_UNRELIABLE
);
469 * Higher-order pages are called "compound pages". They are structured thusly:
471 * The first PAGE_SIZE page is called the "head page" and have PG_head set.
473 * The remaining PAGE_SIZE pages are called "tail pages". PageTail() is encoded
474 * in bit 0 of page->compound_head. The rest of bits is pointer to head page.
476 * The first tail page's ->compound_dtor holds the offset in array of compound
477 * page destructors. See compound_page_dtors.
479 * The first tail page's ->compound_order holds the order of allocation.
480 * This usage means that zero-order pages may not be compound.
483 void free_compound_page(struct page
*page
)
485 __free_pages_ok(page
, compound_order(page
));
488 void prep_compound_page(struct page
*page
, unsigned int order
)
491 int nr_pages
= 1 << order
;
493 set_compound_page_dtor(page
, COMPOUND_PAGE_DTOR
);
494 set_compound_order(page
, order
);
496 for (i
= 1; i
< nr_pages
; i
++) {
497 struct page
*p
= page
+ i
;
498 set_page_count(p
, 0);
499 p
->mapping
= TAIL_MAPPING
;
500 set_compound_head(p
, page
);
502 atomic_set(compound_mapcount_ptr(page
), -1);
505 #ifdef CONFIG_DEBUG_PAGEALLOC
506 unsigned int _debug_guardpage_minorder
;
507 bool _debug_pagealloc_enabled __read_mostly
508 = IS_ENABLED(CONFIG_DEBUG_PAGEALLOC_ENABLE_DEFAULT
);
509 EXPORT_SYMBOL(_debug_pagealloc_enabled
);
510 bool _debug_guardpage_enabled __read_mostly
;
512 static int __init
early_debug_pagealloc(char *buf
)
517 if (strcmp(buf
, "on") == 0)
518 _debug_pagealloc_enabled
= true;
520 if (strcmp(buf
, "off") == 0)
521 _debug_pagealloc_enabled
= false;
525 early_param("debug_pagealloc", early_debug_pagealloc
);
527 static bool need_debug_guardpage(void)
529 /* If we don't use debug_pagealloc, we don't need guard page */
530 if (!debug_pagealloc_enabled())
536 static void init_debug_guardpage(void)
538 if (!debug_pagealloc_enabled())
541 _debug_guardpage_enabled
= true;
544 struct page_ext_operations debug_guardpage_ops
= {
545 .need
= need_debug_guardpage
,
546 .init
= init_debug_guardpage
,
549 static int __init
debug_guardpage_minorder_setup(char *buf
)
553 if (kstrtoul(buf
, 10, &res
) < 0 || res
> MAX_ORDER
/ 2) {
554 pr_err("Bad debug_guardpage_minorder value\n");
557 _debug_guardpage_minorder
= res
;
558 pr_info("Setting debug_guardpage_minorder to %lu\n", res
);
561 __setup("debug_guardpage_minorder=", debug_guardpage_minorder_setup
);
563 static inline void set_page_guard(struct zone
*zone
, struct page
*page
,
564 unsigned int order
, int migratetype
)
566 struct page_ext
*page_ext
;
568 if (!debug_guardpage_enabled())
571 page_ext
= lookup_page_ext(page
);
572 __set_bit(PAGE_EXT_DEBUG_GUARD
, &page_ext
->flags
);
574 INIT_LIST_HEAD(&page
->lru
);
575 set_page_private(page
, order
);
576 /* Guard pages are not available for any usage */
577 __mod_zone_freepage_state(zone
, -(1 << order
), migratetype
);
580 static inline void clear_page_guard(struct zone
*zone
, struct page
*page
,
581 unsigned int order
, int migratetype
)
583 struct page_ext
*page_ext
;
585 if (!debug_guardpage_enabled())
588 page_ext
= lookup_page_ext(page
);
589 __clear_bit(PAGE_EXT_DEBUG_GUARD
, &page_ext
->flags
);
591 set_page_private(page
, 0);
592 if (!is_migrate_isolate(migratetype
))
593 __mod_zone_freepage_state(zone
, (1 << order
), migratetype
);
596 struct page_ext_operations debug_guardpage_ops
= { NULL
, };
597 static inline void set_page_guard(struct zone
*zone
, struct page
*page
,
598 unsigned int order
, int migratetype
) {}
599 static inline void clear_page_guard(struct zone
*zone
, struct page
*page
,
600 unsigned int order
, int migratetype
) {}
603 static inline void set_page_order(struct page
*page
, unsigned int order
)
605 set_page_private(page
, order
);
606 __SetPageBuddy(page
);
609 static inline void rmv_page_order(struct page
*page
)
611 __ClearPageBuddy(page
);
612 set_page_private(page
, 0);
616 * This function checks whether a page is free && is the buddy
617 * we can do coalesce a page and its buddy if
618 * (a) the buddy is not in a hole &&
619 * (b) the buddy is in the buddy system &&
620 * (c) a page and its buddy have the same order &&
621 * (d) a page and its buddy are in the same zone.
623 * For recording whether a page is in the buddy system, we set ->_mapcount
624 * PAGE_BUDDY_MAPCOUNT_VALUE.
625 * Setting, clearing, and testing _mapcount PAGE_BUDDY_MAPCOUNT_VALUE is
626 * serialized by zone->lock.
628 * For recording page's order, we use page_private(page).
630 static inline int page_is_buddy(struct page
*page
, struct page
*buddy
,
633 if (!pfn_valid_within(page_to_pfn(buddy
)))
636 if (page_is_guard(buddy
) && page_order(buddy
) == order
) {
637 if (page_zone_id(page
) != page_zone_id(buddy
))
640 VM_BUG_ON_PAGE(page_count(buddy
) != 0, buddy
);
645 if (PageBuddy(buddy
) && page_order(buddy
) == order
) {
647 * zone check is done late to avoid uselessly
648 * calculating zone/node ids for pages that could
651 if (page_zone_id(page
) != page_zone_id(buddy
))
654 VM_BUG_ON_PAGE(page_count(buddy
) != 0, buddy
);
662 * Freeing function for a buddy system allocator.
664 * The concept of a buddy system is to maintain direct-mapped table
665 * (containing bit values) for memory blocks of various "orders".
666 * The bottom level table contains the map for the smallest allocatable
667 * units of memory (here, pages), and each level above it describes
668 * pairs of units from the levels below, hence, "buddies".
669 * At a high level, all that happens here is marking the table entry
670 * at the bottom level available, and propagating the changes upward
671 * as necessary, plus some accounting needed to play nicely with other
672 * parts of the VM system.
673 * At each level, we keep a list of pages, which are heads of continuous
674 * free pages of length of (1 << order) and marked with _mapcount
675 * PAGE_BUDDY_MAPCOUNT_VALUE. Page's order is recorded in page_private(page)
677 * So when we are allocating or freeing one, we can derive the state of the
678 * other. That is, if we allocate a small block, and both were
679 * free, the remainder of the region must be split into blocks.
680 * If a block is freed, and its buddy is also free, then this
681 * triggers coalescing into a block of larger size.
686 static inline void __free_one_page(struct page
*page
,
688 struct zone
*zone
, unsigned int order
,
691 unsigned long page_idx
;
692 unsigned long combined_idx
;
693 unsigned long uninitialized_var(buddy_idx
);
695 unsigned int max_order
;
697 max_order
= min_t(unsigned int, MAX_ORDER
, pageblock_order
+ 1);
699 VM_BUG_ON(!zone_is_initialized(zone
));
700 VM_BUG_ON_PAGE(page
->flags
& PAGE_FLAGS_CHECK_AT_PREP
, page
);
702 VM_BUG_ON(migratetype
== -1);
703 if (likely(!is_migrate_isolate(migratetype
)))
704 __mod_zone_freepage_state(zone
, 1 << order
, migratetype
);
706 page_idx
= pfn
& ((1 << MAX_ORDER
) - 1);
708 VM_BUG_ON_PAGE(page_idx
& ((1 << order
) - 1), page
);
709 VM_BUG_ON_PAGE(bad_range(zone
, page
), page
);
712 while (order
< max_order
- 1) {
713 buddy_idx
= __find_buddy_index(page_idx
, order
);
714 buddy
= page
+ (buddy_idx
- page_idx
);
715 if (!page_is_buddy(page
, buddy
, order
))
718 * Our buddy is free or it is CONFIG_DEBUG_PAGEALLOC guard page,
719 * merge with it and move up one order.
721 if (page_is_guard(buddy
)) {
722 clear_page_guard(zone
, buddy
, order
, migratetype
);
724 list_del(&buddy
->lru
);
725 zone
->free_area
[order
].nr_free
--;
726 rmv_page_order(buddy
);
728 combined_idx
= buddy_idx
& page_idx
;
729 page
= page
+ (combined_idx
- page_idx
);
730 page_idx
= combined_idx
;
733 if (max_order
< MAX_ORDER
) {
734 /* If we are here, it means order is >= pageblock_order.
735 * We want to prevent merge between freepages on isolate
736 * pageblock and normal pageblock. Without this, pageblock
737 * isolation could cause incorrect freepage or CMA accounting.
739 * We don't want to hit this code for the more frequent
742 if (unlikely(has_isolate_pageblock(zone
))) {
745 buddy_idx
= __find_buddy_index(page_idx
, order
);
746 buddy
= page
+ (buddy_idx
- page_idx
);
747 buddy_mt
= get_pageblock_migratetype(buddy
);
749 if (migratetype
!= buddy_mt
750 && (is_migrate_isolate(migratetype
) ||
751 is_migrate_isolate(buddy_mt
)))
755 goto continue_merging
;
759 set_page_order(page
, order
);
762 * If this is not the largest possible page, check if the buddy
763 * of the next-highest order is free. If it is, it's possible
764 * that pages are being freed that will coalesce soon. In case,
765 * that is happening, add the free page to the tail of the list
766 * so it's less likely to be used soon and more likely to be merged
767 * as a higher order page
769 if ((order
< MAX_ORDER
-2) && pfn_valid_within(page_to_pfn(buddy
))) {
770 struct page
*higher_page
, *higher_buddy
;
771 combined_idx
= buddy_idx
& page_idx
;
772 higher_page
= page
+ (combined_idx
- page_idx
);
773 buddy_idx
= __find_buddy_index(combined_idx
, order
+ 1);
774 higher_buddy
= higher_page
+ (buddy_idx
- combined_idx
);
775 if (page_is_buddy(higher_page
, higher_buddy
, order
+ 1)) {
776 list_add_tail(&page
->lru
,
777 &zone
->free_area
[order
].free_list
[migratetype
]);
782 list_add(&page
->lru
, &zone
->free_area
[order
].free_list
[migratetype
]);
784 zone
->free_area
[order
].nr_free
++;
787 static inline int free_pages_check(struct page
*page
)
789 const char *bad_reason
= NULL
;
790 unsigned long bad_flags
= 0;
792 if (unlikely(atomic_read(&page
->_mapcount
) != -1))
793 bad_reason
= "nonzero mapcount";
794 if (unlikely(page
->mapping
!= NULL
))
795 bad_reason
= "non-NULL mapping";
796 if (unlikely(page_ref_count(page
) != 0))
797 bad_reason
= "nonzero _refcount";
798 if (unlikely(page
->flags
& PAGE_FLAGS_CHECK_AT_FREE
)) {
799 bad_reason
= "PAGE_FLAGS_CHECK_AT_FREE flag(s) set";
800 bad_flags
= PAGE_FLAGS_CHECK_AT_FREE
;
803 if (unlikely(page
->mem_cgroup
))
804 bad_reason
= "page still charged to cgroup";
806 if (unlikely(bad_reason
)) {
807 bad_page(page
, bad_reason
, bad_flags
);
810 page_cpupid_reset_last(page
);
811 if (page
->flags
& PAGE_FLAGS_CHECK_AT_PREP
)
812 page
->flags
&= ~PAGE_FLAGS_CHECK_AT_PREP
;
817 * Frees a number of pages from the PCP lists
818 * Assumes all pages on list are in same zone, and of same order.
819 * count is the number of pages to free.
821 * If the zone was previously in an "all pages pinned" state then look to
822 * see if this freeing clears that state.
824 * And clear the zone's pages_scanned counter, to hold off the "all pages are
825 * pinned" detection logic.
827 static void free_pcppages_bulk(struct zone
*zone
, int count
,
828 struct per_cpu_pages
*pcp
)
833 unsigned long nr_scanned
;
834 bool isolated_pageblocks
;
836 spin_lock(&zone
->lock
);
837 isolated_pageblocks
= has_isolate_pageblock(zone
);
838 nr_scanned
= zone_page_state(zone
, NR_PAGES_SCANNED
);
840 __mod_zone_page_state(zone
, NR_PAGES_SCANNED
, -nr_scanned
);
844 struct list_head
*list
;
847 * Remove pages from lists in a round-robin fashion. A
848 * batch_free count is maintained that is incremented when an
849 * empty list is encountered. This is so more pages are freed
850 * off fuller lists instead of spinning excessively around empty
855 if (++migratetype
== MIGRATE_PCPTYPES
)
857 list
= &pcp
->lists
[migratetype
];
858 } while (list_empty(list
));
860 /* This is the only non-empty list. Free them all. */
861 if (batch_free
== MIGRATE_PCPTYPES
)
862 batch_free
= to_free
;
865 int mt
; /* migratetype of the to-be-freed page */
867 page
= list_last_entry(list
, struct page
, lru
);
868 /* must delete as __free_one_page list manipulates */
869 list_del(&page
->lru
);
871 mt
= get_pcppage_migratetype(page
);
872 /* MIGRATE_ISOLATE page should not go to pcplists */
873 VM_BUG_ON_PAGE(is_migrate_isolate(mt
), page
);
874 /* Pageblock could have been isolated meanwhile */
875 if (unlikely(isolated_pageblocks
))
876 mt
= get_pageblock_migratetype(page
);
878 __free_one_page(page
, page_to_pfn(page
), zone
, 0, mt
);
879 trace_mm_page_pcpu_drain(page
, 0, mt
);
880 } while (--to_free
&& --batch_free
&& !list_empty(list
));
882 spin_unlock(&zone
->lock
);
885 static void free_one_page(struct zone
*zone
,
886 struct page
*page
, unsigned long pfn
,
890 unsigned long nr_scanned
;
891 spin_lock(&zone
->lock
);
892 nr_scanned
= zone_page_state(zone
, NR_PAGES_SCANNED
);
894 __mod_zone_page_state(zone
, NR_PAGES_SCANNED
, -nr_scanned
);
896 if (unlikely(has_isolate_pageblock(zone
) ||
897 is_migrate_isolate(migratetype
))) {
898 migratetype
= get_pfnblock_migratetype(page
, pfn
);
900 __free_one_page(page
, pfn
, zone
, order
, migratetype
);
901 spin_unlock(&zone
->lock
);
904 static int free_tail_pages_check(struct page
*head_page
, struct page
*page
)
909 * We rely page->lru.next never has bit 0 set, unless the page
910 * is PageTail(). Let's make sure that's true even for poisoned ->lru.
912 BUILD_BUG_ON((unsigned long)LIST_POISON1
& 1);
914 if (!IS_ENABLED(CONFIG_DEBUG_VM
)) {
918 switch (page
- head_page
) {
920 /* the first tail page: ->mapping is compound_mapcount() */
921 if (unlikely(compound_mapcount(page
))) {
922 bad_page(page
, "nonzero compound_mapcount", 0);
928 * the second tail page: ->mapping is
929 * page_deferred_list().next -- ignore value.
933 if (page
->mapping
!= TAIL_MAPPING
) {
934 bad_page(page
, "corrupted mapping in tail page", 0);
939 if (unlikely(!PageTail(page
))) {
940 bad_page(page
, "PageTail not set", 0);
943 if (unlikely(compound_head(page
) != head_page
)) {
944 bad_page(page
, "compound_head not consistent", 0);
949 page
->mapping
= NULL
;
950 clear_compound_head(page
);
954 static void __meminit
__init_single_page(struct page
*page
, unsigned long pfn
,
955 unsigned long zone
, int nid
)
957 set_page_links(page
, zone
, nid
, pfn
);
958 init_page_count(page
);
959 page_mapcount_reset(page
);
960 page_cpupid_reset_last(page
);
962 INIT_LIST_HEAD(&page
->lru
);
963 #ifdef WANT_PAGE_VIRTUAL
964 /* The shift won't overflow because ZONE_NORMAL is below 4G. */
965 if (!is_highmem_idx(zone
))
966 set_page_address(page
, __va(pfn
<< PAGE_SHIFT
));
970 static void __meminit
__init_single_pfn(unsigned long pfn
, unsigned long zone
,
973 return __init_single_page(pfn_to_page(pfn
), pfn
, zone
, nid
);
976 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
977 static void init_reserved_page(unsigned long pfn
)
982 if (!early_page_uninitialised(pfn
))
985 nid
= early_pfn_to_nid(pfn
);
986 pgdat
= NODE_DATA(nid
);
988 for (zid
= 0; zid
< MAX_NR_ZONES
; zid
++) {
989 struct zone
*zone
= &pgdat
->node_zones
[zid
];
991 if (pfn
>= zone
->zone_start_pfn
&& pfn
< zone_end_pfn(zone
))
994 __init_single_pfn(pfn
, zid
, nid
);
997 static inline void init_reserved_page(unsigned long pfn
)
1000 #endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */
1003 * Initialised pages do not have PageReserved set. This function is
1004 * called for each range allocated by the bootmem allocator and
1005 * marks the pages PageReserved. The remaining valid pages are later
1006 * sent to the buddy page allocator.
1008 void __meminit
reserve_bootmem_region(unsigned long start
, unsigned long end
)
1010 unsigned long start_pfn
= PFN_DOWN(start
);
1011 unsigned long end_pfn
= PFN_UP(end
);
1013 for (; start_pfn
< end_pfn
; start_pfn
++) {
1014 if (pfn_valid(start_pfn
)) {
1015 struct page
*page
= pfn_to_page(start_pfn
);
1017 init_reserved_page(start_pfn
);
1019 /* Avoid false-positive PageTail() */
1020 INIT_LIST_HEAD(&page
->lru
);
1022 SetPageReserved(page
);
1027 static bool free_pages_prepare(struct page
*page
, unsigned int order
)
1031 VM_BUG_ON_PAGE(PageTail(page
), page
);
1033 trace_mm_page_free(page
, order
);
1034 kmemcheck_free_shadow(page
, order
);
1035 kasan_free_pages(page
, order
);
1038 * Check tail pages before head page information is cleared to
1039 * avoid checking PageCompound for order-0 pages.
1041 if (unlikely(order
)) {
1042 bool compound
= PageCompound(page
);
1045 VM_BUG_ON_PAGE(compound
&& compound_order(page
) != order
, page
);
1047 for (i
= 1; i
< (1 << order
); i
++) {
1049 bad
+= free_tail_pages_check(page
, page
+ i
);
1050 bad
+= free_pages_check(page
+ i
);
1053 if (PageAnonHead(page
))
1054 page
->mapping
= NULL
;
1055 bad
+= free_pages_check(page
);
1059 reset_page_owner(page
, order
);
1061 if (!PageHighMem(page
)) {
1062 debug_check_no_locks_freed(page_address(page
),
1063 PAGE_SIZE
<< order
);
1064 debug_check_no_obj_freed(page_address(page
),
1065 PAGE_SIZE
<< order
);
1067 arch_free_page(page
, order
);
1068 kernel_poison_pages(page
, 1 << order
, 0);
1069 kernel_map_pages(page
, 1 << order
, 0);
1074 static void __free_pages_ok(struct page
*page
, unsigned int order
)
1076 unsigned long flags
;
1078 unsigned long pfn
= page_to_pfn(page
);
1080 if (!free_pages_prepare(page
, order
))
1083 migratetype
= get_pfnblock_migratetype(page
, pfn
);
1084 local_irq_save(flags
);
1085 __count_vm_events(PGFREE
, 1 << order
);
1086 free_one_page(page_zone(page
), page
, pfn
, order
, migratetype
);
1087 local_irq_restore(flags
);
1090 static void __init
__free_pages_boot_core(struct page
*page
, unsigned int order
)
1092 unsigned int nr_pages
= 1 << order
;
1093 struct page
*p
= page
;
1097 for (loop
= 0; loop
< (nr_pages
- 1); loop
++, p
++) {
1099 __ClearPageReserved(p
);
1100 set_page_count(p
, 0);
1102 __ClearPageReserved(p
);
1103 set_page_count(p
, 0);
1105 page_zone(page
)->managed_pages
+= nr_pages
;
1106 set_page_refcounted(page
);
1107 __free_pages(page
, order
);
1110 #if defined(CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID) || \
1111 defined(CONFIG_HAVE_MEMBLOCK_NODE_MAP)
1113 static struct mminit_pfnnid_cache early_pfnnid_cache __meminitdata
;
1115 int __meminit
early_pfn_to_nid(unsigned long pfn
)
1117 static DEFINE_SPINLOCK(early_pfn_lock
);
1120 spin_lock(&early_pfn_lock
);
1121 nid
= __early_pfn_to_nid(pfn
, &early_pfnnid_cache
);
1124 spin_unlock(&early_pfn_lock
);
1130 #ifdef CONFIG_NODES_SPAN_OTHER_NODES
1131 static inline bool __meminit
meminit_pfn_in_nid(unsigned long pfn
, int node
,
1132 struct mminit_pfnnid_cache
*state
)
1136 nid
= __early_pfn_to_nid(pfn
, state
);
1137 if (nid
>= 0 && nid
!= node
)
1142 /* Only safe to use early in boot when initialisation is single-threaded */
1143 static inline bool __meminit
early_pfn_in_nid(unsigned long pfn
, int node
)
1145 return meminit_pfn_in_nid(pfn
, node
, &early_pfnnid_cache
);
1150 static inline bool __meminit
early_pfn_in_nid(unsigned long pfn
, int node
)
1154 static inline bool __meminit
meminit_pfn_in_nid(unsigned long pfn
, int node
,
1155 struct mminit_pfnnid_cache
*state
)
1162 void __init
__free_pages_bootmem(struct page
*page
, unsigned long pfn
,
1165 if (early_page_uninitialised(pfn
))
1167 return __free_pages_boot_core(page
, order
);
1171 * Check that the whole (or subset of) a pageblock given by the interval of
1172 * [start_pfn, end_pfn) is valid and within the same zone, before scanning it
1173 * with the migration of free compaction scanner. The scanners then need to
1174 * use only pfn_valid_within() check for arches that allow holes within
1177 * Return struct page pointer of start_pfn, or NULL if checks were not passed.
1179 * It's possible on some configurations to have a setup like node0 node1 node0
1180 * i.e. it's possible that all pages within a zones range of pages do not
1181 * belong to a single zone. We assume that a border between node0 and node1
1182 * can occur within a single pageblock, but not a node0 node1 node0
1183 * interleaving within a single pageblock. It is therefore sufficient to check
1184 * the first and last page of a pageblock and avoid checking each individual
1185 * page in a pageblock.
1187 struct page
*__pageblock_pfn_to_page(unsigned long start_pfn
,
1188 unsigned long end_pfn
, struct zone
*zone
)
1190 struct page
*start_page
;
1191 struct page
*end_page
;
1193 /* end_pfn is one past the range we are checking */
1196 if (!pfn_valid(start_pfn
) || !pfn_valid(end_pfn
))
1199 start_page
= pfn_to_page(start_pfn
);
1201 if (page_zone(start_page
) != zone
)
1204 end_page
= pfn_to_page(end_pfn
);
1206 /* This gives a shorter code than deriving page_zone(end_page) */
1207 if (page_zone_id(start_page
) != page_zone_id(end_page
))
1213 void set_zone_contiguous(struct zone
*zone
)
1215 unsigned long block_start_pfn
= zone
->zone_start_pfn
;
1216 unsigned long block_end_pfn
;
1218 block_end_pfn
= ALIGN(block_start_pfn
+ 1, pageblock_nr_pages
);
1219 for (; block_start_pfn
< zone_end_pfn(zone
);
1220 block_start_pfn
= block_end_pfn
,
1221 block_end_pfn
+= pageblock_nr_pages
) {
1223 block_end_pfn
= min(block_end_pfn
, zone_end_pfn(zone
));
1225 if (!__pageblock_pfn_to_page(block_start_pfn
,
1226 block_end_pfn
, zone
))
1230 /* We confirm that there is no hole */
1231 zone
->contiguous
= true;
1234 void clear_zone_contiguous(struct zone
*zone
)
1236 zone
->contiguous
= false;
1239 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
1240 static void __init
deferred_free_range(struct page
*page
,
1241 unsigned long pfn
, int nr_pages
)
1248 /* Free a large naturally-aligned chunk if possible */
1249 if (nr_pages
== MAX_ORDER_NR_PAGES
&&
1250 (pfn
& (MAX_ORDER_NR_PAGES
-1)) == 0) {
1251 set_pageblock_migratetype(page
, MIGRATE_MOVABLE
);
1252 __free_pages_boot_core(page
, MAX_ORDER
-1);
1256 for (i
= 0; i
< nr_pages
; i
++, page
++)
1257 __free_pages_boot_core(page
, 0);
1260 /* Completion tracking for deferred_init_memmap() threads */
1261 static atomic_t pgdat_init_n_undone __initdata
;
1262 static __initdata
DECLARE_COMPLETION(pgdat_init_all_done_comp
);
1264 static inline void __init
pgdat_init_report_one_done(void)
1266 if (atomic_dec_and_test(&pgdat_init_n_undone
))
1267 complete(&pgdat_init_all_done_comp
);
1270 /* Initialise remaining memory on a node */
1271 static int __init
deferred_init_memmap(void *data
)
1273 pg_data_t
*pgdat
= data
;
1274 int nid
= pgdat
->node_id
;
1275 struct mminit_pfnnid_cache nid_init_state
= { };
1276 unsigned long start
= jiffies
;
1277 unsigned long nr_pages
= 0;
1278 unsigned long walk_start
, walk_end
;
1281 unsigned long first_init_pfn
= pgdat
->first_deferred_pfn
;
1282 const struct cpumask
*cpumask
= cpumask_of_node(pgdat
->node_id
);
1284 if (first_init_pfn
== ULONG_MAX
) {
1285 pgdat_init_report_one_done();
1289 /* Bind memory initialisation thread to a local node if possible */
1290 if (!cpumask_empty(cpumask
))
1291 set_cpus_allowed_ptr(current
, cpumask
);
1293 /* Sanity check boundaries */
1294 BUG_ON(pgdat
->first_deferred_pfn
< pgdat
->node_start_pfn
);
1295 BUG_ON(pgdat
->first_deferred_pfn
> pgdat_end_pfn(pgdat
));
1296 pgdat
->first_deferred_pfn
= ULONG_MAX
;
1298 /* Only the highest zone is deferred so find it */
1299 for (zid
= 0; zid
< MAX_NR_ZONES
; zid
++) {
1300 zone
= pgdat
->node_zones
+ zid
;
1301 if (first_init_pfn
< zone_end_pfn(zone
))
1305 for_each_mem_pfn_range(i
, nid
, &walk_start
, &walk_end
, NULL
) {
1306 unsigned long pfn
, end_pfn
;
1307 struct page
*page
= NULL
;
1308 struct page
*free_base_page
= NULL
;
1309 unsigned long free_base_pfn
= 0;
1312 end_pfn
= min(walk_end
, zone_end_pfn(zone
));
1313 pfn
= first_init_pfn
;
1314 if (pfn
< walk_start
)
1316 if (pfn
< zone
->zone_start_pfn
)
1317 pfn
= zone
->zone_start_pfn
;
1319 for (; pfn
< end_pfn
; pfn
++) {
1320 if (!pfn_valid_within(pfn
))
1324 * Ensure pfn_valid is checked every
1325 * MAX_ORDER_NR_PAGES for memory holes
1327 if ((pfn
& (MAX_ORDER_NR_PAGES
- 1)) == 0) {
1328 if (!pfn_valid(pfn
)) {
1334 if (!meminit_pfn_in_nid(pfn
, nid
, &nid_init_state
)) {
1339 /* Minimise pfn page lookups and scheduler checks */
1340 if (page
&& (pfn
& (MAX_ORDER_NR_PAGES
- 1)) != 0) {
1343 nr_pages
+= nr_to_free
;
1344 deferred_free_range(free_base_page
,
1345 free_base_pfn
, nr_to_free
);
1346 free_base_page
= NULL
;
1347 free_base_pfn
= nr_to_free
= 0;
1349 page
= pfn_to_page(pfn
);
1354 VM_BUG_ON(page_zone(page
) != zone
);
1358 __init_single_page(page
, pfn
, zid
, nid
);
1359 if (!free_base_page
) {
1360 free_base_page
= page
;
1361 free_base_pfn
= pfn
;
1366 /* Where possible, batch up pages for a single free */
1369 /* Free the current block of pages to allocator */
1370 nr_pages
+= nr_to_free
;
1371 deferred_free_range(free_base_page
, free_base_pfn
,
1373 free_base_page
= NULL
;
1374 free_base_pfn
= nr_to_free
= 0;
1377 first_init_pfn
= max(end_pfn
, first_init_pfn
);
1380 /* Sanity check that the next zone really is unpopulated */
1381 WARN_ON(++zid
< MAX_NR_ZONES
&& populated_zone(++zone
));
1383 pr_info("node %d initialised, %lu pages in %ums\n", nid
, nr_pages
,
1384 jiffies_to_msecs(jiffies
- start
));
1386 pgdat_init_report_one_done();
1389 #endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */
1391 void __init
page_alloc_init_late(void)
1395 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
1398 /* There will be num_node_state(N_MEMORY) threads */
1399 atomic_set(&pgdat_init_n_undone
, num_node_state(N_MEMORY
));
1400 for_each_node_state(nid
, N_MEMORY
) {
1401 kthread_run(deferred_init_memmap
, NODE_DATA(nid
), "pgdatinit%d", nid
);
1404 /* Block until all are initialised */
1405 wait_for_completion(&pgdat_init_all_done_comp
);
1407 /* Reinit limits that are based on free pages after the kernel is up */
1408 files_maxfiles_init();
1411 for_each_populated_zone(zone
)
1412 set_zone_contiguous(zone
);
1416 /* Free whole pageblock and set its migration type to MIGRATE_CMA. */
1417 void __init
init_cma_reserved_pageblock(struct page
*page
)
1419 unsigned i
= pageblock_nr_pages
;
1420 struct page
*p
= page
;
1423 __ClearPageReserved(p
);
1424 set_page_count(p
, 0);
1427 set_pageblock_migratetype(page
, MIGRATE_CMA
);
1429 if (pageblock_order
>= MAX_ORDER
) {
1430 i
= pageblock_nr_pages
;
1433 set_page_refcounted(p
);
1434 __free_pages(p
, MAX_ORDER
- 1);
1435 p
+= MAX_ORDER_NR_PAGES
;
1436 } while (i
-= MAX_ORDER_NR_PAGES
);
1438 set_page_refcounted(page
);
1439 __free_pages(page
, pageblock_order
);
1442 adjust_managed_page_count(page
, pageblock_nr_pages
);
1447 * The order of subdivision here is critical for the IO subsystem.
1448 * Please do not alter this order without good reasons and regression
1449 * testing. Specifically, as large blocks of memory are subdivided,
1450 * the order in which smaller blocks are delivered depends on the order
1451 * they're subdivided in this function. This is the primary factor
1452 * influencing the order in which pages are delivered to the IO
1453 * subsystem according to empirical testing, and this is also justified
1454 * by considering the behavior of a buddy system containing a single
1455 * large block of memory acted on by a series of small allocations.
1456 * This behavior is a critical factor in sglist merging's success.
1460 static inline void expand(struct zone
*zone
, struct page
*page
,
1461 int low
, int high
, struct free_area
*area
,
1464 unsigned long size
= 1 << high
;
1466 while (high
> low
) {
1470 VM_BUG_ON_PAGE(bad_range(zone
, &page
[size
]), &page
[size
]);
1472 if (IS_ENABLED(CONFIG_DEBUG_PAGEALLOC
) &&
1473 debug_guardpage_enabled() &&
1474 high
< debug_guardpage_minorder()) {
1476 * Mark as guard pages (or page), that will allow to
1477 * merge back to allocator when buddy will be freed.
1478 * Corresponding page table entries will not be touched,
1479 * pages will stay not present in virtual address space
1481 set_page_guard(zone
, &page
[size
], high
, migratetype
);
1484 list_add(&page
[size
].lru
, &area
->free_list
[migratetype
]);
1486 set_page_order(&page
[size
], high
);
1491 * This page is about to be returned from the page allocator
1493 static inline int check_new_page(struct page
*page
)
1495 const char *bad_reason
= NULL
;
1496 unsigned long bad_flags
= 0;
1498 if (unlikely(atomic_read(&page
->_mapcount
) != -1))
1499 bad_reason
= "nonzero mapcount";
1500 if (unlikely(page
->mapping
!= NULL
))
1501 bad_reason
= "non-NULL mapping";
1502 if (unlikely(page_ref_count(page
) != 0))
1503 bad_reason
= "nonzero _count";
1504 if (unlikely(page
->flags
& __PG_HWPOISON
)) {
1505 bad_reason
= "HWPoisoned (hardware-corrupted)";
1506 bad_flags
= __PG_HWPOISON
;
1508 if (unlikely(page
->flags
& PAGE_FLAGS_CHECK_AT_PREP
)) {
1509 bad_reason
= "PAGE_FLAGS_CHECK_AT_PREP flag set";
1510 bad_flags
= PAGE_FLAGS_CHECK_AT_PREP
;
1513 if (unlikely(page
->mem_cgroup
))
1514 bad_reason
= "page still charged to cgroup";
1516 if (unlikely(bad_reason
)) {
1517 bad_page(page
, bad_reason
, bad_flags
);
1523 static inline bool free_pages_prezeroed(bool poisoned
)
1525 return IS_ENABLED(CONFIG_PAGE_POISONING_ZERO
) &&
1526 page_poisoning_enabled() && poisoned
;
1529 static int prep_new_page(struct page
*page
, unsigned int order
, gfp_t gfp_flags
,
1530 unsigned int alloc_flags
)
1533 bool poisoned
= true;
1535 for (i
= 0; i
< (1 << order
); i
++) {
1536 struct page
*p
= page
+ i
;
1537 if (unlikely(check_new_page(p
)))
1540 poisoned
&= page_is_poisoned(p
);
1543 set_page_private(page
, 0);
1544 set_page_refcounted(page
);
1546 arch_alloc_page(page
, order
);
1547 kernel_map_pages(page
, 1 << order
, 1);
1548 kernel_poison_pages(page
, 1 << order
, 1);
1549 kasan_alloc_pages(page
, order
);
1551 if (!free_pages_prezeroed(poisoned
) && (gfp_flags
& __GFP_ZERO
))
1552 for (i
= 0; i
< (1 << order
); i
++)
1553 clear_highpage(page
+ i
);
1555 if (order
&& (gfp_flags
& __GFP_COMP
))
1556 prep_compound_page(page
, order
);
1558 set_page_owner(page
, order
, gfp_flags
);
1561 * page is set pfmemalloc when ALLOC_NO_WATERMARKS was necessary to
1562 * allocate the page. The expectation is that the caller is taking
1563 * steps that will free more memory. The caller should avoid the page
1564 * being used for !PFMEMALLOC purposes.
1566 if (alloc_flags
& ALLOC_NO_WATERMARKS
)
1567 set_page_pfmemalloc(page
);
1569 clear_page_pfmemalloc(page
);
1575 * Go through the free lists for the given migratetype and remove
1576 * the smallest available page from the freelists
1579 struct page
*__rmqueue_smallest(struct zone
*zone
, unsigned int order
,
1582 unsigned int current_order
;
1583 struct free_area
*area
;
1586 /* Find a page of the appropriate size in the preferred list */
1587 for (current_order
= order
; current_order
< MAX_ORDER
; ++current_order
) {
1588 area
= &(zone
->free_area
[current_order
]);
1589 page
= list_first_entry_or_null(&area
->free_list
[migratetype
],
1593 list_del(&page
->lru
);
1594 rmv_page_order(page
);
1596 expand(zone
, page
, order
, current_order
, area
, migratetype
);
1597 set_pcppage_migratetype(page
, migratetype
);
1606 * This array describes the order lists are fallen back to when
1607 * the free lists for the desirable migrate type are depleted
1609 static int fallbacks
[MIGRATE_TYPES
][4] = {
1610 [MIGRATE_UNMOVABLE
] = { MIGRATE_RECLAIMABLE
, MIGRATE_MOVABLE
, MIGRATE_TYPES
},
1611 [MIGRATE_RECLAIMABLE
] = { MIGRATE_UNMOVABLE
, MIGRATE_MOVABLE
, MIGRATE_TYPES
},
1612 [MIGRATE_MOVABLE
] = { MIGRATE_RECLAIMABLE
, MIGRATE_UNMOVABLE
, MIGRATE_TYPES
},
1614 [MIGRATE_CMA
] = { MIGRATE_TYPES
}, /* Never used */
1616 #ifdef CONFIG_MEMORY_ISOLATION
1617 [MIGRATE_ISOLATE
] = { MIGRATE_TYPES
}, /* Never used */
1622 static struct page
*__rmqueue_cma_fallback(struct zone
*zone
,
1625 return __rmqueue_smallest(zone
, order
, MIGRATE_CMA
);
1628 static inline struct page
*__rmqueue_cma_fallback(struct zone
*zone
,
1629 unsigned int order
) { return NULL
; }
1633 * Move the free pages in a range to the free lists of the requested type.
1634 * Note that start_page and end_pages are not aligned on a pageblock
1635 * boundary. If alignment is required, use move_freepages_block()
1637 int move_freepages(struct zone
*zone
,
1638 struct page
*start_page
, struct page
*end_page
,
1643 int pages_moved
= 0;
1645 #ifndef CONFIG_HOLES_IN_ZONE
1647 * page_zone is not safe to call in this context when
1648 * CONFIG_HOLES_IN_ZONE is set. This bug check is probably redundant
1649 * anyway as we check zone boundaries in move_freepages_block().
1650 * Remove at a later date when no bug reports exist related to
1651 * grouping pages by mobility
1653 VM_BUG_ON(page_zone(start_page
) != page_zone(end_page
));
1656 for (page
= start_page
; page
<= end_page
;) {
1657 /* Make sure we are not inadvertently changing nodes */
1658 VM_BUG_ON_PAGE(page_to_nid(page
) != zone_to_nid(zone
), page
);
1660 if (!pfn_valid_within(page_to_pfn(page
))) {
1665 if (!PageBuddy(page
)) {
1670 order
= page_order(page
);
1671 list_move(&page
->lru
,
1672 &zone
->free_area
[order
].free_list
[migratetype
]);
1674 pages_moved
+= 1 << order
;
1680 int move_freepages_block(struct zone
*zone
, struct page
*page
,
1683 unsigned long start_pfn
, end_pfn
;
1684 struct page
*start_page
, *end_page
;
1686 start_pfn
= page_to_pfn(page
);
1687 start_pfn
= start_pfn
& ~(pageblock_nr_pages
-1);
1688 start_page
= pfn_to_page(start_pfn
);
1689 end_page
= start_page
+ pageblock_nr_pages
- 1;
1690 end_pfn
= start_pfn
+ pageblock_nr_pages
- 1;
1692 /* Do not cross zone boundaries */
1693 if (!zone_spans_pfn(zone
, start_pfn
))
1695 if (!zone_spans_pfn(zone
, end_pfn
))
1698 return move_freepages(zone
, start_page
, end_page
, migratetype
);
1701 static void change_pageblock_range(struct page
*pageblock_page
,
1702 int start_order
, int migratetype
)
1704 int nr_pageblocks
= 1 << (start_order
- pageblock_order
);
1706 while (nr_pageblocks
--) {
1707 set_pageblock_migratetype(pageblock_page
, migratetype
);
1708 pageblock_page
+= pageblock_nr_pages
;
1713 * When we are falling back to another migratetype during allocation, try to
1714 * steal extra free pages from the same pageblocks to satisfy further
1715 * allocations, instead of polluting multiple pageblocks.
1717 * If we are stealing a relatively large buddy page, it is likely there will
1718 * be more free pages in the pageblock, so try to steal them all. For
1719 * reclaimable and unmovable allocations, we steal regardless of page size,
1720 * as fragmentation caused by those allocations polluting movable pageblocks
1721 * is worse than movable allocations stealing from unmovable and reclaimable
1724 static bool can_steal_fallback(unsigned int order
, int start_mt
)
1727 * Leaving this order check is intended, although there is
1728 * relaxed order check in next check. The reason is that
1729 * we can actually steal whole pageblock if this condition met,
1730 * but, below check doesn't guarantee it and that is just heuristic
1731 * so could be changed anytime.
1733 if (order
>= pageblock_order
)
1736 if (order
>= pageblock_order
/ 2 ||
1737 start_mt
== MIGRATE_RECLAIMABLE
||
1738 start_mt
== MIGRATE_UNMOVABLE
||
1739 page_group_by_mobility_disabled
)
1746 * This function implements actual steal behaviour. If order is large enough,
1747 * we can steal whole pageblock. If not, we first move freepages in this
1748 * pageblock and check whether half of pages are moved or not. If half of
1749 * pages are moved, we can change migratetype of pageblock and permanently
1750 * use it's pages as requested migratetype in the future.
1752 static void steal_suitable_fallback(struct zone
*zone
, struct page
*page
,
1755 unsigned int current_order
= page_order(page
);
1758 /* Take ownership for orders >= pageblock_order */
1759 if (current_order
>= pageblock_order
) {
1760 change_pageblock_range(page
, current_order
, start_type
);
1764 pages
= move_freepages_block(zone
, page
, start_type
);
1766 /* Claim the whole block if over half of it is free */
1767 if (pages
>= (1 << (pageblock_order
-1)) ||
1768 page_group_by_mobility_disabled
)
1769 set_pageblock_migratetype(page
, start_type
);
1773 * Check whether there is a suitable fallback freepage with requested order.
1774 * If only_stealable is true, this function returns fallback_mt only if
1775 * we can steal other freepages all together. This would help to reduce
1776 * fragmentation due to mixed migratetype pages in one pageblock.
1778 int find_suitable_fallback(struct free_area
*area
, unsigned int order
,
1779 int migratetype
, bool only_stealable
, bool *can_steal
)
1784 if (area
->nr_free
== 0)
1789 fallback_mt
= fallbacks
[migratetype
][i
];
1790 if (fallback_mt
== MIGRATE_TYPES
)
1793 if (list_empty(&area
->free_list
[fallback_mt
]))
1796 if (can_steal_fallback(order
, migratetype
))
1799 if (!only_stealable
)
1810 * Reserve a pageblock for exclusive use of high-order atomic allocations if
1811 * there are no empty page blocks that contain a page with a suitable order
1813 static void reserve_highatomic_pageblock(struct page
*page
, struct zone
*zone
,
1814 unsigned int alloc_order
)
1817 unsigned long max_managed
, flags
;
1820 * Limit the number reserved to 1 pageblock or roughly 1% of a zone.
1821 * Check is race-prone but harmless.
1823 max_managed
= (zone
->managed_pages
/ 100) + pageblock_nr_pages
;
1824 if (zone
->nr_reserved_highatomic
>= max_managed
)
1827 spin_lock_irqsave(&zone
->lock
, flags
);
1829 /* Recheck the nr_reserved_highatomic limit under the lock */
1830 if (zone
->nr_reserved_highatomic
>= max_managed
)
1834 mt
= get_pageblock_migratetype(page
);
1835 if (mt
!= MIGRATE_HIGHATOMIC
&&
1836 !is_migrate_isolate(mt
) && !is_migrate_cma(mt
)) {
1837 zone
->nr_reserved_highatomic
+= pageblock_nr_pages
;
1838 set_pageblock_migratetype(page
, MIGRATE_HIGHATOMIC
);
1839 move_freepages_block(zone
, page
, MIGRATE_HIGHATOMIC
);
1843 spin_unlock_irqrestore(&zone
->lock
, flags
);
1847 * Used when an allocation is about to fail under memory pressure. This
1848 * potentially hurts the reliability of high-order allocations when under
1849 * intense memory pressure but failed atomic allocations should be easier
1850 * to recover from than an OOM.
1852 static void unreserve_highatomic_pageblock(const struct alloc_context
*ac
)
1854 struct zonelist
*zonelist
= ac
->zonelist
;
1855 unsigned long flags
;
1861 for_each_zone_zonelist_nodemask(zone
, z
, zonelist
, ac
->high_zoneidx
,
1863 /* Preserve at least one pageblock */
1864 if (zone
->nr_reserved_highatomic
<= pageblock_nr_pages
)
1867 spin_lock_irqsave(&zone
->lock
, flags
);
1868 for (order
= 0; order
< MAX_ORDER
; order
++) {
1869 struct free_area
*area
= &(zone
->free_area
[order
]);
1871 page
= list_first_entry_or_null(
1872 &area
->free_list
[MIGRATE_HIGHATOMIC
],
1878 * It should never happen but changes to locking could
1879 * inadvertently allow a per-cpu drain to add pages
1880 * to MIGRATE_HIGHATOMIC while unreserving so be safe
1881 * and watch for underflows.
1883 zone
->nr_reserved_highatomic
-= min(pageblock_nr_pages
,
1884 zone
->nr_reserved_highatomic
);
1887 * Convert to ac->migratetype and avoid the normal
1888 * pageblock stealing heuristics. Minimally, the caller
1889 * is doing the work and needs the pages. More
1890 * importantly, if the block was always converted to
1891 * MIGRATE_UNMOVABLE or another type then the number
1892 * of pageblocks that cannot be completely freed
1895 set_pageblock_migratetype(page
, ac
->migratetype
);
1896 move_freepages_block(zone
, page
, ac
->migratetype
);
1897 spin_unlock_irqrestore(&zone
->lock
, flags
);
1900 spin_unlock_irqrestore(&zone
->lock
, flags
);
1904 /* Remove an element from the buddy allocator from the fallback list */
1905 static inline struct page
*
1906 __rmqueue_fallback(struct zone
*zone
, unsigned int order
, int start_migratetype
)
1908 struct free_area
*area
;
1909 unsigned int current_order
;
1914 /* Find the largest possible block of pages in the other list */
1915 for (current_order
= MAX_ORDER
-1;
1916 current_order
>= order
&& current_order
<= MAX_ORDER
-1;
1918 area
= &(zone
->free_area
[current_order
]);
1919 fallback_mt
= find_suitable_fallback(area
, current_order
,
1920 start_migratetype
, false, &can_steal
);
1921 if (fallback_mt
== -1)
1924 page
= list_first_entry(&area
->free_list
[fallback_mt
],
1927 steal_suitable_fallback(zone
, page
, start_migratetype
);
1929 /* Remove the page from the freelists */
1931 list_del(&page
->lru
);
1932 rmv_page_order(page
);
1934 expand(zone
, page
, order
, current_order
, area
,
1937 * The pcppage_migratetype may differ from pageblock's
1938 * migratetype depending on the decisions in
1939 * find_suitable_fallback(). This is OK as long as it does not
1940 * differ for MIGRATE_CMA pageblocks. Those can be used as
1941 * fallback only via special __rmqueue_cma_fallback() function
1943 set_pcppage_migratetype(page
, start_migratetype
);
1945 trace_mm_page_alloc_extfrag(page
, order
, current_order
,
1946 start_migratetype
, fallback_mt
);
1955 * Do the hard work of removing an element from the buddy allocator.
1956 * Call me with the zone->lock already held.
1958 static struct page
*__rmqueue(struct zone
*zone
, unsigned int order
,
1963 page
= __rmqueue_smallest(zone
, order
, migratetype
);
1964 if (unlikely(!page
)) {
1965 if (migratetype
== MIGRATE_MOVABLE
)
1966 page
= __rmqueue_cma_fallback(zone
, order
);
1969 page
= __rmqueue_fallback(zone
, order
, migratetype
);
1972 trace_mm_page_alloc_zone_locked(page
, order
, migratetype
);
1977 * Obtain a specified number of elements from the buddy allocator, all under
1978 * a single hold of the lock, for efficiency. Add them to the supplied list.
1979 * Returns the number of new pages which were placed at *list.
1981 static int rmqueue_bulk(struct zone
*zone
, unsigned int order
,
1982 unsigned long count
, struct list_head
*list
,
1983 int migratetype
, bool cold
)
1987 spin_lock(&zone
->lock
);
1988 for (i
= 0; i
< count
; ++i
) {
1989 struct page
*page
= __rmqueue(zone
, order
, migratetype
);
1990 if (unlikely(page
== NULL
))
1994 * Split buddy pages returned by expand() are received here
1995 * in physical page order. The page is added to the callers and
1996 * list and the list head then moves forward. From the callers
1997 * perspective, the linked list is ordered by page number in
1998 * some conditions. This is useful for IO devices that can
1999 * merge IO requests if the physical pages are ordered
2003 list_add(&page
->lru
, list
);
2005 list_add_tail(&page
->lru
, list
);
2007 if (is_migrate_cma(get_pcppage_migratetype(page
)))
2008 __mod_zone_page_state(zone
, NR_FREE_CMA_PAGES
,
2011 __mod_zone_page_state(zone
, NR_FREE_PAGES
, -(i
<< order
));
2012 spin_unlock(&zone
->lock
);
2018 * Called from the vmstat counter updater to drain pagesets of this
2019 * currently executing processor on remote nodes after they have
2022 * Note that this function must be called with the thread pinned to
2023 * a single processor.
2025 void drain_zone_pages(struct zone
*zone
, struct per_cpu_pages
*pcp
)
2027 unsigned long flags
;
2028 int to_drain
, batch
;
2030 local_irq_save(flags
);
2031 batch
= READ_ONCE(pcp
->batch
);
2032 to_drain
= min(pcp
->count
, batch
);
2034 free_pcppages_bulk(zone
, to_drain
, pcp
);
2035 pcp
->count
-= to_drain
;
2037 local_irq_restore(flags
);
2042 * Drain pcplists of the indicated processor and zone.
2044 * The processor must either be the current processor and the
2045 * thread pinned to the current processor or a processor that
2048 static void drain_pages_zone(unsigned int cpu
, struct zone
*zone
)
2050 unsigned long flags
;
2051 struct per_cpu_pageset
*pset
;
2052 struct per_cpu_pages
*pcp
;
2054 local_irq_save(flags
);
2055 pset
= per_cpu_ptr(zone
->pageset
, cpu
);
2059 free_pcppages_bulk(zone
, pcp
->count
, pcp
);
2062 local_irq_restore(flags
);
2066 * Drain pcplists of all zones on the indicated processor.
2068 * The processor must either be the current processor and the
2069 * thread pinned to the current processor or a processor that
2072 static void drain_pages(unsigned int cpu
)
2076 for_each_populated_zone(zone
) {
2077 drain_pages_zone(cpu
, zone
);
2082 * Spill all of this CPU's per-cpu pages back into the buddy allocator.
2084 * The CPU has to be pinned. When zone parameter is non-NULL, spill just
2085 * the single zone's pages.
2087 void drain_local_pages(struct zone
*zone
)
2089 int cpu
= smp_processor_id();
2092 drain_pages_zone(cpu
, zone
);
2098 * Spill all the per-cpu pages from all CPUs back into the buddy allocator.
2100 * When zone parameter is non-NULL, spill just the single zone's pages.
2102 * Note that this code is protected against sending an IPI to an offline
2103 * CPU but does not guarantee sending an IPI to newly hotplugged CPUs:
2104 * on_each_cpu_mask() blocks hotplug and won't talk to offlined CPUs but
2105 * nothing keeps CPUs from showing up after we populated the cpumask and
2106 * before the call to on_each_cpu_mask().
2108 void drain_all_pages(struct zone
*zone
)
2113 * Allocate in the BSS so we wont require allocation in
2114 * direct reclaim path for CONFIG_CPUMASK_OFFSTACK=y
2116 static cpumask_t cpus_with_pcps
;
2119 * We don't care about racing with CPU hotplug event
2120 * as offline notification will cause the notified
2121 * cpu to drain that CPU pcps and on_each_cpu_mask
2122 * disables preemption as part of its processing
2124 for_each_online_cpu(cpu
) {
2125 struct per_cpu_pageset
*pcp
;
2127 bool has_pcps
= false;
2130 pcp
= per_cpu_ptr(zone
->pageset
, cpu
);
2134 for_each_populated_zone(z
) {
2135 pcp
= per_cpu_ptr(z
->pageset
, cpu
);
2136 if (pcp
->pcp
.count
) {
2144 cpumask_set_cpu(cpu
, &cpus_with_pcps
);
2146 cpumask_clear_cpu(cpu
, &cpus_with_pcps
);
2148 on_each_cpu_mask(&cpus_with_pcps
, (smp_call_func_t
) drain_local_pages
,
2152 #ifdef CONFIG_HIBERNATION
2154 void mark_free_pages(struct zone
*zone
)
2156 unsigned long pfn
, max_zone_pfn
;
2157 unsigned long flags
;
2158 unsigned int order
, t
;
2161 if (zone_is_empty(zone
))
2164 spin_lock_irqsave(&zone
->lock
, flags
);
2166 max_zone_pfn
= zone_end_pfn(zone
);
2167 for (pfn
= zone
->zone_start_pfn
; pfn
< max_zone_pfn
; pfn
++)
2168 if (pfn_valid(pfn
)) {
2169 page
= pfn_to_page(pfn
);
2171 if (page_zone(page
) != zone
)
2174 if (!swsusp_page_is_forbidden(page
))
2175 swsusp_unset_page_free(page
);
2178 for_each_migratetype_order(order
, t
) {
2179 list_for_each_entry(page
,
2180 &zone
->free_area
[order
].free_list
[t
], lru
) {
2183 pfn
= page_to_pfn(page
);
2184 for (i
= 0; i
< (1UL << order
); i
++)
2185 swsusp_set_page_free(pfn_to_page(pfn
+ i
));
2188 spin_unlock_irqrestore(&zone
->lock
, flags
);
2190 #endif /* CONFIG_PM */
2193 * Free a 0-order page
2194 * cold == true ? free a cold page : free a hot page
2196 void free_hot_cold_page(struct page
*page
, bool cold
)
2198 struct zone
*zone
= page_zone(page
);
2199 struct per_cpu_pages
*pcp
;
2200 unsigned long flags
;
2201 unsigned long pfn
= page_to_pfn(page
);
2204 if (!free_pages_prepare(page
, 0))
2207 migratetype
= get_pfnblock_migratetype(page
, pfn
);
2208 set_pcppage_migratetype(page
, migratetype
);
2209 local_irq_save(flags
);
2210 __count_vm_event(PGFREE
);
2213 * We only track unmovable, reclaimable and movable on pcp lists.
2214 * Free ISOLATE pages back to the allocator because they are being
2215 * offlined but treat RESERVE as movable pages so we can get those
2216 * areas back if necessary. Otherwise, we may have to free
2217 * excessively into the page allocator
2219 if (migratetype
>= MIGRATE_PCPTYPES
) {
2220 if (unlikely(is_migrate_isolate(migratetype
))) {
2221 free_one_page(zone
, page
, pfn
, 0, migratetype
);
2224 migratetype
= MIGRATE_MOVABLE
;
2227 pcp
= &this_cpu_ptr(zone
->pageset
)->pcp
;
2229 list_add(&page
->lru
, &pcp
->lists
[migratetype
]);
2231 list_add_tail(&page
->lru
, &pcp
->lists
[migratetype
]);
2233 if (pcp
->count
>= pcp
->high
) {
2234 unsigned long batch
= READ_ONCE(pcp
->batch
);
2235 free_pcppages_bulk(zone
, batch
, pcp
);
2236 pcp
->count
-= batch
;
2240 local_irq_restore(flags
);
2244 * Free a list of 0-order pages
2246 void free_hot_cold_page_list(struct list_head
*list
, bool cold
)
2248 struct page
*page
, *next
;
2250 list_for_each_entry_safe(page
, next
, list
, lru
) {
2251 trace_mm_page_free_batched(page
, cold
);
2252 free_hot_cold_page(page
, cold
);
2257 * split_page takes a non-compound higher-order page, and splits it into
2258 * n (1<<order) sub-pages: page[0..n]
2259 * Each sub-page must be freed individually.
2261 * Note: this is probably too low level an operation for use in drivers.
2262 * Please consult with lkml before using this in your driver.
2264 void split_page(struct page
*page
, unsigned int order
)
2269 VM_BUG_ON_PAGE(PageCompound(page
), page
);
2270 VM_BUG_ON_PAGE(!page_count(page
), page
);
2272 #ifdef CONFIG_KMEMCHECK
2274 * Split shadow pages too, because free(page[0]) would
2275 * otherwise free the whole shadow.
2277 if (kmemcheck_page_is_tracked(page
))
2278 split_page(virt_to_page(page
[0].shadow
), order
);
2281 gfp_mask
= get_page_owner_gfp(page
);
2282 set_page_owner(page
, 0, gfp_mask
);
2283 for (i
= 1; i
< (1 << order
); i
++) {
2284 set_page_refcounted(page
+ i
);
2285 set_page_owner(page
+ i
, 0, gfp_mask
);
2288 EXPORT_SYMBOL_GPL(split_page
);
2290 int __isolate_free_page(struct page
*page
, unsigned int order
)
2292 unsigned long watermark
;
2296 BUG_ON(!PageBuddy(page
));
2298 zone
= page_zone(page
);
2299 mt
= get_pageblock_migratetype(page
);
2301 if (!is_migrate_isolate(mt
)) {
2302 /* Obey watermarks as if the page was being allocated */
2303 watermark
= low_wmark_pages(zone
) + (1 << order
);
2304 if (!zone_watermark_ok(zone
, 0, watermark
, 0, 0))
2307 __mod_zone_freepage_state(zone
, -(1UL << order
), mt
);
2310 /* Remove page from free list */
2311 list_del(&page
->lru
);
2312 zone
->free_area
[order
].nr_free
--;
2313 rmv_page_order(page
);
2315 set_page_owner(page
, order
, __GFP_MOVABLE
);
2317 /* Set the pageblock if the isolated page is at least a pageblock */
2318 if (order
>= pageblock_order
- 1) {
2319 struct page
*endpage
= page
+ (1 << order
) - 1;
2320 for (; page
< endpage
; page
+= pageblock_nr_pages
) {
2321 int mt
= get_pageblock_migratetype(page
);
2322 if (!is_migrate_isolate(mt
) && !is_migrate_cma(mt
))
2323 set_pageblock_migratetype(page
,
2329 return 1UL << order
;
2333 * Similar to split_page except the page is already free. As this is only
2334 * being used for migration, the migratetype of the block also changes.
2335 * As this is called with interrupts disabled, the caller is responsible
2336 * for calling arch_alloc_page() and kernel_map_page() after interrupts
2339 * Note: this is probably too low level an operation for use in drivers.
2340 * Please consult with lkml before using this in your driver.
2342 int split_free_page(struct page
*page
)
2347 order
= page_order(page
);
2349 nr_pages
= __isolate_free_page(page
, order
);
2353 /* Split into individual pages */
2354 set_page_refcounted(page
);
2355 split_page(page
, order
);
2360 * Update NUMA hit/miss statistics
2362 * Must be called with interrupts disabled.
2364 * When __GFP_OTHER_NODE is set assume the node of the preferred
2365 * zone is the local node. This is useful for daemons who allocate
2366 * memory on behalf of other processes.
2368 static inline void zone_statistics(struct zone
*preferred_zone
, struct zone
*z
,
2372 int local_nid
= numa_node_id();
2373 enum zone_stat_item local_stat
= NUMA_LOCAL
;
2375 if (unlikely(flags
& __GFP_OTHER_NODE
)) {
2376 local_stat
= NUMA_OTHER
;
2377 local_nid
= preferred_zone
->node
;
2380 if (z
->node
== local_nid
) {
2381 __inc_zone_state(z
, NUMA_HIT
);
2382 __inc_zone_state(z
, local_stat
);
2384 __inc_zone_state(z
, NUMA_MISS
);
2385 __inc_zone_state(preferred_zone
, NUMA_FOREIGN
);
2391 * Allocate a page from the given zone. Use pcplists for order-0 allocations.
2394 struct page
*buffered_rmqueue(struct zone
*preferred_zone
,
2395 struct zone
*zone
, unsigned int order
,
2396 gfp_t gfp_flags
, unsigned int alloc_flags
,
2399 unsigned long flags
;
2401 bool cold
= ((gfp_flags
& __GFP_COLD
) != 0);
2403 if (likely(order
== 0)) {
2404 struct per_cpu_pages
*pcp
;
2405 struct list_head
*list
;
2407 local_irq_save(flags
);
2408 pcp
= &this_cpu_ptr(zone
->pageset
)->pcp
;
2409 list
= &pcp
->lists
[migratetype
];
2410 if (list_empty(list
)) {
2411 pcp
->count
+= rmqueue_bulk(zone
, 0,
2414 if (unlikely(list_empty(list
)))
2419 page
= list_last_entry(list
, struct page
, lru
);
2421 page
= list_first_entry(list
, struct page
, lru
);
2423 __dec_zone_state(zone
, NR_ALLOC_BATCH
);
2424 list_del(&page
->lru
);
2428 * We most definitely don't want callers attempting to
2429 * allocate greater than order-1 page units with __GFP_NOFAIL.
2431 WARN_ON_ONCE((gfp_flags
& __GFP_NOFAIL
) && (order
> 1));
2432 spin_lock_irqsave(&zone
->lock
, flags
);
2435 if (alloc_flags
& ALLOC_HARDER
) {
2436 page
= __rmqueue_smallest(zone
, order
, MIGRATE_HIGHATOMIC
);
2438 trace_mm_page_alloc_zone_locked(page
, order
, migratetype
);
2441 page
= __rmqueue(zone
, order
, migratetype
);
2442 spin_unlock(&zone
->lock
);
2445 __mod_zone_page_state(zone
, NR_ALLOC_BATCH
, -(1 << order
));
2446 __mod_zone_freepage_state(zone
, -(1 << order
),
2447 get_pcppage_migratetype(page
));
2450 if (atomic_long_read(&zone
->vm_stat
[NR_ALLOC_BATCH
]) <= 0 &&
2451 !test_bit(ZONE_FAIR_DEPLETED
, &zone
->flags
))
2452 set_bit(ZONE_FAIR_DEPLETED
, &zone
->flags
);
2454 __count_zone_vm_events(PGALLOC
, zone
, 1 << order
);
2455 zone_statistics(preferred_zone
, zone
, gfp_flags
);
2456 local_irq_restore(flags
);
2458 VM_BUG_ON_PAGE(bad_range(zone
, page
), page
);
2462 local_irq_restore(flags
);
2466 #ifdef CONFIG_FAIL_PAGE_ALLOC
2469 struct fault_attr attr
;
2471 bool ignore_gfp_highmem
;
2472 bool ignore_gfp_reclaim
;
2474 } fail_page_alloc
= {
2475 .attr
= FAULT_ATTR_INITIALIZER
,
2476 .ignore_gfp_reclaim
= true,
2477 .ignore_gfp_highmem
= true,
2481 static int __init
setup_fail_page_alloc(char *str
)
2483 return setup_fault_attr(&fail_page_alloc
.attr
, str
);
2485 __setup("fail_page_alloc=", setup_fail_page_alloc
);
2487 static bool should_fail_alloc_page(gfp_t gfp_mask
, unsigned int order
)
2489 if (order
< fail_page_alloc
.min_order
)
2491 if (gfp_mask
& __GFP_NOFAIL
)
2493 if (fail_page_alloc
.ignore_gfp_highmem
&& (gfp_mask
& __GFP_HIGHMEM
))
2495 if (fail_page_alloc
.ignore_gfp_reclaim
&&
2496 (gfp_mask
& __GFP_DIRECT_RECLAIM
))
2499 return should_fail(&fail_page_alloc
.attr
, 1 << order
);
2502 #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
2504 static int __init
fail_page_alloc_debugfs(void)
2506 umode_t mode
= S_IFREG
| S_IRUSR
| S_IWUSR
;
2509 dir
= fault_create_debugfs_attr("fail_page_alloc", NULL
,
2510 &fail_page_alloc
.attr
);
2512 return PTR_ERR(dir
);
2514 if (!debugfs_create_bool("ignore-gfp-wait", mode
, dir
,
2515 &fail_page_alloc
.ignore_gfp_reclaim
))
2517 if (!debugfs_create_bool("ignore-gfp-highmem", mode
, dir
,
2518 &fail_page_alloc
.ignore_gfp_highmem
))
2520 if (!debugfs_create_u32("min-order", mode
, dir
,
2521 &fail_page_alloc
.min_order
))
2526 debugfs_remove_recursive(dir
);
2531 late_initcall(fail_page_alloc_debugfs
);
2533 #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
2535 #else /* CONFIG_FAIL_PAGE_ALLOC */
2537 static inline bool should_fail_alloc_page(gfp_t gfp_mask
, unsigned int order
)
2542 #endif /* CONFIG_FAIL_PAGE_ALLOC */
2545 * Return true if free base pages are above 'mark'. For high-order checks it
2546 * will return true of the order-0 watermark is reached and there is at least
2547 * one free page of a suitable size. Checking now avoids taking the zone lock
2548 * to check in the allocation paths if no pages are free.
2550 static bool __zone_watermark_ok(struct zone
*z
, unsigned int order
,
2551 unsigned long mark
, int classzone_idx
,
2552 unsigned int alloc_flags
,
2557 const bool alloc_harder
= (alloc_flags
& ALLOC_HARDER
);
2559 /* free_pages may go negative - that's OK */
2560 free_pages
-= (1 << order
) - 1;
2562 if (alloc_flags
& ALLOC_HIGH
)
2566 * If the caller does not have rights to ALLOC_HARDER then subtract
2567 * the high-atomic reserves. This will over-estimate the size of the
2568 * atomic reserve but it avoids a search.
2570 if (likely(!alloc_harder
))
2571 free_pages
-= z
->nr_reserved_highatomic
;
2576 /* If allocation can't use CMA areas don't use free CMA pages */
2577 if (!(alloc_flags
& ALLOC_CMA
))
2578 free_pages
-= zone_page_state(z
, NR_FREE_CMA_PAGES
);
2582 * Check watermarks for an order-0 allocation request. If these
2583 * are not met, then a high-order request also cannot go ahead
2584 * even if a suitable page happened to be free.
2586 if (free_pages
<= min
+ z
->lowmem_reserve
[classzone_idx
])
2589 /* If this is an order-0 request then the watermark is fine */
2593 /* For a high-order request, check at least one suitable page is free */
2594 for (o
= order
; o
< MAX_ORDER
; o
++) {
2595 struct free_area
*area
= &z
->free_area
[o
];
2604 for (mt
= 0; mt
< MIGRATE_PCPTYPES
; mt
++) {
2605 if (!list_empty(&area
->free_list
[mt
]))
2610 if ((alloc_flags
& ALLOC_CMA
) &&
2611 !list_empty(&area
->free_list
[MIGRATE_CMA
])) {
2619 bool zone_watermark_ok(struct zone
*z
, unsigned int order
, unsigned long mark
,
2620 int classzone_idx
, unsigned int alloc_flags
)
2622 return __zone_watermark_ok(z
, order
, mark
, classzone_idx
, alloc_flags
,
2623 zone_page_state(z
, NR_FREE_PAGES
));
2626 static inline bool zone_watermark_fast(struct zone
*z
, unsigned int order
,
2627 unsigned long mark
, int classzone_idx
, unsigned int alloc_flags
)
2629 long free_pages
= zone_page_state(z
, NR_FREE_PAGES
);
2633 /* If allocation can't use CMA areas don't use free CMA pages */
2634 if (!(alloc_flags
& ALLOC_CMA
))
2635 cma_pages
= zone_page_state(z
, NR_FREE_CMA_PAGES
);
2639 * Fast check for order-0 only. If this fails then the reserves
2640 * need to be calculated. There is a corner case where the check
2641 * passes but only the high-order atomic reserve are free. If
2642 * the caller is !atomic then it'll uselessly search the free
2643 * list. That corner case is then slower but it is harmless.
2645 if (!order
&& (free_pages
- cma_pages
) > mark
+ z
->lowmem_reserve
[classzone_idx
])
2648 return __zone_watermark_ok(z
, order
, mark
, classzone_idx
, alloc_flags
,
2652 bool zone_watermark_ok_safe(struct zone
*z
, unsigned int order
,
2653 unsigned long mark
, int classzone_idx
)
2655 long free_pages
= zone_page_state(z
, NR_FREE_PAGES
);
2657 if (z
->percpu_drift_mark
&& free_pages
< z
->percpu_drift_mark
)
2658 free_pages
= zone_page_state_snapshot(z
, NR_FREE_PAGES
);
2660 return __zone_watermark_ok(z
, order
, mark
, classzone_idx
, 0,
2665 static bool zone_local(struct zone
*local_zone
, struct zone
*zone
)
2667 return local_zone
->node
== zone
->node
;
2670 static bool zone_allows_reclaim(struct zone
*local_zone
, struct zone
*zone
)
2672 return node_distance(zone_to_nid(local_zone
), zone_to_nid(zone
)) <
2675 #else /* CONFIG_NUMA */
2676 static bool zone_local(struct zone
*local_zone
, struct zone
*zone
)
2681 static bool zone_allows_reclaim(struct zone
*local_zone
, struct zone
*zone
)
2685 #endif /* CONFIG_NUMA */
2687 static void reset_alloc_batches(struct zone
*preferred_zone
)
2689 struct zone
*zone
= preferred_zone
->zone_pgdat
->node_zones
;
2692 mod_zone_page_state(zone
, NR_ALLOC_BATCH
,
2693 high_wmark_pages(zone
) - low_wmark_pages(zone
) -
2694 atomic_long_read(&zone
->vm_stat
[NR_ALLOC_BATCH
]));
2695 clear_bit(ZONE_FAIR_DEPLETED
, &zone
->flags
);
2696 } while (zone
++ != preferred_zone
);
2700 * get_page_from_freelist goes through the zonelist trying to allocate
2703 static struct page
*
2704 get_page_from_freelist(gfp_t gfp_mask
, unsigned int order
, int alloc_flags
,
2705 const struct alloc_context
*ac
)
2707 struct zoneref
*z
= ac
->preferred_zoneref
;
2709 bool fair_skipped
= false;
2710 bool apply_fair
= (alloc_flags
& ALLOC_FAIR
);
2714 * Scan zonelist, looking for a zone with enough free.
2715 * See also __cpuset_node_allowed() comment in kernel/cpuset.c.
2717 for_next_zone_zonelist_nodemask(zone
, z
, ac
->zonelist
, ac
->high_zoneidx
,
2722 if (cpusets_enabled() &&
2723 (alloc_flags
& ALLOC_CPUSET
) &&
2724 !cpuset_zone_allowed(zone
, gfp_mask
))
2727 * Distribute pages in proportion to the individual
2728 * zone size to ensure fair page aging. The zone a
2729 * page was allocated in should have no effect on the
2730 * time the page has in memory before being reclaimed.
2733 if (test_bit(ZONE_FAIR_DEPLETED
, &zone
->flags
)) {
2734 fair_skipped
= true;
2737 if (!zone_local(ac
->preferred_zoneref
->zone
, zone
)) {
2744 * When allocating a page cache page for writing, we
2745 * want to get it from a zone that is within its dirty
2746 * limit, such that no single zone holds more than its
2747 * proportional share of globally allowed dirty pages.
2748 * The dirty limits take into account the zone's
2749 * lowmem reserves and high watermark so that kswapd
2750 * should be able to balance it without having to
2751 * write pages from its LRU list.
2753 * This may look like it could increase pressure on
2754 * lower zones by failing allocations in higher zones
2755 * before they are full. But the pages that do spill
2756 * over are limited as the lower zones are protected
2757 * by this very same mechanism. It should not become
2758 * a practical burden to them.
2760 * XXX: For now, allow allocations to potentially
2761 * exceed the per-zone dirty limit in the slowpath
2762 * (spread_dirty_pages unset) before going into reclaim,
2763 * which is important when on a NUMA setup the allowed
2764 * zones are together not big enough to reach the
2765 * global limit. The proper fix for these situations
2766 * will require awareness of zones in the
2767 * dirty-throttling and the flusher threads.
2769 if (ac
->spread_dirty_pages
&& !zone_dirty_ok(zone
))
2772 mark
= zone
->watermark
[alloc_flags
& ALLOC_WMARK_MASK
];
2773 if (!zone_watermark_fast(zone
, order
, mark
,
2774 ac_classzone_idx(ac
), alloc_flags
)) {
2777 /* Checked here to keep the fast path fast */
2778 BUILD_BUG_ON(ALLOC_NO_WATERMARKS
< NR_WMARK
);
2779 if (alloc_flags
& ALLOC_NO_WATERMARKS
)
2782 if (zone_reclaim_mode
== 0 ||
2783 !zone_allows_reclaim(ac
->preferred_zoneref
->zone
, zone
))
2786 ret
= zone_reclaim(zone
, gfp_mask
, order
);
2788 case ZONE_RECLAIM_NOSCAN
:
2791 case ZONE_RECLAIM_FULL
:
2792 /* scanned but unreclaimable */
2795 /* did we reclaim enough */
2796 if (zone_watermark_ok(zone
, order
, mark
,
2797 ac_classzone_idx(ac
), alloc_flags
))
2805 page
= buffered_rmqueue(ac
->preferred_zoneref
->zone
, zone
, order
,
2806 gfp_mask
, alloc_flags
, ac
->migratetype
);
2808 if (prep_new_page(page
, order
, gfp_mask
, alloc_flags
))
2812 * If this is a high-order atomic allocation then check
2813 * if the pageblock should be reserved for the future
2815 if (unlikely(order
&& (alloc_flags
& ALLOC_HARDER
)))
2816 reserve_highatomic_pageblock(page
, zone
, order
);
2823 * The first pass makes sure allocations are spread fairly within the
2824 * local node. However, the local node might have free pages left
2825 * after the fairness batches are exhausted, and remote zones haven't
2826 * even been considered yet. Try once more without fairness, and
2827 * include remote zones now, before entering the slowpath and waking
2828 * kswapd: prefer spilling to a remote zone over swapping locally.
2833 fair_skipped
= false;
2834 reset_alloc_batches(ac
->preferred_zoneref
->zone
);
2842 * Large machines with many possible nodes should not always dump per-node
2843 * meminfo in irq context.
2845 static inline bool should_suppress_show_mem(void)
2850 ret
= in_interrupt();
2855 static DEFINE_RATELIMIT_STATE(nopage_rs
,
2856 DEFAULT_RATELIMIT_INTERVAL
,
2857 DEFAULT_RATELIMIT_BURST
);
2859 void warn_alloc_failed(gfp_t gfp_mask
, unsigned int order
, const char *fmt
, ...)
2861 unsigned int filter
= SHOW_MEM_FILTER_NODES
;
2863 if ((gfp_mask
& __GFP_NOWARN
) || !__ratelimit(&nopage_rs
) ||
2864 debug_guardpage_minorder() > 0)
2868 * This documents exceptions given to allocations in certain
2869 * contexts that are allowed to allocate outside current's set
2872 if (!(gfp_mask
& __GFP_NOMEMALLOC
))
2873 if (test_thread_flag(TIF_MEMDIE
) ||
2874 (current
->flags
& (PF_MEMALLOC
| PF_EXITING
)))
2875 filter
&= ~SHOW_MEM_FILTER_NODES
;
2876 if (in_interrupt() || !(gfp_mask
& __GFP_DIRECT_RECLAIM
))
2877 filter
&= ~SHOW_MEM_FILTER_NODES
;
2880 struct va_format vaf
;
2883 va_start(args
, fmt
);
2888 pr_warn("%pV", &vaf
);
2893 pr_warn("%s: page allocation failure: order:%u, mode:%#x(%pGg)\n",
2894 current
->comm
, order
, gfp_mask
, &gfp_mask
);
2896 if (!should_suppress_show_mem())
2900 static inline struct page
*
2901 __alloc_pages_may_oom(gfp_t gfp_mask
, unsigned int order
,
2902 const struct alloc_context
*ac
, unsigned long *did_some_progress
)
2904 struct oom_control oc
= {
2905 .zonelist
= ac
->zonelist
,
2906 .nodemask
= ac
->nodemask
,
2907 .gfp_mask
= gfp_mask
,
2912 *did_some_progress
= 0;
2915 * Acquire the oom lock. If that fails, somebody else is
2916 * making progress for us.
2918 if (!mutex_trylock(&oom_lock
)) {
2919 *did_some_progress
= 1;
2920 schedule_timeout_uninterruptible(1);
2925 * Go through the zonelist yet one more time, keep very high watermark
2926 * here, this is only to catch a parallel oom killing, we must fail if
2927 * we're still under heavy pressure.
2929 page
= get_page_from_freelist(gfp_mask
| __GFP_HARDWALL
, order
,
2930 ALLOC_WMARK_HIGH
|ALLOC_CPUSET
, ac
);
2934 if (!(gfp_mask
& __GFP_NOFAIL
)) {
2935 /* Coredumps can quickly deplete all memory reserves */
2936 if (current
->flags
& PF_DUMPCORE
)
2938 /* The OOM killer will not help higher order allocs */
2939 if (order
> PAGE_ALLOC_COSTLY_ORDER
)
2941 /* The OOM killer does not needlessly kill tasks for lowmem */
2942 if (ac
->high_zoneidx
< ZONE_NORMAL
)
2944 if (pm_suspended_storage())
2947 * XXX: GFP_NOFS allocations should rather fail than rely on
2948 * other request to make a forward progress.
2949 * We are in an unfortunate situation where out_of_memory cannot
2950 * do much for this context but let's try it to at least get
2951 * access to memory reserved if the current task is killed (see
2952 * out_of_memory). Once filesystems are ready to handle allocation
2953 * failures more gracefully we should just bail out here.
2956 /* The OOM killer may not free memory on a specific node */
2957 if (gfp_mask
& __GFP_THISNODE
)
2960 /* Exhausted what can be done so it's blamo time */
2961 if (out_of_memory(&oc
) || WARN_ON_ONCE(gfp_mask
& __GFP_NOFAIL
)) {
2962 *did_some_progress
= 1;
2964 if (gfp_mask
& __GFP_NOFAIL
) {
2965 page
= get_page_from_freelist(gfp_mask
, order
,
2966 ALLOC_NO_WATERMARKS
|ALLOC_CPUSET
, ac
);
2968 * fallback to ignore cpuset restriction if our nodes
2972 page
= get_page_from_freelist(gfp_mask
, order
,
2973 ALLOC_NO_WATERMARKS
, ac
);
2977 mutex_unlock(&oom_lock
);
2981 #ifdef CONFIG_COMPACTION
2982 /* Try memory compaction for high-order allocations before reclaim */
2983 static struct page
*
2984 __alloc_pages_direct_compact(gfp_t gfp_mask
, unsigned int order
,
2985 unsigned int alloc_flags
, const struct alloc_context
*ac
,
2986 enum migrate_mode mode
, int *contended_compaction
,
2987 bool *deferred_compaction
)
2989 unsigned long compact_result
;
2995 current
->flags
|= PF_MEMALLOC
;
2996 compact_result
= try_to_compact_pages(gfp_mask
, order
, alloc_flags
, ac
,
2997 mode
, contended_compaction
);
2998 current
->flags
&= ~PF_MEMALLOC
;
3000 switch (compact_result
) {
3001 case COMPACT_DEFERRED
:
3002 *deferred_compaction
= true;
3004 case COMPACT_SKIPPED
:
3011 * At least in one zone compaction wasn't deferred or skipped, so let's
3012 * count a compaction stall
3014 count_vm_event(COMPACTSTALL
);
3016 page
= get_page_from_freelist(gfp_mask
, order
,
3017 alloc_flags
& ~ALLOC_NO_WATERMARKS
, ac
);
3020 struct zone
*zone
= page_zone(page
);
3022 zone
->compact_blockskip_flush
= false;
3023 compaction_defer_reset(zone
, order
, true);
3024 count_vm_event(COMPACTSUCCESS
);
3029 * It's bad if compaction run occurs and fails. The most likely reason
3030 * is that pages exist, but not enough to satisfy watermarks.
3032 count_vm_event(COMPACTFAIL
);
3039 static inline struct page
*
3040 __alloc_pages_direct_compact(gfp_t gfp_mask
, unsigned int order
,
3041 unsigned int alloc_flags
, const struct alloc_context
*ac
,
3042 enum migrate_mode mode
, int *contended_compaction
,
3043 bool *deferred_compaction
)
3047 #endif /* CONFIG_COMPACTION */
3049 /* Perform direct synchronous page reclaim */
3051 __perform_reclaim(gfp_t gfp_mask
, unsigned int order
,
3052 const struct alloc_context
*ac
)
3054 struct reclaim_state reclaim_state
;
3059 /* We now go into synchronous reclaim */
3060 cpuset_memory_pressure_bump();
3061 current
->flags
|= PF_MEMALLOC
;
3062 lockdep_set_current_reclaim_state(gfp_mask
);
3063 reclaim_state
.reclaimed_slab
= 0;
3064 current
->reclaim_state
= &reclaim_state
;
3066 progress
= try_to_free_pages(ac
->zonelist
, order
, gfp_mask
,
3069 current
->reclaim_state
= NULL
;
3070 lockdep_clear_current_reclaim_state();
3071 current
->flags
&= ~PF_MEMALLOC
;
3078 /* The really slow allocator path where we enter direct reclaim */
3079 static inline struct page
*
3080 __alloc_pages_direct_reclaim(gfp_t gfp_mask
, unsigned int order
,
3081 unsigned int alloc_flags
, const struct alloc_context
*ac
,
3082 unsigned long *did_some_progress
)
3084 struct page
*page
= NULL
;
3085 bool drained
= false;
3087 *did_some_progress
= __perform_reclaim(gfp_mask
, order
, ac
);
3088 if (unlikely(!(*did_some_progress
)))
3092 page
= get_page_from_freelist(gfp_mask
, order
,
3093 alloc_flags
& ~ALLOC_NO_WATERMARKS
, ac
);
3096 * If an allocation failed after direct reclaim, it could be because
3097 * pages are pinned on the per-cpu lists or in high alloc reserves.
3098 * Shrink them them and try again
3100 if (!page
&& !drained
) {
3101 unreserve_highatomic_pageblock(ac
);
3102 drain_all_pages(NULL
);
3110 static void wake_all_kswapds(unsigned int order
, const struct alloc_context
*ac
)
3115 for_each_zone_zonelist_nodemask(zone
, z
, ac
->zonelist
,
3116 ac
->high_zoneidx
, ac
->nodemask
)
3117 wakeup_kswapd(zone
, order
, ac_classzone_idx(ac
));
3120 static inline unsigned int
3121 gfp_to_alloc_flags(gfp_t gfp_mask
)
3123 unsigned int alloc_flags
= ALLOC_WMARK_MIN
| ALLOC_CPUSET
;
3125 /* __GFP_HIGH is assumed to be the same as ALLOC_HIGH to save a branch. */
3126 BUILD_BUG_ON(__GFP_HIGH
!= (__force gfp_t
) ALLOC_HIGH
);
3129 * The caller may dip into page reserves a bit more if the caller
3130 * cannot run direct reclaim, or if the caller has realtime scheduling
3131 * policy or is asking for __GFP_HIGH memory. GFP_ATOMIC requests will
3132 * set both ALLOC_HARDER (__GFP_ATOMIC) and ALLOC_HIGH (__GFP_HIGH).
3134 alloc_flags
|= (__force
int) (gfp_mask
& __GFP_HIGH
);
3136 if (gfp_mask
& __GFP_ATOMIC
) {
3138 * Not worth trying to allocate harder for __GFP_NOMEMALLOC even
3139 * if it can't schedule.
3141 if (!(gfp_mask
& __GFP_NOMEMALLOC
))
3142 alloc_flags
|= ALLOC_HARDER
;
3144 * Ignore cpuset mems for GFP_ATOMIC rather than fail, see the
3145 * comment for __cpuset_node_allowed().
3147 alloc_flags
&= ~ALLOC_CPUSET
;
3148 } else if (unlikely(rt_task(current
)) && !in_interrupt())
3149 alloc_flags
|= ALLOC_HARDER
;
3151 if (likely(!(gfp_mask
& __GFP_NOMEMALLOC
))) {
3152 if (gfp_mask
& __GFP_MEMALLOC
)
3153 alloc_flags
|= ALLOC_NO_WATERMARKS
;
3154 else if (in_serving_softirq() && (current
->flags
& PF_MEMALLOC
))
3155 alloc_flags
|= ALLOC_NO_WATERMARKS
;
3156 else if (!in_interrupt() &&
3157 ((current
->flags
& PF_MEMALLOC
) ||
3158 unlikely(test_thread_flag(TIF_MEMDIE
))))
3159 alloc_flags
|= ALLOC_NO_WATERMARKS
;
3162 if (gfpflags_to_migratetype(gfp_mask
) == MIGRATE_MOVABLE
)
3163 alloc_flags
|= ALLOC_CMA
;
3168 bool gfp_pfmemalloc_allowed(gfp_t gfp_mask
)
3170 return !!(gfp_to_alloc_flags(gfp_mask
) & ALLOC_NO_WATERMARKS
);
3173 static inline bool is_thp_gfp_mask(gfp_t gfp_mask
)
3175 return (gfp_mask
& (GFP_TRANSHUGE
| __GFP_KSWAPD_RECLAIM
)) == GFP_TRANSHUGE
;
3178 static inline struct page
*
3179 __alloc_pages_slowpath(gfp_t gfp_mask
, unsigned int order
,
3180 struct alloc_context
*ac
)
3182 bool can_direct_reclaim
= gfp_mask
& __GFP_DIRECT_RECLAIM
;
3183 struct page
*page
= NULL
;
3184 unsigned int alloc_flags
;
3185 unsigned long pages_reclaimed
= 0;
3186 unsigned long did_some_progress
;
3187 enum migrate_mode migration_mode
= MIGRATE_ASYNC
;
3188 bool deferred_compaction
= false;
3189 int contended_compaction
= COMPACT_CONTENDED_NONE
;
3192 * In the slowpath, we sanity check order to avoid ever trying to
3193 * reclaim >= MAX_ORDER areas which will never succeed. Callers may
3194 * be using allocators in order of preference for an area that is
3197 if (order
>= MAX_ORDER
) {
3198 WARN_ON_ONCE(!(gfp_mask
& __GFP_NOWARN
));
3203 * We also sanity check to catch abuse of atomic reserves being used by
3204 * callers that are not in atomic context.
3206 if (WARN_ON_ONCE((gfp_mask
& (__GFP_ATOMIC
|__GFP_DIRECT_RECLAIM
)) ==
3207 (__GFP_ATOMIC
|__GFP_DIRECT_RECLAIM
)))
3208 gfp_mask
&= ~__GFP_ATOMIC
;
3211 if (gfp_mask
& __GFP_KSWAPD_RECLAIM
)
3212 wake_all_kswapds(order
, ac
);
3215 * OK, we're below the kswapd watermark and have kicked background
3216 * reclaim. Now things get more complex, so set up alloc_flags according
3217 * to how we want to proceed.
3219 alloc_flags
= gfp_to_alloc_flags(gfp_mask
);
3221 /* This is the last chance, in general, before the goto nopage. */
3222 page
= get_page_from_freelist(gfp_mask
, order
,
3223 alloc_flags
& ~ALLOC_NO_WATERMARKS
, ac
);
3227 /* Allocate without watermarks if the context allows */
3228 if (alloc_flags
& ALLOC_NO_WATERMARKS
) {
3230 * Ignore mempolicies if ALLOC_NO_WATERMARKS on the grounds
3231 * the allocation is high priority and these type of
3232 * allocations are system rather than user orientated
3234 ac
->zonelist
= node_zonelist(numa_node_id(), gfp_mask
);
3235 page
= get_page_from_freelist(gfp_mask
, order
,
3236 ALLOC_NO_WATERMARKS
, ac
);
3241 /* Caller is not willing to reclaim, we can't balance anything */
3242 if (!can_direct_reclaim
) {
3244 * All existing users of the __GFP_NOFAIL are blockable, so warn
3245 * of any new users that actually allow this type of allocation
3248 WARN_ON_ONCE(gfp_mask
& __GFP_NOFAIL
);
3252 /* Avoid recursion of direct reclaim */
3253 if (current
->flags
& PF_MEMALLOC
) {
3255 * __GFP_NOFAIL request from this context is rather bizarre
3256 * because we cannot reclaim anything and only can loop waiting
3257 * for somebody to do a work for us.
3259 if (WARN_ON_ONCE(gfp_mask
& __GFP_NOFAIL
)) {
3266 /* Avoid allocations with no watermarks from looping endlessly */
3267 if (test_thread_flag(TIF_MEMDIE
) && !(gfp_mask
& __GFP_NOFAIL
))
3271 * Try direct compaction. The first pass is asynchronous. Subsequent
3272 * attempts after direct reclaim are synchronous
3274 page
= __alloc_pages_direct_compact(gfp_mask
, order
, alloc_flags
, ac
,
3276 &contended_compaction
,
3277 &deferred_compaction
);
3281 /* Checks for THP-specific high-order allocations */
3282 if (is_thp_gfp_mask(gfp_mask
)) {
3284 * If compaction is deferred for high-order allocations, it is
3285 * because sync compaction recently failed. If this is the case
3286 * and the caller requested a THP allocation, we do not want
3287 * to heavily disrupt the system, so we fail the allocation
3288 * instead of entering direct reclaim.
3290 if (deferred_compaction
)
3294 * In all zones where compaction was attempted (and not
3295 * deferred or skipped), lock contention has been detected.
3296 * For THP allocation we do not want to disrupt the others
3297 * so we fallback to base pages instead.
3299 if (contended_compaction
== COMPACT_CONTENDED_LOCK
)
3303 * If compaction was aborted due to need_resched(), we do not
3304 * want to further increase allocation latency, unless it is
3305 * khugepaged trying to collapse.
3307 if (contended_compaction
== COMPACT_CONTENDED_SCHED
3308 && !(current
->flags
& PF_KTHREAD
))
3313 * It can become very expensive to allocate transparent hugepages at
3314 * fault, so use asynchronous memory compaction for THP unless it is
3315 * khugepaged trying to collapse.
3317 if (!is_thp_gfp_mask(gfp_mask
) || (current
->flags
& PF_KTHREAD
))
3318 migration_mode
= MIGRATE_SYNC_LIGHT
;
3320 /* Try direct reclaim and then allocating */
3321 page
= __alloc_pages_direct_reclaim(gfp_mask
, order
, alloc_flags
, ac
,
3322 &did_some_progress
);
3326 /* Do not loop if specifically requested */
3327 if (gfp_mask
& __GFP_NORETRY
)
3330 /* Keep reclaiming pages as long as there is reasonable progress */
3331 pages_reclaimed
+= did_some_progress
;
3332 if ((did_some_progress
&& order
<= PAGE_ALLOC_COSTLY_ORDER
) ||
3333 ((gfp_mask
& __GFP_REPEAT
) && pages_reclaimed
< (1 << order
))) {
3334 /* Wait for some write requests to complete then retry */
3335 wait_iff_congested(ac
->preferred_zoneref
->zone
, BLK_RW_ASYNC
, HZ
/50);
3339 /* Reclaim has failed us, start killing things */
3340 page
= __alloc_pages_may_oom(gfp_mask
, order
, ac
, &did_some_progress
);
3344 /* Retry as long as the OOM killer is making progress */
3345 if (did_some_progress
)
3350 * High-order allocations do not necessarily loop after
3351 * direct reclaim and reclaim/compaction depends on compaction
3352 * being called after reclaim so call directly if necessary
3354 page
= __alloc_pages_direct_compact(gfp_mask
, order
, alloc_flags
,
3356 &contended_compaction
,
3357 &deferred_compaction
);
3361 warn_alloc_failed(gfp_mask
, order
, NULL
);
3367 * This is the 'heart' of the zoned buddy allocator.
3370 __alloc_pages_nodemask(gfp_t gfp_mask
, unsigned int order
,
3371 struct zonelist
*zonelist
, nodemask_t
*nodemask
)
3374 unsigned int cpuset_mems_cookie
;
3375 unsigned int alloc_flags
= ALLOC_WMARK_LOW
|ALLOC_FAIR
;
3376 gfp_t alloc_mask
= gfp_mask
; /* The gfp_t that was actually used for allocation */
3377 struct alloc_context ac
= {
3378 .high_zoneidx
= gfp_zone(gfp_mask
),
3379 .zonelist
= zonelist
,
3380 .nodemask
= nodemask
,
3381 .migratetype
= gfpflags_to_migratetype(gfp_mask
),
3384 if (cpusets_enabled()) {
3385 alloc_mask
|= __GFP_HARDWALL
;
3386 alloc_flags
|= ALLOC_CPUSET
;
3388 ac
.nodemask
= &cpuset_current_mems_allowed
;
3391 gfp_mask
&= gfp_allowed_mask
;
3393 lockdep_trace_alloc(gfp_mask
);
3395 might_sleep_if(gfp_mask
& __GFP_DIRECT_RECLAIM
);
3397 if (should_fail_alloc_page(gfp_mask
, order
))
3401 * Check the zones suitable for the gfp_mask contain at least one
3402 * valid zone. It's possible to have an empty zonelist as a result
3403 * of __GFP_THISNODE and a memoryless node
3405 if (unlikely(!zonelist
->_zonerefs
->zone
))
3408 if (IS_ENABLED(CONFIG_CMA
) && ac
.migratetype
== MIGRATE_MOVABLE
)
3409 alloc_flags
|= ALLOC_CMA
;
3412 cpuset_mems_cookie
= read_mems_allowed_begin();
3414 /* Dirty zone balancing only done in the fast path */
3415 ac
.spread_dirty_pages
= (gfp_mask
& __GFP_WRITE
);
3417 /* The preferred zone is used for statistics later */
3418 ac
.preferred_zoneref
= first_zones_zonelist(ac
.zonelist
,
3419 ac
.high_zoneidx
, ac
.nodemask
);
3420 if (!ac
.preferred_zoneref
) {
3425 /* First allocation attempt */
3426 page
= get_page_from_freelist(alloc_mask
, order
, alloc_flags
, &ac
);
3431 * Runtime PM, block IO and its error handling path can deadlock
3432 * because I/O on the device might not complete.
3434 alloc_mask
= memalloc_noio_flags(gfp_mask
);
3435 ac
.spread_dirty_pages
= false;
3437 page
= __alloc_pages_slowpath(alloc_mask
, order
, &ac
);
3441 * When updating a task's mems_allowed, it is possible to race with
3442 * parallel threads in such a way that an allocation can fail while
3443 * the mask is being updated. If a page allocation is about to fail,
3444 * check if the cpuset changed during allocation and if so, retry.
3446 if (unlikely(!page
&& read_mems_allowed_retry(cpuset_mems_cookie
))) {
3447 alloc_mask
= gfp_mask
;
3452 if (kmemcheck_enabled
&& page
)
3453 kmemcheck_pagealloc_alloc(page
, order
, gfp_mask
);
3455 trace_mm_page_alloc(page
, order
, alloc_mask
, ac
.migratetype
);
3459 EXPORT_SYMBOL(__alloc_pages_nodemask
);
3462 * Common helper functions.
3464 unsigned long __get_free_pages(gfp_t gfp_mask
, unsigned int order
)
3469 * __get_free_pages() returns a 32-bit address, which cannot represent
3472 VM_BUG_ON((gfp_mask
& __GFP_HIGHMEM
) != 0);
3474 page
= alloc_pages(gfp_mask
, order
);
3477 return (unsigned long) page_address(page
);
3479 EXPORT_SYMBOL(__get_free_pages
);
3481 unsigned long get_zeroed_page(gfp_t gfp_mask
)
3483 return __get_free_pages(gfp_mask
| __GFP_ZERO
, 0);
3485 EXPORT_SYMBOL(get_zeroed_page
);
3487 void __free_pages(struct page
*page
, unsigned int order
)
3489 if (put_page_testzero(page
)) {
3491 free_hot_cold_page(page
, false);
3493 __free_pages_ok(page
, order
);
3497 EXPORT_SYMBOL(__free_pages
);
3499 void free_pages(unsigned long addr
, unsigned int order
)
3502 VM_BUG_ON(!virt_addr_valid((void *)addr
));
3503 __free_pages(virt_to_page((void *)addr
), order
);
3507 EXPORT_SYMBOL(free_pages
);
3511 * An arbitrary-length arbitrary-offset area of memory which resides
3512 * within a 0 or higher order page. Multiple fragments within that page
3513 * are individually refcounted, in the page's reference counter.
3515 * The page_frag functions below provide a simple allocation framework for
3516 * page fragments. This is used by the network stack and network device
3517 * drivers to provide a backing region of memory for use as either an
3518 * sk_buff->head, or to be used in the "frags" portion of skb_shared_info.
3520 static struct page
*__page_frag_refill(struct page_frag_cache
*nc
,
3523 struct page
*page
= NULL
;
3524 gfp_t gfp
= gfp_mask
;
3526 #if (PAGE_SIZE < PAGE_FRAG_CACHE_MAX_SIZE)
3527 gfp_mask
|= __GFP_COMP
| __GFP_NOWARN
| __GFP_NORETRY
|
3529 page
= alloc_pages_node(NUMA_NO_NODE
, gfp_mask
,
3530 PAGE_FRAG_CACHE_MAX_ORDER
);
3531 nc
->size
= page
? PAGE_FRAG_CACHE_MAX_SIZE
: PAGE_SIZE
;
3533 if (unlikely(!page
))
3534 page
= alloc_pages_node(NUMA_NO_NODE
, gfp
, 0);
3536 nc
->va
= page
? page_address(page
) : NULL
;
3541 void *__alloc_page_frag(struct page_frag_cache
*nc
,
3542 unsigned int fragsz
, gfp_t gfp_mask
)
3544 unsigned int size
= PAGE_SIZE
;
3548 if (unlikely(!nc
->va
)) {
3550 page
= __page_frag_refill(nc
, gfp_mask
);
3554 #if (PAGE_SIZE < PAGE_FRAG_CACHE_MAX_SIZE)
3555 /* if size can vary use size else just use PAGE_SIZE */
3558 /* Even if we own the page, we do not use atomic_set().
3559 * This would break get_page_unless_zero() users.
3561 page_ref_add(page
, size
- 1);
3563 /* reset page count bias and offset to start of new frag */
3564 nc
->pfmemalloc
= page_is_pfmemalloc(page
);
3565 nc
->pagecnt_bias
= size
;
3569 offset
= nc
->offset
- fragsz
;
3570 if (unlikely(offset
< 0)) {
3571 page
= virt_to_page(nc
->va
);
3573 if (!page_ref_sub_and_test(page
, nc
->pagecnt_bias
))
3576 #if (PAGE_SIZE < PAGE_FRAG_CACHE_MAX_SIZE)
3577 /* if size can vary use size else just use PAGE_SIZE */
3580 /* OK, page count is 0, we can safely set it */
3581 set_page_count(page
, size
);
3583 /* reset page count bias and offset to start of new frag */
3584 nc
->pagecnt_bias
= size
;
3585 offset
= size
- fragsz
;
3589 nc
->offset
= offset
;
3591 return nc
->va
+ offset
;
3593 EXPORT_SYMBOL(__alloc_page_frag
);
3596 * Frees a page fragment allocated out of either a compound or order 0 page.
3598 void __free_page_frag(void *addr
)
3600 struct page
*page
= virt_to_head_page(addr
);
3602 if (unlikely(put_page_testzero(page
)))
3603 __free_pages_ok(page
, compound_order(page
));
3605 EXPORT_SYMBOL(__free_page_frag
);
3608 * alloc_kmem_pages charges newly allocated pages to the kmem resource counter
3609 * of the current memory cgroup if __GFP_ACCOUNT is set, other than that it is
3610 * equivalent to alloc_pages.
3612 * It should be used when the caller would like to use kmalloc, but since the
3613 * allocation is large, it has to fall back to the page allocator.
3615 struct page
*alloc_kmem_pages(gfp_t gfp_mask
, unsigned int order
)
3619 page
= alloc_pages(gfp_mask
, order
);
3620 if (page
&& memcg_kmem_charge(page
, gfp_mask
, order
) != 0) {
3621 __free_pages(page
, order
);
3627 struct page
*alloc_kmem_pages_node(int nid
, gfp_t gfp_mask
, unsigned int order
)
3631 page
= alloc_pages_node(nid
, gfp_mask
, order
);
3632 if (page
&& memcg_kmem_charge(page
, gfp_mask
, order
) != 0) {
3633 __free_pages(page
, order
);
3640 * __free_kmem_pages and free_kmem_pages will free pages allocated with
3643 void __free_kmem_pages(struct page
*page
, unsigned int order
)
3645 memcg_kmem_uncharge(page
, order
);
3646 __free_pages(page
, order
);
3649 void free_kmem_pages(unsigned long addr
, unsigned int order
)
3652 VM_BUG_ON(!virt_addr_valid((void *)addr
));
3653 __free_kmem_pages(virt_to_page((void *)addr
), order
);
3657 static void *make_alloc_exact(unsigned long addr
, unsigned int order
,
3661 unsigned long alloc_end
= addr
+ (PAGE_SIZE
<< order
);
3662 unsigned long used
= addr
+ PAGE_ALIGN(size
);
3664 split_page(virt_to_page((void *)addr
), order
);
3665 while (used
< alloc_end
) {
3670 return (void *)addr
;
3674 * alloc_pages_exact - allocate an exact number physically-contiguous pages.
3675 * @size: the number of bytes to allocate
3676 * @gfp_mask: GFP flags for the allocation
3678 * This function is similar to alloc_pages(), except that it allocates the
3679 * minimum number of pages to satisfy the request. alloc_pages() can only
3680 * allocate memory in power-of-two pages.
3682 * This function is also limited by MAX_ORDER.
3684 * Memory allocated by this function must be released by free_pages_exact().
3686 void *alloc_pages_exact(size_t size
, gfp_t gfp_mask
)
3688 unsigned int order
= get_order(size
);
3691 addr
= __get_free_pages(gfp_mask
, order
);
3692 return make_alloc_exact(addr
, order
, size
);
3694 EXPORT_SYMBOL(alloc_pages_exact
);
3697 * alloc_pages_exact_nid - allocate an exact number of physically-contiguous
3699 * @nid: the preferred node ID where memory should be allocated
3700 * @size: the number of bytes to allocate
3701 * @gfp_mask: GFP flags for the allocation
3703 * Like alloc_pages_exact(), but try to allocate on node nid first before falling
3706 void * __meminit
alloc_pages_exact_nid(int nid
, size_t size
, gfp_t gfp_mask
)
3708 unsigned int order
= get_order(size
);
3709 struct page
*p
= alloc_pages_node(nid
, gfp_mask
, order
);
3712 return make_alloc_exact((unsigned long)page_address(p
), order
, size
);
3716 * free_pages_exact - release memory allocated via alloc_pages_exact()
3717 * @virt: the value returned by alloc_pages_exact.
3718 * @size: size of allocation, same value as passed to alloc_pages_exact().
3720 * Release the memory allocated by a previous call to alloc_pages_exact.
3722 void free_pages_exact(void *virt
, size_t size
)
3724 unsigned long addr
= (unsigned long)virt
;
3725 unsigned long end
= addr
+ PAGE_ALIGN(size
);
3727 while (addr
< end
) {
3732 EXPORT_SYMBOL(free_pages_exact
);
3735 * nr_free_zone_pages - count number of pages beyond high watermark
3736 * @offset: The zone index of the highest zone
3738 * nr_free_zone_pages() counts the number of counts pages which are beyond the
3739 * high watermark within all zones at or below a given zone index. For each
3740 * zone, the number of pages is calculated as:
3741 * managed_pages - high_pages
3743 static unsigned long nr_free_zone_pages(int offset
)
3748 /* Just pick one node, since fallback list is circular */
3749 unsigned long sum
= 0;
3751 struct zonelist
*zonelist
= node_zonelist(numa_node_id(), GFP_KERNEL
);
3753 for_each_zone_zonelist(zone
, z
, zonelist
, offset
) {
3754 unsigned long size
= zone
->managed_pages
;
3755 unsigned long high
= high_wmark_pages(zone
);
3764 * nr_free_buffer_pages - count number of pages beyond high watermark
3766 * nr_free_buffer_pages() counts the number of pages which are beyond the high
3767 * watermark within ZONE_DMA and ZONE_NORMAL.
3769 unsigned long nr_free_buffer_pages(void)
3771 return nr_free_zone_pages(gfp_zone(GFP_USER
));
3773 EXPORT_SYMBOL_GPL(nr_free_buffer_pages
);
3776 * nr_free_pagecache_pages - count number of pages beyond high watermark
3778 * nr_free_pagecache_pages() counts the number of pages which are beyond the
3779 * high watermark within all zones.
3781 unsigned long nr_free_pagecache_pages(void)
3783 return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE
));
3786 static inline void show_node(struct zone
*zone
)
3788 if (IS_ENABLED(CONFIG_NUMA
))
3789 printk("Node %d ", zone_to_nid(zone
));
3792 long si_mem_available(void)
3795 unsigned long pagecache
;
3796 unsigned long wmark_low
= 0;
3797 unsigned long pages
[NR_LRU_LISTS
];
3801 for (lru
= LRU_BASE
; lru
< NR_LRU_LISTS
; lru
++)
3802 pages
[lru
] = global_page_state(NR_LRU_BASE
+ lru
);
3805 wmark_low
+= zone
->watermark
[WMARK_LOW
];
3808 * Estimate the amount of memory available for userspace allocations,
3809 * without causing swapping.
3811 available
= global_page_state(NR_FREE_PAGES
) - totalreserve_pages
;
3814 * Not all the page cache can be freed, otherwise the system will
3815 * start swapping. Assume at least half of the page cache, or the
3816 * low watermark worth of cache, needs to stay.
3818 pagecache
= pages
[LRU_ACTIVE_FILE
] + pages
[LRU_INACTIVE_FILE
];
3819 pagecache
-= min(pagecache
/ 2, wmark_low
);
3820 available
+= pagecache
;
3823 * Part of the reclaimable slab consists of items that are in use,
3824 * and cannot be freed. Cap this estimate at the low watermark.
3826 available
+= global_page_state(NR_SLAB_RECLAIMABLE
) -
3827 min(global_page_state(NR_SLAB_RECLAIMABLE
) / 2, wmark_low
);
3833 EXPORT_SYMBOL_GPL(si_mem_available
);
3835 void si_meminfo(struct sysinfo
*val
)
3837 val
->totalram
= totalram_pages
;
3838 val
->sharedram
= global_page_state(NR_SHMEM
);
3839 val
->freeram
= global_page_state(NR_FREE_PAGES
);
3840 val
->bufferram
= nr_blockdev_pages();
3841 val
->totalhigh
= totalhigh_pages
;
3842 val
->freehigh
= nr_free_highpages();
3843 val
->mem_unit
= PAGE_SIZE
;
3846 EXPORT_SYMBOL(si_meminfo
);
3849 void si_meminfo_node(struct sysinfo
*val
, int nid
)
3851 int zone_type
; /* needs to be signed */
3852 unsigned long managed_pages
= 0;
3853 unsigned long managed_highpages
= 0;
3854 unsigned long free_highpages
= 0;
3855 pg_data_t
*pgdat
= NODE_DATA(nid
);
3857 for (zone_type
= 0; zone_type
< MAX_NR_ZONES
; zone_type
++)
3858 managed_pages
+= pgdat
->node_zones
[zone_type
].managed_pages
;
3859 val
->totalram
= managed_pages
;
3860 val
->sharedram
= node_page_state(nid
, NR_SHMEM
);
3861 val
->freeram
= node_page_state(nid
, NR_FREE_PAGES
);
3862 #ifdef CONFIG_HIGHMEM
3863 for (zone_type
= 0; zone_type
< MAX_NR_ZONES
; zone_type
++) {
3864 struct zone
*zone
= &pgdat
->node_zones
[zone_type
];
3866 if (is_highmem(zone
)) {
3867 managed_highpages
+= zone
->managed_pages
;
3868 free_highpages
+= zone_page_state(zone
, NR_FREE_PAGES
);
3871 val
->totalhigh
= managed_highpages
;
3872 val
->freehigh
= free_highpages
;
3874 val
->totalhigh
= managed_highpages
;
3875 val
->freehigh
= free_highpages
;
3877 val
->mem_unit
= PAGE_SIZE
;
3882 * Determine whether the node should be displayed or not, depending on whether
3883 * SHOW_MEM_FILTER_NODES was passed to show_free_areas().
3885 bool skip_free_areas_node(unsigned int flags
, int nid
)
3888 unsigned int cpuset_mems_cookie
;
3890 if (!(flags
& SHOW_MEM_FILTER_NODES
))
3894 cpuset_mems_cookie
= read_mems_allowed_begin();
3895 ret
= !node_isset(nid
, cpuset_current_mems_allowed
);
3896 } while (read_mems_allowed_retry(cpuset_mems_cookie
));
3901 #define K(x) ((x) << (PAGE_SHIFT-10))
3903 static void show_migration_types(unsigned char type
)
3905 static const char types
[MIGRATE_TYPES
] = {
3906 [MIGRATE_UNMOVABLE
] = 'U',
3907 [MIGRATE_MOVABLE
] = 'M',
3908 [MIGRATE_RECLAIMABLE
] = 'E',
3909 [MIGRATE_HIGHATOMIC
] = 'H',
3911 [MIGRATE_CMA
] = 'C',
3913 #ifdef CONFIG_MEMORY_ISOLATION
3914 [MIGRATE_ISOLATE
] = 'I',
3917 char tmp
[MIGRATE_TYPES
+ 1];
3921 for (i
= 0; i
< MIGRATE_TYPES
; i
++) {
3922 if (type
& (1 << i
))
3927 printk("(%s) ", tmp
);
3931 * Show free area list (used inside shift_scroll-lock stuff)
3932 * We also calculate the percentage fragmentation. We do this by counting the
3933 * memory on each free list with the exception of the first item on the list.
3936 * SHOW_MEM_FILTER_NODES: suppress nodes that are not allowed by current's
3939 void show_free_areas(unsigned int filter
)
3941 unsigned long free_pcp
= 0;
3945 for_each_populated_zone(zone
) {
3946 if (skip_free_areas_node(filter
, zone_to_nid(zone
)))
3949 for_each_online_cpu(cpu
)
3950 free_pcp
+= per_cpu_ptr(zone
->pageset
, cpu
)->pcp
.count
;
3953 printk("active_anon:%lu inactive_anon:%lu isolated_anon:%lu\n"
3954 " active_file:%lu inactive_file:%lu isolated_file:%lu\n"
3955 " unevictable:%lu dirty:%lu writeback:%lu unstable:%lu\n"
3956 " slab_reclaimable:%lu slab_unreclaimable:%lu\n"
3957 " mapped:%lu shmem:%lu pagetables:%lu bounce:%lu\n"
3958 " free:%lu free_pcp:%lu free_cma:%lu\n",
3959 global_page_state(NR_ACTIVE_ANON
),
3960 global_page_state(NR_INACTIVE_ANON
),
3961 global_page_state(NR_ISOLATED_ANON
),
3962 global_page_state(NR_ACTIVE_FILE
),
3963 global_page_state(NR_INACTIVE_FILE
),
3964 global_page_state(NR_ISOLATED_FILE
),
3965 global_page_state(NR_UNEVICTABLE
),
3966 global_page_state(NR_FILE_DIRTY
),
3967 global_page_state(NR_WRITEBACK
),
3968 global_page_state(NR_UNSTABLE_NFS
),
3969 global_page_state(NR_SLAB_RECLAIMABLE
),
3970 global_page_state(NR_SLAB_UNRECLAIMABLE
),
3971 global_page_state(NR_FILE_MAPPED
),
3972 global_page_state(NR_SHMEM
),
3973 global_page_state(NR_PAGETABLE
),
3974 global_page_state(NR_BOUNCE
),
3975 global_page_state(NR_FREE_PAGES
),
3977 global_page_state(NR_FREE_CMA_PAGES
));
3979 for_each_populated_zone(zone
) {
3982 if (skip_free_areas_node(filter
, zone_to_nid(zone
)))
3986 for_each_online_cpu(cpu
)
3987 free_pcp
+= per_cpu_ptr(zone
->pageset
, cpu
)->pcp
.count
;
3995 " active_anon:%lukB"
3996 " inactive_anon:%lukB"
3997 " active_file:%lukB"
3998 " inactive_file:%lukB"
3999 " unevictable:%lukB"
4000 " isolated(anon):%lukB"
4001 " isolated(file):%lukB"
4009 " slab_reclaimable:%lukB"
4010 " slab_unreclaimable:%lukB"
4011 " kernel_stack:%lukB"
4018 " writeback_tmp:%lukB"
4019 " pages_scanned:%lu"
4020 " all_unreclaimable? %s"
4023 K(zone_page_state(zone
, NR_FREE_PAGES
)),
4024 K(min_wmark_pages(zone
)),
4025 K(low_wmark_pages(zone
)),
4026 K(high_wmark_pages(zone
)),
4027 K(zone_page_state(zone
, NR_ACTIVE_ANON
)),
4028 K(zone_page_state(zone
, NR_INACTIVE_ANON
)),
4029 K(zone_page_state(zone
, NR_ACTIVE_FILE
)),
4030 K(zone_page_state(zone
, NR_INACTIVE_FILE
)),
4031 K(zone_page_state(zone
, NR_UNEVICTABLE
)),
4032 K(zone_page_state(zone
, NR_ISOLATED_ANON
)),
4033 K(zone_page_state(zone
, NR_ISOLATED_FILE
)),
4034 K(zone
->present_pages
),
4035 K(zone
->managed_pages
),
4036 K(zone_page_state(zone
, NR_MLOCK
)),
4037 K(zone_page_state(zone
, NR_FILE_DIRTY
)),
4038 K(zone_page_state(zone
, NR_WRITEBACK
)),
4039 K(zone_page_state(zone
, NR_FILE_MAPPED
)),
4040 K(zone_page_state(zone
, NR_SHMEM
)),
4041 K(zone_page_state(zone
, NR_SLAB_RECLAIMABLE
)),
4042 K(zone_page_state(zone
, NR_SLAB_UNRECLAIMABLE
)),
4043 zone_page_state(zone
, NR_KERNEL_STACK
) *
4045 K(zone_page_state(zone
, NR_PAGETABLE
)),
4046 K(zone_page_state(zone
, NR_UNSTABLE_NFS
)),
4047 K(zone_page_state(zone
, NR_BOUNCE
)),
4049 K(this_cpu_read(zone
->pageset
->pcp
.count
)),
4050 K(zone_page_state(zone
, NR_FREE_CMA_PAGES
)),
4051 K(zone_page_state(zone
, NR_WRITEBACK_TEMP
)),
4052 K(zone_page_state(zone
, NR_PAGES_SCANNED
)),
4053 (!zone_reclaimable(zone
) ? "yes" : "no")
4055 printk("lowmem_reserve[]:");
4056 for (i
= 0; i
< MAX_NR_ZONES
; i
++)
4057 printk(" %ld", zone
->lowmem_reserve
[i
]);
4061 for_each_populated_zone(zone
) {
4063 unsigned long nr
[MAX_ORDER
], flags
, total
= 0;
4064 unsigned char types
[MAX_ORDER
];
4066 if (skip_free_areas_node(filter
, zone_to_nid(zone
)))
4069 printk("%s: ", zone
->name
);
4071 spin_lock_irqsave(&zone
->lock
, flags
);
4072 for (order
= 0; order
< MAX_ORDER
; order
++) {
4073 struct free_area
*area
= &zone
->free_area
[order
];
4076 nr
[order
] = area
->nr_free
;
4077 total
+= nr
[order
] << order
;
4080 for (type
= 0; type
< MIGRATE_TYPES
; type
++) {
4081 if (!list_empty(&area
->free_list
[type
]))
4082 types
[order
] |= 1 << type
;
4085 spin_unlock_irqrestore(&zone
->lock
, flags
);
4086 for (order
= 0; order
< MAX_ORDER
; order
++) {
4087 printk("%lu*%lukB ", nr
[order
], K(1UL) << order
);
4089 show_migration_types(types
[order
]);
4091 printk("= %lukB\n", K(total
));
4094 hugetlb_show_meminfo();
4096 printk("%ld total pagecache pages\n", global_page_state(NR_FILE_PAGES
));
4098 show_swap_cache_info();
4101 static void zoneref_set_zone(struct zone
*zone
, struct zoneref
*zoneref
)
4103 zoneref
->zone
= zone
;
4104 zoneref
->zone_idx
= zone_idx(zone
);
4108 * Builds allocation fallback zone lists.
4110 * Add all populated zones of a node to the zonelist.
4112 static int build_zonelists_node(pg_data_t
*pgdat
, struct zonelist
*zonelist
,
4116 enum zone_type zone_type
= MAX_NR_ZONES
;
4120 zone
= pgdat
->node_zones
+ zone_type
;
4121 if (populated_zone(zone
)) {
4122 zoneref_set_zone(zone
,
4123 &zonelist
->_zonerefs
[nr_zones
++]);
4124 check_highest_zone(zone_type
);
4126 } while (zone_type
);
4134 * 0 = automatic detection of better ordering.
4135 * 1 = order by ([node] distance, -zonetype)
4136 * 2 = order by (-zonetype, [node] distance)
4138 * If not NUMA, ZONELIST_ORDER_ZONE and ZONELIST_ORDER_NODE will create
4139 * the same zonelist. So only NUMA can configure this param.
4141 #define ZONELIST_ORDER_DEFAULT 0
4142 #define ZONELIST_ORDER_NODE 1
4143 #define ZONELIST_ORDER_ZONE 2
4145 /* zonelist order in the kernel.
4146 * set_zonelist_order() will set this to NODE or ZONE.
4148 static int current_zonelist_order
= ZONELIST_ORDER_DEFAULT
;
4149 static char zonelist_order_name
[3][8] = {"Default", "Node", "Zone"};
4153 /* The value user specified ....changed by config */
4154 static int user_zonelist_order
= ZONELIST_ORDER_DEFAULT
;
4155 /* string for sysctl */
4156 #define NUMA_ZONELIST_ORDER_LEN 16
4157 char numa_zonelist_order
[16] = "default";
4160 * interface for configure zonelist ordering.
4161 * command line option "numa_zonelist_order"
4162 * = "[dD]efault - default, automatic configuration.
4163 * = "[nN]ode - order by node locality, then by zone within node
4164 * = "[zZ]one - order by zone, then by locality within zone
4167 static int __parse_numa_zonelist_order(char *s
)
4169 if (*s
== 'd' || *s
== 'D') {
4170 user_zonelist_order
= ZONELIST_ORDER_DEFAULT
;
4171 } else if (*s
== 'n' || *s
== 'N') {
4172 user_zonelist_order
= ZONELIST_ORDER_NODE
;
4173 } else if (*s
== 'z' || *s
== 'Z') {
4174 user_zonelist_order
= ZONELIST_ORDER_ZONE
;
4176 pr_warn("Ignoring invalid numa_zonelist_order value: %s\n", s
);
4182 static __init
int setup_numa_zonelist_order(char *s
)
4189 ret
= __parse_numa_zonelist_order(s
);
4191 strlcpy(numa_zonelist_order
, s
, NUMA_ZONELIST_ORDER_LEN
);
4195 early_param("numa_zonelist_order", setup_numa_zonelist_order
);
4198 * sysctl handler for numa_zonelist_order
4200 int numa_zonelist_order_handler(struct ctl_table
*table
, int write
,
4201 void __user
*buffer
, size_t *length
,
4204 char saved_string
[NUMA_ZONELIST_ORDER_LEN
];
4206 static DEFINE_MUTEX(zl_order_mutex
);
4208 mutex_lock(&zl_order_mutex
);
4210 if (strlen((char *)table
->data
) >= NUMA_ZONELIST_ORDER_LEN
) {
4214 strcpy(saved_string
, (char *)table
->data
);
4216 ret
= proc_dostring(table
, write
, buffer
, length
, ppos
);
4220 int oldval
= user_zonelist_order
;
4222 ret
= __parse_numa_zonelist_order((char *)table
->data
);
4225 * bogus value. restore saved string
4227 strncpy((char *)table
->data
, saved_string
,
4228 NUMA_ZONELIST_ORDER_LEN
);
4229 user_zonelist_order
= oldval
;
4230 } else if (oldval
!= user_zonelist_order
) {
4231 mutex_lock(&zonelists_mutex
);
4232 build_all_zonelists(NULL
, NULL
);
4233 mutex_unlock(&zonelists_mutex
);
4237 mutex_unlock(&zl_order_mutex
);
4242 #define MAX_NODE_LOAD (nr_online_nodes)
4243 static int node_load
[MAX_NUMNODES
];
4246 * find_next_best_node - find the next node that should appear in a given node's fallback list
4247 * @node: node whose fallback list we're appending
4248 * @used_node_mask: nodemask_t of already used nodes
4250 * We use a number of factors to determine which is the next node that should
4251 * appear on a given node's fallback list. The node should not have appeared
4252 * already in @node's fallback list, and it should be the next closest node
4253 * according to the distance array (which contains arbitrary distance values
4254 * from each node to each node in the system), and should also prefer nodes
4255 * with no CPUs, since presumably they'll have very little allocation pressure
4256 * on them otherwise.
4257 * It returns -1 if no node is found.
4259 static int find_next_best_node(int node
, nodemask_t
*used_node_mask
)
4262 int min_val
= INT_MAX
;
4263 int best_node
= NUMA_NO_NODE
;
4264 const struct cpumask
*tmp
= cpumask_of_node(0);
4266 /* Use the local node if we haven't already */
4267 if (!node_isset(node
, *used_node_mask
)) {
4268 node_set(node
, *used_node_mask
);
4272 for_each_node_state(n
, N_MEMORY
) {
4274 /* Don't want a node to appear more than once */
4275 if (node_isset(n
, *used_node_mask
))
4278 /* Use the distance array to find the distance */
4279 val
= node_distance(node
, n
);
4281 /* Penalize nodes under us ("prefer the next node") */
4284 /* Give preference to headless and unused nodes */
4285 tmp
= cpumask_of_node(n
);
4286 if (!cpumask_empty(tmp
))
4287 val
+= PENALTY_FOR_NODE_WITH_CPUS
;
4289 /* Slight preference for less loaded node */
4290 val
*= (MAX_NODE_LOAD
*MAX_NUMNODES
);
4291 val
+= node_load
[n
];
4293 if (val
< min_val
) {
4300 node_set(best_node
, *used_node_mask
);
4307 * Build zonelists ordered by node and zones within node.
4308 * This results in maximum locality--normal zone overflows into local
4309 * DMA zone, if any--but risks exhausting DMA zone.
4311 static void build_zonelists_in_node_order(pg_data_t
*pgdat
, int node
)
4314 struct zonelist
*zonelist
;
4316 zonelist
= &pgdat
->node_zonelists
[0];
4317 for (j
= 0; zonelist
->_zonerefs
[j
].zone
!= NULL
; j
++)
4319 j
= build_zonelists_node(NODE_DATA(node
), zonelist
, j
);
4320 zonelist
->_zonerefs
[j
].zone
= NULL
;
4321 zonelist
->_zonerefs
[j
].zone_idx
= 0;
4325 * Build gfp_thisnode zonelists
4327 static void build_thisnode_zonelists(pg_data_t
*pgdat
)
4330 struct zonelist
*zonelist
;
4332 zonelist
= &pgdat
->node_zonelists
[1];
4333 j
= build_zonelists_node(pgdat
, zonelist
, 0);
4334 zonelist
->_zonerefs
[j
].zone
= NULL
;
4335 zonelist
->_zonerefs
[j
].zone_idx
= 0;
4339 * Build zonelists ordered by zone and nodes within zones.
4340 * This results in conserving DMA zone[s] until all Normal memory is
4341 * exhausted, but results in overflowing to remote node while memory
4342 * may still exist in local DMA zone.
4344 static int node_order
[MAX_NUMNODES
];
4346 static void build_zonelists_in_zone_order(pg_data_t
*pgdat
, int nr_nodes
)
4349 int zone_type
; /* needs to be signed */
4351 struct zonelist
*zonelist
;
4353 zonelist
= &pgdat
->node_zonelists
[0];
4355 for (zone_type
= MAX_NR_ZONES
- 1; zone_type
>= 0; zone_type
--) {
4356 for (j
= 0; j
< nr_nodes
; j
++) {
4357 node
= node_order
[j
];
4358 z
= &NODE_DATA(node
)->node_zones
[zone_type
];
4359 if (populated_zone(z
)) {
4361 &zonelist
->_zonerefs
[pos
++]);
4362 check_highest_zone(zone_type
);
4366 zonelist
->_zonerefs
[pos
].zone
= NULL
;
4367 zonelist
->_zonerefs
[pos
].zone_idx
= 0;
4370 #if defined(CONFIG_64BIT)
4372 * Devices that require DMA32/DMA are relatively rare and do not justify a
4373 * penalty to every machine in case the specialised case applies. Default
4374 * to Node-ordering on 64-bit NUMA machines
4376 static int default_zonelist_order(void)
4378 return ZONELIST_ORDER_NODE
;
4382 * On 32-bit, the Normal zone needs to be preserved for allocations accessible
4383 * by the kernel. If processes running on node 0 deplete the low memory zone
4384 * then reclaim will occur more frequency increasing stalls and potentially
4385 * be easier to OOM if a large percentage of the zone is under writeback or
4386 * dirty. The problem is significantly worse if CONFIG_HIGHPTE is not set.
4387 * Hence, default to zone ordering on 32-bit.
4389 static int default_zonelist_order(void)
4391 return ZONELIST_ORDER_ZONE
;
4393 #endif /* CONFIG_64BIT */
4395 static void set_zonelist_order(void)
4397 if (user_zonelist_order
== ZONELIST_ORDER_DEFAULT
)
4398 current_zonelist_order
= default_zonelist_order();
4400 current_zonelist_order
= user_zonelist_order
;
4403 static void build_zonelists(pg_data_t
*pgdat
)
4406 nodemask_t used_mask
;
4407 int local_node
, prev_node
;
4408 struct zonelist
*zonelist
;
4409 unsigned int order
= current_zonelist_order
;
4411 /* initialize zonelists */
4412 for (i
= 0; i
< MAX_ZONELISTS
; i
++) {
4413 zonelist
= pgdat
->node_zonelists
+ i
;
4414 zonelist
->_zonerefs
[0].zone
= NULL
;
4415 zonelist
->_zonerefs
[0].zone_idx
= 0;
4418 /* NUMA-aware ordering of nodes */
4419 local_node
= pgdat
->node_id
;
4420 load
= nr_online_nodes
;
4421 prev_node
= local_node
;
4422 nodes_clear(used_mask
);
4424 memset(node_order
, 0, sizeof(node_order
));
4427 while ((node
= find_next_best_node(local_node
, &used_mask
)) >= 0) {
4429 * We don't want to pressure a particular node.
4430 * So adding penalty to the first node in same
4431 * distance group to make it round-robin.
4433 if (node_distance(local_node
, node
) !=
4434 node_distance(local_node
, prev_node
))
4435 node_load
[node
] = load
;
4439 if (order
== ZONELIST_ORDER_NODE
)
4440 build_zonelists_in_node_order(pgdat
, node
);
4442 node_order
[i
++] = node
; /* remember order */
4445 if (order
== ZONELIST_ORDER_ZONE
) {
4446 /* calculate node order -- i.e., DMA last! */
4447 build_zonelists_in_zone_order(pgdat
, i
);
4450 build_thisnode_zonelists(pgdat
);
4453 #ifdef CONFIG_HAVE_MEMORYLESS_NODES
4455 * Return node id of node used for "local" allocations.
4456 * I.e., first node id of first zone in arg node's generic zonelist.
4457 * Used for initializing percpu 'numa_mem', which is used primarily
4458 * for kernel allocations, so use GFP_KERNEL flags to locate zonelist.
4460 int local_memory_node(int node
)
4464 z
= first_zones_zonelist(node_zonelist(node
, GFP_KERNEL
),
4465 gfp_zone(GFP_KERNEL
),
4467 return z
->zone
->node
;
4471 #else /* CONFIG_NUMA */
4473 static void set_zonelist_order(void)
4475 current_zonelist_order
= ZONELIST_ORDER_ZONE
;
4478 static void build_zonelists(pg_data_t
*pgdat
)
4480 int node
, local_node
;
4482 struct zonelist
*zonelist
;
4484 local_node
= pgdat
->node_id
;
4486 zonelist
= &pgdat
->node_zonelists
[0];
4487 j
= build_zonelists_node(pgdat
, zonelist
, 0);
4490 * Now we build the zonelist so that it contains the zones
4491 * of all the other nodes.
4492 * We don't want to pressure a particular node, so when
4493 * building the zones for node N, we make sure that the
4494 * zones coming right after the local ones are those from
4495 * node N+1 (modulo N)
4497 for (node
= local_node
+ 1; node
< MAX_NUMNODES
; node
++) {
4498 if (!node_online(node
))
4500 j
= build_zonelists_node(NODE_DATA(node
), zonelist
, j
);
4502 for (node
= 0; node
< local_node
; node
++) {
4503 if (!node_online(node
))
4505 j
= build_zonelists_node(NODE_DATA(node
), zonelist
, j
);
4508 zonelist
->_zonerefs
[j
].zone
= NULL
;
4509 zonelist
->_zonerefs
[j
].zone_idx
= 0;
4512 #endif /* CONFIG_NUMA */
4515 * Boot pageset table. One per cpu which is going to be used for all
4516 * zones and all nodes. The parameters will be set in such a way
4517 * that an item put on a list will immediately be handed over to
4518 * the buddy list. This is safe since pageset manipulation is done
4519 * with interrupts disabled.
4521 * The boot_pagesets must be kept even after bootup is complete for
4522 * unused processors and/or zones. They do play a role for bootstrapping
4523 * hotplugged processors.
4525 * zoneinfo_show() and maybe other functions do
4526 * not check if the processor is online before following the pageset pointer.
4527 * Other parts of the kernel may not check if the zone is available.
4529 static void setup_pageset(struct per_cpu_pageset
*p
, unsigned long batch
);
4530 static DEFINE_PER_CPU(struct per_cpu_pageset
, boot_pageset
);
4531 static void setup_zone_pageset(struct zone
*zone
);
4534 * Global mutex to protect against size modification of zonelists
4535 * as well as to serialize pageset setup for the new populated zone.
4537 DEFINE_MUTEX(zonelists_mutex
);
4539 /* return values int ....just for stop_machine() */
4540 static int __build_all_zonelists(void *data
)
4544 pg_data_t
*self
= data
;
4547 memset(node_load
, 0, sizeof(node_load
));
4550 if (self
&& !node_online(self
->node_id
)) {
4551 build_zonelists(self
);
4554 for_each_online_node(nid
) {
4555 pg_data_t
*pgdat
= NODE_DATA(nid
);
4557 build_zonelists(pgdat
);
4561 * Initialize the boot_pagesets that are going to be used
4562 * for bootstrapping processors. The real pagesets for
4563 * each zone will be allocated later when the per cpu
4564 * allocator is available.
4566 * boot_pagesets are used also for bootstrapping offline
4567 * cpus if the system is already booted because the pagesets
4568 * are needed to initialize allocators on a specific cpu too.
4569 * F.e. the percpu allocator needs the page allocator which
4570 * needs the percpu allocator in order to allocate its pagesets
4571 * (a chicken-egg dilemma).
4573 for_each_possible_cpu(cpu
) {
4574 setup_pageset(&per_cpu(boot_pageset
, cpu
), 0);
4576 #ifdef CONFIG_HAVE_MEMORYLESS_NODES
4578 * We now know the "local memory node" for each node--
4579 * i.e., the node of the first zone in the generic zonelist.
4580 * Set up numa_mem percpu variable for on-line cpus. During
4581 * boot, only the boot cpu should be on-line; we'll init the
4582 * secondary cpus' numa_mem as they come on-line. During
4583 * node/memory hotplug, we'll fixup all on-line cpus.
4585 if (cpu_online(cpu
))
4586 set_cpu_numa_mem(cpu
, local_memory_node(cpu_to_node(cpu
)));
4593 static noinline
void __init
4594 build_all_zonelists_init(void)
4596 __build_all_zonelists(NULL
);
4597 mminit_verify_zonelist();
4598 cpuset_init_current_mems_allowed();
4602 * Called with zonelists_mutex held always
4603 * unless system_state == SYSTEM_BOOTING.
4605 * __ref due to (1) call of __meminit annotated setup_zone_pageset
4606 * [we're only called with non-NULL zone through __meminit paths] and
4607 * (2) call of __init annotated helper build_all_zonelists_init
4608 * [protected by SYSTEM_BOOTING].
4610 void __ref
build_all_zonelists(pg_data_t
*pgdat
, struct zone
*zone
)
4612 set_zonelist_order();
4614 if (system_state
== SYSTEM_BOOTING
) {
4615 build_all_zonelists_init();
4617 #ifdef CONFIG_MEMORY_HOTPLUG
4619 setup_zone_pageset(zone
);
4621 /* we have to stop all cpus to guarantee there is no user
4623 stop_machine(__build_all_zonelists
, pgdat
, NULL
);
4624 /* cpuset refresh routine should be here */
4626 vm_total_pages
= nr_free_pagecache_pages();
4628 * Disable grouping by mobility if the number of pages in the
4629 * system is too low to allow the mechanism to work. It would be
4630 * more accurate, but expensive to check per-zone. This check is
4631 * made on memory-hotadd so a system can start with mobility
4632 * disabled and enable it later
4634 if (vm_total_pages
< (pageblock_nr_pages
* MIGRATE_TYPES
))
4635 page_group_by_mobility_disabled
= 1;
4637 page_group_by_mobility_disabled
= 0;
4639 pr_info("Built %i zonelists in %s order, mobility grouping %s. Total pages: %ld\n",
4641 zonelist_order_name
[current_zonelist_order
],
4642 page_group_by_mobility_disabled
? "off" : "on",
4645 pr_info("Policy zone: %s\n", zone_names
[policy_zone
]);
4650 * Helper functions to size the waitqueue hash table.
4651 * Essentially these want to choose hash table sizes sufficiently
4652 * large so that collisions trying to wait on pages are rare.
4653 * But in fact, the number of active page waitqueues on typical
4654 * systems is ridiculously low, less than 200. So this is even
4655 * conservative, even though it seems large.
4657 * The constant PAGES_PER_WAITQUEUE specifies the ratio of pages to
4658 * waitqueues, i.e. the size of the waitq table given the number of pages.
4660 #define PAGES_PER_WAITQUEUE 256
4662 #ifndef CONFIG_MEMORY_HOTPLUG
4663 static inline unsigned long wait_table_hash_nr_entries(unsigned long pages
)
4665 unsigned long size
= 1;
4667 pages
/= PAGES_PER_WAITQUEUE
;
4669 while (size
< pages
)
4673 * Once we have dozens or even hundreds of threads sleeping
4674 * on IO we've got bigger problems than wait queue collision.
4675 * Limit the size of the wait table to a reasonable size.
4677 size
= min(size
, 4096UL);
4679 return max(size
, 4UL);
4683 * A zone's size might be changed by hot-add, so it is not possible to determine
4684 * a suitable size for its wait_table. So we use the maximum size now.
4686 * The max wait table size = 4096 x sizeof(wait_queue_head_t). ie:
4688 * i386 (preemption config) : 4096 x 16 = 64Kbyte.
4689 * ia64, x86-64 (no preemption): 4096 x 20 = 80Kbyte.
4690 * ia64, x86-64 (preemption) : 4096 x 24 = 96Kbyte.
4692 * The maximum entries are prepared when a zone's memory is (512K + 256) pages
4693 * or more by the traditional way. (See above). It equals:
4695 * i386, x86-64, powerpc(4K page size) : = ( 2G + 1M)byte.
4696 * ia64(16K page size) : = ( 8G + 4M)byte.
4697 * powerpc (64K page size) : = (32G +16M)byte.
4699 static inline unsigned long wait_table_hash_nr_entries(unsigned long pages
)
4706 * This is an integer logarithm so that shifts can be used later
4707 * to extract the more random high bits from the multiplicative
4708 * hash function before the remainder is taken.
4710 static inline unsigned long wait_table_bits(unsigned long size
)
4716 * Initially all pages are reserved - free ones are freed
4717 * up by free_all_bootmem() once the early boot process is
4718 * done. Non-atomic initialization, single-pass.
4720 void __meminit
memmap_init_zone(unsigned long size
, int nid
, unsigned long zone
,
4721 unsigned long start_pfn
, enum memmap_context context
)
4723 struct vmem_altmap
*altmap
= to_vmem_altmap(__pfn_to_phys(start_pfn
));
4724 unsigned long end_pfn
= start_pfn
+ size
;
4725 pg_data_t
*pgdat
= NODE_DATA(nid
);
4727 unsigned long nr_initialised
= 0;
4728 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
4729 struct memblock_region
*r
= NULL
, *tmp
;
4732 if (highest_memmap_pfn
< end_pfn
- 1)
4733 highest_memmap_pfn
= end_pfn
- 1;
4736 * Honor reservation requested by the driver for this ZONE_DEVICE
4739 if (altmap
&& start_pfn
== altmap
->base_pfn
)
4740 start_pfn
+= altmap
->reserve
;
4742 for (pfn
= start_pfn
; pfn
< end_pfn
; pfn
++) {
4744 * There can be holes in boot-time mem_map[]s handed to this
4745 * function. They do not exist on hotplugged memory.
4747 if (context
!= MEMMAP_EARLY
)
4750 if (!early_pfn_valid(pfn
))
4752 if (!early_pfn_in_nid(pfn
, nid
))
4754 if (!update_defer_init(pgdat
, pfn
, end_pfn
, &nr_initialised
))
4757 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
4759 * If not mirrored_kernelcore and ZONE_MOVABLE exists, range
4760 * from zone_movable_pfn[nid] to end of each node should be
4761 * ZONE_MOVABLE not ZONE_NORMAL. skip it.
4763 if (!mirrored_kernelcore
&& zone_movable_pfn
[nid
])
4764 if (zone
== ZONE_NORMAL
&& pfn
>= zone_movable_pfn
[nid
])
4768 * Check given memblock attribute by firmware which can affect
4769 * kernel memory layout. If zone==ZONE_MOVABLE but memory is
4770 * mirrored, it's an overlapped memmap init. skip it.
4772 if (mirrored_kernelcore
&& zone
== ZONE_MOVABLE
) {
4773 if (!r
|| pfn
>= memblock_region_memory_end_pfn(r
)) {
4774 for_each_memblock(memory
, tmp
)
4775 if (pfn
< memblock_region_memory_end_pfn(tmp
))
4779 if (pfn
>= memblock_region_memory_base_pfn(r
) &&
4780 memblock_is_mirror(r
)) {
4781 /* already initialized as NORMAL */
4782 pfn
= memblock_region_memory_end_pfn(r
);
4790 * Mark the block movable so that blocks are reserved for
4791 * movable at startup. This will force kernel allocations
4792 * to reserve their blocks rather than leaking throughout
4793 * the address space during boot when many long-lived
4794 * kernel allocations are made.
4796 * bitmap is created for zone's valid pfn range. but memmap
4797 * can be created for invalid pages (for alignment)
4798 * check here not to call set_pageblock_migratetype() against
4801 if (!(pfn
& (pageblock_nr_pages
- 1))) {
4802 struct page
*page
= pfn_to_page(pfn
);
4804 __init_single_page(page
, pfn
, zone
, nid
);
4805 set_pageblock_migratetype(page
, MIGRATE_MOVABLE
);
4807 __init_single_pfn(pfn
, zone
, nid
);
4812 static void __meminit
zone_init_free_lists(struct zone
*zone
)
4814 unsigned int order
, t
;
4815 for_each_migratetype_order(order
, t
) {
4816 INIT_LIST_HEAD(&zone
->free_area
[order
].free_list
[t
]);
4817 zone
->free_area
[order
].nr_free
= 0;
4821 #ifndef __HAVE_ARCH_MEMMAP_INIT
4822 #define memmap_init(size, nid, zone, start_pfn) \
4823 memmap_init_zone((size), (nid), (zone), (start_pfn), MEMMAP_EARLY)
4826 static int zone_batchsize(struct zone
*zone
)
4832 * The per-cpu-pages pools are set to around 1000th of the
4833 * size of the zone. But no more than 1/2 of a meg.
4835 * OK, so we don't know how big the cache is. So guess.
4837 batch
= zone
->managed_pages
/ 1024;
4838 if (batch
* PAGE_SIZE
> 512 * 1024)
4839 batch
= (512 * 1024) / PAGE_SIZE
;
4840 batch
/= 4; /* We effectively *= 4 below */
4845 * Clamp the batch to a 2^n - 1 value. Having a power
4846 * of 2 value was found to be more likely to have
4847 * suboptimal cache aliasing properties in some cases.
4849 * For example if 2 tasks are alternately allocating
4850 * batches of pages, one task can end up with a lot
4851 * of pages of one half of the possible page colors
4852 * and the other with pages of the other colors.
4854 batch
= rounddown_pow_of_two(batch
+ batch
/2) - 1;
4859 /* The deferral and batching of frees should be suppressed under NOMMU
4862 * The problem is that NOMMU needs to be able to allocate large chunks
4863 * of contiguous memory as there's no hardware page translation to
4864 * assemble apparent contiguous memory from discontiguous pages.
4866 * Queueing large contiguous runs of pages for batching, however,
4867 * causes the pages to actually be freed in smaller chunks. As there
4868 * can be a significant delay between the individual batches being
4869 * recycled, this leads to the once large chunks of space being
4870 * fragmented and becoming unavailable for high-order allocations.
4877 * pcp->high and pcp->batch values are related and dependent on one another:
4878 * ->batch must never be higher then ->high.
4879 * The following function updates them in a safe manner without read side
4882 * Any new users of pcp->batch and pcp->high should ensure they can cope with
4883 * those fields changing asynchronously (acording the the above rule).
4885 * mutex_is_locked(&pcp_batch_high_lock) required when calling this function
4886 * outside of boot time (or some other assurance that no concurrent updaters
4889 static void pageset_update(struct per_cpu_pages
*pcp
, unsigned long high
,
4890 unsigned long batch
)
4892 /* start with a fail safe value for batch */
4896 /* Update high, then batch, in order */
4903 /* a companion to pageset_set_high() */
4904 static void pageset_set_batch(struct per_cpu_pageset
*p
, unsigned long batch
)
4906 pageset_update(&p
->pcp
, 6 * batch
, max(1UL, 1 * batch
));
4909 static void pageset_init(struct per_cpu_pageset
*p
)
4911 struct per_cpu_pages
*pcp
;
4914 memset(p
, 0, sizeof(*p
));
4918 for (migratetype
= 0; migratetype
< MIGRATE_PCPTYPES
; migratetype
++)
4919 INIT_LIST_HEAD(&pcp
->lists
[migratetype
]);
4922 static void setup_pageset(struct per_cpu_pageset
*p
, unsigned long batch
)
4925 pageset_set_batch(p
, batch
);
4929 * pageset_set_high() sets the high water mark for hot per_cpu_pagelist
4930 * to the value high for the pageset p.
4932 static void pageset_set_high(struct per_cpu_pageset
*p
,
4935 unsigned long batch
= max(1UL, high
/ 4);
4936 if ((high
/ 4) > (PAGE_SHIFT
* 8))
4937 batch
= PAGE_SHIFT
* 8;
4939 pageset_update(&p
->pcp
, high
, batch
);
4942 static void pageset_set_high_and_batch(struct zone
*zone
,
4943 struct per_cpu_pageset
*pcp
)
4945 if (percpu_pagelist_fraction
)
4946 pageset_set_high(pcp
,
4947 (zone
->managed_pages
/
4948 percpu_pagelist_fraction
));
4950 pageset_set_batch(pcp
, zone_batchsize(zone
));
4953 static void __meminit
zone_pageset_init(struct zone
*zone
, int cpu
)
4955 struct per_cpu_pageset
*pcp
= per_cpu_ptr(zone
->pageset
, cpu
);
4958 pageset_set_high_and_batch(zone
, pcp
);
4961 static void __meminit
setup_zone_pageset(struct zone
*zone
)
4964 zone
->pageset
= alloc_percpu(struct per_cpu_pageset
);
4965 for_each_possible_cpu(cpu
)
4966 zone_pageset_init(zone
, cpu
);
4970 * Allocate per cpu pagesets and initialize them.
4971 * Before this call only boot pagesets were available.
4973 void __init
setup_per_cpu_pageset(void)
4977 for_each_populated_zone(zone
)
4978 setup_zone_pageset(zone
);
4981 static noinline __init_refok
4982 int zone_wait_table_init(struct zone
*zone
, unsigned long zone_size_pages
)
4988 * The per-page waitqueue mechanism uses hashed waitqueues
4991 zone
->wait_table_hash_nr_entries
=
4992 wait_table_hash_nr_entries(zone_size_pages
);
4993 zone
->wait_table_bits
=
4994 wait_table_bits(zone
->wait_table_hash_nr_entries
);
4995 alloc_size
= zone
->wait_table_hash_nr_entries
4996 * sizeof(wait_queue_head_t
);
4998 if (!slab_is_available()) {
4999 zone
->wait_table
= (wait_queue_head_t
*)
5000 memblock_virt_alloc_node_nopanic(
5001 alloc_size
, zone
->zone_pgdat
->node_id
);
5004 * This case means that a zone whose size was 0 gets new memory
5005 * via memory hot-add.
5006 * But it may be the case that a new node was hot-added. In
5007 * this case vmalloc() will not be able to use this new node's
5008 * memory - this wait_table must be initialized to use this new
5009 * node itself as well.
5010 * To use this new node's memory, further consideration will be
5013 zone
->wait_table
= vmalloc(alloc_size
);
5015 if (!zone
->wait_table
)
5018 for (i
= 0; i
< zone
->wait_table_hash_nr_entries
; ++i
)
5019 init_waitqueue_head(zone
->wait_table
+ i
);
5024 static __meminit
void zone_pcp_init(struct zone
*zone
)
5027 * per cpu subsystem is not up at this point. The following code
5028 * relies on the ability of the linker to provide the
5029 * offset of a (static) per cpu variable into the per cpu area.
5031 zone
->pageset
= &boot_pageset
;
5033 if (populated_zone(zone
))
5034 printk(KERN_DEBUG
" %s zone: %lu pages, LIFO batch:%u\n",
5035 zone
->name
, zone
->present_pages
,
5036 zone_batchsize(zone
));
5039 int __meminit
init_currently_empty_zone(struct zone
*zone
,
5040 unsigned long zone_start_pfn
,
5043 struct pglist_data
*pgdat
= zone
->zone_pgdat
;
5045 ret
= zone_wait_table_init(zone
, size
);
5048 pgdat
->nr_zones
= zone_idx(zone
) + 1;
5050 zone
->zone_start_pfn
= zone_start_pfn
;
5052 mminit_dprintk(MMINIT_TRACE
, "memmap_init",
5053 "Initialising map node %d zone %lu pfns %lu -> %lu\n",
5055 (unsigned long)zone_idx(zone
),
5056 zone_start_pfn
, (zone_start_pfn
+ size
));
5058 zone_init_free_lists(zone
);
5063 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
5064 #ifndef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
5067 * Required by SPARSEMEM. Given a PFN, return what node the PFN is on.
5069 int __meminit
__early_pfn_to_nid(unsigned long pfn
,
5070 struct mminit_pfnnid_cache
*state
)
5072 unsigned long start_pfn
, end_pfn
;
5075 if (state
->last_start
<= pfn
&& pfn
< state
->last_end
)
5076 return state
->last_nid
;
5078 nid
= memblock_search_pfn_nid(pfn
, &start_pfn
, &end_pfn
);
5080 state
->last_start
= start_pfn
;
5081 state
->last_end
= end_pfn
;
5082 state
->last_nid
= nid
;
5087 #endif /* CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID */
5090 * free_bootmem_with_active_regions - Call memblock_free_early_nid for each active range
5091 * @nid: The node to free memory on. If MAX_NUMNODES, all nodes are freed.
5092 * @max_low_pfn: The highest PFN that will be passed to memblock_free_early_nid
5094 * If an architecture guarantees that all ranges registered contain no holes
5095 * and may be freed, this this function may be used instead of calling
5096 * memblock_free_early_nid() manually.
5098 void __init
free_bootmem_with_active_regions(int nid
, unsigned long max_low_pfn
)
5100 unsigned long start_pfn
, end_pfn
;
5103 for_each_mem_pfn_range(i
, nid
, &start_pfn
, &end_pfn
, &this_nid
) {
5104 start_pfn
= min(start_pfn
, max_low_pfn
);
5105 end_pfn
= min(end_pfn
, max_low_pfn
);
5107 if (start_pfn
< end_pfn
)
5108 memblock_free_early_nid(PFN_PHYS(start_pfn
),
5109 (end_pfn
- start_pfn
) << PAGE_SHIFT
,
5115 * sparse_memory_present_with_active_regions - Call memory_present for each active range
5116 * @nid: The node to call memory_present for. If MAX_NUMNODES, all nodes will be used.
5118 * If an architecture guarantees that all ranges registered contain no holes and may
5119 * be freed, this function may be used instead of calling memory_present() manually.
5121 void __init
sparse_memory_present_with_active_regions(int nid
)
5123 unsigned long start_pfn
, end_pfn
;
5126 for_each_mem_pfn_range(i
, nid
, &start_pfn
, &end_pfn
, &this_nid
)
5127 memory_present(this_nid
, start_pfn
, end_pfn
);
5131 * get_pfn_range_for_nid - Return the start and end page frames for a node
5132 * @nid: The nid to return the range for. If MAX_NUMNODES, the min and max PFN are returned.
5133 * @start_pfn: Passed by reference. On return, it will have the node start_pfn.
5134 * @end_pfn: Passed by reference. On return, it will have the node end_pfn.
5136 * It returns the start and end page frame of a node based on information
5137 * provided by memblock_set_node(). If called for a node
5138 * with no available memory, a warning is printed and the start and end
5141 void __meminit
get_pfn_range_for_nid(unsigned int nid
,
5142 unsigned long *start_pfn
, unsigned long *end_pfn
)
5144 unsigned long this_start_pfn
, this_end_pfn
;
5150 for_each_mem_pfn_range(i
, nid
, &this_start_pfn
, &this_end_pfn
, NULL
) {
5151 *start_pfn
= min(*start_pfn
, this_start_pfn
);
5152 *end_pfn
= max(*end_pfn
, this_end_pfn
);
5155 if (*start_pfn
== -1UL)
5160 * This finds a zone that can be used for ZONE_MOVABLE pages. The
5161 * assumption is made that zones within a node are ordered in monotonic
5162 * increasing memory addresses so that the "highest" populated zone is used
5164 static void __init
find_usable_zone_for_movable(void)
5167 for (zone_index
= MAX_NR_ZONES
- 1; zone_index
>= 0; zone_index
--) {
5168 if (zone_index
== ZONE_MOVABLE
)
5171 if (arch_zone_highest_possible_pfn
[zone_index
] >
5172 arch_zone_lowest_possible_pfn
[zone_index
])
5176 VM_BUG_ON(zone_index
== -1);
5177 movable_zone
= zone_index
;
5181 * The zone ranges provided by the architecture do not include ZONE_MOVABLE
5182 * because it is sized independent of architecture. Unlike the other zones,
5183 * the starting point for ZONE_MOVABLE is not fixed. It may be different
5184 * in each node depending on the size of each node and how evenly kernelcore
5185 * is distributed. This helper function adjusts the zone ranges
5186 * provided by the architecture for a given node by using the end of the
5187 * highest usable zone for ZONE_MOVABLE. This preserves the assumption that
5188 * zones within a node are in order of monotonic increases memory addresses
5190 static void __meminit
adjust_zone_range_for_zone_movable(int nid
,
5191 unsigned long zone_type
,
5192 unsigned long node_start_pfn
,
5193 unsigned long node_end_pfn
,
5194 unsigned long *zone_start_pfn
,
5195 unsigned long *zone_end_pfn
)
5197 /* Only adjust if ZONE_MOVABLE is on this node */
5198 if (zone_movable_pfn
[nid
]) {
5199 /* Size ZONE_MOVABLE */
5200 if (zone_type
== ZONE_MOVABLE
) {
5201 *zone_start_pfn
= zone_movable_pfn
[nid
];
5202 *zone_end_pfn
= min(node_end_pfn
,
5203 arch_zone_highest_possible_pfn
[movable_zone
]);
5205 /* Check if this whole range is within ZONE_MOVABLE */
5206 } else if (*zone_start_pfn
>= zone_movable_pfn
[nid
])
5207 *zone_start_pfn
= *zone_end_pfn
;
5212 * Return the number of pages a zone spans in a node, including holes
5213 * present_pages = zone_spanned_pages_in_node() - zone_absent_pages_in_node()
5215 static unsigned long __meminit
zone_spanned_pages_in_node(int nid
,
5216 unsigned long zone_type
,
5217 unsigned long node_start_pfn
,
5218 unsigned long node_end_pfn
,
5219 unsigned long *zone_start_pfn
,
5220 unsigned long *zone_end_pfn
,
5221 unsigned long *ignored
)
5223 /* When hotadd a new node from cpu_up(), the node should be empty */
5224 if (!node_start_pfn
&& !node_end_pfn
)
5227 /* Get the start and end of the zone */
5228 *zone_start_pfn
= arch_zone_lowest_possible_pfn
[zone_type
];
5229 *zone_end_pfn
= arch_zone_highest_possible_pfn
[zone_type
];
5230 adjust_zone_range_for_zone_movable(nid
, zone_type
,
5231 node_start_pfn
, node_end_pfn
,
5232 zone_start_pfn
, zone_end_pfn
);
5234 /* Check that this node has pages within the zone's required range */
5235 if (*zone_end_pfn
< node_start_pfn
|| *zone_start_pfn
> node_end_pfn
)
5238 /* Move the zone boundaries inside the node if necessary */
5239 *zone_end_pfn
= min(*zone_end_pfn
, node_end_pfn
);
5240 *zone_start_pfn
= max(*zone_start_pfn
, node_start_pfn
);
5242 /* Return the spanned pages */
5243 return *zone_end_pfn
- *zone_start_pfn
;
5247 * Return the number of holes in a range on a node. If nid is MAX_NUMNODES,
5248 * then all holes in the requested range will be accounted for.
5250 unsigned long __meminit
__absent_pages_in_range(int nid
,
5251 unsigned long range_start_pfn
,
5252 unsigned long range_end_pfn
)
5254 unsigned long nr_absent
= range_end_pfn
- range_start_pfn
;
5255 unsigned long start_pfn
, end_pfn
;
5258 for_each_mem_pfn_range(i
, nid
, &start_pfn
, &end_pfn
, NULL
) {
5259 start_pfn
= clamp(start_pfn
, range_start_pfn
, range_end_pfn
);
5260 end_pfn
= clamp(end_pfn
, range_start_pfn
, range_end_pfn
);
5261 nr_absent
-= end_pfn
- start_pfn
;
5267 * absent_pages_in_range - Return number of page frames in holes within a range
5268 * @start_pfn: The start PFN to start searching for holes
5269 * @end_pfn: The end PFN to stop searching for holes
5271 * It returns the number of pages frames in memory holes within a range.
5273 unsigned long __init
absent_pages_in_range(unsigned long start_pfn
,
5274 unsigned long end_pfn
)
5276 return __absent_pages_in_range(MAX_NUMNODES
, start_pfn
, end_pfn
);
5279 /* Return the number of page frames in holes in a zone on a node */
5280 static unsigned long __meminit
zone_absent_pages_in_node(int nid
,
5281 unsigned long zone_type
,
5282 unsigned long node_start_pfn
,
5283 unsigned long node_end_pfn
,
5284 unsigned long *ignored
)
5286 unsigned long zone_low
= arch_zone_lowest_possible_pfn
[zone_type
];
5287 unsigned long zone_high
= arch_zone_highest_possible_pfn
[zone_type
];
5288 unsigned long zone_start_pfn
, zone_end_pfn
;
5289 unsigned long nr_absent
;
5291 /* When hotadd a new node from cpu_up(), the node should be empty */
5292 if (!node_start_pfn
&& !node_end_pfn
)
5295 zone_start_pfn
= clamp(node_start_pfn
, zone_low
, zone_high
);
5296 zone_end_pfn
= clamp(node_end_pfn
, zone_low
, zone_high
);
5298 adjust_zone_range_for_zone_movable(nid
, zone_type
,
5299 node_start_pfn
, node_end_pfn
,
5300 &zone_start_pfn
, &zone_end_pfn
);
5301 nr_absent
= __absent_pages_in_range(nid
, zone_start_pfn
, zone_end_pfn
);
5304 * ZONE_MOVABLE handling.
5305 * Treat pages to be ZONE_MOVABLE in ZONE_NORMAL as absent pages
5308 if (zone_movable_pfn
[nid
]) {
5309 if (mirrored_kernelcore
) {
5310 unsigned long start_pfn
, end_pfn
;
5311 struct memblock_region
*r
;
5313 for_each_memblock(memory
, r
) {
5314 start_pfn
= clamp(memblock_region_memory_base_pfn(r
),
5315 zone_start_pfn
, zone_end_pfn
);
5316 end_pfn
= clamp(memblock_region_memory_end_pfn(r
),
5317 zone_start_pfn
, zone_end_pfn
);
5319 if (zone_type
== ZONE_MOVABLE
&&
5320 memblock_is_mirror(r
))
5321 nr_absent
+= end_pfn
- start_pfn
;
5323 if (zone_type
== ZONE_NORMAL
&&
5324 !memblock_is_mirror(r
))
5325 nr_absent
+= end_pfn
- start_pfn
;
5328 if (zone_type
== ZONE_NORMAL
)
5329 nr_absent
+= node_end_pfn
- zone_movable_pfn
[nid
];
5336 #else /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
5337 static inline unsigned long __meminit
zone_spanned_pages_in_node(int nid
,
5338 unsigned long zone_type
,
5339 unsigned long node_start_pfn
,
5340 unsigned long node_end_pfn
,
5341 unsigned long *zone_start_pfn
,
5342 unsigned long *zone_end_pfn
,
5343 unsigned long *zones_size
)
5347 *zone_start_pfn
= node_start_pfn
;
5348 for (zone
= 0; zone
< zone_type
; zone
++)
5349 *zone_start_pfn
+= zones_size
[zone
];
5351 *zone_end_pfn
= *zone_start_pfn
+ zones_size
[zone_type
];
5353 return zones_size
[zone_type
];
5356 static inline unsigned long __meminit
zone_absent_pages_in_node(int nid
,
5357 unsigned long zone_type
,
5358 unsigned long node_start_pfn
,
5359 unsigned long node_end_pfn
,
5360 unsigned long *zholes_size
)
5365 return zholes_size
[zone_type
];
5368 #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
5370 static void __meminit
calculate_node_totalpages(struct pglist_data
*pgdat
,
5371 unsigned long node_start_pfn
,
5372 unsigned long node_end_pfn
,
5373 unsigned long *zones_size
,
5374 unsigned long *zholes_size
)
5376 unsigned long realtotalpages
= 0, totalpages
= 0;
5379 for (i
= 0; i
< MAX_NR_ZONES
; i
++) {
5380 struct zone
*zone
= pgdat
->node_zones
+ i
;
5381 unsigned long zone_start_pfn
, zone_end_pfn
;
5382 unsigned long size
, real_size
;
5384 size
= zone_spanned_pages_in_node(pgdat
->node_id
, i
,
5390 real_size
= size
- zone_absent_pages_in_node(pgdat
->node_id
, i
,
5391 node_start_pfn
, node_end_pfn
,
5394 zone
->zone_start_pfn
= zone_start_pfn
;
5396 zone
->zone_start_pfn
= 0;
5397 zone
->spanned_pages
= size
;
5398 zone
->present_pages
= real_size
;
5401 realtotalpages
+= real_size
;
5404 pgdat
->node_spanned_pages
= totalpages
;
5405 pgdat
->node_present_pages
= realtotalpages
;
5406 printk(KERN_DEBUG
"On node %d totalpages: %lu\n", pgdat
->node_id
,
5410 #ifndef CONFIG_SPARSEMEM
5412 * Calculate the size of the zone->blockflags rounded to an unsigned long
5413 * Start by making sure zonesize is a multiple of pageblock_order by rounding
5414 * up. Then use 1 NR_PAGEBLOCK_BITS worth of bits per pageblock, finally
5415 * round what is now in bits to nearest long in bits, then return it in
5418 static unsigned long __init
usemap_size(unsigned long zone_start_pfn
, unsigned long zonesize
)
5420 unsigned long usemapsize
;
5422 zonesize
+= zone_start_pfn
& (pageblock_nr_pages
-1);
5423 usemapsize
= roundup(zonesize
, pageblock_nr_pages
);
5424 usemapsize
= usemapsize
>> pageblock_order
;
5425 usemapsize
*= NR_PAGEBLOCK_BITS
;
5426 usemapsize
= roundup(usemapsize
, 8 * sizeof(unsigned long));
5428 return usemapsize
/ 8;
5431 static void __init
setup_usemap(struct pglist_data
*pgdat
,
5433 unsigned long zone_start_pfn
,
5434 unsigned long zonesize
)
5436 unsigned long usemapsize
= usemap_size(zone_start_pfn
, zonesize
);
5437 zone
->pageblock_flags
= NULL
;
5439 zone
->pageblock_flags
=
5440 memblock_virt_alloc_node_nopanic(usemapsize
,
5444 static inline void setup_usemap(struct pglist_data
*pgdat
, struct zone
*zone
,
5445 unsigned long zone_start_pfn
, unsigned long zonesize
) {}
5446 #endif /* CONFIG_SPARSEMEM */
5448 #ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
5450 /* Initialise the number of pages represented by NR_PAGEBLOCK_BITS */
5451 void __paginginit
set_pageblock_order(void)
5455 /* Check that pageblock_nr_pages has not already been setup */
5456 if (pageblock_order
)
5459 if (HPAGE_SHIFT
> PAGE_SHIFT
)
5460 order
= HUGETLB_PAGE_ORDER
;
5462 order
= MAX_ORDER
- 1;
5465 * Assume the largest contiguous order of interest is a huge page.
5466 * This value may be variable depending on boot parameters on IA64 and
5469 pageblock_order
= order
;
5471 #else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
5474 * When CONFIG_HUGETLB_PAGE_SIZE_VARIABLE is not set, set_pageblock_order()
5475 * is unused as pageblock_order is set at compile-time. See
5476 * include/linux/pageblock-flags.h for the values of pageblock_order based on
5479 void __paginginit
set_pageblock_order(void)
5483 #endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
5485 static unsigned long __paginginit
calc_memmap_size(unsigned long spanned_pages
,
5486 unsigned long present_pages
)
5488 unsigned long pages
= spanned_pages
;
5491 * Provide a more accurate estimation if there are holes within
5492 * the zone and SPARSEMEM is in use. If there are holes within the
5493 * zone, each populated memory region may cost us one or two extra
5494 * memmap pages due to alignment because memmap pages for each
5495 * populated regions may not naturally algined on page boundary.
5496 * So the (present_pages >> 4) heuristic is a tradeoff for that.
5498 if (spanned_pages
> present_pages
+ (present_pages
>> 4) &&
5499 IS_ENABLED(CONFIG_SPARSEMEM
))
5500 pages
= present_pages
;
5502 return PAGE_ALIGN(pages
* sizeof(struct page
)) >> PAGE_SHIFT
;
5506 * Set up the zone data structures:
5507 * - mark all pages reserved
5508 * - mark all memory queues empty
5509 * - clear the memory bitmaps
5511 * NOTE: pgdat should get zeroed by caller.
5513 static void __paginginit
free_area_init_core(struct pglist_data
*pgdat
)
5516 int nid
= pgdat
->node_id
;
5519 pgdat_resize_init(pgdat
);
5520 #ifdef CONFIG_NUMA_BALANCING
5521 spin_lock_init(&pgdat
->numabalancing_migrate_lock
);
5522 pgdat
->numabalancing_migrate_nr_pages
= 0;
5523 pgdat
->numabalancing_migrate_next_window
= jiffies
;
5525 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
5526 spin_lock_init(&pgdat
->split_queue_lock
);
5527 INIT_LIST_HEAD(&pgdat
->split_queue
);
5528 pgdat
->split_queue_len
= 0;
5530 init_waitqueue_head(&pgdat
->kswapd_wait
);
5531 init_waitqueue_head(&pgdat
->pfmemalloc_wait
);
5532 #ifdef CONFIG_COMPACTION
5533 init_waitqueue_head(&pgdat
->kcompactd_wait
);
5535 pgdat_page_ext_init(pgdat
);
5537 for (j
= 0; j
< MAX_NR_ZONES
; j
++) {
5538 struct zone
*zone
= pgdat
->node_zones
+ j
;
5539 unsigned long size
, realsize
, freesize
, memmap_pages
;
5540 unsigned long zone_start_pfn
= zone
->zone_start_pfn
;
5542 size
= zone
->spanned_pages
;
5543 realsize
= freesize
= zone
->present_pages
;
5546 * Adjust freesize so that it accounts for how much memory
5547 * is used by this zone for memmap. This affects the watermark
5548 * and per-cpu initialisations
5550 memmap_pages
= calc_memmap_size(size
, realsize
);
5551 if (!is_highmem_idx(j
)) {
5552 if (freesize
>= memmap_pages
) {
5553 freesize
-= memmap_pages
;
5556 " %s zone: %lu pages used for memmap\n",
5557 zone_names
[j
], memmap_pages
);
5559 pr_warn(" %s zone: %lu pages exceeds freesize %lu\n",
5560 zone_names
[j
], memmap_pages
, freesize
);
5563 /* Account for reserved pages */
5564 if (j
== 0 && freesize
> dma_reserve
) {
5565 freesize
-= dma_reserve
;
5566 printk(KERN_DEBUG
" %s zone: %lu pages reserved\n",
5567 zone_names
[0], dma_reserve
);
5570 if (!is_highmem_idx(j
))
5571 nr_kernel_pages
+= freesize
;
5572 /* Charge for highmem memmap if there are enough kernel pages */
5573 else if (nr_kernel_pages
> memmap_pages
* 2)
5574 nr_kernel_pages
-= memmap_pages
;
5575 nr_all_pages
+= freesize
;
5578 * Set an approximate value for lowmem here, it will be adjusted
5579 * when the bootmem allocator frees pages into the buddy system.
5580 * And all highmem pages will be managed by the buddy system.
5582 zone
->managed_pages
= is_highmem_idx(j
) ? realsize
: freesize
;
5585 zone
->min_unmapped_pages
= (freesize
*sysctl_min_unmapped_ratio
)
5587 zone
->min_slab_pages
= (freesize
* sysctl_min_slab_ratio
) / 100;
5589 zone
->name
= zone_names
[j
];
5590 spin_lock_init(&zone
->lock
);
5591 spin_lock_init(&zone
->lru_lock
);
5592 zone_seqlock_init(zone
);
5593 zone
->zone_pgdat
= pgdat
;
5594 zone_pcp_init(zone
);
5596 /* For bootup, initialized properly in watermark setup */
5597 mod_zone_page_state(zone
, NR_ALLOC_BATCH
, zone
->managed_pages
);
5599 lruvec_init(&zone
->lruvec
);
5603 set_pageblock_order();
5604 setup_usemap(pgdat
, zone
, zone_start_pfn
, size
);
5605 ret
= init_currently_empty_zone(zone
, zone_start_pfn
, size
);
5607 memmap_init(size
, nid
, j
, zone_start_pfn
);
5611 static void __init_refok
alloc_node_mem_map(struct pglist_data
*pgdat
)
5613 unsigned long __maybe_unused start
= 0;
5614 unsigned long __maybe_unused offset
= 0;
5616 /* Skip empty nodes */
5617 if (!pgdat
->node_spanned_pages
)
5620 #ifdef CONFIG_FLAT_NODE_MEM_MAP
5621 start
= pgdat
->node_start_pfn
& ~(MAX_ORDER_NR_PAGES
- 1);
5622 offset
= pgdat
->node_start_pfn
- start
;
5623 /* ia64 gets its own node_mem_map, before this, without bootmem */
5624 if (!pgdat
->node_mem_map
) {
5625 unsigned long size
, end
;
5629 * The zone's endpoints aren't required to be MAX_ORDER
5630 * aligned but the node_mem_map endpoints must be in order
5631 * for the buddy allocator to function correctly.
5633 end
= pgdat_end_pfn(pgdat
);
5634 end
= ALIGN(end
, MAX_ORDER_NR_PAGES
);
5635 size
= (end
- start
) * sizeof(struct page
);
5636 map
= alloc_remap(pgdat
->node_id
, size
);
5638 map
= memblock_virt_alloc_node_nopanic(size
,
5640 pgdat
->node_mem_map
= map
+ offset
;
5642 #ifndef CONFIG_NEED_MULTIPLE_NODES
5644 * With no DISCONTIG, the global mem_map is just set as node 0's
5646 if (pgdat
== NODE_DATA(0)) {
5647 mem_map
= NODE_DATA(0)->node_mem_map
;
5648 #if defined(CONFIG_HAVE_MEMBLOCK_NODE_MAP) || defined(CONFIG_FLATMEM)
5649 if (page_to_pfn(mem_map
) != pgdat
->node_start_pfn
)
5651 #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
5654 #endif /* CONFIG_FLAT_NODE_MEM_MAP */
5657 void __paginginit
free_area_init_node(int nid
, unsigned long *zones_size
,
5658 unsigned long node_start_pfn
, unsigned long *zholes_size
)
5660 pg_data_t
*pgdat
= NODE_DATA(nid
);
5661 unsigned long start_pfn
= 0;
5662 unsigned long end_pfn
= 0;
5664 /* pg_data_t should be reset to zero when it's allocated */
5665 WARN_ON(pgdat
->nr_zones
|| pgdat
->classzone_idx
);
5667 reset_deferred_meminit(pgdat
);
5668 pgdat
->node_id
= nid
;
5669 pgdat
->node_start_pfn
= node_start_pfn
;
5670 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
5671 get_pfn_range_for_nid(nid
, &start_pfn
, &end_pfn
);
5672 pr_info("Initmem setup node %d [mem %#018Lx-%#018Lx]\n", nid
,
5673 (u64
)start_pfn
<< PAGE_SHIFT
,
5674 end_pfn
? ((u64
)end_pfn
<< PAGE_SHIFT
) - 1 : 0);
5676 start_pfn
= node_start_pfn
;
5678 calculate_node_totalpages(pgdat
, start_pfn
, end_pfn
,
5679 zones_size
, zholes_size
);
5681 alloc_node_mem_map(pgdat
);
5682 #ifdef CONFIG_FLAT_NODE_MEM_MAP
5683 printk(KERN_DEBUG
"free_area_init_node: node %d, pgdat %08lx, node_mem_map %08lx\n",
5684 nid
, (unsigned long)pgdat
,
5685 (unsigned long)pgdat
->node_mem_map
);
5688 free_area_init_core(pgdat
);
5691 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
5693 #if MAX_NUMNODES > 1
5695 * Figure out the number of possible node ids.
5697 void __init
setup_nr_node_ids(void)
5699 unsigned int highest
;
5701 highest
= find_last_bit(node_possible_map
.bits
, MAX_NUMNODES
);
5702 nr_node_ids
= highest
+ 1;
5707 * node_map_pfn_alignment - determine the maximum internode alignment
5709 * This function should be called after node map is populated and sorted.
5710 * It calculates the maximum power of two alignment which can distinguish
5713 * For example, if all nodes are 1GiB and aligned to 1GiB, the return value
5714 * would indicate 1GiB alignment with (1 << (30 - PAGE_SHIFT)). If the
5715 * nodes are shifted by 256MiB, 256MiB. Note that if only the last node is
5716 * shifted, 1GiB is enough and this function will indicate so.
5718 * This is used to test whether pfn -> nid mapping of the chosen memory
5719 * model has fine enough granularity to avoid incorrect mapping for the
5720 * populated node map.
5722 * Returns the determined alignment in pfn's. 0 if there is no alignment
5723 * requirement (single node).
5725 unsigned long __init
node_map_pfn_alignment(void)
5727 unsigned long accl_mask
= 0, last_end
= 0;
5728 unsigned long start
, end
, mask
;
5732 for_each_mem_pfn_range(i
, MAX_NUMNODES
, &start
, &end
, &nid
) {
5733 if (!start
|| last_nid
< 0 || last_nid
== nid
) {
5740 * Start with a mask granular enough to pin-point to the
5741 * start pfn and tick off bits one-by-one until it becomes
5742 * too coarse to separate the current node from the last.
5744 mask
= ~((1 << __ffs(start
)) - 1);
5745 while (mask
&& last_end
<= (start
& (mask
<< 1)))
5748 /* accumulate all internode masks */
5752 /* convert mask to number of pages */
5753 return ~accl_mask
+ 1;
5756 /* Find the lowest pfn for a node */
5757 static unsigned long __init
find_min_pfn_for_node(int nid
)
5759 unsigned long min_pfn
= ULONG_MAX
;
5760 unsigned long start_pfn
;
5763 for_each_mem_pfn_range(i
, nid
, &start_pfn
, NULL
, NULL
)
5764 min_pfn
= min(min_pfn
, start_pfn
);
5766 if (min_pfn
== ULONG_MAX
) {
5767 pr_warn("Could not find start_pfn for node %d\n", nid
);
5775 * find_min_pfn_with_active_regions - Find the minimum PFN registered
5777 * It returns the minimum PFN based on information provided via
5778 * memblock_set_node().
5780 unsigned long __init
find_min_pfn_with_active_regions(void)
5782 return find_min_pfn_for_node(MAX_NUMNODES
);
5786 * early_calculate_totalpages()
5787 * Sum pages in active regions for movable zone.
5788 * Populate N_MEMORY for calculating usable_nodes.
5790 static unsigned long __init
early_calculate_totalpages(void)
5792 unsigned long totalpages
= 0;
5793 unsigned long start_pfn
, end_pfn
;
5796 for_each_mem_pfn_range(i
, MAX_NUMNODES
, &start_pfn
, &end_pfn
, &nid
) {
5797 unsigned long pages
= end_pfn
- start_pfn
;
5799 totalpages
+= pages
;
5801 node_set_state(nid
, N_MEMORY
);
5807 * Find the PFN the Movable zone begins in each node. Kernel memory
5808 * is spread evenly between nodes as long as the nodes have enough
5809 * memory. When they don't, some nodes will have more kernelcore than
5812 static void __init
find_zone_movable_pfns_for_nodes(void)
5815 unsigned long usable_startpfn
;
5816 unsigned long kernelcore_node
, kernelcore_remaining
;
5817 /* save the state before borrow the nodemask */
5818 nodemask_t saved_node_state
= node_states
[N_MEMORY
];
5819 unsigned long totalpages
= early_calculate_totalpages();
5820 int usable_nodes
= nodes_weight(node_states
[N_MEMORY
]);
5821 struct memblock_region
*r
;
5823 /* Need to find movable_zone earlier when movable_node is specified. */
5824 find_usable_zone_for_movable();
5827 * If movable_node is specified, ignore kernelcore and movablecore
5830 if (movable_node_is_enabled()) {
5831 for_each_memblock(memory
, r
) {
5832 if (!memblock_is_hotpluggable(r
))
5837 usable_startpfn
= PFN_DOWN(r
->base
);
5838 zone_movable_pfn
[nid
] = zone_movable_pfn
[nid
] ?
5839 min(usable_startpfn
, zone_movable_pfn
[nid
]) :
5847 * If kernelcore=mirror is specified, ignore movablecore option
5849 if (mirrored_kernelcore
) {
5850 bool mem_below_4gb_not_mirrored
= false;
5852 for_each_memblock(memory
, r
) {
5853 if (memblock_is_mirror(r
))
5858 usable_startpfn
= memblock_region_memory_base_pfn(r
);
5860 if (usable_startpfn
< 0x100000) {
5861 mem_below_4gb_not_mirrored
= true;
5865 zone_movable_pfn
[nid
] = zone_movable_pfn
[nid
] ?
5866 min(usable_startpfn
, zone_movable_pfn
[nid
]) :
5870 if (mem_below_4gb_not_mirrored
)
5871 pr_warn("This configuration results in unmirrored kernel memory.");
5877 * If movablecore=nn[KMG] was specified, calculate what size of
5878 * kernelcore that corresponds so that memory usable for
5879 * any allocation type is evenly spread. If both kernelcore
5880 * and movablecore are specified, then the value of kernelcore
5881 * will be used for required_kernelcore if it's greater than
5882 * what movablecore would have allowed.
5884 if (required_movablecore
) {
5885 unsigned long corepages
;
5888 * Round-up so that ZONE_MOVABLE is at least as large as what
5889 * was requested by the user
5891 required_movablecore
=
5892 roundup(required_movablecore
, MAX_ORDER_NR_PAGES
);
5893 required_movablecore
= min(totalpages
, required_movablecore
);
5894 corepages
= totalpages
- required_movablecore
;
5896 required_kernelcore
= max(required_kernelcore
, corepages
);
5900 * If kernelcore was not specified or kernelcore size is larger
5901 * than totalpages, there is no ZONE_MOVABLE.
5903 if (!required_kernelcore
|| required_kernelcore
>= totalpages
)
5906 /* usable_startpfn is the lowest possible pfn ZONE_MOVABLE can be at */
5907 usable_startpfn
= arch_zone_lowest_possible_pfn
[movable_zone
];
5910 /* Spread kernelcore memory as evenly as possible throughout nodes */
5911 kernelcore_node
= required_kernelcore
/ usable_nodes
;
5912 for_each_node_state(nid
, N_MEMORY
) {
5913 unsigned long start_pfn
, end_pfn
;
5916 * Recalculate kernelcore_node if the division per node
5917 * now exceeds what is necessary to satisfy the requested
5918 * amount of memory for the kernel
5920 if (required_kernelcore
< kernelcore_node
)
5921 kernelcore_node
= required_kernelcore
/ usable_nodes
;
5924 * As the map is walked, we track how much memory is usable
5925 * by the kernel using kernelcore_remaining. When it is
5926 * 0, the rest of the node is usable by ZONE_MOVABLE
5928 kernelcore_remaining
= kernelcore_node
;
5930 /* Go through each range of PFNs within this node */
5931 for_each_mem_pfn_range(i
, nid
, &start_pfn
, &end_pfn
, NULL
) {
5932 unsigned long size_pages
;
5934 start_pfn
= max(start_pfn
, zone_movable_pfn
[nid
]);
5935 if (start_pfn
>= end_pfn
)
5938 /* Account for what is only usable for kernelcore */
5939 if (start_pfn
< usable_startpfn
) {
5940 unsigned long kernel_pages
;
5941 kernel_pages
= min(end_pfn
, usable_startpfn
)
5944 kernelcore_remaining
-= min(kernel_pages
,
5945 kernelcore_remaining
);
5946 required_kernelcore
-= min(kernel_pages
,
5947 required_kernelcore
);
5949 /* Continue if range is now fully accounted */
5950 if (end_pfn
<= usable_startpfn
) {
5953 * Push zone_movable_pfn to the end so
5954 * that if we have to rebalance
5955 * kernelcore across nodes, we will
5956 * not double account here
5958 zone_movable_pfn
[nid
] = end_pfn
;
5961 start_pfn
= usable_startpfn
;
5965 * The usable PFN range for ZONE_MOVABLE is from
5966 * start_pfn->end_pfn. Calculate size_pages as the
5967 * number of pages used as kernelcore
5969 size_pages
= end_pfn
- start_pfn
;
5970 if (size_pages
> kernelcore_remaining
)
5971 size_pages
= kernelcore_remaining
;
5972 zone_movable_pfn
[nid
] = start_pfn
+ size_pages
;
5975 * Some kernelcore has been met, update counts and
5976 * break if the kernelcore for this node has been
5979 required_kernelcore
-= min(required_kernelcore
,
5981 kernelcore_remaining
-= size_pages
;
5982 if (!kernelcore_remaining
)
5988 * If there is still required_kernelcore, we do another pass with one
5989 * less node in the count. This will push zone_movable_pfn[nid] further
5990 * along on the nodes that still have memory until kernelcore is
5994 if (usable_nodes
&& required_kernelcore
> usable_nodes
)
5998 /* Align start of ZONE_MOVABLE on all nids to MAX_ORDER_NR_PAGES */
5999 for (nid
= 0; nid
< MAX_NUMNODES
; nid
++)
6000 zone_movable_pfn
[nid
] =
6001 roundup(zone_movable_pfn
[nid
], MAX_ORDER_NR_PAGES
);
6004 /* restore the node_state */
6005 node_states
[N_MEMORY
] = saved_node_state
;
6008 /* Any regular or high memory on that node ? */
6009 static void check_for_memory(pg_data_t
*pgdat
, int nid
)
6011 enum zone_type zone_type
;
6013 if (N_MEMORY
== N_NORMAL_MEMORY
)
6016 for (zone_type
= 0; zone_type
<= ZONE_MOVABLE
- 1; zone_type
++) {
6017 struct zone
*zone
= &pgdat
->node_zones
[zone_type
];
6018 if (populated_zone(zone
)) {
6019 node_set_state(nid
, N_HIGH_MEMORY
);
6020 if (N_NORMAL_MEMORY
!= N_HIGH_MEMORY
&&
6021 zone_type
<= ZONE_NORMAL
)
6022 node_set_state(nid
, N_NORMAL_MEMORY
);
6029 * free_area_init_nodes - Initialise all pg_data_t and zone data
6030 * @max_zone_pfn: an array of max PFNs for each zone
6032 * This will call free_area_init_node() for each active node in the system.
6033 * Using the page ranges provided by memblock_set_node(), the size of each
6034 * zone in each node and their holes is calculated. If the maximum PFN
6035 * between two adjacent zones match, it is assumed that the zone is empty.
6036 * For example, if arch_max_dma_pfn == arch_max_dma32_pfn, it is assumed
6037 * that arch_max_dma32_pfn has no pages. It is also assumed that a zone
6038 * starts where the previous one ended. For example, ZONE_DMA32 starts
6039 * at arch_max_dma_pfn.
6041 void __init
free_area_init_nodes(unsigned long *max_zone_pfn
)
6043 unsigned long start_pfn
, end_pfn
;
6046 /* Record where the zone boundaries are */
6047 memset(arch_zone_lowest_possible_pfn
, 0,
6048 sizeof(arch_zone_lowest_possible_pfn
));
6049 memset(arch_zone_highest_possible_pfn
, 0,
6050 sizeof(arch_zone_highest_possible_pfn
));
6051 arch_zone_lowest_possible_pfn
[0] = find_min_pfn_with_active_regions();
6052 arch_zone_highest_possible_pfn
[0] = max_zone_pfn
[0];
6053 for (i
= 1; i
< MAX_NR_ZONES
; i
++) {
6054 if (i
== ZONE_MOVABLE
)
6056 arch_zone_lowest_possible_pfn
[i
] =
6057 arch_zone_highest_possible_pfn
[i
-1];
6058 arch_zone_highest_possible_pfn
[i
] =
6059 max(max_zone_pfn
[i
], arch_zone_lowest_possible_pfn
[i
]);
6061 arch_zone_lowest_possible_pfn
[ZONE_MOVABLE
] = 0;
6062 arch_zone_highest_possible_pfn
[ZONE_MOVABLE
] = 0;
6064 /* Find the PFNs that ZONE_MOVABLE begins at in each node */
6065 memset(zone_movable_pfn
, 0, sizeof(zone_movable_pfn
));
6066 find_zone_movable_pfns_for_nodes();
6068 /* Print out the zone ranges */
6069 pr_info("Zone ranges:\n");
6070 for (i
= 0; i
< MAX_NR_ZONES
; i
++) {
6071 if (i
== ZONE_MOVABLE
)
6073 pr_info(" %-8s ", zone_names
[i
]);
6074 if (arch_zone_lowest_possible_pfn
[i
] ==
6075 arch_zone_highest_possible_pfn
[i
])
6078 pr_cont("[mem %#018Lx-%#018Lx]\n",
6079 (u64
)arch_zone_lowest_possible_pfn
[i
]
6081 ((u64
)arch_zone_highest_possible_pfn
[i
]
6082 << PAGE_SHIFT
) - 1);
6085 /* Print out the PFNs ZONE_MOVABLE begins at in each node */
6086 pr_info("Movable zone start for each node\n");
6087 for (i
= 0; i
< MAX_NUMNODES
; i
++) {
6088 if (zone_movable_pfn
[i
])
6089 pr_info(" Node %d: %#018Lx\n", i
,
6090 (u64
)zone_movable_pfn
[i
] << PAGE_SHIFT
);
6093 /* Print out the early node map */
6094 pr_info("Early memory node ranges\n");
6095 for_each_mem_pfn_range(i
, MAX_NUMNODES
, &start_pfn
, &end_pfn
, &nid
)
6096 pr_info(" node %3d: [mem %#018Lx-%#018Lx]\n", nid
,
6097 (u64
)start_pfn
<< PAGE_SHIFT
,
6098 ((u64
)end_pfn
<< PAGE_SHIFT
) - 1);
6100 /* Initialise every node */
6101 mminit_verify_pageflags_layout();
6102 setup_nr_node_ids();
6103 for_each_online_node(nid
) {
6104 pg_data_t
*pgdat
= NODE_DATA(nid
);
6105 free_area_init_node(nid
, NULL
,
6106 find_min_pfn_for_node(nid
), NULL
);
6108 /* Any memory on that node */
6109 if (pgdat
->node_present_pages
)
6110 node_set_state(nid
, N_MEMORY
);
6111 check_for_memory(pgdat
, nid
);
6115 static int __init
cmdline_parse_core(char *p
, unsigned long *core
)
6117 unsigned long long coremem
;
6121 coremem
= memparse(p
, &p
);
6122 *core
= coremem
>> PAGE_SHIFT
;
6124 /* Paranoid check that UL is enough for the coremem value */
6125 WARN_ON((coremem
>> PAGE_SHIFT
) > ULONG_MAX
);
6131 * kernelcore=size sets the amount of memory for use for allocations that
6132 * cannot be reclaimed or migrated.
6134 static int __init
cmdline_parse_kernelcore(char *p
)
6136 /* parse kernelcore=mirror */
6137 if (parse_option_str(p
, "mirror")) {
6138 mirrored_kernelcore
= true;
6142 return cmdline_parse_core(p
, &required_kernelcore
);
6146 * movablecore=size sets the amount of memory for use for allocations that
6147 * can be reclaimed or migrated.
6149 static int __init
cmdline_parse_movablecore(char *p
)
6151 return cmdline_parse_core(p
, &required_movablecore
);
6154 early_param("kernelcore", cmdline_parse_kernelcore
);
6155 early_param("movablecore", cmdline_parse_movablecore
);
6157 #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
6159 void adjust_managed_page_count(struct page
*page
, long count
)
6161 spin_lock(&managed_page_count_lock
);
6162 page_zone(page
)->managed_pages
+= count
;
6163 totalram_pages
+= count
;
6164 #ifdef CONFIG_HIGHMEM
6165 if (PageHighMem(page
))
6166 totalhigh_pages
+= count
;
6168 spin_unlock(&managed_page_count_lock
);
6170 EXPORT_SYMBOL(adjust_managed_page_count
);
6172 unsigned long free_reserved_area(void *start
, void *end
, int poison
, char *s
)
6175 unsigned long pages
= 0;
6177 start
= (void *)PAGE_ALIGN((unsigned long)start
);
6178 end
= (void *)((unsigned long)end
& PAGE_MASK
);
6179 for (pos
= start
; pos
< end
; pos
+= PAGE_SIZE
, pages
++) {
6180 if ((unsigned int)poison
<= 0xFF)
6181 memset(pos
, poison
, PAGE_SIZE
);
6182 free_reserved_page(virt_to_page(pos
));
6186 pr_info("Freeing %s memory: %ldK (%p - %p)\n",
6187 s
, pages
<< (PAGE_SHIFT
- 10), start
, end
);
6191 EXPORT_SYMBOL(free_reserved_area
);
6193 #ifdef CONFIG_HIGHMEM
6194 void free_highmem_page(struct page
*page
)
6196 __free_reserved_page(page
);
6198 page_zone(page
)->managed_pages
++;
6204 void __init
mem_init_print_info(const char *str
)
6206 unsigned long physpages
, codesize
, datasize
, rosize
, bss_size
;
6207 unsigned long init_code_size
, init_data_size
;
6209 physpages
= get_num_physpages();
6210 codesize
= _etext
- _stext
;
6211 datasize
= _edata
- _sdata
;
6212 rosize
= __end_rodata
- __start_rodata
;
6213 bss_size
= __bss_stop
- __bss_start
;
6214 init_data_size
= __init_end
- __init_begin
;
6215 init_code_size
= _einittext
- _sinittext
;
6218 * Detect special cases and adjust section sizes accordingly:
6219 * 1) .init.* may be embedded into .data sections
6220 * 2) .init.text.* may be out of [__init_begin, __init_end],
6221 * please refer to arch/tile/kernel/vmlinux.lds.S.
6222 * 3) .rodata.* may be embedded into .text or .data sections.
6224 #define adj_init_size(start, end, size, pos, adj) \
6226 if (start <= pos && pos < end && size > adj) \
6230 adj_init_size(__init_begin
, __init_end
, init_data_size
,
6231 _sinittext
, init_code_size
);
6232 adj_init_size(_stext
, _etext
, codesize
, _sinittext
, init_code_size
);
6233 adj_init_size(_sdata
, _edata
, datasize
, __init_begin
, init_data_size
);
6234 adj_init_size(_stext
, _etext
, codesize
, __start_rodata
, rosize
);
6235 adj_init_size(_sdata
, _edata
, datasize
, __start_rodata
, rosize
);
6237 #undef adj_init_size
6239 pr_info("Memory: %luK/%luK available (%luK kernel code, %luK rwdata, %luK rodata, %luK init, %luK bss, %luK reserved, %luK cma-reserved"
6240 #ifdef CONFIG_HIGHMEM
6244 nr_free_pages() << (PAGE_SHIFT
- 10),
6245 physpages
<< (PAGE_SHIFT
- 10),
6246 codesize
>> 10, datasize
>> 10, rosize
>> 10,
6247 (init_data_size
+ init_code_size
) >> 10, bss_size
>> 10,
6248 (physpages
- totalram_pages
- totalcma_pages
) << (PAGE_SHIFT
- 10),
6249 totalcma_pages
<< (PAGE_SHIFT
- 10),
6250 #ifdef CONFIG_HIGHMEM
6251 totalhigh_pages
<< (PAGE_SHIFT
- 10),
6253 str
? ", " : "", str
? str
: "");
6257 * set_dma_reserve - set the specified number of pages reserved in the first zone
6258 * @new_dma_reserve: The number of pages to mark reserved
6260 * The per-cpu batchsize and zone watermarks are determined by managed_pages.
6261 * In the DMA zone, a significant percentage may be consumed by kernel image
6262 * and other unfreeable allocations which can skew the watermarks badly. This
6263 * function may optionally be used to account for unfreeable pages in the
6264 * first zone (e.g., ZONE_DMA). The effect will be lower watermarks and
6265 * smaller per-cpu batchsize.
6267 void __init
set_dma_reserve(unsigned long new_dma_reserve
)
6269 dma_reserve
= new_dma_reserve
;
6272 void __init
free_area_init(unsigned long *zones_size
)
6274 free_area_init_node(0, zones_size
,
6275 __pa(PAGE_OFFSET
) >> PAGE_SHIFT
, NULL
);
6278 static int page_alloc_cpu_notify(struct notifier_block
*self
,
6279 unsigned long action
, void *hcpu
)
6281 int cpu
= (unsigned long)hcpu
;
6283 if (action
== CPU_DEAD
|| action
== CPU_DEAD_FROZEN
) {
6284 lru_add_drain_cpu(cpu
);
6288 * Spill the event counters of the dead processor
6289 * into the current processors event counters.
6290 * This artificially elevates the count of the current
6293 vm_events_fold_cpu(cpu
);
6296 * Zero the differential counters of the dead processor
6297 * so that the vm statistics are consistent.
6299 * This is only okay since the processor is dead and cannot
6300 * race with what we are doing.
6302 cpu_vm_stats_fold(cpu
);
6307 void __init
page_alloc_init(void)
6309 hotcpu_notifier(page_alloc_cpu_notify
, 0);
6313 * calculate_totalreserve_pages - called when sysctl_lowmem_reserve_ratio
6314 * or min_free_kbytes changes.
6316 static void calculate_totalreserve_pages(void)
6318 struct pglist_data
*pgdat
;
6319 unsigned long reserve_pages
= 0;
6320 enum zone_type i
, j
;
6322 for_each_online_pgdat(pgdat
) {
6323 for (i
= 0; i
< MAX_NR_ZONES
; i
++) {
6324 struct zone
*zone
= pgdat
->node_zones
+ i
;
6327 /* Find valid and maximum lowmem_reserve in the zone */
6328 for (j
= i
; j
< MAX_NR_ZONES
; j
++) {
6329 if (zone
->lowmem_reserve
[j
] > max
)
6330 max
= zone
->lowmem_reserve
[j
];
6333 /* we treat the high watermark as reserved pages. */
6334 max
+= high_wmark_pages(zone
);
6336 if (max
> zone
->managed_pages
)
6337 max
= zone
->managed_pages
;
6339 zone
->totalreserve_pages
= max
;
6341 reserve_pages
+= max
;
6344 totalreserve_pages
= reserve_pages
;
6348 * setup_per_zone_lowmem_reserve - called whenever
6349 * sysctl_lowmem_reserve_ratio changes. Ensures that each zone
6350 * has a correct pages reserved value, so an adequate number of
6351 * pages are left in the zone after a successful __alloc_pages().
6353 static void setup_per_zone_lowmem_reserve(void)
6355 struct pglist_data
*pgdat
;
6356 enum zone_type j
, idx
;
6358 for_each_online_pgdat(pgdat
) {
6359 for (j
= 0; j
< MAX_NR_ZONES
; j
++) {
6360 struct zone
*zone
= pgdat
->node_zones
+ j
;
6361 unsigned long managed_pages
= zone
->managed_pages
;
6363 zone
->lowmem_reserve
[j
] = 0;
6367 struct zone
*lower_zone
;
6371 if (sysctl_lowmem_reserve_ratio
[idx
] < 1)
6372 sysctl_lowmem_reserve_ratio
[idx
] = 1;
6374 lower_zone
= pgdat
->node_zones
+ idx
;
6375 lower_zone
->lowmem_reserve
[j
] = managed_pages
/
6376 sysctl_lowmem_reserve_ratio
[idx
];
6377 managed_pages
+= lower_zone
->managed_pages
;
6382 /* update totalreserve_pages */
6383 calculate_totalreserve_pages();
6386 static void __setup_per_zone_wmarks(void)
6388 unsigned long pages_min
= min_free_kbytes
>> (PAGE_SHIFT
- 10);
6389 unsigned long lowmem_pages
= 0;
6391 unsigned long flags
;
6393 /* Calculate total number of !ZONE_HIGHMEM pages */
6394 for_each_zone(zone
) {
6395 if (!is_highmem(zone
))
6396 lowmem_pages
+= zone
->managed_pages
;
6399 for_each_zone(zone
) {
6402 spin_lock_irqsave(&zone
->lock
, flags
);
6403 tmp
= (u64
)pages_min
* zone
->managed_pages
;
6404 do_div(tmp
, lowmem_pages
);
6405 if (is_highmem(zone
)) {
6407 * __GFP_HIGH and PF_MEMALLOC allocations usually don't
6408 * need highmem pages, so cap pages_min to a small
6411 * The WMARK_HIGH-WMARK_LOW and (WMARK_LOW-WMARK_MIN)
6412 * deltas control asynch page reclaim, and so should
6413 * not be capped for highmem.
6415 unsigned long min_pages
;
6417 min_pages
= zone
->managed_pages
/ 1024;
6418 min_pages
= clamp(min_pages
, SWAP_CLUSTER_MAX
, 128UL);
6419 zone
->watermark
[WMARK_MIN
] = min_pages
;
6422 * If it's a lowmem zone, reserve a number of pages
6423 * proportionate to the zone's size.
6425 zone
->watermark
[WMARK_MIN
] = tmp
;
6429 * Set the kswapd watermarks distance according to the
6430 * scale factor in proportion to available memory, but
6431 * ensure a minimum size on small systems.
6433 tmp
= max_t(u64
, tmp
>> 2,
6434 mult_frac(zone
->managed_pages
,
6435 watermark_scale_factor
, 10000));
6437 zone
->watermark
[WMARK_LOW
] = min_wmark_pages(zone
) + tmp
;
6438 zone
->watermark
[WMARK_HIGH
] = min_wmark_pages(zone
) + tmp
* 2;
6440 __mod_zone_page_state(zone
, NR_ALLOC_BATCH
,
6441 high_wmark_pages(zone
) - low_wmark_pages(zone
) -
6442 atomic_long_read(&zone
->vm_stat
[NR_ALLOC_BATCH
]));
6444 spin_unlock_irqrestore(&zone
->lock
, flags
);
6447 /* update totalreserve_pages */
6448 calculate_totalreserve_pages();
6452 * setup_per_zone_wmarks - called when min_free_kbytes changes
6453 * or when memory is hot-{added|removed}
6455 * Ensures that the watermark[min,low,high] values for each zone are set
6456 * correctly with respect to min_free_kbytes.
6458 void setup_per_zone_wmarks(void)
6460 mutex_lock(&zonelists_mutex
);
6461 __setup_per_zone_wmarks();
6462 mutex_unlock(&zonelists_mutex
);
6466 * The inactive anon list should be small enough that the VM never has to
6467 * do too much work, but large enough that each inactive page has a chance
6468 * to be referenced again before it is swapped out.
6470 * The inactive_anon ratio is the target ratio of ACTIVE_ANON to
6471 * INACTIVE_ANON pages on this zone's LRU, maintained by the
6472 * pageout code. A zone->inactive_ratio of 3 means 3:1 or 25% of
6473 * the anonymous pages are kept on the inactive list.
6476 * memory ratio inactive anon
6477 * -------------------------------------
6486 static void __meminit
calculate_zone_inactive_ratio(struct zone
*zone
)
6488 unsigned int gb
, ratio
;
6490 /* Zone size in gigabytes */
6491 gb
= zone
->managed_pages
>> (30 - PAGE_SHIFT
);
6493 ratio
= int_sqrt(10 * gb
);
6497 zone
->inactive_ratio
= ratio
;
6500 static void __meminit
setup_per_zone_inactive_ratio(void)
6505 calculate_zone_inactive_ratio(zone
);
6509 * Initialise min_free_kbytes.
6511 * For small machines we want it small (128k min). For large machines
6512 * we want it large (64MB max). But it is not linear, because network
6513 * bandwidth does not increase linearly with machine size. We use
6515 * min_free_kbytes = 4 * sqrt(lowmem_kbytes), for better accuracy:
6516 * min_free_kbytes = sqrt(lowmem_kbytes * 16)
6532 int __meminit
init_per_zone_wmark_min(void)
6534 unsigned long lowmem_kbytes
;
6535 int new_min_free_kbytes
;
6537 lowmem_kbytes
= nr_free_buffer_pages() * (PAGE_SIZE
>> 10);
6538 new_min_free_kbytes
= int_sqrt(lowmem_kbytes
* 16);
6540 if (new_min_free_kbytes
> user_min_free_kbytes
) {
6541 min_free_kbytes
= new_min_free_kbytes
;
6542 if (min_free_kbytes
< 128)
6543 min_free_kbytes
= 128;
6544 if (min_free_kbytes
> 65536)
6545 min_free_kbytes
= 65536;
6547 pr_warn("min_free_kbytes is not updated to %d because user defined value %d is preferred\n",
6548 new_min_free_kbytes
, user_min_free_kbytes
);
6550 setup_per_zone_wmarks();
6551 refresh_zone_stat_thresholds();
6552 setup_per_zone_lowmem_reserve();
6553 setup_per_zone_inactive_ratio();
6556 core_initcall(init_per_zone_wmark_min
)
6559 * min_free_kbytes_sysctl_handler - just a wrapper around proc_dointvec() so
6560 * that we can call two helper functions whenever min_free_kbytes
6563 int min_free_kbytes_sysctl_handler(struct ctl_table
*table
, int write
,
6564 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
6568 rc
= proc_dointvec_minmax(table
, write
, buffer
, length
, ppos
);
6573 user_min_free_kbytes
= min_free_kbytes
;
6574 setup_per_zone_wmarks();
6579 int watermark_scale_factor_sysctl_handler(struct ctl_table
*table
, int write
,
6580 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
6584 rc
= proc_dointvec_minmax(table
, write
, buffer
, length
, ppos
);
6589 setup_per_zone_wmarks();
6595 int sysctl_min_unmapped_ratio_sysctl_handler(struct ctl_table
*table
, int write
,
6596 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
6601 rc
= proc_dointvec_minmax(table
, write
, buffer
, length
, ppos
);
6606 zone
->min_unmapped_pages
= (zone
->managed_pages
*
6607 sysctl_min_unmapped_ratio
) / 100;
6611 int sysctl_min_slab_ratio_sysctl_handler(struct ctl_table
*table
, int write
,
6612 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
6617 rc
= proc_dointvec_minmax(table
, write
, buffer
, length
, ppos
);
6622 zone
->min_slab_pages
= (zone
->managed_pages
*
6623 sysctl_min_slab_ratio
) / 100;
6629 * lowmem_reserve_ratio_sysctl_handler - just a wrapper around
6630 * proc_dointvec() so that we can call setup_per_zone_lowmem_reserve()
6631 * whenever sysctl_lowmem_reserve_ratio changes.
6633 * The reserve ratio obviously has absolutely no relation with the
6634 * minimum watermarks. The lowmem reserve ratio can only make sense
6635 * if in function of the boot time zone sizes.
6637 int lowmem_reserve_ratio_sysctl_handler(struct ctl_table
*table
, int write
,
6638 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
6640 proc_dointvec_minmax(table
, write
, buffer
, length
, ppos
);
6641 setup_per_zone_lowmem_reserve();
6646 * percpu_pagelist_fraction - changes the pcp->high for each zone on each
6647 * cpu. It is the fraction of total pages in each zone that a hot per cpu
6648 * pagelist can have before it gets flushed back to buddy allocator.
6650 int percpu_pagelist_fraction_sysctl_handler(struct ctl_table
*table
, int write
,
6651 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
6654 int old_percpu_pagelist_fraction
;
6657 mutex_lock(&pcp_batch_high_lock
);
6658 old_percpu_pagelist_fraction
= percpu_pagelist_fraction
;
6660 ret
= proc_dointvec_minmax(table
, write
, buffer
, length
, ppos
);
6661 if (!write
|| ret
< 0)
6664 /* Sanity checking to avoid pcp imbalance */
6665 if (percpu_pagelist_fraction
&&
6666 percpu_pagelist_fraction
< MIN_PERCPU_PAGELIST_FRACTION
) {
6667 percpu_pagelist_fraction
= old_percpu_pagelist_fraction
;
6673 if (percpu_pagelist_fraction
== old_percpu_pagelist_fraction
)
6676 for_each_populated_zone(zone
) {
6679 for_each_possible_cpu(cpu
)
6680 pageset_set_high_and_batch(zone
,
6681 per_cpu_ptr(zone
->pageset
, cpu
));
6684 mutex_unlock(&pcp_batch_high_lock
);
6689 int hashdist
= HASHDIST_DEFAULT
;
6691 static int __init
set_hashdist(char *str
)
6695 hashdist
= simple_strtoul(str
, &str
, 0);
6698 __setup("hashdist=", set_hashdist
);
6702 * allocate a large system hash table from bootmem
6703 * - it is assumed that the hash table must contain an exact power-of-2
6704 * quantity of entries
6705 * - limit is the number of hash buckets, not the total allocation size
6707 void *__init
alloc_large_system_hash(const char *tablename
,
6708 unsigned long bucketsize
,
6709 unsigned long numentries
,
6712 unsigned int *_hash_shift
,
6713 unsigned int *_hash_mask
,
6714 unsigned long low_limit
,
6715 unsigned long high_limit
)
6717 unsigned long long max
= high_limit
;
6718 unsigned long log2qty
, size
;
6721 /* allow the kernel cmdline to have a say */
6723 /* round applicable memory size up to nearest megabyte */
6724 numentries
= nr_kernel_pages
;
6726 /* It isn't necessary when PAGE_SIZE >= 1MB */
6727 if (PAGE_SHIFT
< 20)
6728 numentries
= round_up(numentries
, (1<<20)/PAGE_SIZE
);
6730 /* limit to 1 bucket per 2^scale bytes of low memory */
6731 if (scale
> PAGE_SHIFT
)
6732 numentries
>>= (scale
- PAGE_SHIFT
);
6734 numentries
<<= (PAGE_SHIFT
- scale
);
6736 /* Make sure we've got at least a 0-order allocation.. */
6737 if (unlikely(flags
& HASH_SMALL
)) {
6738 /* Makes no sense without HASH_EARLY */
6739 WARN_ON(!(flags
& HASH_EARLY
));
6740 if (!(numentries
>> *_hash_shift
)) {
6741 numentries
= 1UL << *_hash_shift
;
6742 BUG_ON(!numentries
);
6744 } else if (unlikely((numentries
* bucketsize
) < PAGE_SIZE
))
6745 numentries
= PAGE_SIZE
/ bucketsize
;
6747 numentries
= roundup_pow_of_two(numentries
);
6749 /* limit allocation size to 1/16 total memory by default */
6751 max
= ((unsigned long long)nr_all_pages
<< PAGE_SHIFT
) >> 4;
6752 do_div(max
, bucketsize
);
6754 max
= min(max
, 0x80000000ULL
);
6756 if (numentries
< low_limit
)
6757 numentries
= low_limit
;
6758 if (numentries
> max
)
6761 log2qty
= ilog2(numentries
);
6764 size
= bucketsize
<< log2qty
;
6765 if (flags
& HASH_EARLY
)
6766 table
= memblock_virt_alloc_nopanic(size
, 0);
6768 table
= __vmalloc(size
, GFP_ATOMIC
, PAGE_KERNEL
);
6771 * If bucketsize is not a power-of-two, we may free
6772 * some pages at the end of hash table which
6773 * alloc_pages_exact() automatically does
6775 if (get_order(size
) < MAX_ORDER
) {
6776 table
= alloc_pages_exact(size
, GFP_ATOMIC
);
6777 kmemleak_alloc(table
, size
, 1, GFP_ATOMIC
);
6780 } while (!table
&& size
> PAGE_SIZE
&& --log2qty
);
6783 panic("Failed to allocate %s hash table\n", tablename
);
6785 pr_info("%s hash table entries: %ld (order: %d, %lu bytes)\n",
6786 tablename
, 1UL << log2qty
, ilog2(size
) - PAGE_SHIFT
, size
);
6789 *_hash_shift
= log2qty
;
6791 *_hash_mask
= (1 << log2qty
) - 1;
6796 /* Return a pointer to the bitmap storing bits affecting a block of pages */
6797 static inline unsigned long *get_pageblock_bitmap(struct page
*page
,
6800 #ifdef CONFIG_SPARSEMEM
6801 return __pfn_to_section(pfn
)->pageblock_flags
;
6803 return page_zone(page
)->pageblock_flags
;
6804 #endif /* CONFIG_SPARSEMEM */
6807 static inline int pfn_to_bitidx(struct page
*page
, unsigned long pfn
)
6809 #ifdef CONFIG_SPARSEMEM
6810 pfn
&= (PAGES_PER_SECTION
-1);
6811 return (pfn
>> pageblock_order
) * NR_PAGEBLOCK_BITS
;
6813 pfn
= pfn
- round_down(page_zone(page
)->zone_start_pfn
, pageblock_nr_pages
);
6814 return (pfn
>> pageblock_order
) * NR_PAGEBLOCK_BITS
;
6815 #endif /* CONFIG_SPARSEMEM */
6819 * get_pfnblock_flags_mask - Return the requested group of flags for the pageblock_nr_pages block of pages
6820 * @page: The page within the block of interest
6821 * @pfn: The target page frame number
6822 * @end_bitidx: The last bit of interest to retrieve
6823 * @mask: mask of bits that the caller is interested in
6825 * Return: pageblock_bits flags
6827 unsigned long get_pfnblock_flags_mask(struct page
*page
, unsigned long pfn
,
6828 unsigned long end_bitidx
,
6831 unsigned long *bitmap
;
6832 unsigned long bitidx
, word_bitidx
;
6835 bitmap
= get_pageblock_bitmap(page
, pfn
);
6836 bitidx
= pfn_to_bitidx(page
, pfn
);
6837 word_bitidx
= bitidx
/ BITS_PER_LONG
;
6838 bitidx
&= (BITS_PER_LONG
-1);
6840 word
= bitmap
[word_bitidx
];
6841 bitidx
+= end_bitidx
;
6842 return (word
>> (BITS_PER_LONG
- bitidx
- 1)) & mask
;
6846 * set_pfnblock_flags_mask - Set the requested group of flags for a pageblock_nr_pages block of pages
6847 * @page: The page within the block of interest
6848 * @flags: The flags to set
6849 * @pfn: The target page frame number
6850 * @end_bitidx: The last bit of interest
6851 * @mask: mask of bits that the caller is interested in
6853 void set_pfnblock_flags_mask(struct page
*page
, unsigned long flags
,
6855 unsigned long end_bitidx
,
6858 unsigned long *bitmap
;
6859 unsigned long bitidx
, word_bitidx
;
6860 unsigned long old_word
, word
;
6862 BUILD_BUG_ON(NR_PAGEBLOCK_BITS
!= 4);
6864 bitmap
= get_pageblock_bitmap(page
, pfn
);
6865 bitidx
= pfn_to_bitidx(page
, pfn
);
6866 word_bitidx
= bitidx
/ BITS_PER_LONG
;
6867 bitidx
&= (BITS_PER_LONG
-1);
6869 VM_BUG_ON_PAGE(!zone_spans_pfn(page_zone(page
), pfn
), page
);
6871 bitidx
+= end_bitidx
;
6872 mask
<<= (BITS_PER_LONG
- bitidx
- 1);
6873 flags
<<= (BITS_PER_LONG
- bitidx
- 1);
6875 word
= READ_ONCE(bitmap
[word_bitidx
]);
6877 old_word
= cmpxchg(&bitmap
[word_bitidx
], word
, (word
& ~mask
) | flags
);
6878 if (word
== old_word
)
6885 * This function checks whether pageblock includes unmovable pages or not.
6886 * If @count is not zero, it is okay to include less @count unmovable pages
6888 * PageLRU check without isolation or lru_lock could race so that
6889 * MIGRATE_MOVABLE block might include unmovable pages. It means you can't
6890 * expect this function should be exact.
6892 bool has_unmovable_pages(struct zone
*zone
, struct page
*page
, int count
,
6893 bool skip_hwpoisoned_pages
)
6895 unsigned long pfn
, iter
, found
;
6899 * For avoiding noise data, lru_add_drain_all() should be called
6900 * If ZONE_MOVABLE, the zone never contains unmovable pages
6902 if (zone_idx(zone
) == ZONE_MOVABLE
)
6904 mt
= get_pageblock_migratetype(page
);
6905 if (mt
== MIGRATE_MOVABLE
|| is_migrate_cma(mt
))
6908 pfn
= page_to_pfn(page
);
6909 for (found
= 0, iter
= 0; iter
< pageblock_nr_pages
; iter
++) {
6910 unsigned long check
= pfn
+ iter
;
6912 if (!pfn_valid_within(check
))
6915 page
= pfn_to_page(check
);
6918 * Hugepages are not in LRU lists, but they're movable.
6919 * We need not scan over tail pages bacause we don't
6920 * handle each tail page individually in migration.
6922 if (PageHuge(page
)) {
6923 iter
= round_up(iter
+ 1, 1<<compound_order(page
)) - 1;
6928 * We can't use page_count without pin a page
6929 * because another CPU can free compound page.
6930 * This check already skips compound tails of THP
6931 * because their page->_refcount is zero at all time.
6933 if (!page_ref_count(page
)) {
6934 if (PageBuddy(page
))
6935 iter
+= (1 << page_order(page
)) - 1;
6940 * The HWPoisoned page may be not in buddy system, and
6941 * page_count() is not 0.
6943 if (skip_hwpoisoned_pages
&& PageHWPoison(page
))
6949 * If there are RECLAIMABLE pages, we need to check
6950 * it. But now, memory offline itself doesn't call
6951 * shrink_node_slabs() and it still to be fixed.
6954 * If the page is not RAM, page_count()should be 0.
6955 * we don't need more check. This is an _used_ not-movable page.
6957 * The problematic thing here is PG_reserved pages. PG_reserved
6958 * is set to both of a memory hole page and a _used_ kernel
6967 bool is_pageblock_removable_nolock(struct page
*page
)
6973 * We have to be careful here because we are iterating over memory
6974 * sections which are not zone aware so we might end up outside of
6975 * the zone but still within the section.
6976 * We have to take care about the node as well. If the node is offline
6977 * its NODE_DATA will be NULL - see page_zone.
6979 if (!node_online(page_to_nid(page
)))
6982 zone
= page_zone(page
);
6983 pfn
= page_to_pfn(page
);
6984 if (!zone_spans_pfn(zone
, pfn
))
6987 return !has_unmovable_pages(zone
, page
, 0, true);
6990 #if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)
6992 static unsigned long pfn_max_align_down(unsigned long pfn
)
6994 return pfn
& ~(max_t(unsigned long, MAX_ORDER_NR_PAGES
,
6995 pageblock_nr_pages
) - 1);
6998 static unsigned long pfn_max_align_up(unsigned long pfn
)
7000 return ALIGN(pfn
, max_t(unsigned long, MAX_ORDER_NR_PAGES
,
7001 pageblock_nr_pages
));
7004 /* [start, end) must belong to a single zone. */
7005 static int __alloc_contig_migrate_range(struct compact_control
*cc
,
7006 unsigned long start
, unsigned long end
)
7008 /* This function is based on compact_zone() from compaction.c. */
7009 unsigned long nr_reclaimed
;
7010 unsigned long pfn
= start
;
7011 unsigned int tries
= 0;
7016 while (pfn
< end
|| !list_empty(&cc
->migratepages
)) {
7017 if (fatal_signal_pending(current
)) {
7022 if (list_empty(&cc
->migratepages
)) {
7023 cc
->nr_migratepages
= 0;
7024 pfn
= isolate_migratepages_range(cc
, pfn
, end
);
7030 } else if (++tries
== 5) {
7031 ret
= ret
< 0 ? ret
: -EBUSY
;
7035 nr_reclaimed
= reclaim_clean_pages_from_list(cc
->zone
,
7037 cc
->nr_migratepages
-= nr_reclaimed
;
7039 ret
= migrate_pages(&cc
->migratepages
, alloc_migrate_target
,
7040 NULL
, 0, cc
->mode
, MR_CMA
);
7043 putback_movable_pages(&cc
->migratepages
);
7050 * alloc_contig_range() -- tries to allocate given range of pages
7051 * @start: start PFN to allocate
7052 * @end: one-past-the-last PFN to allocate
7053 * @migratetype: migratetype of the underlaying pageblocks (either
7054 * #MIGRATE_MOVABLE or #MIGRATE_CMA). All pageblocks
7055 * in range must have the same migratetype and it must
7056 * be either of the two.
7058 * The PFN range does not have to be pageblock or MAX_ORDER_NR_PAGES
7059 * aligned, however it's the caller's responsibility to guarantee that
7060 * we are the only thread that changes migrate type of pageblocks the
7063 * The PFN range must belong to a single zone.
7065 * Returns zero on success or negative error code. On success all
7066 * pages which PFN is in [start, end) are allocated for the caller and
7067 * need to be freed with free_contig_range().
7069 int alloc_contig_range(unsigned long start
, unsigned long end
,
7070 unsigned migratetype
)
7072 unsigned long outer_start
, outer_end
;
7076 struct compact_control cc
= {
7077 .nr_migratepages
= 0,
7079 .zone
= page_zone(pfn_to_page(start
)),
7080 .mode
= MIGRATE_SYNC
,
7081 .ignore_skip_hint
= true,
7083 INIT_LIST_HEAD(&cc
.migratepages
);
7086 * What we do here is we mark all pageblocks in range as
7087 * MIGRATE_ISOLATE. Because pageblock and max order pages may
7088 * have different sizes, and due to the way page allocator
7089 * work, we align the range to biggest of the two pages so
7090 * that page allocator won't try to merge buddies from
7091 * different pageblocks and change MIGRATE_ISOLATE to some
7092 * other migration type.
7094 * Once the pageblocks are marked as MIGRATE_ISOLATE, we
7095 * migrate the pages from an unaligned range (ie. pages that
7096 * we are interested in). This will put all the pages in
7097 * range back to page allocator as MIGRATE_ISOLATE.
7099 * When this is done, we take the pages in range from page
7100 * allocator removing them from the buddy system. This way
7101 * page allocator will never consider using them.
7103 * This lets us mark the pageblocks back as
7104 * MIGRATE_CMA/MIGRATE_MOVABLE so that free pages in the
7105 * aligned range but not in the unaligned, original range are
7106 * put back to page allocator so that buddy can use them.
7109 ret
= start_isolate_page_range(pfn_max_align_down(start
),
7110 pfn_max_align_up(end
), migratetype
,
7116 * In case of -EBUSY, we'd like to know which page causes problem.
7117 * So, just fall through. We will check it in test_pages_isolated().
7119 ret
= __alloc_contig_migrate_range(&cc
, start
, end
);
7120 if (ret
&& ret
!= -EBUSY
)
7124 * Pages from [start, end) are within a MAX_ORDER_NR_PAGES
7125 * aligned blocks that are marked as MIGRATE_ISOLATE. What's
7126 * more, all pages in [start, end) are free in page allocator.
7127 * What we are going to do is to allocate all pages from
7128 * [start, end) (that is remove them from page allocator).
7130 * The only problem is that pages at the beginning and at the
7131 * end of interesting range may be not aligned with pages that
7132 * page allocator holds, ie. they can be part of higher order
7133 * pages. Because of this, we reserve the bigger range and
7134 * once this is done free the pages we are not interested in.
7136 * We don't have to hold zone->lock here because the pages are
7137 * isolated thus they won't get removed from buddy.
7140 lru_add_drain_all();
7141 drain_all_pages(cc
.zone
);
7144 outer_start
= start
;
7145 while (!PageBuddy(pfn_to_page(outer_start
))) {
7146 if (++order
>= MAX_ORDER
) {
7147 outer_start
= start
;
7150 outer_start
&= ~0UL << order
;
7153 if (outer_start
!= start
) {
7154 order
= page_order(pfn_to_page(outer_start
));
7157 * outer_start page could be small order buddy page and
7158 * it doesn't include start page. Adjust outer_start
7159 * in this case to report failed page properly
7160 * on tracepoint in test_pages_isolated()
7162 if (outer_start
+ (1UL << order
) <= start
)
7163 outer_start
= start
;
7166 /* Make sure the range is really isolated. */
7167 if (test_pages_isolated(outer_start
, end
, false)) {
7168 pr_info("%s: [%lx, %lx) PFNs busy\n",
7169 __func__
, outer_start
, end
);
7174 /* Grab isolated pages from freelists. */
7175 outer_end
= isolate_freepages_range(&cc
, outer_start
, end
);
7181 /* Free head and tail (if any) */
7182 if (start
!= outer_start
)
7183 free_contig_range(outer_start
, start
- outer_start
);
7184 if (end
!= outer_end
)
7185 free_contig_range(end
, outer_end
- end
);
7188 undo_isolate_page_range(pfn_max_align_down(start
),
7189 pfn_max_align_up(end
), migratetype
);
7193 void free_contig_range(unsigned long pfn
, unsigned nr_pages
)
7195 unsigned int count
= 0;
7197 for (; nr_pages
--; pfn
++) {
7198 struct page
*page
= pfn_to_page(pfn
);
7200 count
+= page_count(page
) != 1;
7203 WARN(count
!= 0, "%d pages are still in use!\n", count
);
7207 #ifdef CONFIG_MEMORY_HOTPLUG
7209 * The zone indicated has a new number of managed_pages; batch sizes and percpu
7210 * page high values need to be recalulated.
7212 void __meminit
zone_pcp_update(struct zone
*zone
)
7215 mutex_lock(&pcp_batch_high_lock
);
7216 for_each_possible_cpu(cpu
)
7217 pageset_set_high_and_batch(zone
,
7218 per_cpu_ptr(zone
->pageset
, cpu
));
7219 mutex_unlock(&pcp_batch_high_lock
);
7223 void zone_pcp_reset(struct zone
*zone
)
7225 unsigned long flags
;
7227 struct per_cpu_pageset
*pset
;
7229 /* avoid races with drain_pages() */
7230 local_irq_save(flags
);
7231 if (zone
->pageset
!= &boot_pageset
) {
7232 for_each_online_cpu(cpu
) {
7233 pset
= per_cpu_ptr(zone
->pageset
, cpu
);
7234 drain_zonestat(zone
, pset
);
7236 free_percpu(zone
->pageset
);
7237 zone
->pageset
= &boot_pageset
;
7239 local_irq_restore(flags
);
7242 #ifdef CONFIG_MEMORY_HOTREMOVE
7244 * All pages in the range must be in a single zone and isolated
7245 * before calling this.
7248 __offline_isolated_pages(unsigned long start_pfn
, unsigned long end_pfn
)
7252 unsigned int order
, i
;
7254 unsigned long flags
;
7255 /* find the first valid pfn */
7256 for (pfn
= start_pfn
; pfn
< end_pfn
; pfn
++)
7261 zone
= page_zone(pfn_to_page(pfn
));
7262 spin_lock_irqsave(&zone
->lock
, flags
);
7264 while (pfn
< end_pfn
) {
7265 if (!pfn_valid(pfn
)) {
7269 page
= pfn_to_page(pfn
);
7271 * The HWPoisoned page may be not in buddy system, and
7272 * page_count() is not 0.
7274 if (unlikely(!PageBuddy(page
) && PageHWPoison(page
))) {
7276 SetPageReserved(page
);
7280 BUG_ON(page_count(page
));
7281 BUG_ON(!PageBuddy(page
));
7282 order
= page_order(page
);
7283 #ifdef CONFIG_DEBUG_VM
7284 pr_info("remove from free list %lx %d %lx\n",
7285 pfn
, 1 << order
, end_pfn
);
7287 list_del(&page
->lru
);
7288 rmv_page_order(page
);
7289 zone
->free_area
[order
].nr_free
--;
7290 for (i
= 0; i
< (1 << order
); i
++)
7291 SetPageReserved((page
+i
));
7292 pfn
+= (1 << order
);
7294 spin_unlock_irqrestore(&zone
->lock
, flags
);
7298 bool is_free_buddy_page(struct page
*page
)
7300 struct zone
*zone
= page_zone(page
);
7301 unsigned long pfn
= page_to_pfn(page
);
7302 unsigned long flags
;
7305 spin_lock_irqsave(&zone
->lock
, flags
);
7306 for (order
= 0; order
< MAX_ORDER
; order
++) {
7307 struct page
*page_head
= page
- (pfn
& ((1 << order
) - 1));
7309 if (PageBuddy(page_head
) && page_order(page_head
) >= order
)
7312 spin_unlock_irqrestore(&zone
->lock
, flags
);
7314 return order
< MAX_ORDER
;