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/compiler.h>
25 #include <linux/kernel.h>
26 #include <linux/kmemcheck.h>
27 #include <linux/module.h>
28 #include <linux/suspend.h>
29 #include <linux/pagevec.h>
30 #include <linux/blkdev.h>
31 #include <linux/slab.h>
32 #include <linux/oom.h>
33 #include <linux/notifier.h>
34 #include <linux/topology.h>
35 #include <linux/sysctl.h>
36 #include <linux/cpu.h>
37 #include <linux/cpuset.h>
38 #include <linux/memory_hotplug.h>
39 #include <linux/nodemask.h>
40 #include <linux/vmalloc.h>
41 #include <linux/mempolicy.h>
42 #include <linux/stop_machine.h>
43 #include <linux/sort.h>
44 #include <linux/pfn.h>
45 #include <linux/backing-dev.h>
46 #include <linux/fault-inject.h>
47 #include <linux/page-isolation.h>
48 #include <linux/page_cgroup.h>
49 #include <linux/debugobjects.h>
50 #include <linux/kmemleak.h>
51 #include <linux/memory.h>
52 #include <linux/compaction.h>
53 #include <trace/events/kmem.h>
54 #include <linux/ftrace_event.h>
56 #include <asm/tlbflush.h>
57 #include <asm/div64.h>
61 * Array of node states.
63 nodemask_t node_states
[NR_NODE_STATES
] __read_mostly
= {
64 [N_POSSIBLE
] = NODE_MASK_ALL
,
65 [N_ONLINE
] = { { [0] = 1UL } },
67 [N_NORMAL_MEMORY
] = { { [0] = 1UL } },
69 [N_HIGH_MEMORY
] = { { [0] = 1UL } },
71 [N_CPU
] = { { [0] = 1UL } },
74 EXPORT_SYMBOL(node_states
);
76 unsigned long totalram_pages __read_mostly
;
77 unsigned long totalreserve_pages __read_mostly
;
78 int percpu_pagelist_fraction
;
79 gfp_t gfp_allowed_mask __read_mostly
= GFP_BOOT_MASK
;
81 #ifdef CONFIG_PM_SLEEP
83 * The following functions are used by the suspend/hibernate code to temporarily
84 * change gfp_allowed_mask in order to avoid using I/O during memory allocations
85 * while devices are suspended. To avoid races with the suspend/hibernate code,
86 * they should always be called with pm_mutex held (gfp_allowed_mask also should
87 * only be modified with pm_mutex held, unless the suspend/hibernate code is
88 * guaranteed not to run in parallel with that modification).
90 void set_gfp_allowed_mask(gfp_t mask
)
92 WARN_ON(!mutex_is_locked(&pm_mutex
));
93 gfp_allowed_mask
= mask
;
96 gfp_t
clear_gfp_allowed_mask(gfp_t mask
)
98 gfp_t ret
= gfp_allowed_mask
;
100 WARN_ON(!mutex_is_locked(&pm_mutex
));
101 gfp_allowed_mask
&= ~mask
;
104 #endif /* CONFIG_PM_SLEEP */
106 #ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
107 int pageblock_order __read_mostly
;
110 static void __free_pages_ok(struct page
*page
, unsigned int order
);
113 * results with 256, 32 in the lowmem_reserve sysctl:
114 * 1G machine -> (16M dma, 800M-16M normal, 1G-800M high)
115 * 1G machine -> (16M dma, 784M normal, 224M high)
116 * NORMAL allocation will leave 784M/256 of ram reserved in the ZONE_DMA
117 * HIGHMEM allocation will leave 224M/32 of ram reserved in ZONE_NORMAL
118 * HIGHMEM allocation will (224M+784M)/256 of ram reserved in ZONE_DMA
120 * TBD: should special case ZONE_DMA32 machines here - in those we normally
121 * don't need any ZONE_NORMAL reservation
123 int sysctl_lowmem_reserve_ratio
[MAX_NR_ZONES
-1] = {
124 #ifdef CONFIG_ZONE_DMA
127 #ifdef CONFIG_ZONE_DMA32
130 #ifdef CONFIG_HIGHMEM
136 EXPORT_SYMBOL(totalram_pages
);
138 static char * const zone_names
[MAX_NR_ZONES
] = {
139 #ifdef CONFIG_ZONE_DMA
142 #ifdef CONFIG_ZONE_DMA32
146 #ifdef CONFIG_HIGHMEM
152 int min_free_kbytes
= 1024;
154 static unsigned long __meminitdata nr_kernel_pages
;
155 static unsigned long __meminitdata nr_all_pages
;
156 static unsigned long __meminitdata dma_reserve
;
158 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
160 * MAX_ACTIVE_REGIONS determines the maximum number of distinct
161 * ranges of memory (RAM) that may be registered with add_active_range().
162 * Ranges passed to add_active_range() will be merged if possible
163 * so the number of times add_active_range() can be called is
164 * related to the number of nodes and the number of holes
166 #ifdef CONFIG_MAX_ACTIVE_REGIONS
167 /* Allow an architecture to set MAX_ACTIVE_REGIONS to save memory */
168 #define MAX_ACTIVE_REGIONS CONFIG_MAX_ACTIVE_REGIONS
170 #if MAX_NUMNODES >= 32
171 /* If there can be many nodes, allow up to 50 holes per node */
172 #define MAX_ACTIVE_REGIONS (MAX_NUMNODES*50)
174 /* By default, allow up to 256 distinct regions */
175 #define MAX_ACTIVE_REGIONS 256
179 static struct node_active_region __meminitdata early_node_map
[MAX_ACTIVE_REGIONS
];
180 static int __meminitdata nr_nodemap_entries
;
181 static unsigned long __meminitdata arch_zone_lowest_possible_pfn
[MAX_NR_ZONES
];
182 static unsigned long __meminitdata arch_zone_highest_possible_pfn
[MAX_NR_ZONES
];
183 static unsigned long __initdata required_kernelcore
;
184 static unsigned long __initdata required_movablecore
;
185 static unsigned long __meminitdata zone_movable_pfn
[MAX_NUMNODES
];
187 /* movable_zone is the "real" zone pages in ZONE_MOVABLE are taken from */
189 EXPORT_SYMBOL(movable_zone
);
190 #endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
193 int nr_node_ids __read_mostly
= MAX_NUMNODES
;
194 int nr_online_nodes __read_mostly
= 1;
195 EXPORT_SYMBOL(nr_node_ids
);
196 EXPORT_SYMBOL(nr_online_nodes
);
199 int page_group_by_mobility_disabled __read_mostly
;
201 static void set_pageblock_migratetype(struct page
*page
, int migratetype
)
204 if (unlikely(page_group_by_mobility_disabled
))
205 migratetype
= MIGRATE_UNMOVABLE
;
207 set_pageblock_flags_group(page
, (unsigned long)migratetype
,
208 PB_migrate
, PB_migrate_end
);
211 bool oom_killer_disabled __read_mostly
;
213 #ifdef CONFIG_DEBUG_VM
214 static int page_outside_zone_boundaries(struct zone
*zone
, struct page
*page
)
218 unsigned long pfn
= page_to_pfn(page
);
221 seq
= zone_span_seqbegin(zone
);
222 if (pfn
>= zone
->zone_start_pfn
+ zone
->spanned_pages
)
224 else if (pfn
< zone
->zone_start_pfn
)
226 } while (zone_span_seqretry(zone
, seq
));
231 static int page_is_consistent(struct zone
*zone
, struct page
*page
)
233 if (!pfn_valid_within(page_to_pfn(page
)))
235 if (zone
!= page_zone(page
))
241 * Temporary debugging check for pages not lying within a given zone.
243 static int bad_range(struct zone
*zone
, struct page
*page
)
245 if (page_outside_zone_boundaries(zone
, page
))
247 if (!page_is_consistent(zone
, page
))
253 static inline int bad_range(struct zone
*zone
, struct page
*page
)
259 static void bad_page(struct page
*page
)
261 static unsigned long resume
;
262 static unsigned long nr_shown
;
263 static unsigned long nr_unshown
;
265 /* Don't complain about poisoned pages */
266 if (PageHWPoison(page
)) {
267 __ClearPageBuddy(page
);
272 * Allow a burst of 60 reports, then keep quiet for that minute;
273 * or allow a steady drip of one report per second.
275 if (nr_shown
== 60) {
276 if (time_before(jiffies
, resume
)) {
282 "BUG: Bad page state: %lu messages suppressed\n",
289 resume
= jiffies
+ 60 * HZ
;
291 printk(KERN_ALERT
"BUG: Bad page state in process %s pfn:%05lx\n",
292 current
->comm
, page_to_pfn(page
));
297 /* Leave bad fields for debug, except PageBuddy could make trouble */
298 __ClearPageBuddy(page
);
299 add_taint(TAINT_BAD_PAGE
);
303 * Higher-order pages are called "compound pages". They are structured thusly:
305 * The first PAGE_SIZE page is called the "head page".
307 * The remaining PAGE_SIZE pages are called "tail pages".
309 * All pages have PG_compound set. All pages have their ->private pointing at
310 * the head page (even the head page has this).
312 * The first tail page's ->lru.next holds the address of the compound page's
313 * put_page() function. Its ->lru.prev holds the order of allocation.
314 * This usage means that zero-order pages may not be compound.
317 static void free_compound_page(struct page
*page
)
319 __free_pages_ok(page
, compound_order(page
));
322 void prep_compound_page(struct page
*page
, unsigned long order
)
325 int nr_pages
= 1 << order
;
327 set_compound_page_dtor(page
, free_compound_page
);
328 set_compound_order(page
, order
);
330 for (i
= 1; i
< nr_pages
; i
++) {
331 struct page
*p
= page
+ i
;
334 p
->first_page
= page
;
338 static int destroy_compound_page(struct page
*page
, unsigned long order
)
341 int nr_pages
= 1 << order
;
344 if (unlikely(compound_order(page
) != order
) ||
345 unlikely(!PageHead(page
))) {
350 __ClearPageHead(page
);
352 for (i
= 1; i
< nr_pages
; i
++) {
353 struct page
*p
= page
+ i
;
355 if (unlikely(!PageTail(p
) || (p
->first_page
!= page
))) {
365 static inline void prep_zero_page(struct page
*page
, int order
, gfp_t gfp_flags
)
370 * clear_highpage() will use KM_USER0, so it's a bug to use __GFP_ZERO
371 * and __GFP_HIGHMEM from hard or soft interrupt context.
373 VM_BUG_ON((gfp_flags
& __GFP_HIGHMEM
) && in_interrupt());
374 for (i
= 0; i
< (1 << order
); i
++)
375 clear_highpage(page
+ i
);
378 static inline void set_page_order(struct page
*page
, int order
)
380 set_page_private(page
, order
);
381 __SetPageBuddy(page
);
384 static inline void rmv_page_order(struct page
*page
)
386 __ClearPageBuddy(page
);
387 set_page_private(page
, 0);
391 * Locate the struct page for both the matching buddy in our
392 * pair (buddy1) and the combined O(n+1) page they form (page).
394 * 1) Any buddy B1 will have an order O twin B2 which satisfies
395 * the following equation:
397 * For example, if the starting buddy (buddy2) is #8 its order
399 * B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10
401 * 2) Any buddy B will have an order O+1 parent P which
402 * satisfies the following equation:
405 * Assumption: *_mem_map is contiguous at least up to MAX_ORDER
407 static inline struct page
*
408 __page_find_buddy(struct page
*page
, unsigned long page_idx
, unsigned int order
)
410 unsigned long buddy_idx
= page_idx
^ (1 << order
);
412 return page
+ (buddy_idx
- page_idx
);
415 static inline unsigned long
416 __find_combined_index(unsigned long page_idx
, unsigned int order
)
418 return (page_idx
& ~(1 << order
));
422 * This function checks whether a page is free && is the buddy
423 * we can do coalesce a page and its buddy if
424 * (a) the buddy is not in a hole &&
425 * (b) the buddy is in the buddy system &&
426 * (c) a page and its buddy have the same order &&
427 * (d) a page and its buddy are in the same zone.
429 * For recording whether a page is in the buddy system, we use PG_buddy.
430 * Setting, clearing, and testing PG_buddy is serialized by zone->lock.
432 * For recording page's order, we use page_private(page).
434 static inline int page_is_buddy(struct page
*page
, struct page
*buddy
,
437 if (!pfn_valid_within(page_to_pfn(buddy
)))
440 if (page_zone_id(page
) != page_zone_id(buddy
))
443 if (PageBuddy(buddy
) && page_order(buddy
) == order
) {
444 VM_BUG_ON(page_count(buddy
) != 0);
451 * Freeing function for a buddy system allocator.
453 * The concept of a buddy system is to maintain direct-mapped table
454 * (containing bit values) for memory blocks of various "orders".
455 * The bottom level table contains the map for the smallest allocatable
456 * units of memory (here, pages), and each level above it describes
457 * pairs of units from the levels below, hence, "buddies".
458 * At a high level, all that happens here is marking the table entry
459 * at the bottom level available, and propagating the changes upward
460 * as necessary, plus some accounting needed to play nicely with other
461 * parts of the VM system.
462 * At each level, we keep a list of pages, which are heads of continuous
463 * free pages of length of (1 << order) and marked with PG_buddy. Page's
464 * order is recorded in page_private(page) field.
465 * So when we are allocating or freeing one, we can derive the state of the
466 * other. That is, if we allocate a small block, and both were
467 * free, the remainder of the region must be split into blocks.
468 * If a block is freed, and its buddy is also free, then this
469 * triggers coalescing into a block of larger size.
474 static inline void __free_one_page(struct page
*page
,
475 struct zone
*zone
, unsigned int order
,
478 unsigned long page_idx
;
479 unsigned long combined_idx
;
482 if (unlikely(PageCompound(page
)))
483 if (unlikely(destroy_compound_page(page
, order
)))
486 VM_BUG_ON(migratetype
== -1);
488 page_idx
= page_to_pfn(page
) & ((1 << MAX_ORDER
) - 1);
490 VM_BUG_ON(page_idx
& ((1 << order
) - 1));
491 VM_BUG_ON(bad_range(zone
, page
));
493 while (order
< MAX_ORDER
-1) {
494 buddy
= __page_find_buddy(page
, page_idx
, order
);
495 if (!page_is_buddy(page
, buddy
, order
))
498 /* Our buddy is free, merge with it and move up one order. */
499 list_del(&buddy
->lru
);
500 zone
->free_area
[order
].nr_free
--;
501 rmv_page_order(buddy
);
502 combined_idx
= __find_combined_index(page_idx
, order
);
503 page
= page
+ (combined_idx
- page_idx
);
504 page_idx
= combined_idx
;
507 set_page_order(page
, order
);
510 * If this is not the largest possible page, check if the buddy
511 * of the next-highest order is free. If it is, it's possible
512 * that pages are being freed that will coalesce soon. In case,
513 * that is happening, add the free page to the tail of the list
514 * so it's less likely to be used soon and more likely to be merged
515 * as a higher order page
517 if ((order
< MAX_ORDER
-1) && pfn_valid_within(page_to_pfn(buddy
))) {
518 struct page
*higher_page
, *higher_buddy
;
519 combined_idx
= __find_combined_index(page_idx
, order
);
520 higher_page
= page
+ combined_idx
- page_idx
;
521 higher_buddy
= __page_find_buddy(higher_page
, combined_idx
, order
+ 1);
522 if (page_is_buddy(higher_page
, higher_buddy
, order
+ 1)) {
523 list_add_tail(&page
->lru
,
524 &zone
->free_area
[order
].free_list
[migratetype
]);
529 list_add(&page
->lru
, &zone
->free_area
[order
].free_list
[migratetype
]);
531 zone
->free_area
[order
].nr_free
++;
535 * free_page_mlock() -- clean up attempts to free and mlocked() page.
536 * Page should not be on lru, so no need to fix that up.
537 * free_pages_check() will verify...
539 static inline void free_page_mlock(struct page
*page
)
541 __dec_zone_page_state(page
, NR_MLOCK
);
542 __count_vm_event(UNEVICTABLE_MLOCKFREED
);
545 static inline int free_pages_check(struct page
*page
)
547 if (unlikely(page_mapcount(page
) |
548 (page
->mapping
!= NULL
) |
549 (atomic_read(&page
->_count
) != 0) |
550 (page
->flags
& PAGE_FLAGS_CHECK_AT_FREE
))) {
554 if (page
->flags
& PAGE_FLAGS_CHECK_AT_PREP
)
555 page
->flags
&= ~PAGE_FLAGS_CHECK_AT_PREP
;
560 * Frees a number of pages from the PCP lists
561 * Assumes all pages on list are in same zone, and of same order.
562 * count is the number of pages to free.
564 * If the zone was previously in an "all pages pinned" state then look to
565 * see if this freeing clears that state.
567 * And clear the zone's pages_scanned counter, to hold off the "all pages are
568 * pinned" detection logic.
570 static void free_pcppages_bulk(struct zone
*zone
, int count
,
571 struct per_cpu_pages
*pcp
)
576 spin_lock(&zone
->lock
);
577 zone
->all_unreclaimable
= 0;
578 zone
->pages_scanned
= 0;
580 __mod_zone_page_state(zone
, NR_FREE_PAGES
, count
);
583 struct list_head
*list
;
586 * Remove pages from lists in a round-robin fashion. A
587 * batch_free count is maintained that is incremented when an
588 * empty list is encountered. This is so more pages are freed
589 * off fuller lists instead of spinning excessively around empty
594 if (++migratetype
== MIGRATE_PCPTYPES
)
596 list
= &pcp
->lists
[migratetype
];
597 } while (list_empty(list
));
600 page
= list_entry(list
->prev
, struct page
, lru
);
601 /* must delete as __free_one_page list manipulates */
602 list_del(&page
->lru
);
603 /* MIGRATE_MOVABLE list may include MIGRATE_RESERVEs */
604 __free_one_page(page
, zone
, 0, page_private(page
));
605 trace_mm_page_pcpu_drain(page
, 0, page_private(page
));
606 } while (--count
&& --batch_free
&& !list_empty(list
));
608 spin_unlock(&zone
->lock
);
611 static void free_one_page(struct zone
*zone
, struct page
*page
, int order
,
614 spin_lock(&zone
->lock
);
615 zone
->all_unreclaimable
= 0;
616 zone
->pages_scanned
= 0;
618 __mod_zone_page_state(zone
, NR_FREE_PAGES
, 1 << order
);
619 __free_one_page(page
, zone
, order
, migratetype
);
620 spin_unlock(&zone
->lock
);
623 static bool free_pages_prepare(struct page
*page
, unsigned int order
)
628 trace_mm_page_free_direct(page
, order
);
629 kmemcheck_free_shadow(page
, order
);
631 for (i
= 0; i
< (1 << order
); i
++) {
632 struct page
*pg
= page
+ i
;
636 bad
+= free_pages_check(pg
);
641 if (!PageHighMem(page
)) {
642 debug_check_no_locks_freed(page_address(page
),PAGE_SIZE
<<order
);
643 debug_check_no_obj_freed(page_address(page
),
646 arch_free_page(page
, order
);
647 kernel_map_pages(page
, 1 << order
, 0);
652 static void __free_pages_ok(struct page
*page
, unsigned int order
)
655 int wasMlocked
= __TestClearPageMlocked(page
);
657 if (!free_pages_prepare(page
, order
))
660 local_irq_save(flags
);
661 if (unlikely(wasMlocked
))
662 free_page_mlock(page
);
663 __count_vm_events(PGFREE
, 1 << order
);
664 free_one_page(page_zone(page
), page
, order
,
665 get_pageblock_migratetype(page
));
666 local_irq_restore(flags
);
670 * permit the bootmem allocator to evade page validation on high-order frees
672 void __meminit
__free_pages_bootmem(struct page
*page
, unsigned int order
)
675 __ClearPageReserved(page
);
676 set_page_count(page
, 0);
677 set_page_refcounted(page
);
683 for (loop
= 0; loop
< BITS_PER_LONG
; loop
++) {
684 struct page
*p
= &page
[loop
];
686 if (loop
+ 1 < BITS_PER_LONG
)
688 __ClearPageReserved(p
);
689 set_page_count(p
, 0);
692 set_page_refcounted(page
);
693 __free_pages(page
, order
);
699 * The order of subdivision here is critical for the IO subsystem.
700 * Please do not alter this order without good reasons and regression
701 * testing. Specifically, as large blocks of memory are subdivided,
702 * the order in which smaller blocks are delivered depends on the order
703 * they're subdivided in this function. This is the primary factor
704 * influencing the order in which pages are delivered to the IO
705 * subsystem according to empirical testing, and this is also justified
706 * by considering the behavior of a buddy system containing a single
707 * large block of memory acted on by a series of small allocations.
708 * This behavior is a critical factor in sglist merging's success.
712 static inline void expand(struct zone
*zone
, struct page
*page
,
713 int low
, int high
, struct free_area
*area
,
716 unsigned long size
= 1 << high
;
722 VM_BUG_ON(bad_range(zone
, &page
[size
]));
723 list_add(&page
[size
].lru
, &area
->free_list
[migratetype
]);
725 set_page_order(&page
[size
], high
);
730 * This page is about to be returned from the page allocator
732 static inline int check_new_page(struct page
*page
)
734 if (unlikely(page_mapcount(page
) |
735 (page
->mapping
!= NULL
) |
736 (atomic_read(&page
->_count
) != 0) |
737 (page
->flags
& PAGE_FLAGS_CHECK_AT_PREP
))) {
744 static int prep_new_page(struct page
*page
, int order
, gfp_t gfp_flags
)
748 for (i
= 0; i
< (1 << order
); i
++) {
749 struct page
*p
= page
+ i
;
750 if (unlikely(check_new_page(p
)))
754 set_page_private(page
, 0);
755 set_page_refcounted(page
);
757 arch_alloc_page(page
, order
);
758 kernel_map_pages(page
, 1 << order
, 1);
760 if (gfp_flags
& __GFP_ZERO
)
761 prep_zero_page(page
, order
, gfp_flags
);
763 if (order
&& (gfp_flags
& __GFP_COMP
))
764 prep_compound_page(page
, order
);
770 * Go through the free lists for the given migratetype and remove
771 * the smallest available page from the freelists
774 struct page
*__rmqueue_smallest(struct zone
*zone
, unsigned int order
,
777 unsigned int current_order
;
778 struct free_area
* area
;
781 /* Find a page of the appropriate size in the preferred list */
782 for (current_order
= order
; current_order
< MAX_ORDER
; ++current_order
) {
783 area
= &(zone
->free_area
[current_order
]);
784 if (list_empty(&area
->free_list
[migratetype
]))
787 page
= list_entry(area
->free_list
[migratetype
].next
,
789 list_del(&page
->lru
);
790 rmv_page_order(page
);
792 expand(zone
, page
, order
, current_order
, area
, migratetype
);
801 * This array describes the order lists are fallen back to when
802 * the free lists for the desirable migrate type are depleted
804 static int fallbacks
[MIGRATE_TYPES
][MIGRATE_TYPES
-1] = {
805 [MIGRATE_UNMOVABLE
] = { MIGRATE_RECLAIMABLE
, MIGRATE_MOVABLE
, MIGRATE_RESERVE
},
806 [MIGRATE_RECLAIMABLE
] = { MIGRATE_UNMOVABLE
, MIGRATE_MOVABLE
, MIGRATE_RESERVE
},
807 [MIGRATE_MOVABLE
] = { MIGRATE_RECLAIMABLE
, MIGRATE_UNMOVABLE
, MIGRATE_RESERVE
},
808 [MIGRATE_RESERVE
] = { MIGRATE_RESERVE
, MIGRATE_RESERVE
, MIGRATE_RESERVE
}, /* Never used */
812 * Move the free pages in a range to the free lists of the requested type.
813 * Note that start_page and end_pages are not aligned on a pageblock
814 * boundary. If alignment is required, use move_freepages_block()
816 static int move_freepages(struct zone
*zone
,
817 struct page
*start_page
, struct page
*end_page
,
824 #ifndef CONFIG_HOLES_IN_ZONE
826 * page_zone is not safe to call in this context when
827 * CONFIG_HOLES_IN_ZONE is set. This bug check is probably redundant
828 * anyway as we check zone boundaries in move_freepages_block().
829 * Remove at a later date when no bug reports exist related to
830 * grouping pages by mobility
832 BUG_ON(page_zone(start_page
) != page_zone(end_page
));
835 for (page
= start_page
; page
<= end_page
;) {
836 /* Make sure we are not inadvertently changing nodes */
837 VM_BUG_ON(page_to_nid(page
) != zone_to_nid(zone
));
839 if (!pfn_valid_within(page_to_pfn(page
))) {
844 if (!PageBuddy(page
)) {
849 order
= page_order(page
);
850 list_del(&page
->lru
);
852 &zone
->free_area
[order
].free_list
[migratetype
]);
854 pages_moved
+= 1 << order
;
860 static int move_freepages_block(struct zone
*zone
, struct page
*page
,
863 unsigned long start_pfn
, end_pfn
;
864 struct page
*start_page
, *end_page
;
866 start_pfn
= page_to_pfn(page
);
867 start_pfn
= start_pfn
& ~(pageblock_nr_pages
-1);
868 start_page
= pfn_to_page(start_pfn
);
869 end_page
= start_page
+ pageblock_nr_pages
- 1;
870 end_pfn
= start_pfn
+ pageblock_nr_pages
- 1;
872 /* Do not cross zone boundaries */
873 if (start_pfn
< zone
->zone_start_pfn
)
875 if (end_pfn
>= zone
->zone_start_pfn
+ zone
->spanned_pages
)
878 return move_freepages(zone
, start_page
, end_page
, migratetype
);
881 static void change_pageblock_range(struct page
*pageblock_page
,
882 int start_order
, int migratetype
)
884 int nr_pageblocks
= 1 << (start_order
- pageblock_order
);
886 while (nr_pageblocks
--) {
887 set_pageblock_migratetype(pageblock_page
, migratetype
);
888 pageblock_page
+= pageblock_nr_pages
;
892 /* Remove an element from the buddy allocator from the fallback list */
893 static inline struct page
*
894 __rmqueue_fallback(struct zone
*zone
, int order
, int start_migratetype
)
896 struct free_area
* area
;
901 /* Find the largest possible block of pages in the other list */
902 for (current_order
= MAX_ORDER
-1; current_order
>= order
;
904 for (i
= 0; i
< MIGRATE_TYPES
- 1; i
++) {
905 migratetype
= fallbacks
[start_migratetype
][i
];
907 /* MIGRATE_RESERVE handled later if necessary */
908 if (migratetype
== MIGRATE_RESERVE
)
911 area
= &(zone
->free_area
[current_order
]);
912 if (list_empty(&area
->free_list
[migratetype
]))
915 page
= list_entry(area
->free_list
[migratetype
].next
,
920 * If breaking a large block of pages, move all free
921 * pages to the preferred allocation list. If falling
922 * back for a reclaimable kernel allocation, be more
923 * agressive about taking ownership of free pages
925 if (unlikely(current_order
>= (pageblock_order
>> 1)) ||
926 start_migratetype
== MIGRATE_RECLAIMABLE
||
927 page_group_by_mobility_disabled
) {
929 pages
= move_freepages_block(zone
, page
,
932 /* Claim the whole block if over half of it is free */
933 if (pages
>= (1 << (pageblock_order
-1)) ||
934 page_group_by_mobility_disabled
)
935 set_pageblock_migratetype(page
,
938 migratetype
= start_migratetype
;
941 /* Remove the page from the freelists */
942 list_del(&page
->lru
);
943 rmv_page_order(page
);
945 /* Take ownership for orders >= pageblock_order */
946 if (current_order
>= pageblock_order
)
947 change_pageblock_range(page
, current_order
,
950 expand(zone
, page
, order
, current_order
, area
, migratetype
);
952 trace_mm_page_alloc_extfrag(page
, order
, current_order
,
953 start_migratetype
, migratetype
);
963 * Do the hard work of removing an element from the buddy allocator.
964 * Call me with the zone->lock already held.
966 static struct page
*__rmqueue(struct zone
*zone
, unsigned int order
,
972 page
= __rmqueue_smallest(zone
, order
, migratetype
);
974 if (unlikely(!page
) && migratetype
!= MIGRATE_RESERVE
) {
975 page
= __rmqueue_fallback(zone
, order
, migratetype
);
978 * Use MIGRATE_RESERVE rather than fail an allocation. goto
979 * is used because __rmqueue_smallest is an inline function
980 * and we want just one call site
983 migratetype
= MIGRATE_RESERVE
;
988 trace_mm_page_alloc_zone_locked(page
, order
, migratetype
);
993 * Obtain a specified number of elements from the buddy allocator, all under
994 * a single hold of the lock, for efficiency. Add them to the supplied list.
995 * Returns the number of new pages which were placed at *list.
997 static int rmqueue_bulk(struct zone
*zone
, unsigned int order
,
998 unsigned long count
, struct list_head
*list
,
999 int migratetype
, int cold
)
1003 spin_lock(&zone
->lock
);
1004 for (i
= 0; i
< count
; ++i
) {
1005 struct page
*page
= __rmqueue(zone
, order
, migratetype
);
1006 if (unlikely(page
== NULL
))
1010 * Split buddy pages returned by expand() are received here
1011 * in physical page order. The page is added to the callers and
1012 * list and the list head then moves forward. From the callers
1013 * perspective, the linked list is ordered by page number in
1014 * some conditions. This is useful for IO devices that can
1015 * merge IO requests if the physical pages are ordered
1018 if (likely(cold
== 0))
1019 list_add(&page
->lru
, list
);
1021 list_add_tail(&page
->lru
, list
);
1022 set_page_private(page
, migratetype
);
1025 __mod_zone_page_state(zone
, NR_FREE_PAGES
, -(i
<< order
));
1026 spin_unlock(&zone
->lock
);
1032 * Called from the vmstat counter updater to drain pagesets of this
1033 * currently executing processor on remote nodes after they have
1036 * Note that this function must be called with the thread pinned to
1037 * a single processor.
1039 void drain_zone_pages(struct zone
*zone
, struct per_cpu_pages
*pcp
)
1041 unsigned long flags
;
1044 local_irq_save(flags
);
1045 if (pcp
->count
>= pcp
->batch
)
1046 to_drain
= pcp
->batch
;
1048 to_drain
= pcp
->count
;
1049 free_pcppages_bulk(zone
, to_drain
, pcp
);
1050 pcp
->count
-= to_drain
;
1051 local_irq_restore(flags
);
1056 * Drain pages of the indicated processor.
1058 * The processor must either be the current processor and the
1059 * thread pinned to the current processor or a processor that
1062 static void drain_pages(unsigned int cpu
)
1064 unsigned long flags
;
1067 for_each_populated_zone(zone
) {
1068 struct per_cpu_pageset
*pset
;
1069 struct per_cpu_pages
*pcp
;
1071 local_irq_save(flags
);
1072 pset
= per_cpu_ptr(zone
->pageset
, cpu
);
1075 free_pcppages_bulk(zone
, pcp
->count
, pcp
);
1077 local_irq_restore(flags
);
1082 * Spill all of this CPU's per-cpu pages back into the buddy allocator.
1084 void drain_local_pages(void *arg
)
1086 drain_pages(smp_processor_id());
1090 * Spill all the per-cpu pages from all CPUs back into the buddy allocator
1092 void drain_all_pages(void)
1094 on_each_cpu(drain_local_pages
, NULL
, 1);
1097 #ifdef CONFIG_HIBERNATION
1099 void mark_free_pages(struct zone
*zone
)
1101 unsigned long pfn
, max_zone_pfn
;
1102 unsigned long flags
;
1104 struct list_head
*curr
;
1106 if (!zone
->spanned_pages
)
1109 spin_lock_irqsave(&zone
->lock
, flags
);
1111 max_zone_pfn
= zone
->zone_start_pfn
+ zone
->spanned_pages
;
1112 for (pfn
= zone
->zone_start_pfn
; pfn
< max_zone_pfn
; pfn
++)
1113 if (pfn_valid(pfn
)) {
1114 struct page
*page
= pfn_to_page(pfn
);
1116 if (!swsusp_page_is_forbidden(page
))
1117 swsusp_unset_page_free(page
);
1120 for_each_migratetype_order(order
, t
) {
1121 list_for_each(curr
, &zone
->free_area
[order
].free_list
[t
]) {
1124 pfn
= page_to_pfn(list_entry(curr
, struct page
, lru
));
1125 for (i
= 0; i
< (1UL << order
); i
++)
1126 swsusp_set_page_free(pfn_to_page(pfn
+ i
));
1129 spin_unlock_irqrestore(&zone
->lock
, flags
);
1131 #endif /* CONFIG_PM */
1134 * Free a 0-order page
1135 * cold == 1 ? free a cold page : free a hot page
1137 void free_hot_cold_page(struct page
*page
, int cold
)
1139 struct zone
*zone
= page_zone(page
);
1140 struct per_cpu_pages
*pcp
;
1141 unsigned long flags
;
1143 int wasMlocked
= __TestClearPageMlocked(page
);
1145 if (!free_pages_prepare(page
, 0))
1148 migratetype
= get_pageblock_migratetype(page
);
1149 set_page_private(page
, migratetype
);
1150 local_irq_save(flags
);
1151 if (unlikely(wasMlocked
))
1152 free_page_mlock(page
);
1153 __count_vm_event(PGFREE
);
1156 * We only track unmovable, reclaimable and movable on pcp lists.
1157 * Free ISOLATE pages back to the allocator because they are being
1158 * offlined but treat RESERVE as movable pages so we can get those
1159 * areas back if necessary. Otherwise, we may have to free
1160 * excessively into the page allocator
1162 if (migratetype
>= MIGRATE_PCPTYPES
) {
1163 if (unlikely(migratetype
== MIGRATE_ISOLATE
)) {
1164 free_one_page(zone
, page
, 0, migratetype
);
1167 migratetype
= MIGRATE_MOVABLE
;
1170 pcp
= &this_cpu_ptr(zone
->pageset
)->pcp
;
1172 list_add_tail(&page
->lru
, &pcp
->lists
[migratetype
]);
1174 list_add(&page
->lru
, &pcp
->lists
[migratetype
]);
1176 if (pcp
->count
>= pcp
->high
) {
1177 free_pcppages_bulk(zone
, pcp
->batch
, pcp
);
1178 pcp
->count
-= pcp
->batch
;
1182 local_irq_restore(flags
);
1186 * split_page takes a non-compound higher-order page, and splits it into
1187 * n (1<<order) sub-pages: page[0..n]
1188 * Each sub-page must be freed individually.
1190 * Note: this is probably too low level an operation for use in drivers.
1191 * Please consult with lkml before using this in your driver.
1193 void split_page(struct page
*page
, unsigned int order
)
1197 VM_BUG_ON(PageCompound(page
));
1198 VM_BUG_ON(!page_count(page
));
1200 #ifdef CONFIG_KMEMCHECK
1202 * Split shadow pages too, because free(page[0]) would
1203 * otherwise free the whole shadow.
1205 if (kmemcheck_page_is_tracked(page
))
1206 split_page(virt_to_page(page
[0].shadow
), order
);
1209 for (i
= 1; i
< (1 << order
); i
++)
1210 set_page_refcounted(page
+ i
);
1214 * Similar to split_page except the page is already free. As this is only
1215 * being used for migration, the migratetype of the block also changes.
1216 * As this is called with interrupts disabled, the caller is responsible
1217 * for calling arch_alloc_page() and kernel_map_page() after interrupts
1220 * Note: this is probably too low level an operation for use in drivers.
1221 * Please consult with lkml before using this in your driver.
1223 int split_free_page(struct page
*page
)
1226 unsigned long watermark
;
1229 BUG_ON(!PageBuddy(page
));
1231 zone
= page_zone(page
);
1232 order
= page_order(page
);
1234 /* Obey watermarks as if the page was being allocated */
1235 watermark
= low_wmark_pages(zone
) + (1 << order
);
1236 if (!zone_watermark_ok(zone
, 0, watermark
, 0, 0))
1239 /* Remove page from free list */
1240 list_del(&page
->lru
);
1241 zone
->free_area
[order
].nr_free
--;
1242 rmv_page_order(page
);
1243 __mod_zone_page_state(zone
, NR_FREE_PAGES
, -(1UL << order
));
1245 /* Split into individual pages */
1246 set_page_refcounted(page
);
1247 split_page(page
, order
);
1249 if (order
>= pageblock_order
- 1) {
1250 struct page
*endpage
= page
+ (1 << order
) - 1;
1251 for (; page
< endpage
; page
+= pageblock_nr_pages
)
1252 set_pageblock_migratetype(page
, MIGRATE_MOVABLE
);
1259 * Really, prep_compound_page() should be called from __rmqueue_bulk(). But
1260 * we cheat by calling it from here, in the order > 0 path. Saves a branch
1264 struct page
*buffered_rmqueue(struct zone
*preferred_zone
,
1265 struct zone
*zone
, int order
, gfp_t gfp_flags
,
1268 unsigned long flags
;
1270 int cold
= !!(gfp_flags
& __GFP_COLD
);
1273 if (likely(order
== 0)) {
1274 struct per_cpu_pages
*pcp
;
1275 struct list_head
*list
;
1277 local_irq_save(flags
);
1278 pcp
= &this_cpu_ptr(zone
->pageset
)->pcp
;
1279 list
= &pcp
->lists
[migratetype
];
1280 if (list_empty(list
)) {
1281 pcp
->count
+= rmqueue_bulk(zone
, 0,
1284 if (unlikely(list_empty(list
)))
1289 page
= list_entry(list
->prev
, struct page
, lru
);
1291 page
= list_entry(list
->next
, struct page
, lru
);
1293 list_del(&page
->lru
);
1296 if (unlikely(gfp_flags
& __GFP_NOFAIL
)) {
1298 * __GFP_NOFAIL is not to be used in new code.
1300 * All __GFP_NOFAIL callers should be fixed so that they
1301 * properly detect and handle allocation failures.
1303 * We most definitely don't want callers attempting to
1304 * allocate greater than order-1 page units with
1307 WARN_ON_ONCE(order
> 1);
1309 spin_lock_irqsave(&zone
->lock
, flags
);
1310 page
= __rmqueue(zone
, order
, migratetype
);
1311 spin_unlock(&zone
->lock
);
1314 __mod_zone_page_state(zone
, NR_FREE_PAGES
, -(1 << order
));
1317 __count_zone_vm_events(PGALLOC
, zone
, 1 << order
);
1318 zone_statistics(preferred_zone
, zone
);
1319 local_irq_restore(flags
);
1321 VM_BUG_ON(bad_range(zone
, page
));
1322 if (prep_new_page(page
, order
, gfp_flags
))
1327 local_irq_restore(flags
);
1331 /* The ALLOC_WMARK bits are used as an index to zone->watermark */
1332 #define ALLOC_WMARK_MIN WMARK_MIN
1333 #define ALLOC_WMARK_LOW WMARK_LOW
1334 #define ALLOC_WMARK_HIGH WMARK_HIGH
1335 #define ALLOC_NO_WATERMARKS 0x04 /* don't check watermarks at all */
1337 /* Mask to get the watermark bits */
1338 #define ALLOC_WMARK_MASK (ALLOC_NO_WATERMARKS-1)
1340 #define ALLOC_HARDER 0x10 /* try to alloc harder */
1341 #define ALLOC_HIGH 0x20 /* __GFP_HIGH set */
1342 #define ALLOC_CPUSET 0x40 /* check for correct cpuset */
1344 #ifdef CONFIG_FAIL_PAGE_ALLOC
1346 static struct fail_page_alloc_attr
{
1347 struct fault_attr attr
;
1349 u32 ignore_gfp_highmem
;
1350 u32 ignore_gfp_wait
;
1353 #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
1355 struct dentry
*ignore_gfp_highmem_file
;
1356 struct dentry
*ignore_gfp_wait_file
;
1357 struct dentry
*min_order_file
;
1359 #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
1361 } fail_page_alloc
= {
1362 .attr
= FAULT_ATTR_INITIALIZER
,
1363 .ignore_gfp_wait
= 1,
1364 .ignore_gfp_highmem
= 1,
1368 static int __init
setup_fail_page_alloc(char *str
)
1370 return setup_fault_attr(&fail_page_alloc
.attr
, str
);
1372 __setup("fail_page_alloc=", setup_fail_page_alloc
);
1374 static int should_fail_alloc_page(gfp_t gfp_mask
, unsigned int order
)
1376 if (order
< fail_page_alloc
.min_order
)
1378 if (gfp_mask
& __GFP_NOFAIL
)
1380 if (fail_page_alloc
.ignore_gfp_highmem
&& (gfp_mask
& __GFP_HIGHMEM
))
1382 if (fail_page_alloc
.ignore_gfp_wait
&& (gfp_mask
& __GFP_WAIT
))
1385 return should_fail(&fail_page_alloc
.attr
, 1 << order
);
1388 #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
1390 static int __init
fail_page_alloc_debugfs(void)
1392 mode_t mode
= S_IFREG
| S_IRUSR
| S_IWUSR
;
1396 err
= init_fault_attr_dentries(&fail_page_alloc
.attr
,
1400 dir
= fail_page_alloc
.attr
.dentries
.dir
;
1402 fail_page_alloc
.ignore_gfp_wait_file
=
1403 debugfs_create_bool("ignore-gfp-wait", mode
, dir
,
1404 &fail_page_alloc
.ignore_gfp_wait
);
1406 fail_page_alloc
.ignore_gfp_highmem_file
=
1407 debugfs_create_bool("ignore-gfp-highmem", mode
, dir
,
1408 &fail_page_alloc
.ignore_gfp_highmem
);
1409 fail_page_alloc
.min_order_file
=
1410 debugfs_create_u32("min-order", mode
, dir
,
1411 &fail_page_alloc
.min_order
);
1413 if (!fail_page_alloc
.ignore_gfp_wait_file
||
1414 !fail_page_alloc
.ignore_gfp_highmem_file
||
1415 !fail_page_alloc
.min_order_file
) {
1417 debugfs_remove(fail_page_alloc
.ignore_gfp_wait_file
);
1418 debugfs_remove(fail_page_alloc
.ignore_gfp_highmem_file
);
1419 debugfs_remove(fail_page_alloc
.min_order_file
);
1420 cleanup_fault_attr_dentries(&fail_page_alloc
.attr
);
1426 late_initcall(fail_page_alloc_debugfs
);
1428 #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
1430 #else /* CONFIG_FAIL_PAGE_ALLOC */
1432 static inline int should_fail_alloc_page(gfp_t gfp_mask
, unsigned int order
)
1437 #endif /* CONFIG_FAIL_PAGE_ALLOC */
1440 * Return 1 if free pages are above 'mark'. This takes into account the order
1441 * of the allocation.
1443 int zone_watermark_ok(struct zone
*z
, int order
, unsigned long mark
,
1444 int classzone_idx
, int alloc_flags
)
1446 /* free_pages my go negative - that's OK */
1448 long free_pages
= zone_page_state(z
, NR_FREE_PAGES
) - (1 << order
) + 1;
1451 if (alloc_flags
& ALLOC_HIGH
)
1453 if (alloc_flags
& ALLOC_HARDER
)
1456 if (free_pages
<= min
+ z
->lowmem_reserve
[classzone_idx
])
1458 for (o
= 0; o
< order
; o
++) {
1459 /* At the next order, this order's pages become unavailable */
1460 free_pages
-= z
->free_area
[o
].nr_free
<< o
;
1462 /* Require fewer higher order pages to be free */
1465 if (free_pages
<= min
)
1473 * zlc_setup - Setup for "zonelist cache". Uses cached zone data to
1474 * skip over zones that are not allowed by the cpuset, or that have
1475 * been recently (in last second) found to be nearly full. See further
1476 * comments in mmzone.h. Reduces cache footprint of zonelist scans
1477 * that have to skip over a lot of full or unallowed zones.
1479 * If the zonelist cache is present in the passed in zonelist, then
1480 * returns a pointer to the allowed node mask (either the current
1481 * tasks mems_allowed, or node_states[N_HIGH_MEMORY].)
1483 * If the zonelist cache is not available for this zonelist, does
1484 * nothing and returns NULL.
1486 * If the fullzones BITMAP in the zonelist cache is stale (more than
1487 * a second since last zap'd) then we zap it out (clear its bits.)
1489 * We hold off even calling zlc_setup, until after we've checked the
1490 * first zone in the zonelist, on the theory that most allocations will
1491 * be satisfied from that first zone, so best to examine that zone as
1492 * quickly as we can.
1494 static nodemask_t
*zlc_setup(struct zonelist
*zonelist
, int alloc_flags
)
1496 struct zonelist_cache
*zlc
; /* cached zonelist speedup info */
1497 nodemask_t
*allowednodes
; /* zonelist_cache approximation */
1499 zlc
= zonelist
->zlcache_ptr
;
1503 if (time_after(jiffies
, zlc
->last_full_zap
+ HZ
)) {
1504 bitmap_zero(zlc
->fullzones
, MAX_ZONES_PER_ZONELIST
);
1505 zlc
->last_full_zap
= jiffies
;
1508 allowednodes
= !in_interrupt() && (alloc_flags
& ALLOC_CPUSET
) ?
1509 &cpuset_current_mems_allowed
:
1510 &node_states
[N_HIGH_MEMORY
];
1511 return allowednodes
;
1515 * Given 'z' scanning a zonelist, run a couple of quick checks to see
1516 * if it is worth looking at further for free memory:
1517 * 1) Check that the zone isn't thought to be full (doesn't have its
1518 * bit set in the zonelist_cache fullzones BITMAP).
1519 * 2) Check that the zones node (obtained from the zonelist_cache
1520 * z_to_n[] mapping) is allowed in the passed in allowednodes mask.
1521 * Return true (non-zero) if zone is worth looking at further, or
1522 * else return false (zero) if it is not.
1524 * This check -ignores- the distinction between various watermarks,
1525 * such as GFP_HIGH, GFP_ATOMIC, PF_MEMALLOC, ... If a zone is
1526 * found to be full for any variation of these watermarks, it will
1527 * be considered full for up to one second by all requests, unless
1528 * we are so low on memory on all allowed nodes that we are forced
1529 * into the second scan of the zonelist.
1531 * In the second scan we ignore this zonelist cache and exactly
1532 * apply the watermarks to all zones, even it is slower to do so.
1533 * We are low on memory in the second scan, and should leave no stone
1534 * unturned looking for a free page.
1536 static int zlc_zone_worth_trying(struct zonelist
*zonelist
, struct zoneref
*z
,
1537 nodemask_t
*allowednodes
)
1539 struct zonelist_cache
*zlc
; /* cached zonelist speedup info */
1540 int i
; /* index of *z in zonelist zones */
1541 int n
; /* node that zone *z is on */
1543 zlc
= zonelist
->zlcache_ptr
;
1547 i
= z
- zonelist
->_zonerefs
;
1550 /* This zone is worth trying if it is allowed but not full */
1551 return node_isset(n
, *allowednodes
) && !test_bit(i
, zlc
->fullzones
);
1555 * Given 'z' scanning a zonelist, set the corresponding bit in
1556 * zlc->fullzones, so that subsequent attempts to allocate a page
1557 * from that zone don't waste time re-examining it.
1559 static void zlc_mark_zone_full(struct zonelist
*zonelist
, struct zoneref
*z
)
1561 struct zonelist_cache
*zlc
; /* cached zonelist speedup info */
1562 int i
; /* index of *z in zonelist zones */
1564 zlc
= zonelist
->zlcache_ptr
;
1568 i
= z
- zonelist
->_zonerefs
;
1570 set_bit(i
, zlc
->fullzones
);
1573 #else /* CONFIG_NUMA */
1575 static nodemask_t
*zlc_setup(struct zonelist
*zonelist
, int alloc_flags
)
1580 static int zlc_zone_worth_trying(struct zonelist
*zonelist
, struct zoneref
*z
,
1581 nodemask_t
*allowednodes
)
1586 static void zlc_mark_zone_full(struct zonelist
*zonelist
, struct zoneref
*z
)
1589 #endif /* CONFIG_NUMA */
1592 * get_page_from_freelist goes through the zonelist trying to allocate
1595 static struct page
*
1596 get_page_from_freelist(gfp_t gfp_mask
, nodemask_t
*nodemask
, unsigned int order
,
1597 struct zonelist
*zonelist
, int high_zoneidx
, int alloc_flags
,
1598 struct zone
*preferred_zone
, int migratetype
)
1601 struct page
*page
= NULL
;
1604 nodemask_t
*allowednodes
= NULL
;/* zonelist_cache approximation */
1605 int zlc_active
= 0; /* set if using zonelist_cache */
1606 int did_zlc_setup
= 0; /* just call zlc_setup() one time */
1608 classzone_idx
= zone_idx(preferred_zone
);
1611 * Scan zonelist, looking for a zone with enough free.
1612 * See also cpuset_zone_allowed() comment in kernel/cpuset.c.
1614 for_each_zone_zonelist_nodemask(zone
, z
, zonelist
,
1615 high_zoneidx
, nodemask
) {
1616 if (NUMA_BUILD
&& zlc_active
&&
1617 !zlc_zone_worth_trying(zonelist
, z
, allowednodes
))
1619 if ((alloc_flags
& ALLOC_CPUSET
) &&
1620 !cpuset_zone_allowed_softwall(zone
, gfp_mask
))
1623 BUILD_BUG_ON(ALLOC_NO_WATERMARKS
< NR_WMARK
);
1624 if (!(alloc_flags
& ALLOC_NO_WATERMARKS
)) {
1628 mark
= zone
->watermark
[alloc_flags
& ALLOC_WMARK_MASK
];
1629 if (zone_watermark_ok(zone
, order
, mark
,
1630 classzone_idx
, alloc_flags
))
1633 if (zone_reclaim_mode
== 0)
1634 goto this_zone_full
;
1636 ret
= zone_reclaim(zone
, gfp_mask
, order
);
1638 case ZONE_RECLAIM_NOSCAN
:
1641 case ZONE_RECLAIM_FULL
:
1642 /* scanned but unreclaimable */
1643 goto this_zone_full
;
1645 /* did we reclaim enough */
1646 if (!zone_watermark_ok(zone
, order
, mark
,
1647 classzone_idx
, alloc_flags
))
1648 goto this_zone_full
;
1653 page
= buffered_rmqueue(preferred_zone
, zone
, order
,
1654 gfp_mask
, migratetype
);
1659 zlc_mark_zone_full(zonelist
, z
);
1661 if (NUMA_BUILD
&& !did_zlc_setup
&& nr_online_nodes
> 1) {
1663 * we do zlc_setup after the first zone is tried but only
1664 * if there are multiple nodes make it worthwhile
1666 allowednodes
= zlc_setup(zonelist
, alloc_flags
);
1672 if (unlikely(NUMA_BUILD
&& page
== NULL
&& zlc_active
)) {
1673 /* Disable zlc cache for second zonelist scan */
1681 should_alloc_retry(gfp_t gfp_mask
, unsigned int order
,
1682 unsigned long pages_reclaimed
)
1684 /* Do not loop if specifically requested */
1685 if (gfp_mask
& __GFP_NORETRY
)
1689 * In this implementation, order <= PAGE_ALLOC_COSTLY_ORDER
1690 * means __GFP_NOFAIL, but that may not be true in other
1693 if (order
<= PAGE_ALLOC_COSTLY_ORDER
)
1697 * For order > PAGE_ALLOC_COSTLY_ORDER, if __GFP_REPEAT is
1698 * specified, then we retry until we no longer reclaim any pages
1699 * (above), or we've reclaimed an order of pages at least as
1700 * large as the allocation's order. In both cases, if the
1701 * allocation still fails, we stop retrying.
1703 if (gfp_mask
& __GFP_REPEAT
&& pages_reclaimed
< (1 << order
))
1707 * Don't let big-order allocations loop unless the caller
1708 * explicitly requests that.
1710 if (gfp_mask
& __GFP_NOFAIL
)
1716 static inline struct page
*
1717 __alloc_pages_may_oom(gfp_t gfp_mask
, unsigned int order
,
1718 struct zonelist
*zonelist
, enum zone_type high_zoneidx
,
1719 nodemask_t
*nodemask
, struct zone
*preferred_zone
,
1724 /* Acquire the OOM killer lock for the zones in zonelist */
1725 if (!try_set_zone_oom(zonelist
, gfp_mask
)) {
1726 schedule_timeout_uninterruptible(1);
1731 * Go through the zonelist yet one more time, keep very high watermark
1732 * here, this is only to catch a parallel oom killing, we must fail if
1733 * we're still under heavy pressure.
1735 page
= get_page_from_freelist(gfp_mask
|__GFP_HARDWALL
, nodemask
,
1736 order
, zonelist
, high_zoneidx
,
1737 ALLOC_WMARK_HIGH
|ALLOC_CPUSET
,
1738 preferred_zone
, migratetype
);
1742 if (!(gfp_mask
& __GFP_NOFAIL
)) {
1743 /* The OOM killer will not help higher order allocs */
1744 if (order
> PAGE_ALLOC_COSTLY_ORDER
)
1747 * GFP_THISNODE contains __GFP_NORETRY and we never hit this.
1748 * Sanity check for bare calls of __GFP_THISNODE, not real OOM.
1749 * The caller should handle page allocation failure by itself if
1750 * it specifies __GFP_THISNODE.
1751 * Note: Hugepage uses it but will hit PAGE_ALLOC_COSTLY_ORDER.
1753 if (gfp_mask
& __GFP_THISNODE
)
1756 /* Exhausted what can be done so it's blamo time */
1757 out_of_memory(zonelist
, gfp_mask
, order
, nodemask
);
1760 clear_zonelist_oom(zonelist
, gfp_mask
);
1764 #ifdef CONFIG_COMPACTION
1765 /* Try memory compaction for high-order allocations before reclaim */
1766 static struct page
*
1767 __alloc_pages_direct_compact(gfp_t gfp_mask
, unsigned int order
,
1768 struct zonelist
*zonelist
, enum zone_type high_zoneidx
,
1769 nodemask_t
*nodemask
, int alloc_flags
, struct zone
*preferred_zone
,
1770 int migratetype
, unsigned long *did_some_progress
)
1774 if (!order
|| compaction_deferred(preferred_zone
))
1777 *did_some_progress
= try_to_compact_pages(zonelist
, order
, gfp_mask
,
1779 if (*did_some_progress
!= COMPACT_SKIPPED
) {
1781 /* Page migration frees to the PCP lists but we want merging */
1782 drain_pages(get_cpu());
1785 page
= get_page_from_freelist(gfp_mask
, nodemask
,
1786 order
, zonelist
, high_zoneidx
,
1787 alloc_flags
, preferred_zone
,
1790 preferred_zone
->compact_considered
= 0;
1791 preferred_zone
->compact_defer_shift
= 0;
1792 count_vm_event(COMPACTSUCCESS
);
1797 * It's bad if compaction run occurs and fails.
1798 * The most likely reason is that pages exist,
1799 * but not enough to satisfy watermarks.
1801 count_vm_event(COMPACTFAIL
);
1802 defer_compaction(preferred_zone
);
1810 static inline struct page
*
1811 __alloc_pages_direct_compact(gfp_t gfp_mask
, unsigned int order
,
1812 struct zonelist
*zonelist
, enum zone_type high_zoneidx
,
1813 nodemask_t
*nodemask
, int alloc_flags
, struct zone
*preferred_zone
,
1814 int migratetype
, unsigned long *did_some_progress
)
1818 #endif /* CONFIG_COMPACTION */
1820 /* The really slow allocator path where we enter direct reclaim */
1821 static inline struct page
*
1822 __alloc_pages_direct_reclaim(gfp_t gfp_mask
, unsigned int order
,
1823 struct zonelist
*zonelist
, enum zone_type high_zoneidx
,
1824 nodemask_t
*nodemask
, int alloc_flags
, struct zone
*preferred_zone
,
1825 int migratetype
, unsigned long *did_some_progress
)
1827 struct page
*page
= NULL
;
1828 struct reclaim_state reclaim_state
;
1829 struct task_struct
*p
= current
;
1833 /* We now go into synchronous reclaim */
1834 cpuset_memory_pressure_bump();
1835 p
->flags
|= PF_MEMALLOC
;
1836 lockdep_set_current_reclaim_state(gfp_mask
);
1837 reclaim_state
.reclaimed_slab
= 0;
1838 p
->reclaim_state
= &reclaim_state
;
1840 *did_some_progress
= try_to_free_pages(zonelist
, order
, gfp_mask
, nodemask
);
1842 p
->reclaim_state
= NULL
;
1843 lockdep_clear_current_reclaim_state();
1844 p
->flags
&= ~PF_MEMALLOC
;
1851 if (likely(*did_some_progress
))
1852 page
= get_page_from_freelist(gfp_mask
, nodemask
, order
,
1853 zonelist
, high_zoneidx
,
1854 alloc_flags
, preferred_zone
,
1860 * This is called in the allocator slow-path if the allocation request is of
1861 * sufficient urgency to ignore watermarks and take other desperate measures
1863 static inline struct page
*
1864 __alloc_pages_high_priority(gfp_t gfp_mask
, unsigned int order
,
1865 struct zonelist
*zonelist
, enum zone_type high_zoneidx
,
1866 nodemask_t
*nodemask
, struct zone
*preferred_zone
,
1872 page
= get_page_from_freelist(gfp_mask
, nodemask
, order
,
1873 zonelist
, high_zoneidx
, ALLOC_NO_WATERMARKS
,
1874 preferred_zone
, migratetype
);
1876 if (!page
&& gfp_mask
& __GFP_NOFAIL
)
1877 congestion_wait(BLK_RW_ASYNC
, HZ
/50);
1878 } while (!page
&& (gfp_mask
& __GFP_NOFAIL
));
1884 void wake_all_kswapd(unsigned int order
, struct zonelist
*zonelist
,
1885 enum zone_type high_zoneidx
)
1890 for_each_zone_zonelist(zone
, z
, zonelist
, high_zoneidx
)
1891 wakeup_kswapd(zone
, order
);
1895 gfp_to_alloc_flags(gfp_t gfp_mask
)
1897 struct task_struct
*p
= current
;
1898 int alloc_flags
= ALLOC_WMARK_MIN
| ALLOC_CPUSET
;
1899 const gfp_t wait
= gfp_mask
& __GFP_WAIT
;
1901 /* __GFP_HIGH is assumed to be the same as ALLOC_HIGH to save a branch. */
1902 BUILD_BUG_ON(__GFP_HIGH
!= ALLOC_HIGH
);
1905 * The caller may dip into page reserves a bit more if the caller
1906 * cannot run direct reclaim, or if the caller has realtime scheduling
1907 * policy or is asking for __GFP_HIGH memory. GFP_ATOMIC requests will
1908 * set both ALLOC_HARDER (!wait) and ALLOC_HIGH (__GFP_HIGH).
1910 alloc_flags
|= (gfp_mask
& __GFP_HIGH
);
1913 alloc_flags
|= ALLOC_HARDER
;
1915 * Ignore cpuset if GFP_ATOMIC (!wait) rather than fail alloc.
1916 * See also cpuset_zone_allowed() comment in kernel/cpuset.c.
1918 alloc_flags
&= ~ALLOC_CPUSET
;
1919 } else if (unlikely(rt_task(p
)) && !in_interrupt())
1920 alloc_flags
|= ALLOC_HARDER
;
1922 if (likely(!(gfp_mask
& __GFP_NOMEMALLOC
))) {
1923 if (!in_interrupt() &&
1924 ((p
->flags
& PF_MEMALLOC
) ||
1925 unlikely(test_thread_flag(TIF_MEMDIE
))))
1926 alloc_flags
|= ALLOC_NO_WATERMARKS
;
1932 static inline struct page
*
1933 __alloc_pages_slowpath(gfp_t gfp_mask
, unsigned int order
,
1934 struct zonelist
*zonelist
, enum zone_type high_zoneidx
,
1935 nodemask_t
*nodemask
, struct zone
*preferred_zone
,
1938 const gfp_t wait
= gfp_mask
& __GFP_WAIT
;
1939 struct page
*page
= NULL
;
1941 unsigned long pages_reclaimed
= 0;
1942 unsigned long did_some_progress
;
1943 struct task_struct
*p
= current
;
1946 * In the slowpath, we sanity check order to avoid ever trying to
1947 * reclaim >= MAX_ORDER areas which will never succeed. Callers may
1948 * be using allocators in order of preference for an area that is
1951 if (order
>= MAX_ORDER
) {
1952 WARN_ON_ONCE(!(gfp_mask
& __GFP_NOWARN
));
1957 * GFP_THISNODE (meaning __GFP_THISNODE, __GFP_NORETRY and
1958 * __GFP_NOWARN set) should not cause reclaim since the subsystem
1959 * (f.e. slab) using GFP_THISNODE may choose to trigger reclaim
1960 * using a larger set of nodes after it has established that the
1961 * allowed per node queues are empty and that nodes are
1964 if (NUMA_BUILD
&& (gfp_mask
& GFP_THISNODE
) == GFP_THISNODE
)
1968 wake_all_kswapd(order
, zonelist
, high_zoneidx
);
1971 * OK, we're below the kswapd watermark and have kicked background
1972 * reclaim. Now things get more complex, so set up alloc_flags according
1973 * to how we want to proceed.
1975 alloc_flags
= gfp_to_alloc_flags(gfp_mask
);
1977 /* This is the last chance, in general, before the goto nopage. */
1978 page
= get_page_from_freelist(gfp_mask
, nodemask
, order
, zonelist
,
1979 high_zoneidx
, alloc_flags
& ~ALLOC_NO_WATERMARKS
,
1980 preferred_zone
, migratetype
);
1985 /* Allocate without watermarks if the context allows */
1986 if (alloc_flags
& ALLOC_NO_WATERMARKS
) {
1987 page
= __alloc_pages_high_priority(gfp_mask
, order
,
1988 zonelist
, high_zoneidx
, nodemask
,
1989 preferred_zone
, migratetype
);
1994 /* Atomic allocations - we can't balance anything */
1998 /* Avoid recursion of direct reclaim */
1999 if (p
->flags
& PF_MEMALLOC
)
2002 /* Avoid allocations with no watermarks from looping endlessly */
2003 if (test_thread_flag(TIF_MEMDIE
) && !(gfp_mask
& __GFP_NOFAIL
))
2006 /* Try direct compaction */
2007 page
= __alloc_pages_direct_compact(gfp_mask
, order
,
2008 zonelist
, high_zoneidx
,
2010 alloc_flags
, preferred_zone
,
2011 migratetype
, &did_some_progress
);
2015 /* Try direct reclaim and then allocating */
2016 page
= __alloc_pages_direct_reclaim(gfp_mask
, order
,
2017 zonelist
, high_zoneidx
,
2019 alloc_flags
, preferred_zone
,
2020 migratetype
, &did_some_progress
);
2025 * If we failed to make any progress reclaiming, then we are
2026 * running out of options and have to consider going OOM
2028 if (!did_some_progress
) {
2029 if ((gfp_mask
& __GFP_FS
) && !(gfp_mask
& __GFP_NORETRY
)) {
2030 if (oom_killer_disabled
)
2032 page
= __alloc_pages_may_oom(gfp_mask
, order
,
2033 zonelist
, high_zoneidx
,
2034 nodemask
, preferred_zone
,
2040 * The OOM killer does not trigger for high-order
2041 * ~__GFP_NOFAIL allocations so if no progress is being
2042 * made, there are no other options and retrying is
2045 if (order
> PAGE_ALLOC_COSTLY_ORDER
&&
2046 !(gfp_mask
& __GFP_NOFAIL
))
2053 /* Check if we should retry the allocation */
2054 pages_reclaimed
+= did_some_progress
;
2055 if (should_alloc_retry(gfp_mask
, order
, pages_reclaimed
)) {
2056 /* Wait for some write requests to complete then retry */
2057 congestion_wait(BLK_RW_ASYNC
, HZ
/50);
2062 if (!(gfp_mask
& __GFP_NOWARN
) && printk_ratelimit()) {
2063 printk(KERN_WARNING
"%s: page allocation failure."
2064 " order:%d, mode:0x%x\n",
2065 p
->comm
, order
, gfp_mask
);
2071 if (kmemcheck_enabled
)
2072 kmemcheck_pagealloc_alloc(page
, order
, gfp_mask
);
2078 * This is the 'heart' of the zoned buddy allocator.
2081 __alloc_pages_nodemask(gfp_t gfp_mask
, unsigned int order
,
2082 struct zonelist
*zonelist
, nodemask_t
*nodemask
)
2084 enum zone_type high_zoneidx
= gfp_zone(gfp_mask
);
2085 struct zone
*preferred_zone
;
2087 int migratetype
= allocflags_to_migratetype(gfp_mask
);
2089 gfp_mask
&= gfp_allowed_mask
;
2091 lockdep_trace_alloc(gfp_mask
);
2093 might_sleep_if(gfp_mask
& __GFP_WAIT
);
2095 if (should_fail_alloc_page(gfp_mask
, order
))
2099 * Check the zones suitable for the gfp_mask contain at least one
2100 * valid zone. It's possible to have an empty zonelist as a result
2101 * of GFP_THISNODE and a memoryless node
2103 if (unlikely(!zonelist
->_zonerefs
->zone
))
2107 /* The preferred zone is used for statistics later */
2108 first_zones_zonelist(zonelist
, high_zoneidx
, nodemask
, &preferred_zone
);
2109 if (!preferred_zone
) {
2114 /* First allocation attempt */
2115 page
= get_page_from_freelist(gfp_mask
|__GFP_HARDWALL
, nodemask
, order
,
2116 zonelist
, high_zoneidx
, ALLOC_WMARK_LOW
|ALLOC_CPUSET
,
2117 preferred_zone
, migratetype
);
2118 if (unlikely(!page
))
2119 page
= __alloc_pages_slowpath(gfp_mask
, order
,
2120 zonelist
, high_zoneidx
, nodemask
,
2121 preferred_zone
, migratetype
);
2124 trace_mm_page_alloc(page
, order
, gfp_mask
, migratetype
);
2127 EXPORT_SYMBOL(__alloc_pages_nodemask
);
2130 * Common helper functions.
2132 unsigned long __get_free_pages(gfp_t gfp_mask
, unsigned int order
)
2137 * __get_free_pages() returns a 32-bit address, which cannot represent
2140 VM_BUG_ON((gfp_mask
& __GFP_HIGHMEM
) != 0);
2142 page
= alloc_pages(gfp_mask
, order
);
2145 return (unsigned long) page_address(page
);
2147 EXPORT_SYMBOL(__get_free_pages
);
2149 unsigned long get_zeroed_page(gfp_t gfp_mask
)
2151 return __get_free_pages(gfp_mask
| __GFP_ZERO
, 0);
2153 EXPORT_SYMBOL(get_zeroed_page
);
2155 void __pagevec_free(struct pagevec
*pvec
)
2157 int i
= pagevec_count(pvec
);
2160 trace_mm_pagevec_free(pvec
->pages
[i
], pvec
->cold
);
2161 free_hot_cold_page(pvec
->pages
[i
], pvec
->cold
);
2165 void __free_pages(struct page
*page
, unsigned int order
)
2167 if (put_page_testzero(page
)) {
2169 free_hot_cold_page(page
, 0);
2171 __free_pages_ok(page
, order
);
2175 EXPORT_SYMBOL(__free_pages
);
2177 void free_pages(unsigned long addr
, unsigned int order
)
2180 VM_BUG_ON(!virt_addr_valid((void *)addr
));
2181 __free_pages(virt_to_page((void *)addr
), order
);
2185 EXPORT_SYMBOL(free_pages
);
2188 * alloc_pages_exact - allocate an exact number physically-contiguous pages.
2189 * @size: the number of bytes to allocate
2190 * @gfp_mask: GFP flags for the allocation
2192 * This function is similar to alloc_pages(), except that it allocates the
2193 * minimum number of pages to satisfy the request. alloc_pages() can only
2194 * allocate memory in power-of-two pages.
2196 * This function is also limited by MAX_ORDER.
2198 * Memory allocated by this function must be released by free_pages_exact().
2200 void *alloc_pages_exact(size_t size
, gfp_t gfp_mask
)
2202 unsigned int order
= get_order(size
);
2205 addr
= __get_free_pages(gfp_mask
, order
);
2207 unsigned long alloc_end
= addr
+ (PAGE_SIZE
<< order
);
2208 unsigned long used
= addr
+ PAGE_ALIGN(size
);
2210 split_page(virt_to_page((void *)addr
), order
);
2211 while (used
< alloc_end
) {
2217 return (void *)addr
;
2219 EXPORT_SYMBOL(alloc_pages_exact
);
2222 * free_pages_exact - release memory allocated via alloc_pages_exact()
2223 * @virt: the value returned by alloc_pages_exact.
2224 * @size: size of allocation, same value as passed to alloc_pages_exact().
2226 * Release the memory allocated by a previous call to alloc_pages_exact.
2228 void free_pages_exact(void *virt
, size_t size
)
2230 unsigned long addr
= (unsigned long)virt
;
2231 unsigned long end
= addr
+ PAGE_ALIGN(size
);
2233 while (addr
< end
) {
2238 EXPORT_SYMBOL(free_pages_exact
);
2240 static unsigned int nr_free_zone_pages(int offset
)
2245 /* Just pick one node, since fallback list is circular */
2246 unsigned int sum
= 0;
2248 struct zonelist
*zonelist
= node_zonelist(numa_node_id(), GFP_KERNEL
);
2250 for_each_zone_zonelist(zone
, z
, zonelist
, offset
) {
2251 unsigned long size
= zone
->present_pages
;
2252 unsigned long high
= high_wmark_pages(zone
);
2261 * Amount of free RAM allocatable within ZONE_DMA and ZONE_NORMAL
2263 unsigned int nr_free_buffer_pages(void)
2265 return nr_free_zone_pages(gfp_zone(GFP_USER
));
2267 EXPORT_SYMBOL_GPL(nr_free_buffer_pages
);
2270 * Amount of free RAM allocatable within all zones
2272 unsigned int nr_free_pagecache_pages(void)
2274 return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE
));
2277 static inline void show_node(struct zone
*zone
)
2280 printk("Node %d ", zone_to_nid(zone
));
2283 void si_meminfo(struct sysinfo
*val
)
2285 val
->totalram
= totalram_pages
;
2287 val
->freeram
= global_page_state(NR_FREE_PAGES
);
2288 val
->bufferram
= nr_blockdev_pages();
2289 val
->totalhigh
= totalhigh_pages
;
2290 val
->freehigh
= nr_free_highpages();
2291 val
->mem_unit
= PAGE_SIZE
;
2294 EXPORT_SYMBOL(si_meminfo
);
2297 void si_meminfo_node(struct sysinfo
*val
, int nid
)
2299 pg_data_t
*pgdat
= NODE_DATA(nid
);
2301 val
->totalram
= pgdat
->node_present_pages
;
2302 val
->freeram
= node_page_state(nid
, NR_FREE_PAGES
);
2303 #ifdef CONFIG_HIGHMEM
2304 val
->totalhigh
= pgdat
->node_zones
[ZONE_HIGHMEM
].present_pages
;
2305 val
->freehigh
= zone_page_state(&pgdat
->node_zones
[ZONE_HIGHMEM
],
2311 val
->mem_unit
= PAGE_SIZE
;
2315 #define K(x) ((x) << (PAGE_SHIFT-10))
2318 * Show free area list (used inside shift_scroll-lock stuff)
2319 * We also calculate the percentage fragmentation. We do this by counting the
2320 * memory on each free list with the exception of the first item on the list.
2322 void show_free_areas(void)
2327 for_each_populated_zone(zone
) {
2329 printk("%s per-cpu:\n", zone
->name
);
2331 for_each_online_cpu(cpu
) {
2332 struct per_cpu_pageset
*pageset
;
2334 pageset
= per_cpu_ptr(zone
->pageset
, cpu
);
2336 printk("CPU %4d: hi:%5d, btch:%4d usd:%4d\n",
2337 cpu
, pageset
->pcp
.high
,
2338 pageset
->pcp
.batch
, pageset
->pcp
.count
);
2342 printk("active_anon:%lu inactive_anon:%lu isolated_anon:%lu\n"
2343 " active_file:%lu inactive_file:%lu isolated_file:%lu\n"
2345 " dirty:%lu writeback:%lu unstable:%lu\n"
2346 " free:%lu slab_reclaimable:%lu slab_unreclaimable:%lu\n"
2347 " mapped:%lu shmem:%lu pagetables:%lu bounce:%lu\n",
2348 global_page_state(NR_ACTIVE_ANON
),
2349 global_page_state(NR_INACTIVE_ANON
),
2350 global_page_state(NR_ISOLATED_ANON
),
2351 global_page_state(NR_ACTIVE_FILE
),
2352 global_page_state(NR_INACTIVE_FILE
),
2353 global_page_state(NR_ISOLATED_FILE
),
2354 global_page_state(NR_UNEVICTABLE
),
2355 global_page_state(NR_FILE_DIRTY
),
2356 global_page_state(NR_WRITEBACK
),
2357 global_page_state(NR_UNSTABLE_NFS
),
2358 global_page_state(NR_FREE_PAGES
),
2359 global_page_state(NR_SLAB_RECLAIMABLE
),
2360 global_page_state(NR_SLAB_UNRECLAIMABLE
),
2361 global_page_state(NR_FILE_MAPPED
),
2362 global_page_state(NR_SHMEM
),
2363 global_page_state(NR_PAGETABLE
),
2364 global_page_state(NR_BOUNCE
));
2366 for_each_populated_zone(zone
) {
2375 " active_anon:%lukB"
2376 " inactive_anon:%lukB"
2377 " active_file:%lukB"
2378 " inactive_file:%lukB"
2379 " unevictable:%lukB"
2380 " isolated(anon):%lukB"
2381 " isolated(file):%lukB"
2388 " slab_reclaimable:%lukB"
2389 " slab_unreclaimable:%lukB"
2390 " kernel_stack:%lukB"
2394 " writeback_tmp:%lukB"
2395 " pages_scanned:%lu"
2396 " all_unreclaimable? %s"
2399 K(zone_page_state(zone
, NR_FREE_PAGES
)),
2400 K(min_wmark_pages(zone
)),
2401 K(low_wmark_pages(zone
)),
2402 K(high_wmark_pages(zone
)),
2403 K(zone_page_state(zone
, NR_ACTIVE_ANON
)),
2404 K(zone_page_state(zone
, NR_INACTIVE_ANON
)),
2405 K(zone_page_state(zone
, NR_ACTIVE_FILE
)),
2406 K(zone_page_state(zone
, NR_INACTIVE_FILE
)),
2407 K(zone_page_state(zone
, NR_UNEVICTABLE
)),
2408 K(zone_page_state(zone
, NR_ISOLATED_ANON
)),
2409 K(zone_page_state(zone
, NR_ISOLATED_FILE
)),
2410 K(zone
->present_pages
),
2411 K(zone_page_state(zone
, NR_MLOCK
)),
2412 K(zone_page_state(zone
, NR_FILE_DIRTY
)),
2413 K(zone_page_state(zone
, NR_WRITEBACK
)),
2414 K(zone_page_state(zone
, NR_FILE_MAPPED
)),
2415 K(zone_page_state(zone
, NR_SHMEM
)),
2416 K(zone_page_state(zone
, NR_SLAB_RECLAIMABLE
)),
2417 K(zone_page_state(zone
, NR_SLAB_UNRECLAIMABLE
)),
2418 zone_page_state(zone
, NR_KERNEL_STACK
) *
2420 K(zone_page_state(zone
, NR_PAGETABLE
)),
2421 K(zone_page_state(zone
, NR_UNSTABLE_NFS
)),
2422 K(zone_page_state(zone
, NR_BOUNCE
)),
2423 K(zone_page_state(zone
, NR_WRITEBACK_TEMP
)),
2424 zone
->pages_scanned
,
2425 (zone
->all_unreclaimable
? "yes" : "no")
2427 printk("lowmem_reserve[]:");
2428 for (i
= 0; i
< MAX_NR_ZONES
; i
++)
2429 printk(" %lu", zone
->lowmem_reserve
[i
]);
2433 for_each_populated_zone(zone
) {
2434 unsigned long nr
[MAX_ORDER
], flags
, order
, total
= 0;
2437 printk("%s: ", zone
->name
);
2439 spin_lock_irqsave(&zone
->lock
, flags
);
2440 for (order
= 0; order
< MAX_ORDER
; order
++) {
2441 nr
[order
] = zone
->free_area
[order
].nr_free
;
2442 total
+= nr
[order
] << order
;
2444 spin_unlock_irqrestore(&zone
->lock
, flags
);
2445 for (order
= 0; order
< MAX_ORDER
; order
++)
2446 printk("%lu*%lukB ", nr
[order
], K(1UL) << order
);
2447 printk("= %lukB\n", K(total
));
2450 printk("%ld total pagecache pages\n", global_page_state(NR_FILE_PAGES
));
2452 show_swap_cache_info();
2455 static void zoneref_set_zone(struct zone
*zone
, struct zoneref
*zoneref
)
2457 zoneref
->zone
= zone
;
2458 zoneref
->zone_idx
= zone_idx(zone
);
2462 * Builds allocation fallback zone lists.
2464 * Add all populated zones of a node to the zonelist.
2466 static int build_zonelists_node(pg_data_t
*pgdat
, struct zonelist
*zonelist
,
2467 int nr_zones
, enum zone_type zone_type
)
2471 BUG_ON(zone_type
>= MAX_NR_ZONES
);
2476 zone
= pgdat
->node_zones
+ zone_type
;
2477 if (populated_zone(zone
)) {
2478 zoneref_set_zone(zone
,
2479 &zonelist
->_zonerefs
[nr_zones
++]);
2480 check_highest_zone(zone_type
);
2483 } while (zone_type
);
2490 * 0 = automatic detection of better ordering.
2491 * 1 = order by ([node] distance, -zonetype)
2492 * 2 = order by (-zonetype, [node] distance)
2494 * If not NUMA, ZONELIST_ORDER_ZONE and ZONELIST_ORDER_NODE will create
2495 * the same zonelist. So only NUMA can configure this param.
2497 #define ZONELIST_ORDER_DEFAULT 0
2498 #define ZONELIST_ORDER_NODE 1
2499 #define ZONELIST_ORDER_ZONE 2
2501 /* zonelist order in the kernel.
2502 * set_zonelist_order() will set this to NODE or ZONE.
2504 static int current_zonelist_order
= ZONELIST_ORDER_DEFAULT
;
2505 static char zonelist_order_name
[3][8] = {"Default", "Node", "Zone"};
2509 /* The value user specified ....changed by config */
2510 static int user_zonelist_order
= ZONELIST_ORDER_DEFAULT
;
2511 /* string for sysctl */
2512 #define NUMA_ZONELIST_ORDER_LEN 16
2513 char numa_zonelist_order
[16] = "default";
2516 * interface for configure zonelist ordering.
2517 * command line option "numa_zonelist_order"
2518 * = "[dD]efault - default, automatic configuration.
2519 * = "[nN]ode - order by node locality, then by zone within node
2520 * = "[zZ]one - order by zone, then by locality within zone
2523 static int __parse_numa_zonelist_order(char *s
)
2525 if (*s
== 'd' || *s
== 'D') {
2526 user_zonelist_order
= ZONELIST_ORDER_DEFAULT
;
2527 } else if (*s
== 'n' || *s
== 'N') {
2528 user_zonelist_order
= ZONELIST_ORDER_NODE
;
2529 } else if (*s
== 'z' || *s
== 'Z') {
2530 user_zonelist_order
= ZONELIST_ORDER_ZONE
;
2533 "Ignoring invalid numa_zonelist_order value: "
2540 static __init
int setup_numa_zonelist_order(char *s
)
2543 return __parse_numa_zonelist_order(s
);
2546 early_param("numa_zonelist_order", setup_numa_zonelist_order
);
2549 * sysctl handler for numa_zonelist_order
2551 int numa_zonelist_order_handler(ctl_table
*table
, int write
,
2552 void __user
*buffer
, size_t *length
,
2555 char saved_string
[NUMA_ZONELIST_ORDER_LEN
];
2557 static DEFINE_MUTEX(zl_order_mutex
);
2559 mutex_lock(&zl_order_mutex
);
2561 strcpy(saved_string
, (char*)table
->data
);
2562 ret
= proc_dostring(table
, write
, buffer
, length
, ppos
);
2566 int oldval
= user_zonelist_order
;
2567 if (__parse_numa_zonelist_order((char*)table
->data
)) {
2569 * bogus value. restore saved string
2571 strncpy((char*)table
->data
, saved_string
,
2572 NUMA_ZONELIST_ORDER_LEN
);
2573 user_zonelist_order
= oldval
;
2574 } else if (oldval
!= user_zonelist_order
) {
2575 mutex_lock(&zonelists_mutex
);
2576 build_all_zonelists(NULL
);
2577 mutex_unlock(&zonelists_mutex
);
2581 mutex_unlock(&zl_order_mutex
);
2586 #define MAX_NODE_LOAD (nr_online_nodes)
2587 static int node_load
[MAX_NUMNODES
];
2590 * find_next_best_node - find the next node that should appear in a given node's fallback list
2591 * @node: node whose fallback list we're appending
2592 * @used_node_mask: nodemask_t of already used nodes
2594 * We use a number of factors to determine which is the next node that should
2595 * appear on a given node's fallback list. The node should not have appeared
2596 * already in @node's fallback list, and it should be the next closest node
2597 * according to the distance array (which contains arbitrary distance values
2598 * from each node to each node in the system), and should also prefer nodes
2599 * with no CPUs, since presumably they'll have very little allocation pressure
2600 * on them otherwise.
2601 * It returns -1 if no node is found.
2603 static int find_next_best_node(int node
, nodemask_t
*used_node_mask
)
2606 int min_val
= INT_MAX
;
2608 const struct cpumask
*tmp
= cpumask_of_node(0);
2610 /* Use the local node if we haven't already */
2611 if (!node_isset(node
, *used_node_mask
)) {
2612 node_set(node
, *used_node_mask
);
2616 for_each_node_state(n
, N_HIGH_MEMORY
) {
2618 /* Don't want a node to appear more than once */
2619 if (node_isset(n
, *used_node_mask
))
2622 /* Use the distance array to find the distance */
2623 val
= node_distance(node
, n
);
2625 /* Penalize nodes under us ("prefer the next node") */
2628 /* Give preference to headless and unused nodes */
2629 tmp
= cpumask_of_node(n
);
2630 if (!cpumask_empty(tmp
))
2631 val
+= PENALTY_FOR_NODE_WITH_CPUS
;
2633 /* Slight preference for less loaded node */
2634 val
*= (MAX_NODE_LOAD
*MAX_NUMNODES
);
2635 val
+= node_load
[n
];
2637 if (val
< min_val
) {
2644 node_set(best_node
, *used_node_mask
);
2651 * Build zonelists ordered by node and zones within node.
2652 * This results in maximum locality--normal zone overflows into local
2653 * DMA zone, if any--but risks exhausting DMA zone.
2655 static void build_zonelists_in_node_order(pg_data_t
*pgdat
, int node
)
2658 struct zonelist
*zonelist
;
2660 zonelist
= &pgdat
->node_zonelists
[0];
2661 for (j
= 0; zonelist
->_zonerefs
[j
].zone
!= NULL
; j
++)
2663 j
= build_zonelists_node(NODE_DATA(node
), zonelist
, j
,
2665 zonelist
->_zonerefs
[j
].zone
= NULL
;
2666 zonelist
->_zonerefs
[j
].zone_idx
= 0;
2670 * Build gfp_thisnode zonelists
2672 static void build_thisnode_zonelists(pg_data_t
*pgdat
)
2675 struct zonelist
*zonelist
;
2677 zonelist
= &pgdat
->node_zonelists
[1];
2678 j
= build_zonelists_node(pgdat
, zonelist
, 0, MAX_NR_ZONES
- 1);
2679 zonelist
->_zonerefs
[j
].zone
= NULL
;
2680 zonelist
->_zonerefs
[j
].zone_idx
= 0;
2684 * Build zonelists ordered by zone and nodes within zones.
2685 * This results in conserving DMA zone[s] until all Normal memory is
2686 * exhausted, but results in overflowing to remote node while memory
2687 * may still exist in local DMA zone.
2689 static int node_order
[MAX_NUMNODES
];
2691 static void build_zonelists_in_zone_order(pg_data_t
*pgdat
, int nr_nodes
)
2694 int zone_type
; /* needs to be signed */
2696 struct zonelist
*zonelist
;
2698 zonelist
= &pgdat
->node_zonelists
[0];
2700 for (zone_type
= MAX_NR_ZONES
- 1; zone_type
>= 0; zone_type
--) {
2701 for (j
= 0; j
< nr_nodes
; j
++) {
2702 node
= node_order
[j
];
2703 z
= &NODE_DATA(node
)->node_zones
[zone_type
];
2704 if (populated_zone(z
)) {
2706 &zonelist
->_zonerefs
[pos
++]);
2707 check_highest_zone(zone_type
);
2711 zonelist
->_zonerefs
[pos
].zone
= NULL
;
2712 zonelist
->_zonerefs
[pos
].zone_idx
= 0;
2715 static int default_zonelist_order(void)
2718 unsigned long low_kmem_size
,total_size
;
2722 * ZONE_DMA and ZONE_DMA32 can be very small area in the system.
2723 * If they are really small and used heavily, the system can fall
2724 * into OOM very easily.
2725 * This function detect ZONE_DMA/DMA32 size and configures zone order.
2727 /* Is there ZONE_NORMAL ? (ex. ppc has only DMA zone..) */
2730 for_each_online_node(nid
) {
2731 for (zone_type
= 0; zone_type
< MAX_NR_ZONES
; zone_type
++) {
2732 z
= &NODE_DATA(nid
)->node_zones
[zone_type
];
2733 if (populated_zone(z
)) {
2734 if (zone_type
< ZONE_NORMAL
)
2735 low_kmem_size
+= z
->present_pages
;
2736 total_size
+= z
->present_pages
;
2737 } else if (zone_type
== ZONE_NORMAL
) {
2739 * If any node has only lowmem, then node order
2740 * is preferred to allow kernel allocations
2741 * locally; otherwise, they can easily infringe
2742 * on other nodes when there is an abundance of
2743 * lowmem available to allocate from.
2745 return ZONELIST_ORDER_NODE
;
2749 if (!low_kmem_size
|| /* there are no DMA area. */
2750 low_kmem_size
> total_size
/2) /* DMA/DMA32 is big. */
2751 return ZONELIST_ORDER_NODE
;
2753 * look into each node's config.
2754 * If there is a node whose DMA/DMA32 memory is very big area on
2755 * local memory, NODE_ORDER may be suitable.
2757 average_size
= total_size
/
2758 (nodes_weight(node_states
[N_HIGH_MEMORY
]) + 1);
2759 for_each_online_node(nid
) {
2762 for (zone_type
= 0; zone_type
< MAX_NR_ZONES
; zone_type
++) {
2763 z
= &NODE_DATA(nid
)->node_zones
[zone_type
];
2764 if (populated_zone(z
)) {
2765 if (zone_type
< ZONE_NORMAL
)
2766 low_kmem_size
+= z
->present_pages
;
2767 total_size
+= z
->present_pages
;
2770 if (low_kmem_size
&&
2771 total_size
> average_size
&& /* ignore small node */
2772 low_kmem_size
> total_size
* 70/100)
2773 return ZONELIST_ORDER_NODE
;
2775 return ZONELIST_ORDER_ZONE
;
2778 static void set_zonelist_order(void)
2780 if (user_zonelist_order
== ZONELIST_ORDER_DEFAULT
)
2781 current_zonelist_order
= default_zonelist_order();
2783 current_zonelist_order
= user_zonelist_order
;
2786 static void build_zonelists(pg_data_t
*pgdat
)
2790 nodemask_t used_mask
;
2791 int local_node
, prev_node
;
2792 struct zonelist
*zonelist
;
2793 int order
= current_zonelist_order
;
2795 /* initialize zonelists */
2796 for (i
= 0; i
< MAX_ZONELISTS
; i
++) {
2797 zonelist
= pgdat
->node_zonelists
+ i
;
2798 zonelist
->_zonerefs
[0].zone
= NULL
;
2799 zonelist
->_zonerefs
[0].zone_idx
= 0;
2802 /* NUMA-aware ordering of nodes */
2803 local_node
= pgdat
->node_id
;
2804 load
= nr_online_nodes
;
2805 prev_node
= local_node
;
2806 nodes_clear(used_mask
);
2808 memset(node_order
, 0, sizeof(node_order
));
2811 while ((node
= find_next_best_node(local_node
, &used_mask
)) >= 0) {
2812 int distance
= node_distance(local_node
, node
);
2815 * If another node is sufficiently far away then it is better
2816 * to reclaim pages in a zone before going off node.
2818 if (distance
> RECLAIM_DISTANCE
)
2819 zone_reclaim_mode
= 1;
2822 * We don't want to pressure a particular node.
2823 * So adding penalty to the first node in same
2824 * distance group to make it round-robin.
2826 if (distance
!= node_distance(local_node
, prev_node
))
2827 node_load
[node
] = load
;
2831 if (order
== ZONELIST_ORDER_NODE
)
2832 build_zonelists_in_node_order(pgdat
, node
);
2834 node_order
[j
++] = node
; /* remember order */
2837 if (order
== ZONELIST_ORDER_ZONE
) {
2838 /* calculate node order -- i.e., DMA last! */
2839 build_zonelists_in_zone_order(pgdat
, j
);
2842 build_thisnode_zonelists(pgdat
);
2845 /* Construct the zonelist performance cache - see further mmzone.h */
2846 static void build_zonelist_cache(pg_data_t
*pgdat
)
2848 struct zonelist
*zonelist
;
2849 struct zonelist_cache
*zlc
;
2852 zonelist
= &pgdat
->node_zonelists
[0];
2853 zonelist
->zlcache_ptr
= zlc
= &zonelist
->zlcache
;
2854 bitmap_zero(zlc
->fullzones
, MAX_ZONES_PER_ZONELIST
);
2855 for (z
= zonelist
->_zonerefs
; z
->zone
; z
++)
2856 zlc
->z_to_n
[z
- zonelist
->_zonerefs
] = zonelist_node_idx(z
);
2860 #else /* CONFIG_NUMA */
2862 static void set_zonelist_order(void)
2864 current_zonelist_order
= ZONELIST_ORDER_ZONE
;
2867 static void build_zonelists(pg_data_t
*pgdat
)
2869 int node
, local_node
;
2871 struct zonelist
*zonelist
;
2873 local_node
= pgdat
->node_id
;
2875 zonelist
= &pgdat
->node_zonelists
[0];
2876 j
= build_zonelists_node(pgdat
, zonelist
, 0, MAX_NR_ZONES
- 1);
2879 * Now we build the zonelist so that it contains the zones
2880 * of all the other nodes.
2881 * We don't want to pressure a particular node, so when
2882 * building the zones for node N, we make sure that the
2883 * zones coming right after the local ones are those from
2884 * node N+1 (modulo N)
2886 for (node
= local_node
+ 1; node
< MAX_NUMNODES
; node
++) {
2887 if (!node_online(node
))
2889 j
= build_zonelists_node(NODE_DATA(node
), zonelist
, j
,
2892 for (node
= 0; node
< local_node
; node
++) {
2893 if (!node_online(node
))
2895 j
= build_zonelists_node(NODE_DATA(node
), zonelist
, j
,
2899 zonelist
->_zonerefs
[j
].zone
= NULL
;
2900 zonelist
->_zonerefs
[j
].zone_idx
= 0;
2903 /* non-NUMA variant of zonelist performance cache - just NULL zlcache_ptr */
2904 static void build_zonelist_cache(pg_data_t
*pgdat
)
2906 pgdat
->node_zonelists
[0].zlcache_ptr
= NULL
;
2909 #endif /* CONFIG_NUMA */
2912 * Boot pageset table. One per cpu which is going to be used for all
2913 * zones and all nodes. The parameters will be set in such a way
2914 * that an item put on a list will immediately be handed over to
2915 * the buddy list. This is safe since pageset manipulation is done
2916 * with interrupts disabled.
2918 * The boot_pagesets must be kept even after bootup is complete for
2919 * unused processors and/or zones. They do play a role for bootstrapping
2920 * hotplugged processors.
2922 * zoneinfo_show() and maybe other functions do
2923 * not check if the processor is online before following the pageset pointer.
2924 * Other parts of the kernel may not check if the zone is available.
2926 static void setup_pageset(struct per_cpu_pageset
*p
, unsigned long batch
);
2927 static DEFINE_PER_CPU(struct per_cpu_pageset
, boot_pageset
);
2928 static void setup_zone_pageset(struct zone
*zone
);
2931 * Global mutex to protect against size modification of zonelists
2932 * as well as to serialize pageset setup for the new populated zone.
2934 DEFINE_MUTEX(zonelists_mutex
);
2936 /* return values int ....just for stop_machine() */
2937 static __init_refok
int __build_all_zonelists(void *data
)
2943 memset(node_load
, 0, sizeof(node_load
));
2945 for_each_online_node(nid
) {
2946 pg_data_t
*pgdat
= NODE_DATA(nid
);
2948 build_zonelists(pgdat
);
2949 build_zonelist_cache(pgdat
);
2952 #ifdef CONFIG_MEMORY_HOTPLUG
2953 /* Setup real pagesets for the new zone */
2955 struct zone
*zone
= data
;
2956 setup_zone_pageset(zone
);
2961 * Initialize the boot_pagesets that are going to be used
2962 * for bootstrapping processors. The real pagesets for
2963 * each zone will be allocated later when the per cpu
2964 * allocator is available.
2966 * boot_pagesets are used also for bootstrapping offline
2967 * cpus if the system is already booted because the pagesets
2968 * are needed to initialize allocators on a specific cpu too.
2969 * F.e. the percpu allocator needs the page allocator which
2970 * needs the percpu allocator in order to allocate its pagesets
2971 * (a chicken-egg dilemma).
2973 for_each_possible_cpu(cpu
)
2974 setup_pageset(&per_cpu(boot_pageset
, cpu
), 0);
2980 * Called with zonelists_mutex held always
2981 * unless system_state == SYSTEM_BOOTING.
2983 void build_all_zonelists(void *data
)
2985 set_zonelist_order();
2987 if (system_state
== SYSTEM_BOOTING
) {
2988 __build_all_zonelists(NULL
);
2989 mminit_verify_zonelist();
2990 cpuset_init_current_mems_allowed();
2992 /* we have to stop all cpus to guarantee there is no user
2994 stop_machine(__build_all_zonelists
, data
, NULL
);
2995 /* cpuset refresh routine should be here */
2997 vm_total_pages
= nr_free_pagecache_pages();
2999 * Disable grouping by mobility if the number of pages in the
3000 * system is too low to allow the mechanism to work. It would be
3001 * more accurate, but expensive to check per-zone. This check is
3002 * made on memory-hotadd so a system can start with mobility
3003 * disabled and enable it later
3005 if (vm_total_pages
< (pageblock_nr_pages
* MIGRATE_TYPES
))
3006 page_group_by_mobility_disabled
= 1;
3008 page_group_by_mobility_disabled
= 0;
3010 printk("Built %i zonelists in %s order, mobility grouping %s. "
3011 "Total pages: %ld\n",
3013 zonelist_order_name
[current_zonelist_order
],
3014 page_group_by_mobility_disabled
? "off" : "on",
3017 printk("Policy zone: %s\n", zone_names
[policy_zone
]);
3022 * Helper functions to size the waitqueue hash table.
3023 * Essentially these want to choose hash table sizes sufficiently
3024 * large so that collisions trying to wait on pages are rare.
3025 * But in fact, the number of active page waitqueues on typical
3026 * systems is ridiculously low, less than 200. So this is even
3027 * conservative, even though it seems large.
3029 * The constant PAGES_PER_WAITQUEUE specifies the ratio of pages to
3030 * waitqueues, i.e. the size of the waitq table given the number of pages.
3032 #define PAGES_PER_WAITQUEUE 256
3034 #ifndef CONFIG_MEMORY_HOTPLUG
3035 static inline unsigned long wait_table_hash_nr_entries(unsigned long pages
)
3037 unsigned long size
= 1;
3039 pages
/= PAGES_PER_WAITQUEUE
;
3041 while (size
< pages
)
3045 * Once we have dozens or even hundreds of threads sleeping
3046 * on IO we've got bigger problems than wait queue collision.
3047 * Limit the size of the wait table to a reasonable size.
3049 size
= min(size
, 4096UL);
3051 return max(size
, 4UL);
3055 * A zone's size might be changed by hot-add, so it is not possible to determine
3056 * a suitable size for its wait_table. So we use the maximum size now.
3058 * The max wait table size = 4096 x sizeof(wait_queue_head_t). ie:
3060 * i386 (preemption config) : 4096 x 16 = 64Kbyte.
3061 * ia64, x86-64 (no preemption): 4096 x 20 = 80Kbyte.
3062 * ia64, x86-64 (preemption) : 4096 x 24 = 96Kbyte.
3064 * The maximum entries are prepared when a zone's memory is (512K + 256) pages
3065 * or more by the traditional way. (See above). It equals:
3067 * i386, x86-64, powerpc(4K page size) : = ( 2G + 1M)byte.
3068 * ia64(16K page size) : = ( 8G + 4M)byte.
3069 * powerpc (64K page size) : = (32G +16M)byte.
3071 static inline unsigned long wait_table_hash_nr_entries(unsigned long pages
)
3078 * This is an integer logarithm so that shifts can be used later
3079 * to extract the more random high bits from the multiplicative
3080 * hash function before the remainder is taken.
3082 static inline unsigned long wait_table_bits(unsigned long size
)
3087 #define LONG_ALIGN(x) (((x)+(sizeof(long))-1)&~((sizeof(long))-1))
3090 * Mark a number of pageblocks as MIGRATE_RESERVE. The number
3091 * of blocks reserved is based on min_wmark_pages(zone). The memory within
3092 * the reserve will tend to store contiguous free pages. Setting min_free_kbytes
3093 * higher will lead to a bigger reserve which will get freed as contiguous
3094 * blocks as reclaim kicks in
3096 static void setup_zone_migrate_reserve(struct zone
*zone
)
3098 unsigned long start_pfn
, pfn
, end_pfn
;
3100 unsigned long block_migratetype
;
3103 /* Get the start pfn, end pfn and the number of blocks to reserve */
3104 start_pfn
= zone
->zone_start_pfn
;
3105 end_pfn
= start_pfn
+ zone
->spanned_pages
;
3106 reserve
= roundup(min_wmark_pages(zone
), pageblock_nr_pages
) >>
3110 * Reserve blocks are generally in place to help high-order atomic
3111 * allocations that are short-lived. A min_free_kbytes value that
3112 * would result in more than 2 reserve blocks for atomic allocations
3113 * is assumed to be in place to help anti-fragmentation for the
3114 * future allocation of hugepages at runtime.
3116 reserve
= min(2, reserve
);
3118 for (pfn
= start_pfn
; pfn
< end_pfn
; pfn
+= pageblock_nr_pages
) {
3119 if (!pfn_valid(pfn
))
3121 page
= pfn_to_page(pfn
);
3123 /* Watch out for overlapping nodes */
3124 if (page_to_nid(page
) != zone_to_nid(zone
))
3127 /* Blocks with reserved pages will never free, skip them. */
3128 if (PageReserved(page
))
3131 block_migratetype
= get_pageblock_migratetype(page
);
3133 /* If this block is reserved, account for it */
3134 if (reserve
> 0 && block_migratetype
== MIGRATE_RESERVE
) {
3139 /* Suitable for reserving if this block is movable */
3140 if (reserve
> 0 && block_migratetype
== MIGRATE_MOVABLE
) {
3141 set_pageblock_migratetype(page
, MIGRATE_RESERVE
);
3142 move_freepages_block(zone
, page
, MIGRATE_RESERVE
);
3148 * If the reserve is met and this is a previous reserved block,
3151 if (block_migratetype
== MIGRATE_RESERVE
) {
3152 set_pageblock_migratetype(page
, MIGRATE_MOVABLE
);
3153 move_freepages_block(zone
, page
, MIGRATE_MOVABLE
);
3159 * Initially all pages are reserved - free ones are freed
3160 * up by free_all_bootmem() once the early boot process is
3161 * done. Non-atomic initialization, single-pass.
3163 void __meminit
memmap_init_zone(unsigned long size
, int nid
, unsigned long zone
,
3164 unsigned long start_pfn
, enum memmap_context context
)
3167 unsigned long end_pfn
= start_pfn
+ size
;
3171 if (highest_memmap_pfn
< end_pfn
- 1)
3172 highest_memmap_pfn
= end_pfn
- 1;
3174 z
= &NODE_DATA(nid
)->node_zones
[zone
];
3175 for (pfn
= start_pfn
; pfn
< end_pfn
; pfn
++) {
3177 * There can be holes in boot-time mem_map[]s
3178 * handed to this function. They do not
3179 * exist on hotplugged memory.
3181 if (context
== MEMMAP_EARLY
) {
3182 if (!early_pfn_valid(pfn
))
3184 if (!early_pfn_in_nid(pfn
, nid
))
3187 page
= pfn_to_page(pfn
);
3188 set_page_links(page
, zone
, nid
, pfn
);
3189 mminit_verify_page_links(page
, zone
, nid
, pfn
);
3190 init_page_count(page
);
3191 reset_page_mapcount(page
);
3192 SetPageReserved(page
);
3194 * Mark the block movable so that blocks are reserved for
3195 * movable at startup. This will force kernel allocations
3196 * to reserve their blocks rather than leaking throughout
3197 * the address space during boot when many long-lived
3198 * kernel allocations are made. Later some blocks near
3199 * the start are marked MIGRATE_RESERVE by
3200 * setup_zone_migrate_reserve()
3202 * bitmap is created for zone's valid pfn range. but memmap
3203 * can be created for invalid pages (for alignment)
3204 * check here not to call set_pageblock_migratetype() against
3207 if ((z
->zone_start_pfn
<= pfn
)
3208 && (pfn
< z
->zone_start_pfn
+ z
->spanned_pages
)
3209 && !(pfn
& (pageblock_nr_pages
- 1)))
3210 set_pageblock_migratetype(page
, MIGRATE_MOVABLE
);
3212 INIT_LIST_HEAD(&page
->lru
);
3213 #ifdef WANT_PAGE_VIRTUAL
3214 /* The shift won't overflow because ZONE_NORMAL is below 4G. */
3215 if (!is_highmem_idx(zone
))
3216 set_page_address(page
, __va(pfn
<< PAGE_SHIFT
));
3221 static void __meminit
zone_init_free_lists(struct zone
*zone
)
3224 for_each_migratetype_order(order
, t
) {
3225 INIT_LIST_HEAD(&zone
->free_area
[order
].free_list
[t
]);
3226 zone
->free_area
[order
].nr_free
= 0;
3230 #ifndef __HAVE_ARCH_MEMMAP_INIT
3231 #define memmap_init(size, nid, zone, start_pfn) \
3232 memmap_init_zone((size), (nid), (zone), (start_pfn), MEMMAP_EARLY)
3235 static int zone_batchsize(struct zone
*zone
)
3241 * The per-cpu-pages pools are set to around 1000th of the
3242 * size of the zone. But no more than 1/2 of a meg.
3244 * OK, so we don't know how big the cache is. So guess.
3246 batch
= zone
->present_pages
/ 1024;
3247 if (batch
* PAGE_SIZE
> 512 * 1024)
3248 batch
= (512 * 1024) / PAGE_SIZE
;
3249 batch
/= 4; /* We effectively *= 4 below */
3254 * Clamp the batch to a 2^n - 1 value. Having a power
3255 * of 2 value was found to be more likely to have
3256 * suboptimal cache aliasing properties in some cases.
3258 * For example if 2 tasks are alternately allocating
3259 * batches of pages, one task can end up with a lot
3260 * of pages of one half of the possible page colors
3261 * and the other with pages of the other colors.
3263 batch
= rounddown_pow_of_two(batch
+ batch
/2) - 1;
3268 /* The deferral and batching of frees should be suppressed under NOMMU
3271 * The problem is that NOMMU needs to be able to allocate large chunks
3272 * of contiguous memory as there's no hardware page translation to
3273 * assemble apparent contiguous memory from discontiguous pages.
3275 * Queueing large contiguous runs of pages for batching, however,
3276 * causes the pages to actually be freed in smaller chunks. As there
3277 * can be a significant delay between the individual batches being
3278 * recycled, this leads to the once large chunks of space being
3279 * fragmented and becoming unavailable for high-order allocations.
3285 static void setup_pageset(struct per_cpu_pageset
*p
, unsigned long batch
)
3287 struct per_cpu_pages
*pcp
;
3290 memset(p
, 0, sizeof(*p
));
3294 pcp
->high
= 6 * batch
;
3295 pcp
->batch
= max(1UL, 1 * batch
);
3296 for (migratetype
= 0; migratetype
< MIGRATE_PCPTYPES
; migratetype
++)
3297 INIT_LIST_HEAD(&pcp
->lists
[migratetype
]);
3301 * setup_pagelist_highmark() sets the high water mark for hot per_cpu_pagelist
3302 * to the value high for the pageset p.
3305 static void setup_pagelist_highmark(struct per_cpu_pageset
*p
,
3308 struct per_cpu_pages
*pcp
;
3312 pcp
->batch
= max(1UL, high
/4);
3313 if ((high
/4) > (PAGE_SHIFT
* 8))
3314 pcp
->batch
= PAGE_SHIFT
* 8;
3317 static __meminit
void setup_zone_pageset(struct zone
*zone
)
3321 zone
->pageset
= alloc_percpu(struct per_cpu_pageset
);
3323 for_each_possible_cpu(cpu
) {
3324 struct per_cpu_pageset
*pcp
= per_cpu_ptr(zone
->pageset
, cpu
);
3326 setup_pageset(pcp
, zone_batchsize(zone
));
3328 if (percpu_pagelist_fraction
)
3329 setup_pagelist_highmark(pcp
,
3330 (zone
->present_pages
/
3331 percpu_pagelist_fraction
));
3336 * Allocate per cpu pagesets and initialize them.
3337 * Before this call only boot pagesets were available.
3339 void __init
setup_per_cpu_pageset(void)
3343 for_each_populated_zone(zone
)
3344 setup_zone_pageset(zone
);
3347 static noinline __init_refok
3348 int zone_wait_table_init(struct zone
*zone
, unsigned long zone_size_pages
)
3351 struct pglist_data
*pgdat
= zone
->zone_pgdat
;
3355 * The per-page waitqueue mechanism uses hashed waitqueues
3358 zone
->wait_table_hash_nr_entries
=
3359 wait_table_hash_nr_entries(zone_size_pages
);
3360 zone
->wait_table_bits
=
3361 wait_table_bits(zone
->wait_table_hash_nr_entries
);
3362 alloc_size
= zone
->wait_table_hash_nr_entries
3363 * sizeof(wait_queue_head_t
);
3365 if (!slab_is_available()) {
3366 zone
->wait_table
= (wait_queue_head_t
*)
3367 alloc_bootmem_node(pgdat
, alloc_size
);
3370 * This case means that a zone whose size was 0 gets new memory
3371 * via memory hot-add.
3372 * But it may be the case that a new node was hot-added. In
3373 * this case vmalloc() will not be able to use this new node's
3374 * memory - this wait_table must be initialized to use this new
3375 * node itself as well.
3376 * To use this new node's memory, further consideration will be
3379 zone
->wait_table
= vmalloc(alloc_size
);
3381 if (!zone
->wait_table
)
3384 for(i
= 0; i
< zone
->wait_table_hash_nr_entries
; ++i
)
3385 init_waitqueue_head(zone
->wait_table
+ i
);
3390 static int __zone_pcp_update(void *data
)
3392 struct zone
*zone
= data
;
3394 unsigned long batch
= zone_batchsize(zone
), flags
;
3396 for_each_possible_cpu(cpu
) {
3397 struct per_cpu_pageset
*pset
;
3398 struct per_cpu_pages
*pcp
;
3400 pset
= per_cpu_ptr(zone
->pageset
, cpu
);
3403 local_irq_save(flags
);
3404 free_pcppages_bulk(zone
, pcp
->count
, pcp
);
3405 setup_pageset(pset
, batch
);
3406 local_irq_restore(flags
);
3411 void zone_pcp_update(struct zone
*zone
)
3413 stop_machine(__zone_pcp_update
, zone
, NULL
);
3416 static __meminit
void zone_pcp_init(struct zone
*zone
)
3419 * per cpu subsystem is not up at this point. The following code
3420 * relies on the ability of the linker to provide the
3421 * offset of a (static) per cpu variable into the per cpu area.
3423 zone
->pageset
= &boot_pageset
;
3425 if (zone
->present_pages
)
3426 printk(KERN_DEBUG
" %s zone: %lu pages, LIFO batch:%u\n",
3427 zone
->name
, zone
->present_pages
,
3428 zone_batchsize(zone
));
3431 __meminit
int init_currently_empty_zone(struct zone
*zone
,
3432 unsigned long zone_start_pfn
,
3434 enum memmap_context context
)
3436 struct pglist_data
*pgdat
= zone
->zone_pgdat
;
3438 ret
= zone_wait_table_init(zone
, size
);
3441 pgdat
->nr_zones
= zone_idx(zone
) + 1;
3443 zone
->zone_start_pfn
= zone_start_pfn
;
3445 mminit_dprintk(MMINIT_TRACE
, "memmap_init",
3446 "Initialising map node %d zone %lu pfns %lu -> %lu\n",
3448 (unsigned long)zone_idx(zone
),
3449 zone_start_pfn
, (zone_start_pfn
+ size
));
3451 zone_init_free_lists(zone
);
3456 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
3458 * Basic iterator support. Return the first range of PFNs for a node
3459 * Note: nid == MAX_NUMNODES returns first region regardless of node
3461 static int __meminit
first_active_region_index_in_nid(int nid
)
3465 for (i
= 0; i
< nr_nodemap_entries
; i
++)
3466 if (nid
== MAX_NUMNODES
|| early_node_map
[i
].nid
== nid
)
3473 * Basic iterator support. Return the next active range of PFNs for a node
3474 * Note: nid == MAX_NUMNODES returns next region regardless of node
3476 static int __meminit
next_active_region_index_in_nid(int index
, int nid
)
3478 for (index
= index
+ 1; index
< nr_nodemap_entries
; index
++)
3479 if (nid
== MAX_NUMNODES
|| early_node_map
[index
].nid
== nid
)
3485 #ifndef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
3487 * Required by SPARSEMEM. Given a PFN, return what node the PFN is on.
3488 * Architectures may implement their own version but if add_active_range()
3489 * was used and there are no special requirements, this is a convenient
3492 int __meminit
__early_pfn_to_nid(unsigned long pfn
)
3496 for (i
= 0; i
< nr_nodemap_entries
; i
++) {
3497 unsigned long start_pfn
= early_node_map
[i
].start_pfn
;
3498 unsigned long end_pfn
= early_node_map
[i
].end_pfn
;
3500 if (start_pfn
<= pfn
&& pfn
< end_pfn
)
3501 return early_node_map
[i
].nid
;
3503 /* This is a memory hole */
3506 #endif /* CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID */
3508 int __meminit
early_pfn_to_nid(unsigned long pfn
)
3512 nid
= __early_pfn_to_nid(pfn
);
3515 /* just returns 0 */
3519 #ifdef CONFIG_NODES_SPAN_OTHER_NODES
3520 bool __meminit
early_pfn_in_nid(unsigned long pfn
, int node
)
3524 nid
= __early_pfn_to_nid(pfn
);
3525 if (nid
>= 0 && nid
!= node
)
3531 /* Basic iterator support to walk early_node_map[] */
3532 #define for_each_active_range_index_in_nid(i, nid) \
3533 for (i = first_active_region_index_in_nid(nid); i != -1; \
3534 i = next_active_region_index_in_nid(i, nid))
3537 * free_bootmem_with_active_regions - Call free_bootmem_node for each active range
3538 * @nid: The node to free memory on. If MAX_NUMNODES, all nodes are freed.
3539 * @max_low_pfn: The highest PFN that will be passed to free_bootmem_node
3541 * If an architecture guarantees that all ranges registered with
3542 * add_active_ranges() contain no holes and may be freed, this
3543 * this function may be used instead of calling free_bootmem() manually.
3545 void __init
free_bootmem_with_active_regions(int nid
,
3546 unsigned long max_low_pfn
)
3550 for_each_active_range_index_in_nid(i
, nid
) {
3551 unsigned long size_pages
= 0;
3552 unsigned long end_pfn
= early_node_map
[i
].end_pfn
;
3554 if (early_node_map
[i
].start_pfn
>= max_low_pfn
)
3557 if (end_pfn
> max_low_pfn
)
3558 end_pfn
= max_low_pfn
;
3560 size_pages
= end_pfn
- early_node_map
[i
].start_pfn
;
3561 free_bootmem_node(NODE_DATA(early_node_map
[i
].nid
),
3562 PFN_PHYS(early_node_map
[i
].start_pfn
),
3563 size_pages
<< PAGE_SHIFT
);
3567 int __init
add_from_early_node_map(struct range
*range
, int az
,
3568 int nr_range
, int nid
)
3573 /* need to go over early_node_map to find out good range for node */
3574 for_each_active_range_index_in_nid(i
, nid
) {
3575 start
= early_node_map
[i
].start_pfn
;
3576 end
= early_node_map
[i
].end_pfn
;
3577 nr_range
= add_range(range
, az
, nr_range
, start
, end
);
3582 #ifdef CONFIG_NO_BOOTMEM
3583 void * __init
__alloc_memory_core_early(int nid
, u64 size
, u64 align
,
3584 u64 goal
, u64 limit
)
3589 /* need to go over early_node_map to find out good range for node */
3590 for_each_active_range_index_in_nid(i
, nid
) {
3592 u64 ei_start
, ei_last
;
3594 ei_last
= early_node_map
[i
].end_pfn
;
3595 ei_last
<<= PAGE_SHIFT
;
3596 ei_start
= early_node_map
[i
].start_pfn
;
3597 ei_start
<<= PAGE_SHIFT
;
3598 addr
= find_early_area(ei_start
, ei_last
,
3599 goal
, limit
, size
, align
);
3605 printk(KERN_DEBUG
"alloc (nid=%d %llx - %llx) (%llx - %llx) %llx %llx => %llx\n",
3607 ei_start
, ei_last
, goal
, limit
, size
,
3611 ptr
= phys_to_virt(addr
);
3612 memset(ptr
, 0, size
);
3613 reserve_early_without_check(addr
, addr
+ size
, "BOOTMEM");
3622 void __init
work_with_active_regions(int nid
, work_fn_t work_fn
, void *data
)
3627 for_each_active_range_index_in_nid(i
, nid
) {
3628 ret
= work_fn(early_node_map
[i
].start_pfn
,
3629 early_node_map
[i
].end_pfn
, data
);
3635 * sparse_memory_present_with_active_regions - Call memory_present for each active range
3636 * @nid: The node to call memory_present for. If MAX_NUMNODES, all nodes will be used.
3638 * If an architecture guarantees that all ranges registered with
3639 * add_active_ranges() contain no holes and may be freed, this
3640 * function may be used instead of calling memory_present() manually.
3642 void __init
sparse_memory_present_with_active_regions(int nid
)
3646 for_each_active_range_index_in_nid(i
, nid
)
3647 memory_present(early_node_map
[i
].nid
,
3648 early_node_map
[i
].start_pfn
,
3649 early_node_map
[i
].end_pfn
);
3653 * get_pfn_range_for_nid - Return the start and end page frames for a node
3654 * @nid: The nid to return the range for. If MAX_NUMNODES, the min and max PFN are returned.
3655 * @start_pfn: Passed by reference. On return, it will have the node start_pfn.
3656 * @end_pfn: Passed by reference. On return, it will have the node end_pfn.
3658 * It returns the start and end page frame of a node based on information
3659 * provided by an arch calling add_active_range(). If called for a node
3660 * with no available memory, a warning is printed and the start and end
3663 void __meminit
get_pfn_range_for_nid(unsigned int nid
,
3664 unsigned long *start_pfn
, unsigned long *end_pfn
)
3670 for_each_active_range_index_in_nid(i
, nid
) {
3671 *start_pfn
= min(*start_pfn
, early_node_map
[i
].start_pfn
);
3672 *end_pfn
= max(*end_pfn
, early_node_map
[i
].end_pfn
);
3675 if (*start_pfn
== -1UL)
3680 * This finds a zone that can be used for ZONE_MOVABLE pages. The
3681 * assumption is made that zones within a node are ordered in monotonic
3682 * increasing memory addresses so that the "highest" populated zone is used
3684 static void __init
find_usable_zone_for_movable(void)
3687 for (zone_index
= MAX_NR_ZONES
- 1; zone_index
>= 0; zone_index
--) {
3688 if (zone_index
== ZONE_MOVABLE
)
3691 if (arch_zone_highest_possible_pfn
[zone_index
] >
3692 arch_zone_lowest_possible_pfn
[zone_index
])
3696 VM_BUG_ON(zone_index
== -1);
3697 movable_zone
= zone_index
;
3701 * The zone ranges provided by the architecture do not include ZONE_MOVABLE
3702 * because it is sized independant of architecture. Unlike the other zones,
3703 * the starting point for ZONE_MOVABLE is not fixed. It may be different
3704 * in each node depending on the size of each node and how evenly kernelcore
3705 * is distributed. This helper function adjusts the zone ranges
3706 * provided by the architecture for a given node by using the end of the
3707 * highest usable zone for ZONE_MOVABLE. This preserves the assumption that
3708 * zones within a node are in order of monotonic increases memory addresses
3710 static void __meminit
adjust_zone_range_for_zone_movable(int nid
,
3711 unsigned long zone_type
,
3712 unsigned long node_start_pfn
,
3713 unsigned long node_end_pfn
,
3714 unsigned long *zone_start_pfn
,
3715 unsigned long *zone_end_pfn
)
3717 /* Only adjust if ZONE_MOVABLE is on this node */
3718 if (zone_movable_pfn
[nid
]) {
3719 /* Size ZONE_MOVABLE */
3720 if (zone_type
== ZONE_MOVABLE
) {
3721 *zone_start_pfn
= zone_movable_pfn
[nid
];
3722 *zone_end_pfn
= min(node_end_pfn
,
3723 arch_zone_highest_possible_pfn
[movable_zone
]);
3725 /* Adjust for ZONE_MOVABLE starting within this range */
3726 } else if (*zone_start_pfn
< zone_movable_pfn
[nid
] &&
3727 *zone_end_pfn
> zone_movable_pfn
[nid
]) {
3728 *zone_end_pfn
= zone_movable_pfn
[nid
];
3730 /* Check if this whole range is within ZONE_MOVABLE */
3731 } else if (*zone_start_pfn
>= zone_movable_pfn
[nid
])
3732 *zone_start_pfn
= *zone_end_pfn
;
3737 * Return the number of pages a zone spans in a node, including holes
3738 * present_pages = zone_spanned_pages_in_node() - zone_absent_pages_in_node()
3740 static unsigned long __meminit
zone_spanned_pages_in_node(int nid
,
3741 unsigned long zone_type
,
3742 unsigned long *ignored
)
3744 unsigned long node_start_pfn
, node_end_pfn
;
3745 unsigned long zone_start_pfn
, zone_end_pfn
;
3747 /* Get the start and end of the node and zone */
3748 get_pfn_range_for_nid(nid
, &node_start_pfn
, &node_end_pfn
);
3749 zone_start_pfn
= arch_zone_lowest_possible_pfn
[zone_type
];
3750 zone_end_pfn
= arch_zone_highest_possible_pfn
[zone_type
];
3751 adjust_zone_range_for_zone_movable(nid
, zone_type
,
3752 node_start_pfn
, node_end_pfn
,
3753 &zone_start_pfn
, &zone_end_pfn
);
3755 /* Check that this node has pages within the zone's required range */
3756 if (zone_end_pfn
< node_start_pfn
|| zone_start_pfn
> node_end_pfn
)
3759 /* Move the zone boundaries inside the node if necessary */
3760 zone_end_pfn
= min(zone_end_pfn
, node_end_pfn
);
3761 zone_start_pfn
= max(zone_start_pfn
, node_start_pfn
);
3763 /* Return the spanned pages */
3764 return zone_end_pfn
- zone_start_pfn
;
3768 * Return the number of holes in a range on a node. If nid is MAX_NUMNODES,
3769 * then all holes in the requested range will be accounted for.
3771 unsigned long __meminit
__absent_pages_in_range(int nid
,
3772 unsigned long range_start_pfn
,
3773 unsigned long range_end_pfn
)
3776 unsigned long prev_end_pfn
= 0, hole_pages
= 0;
3777 unsigned long start_pfn
;
3779 /* Find the end_pfn of the first active range of pfns in the node */
3780 i
= first_active_region_index_in_nid(nid
);
3784 prev_end_pfn
= min(early_node_map
[i
].start_pfn
, range_end_pfn
);
3786 /* Account for ranges before physical memory on this node */
3787 if (early_node_map
[i
].start_pfn
> range_start_pfn
)
3788 hole_pages
= prev_end_pfn
- range_start_pfn
;
3790 /* Find all holes for the zone within the node */
3791 for (; i
!= -1; i
= next_active_region_index_in_nid(i
, nid
)) {
3793 /* No need to continue if prev_end_pfn is outside the zone */
3794 if (prev_end_pfn
>= range_end_pfn
)
3797 /* Make sure the end of the zone is not within the hole */
3798 start_pfn
= min(early_node_map
[i
].start_pfn
, range_end_pfn
);
3799 prev_end_pfn
= max(prev_end_pfn
, range_start_pfn
);
3801 /* Update the hole size cound and move on */
3802 if (start_pfn
> range_start_pfn
) {
3803 BUG_ON(prev_end_pfn
> start_pfn
);
3804 hole_pages
+= start_pfn
- prev_end_pfn
;
3806 prev_end_pfn
= early_node_map
[i
].end_pfn
;
3809 /* Account for ranges past physical memory on this node */
3810 if (range_end_pfn
> prev_end_pfn
)
3811 hole_pages
+= range_end_pfn
-
3812 max(range_start_pfn
, prev_end_pfn
);
3818 * absent_pages_in_range - Return number of page frames in holes within a range
3819 * @start_pfn: The start PFN to start searching for holes
3820 * @end_pfn: The end PFN to stop searching for holes
3822 * It returns the number of pages frames in memory holes within a range.
3824 unsigned long __init
absent_pages_in_range(unsigned long start_pfn
,
3825 unsigned long end_pfn
)
3827 return __absent_pages_in_range(MAX_NUMNODES
, start_pfn
, end_pfn
);
3830 /* Return the number of page frames in holes in a zone on a node */
3831 static unsigned long __meminit
zone_absent_pages_in_node(int nid
,
3832 unsigned long zone_type
,
3833 unsigned long *ignored
)
3835 unsigned long node_start_pfn
, node_end_pfn
;
3836 unsigned long zone_start_pfn
, zone_end_pfn
;
3838 get_pfn_range_for_nid(nid
, &node_start_pfn
, &node_end_pfn
);
3839 zone_start_pfn
= max(arch_zone_lowest_possible_pfn
[zone_type
],
3841 zone_end_pfn
= min(arch_zone_highest_possible_pfn
[zone_type
],
3844 adjust_zone_range_for_zone_movable(nid
, zone_type
,
3845 node_start_pfn
, node_end_pfn
,
3846 &zone_start_pfn
, &zone_end_pfn
);
3847 return __absent_pages_in_range(nid
, zone_start_pfn
, zone_end_pfn
);
3851 static inline unsigned long __meminit
zone_spanned_pages_in_node(int nid
,
3852 unsigned long zone_type
,
3853 unsigned long *zones_size
)
3855 return zones_size
[zone_type
];
3858 static inline unsigned long __meminit
zone_absent_pages_in_node(int nid
,
3859 unsigned long zone_type
,
3860 unsigned long *zholes_size
)
3865 return zholes_size
[zone_type
];
3870 static void __meminit
calculate_node_totalpages(struct pglist_data
*pgdat
,
3871 unsigned long *zones_size
, unsigned long *zholes_size
)
3873 unsigned long realtotalpages
, totalpages
= 0;
3876 for (i
= 0; i
< MAX_NR_ZONES
; i
++)
3877 totalpages
+= zone_spanned_pages_in_node(pgdat
->node_id
, i
,
3879 pgdat
->node_spanned_pages
= totalpages
;
3881 realtotalpages
= totalpages
;
3882 for (i
= 0; i
< MAX_NR_ZONES
; i
++)
3884 zone_absent_pages_in_node(pgdat
->node_id
, i
,
3886 pgdat
->node_present_pages
= realtotalpages
;
3887 printk(KERN_DEBUG
"On node %d totalpages: %lu\n", pgdat
->node_id
,
3891 #ifndef CONFIG_SPARSEMEM
3893 * Calculate the size of the zone->blockflags rounded to an unsigned long
3894 * Start by making sure zonesize is a multiple of pageblock_order by rounding
3895 * up. Then use 1 NR_PAGEBLOCK_BITS worth of bits per pageblock, finally
3896 * round what is now in bits to nearest long in bits, then return it in
3899 static unsigned long __init
usemap_size(unsigned long zonesize
)
3901 unsigned long usemapsize
;
3903 usemapsize
= roundup(zonesize
, pageblock_nr_pages
);
3904 usemapsize
= usemapsize
>> pageblock_order
;
3905 usemapsize
*= NR_PAGEBLOCK_BITS
;
3906 usemapsize
= roundup(usemapsize
, 8 * sizeof(unsigned long));
3908 return usemapsize
/ 8;
3911 static void __init
setup_usemap(struct pglist_data
*pgdat
,
3912 struct zone
*zone
, unsigned long zonesize
)
3914 unsigned long usemapsize
= usemap_size(zonesize
);
3915 zone
->pageblock_flags
= NULL
;
3917 zone
->pageblock_flags
= alloc_bootmem_node(pgdat
, usemapsize
);
3920 static void inline setup_usemap(struct pglist_data
*pgdat
,
3921 struct zone
*zone
, unsigned long zonesize
) {}
3922 #endif /* CONFIG_SPARSEMEM */
3924 #ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
3926 /* Return a sensible default order for the pageblock size. */
3927 static inline int pageblock_default_order(void)
3929 if (HPAGE_SHIFT
> PAGE_SHIFT
)
3930 return HUGETLB_PAGE_ORDER
;
3935 /* Initialise the number of pages represented by NR_PAGEBLOCK_BITS */
3936 static inline void __init
set_pageblock_order(unsigned int order
)
3938 /* Check that pageblock_nr_pages has not already been setup */
3939 if (pageblock_order
)
3943 * Assume the largest contiguous order of interest is a huge page.
3944 * This value may be variable depending on boot parameters on IA64
3946 pageblock_order
= order
;
3948 #else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
3951 * When CONFIG_HUGETLB_PAGE_SIZE_VARIABLE is not set, set_pageblock_order()
3952 * and pageblock_default_order() are unused as pageblock_order is set
3953 * at compile-time. See include/linux/pageblock-flags.h for the values of
3954 * pageblock_order based on the kernel config
3956 static inline int pageblock_default_order(unsigned int order
)
3960 #define set_pageblock_order(x) do {} while (0)
3962 #endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
3965 * Set up the zone data structures:
3966 * - mark all pages reserved
3967 * - mark all memory queues empty
3968 * - clear the memory bitmaps
3970 static void __paginginit
free_area_init_core(struct pglist_data
*pgdat
,
3971 unsigned long *zones_size
, unsigned long *zholes_size
)
3974 int nid
= pgdat
->node_id
;
3975 unsigned long zone_start_pfn
= pgdat
->node_start_pfn
;
3978 pgdat_resize_init(pgdat
);
3979 pgdat
->nr_zones
= 0;
3980 init_waitqueue_head(&pgdat
->kswapd_wait
);
3981 pgdat
->kswapd_max_order
= 0;
3982 pgdat_page_cgroup_init(pgdat
);
3984 for (j
= 0; j
< MAX_NR_ZONES
; j
++) {
3985 struct zone
*zone
= pgdat
->node_zones
+ j
;
3986 unsigned long size
, realsize
, memmap_pages
;
3989 size
= zone_spanned_pages_in_node(nid
, j
, zones_size
);
3990 realsize
= size
- zone_absent_pages_in_node(nid
, j
,
3994 * Adjust realsize so that it accounts for how much memory
3995 * is used by this zone for memmap. This affects the watermark
3996 * and per-cpu initialisations
3999 PAGE_ALIGN(size
* sizeof(struct page
)) >> PAGE_SHIFT
;
4000 if (realsize
>= memmap_pages
) {
4001 realsize
-= memmap_pages
;
4004 " %s zone: %lu pages used for memmap\n",
4005 zone_names
[j
], memmap_pages
);
4008 " %s zone: %lu pages exceeds realsize %lu\n",
4009 zone_names
[j
], memmap_pages
, realsize
);
4011 /* Account for reserved pages */
4012 if (j
== 0 && realsize
> dma_reserve
) {
4013 realsize
-= dma_reserve
;
4014 printk(KERN_DEBUG
" %s zone: %lu pages reserved\n",
4015 zone_names
[0], dma_reserve
);
4018 if (!is_highmem_idx(j
))
4019 nr_kernel_pages
+= realsize
;
4020 nr_all_pages
+= realsize
;
4022 zone
->spanned_pages
= size
;
4023 zone
->present_pages
= realsize
;
4026 zone
->min_unmapped_pages
= (realsize
*sysctl_min_unmapped_ratio
)
4028 zone
->min_slab_pages
= (realsize
* sysctl_min_slab_ratio
) / 100;
4030 zone
->name
= zone_names
[j
];
4031 spin_lock_init(&zone
->lock
);
4032 spin_lock_init(&zone
->lru_lock
);
4033 zone_seqlock_init(zone
);
4034 zone
->zone_pgdat
= pgdat
;
4036 zone
->prev_priority
= DEF_PRIORITY
;
4038 zone_pcp_init(zone
);
4040 INIT_LIST_HEAD(&zone
->lru
[l
].list
);
4041 zone
->reclaim_stat
.nr_saved_scan
[l
] = 0;
4043 zone
->reclaim_stat
.recent_rotated
[0] = 0;
4044 zone
->reclaim_stat
.recent_rotated
[1] = 0;
4045 zone
->reclaim_stat
.recent_scanned
[0] = 0;
4046 zone
->reclaim_stat
.recent_scanned
[1] = 0;
4047 zap_zone_vm_stats(zone
);
4052 set_pageblock_order(pageblock_default_order());
4053 setup_usemap(pgdat
, zone
, size
);
4054 ret
= init_currently_empty_zone(zone
, zone_start_pfn
,
4055 size
, MEMMAP_EARLY
);
4057 memmap_init(size
, nid
, j
, zone_start_pfn
);
4058 zone_start_pfn
+= size
;
4062 static void __init_refok
alloc_node_mem_map(struct pglist_data
*pgdat
)
4064 /* Skip empty nodes */
4065 if (!pgdat
->node_spanned_pages
)
4068 #ifdef CONFIG_FLAT_NODE_MEM_MAP
4069 /* ia64 gets its own node_mem_map, before this, without bootmem */
4070 if (!pgdat
->node_mem_map
) {
4071 unsigned long size
, start
, end
;
4075 * The zone's endpoints aren't required to be MAX_ORDER
4076 * aligned but the node_mem_map endpoints must be in order
4077 * for the buddy allocator to function correctly.
4079 start
= pgdat
->node_start_pfn
& ~(MAX_ORDER_NR_PAGES
- 1);
4080 end
= pgdat
->node_start_pfn
+ pgdat
->node_spanned_pages
;
4081 end
= ALIGN(end
, MAX_ORDER_NR_PAGES
);
4082 size
= (end
- start
) * sizeof(struct page
);
4083 map
= alloc_remap(pgdat
->node_id
, size
);
4085 map
= alloc_bootmem_node(pgdat
, size
);
4086 pgdat
->node_mem_map
= map
+ (pgdat
->node_start_pfn
- start
);
4088 #ifndef CONFIG_NEED_MULTIPLE_NODES
4090 * With no DISCONTIG, the global mem_map is just set as node 0's
4092 if (pgdat
== NODE_DATA(0)) {
4093 mem_map
= NODE_DATA(0)->node_mem_map
;
4094 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
4095 if (page_to_pfn(mem_map
) != pgdat
->node_start_pfn
)
4096 mem_map
-= (pgdat
->node_start_pfn
- ARCH_PFN_OFFSET
);
4097 #endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
4100 #endif /* CONFIG_FLAT_NODE_MEM_MAP */
4103 void __paginginit
free_area_init_node(int nid
, unsigned long *zones_size
,
4104 unsigned long node_start_pfn
, unsigned long *zholes_size
)
4106 pg_data_t
*pgdat
= NODE_DATA(nid
);
4108 pgdat
->node_id
= nid
;
4109 pgdat
->node_start_pfn
= node_start_pfn
;
4110 calculate_node_totalpages(pgdat
, zones_size
, zholes_size
);
4112 alloc_node_mem_map(pgdat
);
4113 #ifdef CONFIG_FLAT_NODE_MEM_MAP
4114 printk(KERN_DEBUG
"free_area_init_node: node %d, pgdat %08lx, node_mem_map %08lx\n",
4115 nid
, (unsigned long)pgdat
,
4116 (unsigned long)pgdat
->node_mem_map
);
4119 free_area_init_core(pgdat
, zones_size
, zholes_size
);
4122 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
4124 #if MAX_NUMNODES > 1
4126 * Figure out the number of possible node ids.
4128 static void __init
setup_nr_node_ids(void)
4131 unsigned int highest
= 0;
4133 for_each_node_mask(node
, node_possible_map
)
4135 nr_node_ids
= highest
+ 1;
4138 static inline void setup_nr_node_ids(void)
4144 * add_active_range - Register a range of PFNs backed by physical memory
4145 * @nid: The node ID the range resides on
4146 * @start_pfn: The start PFN of the available physical memory
4147 * @end_pfn: The end PFN of the available physical memory
4149 * These ranges are stored in an early_node_map[] and later used by
4150 * free_area_init_nodes() to calculate zone sizes and holes. If the
4151 * range spans a memory hole, it is up to the architecture to ensure
4152 * the memory is not freed by the bootmem allocator. If possible
4153 * the range being registered will be merged with existing ranges.
4155 void __init
add_active_range(unsigned int nid
, unsigned long start_pfn
,
4156 unsigned long end_pfn
)
4160 mminit_dprintk(MMINIT_TRACE
, "memory_register",
4161 "Entering add_active_range(%d, %#lx, %#lx) "
4162 "%d entries of %d used\n",
4163 nid
, start_pfn
, end_pfn
,
4164 nr_nodemap_entries
, MAX_ACTIVE_REGIONS
);
4166 mminit_validate_memmodel_limits(&start_pfn
, &end_pfn
);
4168 /* Merge with existing active regions if possible */
4169 for (i
= 0; i
< nr_nodemap_entries
; i
++) {
4170 if (early_node_map
[i
].nid
!= nid
)
4173 /* Skip if an existing region covers this new one */
4174 if (start_pfn
>= early_node_map
[i
].start_pfn
&&
4175 end_pfn
<= early_node_map
[i
].end_pfn
)
4178 /* Merge forward if suitable */
4179 if (start_pfn
<= early_node_map
[i
].end_pfn
&&
4180 end_pfn
> early_node_map
[i
].end_pfn
) {
4181 early_node_map
[i
].end_pfn
= end_pfn
;
4185 /* Merge backward if suitable */
4186 if (start_pfn
< early_node_map
[i
].start_pfn
&&
4187 end_pfn
>= early_node_map
[i
].start_pfn
) {
4188 early_node_map
[i
].start_pfn
= start_pfn
;
4193 /* Check that early_node_map is large enough */
4194 if (i
>= MAX_ACTIVE_REGIONS
) {
4195 printk(KERN_CRIT
"More than %d memory regions, truncating\n",
4196 MAX_ACTIVE_REGIONS
);
4200 early_node_map
[i
].nid
= nid
;
4201 early_node_map
[i
].start_pfn
= start_pfn
;
4202 early_node_map
[i
].end_pfn
= end_pfn
;
4203 nr_nodemap_entries
= i
+ 1;
4207 * remove_active_range - Shrink an existing registered range of PFNs
4208 * @nid: The node id the range is on that should be shrunk
4209 * @start_pfn: The new PFN of the range
4210 * @end_pfn: The new PFN of the range
4212 * i386 with NUMA use alloc_remap() to store a node_mem_map on a local node.
4213 * The map is kept near the end physical page range that has already been
4214 * registered. This function allows an arch to shrink an existing registered
4217 void __init
remove_active_range(unsigned int nid
, unsigned long start_pfn
,
4218 unsigned long end_pfn
)
4223 printk(KERN_DEBUG
"remove_active_range (%d, %lu, %lu)\n",
4224 nid
, start_pfn
, end_pfn
);
4226 /* Find the old active region end and shrink */
4227 for_each_active_range_index_in_nid(i
, nid
) {
4228 if (early_node_map
[i
].start_pfn
>= start_pfn
&&
4229 early_node_map
[i
].end_pfn
<= end_pfn
) {
4231 early_node_map
[i
].start_pfn
= 0;
4232 early_node_map
[i
].end_pfn
= 0;
4236 if (early_node_map
[i
].start_pfn
< start_pfn
&&
4237 early_node_map
[i
].end_pfn
> start_pfn
) {
4238 unsigned long temp_end_pfn
= early_node_map
[i
].end_pfn
;
4239 early_node_map
[i
].end_pfn
= start_pfn
;
4240 if (temp_end_pfn
> end_pfn
)
4241 add_active_range(nid
, end_pfn
, temp_end_pfn
);
4244 if (early_node_map
[i
].start_pfn
>= start_pfn
&&
4245 early_node_map
[i
].end_pfn
> end_pfn
&&
4246 early_node_map
[i
].start_pfn
< end_pfn
) {
4247 early_node_map
[i
].start_pfn
= end_pfn
;
4255 /* remove the blank ones */
4256 for (i
= nr_nodemap_entries
- 1; i
> 0; i
--) {
4257 if (early_node_map
[i
].nid
!= nid
)
4259 if (early_node_map
[i
].end_pfn
)
4261 /* we found it, get rid of it */
4262 for (j
= i
; j
< nr_nodemap_entries
- 1; j
++)
4263 memcpy(&early_node_map
[j
], &early_node_map
[j
+1],
4264 sizeof(early_node_map
[j
]));
4265 j
= nr_nodemap_entries
- 1;
4266 memset(&early_node_map
[j
], 0, sizeof(early_node_map
[j
]));
4267 nr_nodemap_entries
--;
4272 * remove_all_active_ranges - Remove all currently registered regions
4274 * During discovery, it may be found that a table like SRAT is invalid
4275 * and an alternative discovery method must be used. This function removes
4276 * all currently registered regions.
4278 void __init
remove_all_active_ranges(void)
4280 memset(early_node_map
, 0, sizeof(early_node_map
));
4281 nr_nodemap_entries
= 0;
4284 /* Compare two active node_active_regions */
4285 static int __init
cmp_node_active_region(const void *a
, const void *b
)
4287 struct node_active_region
*arange
= (struct node_active_region
*)a
;
4288 struct node_active_region
*brange
= (struct node_active_region
*)b
;
4290 /* Done this way to avoid overflows */
4291 if (arange
->start_pfn
> brange
->start_pfn
)
4293 if (arange
->start_pfn
< brange
->start_pfn
)
4299 /* sort the node_map by start_pfn */
4300 void __init
sort_node_map(void)
4302 sort(early_node_map
, (size_t)nr_nodemap_entries
,
4303 sizeof(struct node_active_region
),
4304 cmp_node_active_region
, NULL
);
4307 /* Find the lowest pfn for a node */
4308 static unsigned long __init
find_min_pfn_for_node(int nid
)
4311 unsigned long min_pfn
= ULONG_MAX
;
4313 /* Assuming a sorted map, the first range found has the starting pfn */
4314 for_each_active_range_index_in_nid(i
, nid
)
4315 min_pfn
= min(min_pfn
, early_node_map
[i
].start_pfn
);
4317 if (min_pfn
== ULONG_MAX
) {
4319 "Could not find start_pfn for node %d\n", nid
);
4327 * find_min_pfn_with_active_regions - Find the minimum PFN registered
4329 * It returns the minimum PFN based on information provided via
4330 * add_active_range().
4332 unsigned long __init
find_min_pfn_with_active_regions(void)
4334 return find_min_pfn_for_node(MAX_NUMNODES
);
4338 * early_calculate_totalpages()
4339 * Sum pages in active regions for movable zone.
4340 * Populate N_HIGH_MEMORY for calculating usable_nodes.
4342 static unsigned long __init
early_calculate_totalpages(void)
4345 unsigned long totalpages
= 0;
4347 for (i
= 0; i
< nr_nodemap_entries
; i
++) {
4348 unsigned long pages
= early_node_map
[i
].end_pfn
-
4349 early_node_map
[i
].start_pfn
;
4350 totalpages
+= pages
;
4352 node_set_state(early_node_map
[i
].nid
, N_HIGH_MEMORY
);
4358 * Find the PFN the Movable zone begins in each node. Kernel memory
4359 * is spread evenly between nodes as long as the nodes have enough
4360 * memory. When they don't, some nodes will have more kernelcore than
4363 static void __init
find_zone_movable_pfns_for_nodes(unsigned long *movable_pfn
)
4366 unsigned long usable_startpfn
;
4367 unsigned long kernelcore_node
, kernelcore_remaining
;
4368 /* save the state before borrow the nodemask */
4369 nodemask_t saved_node_state
= node_states
[N_HIGH_MEMORY
];
4370 unsigned long totalpages
= early_calculate_totalpages();
4371 int usable_nodes
= nodes_weight(node_states
[N_HIGH_MEMORY
]);
4374 * If movablecore was specified, calculate what size of
4375 * kernelcore that corresponds so that memory usable for
4376 * any allocation type is evenly spread. If both kernelcore
4377 * and movablecore are specified, then the value of kernelcore
4378 * will be used for required_kernelcore if it's greater than
4379 * what movablecore would have allowed.
4381 if (required_movablecore
) {
4382 unsigned long corepages
;
4385 * Round-up so that ZONE_MOVABLE is at least as large as what
4386 * was requested by the user
4388 required_movablecore
=
4389 roundup(required_movablecore
, MAX_ORDER_NR_PAGES
);
4390 corepages
= totalpages
- required_movablecore
;
4392 required_kernelcore
= max(required_kernelcore
, corepages
);
4395 /* If kernelcore was not specified, there is no ZONE_MOVABLE */
4396 if (!required_kernelcore
)
4399 /* usable_startpfn is the lowest possible pfn ZONE_MOVABLE can be at */
4400 find_usable_zone_for_movable();
4401 usable_startpfn
= arch_zone_lowest_possible_pfn
[movable_zone
];
4404 /* Spread kernelcore memory as evenly as possible throughout nodes */
4405 kernelcore_node
= required_kernelcore
/ usable_nodes
;
4406 for_each_node_state(nid
, N_HIGH_MEMORY
) {
4408 * Recalculate kernelcore_node if the division per node
4409 * now exceeds what is necessary to satisfy the requested
4410 * amount of memory for the kernel
4412 if (required_kernelcore
< kernelcore_node
)
4413 kernelcore_node
= required_kernelcore
/ usable_nodes
;
4416 * As the map is walked, we track how much memory is usable
4417 * by the kernel using kernelcore_remaining. When it is
4418 * 0, the rest of the node is usable by ZONE_MOVABLE
4420 kernelcore_remaining
= kernelcore_node
;
4422 /* Go through each range of PFNs within this node */
4423 for_each_active_range_index_in_nid(i
, nid
) {
4424 unsigned long start_pfn
, end_pfn
;
4425 unsigned long size_pages
;
4427 start_pfn
= max(early_node_map
[i
].start_pfn
,
4428 zone_movable_pfn
[nid
]);
4429 end_pfn
= early_node_map
[i
].end_pfn
;
4430 if (start_pfn
>= end_pfn
)
4433 /* Account for what is only usable for kernelcore */
4434 if (start_pfn
< usable_startpfn
) {
4435 unsigned long kernel_pages
;
4436 kernel_pages
= min(end_pfn
, usable_startpfn
)
4439 kernelcore_remaining
-= min(kernel_pages
,
4440 kernelcore_remaining
);
4441 required_kernelcore
-= min(kernel_pages
,
4442 required_kernelcore
);
4444 /* Continue if range is now fully accounted */
4445 if (end_pfn
<= usable_startpfn
) {
4448 * Push zone_movable_pfn to the end so
4449 * that if we have to rebalance
4450 * kernelcore across nodes, we will
4451 * not double account here
4453 zone_movable_pfn
[nid
] = end_pfn
;
4456 start_pfn
= usable_startpfn
;
4460 * The usable PFN range for ZONE_MOVABLE is from
4461 * start_pfn->end_pfn. Calculate size_pages as the
4462 * number of pages used as kernelcore
4464 size_pages
= end_pfn
- start_pfn
;
4465 if (size_pages
> kernelcore_remaining
)
4466 size_pages
= kernelcore_remaining
;
4467 zone_movable_pfn
[nid
] = start_pfn
+ size_pages
;
4470 * Some kernelcore has been met, update counts and
4471 * break if the kernelcore for this node has been
4474 required_kernelcore
-= min(required_kernelcore
,
4476 kernelcore_remaining
-= size_pages
;
4477 if (!kernelcore_remaining
)
4483 * If there is still required_kernelcore, we do another pass with one
4484 * less node in the count. This will push zone_movable_pfn[nid] further
4485 * along on the nodes that still have memory until kernelcore is
4489 if (usable_nodes
&& required_kernelcore
> usable_nodes
)
4492 /* Align start of ZONE_MOVABLE on all nids to MAX_ORDER_NR_PAGES */
4493 for (nid
= 0; nid
< MAX_NUMNODES
; nid
++)
4494 zone_movable_pfn
[nid
] =
4495 roundup(zone_movable_pfn
[nid
], MAX_ORDER_NR_PAGES
);
4498 /* restore the node_state */
4499 node_states
[N_HIGH_MEMORY
] = saved_node_state
;
4502 /* Any regular memory on that node ? */
4503 static void check_for_regular_memory(pg_data_t
*pgdat
)
4505 #ifdef CONFIG_HIGHMEM
4506 enum zone_type zone_type
;
4508 for (zone_type
= 0; zone_type
<= ZONE_NORMAL
; zone_type
++) {
4509 struct zone
*zone
= &pgdat
->node_zones
[zone_type
];
4510 if (zone
->present_pages
)
4511 node_set_state(zone_to_nid(zone
), N_NORMAL_MEMORY
);
4517 * free_area_init_nodes - Initialise all pg_data_t and zone data
4518 * @max_zone_pfn: an array of max PFNs for each zone
4520 * This will call free_area_init_node() for each active node in the system.
4521 * Using the page ranges provided by add_active_range(), the size of each
4522 * zone in each node and their holes is calculated. If the maximum PFN
4523 * between two adjacent zones match, it is assumed that the zone is empty.
4524 * For example, if arch_max_dma_pfn == arch_max_dma32_pfn, it is assumed
4525 * that arch_max_dma32_pfn has no pages. It is also assumed that a zone
4526 * starts where the previous one ended. For example, ZONE_DMA32 starts
4527 * at arch_max_dma_pfn.
4529 void __init
free_area_init_nodes(unsigned long *max_zone_pfn
)
4534 /* Sort early_node_map as initialisation assumes it is sorted */
4537 /* Record where the zone boundaries are */
4538 memset(arch_zone_lowest_possible_pfn
, 0,
4539 sizeof(arch_zone_lowest_possible_pfn
));
4540 memset(arch_zone_highest_possible_pfn
, 0,
4541 sizeof(arch_zone_highest_possible_pfn
));
4542 arch_zone_lowest_possible_pfn
[0] = find_min_pfn_with_active_regions();
4543 arch_zone_highest_possible_pfn
[0] = max_zone_pfn
[0];
4544 for (i
= 1; i
< MAX_NR_ZONES
; i
++) {
4545 if (i
== ZONE_MOVABLE
)
4547 arch_zone_lowest_possible_pfn
[i
] =
4548 arch_zone_highest_possible_pfn
[i
-1];
4549 arch_zone_highest_possible_pfn
[i
] =
4550 max(max_zone_pfn
[i
], arch_zone_lowest_possible_pfn
[i
]);
4552 arch_zone_lowest_possible_pfn
[ZONE_MOVABLE
] = 0;
4553 arch_zone_highest_possible_pfn
[ZONE_MOVABLE
] = 0;
4555 /* Find the PFNs that ZONE_MOVABLE begins at in each node */
4556 memset(zone_movable_pfn
, 0, sizeof(zone_movable_pfn
));
4557 find_zone_movable_pfns_for_nodes(zone_movable_pfn
);
4559 /* Print out the zone ranges */
4560 printk("Zone PFN ranges:\n");
4561 for (i
= 0; i
< MAX_NR_ZONES
; i
++) {
4562 if (i
== ZONE_MOVABLE
)
4564 printk(" %-8s ", zone_names
[i
]);
4565 if (arch_zone_lowest_possible_pfn
[i
] ==
4566 arch_zone_highest_possible_pfn
[i
])
4569 printk("%0#10lx -> %0#10lx\n",
4570 arch_zone_lowest_possible_pfn
[i
],
4571 arch_zone_highest_possible_pfn
[i
]);
4574 /* Print out the PFNs ZONE_MOVABLE begins at in each node */
4575 printk("Movable zone start PFN for each node\n");
4576 for (i
= 0; i
< MAX_NUMNODES
; i
++) {
4577 if (zone_movable_pfn
[i
])
4578 printk(" Node %d: %lu\n", i
, zone_movable_pfn
[i
]);
4581 /* Print out the early_node_map[] */
4582 printk("early_node_map[%d] active PFN ranges\n", nr_nodemap_entries
);
4583 for (i
= 0; i
< nr_nodemap_entries
; i
++)
4584 printk(" %3d: %0#10lx -> %0#10lx\n", early_node_map
[i
].nid
,
4585 early_node_map
[i
].start_pfn
,
4586 early_node_map
[i
].end_pfn
);
4588 /* Initialise every node */
4589 mminit_verify_pageflags_layout();
4590 setup_nr_node_ids();
4591 for_each_online_node(nid
) {
4592 pg_data_t
*pgdat
= NODE_DATA(nid
);
4593 free_area_init_node(nid
, NULL
,
4594 find_min_pfn_for_node(nid
), NULL
);
4596 /* Any memory on that node */
4597 if (pgdat
->node_present_pages
)
4598 node_set_state(nid
, N_HIGH_MEMORY
);
4599 check_for_regular_memory(pgdat
);
4603 static int __init
cmdline_parse_core(char *p
, unsigned long *core
)
4605 unsigned long long coremem
;
4609 coremem
= memparse(p
, &p
);
4610 *core
= coremem
>> PAGE_SHIFT
;
4612 /* Paranoid check that UL is enough for the coremem value */
4613 WARN_ON((coremem
>> PAGE_SHIFT
) > ULONG_MAX
);
4619 * kernelcore=size sets the amount of memory for use for allocations that
4620 * cannot be reclaimed or migrated.
4622 static int __init
cmdline_parse_kernelcore(char *p
)
4624 return cmdline_parse_core(p
, &required_kernelcore
);
4628 * movablecore=size sets the amount of memory for use for allocations that
4629 * can be reclaimed or migrated.
4631 static int __init
cmdline_parse_movablecore(char *p
)
4633 return cmdline_parse_core(p
, &required_movablecore
);
4636 early_param("kernelcore", cmdline_parse_kernelcore
);
4637 early_param("movablecore", cmdline_parse_movablecore
);
4639 #endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
4642 * set_dma_reserve - set the specified number of pages reserved in the first zone
4643 * @new_dma_reserve: The number of pages to mark reserved
4645 * The per-cpu batchsize and zone watermarks are determined by present_pages.
4646 * In the DMA zone, a significant percentage may be consumed by kernel image
4647 * and other unfreeable allocations which can skew the watermarks badly. This
4648 * function may optionally be used to account for unfreeable pages in the
4649 * first zone (e.g., ZONE_DMA). The effect will be lower watermarks and
4650 * smaller per-cpu batchsize.
4652 void __init
set_dma_reserve(unsigned long new_dma_reserve
)
4654 dma_reserve
= new_dma_reserve
;
4657 #ifndef CONFIG_NEED_MULTIPLE_NODES
4658 struct pglist_data __refdata contig_page_data
= {
4659 #ifndef CONFIG_NO_BOOTMEM
4660 .bdata
= &bootmem_node_data
[0]
4663 EXPORT_SYMBOL(contig_page_data
);
4666 void __init
free_area_init(unsigned long *zones_size
)
4668 free_area_init_node(0, zones_size
,
4669 __pa(PAGE_OFFSET
) >> PAGE_SHIFT
, NULL
);
4672 static int page_alloc_cpu_notify(struct notifier_block
*self
,
4673 unsigned long action
, void *hcpu
)
4675 int cpu
= (unsigned long)hcpu
;
4677 if (action
== CPU_DEAD
|| action
== CPU_DEAD_FROZEN
) {
4681 * Spill the event counters of the dead processor
4682 * into the current processors event counters.
4683 * This artificially elevates the count of the current
4686 vm_events_fold_cpu(cpu
);
4689 * Zero the differential counters of the dead processor
4690 * so that the vm statistics are consistent.
4692 * This is only okay since the processor is dead and cannot
4693 * race with what we are doing.
4695 refresh_cpu_vm_stats(cpu
);
4700 void __init
page_alloc_init(void)
4702 hotcpu_notifier(page_alloc_cpu_notify
, 0);
4706 * calculate_totalreserve_pages - called when sysctl_lower_zone_reserve_ratio
4707 * or min_free_kbytes changes.
4709 static void calculate_totalreserve_pages(void)
4711 struct pglist_data
*pgdat
;
4712 unsigned long reserve_pages
= 0;
4713 enum zone_type i
, j
;
4715 for_each_online_pgdat(pgdat
) {
4716 for (i
= 0; i
< MAX_NR_ZONES
; i
++) {
4717 struct zone
*zone
= pgdat
->node_zones
+ i
;
4718 unsigned long max
= 0;
4720 /* Find valid and maximum lowmem_reserve in the zone */
4721 for (j
= i
; j
< MAX_NR_ZONES
; j
++) {
4722 if (zone
->lowmem_reserve
[j
] > max
)
4723 max
= zone
->lowmem_reserve
[j
];
4726 /* we treat the high watermark as reserved pages. */
4727 max
+= high_wmark_pages(zone
);
4729 if (max
> zone
->present_pages
)
4730 max
= zone
->present_pages
;
4731 reserve_pages
+= max
;
4734 totalreserve_pages
= reserve_pages
;
4738 * setup_per_zone_lowmem_reserve - called whenever
4739 * sysctl_lower_zone_reserve_ratio changes. Ensures that each zone
4740 * has a correct pages reserved value, so an adequate number of
4741 * pages are left in the zone after a successful __alloc_pages().
4743 static void setup_per_zone_lowmem_reserve(void)
4745 struct pglist_data
*pgdat
;
4746 enum zone_type j
, idx
;
4748 for_each_online_pgdat(pgdat
) {
4749 for (j
= 0; j
< MAX_NR_ZONES
; j
++) {
4750 struct zone
*zone
= pgdat
->node_zones
+ j
;
4751 unsigned long present_pages
= zone
->present_pages
;
4753 zone
->lowmem_reserve
[j
] = 0;
4757 struct zone
*lower_zone
;
4761 if (sysctl_lowmem_reserve_ratio
[idx
] < 1)
4762 sysctl_lowmem_reserve_ratio
[idx
] = 1;
4764 lower_zone
= pgdat
->node_zones
+ idx
;
4765 lower_zone
->lowmem_reserve
[j
] = present_pages
/
4766 sysctl_lowmem_reserve_ratio
[idx
];
4767 present_pages
+= lower_zone
->present_pages
;
4772 /* update totalreserve_pages */
4773 calculate_totalreserve_pages();
4777 * setup_per_zone_wmarks - called when min_free_kbytes changes
4778 * or when memory is hot-{added|removed}
4780 * Ensures that the watermark[min,low,high] values for each zone are set
4781 * correctly with respect to min_free_kbytes.
4783 void setup_per_zone_wmarks(void)
4785 unsigned long pages_min
= min_free_kbytes
>> (PAGE_SHIFT
- 10);
4786 unsigned long lowmem_pages
= 0;
4788 unsigned long flags
;
4790 /* Calculate total number of !ZONE_HIGHMEM pages */
4791 for_each_zone(zone
) {
4792 if (!is_highmem(zone
))
4793 lowmem_pages
+= zone
->present_pages
;
4796 for_each_zone(zone
) {
4799 spin_lock_irqsave(&zone
->lock
, flags
);
4800 tmp
= (u64
)pages_min
* zone
->present_pages
;
4801 do_div(tmp
, lowmem_pages
);
4802 if (is_highmem(zone
)) {
4804 * __GFP_HIGH and PF_MEMALLOC allocations usually don't
4805 * need highmem pages, so cap pages_min to a small
4808 * The WMARK_HIGH-WMARK_LOW and (WMARK_LOW-WMARK_MIN)
4809 * deltas controls asynch page reclaim, and so should
4810 * not be capped for highmem.
4814 min_pages
= zone
->present_pages
/ 1024;
4815 if (min_pages
< SWAP_CLUSTER_MAX
)
4816 min_pages
= SWAP_CLUSTER_MAX
;
4817 if (min_pages
> 128)
4819 zone
->watermark
[WMARK_MIN
] = min_pages
;
4822 * If it's a lowmem zone, reserve a number of pages
4823 * proportionate to the zone's size.
4825 zone
->watermark
[WMARK_MIN
] = tmp
;
4828 zone
->watermark
[WMARK_LOW
] = min_wmark_pages(zone
) + (tmp
>> 2);
4829 zone
->watermark
[WMARK_HIGH
] = min_wmark_pages(zone
) + (tmp
>> 1);
4830 setup_zone_migrate_reserve(zone
);
4831 spin_unlock_irqrestore(&zone
->lock
, flags
);
4834 /* update totalreserve_pages */
4835 calculate_totalreserve_pages();
4839 * The inactive anon list should be small enough that the VM never has to
4840 * do too much work, but large enough that each inactive page has a chance
4841 * to be referenced again before it is swapped out.
4843 * The inactive_anon ratio is the target ratio of ACTIVE_ANON to
4844 * INACTIVE_ANON pages on this zone's LRU, maintained by the
4845 * pageout code. A zone->inactive_ratio of 3 means 3:1 or 25% of
4846 * the anonymous pages are kept on the inactive list.
4849 * memory ratio inactive anon
4850 * -------------------------------------
4859 void calculate_zone_inactive_ratio(struct zone
*zone
)
4861 unsigned int gb
, ratio
;
4863 /* Zone size in gigabytes */
4864 gb
= zone
->present_pages
>> (30 - PAGE_SHIFT
);
4866 ratio
= int_sqrt(10 * gb
);
4870 zone
->inactive_ratio
= ratio
;
4873 static void __init
setup_per_zone_inactive_ratio(void)
4878 calculate_zone_inactive_ratio(zone
);
4882 * Initialise min_free_kbytes.
4884 * For small machines we want it small (128k min). For large machines
4885 * we want it large (64MB max). But it is not linear, because network
4886 * bandwidth does not increase linearly with machine size. We use
4888 * min_free_kbytes = 4 * sqrt(lowmem_kbytes), for better accuracy:
4889 * min_free_kbytes = sqrt(lowmem_kbytes * 16)
4905 static int __init
init_per_zone_wmark_min(void)
4907 unsigned long lowmem_kbytes
;
4909 lowmem_kbytes
= nr_free_buffer_pages() * (PAGE_SIZE
>> 10);
4911 min_free_kbytes
= int_sqrt(lowmem_kbytes
* 16);
4912 if (min_free_kbytes
< 128)
4913 min_free_kbytes
= 128;
4914 if (min_free_kbytes
> 65536)
4915 min_free_kbytes
= 65536;
4916 setup_per_zone_wmarks();
4917 setup_per_zone_lowmem_reserve();
4918 setup_per_zone_inactive_ratio();
4921 module_init(init_per_zone_wmark_min
)
4924 * min_free_kbytes_sysctl_handler - just a wrapper around proc_dointvec() so
4925 * that we can call two helper functions whenever min_free_kbytes
4928 int min_free_kbytes_sysctl_handler(ctl_table
*table
, int write
,
4929 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
4931 proc_dointvec(table
, write
, buffer
, length
, ppos
);
4933 setup_per_zone_wmarks();
4938 int sysctl_min_unmapped_ratio_sysctl_handler(ctl_table
*table
, int write
,
4939 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
4944 rc
= proc_dointvec_minmax(table
, write
, buffer
, length
, ppos
);
4949 zone
->min_unmapped_pages
= (zone
->present_pages
*
4950 sysctl_min_unmapped_ratio
) / 100;
4954 int sysctl_min_slab_ratio_sysctl_handler(ctl_table
*table
, int write
,
4955 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
4960 rc
= proc_dointvec_minmax(table
, write
, buffer
, length
, ppos
);
4965 zone
->min_slab_pages
= (zone
->present_pages
*
4966 sysctl_min_slab_ratio
) / 100;
4972 * lowmem_reserve_ratio_sysctl_handler - just a wrapper around
4973 * proc_dointvec() so that we can call setup_per_zone_lowmem_reserve()
4974 * whenever sysctl_lowmem_reserve_ratio changes.
4976 * The reserve ratio obviously has absolutely no relation with the
4977 * minimum watermarks. The lowmem reserve ratio can only make sense
4978 * if in function of the boot time zone sizes.
4980 int lowmem_reserve_ratio_sysctl_handler(ctl_table
*table
, int write
,
4981 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
4983 proc_dointvec_minmax(table
, write
, buffer
, length
, ppos
);
4984 setup_per_zone_lowmem_reserve();
4989 * percpu_pagelist_fraction - changes the pcp->high for each zone on each
4990 * cpu. It is the fraction of total pages in each zone that a hot per cpu pagelist
4991 * can have before it gets flushed back to buddy allocator.
4994 int percpu_pagelist_fraction_sysctl_handler(ctl_table
*table
, int write
,
4995 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
5001 ret
= proc_dointvec_minmax(table
, write
, buffer
, length
, ppos
);
5002 if (!write
|| (ret
== -EINVAL
))
5004 for_each_populated_zone(zone
) {
5005 for_each_possible_cpu(cpu
) {
5007 high
= zone
->present_pages
/ percpu_pagelist_fraction
;
5008 setup_pagelist_highmark(
5009 per_cpu_ptr(zone
->pageset
, cpu
), high
);
5015 int hashdist
= HASHDIST_DEFAULT
;
5018 static int __init
set_hashdist(char *str
)
5022 hashdist
= simple_strtoul(str
, &str
, 0);
5025 __setup("hashdist=", set_hashdist
);
5029 * allocate a large system hash table from bootmem
5030 * - it is assumed that the hash table must contain an exact power-of-2
5031 * quantity of entries
5032 * - limit is the number of hash buckets, not the total allocation size
5034 void *__init
alloc_large_system_hash(const char *tablename
,
5035 unsigned long bucketsize
,
5036 unsigned long numentries
,
5039 unsigned int *_hash_shift
,
5040 unsigned int *_hash_mask
,
5041 unsigned long limit
)
5043 unsigned long long max
= limit
;
5044 unsigned long log2qty
, size
;
5047 /* allow the kernel cmdline to have a say */
5049 /* round applicable memory size up to nearest megabyte */
5050 numentries
= nr_kernel_pages
;
5051 numentries
+= (1UL << (20 - PAGE_SHIFT
)) - 1;
5052 numentries
>>= 20 - PAGE_SHIFT
;
5053 numentries
<<= 20 - PAGE_SHIFT
;
5055 /* limit to 1 bucket per 2^scale bytes of low memory */
5056 if (scale
> PAGE_SHIFT
)
5057 numentries
>>= (scale
- PAGE_SHIFT
);
5059 numentries
<<= (PAGE_SHIFT
- scale
);
5061 /* Make sure we've got at least a 0-order allocation.. */
5062 if (unlikely(flags
& HASH_SMALL
)) {
5063 /* Makes no sense without HASH_EARLY */
5064 WARN_ON(!(flags
& HASH_EARLY
));
5065 if (!(numentries
>> *_hash_shift
)) {
5066 numentries
= 1UL << *_hash_shift
;
5067 BUG_ON(!numentries
);
5069 } else if (unlikely((numentries
* bucketsize
) < PAGE_SIZE
))
5070 numentries
= PAGE_SIZE
/ bucketsize
;
5072 numentries
= roundup_pow_of_two(numentries
);
5074 /* limit allocation size to 1/16 total memory by default */
5076 max
= ((unsigned long long)nr_all_pages
<< PAGE_SHIFT
) >> 4;
5077 do_div(max
, bucketsize
);
5080 if (numentries
> max
)
5083 log2qty
= ilog2(numentries
);
5086 size
= bucketsize
<< log2qty
;
5087 if (flags
& HASH_EARLY
)
5088 table
= alloc_bootmem_nopanic(size
);
5090 table
= __vmalloc(size
, GFP_ATOMIC
, PAGE_KERNEL
);
5093 * If bucketsize is not a power-of-two, we may free
5094 * some pages at the end of hash table which
5095 * alloc_pages_exact() automatically does
5097 if (get_order(size
) < MAX_ORDER
) {
5098 table
= alloc_pages_exact(size
, GFP_ATOMIC
);
5099 kmemleak_alloc(table
, size
, 1, GFP_ATOMIC
);
5102 } while (!table
&& size
> PAGE_SIZE
&& --log2qty
);
5105 panic("Failed to allocate %s hash table\n", tablename
);
5107 printk(KERN_INFO
"%s hash table entries: %d (order: %d, %lu bytes)\n",
5110 ilog2(size
) - PAGE_SHIFT
,
5114 *_hash_shift
= log2qty
;
5116 *_hash_mask
= (1 << log2qty
) - 1;
5121 /* Return a pointer to the bitmap storing bits affecting a block of pages */
5122 static inline unsigned long *get_pageblock_bitmap(struct zone
*zone
,
5125 #ifdef CONFIG_SPARSEMEM
5126 return __pfn_to_section(pfn
)->pageblock_flags
;
5128 return zone
->pageblock_flags
;
5129 #endif /* CONFIG_SPARSEMEM */
5132 static inline int pfn_to_bitidx(struct zone
*zone
, unsigned long pfn
)
5134 #ifdef CONFIG_SPARSEMEM
5135 pfn
&= (PAGES_PER_SECTION
-1);
5136 return (pfn
>> pageblock_order
) * NR_PAGEBLOCK_BITS
;
5138 pfn
= pfn
- zone
->zone_start_pfn
;
5139 return (pfn
>> pageblock_order
) * NR_PAGEBLOCK_BITS
;
5140 #endif /* CONFIG_SPARSEMEM */
5144 * get_pageblock_flags_group - Return the requested group of flags for the pageblock_nr_pages block of pages
5145 * @page: The page within the block of interest
5146 * @start_bitidx: The first bit of interest to retrieve
5147 * @end_bitidx: The last bit of interest
5148 * returns pageblock_bits flags
5150 unsigned long get_pageblock_flags_group(struct page
*page
,
5151 int start_bitidx
, int end_bitidx
)
5154 unsigned long *bitmap
;
5155 unsigned long pfn
, bitidx
;
5156 unsigned long flags
= 0;
5157 unsigned long value
= 1;
5159 zone
= page_zone(page
);
5160 pfn
= page_to_pfn(page
);
5161 bitmap
= get_pageblock_bitmap(zone
, pfn
);
5162 bitidx
= pfn_to_bitidx(zone
, pfn
);
5164 for (; start_bitidx
<= end_bitidx
; start_bitidx
++, value
<<= 1)
5165 if (test_bit(bitidx
+ start_bitidx
, bitmap
))
5172 * set_pageblock_flags_group - Set the requested group of flags for a pageblock_nr_pages block of pages
5173 * @page: The page within the block of interest
5174 * @start_bitidx: The first bit of interest
5175 * @end_bitidx: The last bit of interest
5176 * @flags: The flags to set
5178 void set_pageblock_flags_group(struct page
*page
, unsigned long flags
,
5179 int start_bitidx
, int end_bitidx
)
5182 unsigned long *bitmap
;
5183 unsigned long pfn
, bitidx
;
5184 unsigned long value
= 1;
5186 zone
= page_zone(page
);
5187 pfn
= page_to_pfn(page
);
5188 bitmap
= get_pageblock_bitmap(zone
, pfn
);
5189 bitidx
= pfn_to_bitidx(zone
, pfn
);
5190 VM_BUG_ON(pfn
< zone
->zone_start_pfn
);
5191 VM_BUG_ON(pfn
>= zone
->zone_start_pfn
+ zone
->spanned_pages
);
5193 for (; start_bitidx
<= end_bitidx
; start_bitidx
++, value
<<= 1)
5195 __set_bit(bitidx
+ start_bitidx
, bitmap
);
5197 __clear_bit(bitidx
+ start_bitidx
, bitmap
);
5201 * This is designed as sub function...plz see page_isolation.c also.
5202 * set/clear page block's type to be ISOLATE.
5203 * page allocater never alloc memory from ISOLATE block.
5206 int set_migratetype_isolate(struct page
*page
)
5209 struct page
*curr_page
;
5210 unsigned long flags
, pfn
, iter
;
5211 unsigned long immobile
= 0;
5212 struct memory_isolate_notify arg
;
5217 zone
= page_zone(page
);
5218 zone_idx
= zone_idx(zone
);
5220 spin_lock_irqsave(&zone
->lock
, flags
);
5221 if (get_pageblock_migratetype(page
) == MIGRATE_MOVABLE
||
5222 zone_idx
== ZONE_MOVABLE
) {
5227 pfn
= page_to_pfn(page
);
5228 arg
.start_pfn
= pfn
;
5229 arg
.nr_pages
= pageblock_nr_pages
;
5230 arg
.pages_found
= 0;
5233 * It may be possible to isolate a pageblock even if the
5234 * migratetype is not MIGRATE_MOVABLE. The memory isolation
5235 * notifier chain is used by balloon drivers to return the
5236 * number of pages in a range that are held by the balloon
5237 * driver to shrink memory. If all the pages are accounted for
5238 * by balloons, are free, or on the LRU, isolation can continue.
5239 * Later, for example, when memory hotplug notifier runs, these
5240 * pages reported as "can be isolated" should be isolated(freed)
5241 * by the balloon driver through the memory notifier chain.
5243 notifier_ret
= memory_isolate_notify(MEM_ISOLATE_COUNT
, &arg
);
5244 notifier_ret
= notifier_to_errno(notifier_ret
);
5245 if (notifier_ret
|| !arg
.pages_found
)
5248 for (iter
= pfn
; iter
< (pfn
+ pageblock_nr_pages
); iter
++) {
5249 if (!pfn_valid_within(pfn
))
5252 curr_page
= pfn_to_page(iter
);
5253 if (!page_count(curr_page
) || PageLRU(curr_page
))
5259 if (arg
.pages_found
== immobile
)
5264 set_pageblock_migratetype(page
, MIGRATE_ISOLATE
);
5265 move_freepages_block(zone
, page
, MIGRATE_ISOLATE
);
5268 spin_unlock_irqrestore(&zone
->lock
, flags
);
5274 void unset_migratetype_isolate(struct page
*page
)
5277 unsigned long flags
;
5278 zone
= page_zone(page
);
5279 spin_lock_irqsave(&zone
->lock
, flags
);
5280 if (get_pageblock_migratetype(page
) != MIGRATE_ISOLATE
)
5282 set_pageblock_migratetype(page
, MIGRATE_MOVABLE
);
5283 move_freepages_block(zone
, page
, MIGRATE_MOVABLE
);
5285 spin_unlock_irqrestore(&zone
->lock
, flags
);
5288 #ifdef CONFIG_MEMORY_HOTREMOVE
5290 * All pages in the range must be isolated before calling this.
5293 __offline_isolated_pages(unsigned long start_pfn
, unsigned long end_pfn
)
5299 unsigned long flags
;
5300 /* find the first valid pfn */
5301 for (pfn
= start_pfn
; pfn
< end_pfn
; pfn
++)
5306 zone
= page_zone(pfn_to_page(pfn
));
5307 spin_lock_irqsave(&zone
->lock
, flags
);
5309 while (pfn
< end_pfn
) {
5310 if (!pfn_valid(pfn
)) {
5314 page
= pfn_to_page(pfn
);
5315 BUG_ON(page_count(page
));
5316 BUG_ON(!PageBuddy(page
));
5317 order
= page_order(page
);
5318 #ifdef CONFIG_DEBUG_VM
5319 printk(KERN_INFO
"remove from free list %lx %d %lx\n",
5320 pfn
, 1 << order
, end_pfn
);
5322 list_del(&page
->lru
);
5323 rmv_page_order(page
);
5324 zone
->free_area
[order
].nr_free
--;
5325 __mod_zone_page_state(zone
, NR_FREE_PAGES
,
5327 for (i
= 0; i
< (1 << order
); i
++)
5328 SetPageReserved((page
+i
));
5329 pfn
+= (1 << order
);
5331 spin_unlock_irqrestore(&zone
->lock
, flags
);
5335 #ifdef CONFIG_MEMORY_FAILURE
5336 bool is_free_buddy_page(struct page
*page
)
5338 struct zone
*zone
= page_zone(page
);
5339 unsigned long pfn
= page_to_pfn(page
);
5340 unsigned long flags
;
5343 spin_lock_irqsave(&zone
->lock
, flags
);
5344 for (order
= 0; order
< MAX_ORDER
; order
++) {
5345 struct page
*page_head
= page
- (pfn
& ((1 << order
) - 1));
5347 if (PageBuddy(page_head
) && page_order(page_head
) >= order
)
5350 spin_unlock_irqrestore(&zone
->lock
, flags
);
5352 return order
< MAX_ORDER
;
5356 static struct trace_print_flags pageflag_names
[] = {
5357 {1UL << PG_locked
, "locked" },
5358 {1UL << PG_error
, "error" },
5359 {1UL << PG_referenced
, "referenced" },
5360 {1UL << PG_uptodate
, "uptodate" },
5361 {1UL << PG_dirty
, "dirty" },
5362 {1UL << PG_lru
, "lru" },
5363 {1UL << PG_active
, "active" },
5364 {1UL << PG_slab
, "slab" },
5365 {1UL << PG_owner_priv_1
, "owner_priv_1" },
5366 {1UL << PG_arch_1
, "arch_1" },
5367 {1UL << PG_reserved
, "reserved" },
5368 {1UL << PG_private
, "private" },
5369 {1UL << PG_private_2
, "private_2" },
5370 {1UL << PG_writeback
, "writeback" },
5371 #ifdef CONFIG_PAGEFLAGS_EXTENDED
5372 {1UL << PG_head
, "head" },
5373 {1UL << PG_tail
, "tail" },
5375 {1UL << PG_compound
, "compound" },
5377 {1UL << PG_swapcache
, "swapcache" },
5378 {1UL << PG_mappedtodisk
, "mappedtodisk" },
5379 {1UL << PG_reclaim
, "reclaim" },
5380 {1UL << PG_buddy
, "buddy" },
5381 {1UL << PG_swapbacked
, "swapbacked" },
5382 {1UL << PG_unevictable
, "unevictable" },
5384 {1UL << PG_mlocked
, "mlocked" },
5386 #ifdef CONFIG_ARCH_USES_PG_UNCACHED
5387 {1UL << PG_uncached
, "uncached" },
5389 #ifdef CONFIG_MEMORY_FAILURE
5390 {1UL << PG_hwpoison
, "hwpoison" },
5395 static void dump_page_flags(unsigned long flags
)
5397 const char *delim
= "";
5401 printk(KERN_ALERT
"page flags: %#lx(", flags
);
5403 /* remove zone id */
5404 flags
&= (1UL << NR_PAGEFLAGS
) - 1;
5406 for (i
= 0; pageflag_names
[i
].name
&& flags
; i
++) {
5408 mask
= pageflag_names
[i
].mask
;
5409 if ((flags
& mask
) != mask
)
5413 printk("%s%s", delim
, pageflag_names
[i
].name
);
5417 /* check for left over flags */
5419 printk("%s%#lx", delim
, flags
);
5424 void dump_page(struct page
*page
)
5427 "page:%p count:%d mapcount:%d mapping:%p index:%#lx\n",
5428 page
, page_count(page
), page_mapcount(page
),
5429 page
->mapping
, page
->index
);
5430 dump_page_flags(page
->flags
);