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/module.h>
29 #include <linux/suspend.h>
30 #include <linux/pagevec.h>
31 #include <linux/blkdev.h>
32 #include <linux/slab.h>
33 #include <linux/oom.h>
34 #include <linux/notifier.h>
35 #include <linux/topology.h>
36 #include <linux/sysctl.h>
37 #include <linux/cpu.h>
38 #include <linux/cpuset.h>
39 #include <linux/memory_hotplug.h>
40 #include <linux/nodemask.h>
41 #include <linux/vmalloc.h>
42 #include <linux/mempolicy.h>
43 #include <linux/stop_machine.h>
44 #include <linux/sort.h>
45 #include <linux/pfn.h>
46 #include <linux/backing-dev.h>
47 #include <linux/fault-inject.h>
48 #include <linux/page-isolation.h>
49 #include <linux/page_cgroup.h>
50 #include <linux/debugobjects.h>
51 #include <linux/kmemleak.h>
52 #include <linux/memory.h>
53 #include <linux/compaction.h>
54 #include <trace/events/kmem.h>
55 #include <linux/ftrace_event.h>
57 #include <asm/tlbflush.h>
58 #include <asm/div64.h>
61 #ifdef CONFIG_USE_PERCPU_NUMA_NODE_ID
62 DEFINE_PER_CPU(int, numa_node);
63 EXPORT_PER_CPU_SYMBOL(numa_node);
66 #ifdef CONFIG_HAVE_MEMORYLESS_NODES
68 * N.B., Do NOT reference the '_numa_mem_' per cpu variable directly.
69 * It will not be defined when CONFIG_HAVE_MEMORYLESS_NODES is not defined.
70 * Use the accessor functions set_numa_mem(), numa_mem_id() and cpu_to_mem()
71 * defined in <linux/topology.h>.
73 DEFINE_PER_CPU(int, _numa_mem_); /* Kernel "local memory" node */
74 EXPORT_PER_CPU_SYMBOL(_numa_mem_);
78 * Array of node states.
80 nodemask_t node_states[NR_NODE_STATES] __read_mostly = {
81 [N_POSSIBLE] = NODE_MASK_ALL,
82 [N_ONLINE] = { { [0] = 1UL } },
84 [N_NORMAL_MEMORY] = { { [0] = 1UL } },
86 [N_HIGH_MEMORY] = { { [0] = 1UL } },
88 [N_CPU] = { { [0] = 1UL } },
91 EXPORT_SYMBOL(node_states);
93 unsigned long totalram_pages __read_mostly;
94 unsigned long totalreserve_pages __read_mostly;
95 int percpu_pagelist_fraction;
96 gfp_t gfp_allowed_mask __read_mostly = GFP_BOOT_MASK;
98 #ifdef CONFIG_PM_SLEEP
100 * The following functions are used by the suspend/hibernate code to temporarily
101 * change gfp_allowed_mask in order to avoid using I/O during memory allocations
102 * while devices are suspended. To avoid races with the suspend/hibernate code,
103 * they should always be called with pm_mutex held (gfp_allowed_mask also should
104 * only be modified with pm_mutex held, unless the suspend/hibernate code is
105 * guaranteed not to run in parallel with that modification).
108 static gfp_t saved_gfp_mask;
110 void pm_restore_gfp_mask(void)
112 WARN_ON(!mutex_is_locked(&pm_mutex));
113 if (saved_gfp_mask) {
114 gfp_allowed_mask = saved_gfp_mask;
119 void pm_restrict_gfp_mask(void)
121 WARN_ON(!mutex_is_locked(&pm_mutex));
122 WARN_ON(saved_gfp_mask);
123 saved_gfp_mask = gfp_allowed_mask;
124 gfp_allowed_mask &= ~GFP_IOFS;
126 #endif /* CONFIG_PM_SLEEP */
128 #ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
129 int pageblock_order __read_mostly;
132 static void __free_pages_ok(struct page *page, unsigned int order);
135 * results with 256, 32 in the lowmem_reserve sysctl:
136 * 1G machine -> (16M dma, 800M-16M normal, 1G-800M high)
137 * 1G machine -> (16M dma, 784M normal, 224M high)
138 * NORMAL allocation will leave 784M/256 of ram reserved in the ZONE_DMA
139 * HIGHMEM allocation will leave 224M/32 of ram reserved in ZONE_NORMAL
140 * HIGHMEM allocation will (224M+784M)/256 of ram reserved in ZONE_DMA
142 * TBD: should special case ZONE_DMA32 machines here - in those we normally
143 * don't need any ZONE_NORMAL reservation
145 int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES-1] = {
146 #ifdef CONFIG_ZONE_DMA
149 #ifdef CONFIG_ZONE_DMA32
152 #ifdef CONFIG_HIGHMEM
158 EXPORT_SYMBOL(totalram_pages);
160 static char * const zone_names[MAX_NR_ZONES] = {
161 #ifdef CONFIG_ZONE_DMA
164 #ifdef CONFIG_ZONE_DMA32
168 #ifdef CONFIG_HIGHMEM
174 int min_free_kbytes = 1024;
176 static unsigned long __meminitdata nr_kernel_pages;
177 static unsigned long __meminitdata nr_all_pages;
178 static unsigned long __meminitdata dma_reserve;
180 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
182 * MAX_ACTIVE_REGIONS determines the maximum number of distinct
183 * ranges of memory (RAM) that may be registered with add_active_range().
184 * Ranges passed to add_active_range() will be merged if possible
185 * so the number of times add_active_range() can be called is
186 * related to the number of nodes and the number of holes
188 #ifdef CONFIG_MAX_ACTIVE_REGIONS
189 /* Allow an architecture to set MAX_ACTIVE_REGIONS to save memory */
190 #define MAX_ACTIVE_REGIONS CONFIG_MAX_ACTIVE_REGIONS
192 #if MAX_NUMNODES >= 32
193 /* If there can be many nodes, allow up to 50 holes per node */
194 #define MAX_ACTIVE_REGIONS (MAX_NUMNODES*50)
196 /* By default, allow up to 256 distinct regions */
197 #define MAX_ACTIVE_REGIONS 256
201 static struct node_active_region __meminitdata early_node_map[MAX_ACTIVE_REGIONS];
202 static int __meminitdata nr_nodemap_entries;
203 static unsigned long __meminitdata arch_zone_lowest_possible_pfn[MAX_NR_ZONES];
204 static unsigned long __meminitdata arch_zone_highest_possible_pfn[MAX_NR_ZONES];
205 static unsigned long __initdata required_kernelcore;
206 static unsigned long __initdata required_movablecore;
207 static unsigned long __meminitdata zone_movable_pfn[MAX_NUMNODES];
209 /* movable_zone is the "real" zone pages in ZONE_MOVABLE are taken from */
211 EXPORT_SYMBOL(movable_zone);
212 #endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
215 int nr_node_ids __read_mostly = MAX_NUMNODES;
216 int nr_online_nodes __read_mostly = 1;
217 EXPORT_SYMBOL(nr_node_ids);
218 EXPORT_SYMBOL(nr_online_nodes);
221 int page_group_by_mobility_disabled __read_mostly;
223 static void set_pageblock_migratetype(struct page *page, int migratetype)
226 if (unlikely(page_group_by_mobility_disabled))
227 migratetype = MIGRATE_UNMOVABLE;
229 set_pageblock_flags_group(page, (unsigned long)migratetype,
230 PB_migrate, PB_migrate_end);
233 bool oom_killer_disabled __read_mostly;
235 #ifdef CONFIG_DEBUG_VM
236 static int page_outside_zone_boundaries(struct zone *zone, struct page *page)
240 unsigned long pfn = page_to_pfn(page);
243 seq = zone_span_seqbegin(zone);
244 if (pfn >= zone->zone_start_pfn + zone->spanned_pages)
246 else if (pfn < zone->zone_start_pfn)
248 } while (zone_span_seqretry(zone, seq));
253 static int page_is_consistent(struct zone *zone, struct page *page)
255 if (!pfn_valid_within(page_to_pfn(page)))
257 if (zone != page_zone(page))
263 * Temporary debugging check for pages not lying within a given zone.
265 static int bad_range(struct zone *zone, struct page *page)
267 if (page_outside_zone_boundaries(zone, page))
269 if (!page_is_consistent(zone, page))
275 static inline int bad_range(struct zone *zone, struct page *page)
281 static void bad_page(struct page *page)
283 static unsigned long resume;
284 static unsigned long nr_shown;
285 static unsigned long nr_unshown;
287 /* Don't complain about poisoned pages */
288 if (PageHWPoison(page)) {
289 reset_page_mapcount(page); /* remove PageBuddy */
294 * Allow a burst of 60 reports, then keep quiet for that minute;
295 * or allow a steady drip of one report per second.
297 if (nr_shown == 60) {
298 if (time_before(jiffies, resume)) {
304 "BUG: Bad page state: %lu messages suppressed\n",
311 resume = jiffies + 60 * HZ;
313 printk(KERN_ALERT "BUG: Bad page state in process %s pfn:%05lx\n",
314 current->comm, page_to_pfn(page));
319 /* Leave bad fields for debug, except PageBuddy could make trouble */
320 reset_page_mapcount(page); /* remove PageBuddy */
321 add_taint(TAINT_BAD_PAGE);
325 * Higher-order pages are called "compound pages". They are structured thusly:
327 * The first PAGE_SIZE page is called the "head page".
329 * The remaining PAGE_SIZE pages are called "tail pages".
331 * All pages have PG_compound set. All pages have their ->private pointing at
332 * the head page (even the head page has this).
334 * The first tail page's ->lru.next holds the address of the compound page's
335 * put_page() function. Its ->lru.prev holds the order of allocation.
336 * This usage means that zero-order pages may not be compound.
339 static void free_compound_page(struct page *page)
341 __free_pages_ok(page, compound_order(page));
344 void prep_compound_page(struct page *page, unsigned long order)
347 int nr_pages = 1 << order;
349 set_compound_page_dtor(page, free_compound_page);
350 set_compound_order(page, order);
352 for (i = 1; i < nr_pages; i++) {
353 struct page *p = page + i;
356 p->first_page = page;
360 /* update __split_huge_page_refcount if you change this function */
361 static int destroy_compound_page(struct page *page, unsigned long order)
364 int nr_pages = 1 << order;
367 if (unlikely(compound_order(page) != order) ||
368 unlikely(!PageHead(page))) {
373 __ClearPageHead(page);
375 for (i = 1; i < nr_pages; i++) {
376 struct page *p = page + i;
378 if (unlikely(!PageTail(p) || (p->first_page != page))) {
388 static inline void prep_zero_page(struct page *page, int order, gfp_t gfp_flags)
393 * clear_highpage() will use KM_USER0, so it's a bug to use __GFP_ZERO
394 * and __GFP_HIGHMEM from hard or soft interrupt context.
396 VM_BUG_ON((gfp_flags & __GFP_HIGHMEM) && in_interrupt());
397 for (i = 0; i < (1 << order); i++)
398 clear_highpage(page + i);
401 static inline void set_page_order(struct page *page, int order)
403 set_page_private(page, order);
404 __SetPageBuddy(page);
407 static inline void rmv_page_order(struct page *page)
409 __ClearPageBuddy(page);
410 set_page_private(page, 0);
414 * Locate the struct page for both the matching buddy in our
415 * pair (buddy1) and the combined O(n+1) page they form (page).
417 * 1) Any buddy B1 will have an order O twin B2 which satisfies
418 * the following equation:
420 * For example, if the starting buddy (buddy2) is #8 its order
422 * B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10
424 * 2) Any buddy B will have an order O+1 parent P which
425 * satisfies the following equation:
428 * Assumption: *_mem_map is contiguous at least up to MAX_ORDER
430 static inline unsigned long
431 __find_buddy_index(unsigned long page_idx, unsigned int order)
433 return page_idx ^ (1 << order);
437 * This function checks whether a page is free && is the buddy
438 * we can do coalesce a page and its buddy if
439 * (a) the buddy is not in a hole &&
440 * (b) the buddy is in the buddy system &&
441 * (c) a page and its buddy have the same order &&
442 * (d) a page and its buddy are in the same zone.
444 * For recording whether a page is in the buddy system, we set ->_mapcount -2.
445 * Setting, clearing, and testing _mapcount -2 is serialized by zone->lock.
447 * For recording page's order, we use page_private(page).
449 static inline int page_is_buddy(struct page *page, struct page *buddy,
452 if (!pfn_valid_within(page_to_pfn(buddy)))
455 if (page_zone_id(page) != page_zone_id(buddy))
458 if (PageBuddy(buddy) && page_order(buddy) == order) {
459 VM_BUG_ON(page_count(buddy) != 0);
466 * Freeing function for a buddy system allocator.
468 * The concept of a buddy system is to maintain direct-mapped table
469 * (containing bit values) for memory blocks of various "orders".
470 * The bottom level table contains the map for the smallest allocatable
471 * units of memory (here, pages), and each level above it describes
472 * pairs of units from the levels below, hence, "buddies".
473 * At a high level, all that happens here is marking the table entry
474 * at the bottom level available, and propagating the changes upward
475 * as necessary, plus some accounting needed to play nicely with other
476 * parts of the VM system.
477 * At each level, we keep a list of pages, which are heads of continuous
478 * free pages of length of (1 << order) and marked with _mapcount -2. Page's
479 * order is recorded in page_private(page) field.
480 * So when we are allocating or freeing one, we can derive the state of the
481 * other. That is, if we allocate a small block, and both were
482 * free, the remainder of the region must be split into blocks.
483 * If a block is freed, and its buddy is also free, then this
484 * triggers coalescing into a block of larger size.
489 static inline void __free_one_page(struct page *page,
490 struct zone *zone, unsigned int order,
493 unsigned long page_idx;
494 unsigned long combined_idx;
495 unsigned long uninitialized_var(buddy_idx);
498 if (unlikely(PageCompound(page)))
499 if (unlikely(destroy_compound_page(page, order)))
502 VM_BUG_ON(migratetype == -1);
504 page_idx = page_to_pfn(page) & ((1 << MAX_ORDER) - 1);
506 VM_BUG_ON(page_idx & ((1 << order) - 1));
507 VM_BUG_ON(bad_range(zone, page));
509 while (order < MAX_ORDER-1) {
510 buddy_idx = __find_buddy_index(page_idx, order);
511 buddy = page + (buddy_idx - page_idx);
512 if (!page_is_buddy(page, buddy, order))
515 /* Our buddy is free, merge with it and move up one order. */
516 list_del(&buddy->lru);
517 zone->free_area[order].nr_free--;
518 rmv_page_order(buddy);
519 combined_idx = buddy_idx & page_idx;
520 page = page + (combined_idx - page_idx);
521 page_idx = combined_idx;
524 set_page_order(page, order);
527 * If this is not the largest possible page, check if the buddy
528 * of the next-highest order is free. If it is, it's possible
529 * that pages are being freed that will coalesce soon. In case,
530 * that is happening, add the free page to the tail of the list
531 * so it's less likely to be used soon and more likely to be merged
532 * as a higher order page
534 if ((order < MAX_ORDER-2) && pfn_valid_within(page_to_pfn(buddy))) {
535 struct page *higher_page, *higher_buddy;
536 combined_idx = buddy_idx & page_idx;
537 higher_page = page + (combined_idx - page_idx);
538 buddy_idx = __find_buddy_index(combined_idx, order + 1);
539 higher_buddy = page + (buddy_idx - combined_idx);
540 if (page_is_buddy(higher_page, higher_buddy, order + 1)) {
541 list_add_tail(&page->lru,
542 &zone->free_area[order].free_list[migratetype]);
547 list_add(&page->lru, &zone->free_area[order].free_list[migratetype]);
549 zone->free_area[order].nr_free++;
553 * free_page_mlock() -- clean up attempts to free and mlocked() page.
554 * Page should not be on lru, so no need to fix that up.
555 * free_pages_check() will verify...
557 static inline void free_page_mlock(struct page *page)
559 __dec_zone_page_state(page, NR_MLOCK);
560 __count_vm_event(UNEVICTABLE_MLOCKFREED);
563 static inline int free_pages_check(struct page *page)
565 if (unlikely(page_mapcount(page) |
566 (page->mapping != NULL) |
567 (atomic_read(&page->_count) != 0) |
568 (page->flags & PAGE_FLAGS_CHECK_AT_FREE))) {
572 if (page->flags & PAGE_FLAGS_CHECK_AT_PREP)
573 page->flags &= ~PAGE_FLAGS_CHECK_AT_PREP;
578 * Frees a number of pages from the PCP lists
579 * Assumes all pages on list are in same zone, and of same order.
580 * count is the number of pages to free.
582 * If the zone was previously in an "all pages pinned" state then look to
583 * see if this freeing clears that state.
585 * And clear the zone's pages_scanned counter, to hold off the "all pages are
586 * pinned" detection logic.
588 static void free_pcppages_bulk(struct zone *zone, int count,
589 struct per_cpu_pages *pcp)
595 spin_lock(&zone->lock);
596 zone->all_unreclaimable = 0;
597 zone->pages_scanned = 0;
601 struct list_head *list;
604 * Remove pages from lists in a round-robin fashion. A
605 * batch_free count is maintained that is incremented when an
606 * empty list is encountered. This is so more pages are freed
607 * off fuller lists instead of spinning excessively around empty
612 if (++migratetype == MIGRATE_PCPTYPES)
614 list = &pcp->lists[migratetype];
615 } while (list_empty(list));
618 page = list_entry(list->prev, struct page, lru);
619 /* must delete as __free_one_page list manipulates */
620 list_del(&page->lru);
621 /* MIGRATE_MOVABLE list may include MIGRATE_RESERVEs */
622 __free_one_page(page, zone, 0, page_private(page));
623 trace_mm_page_pcpu_drain(page, 0, page_private(page));
624 } while (--to_free && --batch_free && !list_empty(list));
626 __mod_zone_page_state(zone, NR_FREE_PAGES, count);
627 spin_unlock(&zone->lock);
630 static void free_one_page(struct zone *zone, struct page *page, int order,
633 spin_lock(&zone->lock);
634 zone->all_unreclaimable = 0;
635 zone->pages_scanned = 0;
637 __free_one_page(page, zone, order, migratetype);
638 __mod_zone_page_state(zone, NR_FREE_PAGES, 1 << order);
639 spin_unlock(&zone->lock);
642 static bool free_pages_prepare(struct page *page, unsigned int order)
647 trace_mm_page_free_direct(page, order);
648 kmemcheck_free_shadow(page, order);
651 page->mapping = NULL;
652 for (i = 0; i < (1 << order); i++)
653 bad += free_pages_check(page + i);
657 if (!PageHighMem(page)) {
658 debug_check_no_locks_freed(page_address(page),PAGE_SIZE<<order);
659 debug_check_no_obj_freed(page_address(page),
662 arch_free_page(page, order);
663 kernel_map_pages(page, 1 << order, 0);
668 static void __free_pages_ok(struct page *page, unsigned int order)
671 int wasMlocked = __TestClearPageMlocked(page);
673 if (!free_pages_prepare(page, order))
676 local_irq_save(flags);
677 if (unlikely(wasMlocked))
678 free_page_mlock(page);
679 __count_vm_events(PGFREE, 1 << order);
680 free_one_page(page_zone(page), page, order,
681 get_pageblock_migratetype(page));
682 local_irq_restore(flags);
686 * permit the bootmem allocator to evade page validation on high-order frees
688 void __meminit __free_pages_bootmem(struct page *page, unsigned int order)
691 __ClearPageReserved(page);
692 set_page_count(page, 0);
693 set_page_refcounted(page);
699 for (loop = 0; loop < BITS_PER_LONG; loop++) {
700 struct page *p = &page[loop];
702 if (loop + 1 < BITS_PER_LONG)
704 __ClearPageReserved(p);
705 set_page_count(p, 0);
708 set_page_refcounted(page);
709 __free_pages(page, order);
715 * The order of subdivision here is critical for the IO subsystem.
716 * Please do not alter this order without good reasons and regression
717 * testing. Specifically, as large blocks of memory are subdivided,
718 * the order in which smaller blocks are delivered depends on the order
719 * they're subdivided in this function. This is the primary factor
720 * influencing the order in which pages are delivered to the IO
721 * subsystem according to empirical testing, and this is also justified
722 * by considering the behavior of a buddy system containing a single
723 * large block of memory acted on by a series of small allocations.
724 * This behavior is a critical factor in sglist merging's success.
728 static inline void expand(struct zone *zone, struct page *page,
729 int low, int high, struct free_area *area,
732 unsigned long size = 1 << high;
738 VM_BUG_ON(bad_range(zone, &page[size]));
739 list_add(&page[size].lru, &area->free_list[migratetype]);
741 set_page_order(&page[size], high);
746 * This page is about to be returned from the page allocator
748 static inline int check_new_page(struct page *page)
750 if (unlikely(page_mapcount(page) |
751 (page->mapping != NULL) |
752 (atomic_read(&page->_count) != 0) |
753 (page->flags & PAGE_FLAGS_CHECK_AT_PREP))) {
760 static int prep_new_page(struct page *page, int order, gfp_t gfp_flags)
764 for (i = 0; i < (1 << order); i++) {
765 struct page *p = page + i;
766 if (unlikely(check_new_page(p)))
770 set_page_private(page, 0);
771 set_page_refcounted(page);
773 arch_alloc_page(page, order);
774 kernel_map_pages(page, 1 << order, 1);
776 if (gfp_flags & __GFP_ZERO)
777 prep_zero_page(page, order, gfp_flags);
779 if (order && (gfp_flags & __GFP_COMP))
780 prep_compound_page(page, order);
786 * Go through the free lists for the given migratetype and remove
787 * the smallest available page from the freelists
790 struct page *__rmqueue_smallest(struct zone *zone, unsigned int order,
793 unsigned int current_order;
794 struct free_area * area;
797 /* Find a page of the appropriate size in the preferred list */
798 for (current_order = order; current_order < MAX_ORDER; ++current_order) {
799 area = &(zone->free_area[current_order]);
800 if (list_empty(&area->free_list[migratetype]))
803 page = list_entry(area->free_list[migratetype].next,
805 list_del(&page->lru);
806 rmv_page_order(page);
808 expand(zone, page, order, current_order, area, migratetype);
817 * This array describes the order lists are fallen back to when
818 * the free lists for the desirable migrate type are depleted
820 static int fallbacks[MIGRATE_TYPES][MIGRATE_TYPES-1] = {
821 [MIGRATE_UNMOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_MOVABLE, MIGRATE_RESERVE },
822 [MIGRATE_RECLAIMABLE] = { MIGRATE_UNMOVABLE, MIGRATE_MOVABLE, MIGRATE_RESERVE },
823 [MIGRATE_MOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE, MIGRATE_RESERVE },
824 [MIGRATE_RESERVE] = { MIGRATE_RESERVE, MIGRATE_RESERVE, MIGRATE_RESERVE }, /* Never used */
828 * Move the free pages in a range to the free lists of the requested type.
829 * Note that start_page and end_pages are not aligned on a pageblock
830 * boundary. If alignment is required, use move_freepages_block()
832 static int move_freepages(struct zone *zone,
833 struct page *start_page, struct page *end_page,
840 #ifndef CONFIG_HOLES_IN_ZONE
842 * page_zone is not safe to call in this context when
843 * CONFIG_HOLES_IN_ZONE is set. This bug check is probably redundant
844 * anyway as we check zone boundaries in move_freepages_block().
845 * Remove at a later date when no bug reports exist related to
846 * grouping pages by mobility
848 BUG_ON(page_zone(start_page) != page_zone(end_page));
851 for (page = start_page; page <= end_page;) {
852 /* Make sure we are not inadvertently changing nodes */
853 VM_BUG_ON(page_to_nid(page) != zone_to_nid(zone));
855 if (!pfn_valid_within(page_to_pfn(page))) {
860 if (!PageBuddy(page)) {
865 order = page_order(page);
866 list_del(&page->lru);
868 &zone->free_area[order].free_list[migratetype]);
870 pages_moved += 1 << order;
876 static int move_freepages_block(struct zone *zone, struct page *page,
879 unsigned long start_pfn, end_pfn;
880 struct page *start_page, *end_page;
882 start_pfn = page_to_pfn(page);
883 start_pfn = start_pfn & ~(pageblock_nr_pages-1);
884 start_page = pfn_to_page(start_pfn);
885 end_page = start_page + pageblock_nr_pages - 1;
886 end_pfn = start_pfn + pageblock_nr_pages - 1;
888 /* Do not cross zone boundaries */
889 if (start_pfn < zone->zone_start_pfn)
891 if (end_pfn >= zone->zone_start_pfn + zone->spanned_pages)
894 return move_freepages(zone, start_page, end_page, migratetype);
897 static void change_pageblock_range(struct page *pageblock_page,
898 int start_order, int migratetype)
900 int nr_pageblocks = 1 << (start_order - pageblock_order);
902 while (nr_pageblocks--) {
903 set_pageblock_migratetype(pageblock_page, migratetype);
904 pageblock_page += pageblock_nr_pages;
908 /* Remove an element from the buddy allocator from the fallback list */
909 static inline struct page *
910 __rmqueue_fallback(struct zone *zone, int order, int start_migratetype)
912 struct free_area * area;
917 /* Find the largest possible block of pages in the other list */
918 for (current_order = MAX_ORDER-1; current_order >= order;
920 for (i = 0; i < MIGRATE_TYPES - 1; i++) {
921 migratetype = fallbacks[start_migratetype][i];
923 /* MIGRATE_RESERVE handled later if necessary */
924 if (migratetype == MIGRATE_RESERVE)
927 area = &(zone->free_area[current_order]);
928 if (list_empty(&area->free_list[migratetype]))
931 page = list_entry(area->free_list[migratetype].next,
936 * If breaking a large block of pages, move all free
937 * pages to the preferred allocation list. If falling
938 * back for a reclaimable kernel allocation, be more
939 * agressive about taking ownership of free pages
941 if (unlikely(current_order >= (pageblock_order >> 1)) ||
942 start_migratetype == MIGRATE_RECLAIMABLE ||
943 page_group_by_mobility_disabled) {
945 pages = move_freepages_block(zone, page,
948 /* Claim the whole block if over half of it is free */
949 if (pages >= (1 << (pageblock_order-1)) ||
950 page_group_by_mobility_disabled)
951 set_pageblock_migratetype(page,
954 migratetype = start_migratetype;
957 /* Remove the page from the freelists */
958 list_del(&page->lru);
959 rmv_page_order(page);
961 /* Take ownership for orders >= pageblock_order */
962 if (current_order >= pageblock_order)
963 change_pageblock_range(page, current_order,
966 expand(zone, page, order, current_order, area, migratetype);
968 trace_mm_page_alloc_extfrag(page, order, current_order,
969 start_migratetype, migratetype);
979 * Do the hard work of removing an element from the buddy allocator.
980 * Call me with the zone->lock already held.
982 static struct page *__rmqueue(struct zone *zone, unsigned int order,
988 page = __rmqueue_smallest(zone, order, migratetype);
990 if (unlikely(!page) && migratetype != MIGRATE_RESERVE) {
991 page = __rmqueue_fallback(zone, order, migratetype);
994 * Use MIGRATE_RESERVE rather than fail an allocation. goto
995 * is used because __rmqueue_smallest is an inline function
996 * and we want just one call site
999 migratetype = MIGRATE_RESERVE;
1004 trace_mm_page_alloc_zone_locked(page, order, migratetype);
1009 * Obtain a specified number of elements from the buddy allocator, all under
1010 * a single hold of the lock, for efficiency. Add them to the supplied list.
1011 * Returns the number of new pages which were placed at *list.
1013 static int rmqueue_bulk(struct zone *zone, unsigned int order,
1014 unsigned long count, struct list_head *list,
1015 int migratetype, int cold)
1019 spin_lock(&zone->lock);
1020 for (i = 0; i < count; ++i) {
1021 struct page *page = __rmqueue(zone, order, migratetype);
1022 if (unlikely(page == NULL))
1026 * Split buddy pages returned by expand() are received here
1027 * in physical page order. The page is added to the callers and
1028 * list and the list head then moves forward. From the callers
1029 * perspective, the linked list is ordered by page number in
1030 * some conditions. This is useful for IO devices that can
1031 * merge IO requests if the physical pages are ordered
1034 if (likely(cold == 0))
1035 list_add(&page->lru, list);
1037 list_add_tail(&page->lru, list);
1038 set_page_private(page, migratetype);
1041 __mod_zone_page_state(zone, NR_FREE_PAGES, -(i << order));
1042 spin_unlock(&zone->lock);
1048 * Called from the vmstat counter updater to drain pagesets of this
1049 * currently executing processor on remote nodes after they have
1052 * Note that this function must be called with the thread pinned to
1053 * a single processor.
1055 void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp)
1057 unsigned long flags;
1060 local_irq_save(flags);
1061 if (pcp->count >= pcp->batch)
1062 to_drain = pcp->batch;
1064 to_drain = pcp->count;
1065 free_pcppages_bulk(zone, to_drain, pcp);
1066 pcp->count -= to_drain;
1067 local_irq_restore(flags);
1072 * Drain pages of the indicated processor.
1074 * The processor must either be the current processor and the
1075 * thread pinned to the current processor or a processor that
1078 static void drain_pages(unsigned int cpu)
1080 unsigned long flags;
1083 for_each_populated_zone(zone) {
1084 struct per_cpu_pageset *pset;
1085 struct per_cpu_pages *pcp;
1087 local_irq_save(flags);
1088 pset = per_cpu_ptr(zone->pageset, cpu);
1092 free_pcppages_bulk(zone, pcp->count, pcp);
1095 local_irq_restore(flags);
1100 * Spill all of this CPU's per-cpu pages back into the buddy allocator.
1102 void drain_local_pages(void *arg)
1104 drain_pages(smp_processor_id());
1108 * Spill all the per-cpu pages from all CPUs back into the buddy allocator
1110 void drain_all_pages(void)
1112 on_each_cpu(drain_local_pages, NULL, 1);
1115 #ifdef CONFIG_HIBERNATION
1117 void mark_free_pages(struct zone *zone)
1119 unsigned long pfn, max_zone_pfn;
1120 unsigned long flags;
1122 struct list_head *curr;
1124 if (!zone->spanned_pages)
1127 spin_lock_irqsave(&zone->lock, flags);
1129 max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
1130 for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
1131 if (pfn_valid(pfn)) {
1132 struct page *page = pfn_to_page(pfn);
1134 if (!swsusp_page_is_forbidden(page))
1135 swsusp_unset_page_free(page);
1138 for_each_migratetype_order(order, t) {
1139 list_for_each(curr, &zone->free_area[order].free_list[t]) {
1142 pfn = page_to_pfn(list_entry(curr, struct page, lru));
1143 for (i = 0; i < (1UL << order); i++)
1144 swsusp_set_page_free(pfn_to_page(pfn + i));
1147 spin_unlock_irqrestore(&zone->lock, flags);
1149 #endif /* CONFIG_PM */
1152 * Free a 0-order page
1153 * cold == 1 ? free a cold page : free a hot page
1155 void free_hot_cold_page(struct page *page, int cold)
1157 struct zone *zone = page_zone(page);
1158 struct per_cpu_pages *pcp;
1159 unsigned long flags;
1161 int wasMlocked = __TestClearPageMlocked(page);
1163 if (!free_pages_prepare(page, 0))
1166 migratetype = get_pageblock_migratetype(page);
1167 set_page_private(page, migratetype);
1168 local_irq_save(flags);
1169 if (unlikely(wasMlocked))
1170 free_page_mlock(page);
1171 __count_vm_event(PGFREE);
1174 * We only track unmovable, reclaimable and movable on pcp lists.
1175 * Free ISOLATE pages back to the allocator because they are being
1176 * offlined but treat RESERVE as movable pages so we can get those
1177 * areas back if necessary. Otherwise, we may have to free
1178 * excessively into the page allocator
1180 if (migratetype >= MIGRATE_PCPTYPES) {
1181 if (unlikely(migratetype == MIGRATE_ISOLATE)) {
1182 free_one_page(zone, page, 0, migratetype);
1185 migratetype = MIGRATE_MOVABLE;
1188 pcp = &this_cpu_ptr(zone->pageset)->pcp;
1190 list_add_tail(&page->lru, &pcp->lists[migratetype]);
1192 list_add(&page->lru, &pcp->lists[migratetype]);
1194 if (pcp->count >= pcp->high) {
1195 free_pcppages_bulk(zone, pcp->batch, pcp);
1196 pcp->count -= pcp->batch;
1200 local_irq_restore(flags);
1204 * split_page takes a non-compound higher-order page, and splits it into
1205 * n (1<<order) sub-pages: page[0..n]
1206 * Each sub-page must be freed individually.
1208 * Note: this is probably too low level an operation for use in drivers.
1209 * Please consult with lkml before using this in your driver.
1211 void split_page(struct page *page, unsigned int order)
1215 VM_BUG_ON(PageCompound(page));
1216 VM_BUG_ON(!page_count(page));
1218 #ifdef CONFIG_KMEMCHECK
1220 * Split shadow pages too, because free(page[0]) would
1221 * otherwise free the whole shadow.
1223 if (kmemcheck_page_is_tracked(page))
1224 split_page(virt_to_page(page[0].shadow), order);
1227 for (i = 1; i < (1 << order); i++)
1228 set_page_refcounted(page + i);
1232 * Similar to split_page except the page is already free. As this is only
1233 * being used for migration, the migratetype of the block also changes.
1234 * As this is called with interrupts disabled, the caller is responsible
1235 * for calling arch_alloc_page() and kernel_map_page() after interrupts
1238 * Note: this is probably too low level an operation for use in drivers.
1239 * Please consult with lkml before using this in your driver.
1241 int split_free_page(struct page *page)
1244 unsigned long watermark;
1247 BUG_ON(!PageBuddy(page));
1249 zone = page_zone(page);
1250 order = page_order(page);
1252 /* Obey watermarks as if the page was being allocated */
1253 watermark = low_wmark_pages(zone) + (1 << order);
1254 if (!zone_watermark_ok(zone, 0, watermark, 0, 0))
1257 /* Remove page from free list */
1258 list_del(&page->lru);
1259 zone->free_area[order].nr_free--;
1260 rmv_page_order(page);
1261 __mod_zone_page_state(zone, NR_FREE_PAGES, -(1UL << order));
1263 /* Split into individual pages */
1264 set_page_refcounted(page);
1265 split_page(page, order);
1267 if (order >= pageblock_order - 1) {
1268 struct page *endpage = page + (1 << order) - 1;
1269 for (; page < endpage; page += pageblock_nr_pages)
1270 set_pageblock_migratetype(page, MIGRATE_MOVABLE);
1277 * Really, prep_compound_page() should be called from __rmqueue_bulk(). But
1278 * we cheat by calling it from here, in the order > 0 path. Saves a branch
1282 struct page *buffered_rmqueue(struct zone *preferred_zone,
1283 struct zone *zone, int order, gfp_t gfp_flags,
1286 unsigned long flags;
1288 int cold = !!(gfp_flags & __GFP_COLD);
1291 if (likely(order == 0)) {
1292 struct per_cpu_pages *pcp;
1293 struct list_head *list;
1295 local_irq_save(flags);
1296 pcp = &this_cpu_ptr(zone->pageset)->pcp;
1297 list = &pcp->lists[migratetype];
1298 if (list_empty(list)) {
1299 pcp->count += rmqueue_bulk(zone, 0,
1302 if (unlikely(list_empty(list)))
1307 page = list_entry(list->prev, struct page, lru);
1309 page = list_entry(list->next, struct page, lru);
1311 list_del(&page->lru);
1314 if (unlikely(gfp_flags & __GFP_NOFAIL)) {
1316 * __GFP_NOFAIL is not to be used in new code.
1318 * All __GFP_NOFAIL callers should be fixed so that they
1319 * properly detect and handle allocation failures.
1321 * We most definitely don't want callers attempting to
1322 * allocate greater than order-1 page units with
1325 WARN_ON_ONCE(order > 1);
1327 spin_lock_irqsave(&zone->lock, flags);
1328 page = __rmqueue(zone, order, migratetype);
1329 spin_unlock(&zone->lock);
1332 __mod_zone_page_state(zone, NR_FREE_PAGES, -(1 << order));
1335 __count_zone_vm_events(PGALLOC, zone, 1 << order);
1336 zone_statistics(preferred_zone, zone);
1337 local_irq_restore(flags);
1339 VM_BUG_ON(bad_range(zone, page));
1340 if (prep_new_page(page, order, gfp_flags))
1345 local_irq_restore(flags);
1349 /* The ALLOC_WMARK bits are used as an index to zone->watermark */
1350 #define ALLOC_WMARK_MIN WMARK_MIN
1351 #define ALLOC_WMARK_LOW WMARK_LOW
1352 #define ALLOC_WMARK_HIGH WMARK_HIGH
1353 #define ALLOC_NO_WATERMARKS 0x04 /* don't check watermarks at all */
1355 /* Mask to get the watermark bits */
1356 #define ALLOC_WMARK_MASK (ALLOC_NO_WATERMARKS-1)
1358 #define ALLOC_HARDER 0x10 /* try to alloc harder */
1359 #define ALLOC_HIGH 0x20 /* __GFP_HIGH set */
1360 #define ALLOC_CPUSET 0x40 /* check for correct cpuset */
1362 #ifdef CONFIG_FAIL_PAGE_ALLOC
1364 static struct fail_page_alloc_attr {
1365 struct fault_attr attr;
1367 u32 ignore_gfp_highmem;
1368 u32 ignore_gfp_wait;
1371 #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
1373 struct dentry *ignore_gfp_highmem_file;
1374 struct dentry *ignore_gfp_wait_file;
1375 struct dentry *min_order_file;
1377 #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
1379 } fail_page_alloc = {
1380 .attr = FAULT_ATTR_INITIALIZER,
1381 .ignore_gfp_wait = 1,
1382 .ignore_gfp_highmem = 1,
1386 static int __init setup_fail_page_alloc(char *str)
1388 return setup_fault_attr(&fail_page_alloc.attr, str);
1390 __setup("fail_page_alloc=", setup_fail_page_alloc);
1392 static int should_fail_alloc_page(gfp_t gfp_mask, unsigned int order)
1394 if (order < fail_page_alloc.min_order)
1396 if (gfp_mask & __GFP_NOFAIL)
1398 if (fail_page_alloc.ignore_gfp_highmem && (gfp_mask & __GFP_HIGHMEM))
1400 if (fail_page_alloc.ignore_gfp_wait && (gfp_mask & __GFP_WAIT))
1403 return should_fail(&fail_page_alloc.attr, 1 << order);
1406 #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
1408 static int __init fail_page_alloc_debugfs(void)
1410 mode_t mode = S_IFREG | S_IRUSR | S_IWUSR;
1414 err = init_fault_attr_dentries(&fail_page_alloc.attr,
1418 dir = fail_page_alloc.attr.dentries.dir;
1420 fail_page_alloc.ignore_gfp_wait_file =
1421 debugfs_create_bool("ignore-gfp-wait", mode, dir,
1422 &fail_page_alloc.ignore_gfp_wait);
1424 fail_page_alloc.ignore_gfp_highmem_file =
1425 debugfs_create_bool("ignore-gfp-highmem", mode, dir,
1426 &fail_page_alloc.ignore_gfp_highmem);
1427 fail_page_alloc.min_order_file =
1428 debugfs_create_u32("min-order", mode, dir,
1429 &fail_page_alloc.min_order);
1431 if (!fail_page_alloc.ignore_gfp_wait_file ||
1432 !fail_page_alloc.ignore_gfp_highmem_file ||
1433 !fail_page_alloc.min_order_file) {
1435 debugfs_remove(fail_page_alloc.ignore_gfp_wait_file);
1436 debugfs_remove(fail_page_alloc.ignore_gfp_highmem_file);
1437 debugfs_remove(fail_page_alloc.min_order_file);
1438 cleanup_fault_attr_dentries(&fail_page_alloc.attr);
1444 late_initcall(fail_page_alloc_debugfs);
1446 #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
1448 #else /* CONFIG_FAIL_PAGE_ALLOC */
1450 static inline int should_fail_alloc_page(gfp_t gfp_mask, unsigned int order)
1455 #endif /* CONFIG_FAIL_PAGE_ALLOC */
1458 * Return true if free pages are above 'mark'. This takes into account the order
1459 * of the allocation.
1461 static bool __zone_watermark_ok(struct zone *z, int order, unsigned long mark,
1462 int classzone_idx, int alloc_flags, long free_pages)
1464 /* free_pages my go negative - that's OK */
1468 free_pages -= (1 << order) + 1;
1469 if (alloc_flags & ALLOC_HIGH)
1471 if (alloc_flags & ALLOC_HARDER)
1474 if (free_pages <= min + z->lowmem_reserve[classzone_idx])
1476 for (o = 0; o < order; o++) {
1477 /* At the next order, this order's pages become unavailable */
1478 free_pages -= z->free_area[o].nr_free << o;
1480 /* Require fewer higher order pages to be free */
1483 if (free_pages <= min)
1489 bool zone_watermark_ok(struct zone *z, int order, unsigned long mark,
1490 int classzone_idx, int alloc_flags)
1492 return __zone_watermark_ok(z, order, mark, classzone_idx, alloc_flags,
1493 zone_page_state(z, NR_FREE_PAGES));
1496 bool zone_watermark_ok_safe(struct zone *z, int order, unsigned long mark,
1497 int classzone_idx, int alloc_flags)
1499 long free_pages = zone_page_state(z, NR_FREE_PAGES);
1501 if (z->percpu_drift_mark && free_pages < z->percpu_drift_mark)
1502 free_pages = zone_page_state_snapshot(z, NR_FREE_PAGES);
1504 return __zone_watermark_ok(z, order, mark, classzone_idx, alloc_flags,
1510 * zlc_setup - Setup for "zonelist cache". Uses cached zone data to
1511 * skip over zones that are not allowed by the cpuset, or that have
1512 * been recently (in last second) found to be nearly full. See further
1513 * comments in mmzone.h. Reduces cache footprint of zonelist scans
1514 * that have to skip over a lot of full or unallowed zones.
1516 * If the zonelist cache is present in the passed in zonelist, then
1517 * returns a pointer to the allowed node mask (either the current
1518 * tasks mems_allowed, or node_states[N_HIGH_MEMORY].)
1520 * If the zonelist cache is not available for this zonelist, does
1521 * nothing and returns NULL.
1523 * If the fullzones BITMAP in the zonelist cache is stale (more than
1524 * a second since last zap'd) then we zap it out (clear its bits.)
1526 * We hold off even calling zlc_setup, until after we've checked the
1527 * first zone in the zonelist, on the theory that most allocations will
1528 * be satisfied from that first zone, so best to examine that zone as
1529 * quickly as we can.
1531 static nodemask_t *zlc_setup(struct zonelist *zonelist, int alloc_flags)
1533 struct zonelist_cache *zlc; /* cached zonelist speedup info */
1534 nodemask_t *allowednodes; /* zonelist_cache approximation */
1536 zlc = zonelist->zlcache_ptr;
1540 if (time_after(jiffies, zlc->last_full_zap + HZ)) {
1541 bitmap_zero(zlc->fullzones, MAX_ZONES_PER_ZONELIST);
1542 zlc->last_full_zap = jiffies;
1545 allowednodes = !in_interrupt() && (alloc_flags & ALLOC_CPUSET) ?
1546 &cpuset_current_mems_allowed :
1547 &node_states[N_HIGH_MEMORY];
1548 return allowednodes;
1552 * Given 'z' scanning a zonelist, run a couple of quick checks to see
1553 * if it is worth looking at further for free memory:
1554 * 1) Check that the zone isn't thought to be full (doesn't have its
1555 * bit set in the zonelist_cache fullzones BITMAP).
1556 * 2) Check that the zones node (obtained from the zonelist_cache
1557 * z_to_n[] mapping) is allowed in the passed in allowednodes mask.
1558 * Return true (non-zero) if zone is worth looking at further, or
1559 * else return false (zero) if it is not.
1561 * This check -ignores- the distinction between various watermarks,
1562 * such as GFP_HIGH, GFP_ATOMIC, PF_MEMALLOC, ... If a zone is
1563 * found to be full for any variation of these watermarks, it will
1564 * be considered full for up to one second by all requests, unless
1565 * we are so low on memory on all allowed nodes that we are forced
1566 * into the second scan of the zonelist.
1568 * In the second scan we ignore this zonelist cache and exactly
1569 * apply the watermarks to all zones, even it is slower to do so.
1570 * We are low on memory in the second scan, and should leave no stone
1571 * unturned looking for a free page.
1573 static int zlc_zone_worth_trying(struct zonelist *zonelist, struct zoneref *z,
1574 nodemask_t *allowednodes)
1576 struct zonelist_cache *zlc; /* cached zonelist speedup info */
1577 int i; /* index of *z in zonelist zones */
1578 int n; /* node that zone *z is on */
1580 zlc = zonelist->zlcache_ptr;
1584 i = z - zonelist->_zonerefs;
1587 /* This zone is worth trying if it is allowed but not full */
1588 return node_isset(n, *allowednodes) && !test_bit(i, zlc->fullzones);
1592 * Given 'z' scanning a zonelist, set the corresponding bit in
1593 * zlc->fullzones, so that subsequent attempts to allocate a page
1594 * from that zone don't waste time re-examining it.
1596 static void zlc_mark_zone_full(struct zonelist *zonelist, struct zoneref *z)
1598 struct zonelist_cache *zlc; /* cached zonelist speedup info */
1599 int i; /* index of *z in zonelist zones */
1601 zlc = zonelist->zlcache_ptr;
1605 i = z - zonelist->_zonerefs;
1607 set_bit(i, zlc->fullzones);
1610 #else /* CONFIG_NUMA */
1612 static nodemask_t *zlc_setup(struct zonelist *zonelist, int alloc_flags)
1617 static int zlc_zone_worth_trying(struct zonelist *zonelist, struct zoneref *z,
1618 nodemask_t *allowednodes)
1623 static void zlc_mark_zone_full(struct zonelist *zonelist, struct zoneref *z)
1626 #endif /* CONFIG_NUMA */
1629 * get_page_from_freelist goes through the zonelist trying to allocate
1632 static struct page *
1633 get_page_from_freelist(gfp_t gfp_mask, nodemask_t *nodemask, unsigned int order,
1634 struct zonelist *zonelist, int high_zoneidx, int alloc_flags,
1635 struct zone *preferred_zone, int migratetype)
1638 struct page *page = NULL;
1641 nodemask_t *allowednodes = NULL;/* zonelist_cache approximation */
1642 int zlc_active = 0; /* set if using zonelist_cache */
1643 int did_zlc_setup = 0; /* just call zlc_setup() one time */
1645 classzone_idx = zone_idx(preferred_zone);
1648 * Scan zonelist, looking for a zone with enough free.
1649 * See also cpuset_zone_allowed() comment in kernel/cpuset.c.
1651 for_each_zone_zonelist_nodemask(zone, z, zonelist,
1652 high_zoneidx, nodemask) {
1653 if (NUMA_BUILD && zlc_active &&
1654 !zlc_zone_worth_trying(zonelist, z, allowednodes))
1656 if ((alloc_flags & ALLOC_CPUSET) &&
1657 !cpuset_zone_allowed_softwall(zone, gfp_mask))
1660 BUILD_BUG_ON(ALLOC_NO_WATERMARKS < NR_WMARK);
1661 if (!(alloc_flags & ALLOC_NO_WATERMARKS)) {
1665 mark = zone->watermark[alloc_flags & ALLOC_WMARK_MASK];
1666 if (zone_watermark_ok(zone, order, mark,
1667 classzone_idx, alloc_flags))
1670 if (zone_reclaim_mode == 0)
1671 goto this_zone_full;
1673 ret = zone_reclaim(zone, gfp_mask, order);
1675 case ZONE_RECLAIM_NOSCAN:
1678 case ZONE_RECLAIM_FULL:
1679 /* scanned but unreclaimable */
1680 goto this_zone_full;
1682 /* did we reclaim enough */
1683 if (!zone_watermark_ok(zone, order, mark,
1684 classzone_idx, alloc_flags))
1685 goto this_zone_full;
1690 page = buffered_rmqueue(preferred_zone, zone, order,
1691 gfp_mask, migratetype);
1696 zlc_mark_zone_full(zonelist, z);
1698 if (NUMA_BUILD && !did_zlc_setup && nr_online_nodes > 1) {
1700 * we do zlc_setup after the first zone is tried but only
1701 * if there are multiple nodes make it worthwhile
1703 allowednodes = zlc_setup(zonelist, alloc_flags);
1709 if (unlikely(NUMA_BUILD && page == NULL && zlc_active)) {
1710 /* Disable zlc cache for second zonelist scan */
1718 should_alloc_retry(gfp_t gfp_mask, unsigned int order,
1719 unsigned long pages_reclaimed)
1721 /* Do not loop if specifically requested */
1722 if (gfp_mask & __GFP_NORETRY)
1726 * In this implementation, order <= PAGE_ALLOC_COSTLY_ORDER
1727 * means __GFP_NOFAIL, but that may not be true in other
1730 if (order <= PAGE_ALLOC_COSTLY_ORDER)
1734 * For order > PAGE_ALLOC_COSTLY_ORDER, if __GFP_REPEAT is
1735 * specified, then we retry until we no longer reclaim any pages
1736 * (above), or we've reclaimed an order of pages at least as
1737 * large as the allocation's order. In both cases, if the
1738 * allocation still fails, we stop retrying.
1740 if (gfp_mask & __GFP_REPEAT && pages_reclaimed < (1 << order))
1744 * Don't let big-order allocations loop unless the caller
1745 * explicitly requests that.
1747 if (gfp_mask & __GFP_NOFAIL)
1753 static inline struct page *
1754 __alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order,
1755 struct zonelist *zonelist, enum zone_type high_zoneidx,
1756 nodemask_t *nodemask, struct zone *preferred_zone,
1761 /* Acquire the OOM killer lock for the zones in zonelist */
1762 if (!try_set_zonelist_oom(zonelist, gfp_mask)) {
1763 schedule_timeout_uninterruptible(1);
1768 * Go through the zonelist yet one more time, keep very high watermark
1769 * here, this is only to catch a parallel oom killing, we must fail if
1770 * we're still under heavy pressure.
1772 page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask,
1773 order, zonelist, high_zoneidx,
1774 ALLOC_WMARK_HIGH|ALLOC_CPUSET,
1775 preferred_zone, migratetype);
1779 if (!(gfp_mask & __GFP_NOFAIL)) {
1780 /* The OOM killer will not help higher order allocs */
1781 if (order > PAGE_ALLOC_COSTLY_ORDER)
1783 /* The OOM killer does not needlessly kill tasks for lowmem */
1784 if (high_zoneidx < ZONE_NORMAL)
1787 * GFP_THISNODE contains __GFP_NORETRY and we never hit this.
1788 * Sanity check for bare calls of __GFP_THISNODE, not real OOM.
1789 * The caller should handle page allocation failure by itself if
1790 * it specifies __GFP_THISNODE.
1791 * Note: Hugepage uses it but will hit PAGE_ALLOC_COSTLY_ORDER.
1793 if (gfp_mask & __GFP_THISNODE)
1796 /* Exhausted what can be done so it's blamo time */
1797 out_of_memory(zonelist, gfp_mask, order, nodemask);
1800 clear_zonelist_oom(zonelist, gfp_mask);
1804 #ifdef CONFIG_COMPACTION
1805 /* Try memory compaction for high-order allocations before reclaim */
1806 static struct page *
1807 __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order,
1808 struct zonelist *zonelist, enum zone_type high_zoneidx,
1809 nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone,
1810 int migratetype, unsigned long *did_some_progress,
1811 bool sync_migration)
1815 if (!order || compaction_deferred(preferred_zone))
1818 current->flags |= PF_MEMALLOC;
1819 *did_some_progress = try_to_compact_pages(zonelist, order, gfp_mask,
1820 nodemask, sync_migration);
1821 current->flags &= ~PF_MEMALLOC;
1822 if (*did_some_progress != COMPACT_SKIPPED) {
1824 /* Page migration frees to the PCP lists but we want merging */
1825 drain_pages(get_cpu());
1828 page = get_page_from_freelist(gfp_mask, nodemask,
1829 order, zonelist, high_zoneidx,
1830 alloc_flags, preferred_zone,
1833 preferred_zone->compact_considered = 0;
1834 preferred_zone->compact_defer_shift = 0;
1835 count_vm_event(COMPACTSUCCESS);
1840 * It's bad if compaction run occurs and fails.
1841 * The most likely reason is that pages exist,
1842 * but not enough to satisfy watermarks.
1844 count_vm_event(COMPACTFAIL);
1845 defer_compaction(preferred_zone);
1853 static inline struct page *
1854 __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order,
1855 struct zonelist *zonelist, enum zone_type high_zoneidx,
1856 nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone,
1857 int migratetype, unsigned long *did_some_progress,
1858 bool sync_migration)
1862 #endif /* CONFIG_COMPACTION */
1864 /* The really slow allocator path where we enter direct reclaim */
1865 static inline struct page *
1866 __alloc_pages_direct_reclaim(gfp_t gfp_mask, unsigned int order,
1867 struct zonelist *zonelist, enum zone_type high_zoneidx,
1868 nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone,
1869 int migratetype, unsigned long *did_some_progress)
1871 struct page *page = NULL;
1872 struct reclaim_state reclaim_state;
1873 bool drained = false;
1877 /* We now go into synchronous reclaim */
1878 cpuset_memory_pressure_bump();
1879 current->flags |= PF_MEMALLOC;
1880 lockdep_set_current_reclaim_state(gfp_mask);
1881 reclaim_state.reclaimed_slab = 0;
1882 current->reclaim_state = &reclaim_state;
1884 *did_some_progress = try_to_free_pages(zonelist, order, gfp_mask, nodemask);
1886 current->reclaim_state = NULL;
1887 lockdep_clear_current_reclaim_state();
1888 current->flags &= ~PF_MEMALLOC;
1892 if (unlikely(!(*did_some_progress)))
1896 page = get_page_from_freelist(gfp_mask, nodemask, order,
1897 zonelist, high_zoneidx,
1898 alloc_flags, preferred_zone,
1902 * If an allocation failed after direct reclaim, it could be because
1903 * pages are pinned on the per-cpu lists. Drain them and try again
1905 if (!page && !drained) {
1915 * This is called in the allocator slow-path if the allocation request is of
1916 * sufficient urgency to ignore watermarks and take other desperate measures
1918 static inline struct page *
1919 __alloc_pages_high_priority(gfp_t gfp_mask, unsigned int order,
1920 struct zonelist *zonelist, enum zone_type high_zoneidx,
1921 nodemask_t *nodemask, struct zone *preferred_zone,
1927 page = get_page_from_freelist(gfp_mask, nodemask, order,
1928 zonelist, high_zoneidx, ALLOC_NO_WATERMARKS,
1929 preferred_zone, migratetype);
1931 if (!page && gfp_mask & __GFP_NOFAIL)
1932 wait_iff_congested(preferred_zone, BLK_RW_ASYNC, HZ/50);
1933 } while (!page && (gfp_mask & __GFP_NOFAIL));
1939 void wake_all_kswapd(unsigned int order, struct zonelist *zonelist,
1940 enum zone_type high_zoneidx,
1941 enum zone_type classzone_idx)
1946 for_each_zone_zonelist(zone, z, zonelist, high_zoneidx)
1947 wakeup_kswapd(zone, order, classzone_idx);
1951 gfp_to_alloc_flags(gfp_t gfp_mask)
1953 int alloc_flags = ALLOC_WMARK_MIN | ALLOC_CPUSET;
1954 const gfp_t wait = gfp_mask & __GFP_WAIT;
1956 /* __GFP_HIGH is assumed to be the same as ALLOC_HIGH to save a branch. */
1957 BUILD_BUG_ON(__GFP_HIGH != (__force gfp_t) ALLOC_HIGH);
1960 * The caller may dip into page reserves a bit more if the caller
1961 * cannot run direct reclaim, or if the caller has realtime scheduling
1962 * policy or is asking for __GFP_HIGH memory. GFP_ATOMIC requests will
1963 * set both ALLOC_HARDER (!wait) and ALLOC_HIGH (__GFP_HIGH).
1965 alloc_flags |= (__force int) (gfp_mask & __GFP_HIGH);
1969 * Not worth trying to allocate harder for
1970 * __GFP_NOMEMALLOC even if it can't schedule.
1972 if (!(gfp_mask & __GFP_NOMEMALLOC))
1973 alloc_flags |= ALLOC_HARDER;
1975 * Ignore cpuset if GFP_ATOMIC (!wait) rather than fail alloc.
1976 * See also cpuset_zone_allowed() comment in kernel/cpuset.c.
1978 alloc_flags &= ~ALLOC_CPUSET;
1979 } else if (unlikely(rt_task(current)) && !in_interrupt())
1980 alloc_flags |= ALLOC_HARDER;
1982 if (likely(!(gfp_mask & __GFP_NOMEMALLOC))) {
1983 if (!in_interrupt() &&
1984 ((current->flags & PF_MEMALLOC) ||
1985 unlikely(test_thread_flag(TIF_MEMDIE))))
1986 alloc_flags |= ALLOC_NO_WATERMARKS;
1992 static inline struct page *
1993 __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order,
1994 struct zonelist *zonelist, enum zone_type high_zoneidx,
1995 nodemask_t *nodemask, struct zone *preferred_zone,
1998 const gfp_t wait = gfp_mask & __GFP_WAIT;
1999 struct page *page = NULL;
2001 unsigned long pages_reclaimed = 0;
2002 unsigned long did_some_progress;
2003 bool sync_migration = false;
2006 * In the slowpath, we sanity check order to avoid ever trying to
2007 * reclaim >= MAX_ORDER areas which will never succeed. Callers may
2008 * be using allocators in order of preference for an area that is
2011 if (order >= MAX_ORDER) {
2012 WARN_ON_ONCE(!(gfp_mask & __GFP_NOWARN));
2017 * GFP_THISNODE (meaning __GFP_THISNODE, __GFP_NORETRY and
2018 * __GFP_NOWARN set) should not cause reclaim since the subsystem
2019 * (f.e. slab) using GFP_THISNODE may choose to trigger reclaim
2020 * using a larger set of nodes after it has established that the
2021 * allowed per node queues are empty and that nodes are
2024 if (NUMA_BUILD && (gfp_mask & GFP_THISNODE) == GFP_THISNODE)
2028 if (!(gfp_mask & __GFP_NO_KSWAPD))
2029 wake_all_kswapd(order, zonelist, high_zoneidx,
2030 zone_idx(preferred_zone));
2033 * OK, we're below the kswapd watermark and have kicked background
2034 * reclaim. Now things get more complex, so set up alloc_flags according
2035 * to how we want to proceed.
2037 alloc_flags = gfp_to_alloc_flags(gfp_mask);
2040 * Find the true preferred zone if the allocation is unconstrained by
2043 if (!(alloc_flags & ALLOC_CPUSET) && !nodemask)
2044 first_zones_zonelist(zonelist, high_zoneidx, NULL,
2047 /* This is the last chance, in general, before the goto nopage. */
2048 page = get_page_from_freelist(gfp_mask, nodemask, order, zonelist,
2049 high_zoneidx, alloc_flags & ~ALLOC_NO_WATERMARKS,
2050 preferred_zone, migratetype);
2055 /* Allocate without watermarks if the context allows */
2056 if (alloc_flags & ALLOC_NO_WATERMARKS) {
2057 page = __alloc_pages_high_priority(gfp_mask, order,
2058 zonelist, high_zoneidx, nodemask,
2059 preferred_zone, migratetype);
2064 /* Atomic allocations - we can't balance anything */
2068 /* Avoid recursion of direct reclaim */
2069 if (current->flags & PF_MEMALLOC)
2072 /* Avoid allocations with no watermarks from looping endlessly */
2073 if (test_thread_flag(TIF_MEMDIE) && !(gfp_mask & __GFP_NOFAIL))
2077 * Try direct compaction. The first pass is asynchronous. Subsequent
2078 * attempts after direct reclaim are synchronous
2080 page = __alloc_pages_direct_compact(gfp_mask, order,
2081 zonelist, high_zoneidx,
2083 alloc_flags, preferred_zone,
2084 migratetype, &did_some_progress,
2088 sync_migration = true;
2090 /* Try direct reclaim and then allocating */
2091 page = __alloc_pages_direct_reclaim(gfp_mask, order,
2092 zonelist, high_zoneidx,
2094 alloc_flags, preferred_zone,
2095 migratetype, &did_some_progress);
2100 * If we failed to make any progress reclaiming, then we are
2101 * running out of options and have to consider going OOM
2103 if (!did_some_progress) {
2104 if ((gfp_mask & __GFP_FS) && !(gfp_mask & __GFP_NORETRY)) {
2105 if (oom_killer_disabled)
2107 page = __alloc_pages_may_oom(gfp_mask, order,
2108 zonelist, high_zoneidx,
2109 nodemask, preferred_zone,
2114 if (!(gfp_mask & __GFP_NOFAIL)) {
2116 * The oom killer is not called for high-order
2117 * allocations that may fail, so if no progress
2118 * is being made, there are no other options and
2119 * retrying is unlikely to help.
2121 if (order > PAGE_ALLOC_COSTLY_ORDER)
2124 * The oom killer is not called for lowmem
2125 * allocations to prevent needlessly killing
2128 if (high_zoneidx < ZONE_NORMAL)
2136 /* Check if we should retry the allocation */
2137 pages_reclaimed += did_some_progress;
2138 if (should_alloc_retry(gfp_mask, order, pages_reclaimed)) {
2139 /* Wait for some write requests to complete then retry */
2140 wait_iff_congested(preferred_zone, BLK_RW_ASYNC, HZ/50);
2144 * High-order allocations do not necessarily loop after
2145 * direct reclaim and reclaim/compaction depends on compaction
2146 * being called after reclaim so call directly if necessary
2148 page = __alloc_pages_direct_compact(gfp_mask, order,
2149 zonelist, high_zoneidx,
2151 alloc_flags, preferred_zone,
2152 migratetype, &did_some_progress,
2159 if (!(gfp_mask & __GFP_NOWARN) && printk_ratelimit()) {
2160 printk(KERN_WARNING "%s: page allocation failure."
2161 " order:%d, mode:0x%x\n",
2162 current->comm, order, gfp_mask);
2168 if (kmemcheck_enabled)
2169 kmemcheck_pagealloc_alloc(page, order, gfp_mask);
2175 * This is the 'heart' of the zoned buddy allocator.
2178 __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
2179 struct zonelist *zonelist, nodemask_t *nodemask)
2181 enum zone_type high_zoneidx = gfp_zone(gfp_mask);
2182 struct zone *preferred_zone;
2184 int migratetype = allocflags_to_migratetype(gfp_mask);
2186 gfp_mask &= gfp_allowed_mask;
2188 lockdep_trace_alloc(gfp_mask);
2190 might_sleep_if(gfp_mask & __GFP_WAIT);
2192 if (should_fail_alloc_page(gfp_mask, order))
2196 * Check the zones suitable for the gfp_mask contain at least one
2197 * valid zone. It's possible to have an empty zonelist as a result
2198 * of GFP_THISNODE and a memoryless node
2200 if (unlikely(!zonelist->_zonerefs->zone))
2204 /* The preferred zone is used for statistics later */
2205 first_zones_zonelist(zonelist, high_zoneidx,
2206 nodemask ? : &cpuset_current_mems_allowed,
2208 if (!preferred_zone) {
2213 /* First allocation attempt */
2214 page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask, order,
2215 zonelist, high_zoneidx, ALLOC_WMARK_LOW|ALLOC_CPUSET,
2216 preferred_zone, migratetype);
2217 if (unlikely(!page))
2218 page = __alloc_pages_slowpath(gfp_mask, order,
2219 zonelist, high_zoneidx, nodemask,
2220 preferred_zone, migratetype);
2223 trace_mm_page_alloc(page, order, gfp_mask, migratetype);
2226 EXPORT_SYMBOL(__alloc_pages_nodemask);
2229 * Common helper functions.
2231 unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order)
2236 * __get_free_pages() returns a 32-bit address, which cannot represent
2239 VM_BUG_ON((gfp_mask & __GFP_HIGHMEM) != 0);
2241 page = alloc_pages(gfp_mask, order);
2244 return (unsigned long) page_address(page);
2246 EXPORT_SYMBOL(__get_free_pages);
2248 unsigned long get_zeroed_page(gfp_t gfp_mask)
2250 return __get_free_pages(gfp_mask | __GFP_ZERO, 0);
2252 EXPORT_SYMBOL(get_zeroed_page);
2254 void __pagevec_free(struct pagevec *pvec)
2256 int i = pagevec_count(pvec);
2259 trace_mm_pagevec_free(pvec->pages[i], pvec->cold);
2260 free_hot_cold_page(pvec->pages[i], pvec->cold);
2264 void __free_pages(struct page *page, unsigned int order)
2266 if (put_page_testzero(page)) {
2268 free_hot_cold_page(page, 0);
2270 __free_pages_ok(page, order);
2274 EXPORT_SYMBOL(__free_pages);
2276 void free_pages(unsigned long addr, unsigned int order)
2279 VM_BUG_ON(!virt_addr_valid((void *)addr));
2280 __free_pages(virt_to_page((void *)addr), order);
2284 EXPORT_SYMBOL(free_pages);
2287 * alloc_pages_exact - allocate an exact number physically-contiguous pages.
2288 * @size: the number of bytes to allocate
2289 * @gfp_mask: GFP flags for the allocation
2291 * This function is similar to alloc_pages(), except that it allocates the
2292 * minimum number of pages to satisfy the request. alloc_pages() can only
2293 * allocate memory in power-of-two pages.
2295 * This function is also limited by MAX_ORDER.
2297 * Memory allocated by this function must be released by free_pages_exact().
2299 void *alloc_pages_exact(size_t size, gfp_t gfp_mask)
2301 unsigned int order = get_order(size);
2304 addr = __get_free_pages(gfp_mask, order);
2306 unsigned long alloc_end = addr + (PAGE_SIZE << order);
2307 unsigned long used = addr + PAGE_ALIGN(size);
2309 split_page(virt_to_page((void *)addr), order);
2310 while (used < alloc_end) {
2316 return (void *)addr;
2318 EXPORT_SYMBOL(alloc_pages_exact);
2321 * free_pages_exact - release memory allocated via alloc_pages_exact()
2322 * @virt: the value returned by alloc_pages_exact.
2323 * @size: size of allocation, same value as passed to alloc_pages_exact().
2325 * Release the memory allocated by a previous call to alloc_pages_exact.
2327 void free_pages_exact(void *virt, size_t size)
2329 unsigned long addr = (unsigned long)virt;
2330 unsigned long end = addr + PAGE_ALIGN(size);
2332 while (addr < end) {
2337 EXPORT_SYMBOL(free_pages_exact);
2339 static unsigned int nr_free_zone_pages(int offset)
2344 /* Just pick one node, since fallback list is circular */
2345 unsigned int sum = 0;
2347 struct zonelist *zonelist = node_zonelist(numa_node_id(), GFP_KERNEL);
2349 for_each_zone_zonelist(zone, z, zonelist, offset) {
2350 unsigned long size = zone->present_pages;
2351 unsigned long high = high_wmark_pages(zone);
2360 * Amount of free RAM allocatable within ZONE_DMA and ZONE_NORMAL
2362 unsigned int nr_free_buffer_pages(void)
2364 return nr_free_zone_pages(gfp_zone(GFP_USER));
2366 EXPORT_SYMBOL_GPL(nr_free_buffer_pages);
2369 * Amount of free RAM allocatable within all zones
2371 unsigned int nr_free_pagecache_pages(void)
2373 return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE));
2376 static inline void show_node(struct zone *zone)
2379 printk("Node %d ", zone_to_nid(zone));
2382 void si_meminfo(struct sysinfo *val)
2384 val->totalram = totalram_pages;
2386 val->freeram = global_page_state(NR_FREE_PAGES);
2387 val->bufferram = nr_blockdev_pages();
2388 val->totalhigh = totalhigh_pages;
2389 val->freehigh = nr_free_highpages();
2390 val->mem_unit = PAGE_SIZE;
2393 EXPORT_SYMBOL(si_meminfo);
2396 void si_meminfo_node(struct sysinfo *val, int nid)
2398 pg_data_t *pgdat = NODE_DATA(nid);
2400 val->totalram = pgdat->node_present_pages;
2401 val->freeram = node_page_state(nid, NR_FREE_PAGES);
2402 #ifdef CONFIG_HIGHMEM
2403 val->totalhigh = pgdat->node_zones[ZONE_HIGHMEM].present_pages;
2404 val->freehigh = zone_page_state(&pgdat->node_zones[ZONE_HIGHMEM],
2410 val->mem_unit = PAGE_SIZE;
2415 * Determine whether the zone's node should be displayed or not, depending on
2416 * whether SHOW_MEM_FILTER_NODES was passed to __show_free_areas().
2418 static bool skip_free_areas_zone(unsigned int flags, const struct zone *zone)
2422 if (!(flags & SHOW_MEM_FILTER_NODES))
2426 ret = !node_isset(zone->zone_pgdat->node_id,
2427 cpuset_current_mems_allowed);
2433 #define K(x) ((x) << (PAGE_SHIFT-10))
2436 * Show free area list (used inside shift_scroll-lock stuff)
2437 * We also calculate the percentage fragmentation. We do this by counting the
2438 * memory on each free list with the exception of the first item on the list.
2439 * Suppresses nodes that are not allowed by current's cpuset if
2440 * SHOW_MEM_FILTER_NODES is passed.
2442 void __show_free_areas(unsigned int filter)
2447 for_each_populated_zone(zone) {
2448 if (skip_free_areas_zone(filter, zone))
2451 printk("%s per-cpu:\n", zone->name);
2453 for_each_online_cpu(cpu) {
2454 struct per_cpu_pageset *pageset;
2456 pageset = per_cpu_ptr(zone->pageset, cpu);
2458 printk("CPU %4d: hi:%5d, btch:%4d usd:%4d\n",
2459 cpu, pageset->pcp.high,
2460 pageset->pcp.batch, pageset->pcp.count);
2464 printk("active_anon:%lu inactive_anon:%lu isolated_anon:%lu\n"
2465 " active_file:%lu inactive_file:%lu isolated_file:%lu\n"
2467 " dirty:%lu writeback:%lu unstable:%lu\n"
2468 " free:%lu slab_reclaimable:%lu slab_unreclaimable:%lu\n"
2469 " mapped:%lu shmem:%lu pagetables:%lu bounce:%lu\n",
2470 global_page_state(NR_ACTIVE_ANON),
2471 global_page_state(NR_INACTIVE_ANON),
2472 global_page_state(NR_ISOLATED_ANON),
2473 global_page_state(NR_ACTIVE_FILE),
2474 global_page_state(NR_INACTIVE_FILE),
2475 global_page_state(NR_ISOLATED_FILE),
2476 global_page_state(NR_UNEVICTABLE),
2477 global_page_state(NR_FILE_DIRTY),
2478 global_page_state(NR_WRITEBACK),
2479 global_page_state(NR_UNSTABLE_NFS),
2480 global_page_state(NR_FREE_PAGES),
2481 global_page_state(NR_SLAB_RECLAIMABLE),
2482 global_page_state(NR_SLAB_UNRECLAIMABLE),
2483 global_page_state(NR_FILE_MAPPED),
2484 global_page_state(NR_SHMEM),
2485 global_page_state(NR_PAGETABLE),
2486 global_page_state(NR_BOUNCE));
2488 for_each_populated_zone(zone) {
2491 if (skip_free_areas_zone(filter, zone))
2499 " active_anon:%lukB"
2500 " inactive_anon:%lukB"
2501 " active_file:%lukB"
2502 " inactive_file:%lukB"
2503 " unevictable:%lukB"
2504 " isolated(anon):%lukB"
2505 " isolated(file):%lukB"
2512 " slab_reclaimable:%lukB"
2513 " slab_unreclaimable:%lukB"
2514 " kernel_stack:%lukB"
2518 " writeback_tmp:%lukB"
2519 " pages_scanned:%lu"
2520 " all_unreclaimable? %s"
2523 K(zone_page_state(zone, NR_FREE_PAGES)),
2524 K(min_wmark_pages(zone)),
2525 K(low_wmark_pages(zone)),
2526 K(high_wmark_pages(zone)),
2527 K(zone_page_state(zone, NR_ACTIVE_ANON)),
2528 K(zone_page_state(zone, NR_INACTIVE_ANON)),
2529 K(zone_page_state(zone, NR_ACTIVE_FILE)),
2530 K(zone_page_state(zone, NR_INACTIVE_FILE)),
2531 K(zone_page_state(zone, NR_UNEVICTABLE)),
2532 K(zone_page_state(zone, NR_ISOLATED_ANON)),
2533 K(zone_page_state(zone, NR_ISOLATED_FILE)),
2534 K(zone->present_pages),
2535 K(zone_page_state(zone, NR_MLOCK)),
2536 K(zone_page_state(zone, NR_FILE_DIRTY)),
2537 K(zone_page_state(zone, NR_WRITEBACK)),
2538 K(zone_page_state(zone, NR_FILE_MAPPED)),
2539 K(zone_page_state(zone, NR_SHMEM)),
2540 K(zone_page_state(zone, NR_SLAB_RECLAIMABLE)),
2541 K(zone_page_state(zone, NR_SLAB_UNRECLAIMABLE)),
2542 zone_page_state(zone, NR_KERNEL_STACK) *
2544 K(zone_page_state(zone, NR_PAGETABLE)),
2545 K(zone_page_state(zone, NR_UNSTABLE_NFS)),
2546 K(zone_page_state(zone, NR_BOUNCE)),
2547 K(zone_page_state(zone, NR_WRITEBACK_TEMP)),
2548 zone->pages_scanned,
2549 (zone->all_unreclaimable ? "yes" : "no")
2551 printk("lowmem_reserve[]:");
2552 for (i = 0; i < MAX_NR_ZONES; i++)
2553 printk(" %lu", zone->lowmem_reserve[i]);
2557 for_each_populated_zone(zone) {
2558 unsigned long nr[MAX_ORDER], flags, order, total = 0;
2560 if (skip_free_areas_zone(filter, zone))
2563 printk("%s: ", zone->name);
2565 spin_lock_irqsave(&zone->lock, flags);
2566 for (order = 0; order < MAX_ORDER; order++) {
2567 nr[order] = zone->free_area[order].nr_free;
2568 total += nr[order] << order;
2570 spin_unlock_irqrestore(&zone->lock, flags);
2571 for (order = 0; order < MAX_ORDER; order++)
2572 printk("%lu*%lukB ", nr[order], K(1UL) << order);
2573 printk("= %lukB\n", K(total));
2576 printk("%ld total pagecache pages\n", global_page_state(NR_FILE_PAGES));
2578 show_swap_cache_info();
2581 void show_free_areas(void)
2583 __show_free_areas(0);
2586 static void zoneref_set_zone(struct zone *zone, struct zoneref *zoneref)
2588 zoneref->zone = zone;
2589 zoneref->zone_idx = zone_idx(zone);
2593 * Builds allocation fallback zone lists.
2595 * Add all populated zones of a node to the zonelist.
2597 static int build_zonelists_node(pg_data_t *pgdat, struct zonelist *zonelist,
2598 int nr_zones, enum zone_type zone_type)
2602 BUG_ON(zone_type >= MAX_NR_ZONES);
2607 zone = pgdat->node_zones + zone_type;
2608 if (populated_zone(zone)) {
2609 zoneref_set_zone(zone,
2610 &zonelist->_zonerefs[nr_zones++]);
2611 check_highest_zone(zone_type);
2614 } while (zone_type);
2621 * 0 = automatic detection of better ordering.
2622 * 1 = order by ([node] distance, -zonetype)
2623 * 2 = order by (-zonetype, [node] distance)
2625 * If not NUMA, ZONELIST_ORDER_ZONE and ZONELIST_ORDER_NODE will create
2626 * the same zonelist. So only NUMA can configure this param.
2628 #define ZONELIST_ORDER_DEFAULT 0
2629 #define ZONELIST_ORDER_NODE 1
2630 #define ZONELIST_ORDER_ZONE 2
2632 /* zonelist order in the kernel.
2633 * set_zonelist_order() will set this to NODE or ZONE.
2635 static int current_zonelist_order = ZONELIST_ORDER_DEFAULT;
2636 static char zonelist_order_name[3][8] = {"Default", "Node", "Zone"};
2640 /* The value user specified ....changed by config */
2641 static int user_zonelist_order = ZONELIST_ORDER_DEFAULT;
2642 /* string for sysctl */
2643 #define NUMA_ZONELIST_ORDER_LEN 16
2644 char numa_zonelist_order[16] = "default";
2647 * interface for configure zonelist ordering.
2648 * command line option "numa_zonelist_order"
2649 * = "[dD]efault - default, automatic configuration.
2650 * = "[nN]ode - order by node locality, then by zone within node
2651 * = "[zZ]one - order by zone, then by locality within zone
2654 static int __parse_numa_zonelist_order(char *s)
2656 if (*s == 'd' || *s == 'D') {
2657 user_zonelist_order = ZONELIST_ORDER_DEFAULT;
2658 } else if (*s == 'n' || *s == 'N') {
2659 user_zonelist_order = ZONELIST_ORDER_NODE;
2660 } else if (*s == 'z' || *s == 'Z') {
2661 user_zonelist_order = ZONELIST_ORDER_ZONE;
2664 "Ignoring invalid numa_zonelist_order value: "
2671 static __init int setup_numa_zonelist_order(char *s)
2678 ret = __parse_numa_zonelist_order(s);
2680 strlcpy(numa_zonelist_order, s, NUMA_ZONELIST_ORDER_LEN);
2684 early_param("numa_zonelist_order", setup_numa_zonelist_order);
2687 * sysctl handler for numa_zonelist_order
2689 int numa_zonelist_order_handler(ctl_table *table, int write,
2690 void __user *buffer, size_t *length,
2693 char saved_string[NUMA_ZONELIST_ORDER_LEN];
2695 static DEFINE_MUTEX(zl_order_mutex);
2697 mutex_lock(&zl_order_mutex);
2699 strcpy(saved_string, (char*)table->data);
2700 ret = proc_dostring(table, write, buffer, length, ppos);
2704 int oldval = user_zonelist_order;
2705 if (__parse_numa_zonelist_order((char*)table->data)) {
2707 * bogus value. restore saved string
2709 strncpy((char*)table->data, saved_string,
2710 NUMA_ZONELIST_ORDER_LEN);
2711 user_zonelist_order = oldval;
2712 } else if (oldval != user_zonelist_order) {
2713 mutex_lock(&zonelists_mutex);
2714 build_all_zonelists(NULL);
2715 mutex_unlock(&zonelists_mutex);
2719 mutex_unlock(&zl_order_mutex);
2724 #define MAX_NODE_LOAD (nr_online_nodes)
2725 static int node_load[MAX_NUMNODES];
2728 * find_next_best_node - find the next node that should appear in a given node's fallback list
2729 * @node: node whose fallback list we're appending
2730 * @used_node_mask: nodemask_t of already used nodes
2732 * We use a number of factors to determine which is the next node that should
2733 * appear on a given node's fallback list. The node should not have appeared
2734 * already in @node's fallback list, and it should be the next closest node
2735 * according to the distance array (which contains arbitrary distance values
2736 * from each node to each node in the system), and should also prefer nodes
2737 * with no CPUs, since presumably they'll have very little allocation pressure
2738 * on them otherwise.
2739 * It returns -1 if no node is found.
2741 static int find_next_best_node(int node, nodemask_t *used_node_mask)
2744 int min_val = INT_MAX;
2746 const struct cpumask *tmp = cpumask_of_node(0);
2748 /* Use the local node if we haven't already */
2749 if (!node_isset(node, *used_node_mask)) {
2750 node_set(node, *used_node_mask);
2754 for_each_node_state(n, N_HIGH_MEMORY) {
2756 /* Don't want a node to appear more than once */
2757 if (node_isset(n, *used_node_mask))
2760 /* Use the distance array to find the distance */
2761 val = node_distance(node, n);
2763 /* Penalize nodes under us ("prefer the next node") */
2766 /* Give preference to headless and unused nodes */
2767 tmp = cpumask_of_node(n);
2768 if (!cpumask_empty(tmp))
2769 val += PENALTY_FOR_NODE_WITH_CPUS;
2771 /* Slight preference for less loaded node */
2772 val *= (MAX_NODE_LOAD*MAX_NUMNODES);
2773 val += node_load[n];
2775 if (val < min_val) {
2782 node_set(best_node, *used_node_mask);
2789 * Build zonelists ordered by node and zones within node.
2790 * This results in maximum locality--normal zone overflows into local
2791 * DMA zone, if any--but risks exhausting DMA zone.
2793 static void build_zonelists_in_node_order(pg_data_t *pgdat, int node)
2796 struct zonelist *zonelist;
2798 zonelist = &pgdat->node_zonelists[0];
2799 for (j = 0; zonelist->_zonerefs[j].zone != NULL; j++)
2801 j = build_zonelists_node(NODE_DATA(node), zonelist, j,
2803 zonelist->_zonerefs[j].zone = NULL;
2804 zonelist->_zonerefs[j].zone_idx = 0;
2808 * Build gfp_thisnode zonelists
2810 static void build_thisnode_zonelists(pg_data_t *pgdat)
2813 struct zonelist *zonelist;
2815 zonelist = &pgdat->node_zonelists[1];
2816 j = build_zonelists_node(pgdat, zonelist, 0, MAX_NR_ZONES - 1);
2817 zonelist->_zonerefs[j].zone = NULL;
2818 zonelist->_zonerefs[j].zone_idx = 0;
2822 * Build zonelists ordered by zone and nodes within zones.
2823 * This results in conserving DMA zone[s] until all Normal memory is
2824 * exhausted, but results in overflowing to remote node while memory
2825 * may still exist in local DMA zone.
2827 static int node_order[MAX_NUMNODES];
2829 static void build_zonelists_in_zone_order(pg_data_t *pgdat, int nr_nodes)
2832 int zone_type; /* needs to be signed */
2834 struct zonelist *zonelist;
2836 zonelist = &pgdat->node_zonelists[0];
2838 for (zone_type = MAX_NR_ZONES - 1; zone_type >= 0; zone_type--) {
2839 for (j = 0; j < nr_nodes; j++) {
2840 node = node_order[j];
2841 z = &NODE_DATA(node)->node_zones[zone_type];
2842 if (populated_zone(z)) {
2844 &zonelist->_zonerefs[pos++]);
2845 check_highest_zone(zone_type);
2849 zonelist->_zonerefs[pos].zone = NULL;
2850 zonelist->_zonerefs[pos].zone_idx = 0;
2853 static int default_zonelist_order(void)
2856 unsigned long low_kmem_size,total_size;
2860 * ZONE_DMA and ZONE_DMA32 can be very small area in the system.
2861 * If they are really small and used heavily, the system can fall
2862 * into OOM very easily.
2863 * This function detect ZONE_DMA/DMA32 size and configures zone order.
2865 /* Is there ZONE_NORMAL ? (ex. ppc has only DMA zone..) */
2868 for_each_online_node(nid) {
2869 for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++) {
2870 z = &NODE_DATA(nid)->node_zones[zone_type];
2871 if (populated_zone(z)) {
2872 if (zone_type < ZONE_NORMAL)
2873 low_kmem_size += z->present_pages;
2874 total_size += z->present_pages;
2875 } else if (zone_type == ZONE_NORMAL) {
2877 * If any node has only lowmem, then node order
2878 * is preferred to allow kernel allocations
2879 * locally; otherwise, they can easily infringe
2880 * on other nodes when there is an abundance of
2881 * lowmem available to allocate from.
2883 return ZONELIST_ORDER_NODE;
2887 if (!low_kmem_size || /* there are no DMA area. */
2888 low_kmem_size > total_size/2) /* DMA/DMA32 is big. */
2889 return ZONELIST_ORDER_NODE;
2891 * look into each node's config.
2892 * If there is a node whose DMA/DMA32 memory is very big area on
2893 * local memory, NODE_ORDER may be suitable.
2895 average_size = total_size /
2896 (nodes_weight(node_states[N_HIGH_MEMORY]) + 1);
2897 for_each_online_node(nid) {
2900 for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++) {
2901 z = &NODE_DATA(nid)->node_zones[zone_type];
2902 if (populated_zone(z)) {
2903 if (zone_type < ZONE_NORMAL)
2904 low_kmem_size += z->present_pages;
2905 total_size += z->present_pages;
2908 if (low_kmem_size &&
2909 total_size > average_size && /* ignore small node */
2910 low_kmem_size > total_size * 70/100)
2911 return ZONELIST_ORDER_NODE;
2913 return ZONELIST_ORDER_ZONE;
2916 static void set_zonelist_order(void)
2918 if (user_zonelist_order == ZONELIST_ORDER_DEFAULT)
2919 current_zonelist_order = default_zonelist_order();
2921 current_zonelist_order = user_zonelist_order;
2924 static void build_zonelists(pg_data_t *pgdat)
2928 nodemask_t used_mask;
2929 int local_node, prev_node;
2930 struct zonelist *zonelist;
2931 int order = current_zonelist_order;
2933 /* initialize zonelists */
2934 for (i = 0; i < MAX_ZONELISTS; i++) {
2935 zonelist = pgdat->node_zonelists + i;
2936 zonelist->_zonerefs[0].zone = NULL;
2937 zonelist->_zonerefs[0].zone_idx = 0;
2940 /* NUMA-aware ordering of nodes */
2941 local_node = pgdat->node_id;
2942 load = nr_online_nodes;
2943 prev_node = local_node;
2944 nodes_clear(used_mask);
2946 memset(node_order, 0, sizeof(node_order));
2949 while ((node = find_next_best_node(local_node, &used_mask)) >= 0) {
2950 int distance = node_distance(local_node, node);
2953 * If another node is sufficiently far away then it is better
2954 * to reclaim pages in a zone before going off node.
2956 if (distance > RECLAIM_DISTANCE)
2957 zone_reclaim_mode = 1;
2960 * We don't want to pressure a particular node.
2961 * So adding penalty to the first node in same
2962 * distance group to make it round-robin.
2964 if (distance != node_distance(local_node, prev_node))
2965 node_load[node] = load;
2969 if (order == ZONELIST_ORDER_NODE)
2970 build_zonelists_in_node_order(pgdat, node);
2972 node_order[j++] = node; /* remember order */
2975 if (order == ZONELIST_ORDER_ZONE) {
2976 /* calculate node order -- i.e., DMA last! */
2977 build_zonelists_in_zone_order(pgdat, j);
2980 build_thisnode_zonelists(pgdat);
2983 /* Construct the zonelist performance cache - see further mmzone.h */
2984 static void build_zonelist_cache(pg_data_t *pgdat)
2986 struct zonelist *zonelist;
2987 struct zonelist_cache *zlc;
2990 zonelist = &pgdat->node_zonelists[0];
2991 zonelist->zlcache_ptr = zlc = &zonelist->zlcache;
2992 bitmap_zero(zlc->fullzones, MAX_ZONES_PER_ZONELIST);
2993 for (z = zonelist->_zonerefs; z->zone; z++)
2994 zlc->z_to_n[z - zonelist->_zonerefs] = zonelist_node_idx(z);
2997 #ifdef CONFIG_HAVE_MEMORYLESS_NODES
2999 * Return node id of node used for "local" allocations.
3000 * I.e., first node id of first zone in arg node's generic zonelist.
3001 * Used for initializing percpu 'numa_mem', which is used primarily
3002 * for kernel allocations, so use GFP_KERNEL flags to locate zonelist.
3004 int local_memory_node(int node)
3008 (void)first_zones_zonelist(node_zonelist(node, GFP_KERNEL),
3009 gfp_zone(GFP_KERNEL),
3016 #else /* CONFIG_NUMA */
3018 static void set_zonelist_order(void)
3020 current_zonelist_order = ZONELIST_ORDER_ZONE;
3023 static void build_zonelists(pg_data_t *pgdat)
3025 int node, local_node;
3027 struct zonelist *zonelist;
3029 local_node = pgdat->node_id;
3031 zonelist = &pgdat->node_zonelists[0];
3032 j = build_zonelists_node(pgdat, zonelist, 0, MAX_NR_ZONES - 1);
3035 * Now we build the zonelist so that it contains the zones
3036 * of all the other nodes.
3037 * We don't want to pressure a particular node, so when
3038 * building the zones for node N, we make sure that the
3039 * zones coming right after the local ones are those from
3040 * node N+1 (modulo N)
3042 for (node = local_node + 1; node < MAX_NUMNODES; node++) {
3043 if (!node_online(node))
3045 j = build_zonelists_node(NODE_DATA(node), zonelist, j,
3048 for (node = 0; node < local_node; node++) {
3049 if (!node_online(node))
3051 j = build_zonelists_node(NODE_DATA(node), zonelist, j,
3055 zonelist->_zonerefs[j].zone = NULL;
3056 zonelist->_zonerefs[j].zone_idx = 0;
3059 /* non-NUMA variant of zonelist performance cache - just NULL zlcache_ptr */
3060 static void build_zonelist_cache(pg_data_t *pgdat)
3062 pgdat->node_zonelists[0].zlcache_ptr = NULL;
3065 #endif /* CONFIG_NUMA */
3068 * Boot pageset table. One per cpu which is going to be used for all
3069 * zones and all nodes. The parameters will be set in such a way
3070 * that an item put on a list will immediately be handed over to
3071 * the buddy list. This is safe since pageset manipulation is done
3072 * with interrupts disabled.
3074 * The boot_pagesets must be kept even after bootup is complete for
3075 * unused processors and/or zones. They do play a role for bootstrapping
3076 * hotplugged processors.
3078 * zoneinfo_show() and maybe other functions do
3079 * not check if the processor is online before following the pageset pointer.
3080 * Other parts of the kernel may not check if the zone is available.
3082 static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch);
3083 static DEFINE_PER_CPU(struct per_cpu_pageset, boot_pageset);
3084 static void setup_zone_pageset(struct zone *zone);
3087 * Global mutex to protect against size modification of zonelists
3088 * as well as to serialize pageset setup for the new populated zone.
3090 DEFINE_MUTEX(zonelists_mutex);
3092 /* return values int ....just for stop_machine() */
3093 static __init_refok int __build_all_zonelists(void *data)
3099 memset(node_load, 0, sizeof(node_load));
3101 for_each_online_node(nid) {
3102 pg_data_t *pgdat = NODE_DATA(nid);
3104 build_zonelists(pgdat);
3105 build_zonelist_cache(pgdat);
3109 * Initialize the boot_pagesets that are going to be used
3110 * for bootstrapping processors. The real pagesets for
3111 * each zone will be allocated later when the per cpu
3112 * allocator is available.
3114 * boot_pagesets are used also for bootstrapping offline
3115 * cpus if the system is already booted because the pagesets
3116 * are needed to initialize allocators on a specific cpu too.
3117 * F.e. the percpu allocator needs the page allocator which
3118 * needs the percpu allocator in order to allocate its pagesets
3119 * (a chicken-egg dilemma).
3121 for_each_possible_cpu(cpu) {
3122 setup_pageset(&per_cpu(boot_pageset, cpu), 0);
3124 #ifdef CONFIG_HAVE_MEMORYLESS_NODES
3126 * We now know the "local memory node" for each node--
3127 * i.e., the node of the first zone in the generic zonelist.
3128 * Set up numa_mem percpu variable for on-line cpus. During
3129 * boot, only the boot cpu should be on-line; we'll init the
3130 * secondary cpus' numa_mem as they come on-line. During
3131 * node/memory hotplug, we'll fixup all on-line cpus.
3133 if (cpu_online(cpu))
3134 set_cpu_numa_mem(cpu, local_memory_node(cpu_to_node(cpu)));
3142 * Called with zonelists_mutex held always
3143 * unless system_state == SYSTEM_BOOTING.
3145 void build_all_zonelists(void *data)
3147 set_zonelist_order();
3149 if (system_state == SYSTEM_BOOTING) {
3150 __build_all_zonelists(NULL);
3151 mminit_verify_zonelist();
3152 cpuset_init_current_mems_allowed();
3154 /* we have to stop all cpus to guarantee there is no user
3156 #ifdef CONFIG_MEMORY_HOTPLUG
3158 setup_zone_pageset((struct zone *)data);
3160 stop_machine(__build_all_zonelists, NULL, NULL);
3161 /* cpuset refresh routine should be here */
3163 vm_total_pages = nr_free_pagecache_pages();
3165 * Disable grouping by mobility if the number of pages in the
3166 * system is too low to allow the mechanism to work. It would be
3167 * more accurate, but expensive to check per-zone. This check is
3168 * made on memory-hotadd so a system can start with mobility
3169 * disabled and enable it later
3171 if (vm_total_pages < (pageblock_nr_pages * MIGRATE_TYPES))
3172 page_group_by_mobility_disabled = 1;
3174 page_group_by_mobility_disabled = 0;
3176 printk("Built %i zonelists in %s order, mobility grouping %s. "
3177 "Total pages: %ld\n",
3179 zonelist_order_name[current_zonelist_order],
3180 page_group_by_mobility_disabled ? "off" : "on",
3183 printk("Policy zone: %s\n", zone_names[policy_zone]);
3188 * Helper functions to size the waitqueue hash table.
3189 * Essentially these want to choose hash table sizes sufficiently
3190 * large so that collisions trying to wait on pages are rare.
3191 * But in fact, the number of active page waitqueues on typical
3192 * systems is ridiculously low, less than 200. So this is even
3193 * conservative, even though it seems large.
3195 * The constant PAGES_PER_WAITQUEUE specifies the ratio of pages to
3196 * waitqueues, i.e. the size of the waitq table given the number of pages.
3198 #define PAGES_PER_WAITQUEUE 256
3200 #ifndef CONFIG_MEMORY_HOTPLUG
3201 static inline unsigned long wait_table_hash_nr_entries(unsigned long pages)
3203 unsigned long size = 1;
3205 pages /= PAGES_PER_WAITQUEUE;
3207 while (size < pages)
3211 * Once we have dozens or even hundreds of threads sleeping
3212 * on IO we've got bigger problems than wait queue collision.
3213 * Limit the size of the wait table to a reasonable size.
3215 size = min(size, 4096UL);
3217 return max(size, 4UL);
3221 * A zone's size might be changed by hot-add, so it is not possible to determine
3222 * a suitable size for its wait_table. So we use the maximum size now.
3224 * The max wait table size = 4096 x sizeof(wait_queue_head_t). ie:
3226 * i386 (preemption config) : 4096 x 16 = 64Kbyte.
3227 * ia64, x86-64 (no preemption): 4096 x 20 = 80Kbyte.
3228 * ia64, x86-64 (preemption) : 4096 x 24 = 96Kbyte.
3230 * The maximum entries are prepared when a zone's memory is (512K + 256) pages
3231 * or more by the traditional way. (See above). It equals:
3233 * i386, x86-64, powerpc(4K page size) : = ( 2G + 1M)byte.
3234 * ia64(16K page size) : = ( 8G + 4M)byte.
3235 * powerpc (64K page size) : = (32G +16M)byte.
3237 static inline unsigned long wait_table_hash_nr_entries(unsigned long pages)
3244 * This is an integer logarithm so that shifts can be used later
3245 * to extract the more random high bits from the multiplicative
3246 * hash function before the remainder is taken.
3248 static inline unsigned long wait_table_bits(unsigned long size)
3253 #define LONG_ALIGN(x) (((x)+(sizeof(long))-1)&~((sizeof(long))-1))
3256 * Mark a number of pageblocks as MIGRATE_RESERVE. The number
3257 * of blocks reserved is based on min_wmark_pages(zone). The memory within
3258 * the reserve will tend to store contiguous free pages. Setting min_free_kbytes
3259 * higher will lead to a bigger reserve which will get freed as contiguous
3260 * blocks as reclaim kicks in
3262 static void setup_zone_migrate_reserve(struct zone *zone)
3264 unsigned long start_pfn, pfn, end_pfn;
3266 unsigned long block_migratetype;
3269 /* Get the start pfn, end pfn and the number of blocks to reserve */
3270 start_pfn = zone->zone_start_pfn;
3271 end_pfn = start_pfn + zone->spanned_pages;
3272 reserve = roundup(min_wmark_pages(zone), pageblock_nr_pages) >>
3276 * Reserve blocks are generally in place to help high-order atomic
3277 * allocations that are short-lived. A min_free_kbytes value that
3278 * would result in more than 2 reserve blocks for atomic allocations
3279 * is assumed to be in place to help anti-fragmentation for the
3280 * future allocation of hugepages at runtime.
3282 reserve = min(2, reserve);
3284 for (pfn = start_pfn; pfn < end_pfn; pfn += pageblock_nr_pages) {
3285 if (!pfn_valid(pfn))
3287 page = pfn_to_page(pfn);
3289 /* Watch out for overlapping nodes */
3290 if (page_to_nid(page) != zone_to_nid(zone))
3293 /* Blocks with reserved pages will never free, skip them. */
3294 if (PageReserved(page))
3297 block_migratetype = get_pageblock_migratetype(page);
3299 /* If this block is reserved, account for it */
3300 if (reserve > 0 && block_migratetype == MIGRATE_RESERVE) {
3305 /* Suitable for reserving if this block is movable */
3306 if (reserve > 0 && block_migratetype == MIGRATE_MOVABLE) {
3307 set_pageblock_migratetype(page, MIGRATE_RESERVE);
3308 move_freepages_block(zone, page, MIGRATE_RESERVE);
3314 * If the reserve is met and this is a previous reserved block,
3317 if (block_migratetype == MIGRATE_RESERVE) {
3318 set_pageblock_migratetype(page, MIGRATE_MOVABLE);
3319 move_freepages_block(zone, page, MIGRATE_MOVABLE);
3325 * Initially all pages are reserved - free ones are freed
3326 * up by free_all_bootmem() once the early boot process is
3327 * done. Non-atomic initialization, single-pass.
3329 void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone,
3330 unsigned long start_pfn, enum memmap_context context)
3333 unsigned long end_pfn = start_pfn + size;
3337 if (highest_memmap_pfn < end_pfn - 1)
3338 highest_memmap_pfn = end_pfn - 1;
3340 z = &NODE_DATA(nid)->node_zones[zone];
3341 for (pfn = start_pfn; pfn < end_pfn; pfn++) {
3343 * There can be holes in boot-time mem_map[]s
3344 * handed to this function. They do not
3345 * exist on hotplugged memory.
3347 if (context == MEMMAP_EARLY) {
3348 if (!early_pfn_valid(pfn))
3350 if (!early_pfn_in_nid(pfn, nid))
3353 page = pfn_to_page(pfn);
3354 set_page_links(page, zone, nid, pfn);
3355 mminit_verify_page_links(page, zone, nid, pfn);
3356 init_page_count(page);
3357 reset_page_mapcount(page);
3358 SetPageReserved(page);
3360 * Mark the block movable so that blocks are reserved for
3361 * movable at startup. This will force kernel allocations
3362 * to reserve their blocks rather than leaking throughout
3363 * the address space during boot when many long-lived
3364 * kernel allocations are made. Later some blocks near
3365 * the start are marked MIGRATE_RESERVE by
3366 * setup_zone_migrate_reserve()
3368 * bitmap is created for zone's valid pfn range. but memmap
3369 * can be created for invalid pages (for alignment)
3370 * check here not to call set_pageblock_migratetype() against
3373 if ((z->zone_start_pfn <= pfn)
3374 && (pfn < z->zone_start_pfn + z->spanned_pages)
3375 && !(pfn & (pageblock_nr_pages - 1)))
3376 set_pageblock_migratetype(page, MIGRATE_MOVABLE);
3378 INIT_LIST_HEAD(&page->lru);
3379 #ifdef WANT_PAGE_VIRTUAL
3380 /* The shift won't overflow because ZONE_NORMAL is below 4G. */
3381 if (!is_highmem_idx(zone))
3382 set_page_address(page, __va(pfn << PAGE_SHIFT));
3387 static void __meminit zone_init_free_lists(struct zone *zone)
3390 for_each_migratetype_order(order, t) {
3391 INIT_LIST_HEAD(&zone->free_area[order].free_list[t]);
3392 zone->free_area[order].nr_free = 0;
3396 #ifndef __HAVE_ARCH_MEMMAP_INIT
3397 #define memmap_init(size, nid, zone, start_pfn) \
3398 memmap_init_zone((size), (nid), (zone), (start_pfn), MEMMAP_EARLY)
3401 static int zone_batchsize(struct zone *zone)
3407 * The per-cpu-pages pools are set to around 1000th of the
3408 * size of the zone. But no more than 1/2 of a meg.
3410 * OK, so we don't know how big the cache is. So guess.
3412 batch = zone->present_pages / 1024;
3413 if (batch * PAGE_SIZE > 512 * 1024)
3414 batch = (512 * 1024) / PAGE_SIZE;
3415 batch /= 4; /* We effectively *= 4 below */
3420 * Clamp the batch to a 2^n - 1 value. Having a power
3421 * of 2 value was found to be more likely to have
3422 * suboptimal cache aliasing properties in some cases.
3424 * For example if 2 tasks are alternately allocating
3425 * batches of pages, one task can end up with a lot
3426 * of pages of one half of the possible page colors
3427 * and the other with pages of the other colors.
3429 batch = rounddown_pow_of_two(batch + batch/2) - 1;
3434 /* The deferral and batching of frees should be suppressed under NOMMU
3437 * The problem is that NOMMU needs to be able to allocate large chunks
3438 * of contiguous memory as there's no hardware page translation to
3439 * assemble apparent contiguous memory from discontiguous pages.
3441 * Queueing large contiguous runs of pages for batching, however,
3442 * causes the pages to actually be freed in smaller chunks. As there
3443 * can be a significant delay between the individual batches being
3444 * recycled, this leads to the once large chunks of space being
3445 * fragmented and becoming unavailable for high-order allocations.
3451 static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch)
3453 struct per_cpu_pages *pcp;
3456 memset(p, 0, sizeof(*p));
3460 pcp->high = 6 * batch;
3461 pcp->batch = max(1UL, 1 * batch);
3462 for (migratetype = 0; migratetype < MIGRATE_PCPTYPES; migratetype++)
3463 INIT_LIST_HEAD(&pcp->lists[migratetype]);
3467 * setup_pagelist_highmark() sets the high water mark for hot per_cpu_pagelist
3468 * to the value high for the pageset p.
3471 static void setup_pagelist_highmark(struct per_cpu_pageset *p,
3474 struct per_cpu_pages *pcp;
3478 pcp->batch = max(1UL, high/4);
3479 if ((high/4) > (PAGE_SHIFT * 8))
3480 pcp->batch = PAGE_SHIFT * 8;
3483 static __meminit void setup_zone_pageset(struct zone *zone)
3487 zone->pageset = alloc_percpu(struct per_cpu_pageset);
3489 for_each_possible_cpu(cpu) {
3490 struct per_cpu_pageset *pcp = per_cpu_ptr(zone->pageset, cpu);
3492 setup_pageset(pcp, zone_batchsize(zone));
3494 if (percpu_pagelist_fraction)
3495 setup_pagelist_highmark(pcp,
3496 (zone->present_pages /
3497 percpu_pagelist_fraction));
3502 * Allocate per cpu pagesets and initialize them.
3503 * Before this call only boot pagesets were available.
3505 void __init setup_per_cpu_pageset(void)
3509 for_each_populated_zone(zone)
3510 setup_zone_pageset(zone);
3513 static noinline __init_refok
3514 int zone_wait_table_init(struct zone *zone, unsigned long zone_size_pages)
3517 struct pglist_data *pgdat = zone->zone_pgdat;
3521 * The per-page waitqueue mechanism uses hashed waitqueues
3524 zone->wait_table_hash_nr_entries =
3525 wait_table_hash_nr_entries(zone_size_pages);
3526 zone->wait_table_bits =
3527 wait_table_bits(zone->wait_table_hash_nr_entries);
3528 alloc_size = zone->wait_table_hash_nr_entries
3529 * sizeof(wait_queue_head_t);
3531 if (!slab_is_available()) {
3532 zone->wait_table = (wait_queue_head_t *)
3533 alloc_bootmem_node(pgdat, alloc_size);
3536 * This case means that a zone whose size was 0 gets new memory
3537 * via memory hot-add.
3538 * But it may be the case that a new node was hot-added. In
3539 * this case vmalloc() will not be able to use this new node's
3540 * memory - this wait_table must be initialized to use this new
3541 * node itself as well.
3542 * To use this new node's memory, further consideration will be
3545 zone->wait_table = vmalloc(alloc_size);
3547 if (!zone->wait_table)
3550 for(i = 0; i < zone->wait_table_hash_nr_entries; ++i)
3551 init_waitqueue_head(zone->wait_table + i);
3556 static int __zone_pcp_update(void *data)
3558 struct zone *zone = data;
3560 unsigned long batch = zone_batchsize(zone), flags;
3562 for_each_possible_cpu(cpu) {
3563 struct per_cpu_pageset *pset;
3564 struct per_cpu_pages *pcp;
3566 pset = per_cpu_ptr(zone->pageset, cpu);
3569 local_irq_save(flags);
3570 free_pcppages_bulk(zone, pcp->count, pcp);
3571 setup_pageset(pset, batch);
3572 local_irq_restore(flags);
3577 void zone_pcp_update(struct zone *zone)
3579 stop_machine(__zone_pcp_update, zone, NULL);
3582 static __meminit void zone_pcp_init(struct zone *zone)
3585 * per cpu subsystem is not up at this point. The following code
3586 * relies on the ability of the linker to provide the
3587 * offset of a (static) per cpu variable into the per cpu area.
3589 zone->pageset = &boot_pageset;
3591 if (zone->present_pages)
3592 printk(KERN_DEBUG " %s zone: %lu pages, LIFO batch:%u\n",
3593 zone->name, zone->present_pages,
3594 zone_batchsize(zone));
3597 __meminit int init_currently_empty_zone(struct zone *zone,
3598 unsigned long zone_start_pfn,
3600 enum memmap_context context)
3602 struct pglist_data *pgdat = zone->zone_pgdat;
3604 ret = zone_wait_table_init(zone, size);
3607 pgdat->nr_zones = zone_idx(zone) + 1;
3609 zone->zone_start_pfn = zone_start_pfn;
3611 mminit_dprintk(MMINIT_TRACE, "memmap_init",
3612 "Initialising map node %d zone %lu pfns %lu -> %lu\n",
3614 (unsigned long)zone_idx(zone),
3615 zone_start_pfn, (zone_start_pfn + size));
3617 zone_init_free_lists(zone);
3622 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
3624 * Basic iterator support. Return the first range of PFNs for a node
3625 * Note: nid == MAX_NUMNODES returns first region regardless of node
3627 static int __meminit first_active_region_index_in_nid(int nid)
3631 for (i = 0; i < nr_nodemap_entries; i++)
3632 if (nid == MAX_NUMNODES || early_node_map[i].nid == nid)
3639 * Basic iterator support. Return the next active range of PFNs for a node
3640 * Note: nid == MAX_NUMNODES returns next region regardless of node
3642 static int __meminit next_active_region_index_in_nid(int index, int nid)
3644 for (index = index + 1; index < nr_nodemap_entries; index++)
3645 if (nid == MAX_NUMNODES || early_node_map[index].nid == nid)
3651 #ifndef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
3653 * Required by SPARSEMEM. Given a PFN, return what node the PFN is on.
3654 * Architectures may implement their own version but if add_active_range()
3655 * was used and there are no special requirements, this is a convenient
3658 int __meminit __early_pfn_to_nid(unsigned long pfn)
3662 for (i = 0; i < nr_nodemap_entries; i++) {
3663 unsigned long start_pfn = early_node_map[i].start_pfn;
3664 unsigned long end_pfn = early_node_map[i].end_pfn;
3666 if (start_pfn <= pfn && pfn < end_pfn)
3667 return early_node_map[i].nid;
3669 /* This is a memory hole */
3672 #endif /* CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID */
3674 int __meminit early_pfn_to_nid(unsigned long pfn)
3678 nid = __early_pfn_to_nid(pfn);
3681 /* just returns 0 */
3685 #ifdef CONFIG_NODES_SPAN_OTHER_NODES
3686 bool __meminit early_pfn_in_nid(unsigned long pfn, int node)
3690 nid = __early_pfn_to_nid(pfn);
3691 if (nid >= 0 && nid != node)
3697 /* Basic iterator support to walk early_node_map[] */
3698 #define for_each_active_range_index_in_nid(i, nid) \
3699 for (i = first_active_region_index_in_nid(nid); i != -1; \
3700 i = next_active_region_index_in_nid(i, nid))
3703 * free_bootmem_with_active_regions - Call free_bootmem_node for each active range
3704 * @nid: The node to free memory on. If MAX_NUMNODES, all nodes are freed.
3705 * @max_low_pfn: The highest PFN that will be passed to free_bootmem_node
3707 * If an architecture guarantees that all ranges registered with
3708 * add_active_ranges() contain no holes and may be freed, this
3709 * this function may be used instead of calling free_bootmem() manually.
3711 void __init free_bootmem_with_active_regions(int nid,
3712 unsigned long max_low_pfn)
3716 for_each_active_range_index_in_nid(i, nid) {
3717 unsigned long size_pages = 0;
3718 unsigned long end_pfn = early_node_map[i].end_pfn;
3720 if (early_node_map[i].start_pfn >= max_low_pfn)
3723 if (end_pfn > max_low_pfn)
3724 end_pfn = max_low_pfn;
3726 size_pages = end_pfn - early_node_map[i].start_pfn;
3727 free_bootmem_node(NODE_DATA(early_node_map[i].nid),
3728 PFN_PHYS(early_node_map[i].start_pfn),
3729 size_pages << PAGE_SHIFT);
3733 #ifdef CONFIG_HAVE_MEMBLOCK
3735 * Basic iterator support. Return the last range of PFNs for a node
3736 * Note: nid == MAX_NUMNODES returns last region regardless of node
3738 static int __meminit last_active_region_index_in_nid(int nid)
3742 for (i = nr_nodemap_entries - 1; i >= 0; i--)
3743 if (nid == MAX_NUMNODES || early_node_map[i].nid == nid)
3750 * Basic iterator support. Return the previous active range of PFNs for a node
3751 * Note: nid == MAX_NUMNODES returns next region regardless of node
3753 static int __meminit previous_active_region_index_in_nid(int index, int nid)
3755 for (index = index - 1; index >= 0; index--)
3756 if (nid == MAX_NUMNODES || early_node_map[index].nid == nid)
3762 #define for_each_active_range_index_in_nid_reverse(i, nid) \
3763 for (i = last_active_region_index_in_nid(nid); i != -1; \
3764 i = previous_active_region_index_in_nid(i, nid))
3766 u64 __init find_memory_core_early(int nid, u64 size, u64 align,
3767 u64 goal, u64 limit)
3771 /* Need to go over early_node_map to find out good range for node */
3772 for_each_active_range_index_in_nid_reverse(i, nid) {
3774 u64 ei_start, ei_last;
3775 u64 final_start, final_end;
3777 ei_last = early_node_map[i].end_pfn;
3778 ei_last <<= PAGE_SHIFT;
3779 ei_start = early_node_map[i].start_pfn;
3780 ei_start <<= PAGE_SHIFT;
3782 final_start = max(ei_start, goal);
3783 final_end = min(ei_last, limit);
3785 if (final_start >= final_end)
3788 addr = memblock_find_in_range(final_start, final_end, size, align);
3790 if (addr == MEMBLOCK_ERROR)
3796 return MEMBLOCK_ERROR;
3800 int __init add_from_early_node_map(struct range *range, int az,
3801 int nr_range, int nid)
3806 /* need to go over early_node_map to find out good range for node */
3807 for_each_active_range_index_in_nid(i, nid) {
3808 start = early_node_map[i].start_pfn;
3809 end = early_node_map[i].end_pfn;
3810 nr_range = add_range(range, az, nr_range, start, end);
3815 void __init work_with_active_regions(int nid, work_fn_t work_fn, void *data)
3820 for_each_active_range_index_in_nid(i, nid) {
3821 ret = work_fn(early_node_map[i].start_pfn,
3822 early_node_map[i].end_pfn, data);
3828 * sparse_memory_present_with_active_regions - Call memory_present for each active range
3829 * @nid: The node to call memory_present for. If MAX_NUMNODES, all nodes will be used.
3831 * If an architecture guarantees that all ranges registered with
3832 * add_active_ranges() contain no holes and may be freed, this
3833 * function may be used instead of calling memory_present() manually.
3835 void __init sparse_memory_present_with_active_regions(int nid)
3839 for_each_active_range_index_in_nid(i, nid)
3840 memory_present(early_node_map[i].nid,
3841 early_node_map[i].start_pfn,
3842 early_node_map[i].end_pfn);
3846 * get_pfn_range_for_nid - Return the start and end page frames for a node
3847 * @nid: The nid to return the range for. If MAX_NUMNODES, the min and max PFN are returned.
3848 * @start_pfn: Passed by reference. On return, it will have the node start_pfn.
3849 * @end_pfn: Passed by reference. On return, it will have the node end_pfn.
3851 * It returns the start and end page frame of a node based on information
3852 * provided by an arch calling add_active_range(). If called for a node
3853 * with no available memory, a warning is printed and the start and end
3856 void __meminit get_pfn_range_for_nid(unsigned int nid,
3857 unsigned long *start_pfn, unsigned long *end_pfn)
3863 for_each_active_range_index_in_nid(i, nid) {
3864 *start_pfn = min(*start_pfn, early_node_map[i].start_pfn);
3865 *end_pfn = max(*end_pfn, early_node_map[i].end_pfn);
3868 if (*start_pfn == -1UL)
3873 * This finds a zone that can be used for ZONE_MOVABLE pages. The
3874 * assumption is made that zones within a node are ordered in monotonic
3875 * increasing memory addresses so that the "highest" populated zone is used
3877 static void __init find_usable_zone_for_movable(void)
3880 for (zone_index = MAX_NR_ZONES - 1; zone_index >= 0; zone_index--) {
3881 if (zone_index == ZONE_MOVABLE)
3884 if (arch_zone_highest_possible_pfn[zone_index] >
3885 arch_zone_lowest_possible_pfn[zone_index])
3889 VM_BUG_ON(zone_index == -1);
3890 movable_zone = zone_index;
3894 * The zone ranges provided by the architecture do not include ZONE_MOVABLE
3895 * because it is sized independant of architecture. Unlike the other zones,
3896 * the starting point for ZONE_MOVABLE is not fixed. It may be different
3897 * in each node depending on the size of each node and how evenly kernelcore
3898 * is distributed. This helper function adjusts the zone ranges
3899 * provided by the architecture for a given node by using the end of the
3900 * highest usable zone for ZONE_MOVABLE. This preserves the assumption that
3901 * zones within a node are in order of monotonic increases memory addresses
3903 static void __meminit adjust_zone_range_for_zone_movable(int nid,
3904 unsigned long zone_type,
3905 unsigned long node_start_pfn,
3906 unsigned long node_end_pfn,
3907 unsigned long *zone_start_pfn,
3908 unsigned long *zone_end_pfn)
3910 /* Only adjust if ZONE_MOVABLE is on this node */
3911 if (zone_movable_pfn[nid]) {
3912 /* Size ZONE_MOVABLE */
3913 if (zone_type == ZONE_MOVABLE) {
3914 *zone_start_pfn = zone_movable_pfn[nid];
3915 *zone_end_pfn = min(node_end_pfn,
3916 arch_zone_highest_possible_pfn[movable_zone]);
3918 /* Adjust for ZONE_MOVABLE starting within this range */
3919 } else if (*zone_start_pfn < zone_movable_pfn[nid] &&
3920 *zone_end_pfn > zone_movable_pfn[nid]) {
3921 *zone_end_pfn = zone_movable_pfn[nid];
3923 /* Check if this whole range is within ZONE_MOVABLE */
3924 } else if (*zone_start_pfn >= zone_movable_pfn[nid])
3925 *zone_start_pfn = *zone_end_pfn;
3930 * Return the number of pages a zone spans in a node, including holes
3931 * present_pages = zone_spanned_pages_in_node() - zone_absent_pages_in_node()
3933 static unsigned long __meminit zone_spanned_pages_in_node(int nid,
3934 unsigned long zone_type,
3935 unsigned long *ignored)
3937 unsigned long node_start_pfn, node_end_pfn;
3938 unsigned long zone_start_pfn, zone_end_pfn;
3940 /* Get the start and end of the node and zone */
3941 get_pfn_range_for_nid(nid, &node_start_pfn, &node_end_pfn);
3942 zone_start_pfn = arch_zone_lowest_possible_pfn[zone_type];
3943 zone_end_pfn = arch_zone_highest_possible_pfn[zone_type];
3944 adjust_zone_range_for_zone_movable(nid, zone_type,
3945 node_start_pfn, node_end_pfn,
3946 &zone_start_pfn, &zone_end_pfn);
3948 /* Check that this node has pages within the zone's required range */
3949 if (zone_end_pfn < node_start_pfn || zone_start_pfn > node_end_pfn)
3952 /* Move the zone boundaries inside the node if necessary */
3953 zone_end_pfn = min(zone_end_pfn, node_end_pfn);
3954 zone_start_pfn = max(zone_start_pfn, node_start_pfn);
3956 /* Return the spanned pages */
3957 return zone_end_pfn - zone_start_pfn;
3961 * Return the number of holes in a range on a node. If nid is MAX_NUMNODES,
3962 * then all holes in the requested range will be accounted for.
3964 unsigned long __meminit __absent_pages_in_range(int nid,
3965 unsigned long range_start_pfn,
3966 unsigned long range_end_pfn)
3969 unsigned long prev_end_pfn = 0, hole_pages = 0;
3970 unsigned long start_pfn;
3972 /* Find the end_pfn of the first active range of pfns in the node */
3973 i = first_active_region_index_in_nid(nid);
3977 prev_end_pfn = min(early_node_map[i].start_pfn, range_end_pfn);
3979 /* Account for ranges before physical memory on this node */
3980 if (early_node_map[i].start_pfn > range_start_pfn)
3981 hole_pages = prev_end_pfn - range_start_pfn;
3983 /* Find all holes for the zone within the node */
3984 for (; i != -1; i = next_active_region_index_in_nid(i, nid)) {
3986 /* No need to continue if prev_end_pfn is outside the zone */
3987 if (prev_end_pfn >= range_end_pfn)
3990 /* Make sure the end of the zone is not within the hole */
3991 start_pfn = min(early_node_map[i].start_pfn, range_end_pfn);
3992 prev_end_pfn = max(prev_end_pfn, range_start_pfn);
3994 /* Update the hole size cound and move on */
3995 if (start_pfn > range_start_pfn) {
3996 BUG_ON(prev_end_pfn > start_pfn);
3997 hole_pages += start_pfn - prev_end_pfn;
3999 prev_end_pfn = early_node_map[i].end_pfn;
4002 /* Account for ranges past physical memory on this node */
4003 if (range_end_pfn > prev_end_pfn)
4004 hole_pages += range_end_pfn -
4005 max(range_start_pfn, prev_end_pfn);
4011 * absent_pages_in_range - Return number of page frames in holes within a range
4012 * @start_pfn: The start PFN to start searching for holes
4013 * @end_pfn: The end PFN to stop searching for holes
4015 * It returns the number of pages frames in memory holes within a range.
4017 unsigned long __init absent_pages_in_range(unsigned long start_pfn,
4018 unsigned long end_pfn)
4020 return __absent_pages_in_range(MAX_NUMNODES, start_pfn, end_pfn);
4023 /* Return the number of page frames in holes in a zone on a node */
4024 static unsigned long __meminit zone_absent_pages_in_node(int nid,
4025 unsigned long zone_type,
4026 unsigned long *ignored)
4028 unsigned long node_start_pfn, node_end_pfn;
4029 unsigned long zone_start_pfn, zone_end_pfn;
4031 get_pfn_range_for_nid(nid, &node_start_pfn, &node_end_pfn);
4032 zone_start_pfn = max(arch_zone_lowest_possible_pfn[zone_type],
4034 zone_end_pfn = min(arch_zone_highest_possible_pfn[zone_type],
4037 adjust_zone_range_for_zone_movable(nid, zone_type,
4038 node_start_pfn, node_end_pfn,
4039 &zone_start_pfn, &zone_end_pfn);
4040 return __absent_pages_in_range(nid, zone_start_pfn, zone_end_pfn);
4044 static inline unsigned long __meminit zone_spanned_pages_in_node(int nid,
4045 unsigned long zone_type,
4046 unsigned long *zones_size)
4048 return zones_size[zone_type];
4051 static inline unsigned long __meminit zone_absent_pages_in_node(int nid,
4052 unsigned long zone_type,
4053 unsigned long *zholes_size)
4058 return zholes_size[zone_type];
4063 static void __meminit calculate_node_totalpages(struct pglist_data *pgdat,
4064 unsigned long *zones_size, unsigned long *zholes_size)
4066 unsigned long realtotalpages, totalpages = 0;
4069 for (i = 0; i < MAX_NR_ZONES; i++)
4070 totalpages += zone_spanned_pages_in_node(pgdat->node_id, i,
4072 pgdat->node_spanned_pages = totalpages;
4074 realtotalpages = totalpages;
4075 for (i = 0; i < MAX_NR_ZONES; i++)
4077 zone_absent_pages_in_node(pgdat->node_id, i,
4079 pgdat->node_present_pages = realtotalpages;
4080 printk(KERN_DEBUG "On node %d totalpages: %lu\n", pgdat->node_id,
4084 #ifndef CONFIG_SPARSEMEM
4086 * Calculate the size of the zone->blockflags rounded to an unsigned long
4087 * Start by making sure zonesize is a multiple of pageblock_order by rounding
4088 * up. Then use 1 NR_PAGEBLOCK_BITS worth of bits per pageblock, finally
4089 * round what is now in bits to nearest long in bits, then return it in
4092 static unsigned long __init usemap_size(unsigned long zonesize)
4094 unsigned long usemapsize;
4096 usemapsize = roundup(zonesize, pageblock_nr_pages);
4097 usemapsize = usemapsize >> pageblock_order;
4098 usemapsize *= NR_PAGEBLOCK_BITS;
4099 usemapsize = roundup(usemapsize, 8 * sizeof(unsigned long));
4101 return usemapsize / 8;
4104 static void __init setup_usemap(struct pglist_data *pgdat,
4105 struct zone *zone, unsigned long zonesize)
4107 unsigned long usemapsize = usemap_size(zonesize);
4108 zone->pageblock_flags = NULL;
4110 zone->pageblock_flags = alloc_bootmem_node(pgdat, usemapsize);
4113 static inline void setup_usemap(struct pglist_data *pgdat,
4114 struct zone *zone, unsigned long zonesize) {}
4115 #endif /* CONFIG_SPARSEMEM */
4117 #ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
4119 /* Return a sensible default order for the pageblock size. */
4120 static inline int pageblock_default_order(void)
4122 if (HPAGE_SHIFT > PAGE_SHIFT)
4123 return HUGETLB_PAGE_ORDER;
4128 /* Initialise the number of pages represented by NR_PAGEBLOCK_BITS */
4129 static inline void __init set_pageblock_order(unsigned int order)
4131 /* Check that pageblock_nr_pages has not already been setup */
4132 if (pageblock_order)
4136 * Assume the largest contiguous order of interest is a huge page.
4137 * This value may be variable depending on boot parameters on IA64
4139 pageblock_order = order;
4141 #else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
4144 * When CONFIG_HUGETLB_PAGE_SIZE_VARIABLE is not set, set_pageblock_order()
4145 * and pageblock_default_order() are unused as pageblock_order is set
4146 * at compile-time. See include/linux/pageblock-flags.h for the values of
4147 * pageblock_order based on the kernel config
4149 static inline int pageblock_default_order(unsigned int order)
4153 #define set_pageblock_order(x) do {} while (0)
4155 #endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
4158 * Set up the zone data structures:
4159 * - mark all pages reserved
4160 * - mark all memory queues empty
4161 * - clear the memory bitmaps
4163 static void __paginginit free_area_init_core(struct pglist_data *pgdat,
4164 unsigned long *zones_size, unsigned long *zholes_size)
4167 int nid = pgdat->node_id;
4168 unsigned long zone_start_pfn = pgdat->node_start_pfn;
4171 pgdat_resize_init(pgdat);
4172 pgdat->nr_zones = 0;
4173 init_waitqueue_head(&pgdat->kswapd_wait);
4174 pgdat->kswapd_max_order = 0;
4175 pgdat_page_cgroup_init(pgdat);
4177 for (j = 0; j < MAX_NR_ZONES; j++) {
4178 struct zone *zone = pgdat->node_zones + j;
4179 unsigned long size, realsize, memmap_pages;
4182 size = zone_spanned_pages_in_node(nid, j, zones_size);
4183 realsize = size - zone_absent_pages_in_node(nid, j,
4187 * Adjust realsize so that it accounts for how much memory
4188 * is used by this zone for memmap. This affects the watermark
4189 * and per-cpu initialisations
4192 PAGE_ALIGN(size * sizeof(struct page)) >> PAGE_SHIFT;
4193 if (realsize >= memmap_pages) {
4194 realsize -= memmap_pages;
4197 " %s zone: %lu pages used for memmap\n",
4198 zone_names[j], memmap_pages);
4201 " %s zone: %lu pages exceeds realsize %lu\n",
4202 zone_names[j], memmap_pages, realsize);
4204 /* Account for reserved pages */
4205 if (j == 0 && realsize > dma_reserve) {
4206 realsize -= dma_reserve;
4207 printk(KERN_DEBUG " %s zone: %lu pages reserved\n",
4208 zone_names[0], dma_reserve);
4211 if (!is_highmem_idx(j))
4212 nr_kernel_pages += realsize;
4213 nr_all_pages += realsize;
4215 zone->spanned_pages = size;
4216 zone->present_pages = realsize;
4219 zone->min_unmapped_pages = (realsize*sysctl_min_unmapped_ratio)
4221 zone->min_slab_pages = (realsize * sysctl_min_slab_ratio) / 100;
4223 zone->name = zone_names[j];
4224 spin_lock_init(&zone->lock);
4225 spin_lock_init(&zone->lru_lock);
4226 zone_seqlock_init(zone);
4227 zone->zone_pgdat = pgdat;
4229 zone_pcp_init(zone);
4231 INIT_LIST_HEAD(&zone->lru[l].list);
4232 zone->reclaim_stat.nr_saved_scan[l] = 0;
4234 zone->reclaim_stat.recent_rotated[0] = 0;
4235 zone->reclaim_stat.recent_rotated[1] = 0;
4236 zone->reclaim_stat.recent_scanned[0] = 0;
4237 zone->reclaim_stat.recent_scanned[1] = 0;
4238 zap_zone_vm_stats(zone);
4243 set_pageblock_order(pageblock_default_order());
4244 setup_usemap(pgdat, zone, size);
4245 ret = init_currently_empty_zone(zone, zone_start_pfn,
4246 size, MEMMAP_EARLY);
4248 memmap_init(size, nid, j, zone_start_pfn);
4249 zone_start_pfn += size;
4253 static void __init_refok alloc_node_mem_map(struct pglist_data *pgdat)
4255 /* Skip empty nodes */
4256 if (!pgdat->node_spanned_pages)
4259 #ifdef CONFIG_FLAT_NODE_MEM_MAP
4260 /* ia64 gets its own node_mem_map, before this, without bootmem */
4261 if (!pgdat->node_mem_map) {
4262 unsigned long size, start, end;
4266 * The zone's endpoints aren't required to be MAX_ORDER
4267 * aligned but the node_mem_map endpoints must be in order
4268 * for the buddy allocator to function correctly.
4270 start = pgdat->node_start_pfn & ~(MAX_ORDER_NR_PAGES - 1);
4271 end = pgdat->node_start_pfn + pgdat->node_spanned_pages;
4272 end = ALIGN(end, MAX_ORDER_NR_PAGES);
4273 size = (end - start) * sizeof(struct page);
4274 map = alloc_remap(pgdat->node_id, size);
4276 map = alloc_bootmem_node(pgdat, size);
4277 pgdat->node_mem_map = map + (pgdat->node_start_pfn - start);
4279 #ifndef CONFIG_NEED_MULTIPLE_NODES
4281 * With no DISCONTIG, the global mem_map is just set as node 0's
4283 if (pgdat == NODE_DATA(0)) {
4284 mem_map = NODE_DATA(0)->node_mem_map;
4285 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
4286 if (page_to_pfn(mem_map) != pgdat->node_start_pfn)
4287 mem_map -= (pgdat->node_start_pfn - ARCH_PFN_OFFSET);
4288 #endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
4291 #endif /* CONFIG_FLAT_NODE_MEM_MAP */
4294 void __paginginit free_area_init_node(int nid, unsigned long *zones_size,
4295 unsigned long node_start_pfn, unsigned long *zholes_size)
4297 pg_data_t *pgdat = NODE_DATA(nid);
4299 pgdat->node_id = nid;
4300 pgdat->node_start_pfn = node_start_pfn;
4301 calculate_node_totalpages(pgdat, zones_size, zholes_size);
4303 alloc_node_mem_map(pgdat);
4304 #ifdef CONFIG_FLAT_NODE_MEM_MAP
4305 printk(KERN_DEBUG "free_area_init_node: node %d, pgdat %08lx, node_mem_map %08lx\n",
4306 nid, (unsigned long)pgdat,
4307 (unsigned long)pgdat->node_mem_map);
4310 free_area_init_core(pgdat, zones_size, zholes_size);
4313 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
4315 #if MAX_NUMNODES > 1
4317 * Figure out the number of possible node ids.
4319 static void __init setup_nr_node_ids(void)
4322 unsigned int highest = 0;
4324 for_each_node_mask(node, node_possible_map)
4326 nr_node_ids = highest + 1;
4329 static inline void setup_nr_node_ids(void)
4335 * add_active_range - Register a range of PFNs backed by physical memory
4336 * @nid: The node ID the range resides on
4337 * @start_pfn: The start PFN of the available physical memory
4338 * @end_pfn: The end PFN of the available physical memory
4340 * These ranges are stored in an early_node_map[] and later used by
4341 * free_area_init_nodes() to calculate zone sizes and holes. If the
4342 * range spans a memory hole, it is up to the architecture to ensure
4343 * the memory is not freed by the bootmem allocator. If possible
4344 * the range being registered will be merged with existing ranges.
4346 void __init add_active_range(unsigned int nid, unsigned long start_pfn,
4347 unsigned long end_pfn)
4351 mminit_dprintk(MMINIT_TRACE, "memory_register",
4352 "Entering add_active_range(%d, %#lx, %#lx) "
4353 "%d entries of %d used\n",
4354 nid, start_pfn, end_pfn,
4355 nr_nodemap_entries, MAX_ACTIVE_REGIONS);
4357 mminit_validate_memmodel_limits(&start_pfn, &end_pfn);
4359 /* Merge with existing active regions if possible */
4360 for (i = 0; i < nr_nodemap_entries; i++) {
4361 if (early_node_map[i].nid != nid)
4364 /* Skip if an existing region covers this new one */
4365 if (start_pfn >= early_node_map[i].start_pfn &&
4366 end_pfn <= early_node_map[i].end_pfn)
4369 /* Merge forward if suitable */
4370 if (start_pfn <= early_node_map[i].end_pfn &&
4371 end_pfn > early_node_map[i].end_pfn) {
4372 early_node_map[i].end_pfn = end_pfn;
4376 /* Merge backward if suitable */
4377 if (start_pfn < early_node_map[i].start_pfn &&
4378 end_pfn >= early_node_map[i].start_pfn) {
4379 early_node_map[i].start_pfn = start_pfn;
4384 /* Check that early_node_map is large enough */
4385 if (i >= MAX_ACTIVE_REGIONS) {
4386 printk(KERN_CRIT "More than %d memory regions, truncating\n",
4387 MAX_ACTIVE_REGIONS);
4391 early_node_map[i].nid = nid;
4392 early_node_map[i].start_pfn = start_pfn;
4393 early_node_map[i].end_pfn = end_pfn;
4394 nr_nodemap_entries = i + 1;
4398 * remove_active_range - Shrink an existing registered range of PFNs
4399 * @nid: The node id the range is on that should be shrunk
4400 * @start_pfn: The new PFN of the range
4401 * @end_pfn: The new PFN of the range
4403 * i386 with NUMA use alloc_remap() to store a node_mem_map on a local node.
4404 * The map is kept near the end physical page range that has already been
4405 * registered. This function allows an arch to shrink an existing registered
4408 void __init remove_active_range(unsigned int nid, unsigned long start_pfn,
4409 unsigned long end_pfn)
4414 printk(KERN_DEBUG "remove_active_range (%d, %lu, %lu)\n",
4415 nid, start_pfn, end_pfn);
4417 /* Find the old active region end and shrink */
4418 for_each_active_range_index_in_nid(i, nid) {
4419 if (early_node_map[i].start_pfn >= start_pfn &&
4420 early_node_map[i].end_pfn <= end_pfn) {
4422 early_node_map[i].start_pfn = 0;
4423 early_node_map[i].end_pfn = 0;
4427 if (early_node_map[i].start_pfn < start_pfn &&
4428 early_node_map[i].end_pfn > start_pfn) {
4429 unsigned long temp_end_pfn = early_node_map[i].end_pfn;
4430 early_node_map[i].end_pfn = start_pfn;
4431 if (temp_end_pfn > end_pfn)
4432 add_active_range(nid, end_pfn, temp_end_pfn);
4435 if (early_node_map[i].start_pfn >= start_pfn &&
4436 early_node_map[i].end_pfn > end_pfn &&
4437 early_node_map[i].start_pfn < end_pfn) {
4438 early_node_map[i].start_pfn = end_pfn;
4446 /* remove the blank ones */
4447 for (i = nr_nodemap_entries - 1; i > 0; i--) {
4448 if (early_node_map[i].nid != nid)
4450 if (early_node_map[i].end_pfn)
4452 /* we found it, get rid of it */
4453 for (j = i; j < nr_nodemap_entries - 1; j++)
4454 memcpy(&early_node_map[j], &early_node_map[j+1],
4455 sizeof(early_node_map[j]));
4456 j = nr_nodemap_entries - 1;
4457 memset(&early_node_map[j], 0, sizeof(early_node_map[j]));
4458 nr_nodemap_entries--;
4463 * remove_all_active_ranges - Remove all currently registered regions
4465 * During discovery, it may be found that a table like SRAT is invalid
4466 * and an alternative discovery method must be used. This function removes
4467 * all currently registered regions.
4469 void __init remove_all_active_ranges(void)
4471 memset(early_node_map, 0, sizeof(early_node_map));
4472 nr_nodemap_entries = 0;
4475 /* Compare two active node_active_regions */
4476 static int __init cmp_node_active_region(const void *a, const void *b)
4478 struct node_active_region *arange = (struct node_active_region *)a;
4479 struct node_active_region *brange = (struct node_active_region *)b;
4481 /* Done this way to avoid overflows */
4482 if (arange->start_pfn > brange->start_pfn)
4484 if (arange->start_pfn < brange->start_pfn)
4490 /* sort the node_map by start_pfn */
4491 void __init sort_node_map(void)
4493 sort(early_node_map, (size_t)nr_nodemap_entries,
4494 sizeof(struct node_active_region),
4495 cmp_node_active_region, NULL);
4498 /* Find the lowest pfn for a node */
4499 static unsigned long __init find_min_pfn_for_node(int nid)
4502 unsigned long min_pfn = ULONG_MAX;
4504 /* Assuming a sorted map, the first range found has the starting pfn */
4505 for_each_active_range_index_in_nid(i, nid)
4506 min_pfn = min(min_pfn, early_node_map[i].start_pfn);
4508 if (min_pfn == ULONG_MAX) {
4510 "Could not find start_pfn for node %d\n", nid);
4518 * find_min_pfn_with_active_regions - Find the minimum PFN registered
4520 * It returns the minimum PFN based on information provided via
4521 * add_active_range().
4523 unsigned long __init find_min_pfn_with_active_regions(void)
4525 return find_min_pfn_for_node(MAX_NUMNODES);
4529 * early_calculate_totalpages()
4530 * Sum pages in active regions for movable zone.
4531 * Populate N_HIGH_MEMORY for calculating usable_nodes.
4533 static unsigned long __init early_calculate_totalpages(void)
4536 unsigned long totalpages = 0;
4538 for (i = 0; i < nr_nodemap_entries; i++) {
4539 unsigned long pages = early_node_map[i].end_pfn -
4540 early_node_map[i].start_pfn;
4541 totalpages += pages;
4543 node_set_state(early_node_map[i].nid, N_HIGH_MEMORY);
4549 * Find the PFN the Movable zone begins in each node. Kernel memory
4550 * is spread evenly between nodes as long as the nodes have enough
4551 * memory. When they don't, some nodes will have more kernelcore than
4554 static void __init find_zone_movable_pfns_for_nodes(unsigned long *movable_pfn)
4557 unsigned long usable_startpfn;
4558 unsigned long kernelcore_node, kernelcore_remaining;
4559 /* save the state before borrow the nodemask */
4560 nodemask_t saved_node_state = node_states[N_HIGH_MEMORY];
4561 unsigned long totalpages = early_calculate_totalpages();
4562 int usable_nodes = nodes_weight(node_states[N_HIGH_MEMORY]);
4565 * If movablecore was specified, calculate what size of
4566 * kernelcore that corresponds so that memory usable for
4567 * any allocation type is evenly spread. If both kernelcore
4568 * and movablecore are specified, then the value of kernelcore
4569 * will be used for required_kernelcore if it's greater than
4570 * what movablecore would have allowed.
4572 if (required_movablecore) {
4573 unsigned long corepages;
4576 * Round-up so that ZONE_MOVABLE is at least as large as what
4577 * was requested by the user
4579 required_movablecore =
4580 roundup(required_movablecore, MAX_ORDER_NR_PAGES);
4581 corepages = totalpages - required_movablecore;
4583 required_kernelcore = max(required_kernelcore, corepages);
4586 /* If kernelcore was not specified, there is no ZONE_MOVABLE */
4587 if (!required_kernelcore)
4590 /* usable_startpfn is the lowest possible pfn ZONE_MOVABLE can be at */
4591 find_usable_zone_for_movable();
4592 usable_startpfn = arch_zone_lowest_possible_pfn[movable_zone];
4595 /* Spread kernelcore memory as evenly as possible throughout nodes */
4596 kernelcore_node = required_kernelcore / usable_nodes;
4597 for_each_node_state(nid, N_HIGH_MEMORY) {
4599 * Recalculate kernelcore_node if the division per node
4600 * now exceeds what is necessary to satisfy the requested
4601 * amount of memory for the kernel
4603 if (required_kernelcore < kernelcore_node)
4604 kernelcore_node = required_kernelcore / usable_nodes;
4607 * As the map is walked, we track how much memory is usable
4608 * by the kernel using kernelcore_remaining. When it is
4609 * 0, the rest of the node is usable by ZONE_MOVABLE
4611 kernelcore_remaining = kernelcore_node;
4613 /* Go through each range of PFNs within this node */
4614 for_each_active_range_index_in_nid(i, nid) {
4615 unsigned long start_pfn, end_pfn;
4616 unsigned long size_pages;
4618 start_pfn = max(early_node_map[i].start_pfn,
4619 zone_movable_pfn[nid]);
4620 end_pfn = early_node_map[i].end_pfn;
4621 if (start_pfn >= end_pfn)
4624 /* Account for what is only usable for kernelcore */
4625 if (start_pfn < usable_startpfn) {
4626 unsigned long kernel_pages;
4627 kernel_pages = min(end_pfn, usable_startpfn)
4630 kernelcore_remaining -= min(kernel_pages,
4631 kernelcore_remaining);
4632 required_kernelcore -= min(kernel_pages,
4633 required_kernelcore);
4635 /* Continue if range is now fully accounted */
4636 if (end_pfn <= usable_startpfn) {
4639 * Push zone_movable_pfn to the end so
4640 * that if we have to rebalance
4641 * kernelcore across nodes, we will
4642 * not double account here
4644 zone_movable_pfn[nid] = end_pfn;
4647 start_pfn = usable_startpfn;
4651 * The usable PFN range for ZONE_MOVABLE is from
4652 * start_pfn->end_pfn. Calculate size_pages as the
4653 * number of pages used as kernelcore
4655 size_pages = end_pfn - start_pfn;
4656 if (size_pages > kernelcore_remaining)
4657 size_pages = kernelcore_remaining;
4658 zone_movable_pfn[nid] = start_pfn + size_pages;
4661 * Some kernelcore has been met, update counts and
4662 * break if the kernelcore for this node has been
4665 required_kernelcore -= min(required_kernelcore,
4667 kernelcore_remaining -= size_pages;
4668 if (!kernelcore_remaining)
4674 * If there is still required_kernelcore, we do another pass with one
4675 * less node in the count. This will push zone_movable_pfn[nid] further
4676 * along on the nodes that still have memory until kernelcore is
4680 if (usable_nodes && required_kernelcore > usable_nodes)
4683 /* Align start of ZONE_MOVABLE on all nids to MAX_ORDER_NR_PAGES */
4684 for (nid = 0; nid < MAX_NUMNODES; nid++)
4685 zone_movable_pfn[nid] =
4686 roundup(zone_movable_pfn[nid], MAX_ORDER_NR_PAGES);
4689 /* restore the node_state */
4690 node_states[N_HIGH_MEMORY] = saved_node_state;
4693 /* Any regular memory on that node ? */
4694 static void check_for_regular_memory(pg_data_t *pgdat)
4696 #ifdef CONFIG_HIGHMEM
4697 enum zone_type zone_type;
4699 for (zone_type = 0; zone_type <= ZONE_NORMAL; zone_type++) {
4700 struct zone *zone = &pgdat->node_zones[zone_type];
4701 if (zone->present_pages)
4702 node_set_state(zone_to_nid(zone), N_NORMAL_MEMORY);
4708 * free_area_init_nodes - Initialise all pg_data_t and zone data
4709 * @max_zone_pfn: an array of max PFNs for each zone
4711 * This will call free_area_init_node() for each active node in the system.
4712 * Using the page ranges provided by add_active_range(), the size of each
4713 * zone in each node and their holes is calculated. If the maximum PFN
4714 * between two adjacent zones match, it is assumed that the zone is empty.
4715 * For example, if arch_max_dma_pfn == arch_max_dma32_pfn, it is assumed
4716 * that arch_max_dma32_pfn has no pages. It is also assumed that a zone
4717 * starts where the previous one ended. For example, ZONE_DMA32 starts
4718 * at arch_max_dma_pfn.
4720 void __init free_area_init_nodes(unsigned long *max_zone_pfn)
4725 /* Sort early_node_map as initialisation assumes it is sorted */
4728 /* Record where the zone boundaries are */
4729 memset(arch_zone_lowest_possible_pfn, 0,
4730 sizeof(arch_zone_lowest_possible_pfn));
4731 memset(arch_zone_highest_possible_pfn, 0,
4732 sizeof(arch_zone_highest_possible_pfn));
4733 arch_zone_lowest_possible_pfn[0] = find_min_pfn_with_active_regions();
4734 arch_zone_highest_possible_pfn[0] = max_zone_pfn[0];
4735 for (i = 1; i < MAX_NR_ZONES; i++) {
4736 if (i == ZONE_MOVABLE)
4738 arch_zone_lowest_possible_pfn[i] =
4739 arch_zone_highest_possible_pfn[i-1];
4740 arch_zone_highest_possible_pfn[i] =
4741 max(max_zone_pfn[i], arch_zone_lowest_possible_pfn[i]);
4743 arch_zone_lowest_possible_pfn[ZONE_MOVABLE] = 0;
4744 arch_zone_highest_possible_pfn[ZONE_MOVABLE] = 0;
4746 /* Find the PFNs that ZONE_MOVABLE begins at in each node */
4747 memset(zone_movable_pfn, 0, sizeof(zone_movable_pfn));
4748 find_zone_movable_pfns_for_nodes(zone_movable_pfn);
4750 /* Print out the zone ranges */
4751 printk("Zone PFN ranges:\n");
4752 for (i = 0; i < MAX_NR_ZONES; i++) {
4753 if (i == ZONE_MOVABLE)
4755 printk(" %-8s ", zone_names[i]);
4756 if (arch_zone_lowest_possible_pfn[i] ==
4757 arch_zone_highest_possible_pfn[i])
4760 printk("%0#10lx -> %0#10lx\n",
4761 arch_zone_lowest_possible_pfn[i],
4762 arch_zone_highest_possible_pfn[i]);
4765 /* Print out the PFNs ZONE_MOVABLE begins at in each node */
4766 printk("Movable zone start PFN for each node\n");
4767 for (i = 0; i < MAX_NUMNODES; i++) {
4768 if (zone_movable_pfn[i])
4769 printk(" Node %d: %lu\n", i, zone_movable_pfn[i]);
4772 /* Print out the early_node_map[] */
4773 printk("early_node_map[%d] active PFN ranges\n", nr_nodemap_entries);
4774 for (i = 0; i < nr_nodemap_entries; i++)
4775 printk(" %3d: %0#10lx -> %0#10lx\n", early_node_map[i].nid,
4776 early_node_map[i].start_pfn,
4777 early_node_map[i].end_pfn);
4779 /* Initialise every node */
4780 mminit_verify_pageflags_layout();
4781 setup_nr_node_ids();
4782 for_each_online_node(nid) {
4783 pg_data_t *pgdat = NODE_DATA(nid);
4784 free_area_init_node(nid, NULL,
4785 find_min_pfn_for_node(nid), NULL);
4787 /* Any memory on that node */
4788 if (pgdat->node_present_pages)
4789 node_set_state(nid, N_HIGH_MEMORY);
4790 check_for_regular_memory(pgdat);
4794 static int __init cmdline_parse_core(char *p, unsigned long *core)
4796 unsigned long long coremem;
4800 coremem = memparse(p, &p);
4801 *core = coremem >> PAGE_SHIFT;
4803 /* Paranoid check that UL is enough for the coremem value */
4804 WARN_ON((coremem >> PAGE_SHIFT) > ULONG_MAX);
4810 * kernelcore=size sets the amount of memory for use for allocations that
4811 * cannot be reclaimed or migrated.
4813 static int __init cmdline_parse_kernelcore(char *p)
4815 return cmdline_parse_core(p, &required_kernelcore);
4819 * movablecore=size sets the amount of memory for use for allocations that
4820 * can be reclaimed or migrated.
4822 static int __init cmdline_parse_movablecore(char *p)
4824 return cmdline_parse_core(p, &required_movablecore);
4827 early_param("kernelcore", cmdline_parse_kernelcore);
4828 early_param("movablecore", cmdline_parse_movablecore);
4830 #endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
4833 * set_dma_reserve - set the specified number of pages reserved in the first zone
4834 * @new_dma_reserve: The number of pages to mark reserved
4836 * The per-cpu batchsize and zone watermarks are determined by present_pages.
4837 * In the DMA zone, a significant percentage may be consumed by kernel image
4838 * and other unfreeable allocations which can skew the watermarks badly. This
4839 * function may optionally be used to account for unfreeable pages in the
4840 * first zone (e.g., ZONE_DMA). The effect will be lower watermarks and
4841 * smaller per-cpu batchsize.
4843 void __init set_dma_reserve(unsigned long new_dma_reserve)
4845 dma_reserve = new_dma_reserve;
4848 void __init free_area_init(unsigned long *zones_size)
4850 free_area_init_node(0, zones_size,
4851 __pa(PAGE_OFFSET) >> PAGE_SHIFT, NULL);
4854 static int page_alloc_cpu_notify(struct notifier_block *self,
4855 unsigned long action, void *hcpu)
4857 int cpu = (unsigned long)hcpu;
4859 if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) {
4863 * Spill the event counters of the dead processor
4864 * into the current processors event counters.
4865 * This artificially elevates the count of the current
4868 vm_events_fold_cpu(cpu);
4871 * Zero the differential counters of the dead processor
4872 * so that the vm statistics are consistent.
4874 * This is only okay since the processor is dead and cannot
4875 * race with what we are doing.
4877 refresh_cpu_vm_stats(cpu);
4882 void __init page_alloc_init(void)
4884 hotcpu_notifier(page_alloc_cpu_notify, 0);
4888 * calculate_totalreserve_pages - called when sysctl_lower_zone_reserve_ratio
4889 * or min_free_kbytes changes.
4891 static void calculate_totalreserve_pages(void)
4893 struct pglist_data *pgdat;
4894 unsigned long reserve_pages = 0;
4895 enum zone_type i, j;
4897 for_each_online_pgdat(pgdat) {
4898 for (i = 0; i < MAX_NR_ZONES; i++) {
4899 struct zone *zone = pgdat->node_zones + i;
4900 unsigned long max = 0;
4902 /* Find valid and maximum lowmem_reserve in the zone */
4903 for (j = i; j < MAX_NR_ZONES; j++) {
4904 if (zone->lowmem_reserve[j] > max)
4905 max = zone->lowmem_reserve[j];
4908 /* we treat the high watermark as reserved pages. */
4909 max += high_wmark_pages(zone);
4911 if (max > zone->present_pages)
4912 max = zone->present_pages;
4913 reserve_pages += max;
4916 totalreserve_pages = reserve_pages;
4920 * setup_per_zone_lowmem_reserve - called whenever
4921 * sysctl_lower_zone_reserve_ratio changes. Ensures that each zone
4922 * has a correct pages reserved value, so an adequate number of
4923 * pages are left in the zone after a successful __alloc_pages().
4925 static void setup_per_zone_lowmem_reserve(void)
4927 struct pglist_data *pgdat;
4928 enum zone_type j, idx;
4930 for_each_online_pgdat(pgdat) {
4931 for (j = 0; j < MAX_NR_ZONES; j++) {
4932 struct zone *zone = pgdat->node_zones + j;
4933 unsigned long present_pages = zone->present_pages;
4935 zone->lowmem_reserve[j] = 0;
4939 struct zone *lower_zone;
4943 if (sysctl_lowmem_reserve_ratio[idx] < 1)
4944 sysctl_lowmem_reserve_ratio[idx] = 1;
4946 lower_zone = pgdat->node_zones + idx;
4947 lower_zone->lowmem_reserve[j] = present_pages /
4948 sysctl_lowmem_reserve_ratio[idx];
4949 present_pages += lower_zone->present_pages;
4954 /* update totalreserve_pages */
4955 calculate_totalreserve_pages();
4959 * setup_per_zone_wmarks - called when min_free_kbytes changes
4960 * or when memory is hot-{added|removed}
4962 * Ensures that the watermark[min,low,high] values for each zone are set
4963 * correctly with respect to min_free_kbytes.
4965 void setup_per_zone_wmarks(void)
4967 unsigned long pages_min = min_free_kbytes >> (PAGE_SHIFT - 10);
4968 unsigned long lowmem_pages = 0;
4970 unsigned long flags;
4972 /* Calculate total number of !ZONE_HIGHMEM pages */
4973 for_each_zone(zone) {
4974 if (!is_highmem(zone))
4975 lowmem_pages += zone->present_pages;
4978 for_each_zone(zone) {
4981 spin_lock_irqsave(&zone->lock, flags);
4982 tmp = (u64)pages_min * zone->present_pages;
4983 do_div(tmp, lowmem_pages);
4984 if (is_highmem(zone)) {
4986 * __GFP_HIGH and PF_MEMALLOC allocations usually don't
4987 * need highmem pages, so cap pages_min to a small
4990 * The WMARK_HIGH-WMARK_LOW and (WMARK_LOW-WMARK_MIN)
4991 * deltas controls asynch page reclaim, and so should
4992 * not be capped for highmem.
4996 min_pages = zone->present_pages / 1024;
4997 if (min_pages < SWAP_CLUSTER_MAX)
4998 min_pages = SWAP_CLUSTER_MAX;
4999 if (min_pages > 128)
5001 zone->watermark[WMARK_MIN] = min_pages;
5004 * If it's a lowmem zone, reserve a number of pages
5005 * proportionate to the zone's size.
5007 zone->watermark[WMARK_MIN] = tmp;
5010 zone->watermark[WMARK_LOW] = min_wmark_pages(zone) + (tmp >> 2);
5011 zone->watermark[WMARK_HIGH] = min_wmark_pages(zone) + (tmp >> 1);
5012 setup_zone_migrate_reserve(zone);
5013 spin_unlock_irqrestore(&zone->lock, flags);
5016 /* update totalreserve_pages */
5017 calculate_totalreserve_pages();
5021 * The inactive anon list should be small enough that the VM never has to
5022 * do too much work, but large enough that each inactive page has a chance
5023 * to be referenced again before it is swapped out.
5025 * The inactive_anon ratio is the target ratio of ACTIVE_ANON to
5026 * INACTIVE_ANON pages on this zone's LRU, maintained by the
5027 * pageout code. A zone->inactive_ratio of 3 means 3:1 or 25% of
5028 * the anonymous pages are kept on the inactive list.
5031 * memory ratio inactive anon
5032 * -------------------------------------
5041 void calculate_zone_inactive_ratio(struct zone *zone)
5043 unsigned int gb, ratio;
5045 /* Zone size in gigabytes */
5046 gb = zone->present_pages >> (30 - PAGE_SHIFT);
5048 ratio = int_sqrt(10 * gb);
5052 zone->inactive_ratio = ratio;
5055 static void __init setup_per_zone_inactive_ratio(void)
5060 calculate_zone_inactive_ratio(zone);
5064 * Initialise min_free_kbytes.
5066 * For small machines we want it small (128k min). For large machines
5067 * we want it large (64MB max). But it is not linear, because network
5068 * bandwidth does not increase linearly with machine size. We use
5070 * min_free_kbytes = 4 * sqrt(lowmem_kbytes), for better accuracy:
5071 * min_free_kbytes = sqrt(lowmem_kbytes * 16)
5087 static int __init init_per_zone_wmark_min(void)
5089 unsigned long lowmem_kbytes;
5091 lowmem_kbytes = nr_free_buffer_pages() * (PAGE_SIZE >> 10);
5093 min_free_kbytes = int_sqrt(lowmem_kbytes * 16);
5094 if (min_free_kbytes < 128)
5095 min_free_kbytes = 128;
5096 if (min_free_kbytes > 65536)
5097 min_free_kbytes = 65536;
5098 setup_per_zone_wmarks();
5099 setup_per_zone_lowmem_reserve();
5100 setup_per_zone_inactive_ratio();
5103 module_init(init_per_zone_wmark_min)
5106 * min_free_kbytes_sysctl_handler - just a wrapper around proc_dointvec() so
5107 * that we can call two helper functions whenever min_free_kbytes
5110 int min_free_kbytes_sysctl_handler(ctl_table *table, int write,
5111 void __user *buffer, size_t *length, loff_t *ppos)
5113 proc_dointvec(table, write, buffer, length, ppos);
5115 setup_per_zone_wmarks();
5120 int sysctl_min_unmapped_ratio_sysctl_handler(ctl_table *table, int write,
5121 void __user *buffer, size_t *length, loff_t *ppos)
5126 rc = proc_dointvec_minmax(table, write, buffer, length, ppos);
5131 zone->min_unmapped_pages = (zone->present_pages *
5132 sysctl_min_unmapped_ratio) / 100;
5136 int sysctl_min_slab_ratio_sysctl_handler(ctl_table *table, int write,
5137 void __user *buffer, size_t *length, loff_t *ppos)
5142 rc = proc_dointvec_minmax(table, write, buffer, length, ppos);
5147 zone->min_slab_pages = (zone->present_pages *
5148 sysctl_min_slab_ratio) / 100;
5154 * lowmem_reserve_ratio_sysctl_handler - just a wrapper around
5155 * proc_dointvec() so that we can call setup_per_zone_lowmem_reserve()
5156 * whenever sysctl_lowmem_reserve_ratio changes.
5158 * The reserve ratio obviously has absolutely no relation with the
5159 * minimum watermarks. The lowmem reserve ratio can only make sense
5160 * if in function of the boot time zone sizes.
5162 int lowmem_reserve_ratio_sysctl_handler(ctl_table *table, int write,
5163 void __user *buffer, size_t *length, loff_t *ppos)
5165 proc_dointvec_minmax(table, write, buffer, length, ppos);
5166 setup_per_zone_lowmem_reserve();
5171 * percpu_pagelist_fraction - changes the pcp->high for each zone on each
5172 * cpu. It is the fraction of total pages in each zone that a hot per cpu pagelist
5173 * can have before it gets flushed back to buddy allocator.
5176 int percpu_pagelist_fraction_sysctl_handler(ctl_table *table, int write,
5177 void __user *buffer, size_t *length, loff_t *ppos)
5183 ret = proc_dointvec_minmax(table, write, buffer, length, ppos);
5184 if (!write || (ret == -EINVAL))
5186 for_each_populated_zone(zone) {
5187 for_each_possible_cpu(cpu) {
5189 high = zone->present_pages / percpu_pagelist_fraction;
5190 setup_pagelist_highmark(
5191 per_cpu_ptr(zone->pageset, cpu), high);
5197 int hashdist = HASHDIST_DEFAULT;
5200 static int __init set_hashdist(char *str)
5204 hashdist = simple_strtoul(str, &str, 0);
5207 __setup("hashdist=", set_hashdist);
5211 * allocate a large system hash table from bootmem
5212 * - it is assumed that the hash table must contain an exact power-of-2
5213 * quantity of entries
5214 * - limit is the number of hash buckets, not the total allocation size
5216 void *__init alloc_large_system_hash(const char *tablename,
5217 unsigned long bucketsize,
5218 unsigned long numentries,
5221 unsigned int *_hash_shift,
5222 unsigned int *_hash_mask,
5223 unsigned long limit)
5225 unsigned long long max = limit;
5226 unsigned long log2qty, size;
5229 /* allow the kernel cmdline to have a say */
5231 /* round applicable memory size up to nearest megabyte */
5232 numentries = nr_kernel_pages;
5233 numentries += (1UL << (20 - PAGE_SHIFT)) - 1;
5234 numentries >>= 20 - PAGE_SHIFT;
5235 numentries <<= 20 - PAGE_SHIFT;
5237 /* limit to 1 bucket per 2^scale bytes of low memory */
5238 if (scale > PAGE_SHIFT)
5239 numentries >>= (scale - PAGE_SHIFT);
5241 numentries <<= (PAGE_SHIFT - scale);
5243 /* Make sure we've got at least a 0-order allocation.. */
5244 if (unlikely(flags & HASH_SMALL)) {
5245 /* Makes no sense without HASH_EARLY */
5246 WARN_ON(!(flags & HASH_EARLY));
5247 if (!(numentries >> *_hash_shift)) {
5248 numentries = 1UL << *_hash_shift;
5249 BUG_ON(!numentries);
5251 } else if (unlikely((numentries * bucketsize) < PAGE_SIZE))
5252 numentries = PAGE_SIZE / bucketsize;
5254 numentries = roundup_pow_of_two(numentries);
5256 /* limit allocation size to 1/16 total memory by default */
5258 max = ((unsigned long long)nr_all_pages << PAGE_SHIFT) >> 4;
5259 do_div(max, bucketsize);
5262 if (numentries > max)
5265 log2qty = ilog2(numentries);
5268 size = bucketsize << log2qty;
5269 if (flags & HASH_EARLY)
5270 table = alloc_bootmem_nopanic(size);
5272 table = __vmalloc(size, GFP_ATOMIC, PAGE_KERNEL);
5275 * If bucketsize is not a power-of-two, we may free
5276 * some pages at the end of hash table which
5277 * alloc_pages_exact() automatically does
5279 if (get_order(size) < MAX_ORDER) {
5280 table = alloc_pages_exact(size, GFP_ATOMIC);
5281 kmemleak_alloc(table, size, 1, GFP_ATOMIC);
5284 } while (!table && size > PAGE_SIZE && --log2qty);
5287 panic("Failed to allocate %s hash table\n", tablename);
5289 printk(KERN_INFO "%s hash table entries: %ld (order: %d, %lu bytes)\n",
5292 ilog2(size) - PAGE_SHIFT,
5296 *_hash_shift = log2qty;
5298 *_hash_mask = (1 << log2qty) - 1;
5303 /* Return a pointer to the bitmap storing bits affecting a block of pages */
5304 static inline unsigned long *get_pageblock_bitmap(struct zone *zone,
5307 #ifdef CONFIG_SPARSEMEM
5308 return __pfn_to_section(pfn)->pageblock_flags;
5310 return zone->pageblock_flags;
5311 #endif /* CONFIG_SPARSEMEM */
5314 static inline int pfn_to_bitidx(struct zone *zone, unsigned long pfn)
5316 #ifdef CONFIG_SPARSEMEM
5317 pfn &= (PAGES_PER_SECTION-1);
5318 return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS;
5320 pfn = pfn - zone->zone_start_pfn;
5321 return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS;
5322 #endif /* CONFIG_SPARSEMEM */
5326 * get_pageblock_flags_group - Return the requested group of flags for the pageblock_nr_pages block of pages
5327 * @page: The page within the block of interest
5328 * @start_bitidx: The first bit of interest to retrieve
5329 * @end_bitidx: The last bit of interest
5330 * returns pageblock_bits flags
5332 unsigned long get_pageblock_flags_group(struct page *page,
5333 int start_bitidx, int end_bitidx)
5336 unsigned long *bitmap;
5337 unsigned long pfn, bitidx;
5338 unsigned long flags = 0;
5339 unsigned long value = 1;
5341 zone = page_zone(page);
5342 pfn = page_to_pfn(page);
5343 bitmap = get_pageblock_bitmap(zone, pfn);
5344 bitidx = pfn_to_bitidx(zone, pfn);
5346 for (; start_bitidx <= end_bitidx; start_bitidx++, value <<= 1)
5347 if (test_bit(bitidx + start_bitidx, bitmap))
5354 * set_pageblock_flags_group - Set the requested group of flags for a pageblock_nr_pages block of pages
5355 * @page: The page within the block of interest
5356 * @start_bitidx: The first bit of interest
5357 * @end_bitidx: The last bit of interest
5358 * @flags: The flags to set
5360 void set_pageblock_flags_group(struct page *page, unsigned long flags,
5361 int start_bitidx, int end_bitidx)
5364 unsigned long *bitmap;
5365 unsigned long pfn, bitidx;
5366 unsigned long value = 1;
5368 zone = page_zone(page);
5369 pfn = page_to_pfn(page);
5370 bitmap = get_pageblock_bitmap(zone, pfn);
5371 bitidx = pfn_to_bitidx(zone, pfn);
5372 VM_BUG_ON(pfn < zone->zone_start_pfn);
5373 VM_BUG_ON(pfn >= zone->zone_start_pfn + zone->spanned_pages);
5375 for (; start_bitidx <= end_bitidx; start_bitidx++, value <<= 1)
5377 __set_bit(bitidx + start_bitidx, bitmap);
5379 __clear_bit(bitidx + start_bitidx, bitmap);
5383 * This is designed as sub function...plz see page_isolation.c also.
5384 * set/clear page block's type to be ISOLATE.
5385 * page allocater never alloc memory from ISOLATE block.
5389 __count_immobile_pages(struct zone *zone, struct page *page, int count)
5391 unsigned long pfn, iter, found;
5393 * For avoiding noise data, lru_add_drain_all() should be called
5394 * If ZONE_MOVABLE, the zone never contains immobile pages
5396 if (zone_idx(zone) == ZONE_MOVABLE)
5399 if (get_pageblock_migratetype(page) == MIGRATE_MOVABLE)
5402 pfn = page_to_pfn(page);
5403 for (found = 0, iter = 0; iter < pageblock_nr_pages; iter++) {
5404 unsigned long check = pfn + iter;
5406 if (!pfn_valid_within(check))
5409 page = pfn_to_page(check);
5410 if (!page_count(page)) {
5411 if (PageBuddy(page))
5412 iter += (1 << page_order(page)) - 1;
5418 * If there are RECLAIMABLE pages, we need to check it.
5419 * But now, memory offline itself doesn't call shrink_slab()
5420 * and it still to be fixed.
5423 * If the page is not RAM, page_count()should be 0.
5424 * we don't need more check. This is an _used_ not-movable page.
5426 * The problematic thing here is PG_reserved pages. PG_reserved
5427 * is set to both of a memory hole page and a _used_ kernel
5436 bool is_pageblock_removable_nolock(struct page *page)
5438 struct zone *zone = page_zone(page);
5439 return __count_immobile_pages(zone, page, 0);
5442 int set_migratetype_isolate(struct page *page)
5445 unsigned long flags, pfn;
5446 struct memory_isolate_notify arg;
5451 zone = page_zone(page);
5452 zone_idx = zone_idx(zone);
5454 spin_lock_irqsave(&zone->lock, flags);
5456 pfn = page_to_pfn(page);
5457 arg.start_pfn = pfn;
5458 arg.nr_pages = pageblock_nr_pages;
5459 arg.pages_found = 0;
5462 * It may be possible to isolate a pageblock even if the
5463 * migratetype is not MIGRATE_MOVABLE. The memory isolation
5464 * notifier chain is used by balloon drivers to return the
5465 * number of pages in a range that are held by the balloon
5466 * driver to shrink memory. If all the pages are accounted for
5467 * by balloons, are free, or on the LRU, isolation can continue.
5468 * Later, for example, when memory hotplug notifier runs, these
5469 * pages reported as "can be isolated" should be isolated(freed)
5470 * by the balloon driver through the memory notifier chain.
5472 notifier_ret = memory_isolate_notify(MEM_ISOLATE_COUNT, &arg);
5473 notifier_ret = notifier_to_errno(notifier_ret);
5477 * FIXME: Now, memory hotplug doesn't call shrink_slab() by itself.
5478 * We just check MOVABLE pages.
5480 if (__count_immobile_pages(zone, page, arg.pages_found))
5484 * immobile means "not-on-lru" paes. If immobile is larger than
5485 * removable-by-driver pages reported by notifier, we'll fail.
5490 set_pageblock_migratetype(page, MIGRATE_ISOLATE);
5491 move_freepages_block(zone, page, MIGRATE_ISOLATE);
5494 spin_unlock_irqrestore(&zone->lock, flags);
5500 void unset_migratetype_isolate(struct page *page)
5503 unsigned long flags;
5504 zone = page_zone(page);
5505 spin_lock_irqsave(&zone->lock, flags);
5506 if (get_pageblock_migratetype(page) != MIGRATE_ISOLATE)
5508 set_pageblock_migratetype(page, MIGRATE_MOVABLE);
5509 move_freepages_block(zone, page, MIGRATE_MOVABLE);
5511 spin_unlock_irqrestore(&zone->lock, flags);
5514 #ifdef CONFIG_MEMORY_HOTREMOVE
5516 * All pages in the range must be isolated before calling this.
5519 __offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
5525 unsigned long flags;
5526 /* find the first valid pfn */
5527 for (pfn = start_pfn; pfn < end_pfn; pfn++)
5532 zone = page_zone(pfn_to_page(pfn));
5533 spin_lock_irqsave(&zone->lock, flags);
5535 while (pfn < end_pfn) {
5536 if (!pfn_valid(pfn)) {
5540 page = pfn_to_page(pfn);
5541 BUG_ON(page_count(page));
5542 BUG_ON(!PageBuddy(page));
5543 order = page_order(page);
5544 #ifdef CONFIG_DEBUG_VM
5545 printk(KERN_INFO "remove from free list %lx %d %lx\n",
5546 pfn, 1 << order, end_pfn);
5548 list_del(&page->lru);
5549 rmv_page_order(page);
5550 zone->free_area[order].nr_free--;
5551 __mod_zone_page_state(zone, NR_FREE_PAGES,
5553 for (i = 0; i < (1 << order); i++)
5554 SetPageReserved((page+i));
5555 pfn += (1 << order);
5557 spin_unlock_irqrestore(&zone->lock, flags);
5561 #ifdef CONFIG_MEMORY_FAILURE
5562 bool is_free_buddy_page(struct page *page)
5564 struct zone *zone = page_zone(page);
5565 unsigned long pfn = page_to_pfn(page);
5566 unsigned long flags;
5569 spin_lock_irqsave(&zone->lock, flags);
5570 for (order = 0; order < MAX_ORDER; order++) {
5571 struct page *page_head = page - (pfn & ((1 << order) - 1));
5573 if (PageBuddy(page_head) && page_order(page_head) >= order)
5576 spin_unlock_irqrestore(&zone->lock, flags);
5578 return order < MAX_ORDER;
5582 static struct trace_print_flags pageflag_names[] = {
5583 {1UL << PG_locked, "locked" },
5584 {1UL << PG_error, "error" },
5585 {1UL << PG_referenced, "referenced" },
5586 {1UL << PG_uptodate, "uptodate" },
5587 {1UL << PG_dirty, "dirty" },
5588 {1UL << PG_lru, "lru" },
5589 {1UL << PG_active, "active" },
5590 {1UL << PG_slab, "slab" },
5591 {1UL << PG_owner_priv_1, "owner_priv_1" },
5592 {1UL << PG_arch_1, "arch_1" },
5593 {1UL << PG_reserved, "reserved" },
5594 {1UL << PG_private, "private" },
5595 {1UL << PG_private_2, "private_2" },
5596 {1UL << PG_writeback, "writeback" },
5597 #ifdef CONFIG_PAGEFLAGS_EXTENDED
5598 {1UL << PG_head, "head" },
5599 {1UL << PG_tail, "tail" },
5601 {1UL << PG_compound, "compound" },
5603 {1UL << PG_swapcache, "swapcache" },
5604 {1UL << PG_mappedtodisk, "mappedtodisk" },
5605 {1UL << PG_reclaim, "reclaim" },
5606 {1UL << PG_swapbacked, "swapbacked" },
5607 {1UL << PG_unevictable, "unevictable" },
5609 {1UL << PG_mlocked, "mlocked" },
5611 #ifdef CONFIG_ARCH_USES_PG_UNCACHED
5612 {1UL << PG_uncached, "uncached" },
5614 #ifdef CONFIG_MEMORY_FAILURE
5615 {1UL << PG_hwpoison, "hwpoison" },
5620 static void dump_page_flags(unsigned long flags)
5622 const char *delim = "";
5626 printk(KERN_ALERT "page flags: %#lx(", flags);
5628 /* remove zone id */
5629 flags &= (1UL << NR_PAGEFLAGS) - 1;
5631 for (i = 0; pageflag_names[i].name && flags; i++) {
5633 mask = pageflag_names[i].mask;
5634 if ((flags & mask) != mask)
5638 printk("%s%s", delim, pageflag_names[i].name);
5642 /* check for left over flags */
5644 printk("%s%#lx", delim, flags);
5649 void dump_page(struct page *page)
5652 "page:%p count:%d mapcount:%d mapping:%p index:%#lx\n",
5653 page, atomic_read(&page->_count), page_mapcount(page),
5654 page->mapping, page->index);
5655 dump_page_flags(page->flags);