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/bootmem.h>
23 #include <linux/compiler.h>
24 #include <linux/kernel.h>
25 #include <linux/module.h>
26 #include <linux/suspend.h>
27 #include <linux/pagevec.h>
28 #include <linux/blkdev.h>
29 #include <linux/slab.h>
30 #include <linux/notifier.h>
31 #include <linux/topology.h>
32 #include <linux/sysctl.h>
33 #include <linux/cpu.h>
34 #include <linux/cpuset.h>
35 #include <linux/memory_hotplug.h>
36 #include <linux/nodemask.h>
37 #include <linux/vmalloc.h>
38 #include <linux/mempolicy.h>
39 #include <linux/stop_machine.h>
40 #include <linux/sort.h>
41 #include <linux/pfn.h>
42 #include <linux/backing-dev.h>
43 #include <linux/fault-inject.h>
45 #include <asm/tlbflush.h>
46 #include <asm/div64.h>
50 * Array of node states.
52 nodemask_t node_states
[NR_NODE_STATES
] __read_mostly
= {
53 [N_POSSIBLE
] = NODE_MASK_ALL
,
54 [N_ONLINE
] = { { [0] = 1UL } },
56 [N_NORMAL_MEMORY
] = { { [0] = 1UL } },
58 [N_HIGH_MEMORY
] = { { [0] = 1UL } },
60 [N_CPU
] = { { [0] = 1UL } },
63 EXPORT_SYMBOL(node_states
);
65 unsigned long totalram_pages __read_mostly
;
66 unsigned long totalreserve_pages __read_mostly
;
68 int percpu_pagelist_fraction
;
70 static void __free_pages_ok(struct page
*page
, unsigned int order
);
73 * results with 256, 32 in the lowmem_reserve sysctl:
74 * 1G machine -> (16M dma, 800M-16M normal, 1G-800M high)
75 * 1G machine -> (16M dma, 784M normal, 224M high)
76 * NORMAL allocation will leave 784M/256 of ram reserved in the ZONE_DMA
77 * HIGHMEM allocation will leave 224M/32 of ram reserved in ZONE_NORMAL
78 * HIGHMEM allocation will (224M+784M)/256 of ram reserved in ZONE_DMA
80 * TBD: should special case ZONE_DMA32 machines here - in those we normally
81 * don't need any ZONE_NORMAL reservation
83 int sysctl_lowmem_reserve_ratio
[MAX_NR_ZONES
-1] = {
84 #ifdef CONFIG_ZONE_DMA
87 #ifdef CONFIG_ZONE_DMA32
96 EXPORT_SYMBOL(totalram_pages
);
98 static char * const zone_names
[MAX_NR_ZONES
] = {
99 #ifdef CONFIG_ZONE_DMA
102 #ifdef CONFIG_ZONE_DMA32
106 #ifdef CONFIG_HIGHMEM
112 int min_free_kbytes
= 1024;
114 unsigned long __meminitdata nr_kernel_pages
;
115 unsigned long __meminitdata nr_all_pages
;
116 static unsigned long __meminitdata dma_reserve
;
118 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
120 * MAX_ACTIVE_REGIONS determines the maxmimum number of distinct
121 * ranges of memory (RAM) that may be registered with add_active_range().
122 * Ranges passed to add_active_range() will be merged if possible
123 * so the number of times add_active_range() can be called is
124 * related to the number of nodes and the number of holes
126 #ifdef CONFIG_MAX_ACTIVE_REGIONS
127 /* Allow an architecture to set MAX_ACTIVE_REGIONS to save memory */
128 #define MAX_ACTIVE_REGIONS CONFIG_MAX_ACTIVE_REGIONS
130 #if MAX_NUMNODES >= 32
131 /* If there can be many nodes, allow up to 50 holes per node */
132 #define MAX_ACTIVE_REGIONS (MAX_NUMNODES*50)
134 /* By default, allow up to 256 distinct regions */
135 #define MAX_ACTIVE_REGIONS 256
139 static struct node_active_region __meminitdata early_node_map
[MAX_ACTIVE_REGIONS
];
140 static int __meminitdata nr_nodemap_entries
;
141 static unsigned long __meminitdata arch_zone_lowest_possible_pfn
[MAX_NR_ZONES
];
142 static unsigned long __meminitdata arch_zone_highest_possible_pfn
[MAX_NR_ZONES
];
143 #ifdef CONFIG_MEMORY_HOTPLUG_RESERVE
144 static unsigned long __meminitdata node_boundary_start_pfn
[MAX_NUMNODES
];
145 static unsigned long __meminitdata node_boundary_end_pfn
[MAX_NUMNODES
];
146 #endif /* CONFIG_MEMORY_HOTPLUG_RESERVE */
147 unsigned long __initdata required_kernelcore
;
148 unsigned long __initdata required_movablecore
;
149 unsigned long __meminitdata zone_movable_pfn
[MAX_NUMNODES
];
151 /* movable_zone is the "real" zone pages in ZONE_MOVABLE are taken from */
153 EXPORT_SYMBOL(movable_zone
);
154 #endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
157 int nr_node_ids __read_mostly
= MAX_NUMNODES
;
158 EXPORT_SYMBOL(nr_node_ids
);
161 #ifdef CONFIG_DEBUG_VM
162 static int page_outside_zone_boundaries(struct zone
*zone
, struct page
*page
)
166 unsigned long pfn
= page_to_pfn(page
);
169 seq
= zone_span_seqbegin(zone
);
170 if (pfn
>= zone
->zone_start_pfn
+ zone
->spanned_pages
)
172 else if (pfn
< zone
->zone_start_pfn
)
174 } while (zone_span_seqretry(zone
, seq
));
179 static int page_is_consistent(struct zone
*zone
, struct page
*page
)
181 if (!pfn_valid_within(page_to_pfn(page
)))
183 if (zone
!= page_zone(page
))
189 * Temporary debugging check for pages not lying within a given zone.
191 static int bad_range(struct zone
*zone
, struct page
*page
)
193 if (page_outside_zone_boundaries(zone
, page
))
195 if (!page_is_consistent(zone
, page
))
201 static inline int bad_range(struct zone
*zone
, struct page
*page
)
207 static void bad_page(struct page
*page
)
209 printk(KERN_EMERG
"Bad page state in process '%s'\n"
210 KERN_EMERG
"page:%p flags:0x%0*lx mapping:%p mapcount:%d count:%d\n"
211 KERN_EMERG
"Trying to fix it up, but a reboot is needed\n"
212 KERN_EMERG
"Backtrace:\n",
213 current
->comm
, page
, (int)(2*sizeof(unsigned long)),
214 (unsigned long)page
->flags
, page
->mapping
,
215 page_mapcount(page
), page_count(page
));
217 page
->flags
&= ~(1 << PG_lru
|
227 set_page_count(page
, 0);
228 reset_page_mapcount(page
);
229 page
->mapping
= NULL
;
230 add_taint(TAINT_BAD_PAGE
);
234 * Higher-order pages are called "compound pages". They are structured thusly:
236 * The first PAGE_SIZE page is called the "head page".
238 * The remaining PAGE_SIZE pages are called "tail pages".
240 * All pages have PG_compound set. All pages have their ->private pointing at
241 * the head page (even the head page has this).
243 * The first tail page's ->lru.next holds the address of the compound page's
244 * put_page() function. Its ->lru.prev holds the order of allocation.
245 * This usage means that zero-order pages may not be compound.
248 static void free_compound_page(struct page
*page
)
250 __free_pages_ok(page
, compound_order(page
));
253 static void prep_compound_page(struct page
*page
, unsigned long order
)
256 int nr_pages
= 1 << order
;
258 set_compound_page_dtor(page
, free_compound_page
);
259 set_compound_order(page
, order
);
261 for (i
= 1; i
< nr_pages
; i
++) {
262 struct page
*p
= page
+ i
;
265 p
->first_page
= page
;
269 static void destroy_compound_page(struct page
*page
, unsigned long order
)
272 int nr_pages
= 1 << order
;
274 if (unlikely(compound_order(page
) != order
))
277 if (unlikely(!PageHead(page
)))
279 __ClearPageHead(page
);
280 for (i
= 1; i
< nr_pages
; i
++) {
281 struct page
*p
= page
+ i
;
283 if (unlikely(!PageTail(p
) |
284 (p
->first_page
!= page
)))
290 static inline void prep_zero_page(struct page
*page
, int order
, gfp_t gfp_flags
)
294 VM_BUG_ON((gfp_flags
& (__GFP_WAIT
| __GFP_HIGHMEM
)) == __GFP_HIGHMEM
);
296 * clear_highpage() will use KM_USER0, so it's a bug to use __GFP_ZERO
297 * and __GFP_HIGHMEM from hard or soft interrupt context.
299 VM_BUG_ON((gfp_flags
& __GFP_HIGHMEM
) && in_interrupt());
300 for (i
= 0; i
< (1 << order
); i
++)
301 clear_highpage(page
+ i
);
305 * function for dealing with page's order in buddy system.
306 * zone->lock is already acquired when we use these.
307 * So, we don't need atomic page->flags operations here.
309 static inline unsigned long page_order(struct page
*page
)
311 return page_private(page
);
314 static inline void set_page_order(struct page
*page
, int order
)
316 set_page_private(page
, order
);
317 __SetPageBuddy(page
);
320 static inline void rmv_page_order(struct page
*page
)
322 __ClearPageBuddy(page
);
323 set_page_private(page
, 0);
327 * Locate the struct page for both the matching buddy in our
328 * pair (buddy1) and the combined O(n+1) page they form (page).
330 * 1) Any buddy B1 will have an order O twin B2 which satisfies
331 * the following equation:
333 * For example, if the starting buddy (buddy2) is #8 its order
335 * B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10
337 * 2) Any buddy B will have an order O+1 parent P which
338 * satisfies the following equation:
341 * Assumption: *_mem_map is contiguous at least up to MAX_ORDER
343 static inline struct page
*
344 __page_find_buddy(struct page
*page
, unsigned long page_idx
, unsigned int order
)
346 unsigned long buddy_idx
= page_idx
^ (1 << order
);
348 return page
+ (buddy_idx
- page_idx
);
351 static inline unsigned long
352 __find_combined_index(unsigned long page_idx
, unsigned int order
)
354 return (page_idx
& ~(1 << order
));
358 * This function checks whether a page is free && is the buddy
359 * we can do coalesce a page and its buddy if
360 * (a) the buddy is not in a hole &&
361 * (b) the buddy is in the buddy system &&
362 * (c) a page and its buddy have the same order &&
363 * (d) a page and its buddy are in the same zone.
365 * For recording whether a page is in the buddy system, we use PG_buddy.
366 * Setting, clearing, and testing PG_buddy is serialized by zone->lock.
368 * For recording page's order, we use page_private(page).
370 static inline int page_is_buddy(struct page
*page
, struct page
*buddy
,
373 if (!pfn_valid_within(page_to_pfn(buddy
)))
376 if (page_zone_id(page
) != page_zone_id(buddy
))
379 if (PageBuddy(buddy
) && page_order(buddy
) == order
) {
380 BUG_ON(page_count(buddy
) != 0);
387 * Freeing function for a buddy system allocator.
389 * The concept of a buddy system is to maintain direct-mapped table
390 * (containing bit values) for memory blocks of various "orders".
391 * The bottom level table contains the map for the smallest allocatable
392 * units of memory (here, pages), and each level above it describes
393 * pairs of units from the levels below, hence, "buddies".
394 * At a high level, all that happens here is marking the table entry
395 * at the bottom level available, and propagating the changes upward
396 * as necessary, plus some accounting needed to play nicely with other
397 * parts of the VM system.
398 * At each level, we keep a list of pages, which are heads of continuous
399 * free pages of length of (1 << order) and marked with PG_buddy. Page's
400 * order is recorded in page_private(page) field.
401 * So when we are allocating or freeing one, we can derive the state of the
402 * other. That is, if we allocate a small block, and both were
403 * free, the remainder of the region must be split into blocks.
404 * If a block is freed, and its buddy is also free, then this
405 * triggers coalescing into a block of larger size.
410 static inline void __free_one_page(struct page
*page
,
411 struct zone
*zone
, unsigned int order
)
413 unsigned long page_idx
;
414 int order_size
= 1 << order
;
416 if (unlikely(PageCompound(page
)))
417 destroy_compound_page(page
, order
);
419 page_idx
= page_to_pfn(page
) & ((1 << MAX_ORDER
) - 1);
421 VM_BUG_ON(page_idx
& (order_size
- 1));
422 VM_BUG_ON(bad_range(zone
, page
));
424 __mod_zone_page_state(zone
, NR_FREE_PAGES
, order_size
);
425 while (order
< MAX_ORDER
-1) {
426 unsigned long combined_idx
;
427 struct free_area
*area
;
430 buddy
= __page_find_buddy(page
, page_idx
, order
);
431 if (!page_is_buddy(page
, buddy
, order
))
432 break; /* Move the buddy up one level. */
434 list_del(&buddy
->lru
);
435 area
= zone
->free_area
+ order
;
437 rmv_page_order(buddy
);
438 combined_idx
= __find_combined_index(page_idx
, order
);
439 page
= page
+ (combined_idx
- page_idx
);
440 page_idx
= combined_idx
;
443 set_page_order(page
, order
);
444 list_add(&page
->lru
, &zone
->free_area
[order
].free_list
);
445 zone
->free_area
[order
].nr_free
++;
448 static inline int free_pages_check(struct page
*page
)
450 if (unlikely(page_mapcount(page
) |
451 (page
->mapping
!= NULL
) |
452 (page_count(page
) != 0) |
465 __ClearPageDirty(page
);
467 * For now, we report if PG_reserved was found set, but do not
468 * clear it, and do not free the page. But we shall soon need
469 * to do more, for when the ZERO_PAGE count wraps negative.
471 return PageReserved(page
);
475 * Frees a list of pages.
476 * Assumes all pages on list are in same zone, and of same order.
477 * count is the number of pages to free.
479 * If the zone was previously in an "all pages pinned" state then look to
480 * see if this freeing clears that state.
482 * And clear the zone's pages_scanned counter, to hold off the "all pages are
483 * pinned" detection logic.
485 static void free_pages_bulk(struct zone
*zone
, int count
,
486 struct list_head
*list
, int order
)
488 spin_lock(&zone
->lock
);
489 zone
->all_unreclaimable
= 0;
490 zone
->pages_scanned
= 0;
494 VM_BUG_ON(list_empty(list
));
495 page
= list_entry(list
->prev
, struct page
, lru
);
496 /* have to delete it as __free_one_page list manipulates */
497 list_del(&page
->lru
);
498 __free_one_page(page
, zone
, order
);
500 spin_unlock(&zone
->lock
);
503 static void free_one_page(struct zone
*zone
, struct page
*page
, int order
)
505 spin_lock(&zone
->lock
);
506 zone
->all_unreclaimable
= 0;
507 zone
->pages_scanned
= 0;
508 __free_one_page(page
, zone
, order
);
509 spin_unlock(&zone
->lock
);
512 static void __free_pages_ok(struct page
*page
, unsigned int order
)
518 for (i
= 0 ; i
< (1 << order
) ; ++i
)
519 reserved
+= free_pages_check(page
+ i
);
523 if (!PageHighMem(page
))
524 debug_check_no_locks_freed(page_address(page
),PAGE_SIZE
<<order
);
525 arch_free_page(page
, order
);
526 kernel_map_pages(page
, 1 << order
, 0);
528 local_irq_save(flags
);
529 __count_vm_events(PGFREE
, 1 << order
);
530 free_one_page(page_zone(page
), page
, order
);
531 local_irq_restore(flags
);
535 * permit the bootmem allocator to evade page validation on high-order frees
537 void fastcall __init
__free_pages_bootmem(struct page
*page
, unsigned int order
)
540 __ClearPageReserved(page
);
541 set_page_count(page
, 0);
542 set_page_refcounted(page
);
548 for (loop
= 0; loop
< BITS_PER_LONG
; loop
++) {
549 struct page
*p
= &page
[loop
];
551 if (loop
+ 1 < BITS_PER_LONG
)
553 __ClearPageReserved(p
);
554 set_page_count(p
, 0);
557 set_page_refcounted(page
);
558 __free_pages(page
, order
);
564 * The order of subdivision here is critical for the IO subsystem.
565 * Please do not alter this order without good reasons and regression
566 * testing. Specifically, as large blocks of memory are subdivided,
567 * the order in which smaller blocks are delivered depends on the order
568 * they're subdivided in this function. This is the primary factor
569 * influencing the order in which pages are delivered to the IO
570 * subsystem according to empirical testing, and this is also justified
571 * by considering the behavior of a buddy system containing a single
572 * large block of memory acted on by a series of small allocations.
573 * This behavior is a critical factor in sglist merging's success.
577 static inline void expand(struct zone
*zone
, struct page
*page
,
578 int low
, int high
, struct free_area
*area
)
580 unsigned long size
= 1 << high
;
586 VM_BUG_ON(bad_range(zone
, &page
[size
]));
587 list_add(&page
[size
].lru
, &area
->free_list
);
589 set_page_order(&page
[size
], high
);
594 * This page is about to be returned from the page allocator
596 static int prep_new_page(struct page
*page
, int order
, gfp_t gfp_flags
)
598 if (unlikely(page_mapcount(page
) |
599 (page
->mapping
!= NULL
) |
600 (page_count(page
) != 0) |
615 * For now, we report if PG_reserved was found set, but do not
616 * clear it, and do not allocate the page: as a safety net.
618 if (PageReserved(page
))
621 page
->flags
&= ~(1 << PG_uptodate
| 1 << PG_error
| 1 << PG_readahead
|
622 1 << PG_referenced
| 1 << PG_arch_1
|
623 1 << PG_owner_priv_1
| 1 << PG_mappedtodisk
);
624 set_page_private(page
, 0);
625 set_page_refcounted(page
);
627 arch_alloc_page(page
, order
);
628 kernel_map_pages(page
, 1 << order
, 1);
630 if (gfp_flags
& __GFP_ZERO
)
631 prep_zero_page(page
, order
, gfp_flags
);
633 if (order
&& (gfp_flags
& __GFP_COMP
))
634 prep_compound_page(page
, order
);
640 * Do the hard work of removing an element from the buddy allocator.
641 * Call me with the zone->lock already held.
643 static struct page
*__rmqueue(struct zone
*zone
, unsigned int order
)
645 struct free_area
* area
;
646 unsigned int current_order
;
649 for (current_order
= order
; current_order
< MAX_ORDER
; ++current_order
) {
650 area
= zone
->free_area
+ current_order
;
651 if (list_empty(&area
->free_list
))
654 page
= list_entry(area
->free_list
.next
, struct page
, lru
);
655 list_del(&page
->lru
);
656 rmv_page_order(page
);
658 __mod_zone_page_state(zone
, NR_FREE_PAGES
, - (1UL << order
));
659 expand(zone
, page
, order
, current_order
, area
);
667 * Obtain a specified number of elements from the buddy allocator, all under
668 * a single hold of the lock, for efficiency. Add them to the supplied list.
669 * Returns the number of new pages which were placed at *list.
671 static int rmqueue_bulk(struct zone
*zone
, unsigned int order
,
672 unsigned long count
, struct list_head
*list
)
676 spin_lock(&zone
->lock
);
677 for (i
= 0; i
< count
; ++i
) {
678 struct page
*page
= __rmqueue(zone
, order
);
679 if (unlikely(page
== NULL
))
681 list_add_tail(&page
->lru
, list
);
683 spin_unlock(&zone
->lock
);
689 * Called from the vmstat counter updater to drain pagesets of this
690 * currently executing processor on remote nodes after they have
693 * Note that this function must be called with the thread pinned to
694 * a single processor.
696 void drain_zone_pages(struct zone
*zone
, struct per_cpu_pages
*pcp
)
701 local_irq_save(flags
);
702 if (pcp
->count
>= pcp
->batch
)
703 to_drain
= pcp
->batch
;
705 to_drain
= pcp
->count
;
706 free_pages_bulk(zone
, to_drain
, &pcp
->list
, 0);
707 pcp
->count
-= to_drain
;
708 local_irq_restore(flags
);
712 static void __drain_pages(unsigned int cpu
)
718 for_each_zone(zone
) {
719 struct per_cpu_pageset
*pset
;
721 if (!populated_zone(zone
))
724 pset
= zone_pcp(zone
, cpu
);
725 for (i
= 0; i
< ARRAY_SIZE(pset
->pcp
); i
++) {
726 struct per_cpu_pages
*pcp
;
729 local_irq_save(flags
);
730 free_pages_bulk(zone
, pcp
->count
, &pcp
->list
, 0);
732 local_irq_restore(flags
);
737 #ifdef CONFIG_HIBERNATION
739 void mark_free_pages(struct zone
*zone
)
741 unsigned long pfn
, max_zone_pfn
;
744 struct list_head
*curr
;
746 if (!zone
->spanned_pages
)
749 spin_lock_irqsave(&zone
->lock
, flags
);
751 max_zone_pfn
= zone
->zone_start_pfn
+ zone
->spanned_pages
;
752 for (pfn
= zone
->zone_start_pfn
; pfn
< max_zone_pfn
; pfn
++)
753 if (pfn_valid(pfn
)) {
754 struct page
*page
= pfn_to_page(pfn
);
756 if (!swsusp_page_is_forbidden(page
))
757 swsusp_unset_page_free(page
);
760 for (order
= MAX_ORDER
- 1; order
>= 0; --order
)
761 list_for_each(curr
, &zone
->free_area
[order
].free_list
) {
764 pfn
= page_to_pfn(list_entry(curr
, struct page
, lru
));
765 for (i
= 0; i
< (1UL << order
); i
++)
766 swsusp_set_page_free(pfn_to_page(pfn
+ i
));
769 spin_unlock_irqrestore(&zone
->lock
, flags
);
773 * Spill all of this CPU's per-cpu pages back into the buddy allocator.
775 void drain_local_pages(void)
779 local_irq_save(flags
);
780 __drain_pages(smp_processor_id());
781 local_irq_restore(flags
);
783 #endif /* CONFIG_HIBERNATION */
786 * Free a 0-order page
788 static void fastcall
free_hot_cold_page(struct page
*page
, int cold
)
790 struct zone
*zone
= page_zone(page
);
791 struct per_cpu_pages
*pcp
;
795 page
->mapping
= NULL
;
796 if (free_pages_check(page
))
799 if (!PageHighMem(page
))
800 debug_check_no_locks_freed(page_address(page
), PAGE_SIZE
);
801 arch_free_page(page
, 0);
802 kernel_map_pages(page
, 1, 0);
804 pcp
= &zone_pcp(zone
, get_cpu())->pcp
[cold
];
805 local_irq_save(flags
);
806 __count_vm_event(PGFREE
);
807 list_add(&page
->lru
, &pcp
->list
);
809 if (pcp
->count
>= pcp
->high
) {
810 free_pages_bulk(zone
, pcp
->batch
, &pcp
->list
, 0);
811 pcp
->count
-= pcp
->batch
;
813 local_irq_restore(flags
);
817 void fastcall
free_hot_page(struct page
*page
)
819 free_hot_cold_page(page
, 0);
822 void fastcall
free_cold_page(struct page
*page
)
824 free_hot_cold_page(page
, 1);
828 * split_page takes a non-compound higher-order page, and splits it into
829 * n (1<<order) sub-pages: page[0..n]
830 * Each sub-page must be freed individually.
832 * Note: this is probably too low level an operation for use in drivers.
833 * Please consult with lkml before using this in your driver.
835 void split_page(struct page
*page
, unsigned int order
)
839 VM_BUG_ON(PageCompound(page
));
840 VM_BUG_ON(!page_count(page
));
841 for (i
= 1; i
< (1 << order
); i
++)
842 set_page_refcounted(page
+ i
);
846 * Really, prep_compound_page() should be called from __rmqueue_bulk(). But
847 * we cheat by calling it from here, in the order > 0 path. Saves a branch
850 static struct page
*buffered_rmqueue(struct zonelist
*zonelist
,
851 struct zone
*zone
, int order
, gfp_t gfp_flags
)
855 int cold
= !!(gfp_flags
& __GFP_COLD
);
860 if (likely(order
== 0)) {
861 struct per_cpu_pages
*pcp
;
863 pcp
= &zone_pcp(zone
, cpu
)->pcp
[cold
];
864 local_irq_save(flags
);
866 pcp
->count
= rmqueue_bulk(zone
, 0,
867 pcp
->batch
, &pcp
->list
);
868 if (unlikely(!pcp
->count
))
871 page
= list_entry(pcp
->list
.next
, struct page
, lru
);
872 list_del(&page
->lru
);
875 spin_lock_irqsave(&zone
->lock
, flags
);
876 page
= __rmqueue(zone
, order
);
877 spin_unlock(&zone
->lock
);
882 __count_zone_vm_events(PGALLOC
, zone
, 1 << order
);
883 zone_statistics(zonelist
, zone
);
884 local_irq_restore(flags
);
887 VM_BUG_ON(bad_range(zone
, page
));
888 if (prep_new_page(page
, order
, gfp_flags
))
893 local_irq_restore(flags
);
898 #define ALLOC_NO_WATERMARKS 0x01 /* don't check watermarks at all */
899 #define ALLOC_WMARK_MIN 0x02 /* use pages_min watermark */
900 #define ALLOC_WMARK_LOW 0x04 /* use pages_low watermark */
901 #define ALLOC_WMARK_HIGH 0x08 /* use pages_high watermark */
902 #define ALLOC_HARDER 0x10 /* try to alloc harder */
903 #define ALLOC_HIGH 0x20 /* __GFP_HIGH set */
904 #define ALLOC_CPUSET 0x40 /* check for correct cpuset */
906 #ifdef CONFIG_FAIL_PAGE_ALLOC
908 static struct fail_page_alloc_attr
{
909 struct fault_attr attr
;
911 u32 ignore_gfp_highmem
;
915 #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
917 struct dentry
*ignore_gfp_highmem_file
;
918 struct dentry
*ignore_gfp_wait_file
;
919 struct dentry
*min_order_file
;
921 #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
923 } fail_page_alloc
= {
924 .attr
= FAULT_ATTR_INITIALIZER
,
925 .ignore_gfp_wait
= 1,
926 .ignore_gfp_highmem
= 1,
930 static int __init
setup_fail_page_alloc(char *str
)
932 return setup_fault_attr(&fail_page_alloc
.attr
, str
);
934 __setup("fail_page_alloc=", setup_fail_page_alloc
);
936 static int should_fail_alloc_page(gfp_t gfp_mask
, unsigned int order
)
938 if (order
< fail_page_alloc
.min_order
)
940 if (gfp_mask
& __GFP_NOFAIL
)
942 if (fail_page_alloc
.ignore_gfp_highmem
&& (gfp_mask
& __GFP_HIGHMEM
))
944 if (fail_page_alloc
.ignore_gfp_wait
&& (gfp_mask
& __GFP_WAIT
))
947 return should_fail(&fail_page_alloc
.attr
, 1 << order
);
950 #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
952 static int __init
fail_page_alloc_debugfs(void)
954 mode_t mode
= S_IFREG
| S_IRUSR
| S_IWUSR
;
958 err
= init_fault_attr_dentries(&fail_page_alloc
.attr
,
962 dir
= fail_page_alloc
.attr
.dentries
.dir
;
964 fail_page_alloc
.ignore_gfp_wait_file
=
965 debugfs_create_bool("ignore-gfp-wait", mode
, dir
,
966 &fail_page_alloc
.ignore_gfp_wait
);
968 fail_page_alloc
.ignore_gfp_highmem_file
=
969 debugfs_create_bool("ignore-gfp-highmem", mode
, dir
,
970 &fail_page_alloc
.ignore_gfp_highmem
);
971 fail_page_alloc
.min_order_file
=
972 debugfs_create_u32("min-order", mode
, dir
,
973 &fail_page_alloc
.min_order
);
975 if (!fail_page_alloc
.ignore_gfp_wait_file
||
976 !fail_page_alloc
.ignore_gfp_highmem_file
||
977 !fail_page_alloc
.min_order_file
) {
979 debugfs_remove(fail_page_alloc
.ignore_gfp_wait_file
);
980 debugfs_remove(fail_page_alloc
.ignore_gfp_highmem_file
);
981 debugfs_remove(fail_page_alloc
.min_order_file
);
982 cleanup_fault_attr_dentries(&fail_page_alloc
.attr
);
988 late_initcall(fail_page_alloc_debugfs
);
990 #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
992 #else /* CONFIG_FAIL_PAGE_ALLOC */
994 static inline int should_fail_alloc_page(gfp_t gfp_mask
, unsigned int order
)
999 #endif /* CONFIG_FAIL_PAGE_ALLOC */
1002 * Return 1 if free pages are above 'mark'. This takes into account the order
1003 * of the allocation.
1005 int zone_watermark_ok(struct zone
*z
, int order
, unsigned long mark
,
1006 int classzone_idx
, int alloc_flags
)
1008 /* free_pages my go negative - that's OK */
1010 long free_pages
= zone_page_state(z
, NR_FREE_PAGES
) - (1 << order
) + 1;
1013 if (alloc_flags
& ALLOC_HIGH
)
1015 if (alloc_flags
& ALLOC_HARDER
)
1018 if (free_pages
<= min
+ z
->lowmem_reserve
[classzone_idx
])
1020 for (o
= 0; o
< order
; o
++) {
1021 /* At the next order, this order's pages become unavailable */
1022 free_pages
-= z
->free_area
[o
].nr_free
<< o
;
1024 /* Require fewer higher order pages to be free */
1027 if (free_pages
<= min
)
1035 * zlc_setup - Setup for "zonelist cache". Uses cached zone data to
1036 * skip over zones that are not allowed by the cpuset, or that have
1037 * been recently (in last second) found to be nearly full. See further
1038 * comments in mmzone.h. Reduces cache footprint of zonelist scans
1039 * that have to skip over alot of full or unallowed zones.
1041 * If the zonelist cache is present in the passed in zonelist, then
1042 * returns a pointer to the allowed node mask (either the current
1043 * tasks mems_allowed, or node_online_map.)
1045 * If the zonelist cache is not available for this zonelist, does
1046 * nothing and returns NULL.
1048 * If the fullzones BITMAP in the zonelist cache is stale (more than
1049 * a second since last zap'd) then we zap it out (clear its bits.)
1051 * We hold off even calling zlc_setup, until after we've checked the
1052 * first zone in the zonelist, on the theory that most allocations will
1053 * be satisfied from that first zone, so best to examine that zone as
1054 * quickly as we can.
1056 static nodemask_t
*zlc_setup(struct zonelist
*zonelist
, int alloc_flags
)
1058 struct zonelist_cache
*zlc
; /* cached zonelist speedup info */
1059 nodemask_t
*allowednodes
; /* zonelist_cache approximation */
1061 zlc
= zonelist
->zlcache_ptr
;
1065 if (jiffies
- zlc
->last_full_zap
> 1 * HZ
) {
1066 bitmap_zero(zlc
->fullzones
, MAX_ZONES_PER_ZONELIST
);
1067 zlc
->last_full_zap
= jiffies
;
1070 allowednodes
= !in_interrupt() && (alloc_flags
& ALLOC_CPUSET
) ?
1071 &cpuset_current_mems_allowed
:
1073 return allowednodes
;
1077 * Given 'z' scanning a zonelist, run a couple of quick checks to see
1078 * if it is worth looking at further for free memory:
1079 * 1) Check that the zone isn't thought to be full (doesn't have its
1080 * bit set in the zonelist_cache fullzones BITMAP).
1081 * 2) Check that the zones node (obtained from the zonelist_cache
1082 * z_to_n[] mapping) is allowed in the passed in allowednodes mask.
1083 * Return true (non-zero) if zone is worth looking at further, or
1084 * else return false (zero) if it is not.
1086 * This check -ignores- the distinction between various watermarks,
1087 * such as GFP_HIGH, GFP_ATOMIC, PF_MEMALLOC, ... If a zone is
1088 * found to be full for any variation of these watermarks, it will
1089 * be considered full for up to one second by all requests, unless
1090 * we are so low on memory on all allowed nodes that we are forced
1091 * into the second scan of the zonelist.
1093 * In the second scan we ignore this zonelist cache and exactly
1094 * apply the watermarks to all zones, even it is slower to do so.
1095 * We are low on memory in the second scan, and should leave no stone
1096 * unturned looking for a free page.
1098 static int zlc_zone_worth_trying(struct zonelist
*zonelist
, struct zone
**z
,
1099 nodemask_t
*allowednodes
)
1101 struct zonelist_cache
*zlc
; /* cached zonelist speedup info */
1102 int i
; /* index of *z in zonelist zones */
1103 int n
; /* node that zone *z is on */
1105 zlc
= zonelist
->zlcache_ptr
;
1109 i
= z
- zonelist
->zones
;
1112 /* This zone is worth trying if it is allowed but not full */
1113 return node_isset(n
, *allowednodes
) && !test_bit(i
, zlc
->fullzones
);
1117 * Given 'z' scanning a zonelist, set the corresponding bit in
1118 * zlc->fullzones, so that subsequent attempts to allocate a page
1119 * from that zone don't waste time re-examining it.
1121 static void zlc_mark_zone_full(struct zonelist
*zonelist
, struct zone
**z
)
1123 struct zonelist_cache
*zlc
; /* cached zonelist speedup info */
1124 int i
; /* index of *z in zonelist zones */
1126 zlc
= zonelist
->zlcache_ptr
;
1130 i
= z
- zonelist
->zones
;
1132 set_bit(i
, zlc
->fullzones
);
1135 #else /* CONFIG_NUMA */
1137 static nodemask_t
*zlc_setup(struct zonelist
*zonelist
, int alloc_flags
)
1142 static int zlc_zone_worth_trying(struct zonelist
*zonelist
, struct zone
**z
,
1143 nodemask_t
*allowednodes
)
1148 static void zlc_mark_zone_full(struct zonelist
*zonelist
, struct zone
**z
)
1151 #endif /* CONFIG_NUMA */
1154 * get_page_from_freelist goes through the zonelist trying to allocate
1157 static struct page
*
1158 get_page_from_freelist(gfp_t gfp_mask
, unsigned int order
,
1159 struct zonelist
*zonelist
, int alloc_flags
)
1162 struct page
*page
= NULL
;
1163 int classzone_idx
= zone_idx(zonelist
->zones
[0]);
1165 nodemask_t
*allowednodes
= NULL
;/* zonelist_cache approximation */
1166 int zlc_active
= 0; /* set if using zonelist_cache */
1167 int did_zlc_setup
= 0; /* just call zlc_setup() one time */
1168 enum zone_type highest_zoneidx
= -1; /* Gets set for policy zonelists */
1172 * Scan zonelist, looking for a zone with enough free.
1173 * See also cpuset_zone_allowed() comment in kernel/cpuset.c.
1175 z
= zonelist
->zones
;
1179 * In NUMA, this could be a policy zonelist which contains
1180 * zones that may not be allowed by the current gfp_mask.
1181 * Check the zone is allowed by the current flags
1183 if (unlikely(alloc_should_filter_zonelist(zonelist
))) {
1184 if (highest_zoneidx
== -1)
1185 highest_zoneidx
= gfp_zone(gfp_mask
);
1186 if (zone_idx(*z
) > highest_zoneidx
)
1190 if (NUMA_BUILD
&& zlc_active
&&
1191 !zlc_zone_worth_trying(zonelist
, z
, allowednodes
))
1194 if (unlikely(NUMA_BUILD
&& (gfp_mask
& __GFP_THISNODE
) &&
1195 zone
->zone_pgdat
!= zonelist
->zones
[0]->zone_pgdat
))
1197 if ((alloc_flags
& ALLOC_CPUSET
) &&
1198 !cpuset_zone_allowed_softwall(zone
, gfp_mask
))
1201 if (!(alloc_flags
& ALLOC_NO_WATERMARKS
)) {
1203 if (alloc_flags
& ALLOC_WMARK_MIN
)
1204 mark
= zone
->pages_min
;
1205 else if (alloc_flags
& ALLOC_WMARK_LOW
)
1206 mark
= zone
->pages_low
;
1208 mark
= zone
->pages_high
;
1209 if (!zone_watermark_ok(zone
, order
, mark
,
1210 classzone_idx
, alloc_flags
)) {
1211 if (!zone_reclaim_mode
||
1212 !zone_reclaim(zone
, gfp_mask
, order
))
1213 goto this_zone_full
;
1217 page
= buffered_rmqueue(zonelist
, zone
, order
, gfp_mask
);
1222 zlc_mark_zone_full(zonelist
, z
);
1224 if (NUMA_BUILD
&& !did_zlc_setup
) {
1225 /* we do zlc_setup after the first zone is tried */
1226 allowednodes
= zlc_setup(zonelist
, alloc_flags
);
1230 } while (*(++z
) != NULL
);
1232 if (unlikely(NUMA_BUILD
&& page
== NULL
&& zlc_active
)) {
1233 /* Disable zlc cache for second zonelist scan */
1241 * This is the 'heart' of the zoned buddy allocator.
1243 struct page
* fastcall
1244 __alloc_pages(gfp_t gfp_mask
, unsigned int order
,
1245 struct zonelist
*zonelist
)
1247 const gfp_t wait
= gfp_mask
& __GFP_WAIT
;
1250 struct reclaim_state reclaim_state
;
1251 struct task_struct
*p
= current
;
1254 int did_some_progress
;
1256 might_sleep_if(wait
);
1258 if (should_fail_alloc_page(gfp_mask
, order
))
1262 z
= zonelist
->zones
; /* the list of zones suitable for gfp_mask */
1264 if (unlikely(*z
== NULL
)) {
1265 /* Should this ever happen?? */
1269 page
= get_page_from_freelist(gfp_mask
|__GFP_HARDWALL
, order
,
1270 zonelist
, ALLOC_WMARK_LOW
|ALLOC_CPUSET
);
1275 * GFP_THISNODE (meaning __GFP_THISNODE, __GFP_NORETRY and
1276 * __GFP_NOWARN set) should not cause reclaim since the subsystem
1277 * (f.e. slab) using GFP_THISNODE may choose to trigger reclaim
1278 * using a larger set of nodes after it has established that the
1279 * allowed per node queues are empty and that nodes are
1282 if (NUMA_BUILD
&& (gfp_mask
& GFP_THISNODE
) == GFP_THISNODE
)
1285 for (z
= zonelist
->zones
; *z
; z
++)
1286 wakeup_kswapd(*z
, order
);
1289 * OK, we're below the kswapd watermark and have kicked background
1290 * reclaim. Now things get more complex, so set up alloc_flags according
1291 * to how we want to proceed.
1293 * The caller may dip into page reserves a bit more if the caller
1294 * cannot run direct reclaim, or if the caller has realtime scheduling
1295 * policy or is asking for __GFP_HIGH memory. GFP_ATOMIC requests will
1296 * set both ALLOC_HARDER (!wait) and ALLOC_HIGH (__GFP_HIGH).
1298 alloc_flags
= ALLOC_WMARK_MIN
;
1299 if ((unlikely(rt_task(p
)) && !in_interrupt()) || !wait
)
1300 alloc_flags
|= ALLOC_HARDER
;
1301 if (gfp_mask
& __GFP_HIGH
)
1302 alloc_flags
|= ALLOC_HIGH
;
1304 alloc_flags
|= ALLOC_CPUSET
;
1307 * Go through the zonelist again. Let __GFP_HIGH and allocations
1308 * coming from realtime tasks go deeper into reserves.
1310 * This is the last chance, in general, before the goto nopage.
1311 * Ignore cpuset if GFP_ATOMIC (!wait) rather than fail alloc.
1312 * See also cpuset_zone_allowed() comment in kernel/cpuset.c.
1314 page
= get_page_from_freelist(gfp_mask
, order
, zonelist
, alloc_flags
);
1318 /* This allocation should allow future memory freeing. */
1321 if (((p
->flags
& PF_MEMALLOC
) || unlikely(test_thread_flag(TIF_MEMDIE
)))
1322 && !in_interrupt()) {
1323 if (!(gfp_mask
& __GFP_NOMEMALLOC
)) {
1325 /* go through the zonelist yet again, ignoring mins */
1326 page
= get_page_from_freelist(gfp_mask
, order
,
1327 zonelist
, ALLOC_NO_WATERMARKS
);
1330 if (gfp_mask
& __GFP_NOFAIL
) {
1331 congestion_wait(WRITE
, HZ
/50);
1338 /* Atomic allocations - we can't balance anything */
1344 /* We now go into synchronous reclaim */
1345 cpuset_memory_pressure_bump();
1346 p
->flags
|= PF_MEMALLOC
;
1347 reclaim_state
.reclaimed_slab
= 0;
1348 p
->reclaim_state
= &reclaim_state
;
1350 did_some_progress
= try_to_free_pages(zonelist
->zones
, order
, gfp_mask
);
1352 p
->reclaim_state
= NULL
;
1353 p
->flags
&= ~PF_MEMALLOC
;
1357 if (likely(did_some_progress
)) {
1358 page
= get_page_from_freelist(gfp_mask
, order
,
1359 zonelist
, alloc_flags
);
1362 } else if ((gfp_mask
& __GFP_FS
) && !(gfp_mask
& __GFP_NORETRY
)) {
1364 * Go through the zonelist yet one more time, keep
1365 * very high watermark here, this is only to catch
1366 * a parallel oom killing, we must fail if we're still
1367 * under heavy pressure.
1369 page
= get_page_from_freelist(gfp_mask
|__GFP_HARDWALL
, order
,
1370 zonelist
, ALLOC_WMARK_HIGH
|ALLOC_CPUSET
);
1374 /* The OOM killer will not help higher order allocs so fail */
1375 if (order
> PAGE_ALLOC_COSTLY_ORDER
)
1378 out_of_memory(zonelist
, gfp_mask
, order
);
1383 * Don't let big-order allocations loop unless the caller explicitly
1384 * requests that. Wait for some write requests to complete then retry.
1386 * In this implementation, __GFP_REPEAT means __GFP_NOFAIL for order
1387 * <= 3, but that may not be true in other implementations.
1390 if (!(gfp_mask
& __GFP_NORETRY
)) {
1391 if ((order
<= PAGE_ALLOC_COSTLY_ORDER
) ||
1392 (gfp_mask
& __GFP_REPEAT
))
1394 if (gfp_mask
& __GFP_NOFAIL
)
1398 congestion_wait(WRITE
, HZ
/50);
1403 if (!(gfp_mask
& __GFP_NOWARN
) && printk_ratelimit()) {
1404 printk(KERN_WARNING
"%s: page allocation failure."
1405 " order:%d, mode:0x%x\n",
1406 p
->comm
, order
, gfp_mask
);
1414 EXPORT_SYMBOL(__alloc_pages
);
1417 * Common helper functions.
1419 fastcall
unsigned long __get_free_pages(gfp_t gfp_mask
, unsigned int order
)
1422 page
= alloc_pages(gfp_mask
, order
);
1425 return (unsigned long) page_address(page
);
1428 EXPORT_SYMBOL(__get_free_pages
);
1430 fastcall
unsigned long get_zeroed_page(gfp_t gfp_mask
)
1435 * get_zeroed_page() returns a 32-bit address, which cannot represent
1438 VM_BUG_ON((gfp_mask
& __GFP_HIGHMEM
) != 0);
1440 page
= alloc_pages(gfp_mask
| __GFP_ZERO
, 0);
1442 return (unsigned long) page_address(page
);
1446 EXPORT_SYMBOL(get_zeroed_page
);
1448 void __pagevec_free(struct pagevec
*pvec
)
1450 int i
= pagevec_count(pvec
);
1453 free_hot_cold_page(pvec
->pages
[i
], pvec
->cold
);
1456 fastcall
void __free_pages(struct page
*page
, unsigned int order
)
1458 if (put_page_testzero(page
)) {
1460 free_hot_page(page
);
1462 __free_pages_ok(page
, order
);
1466 EXPORT_SYMBOL(__free_pages
);
1468 fastcall
void free_pages(unsigned long addr
, unsigned int order
)
1471 VM_BUG_ON(!virt_addr_valid((void *)addr
));
1472 __free_pages(virt_to_page((void *)addr
), order
);
1476 EXPORT_SYMBOL(free_pages
);
1478 static unsigned int nr_free_zone_pages(int offset
)
1480 /* Just pick one node, since fallback list is circular */
1481 pg_data_t
*pgdat
= NODE_DATA(numa_node_id());
1482 unsigned int sum
= 0;
1484 struct zonelist
*zonelist
= pgdat
->node_zonelists
+ offset
;
1485 struct zone
**zonep
= zonelist
->zones
;
1488 for (zone
= *zonep
++; zone
; zone
= *zonep
++) {
1489 unsigned long size
= zone
->present_pages
;
1490 unsigned long high
= zone
->pages_high
;
1499 * Amount of free RAM allocatable within ZONE_DMA and ZONE_NORMAL
1501 unsigned int nr_free_buffer_pages(void)
1503 return nr_free_zone_pages(gfp_zone(GFP_USER
));
1505 EXPORT_SYMBOL_GPL(nr_free_buffer_pages
);
1508 * Amount of free RAM allocatable within all zones
1510 unsigned int nr_free_pagecache_pages(void)
1512 return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE
));
1515 static inline void show_node(struct zone
*zone
)
1518 printk("Node %d ", zone_to_nid(zone
));
1521 void si_meminfo(struct sysinfo
*val
)
1523 val
->totalram
= totalram_pages
;
1525 val
->freeram
= global_page_state(NR_FREE_PAGES
);
1526 val
->bufferram
= nr_blockdev_pages();
1527 val
->totalhigh
= totalhigh_pages
;
1528 val
->freehigh
= nr_free_highpages();
1529 val
->mem_unit
= PAGE_SIZE
;
1532 EXPORT_SYMBOL(si_meminfo
);
1535 void si_meminfo_node(struct sysinfo
*val
, int nid
)
1537 pg_data_t
*pgdat
= NODE_DATA(nid
);
1539 val
->totalram
= pgdat
->node_present_pages
;
1540 val
->freeram
= node_page_state(nid
, NR_FREE_PAGES
);
1541 #ifdef CONFIG_HIGHMEM
1542 val
->totalhigh
= pgdat
->node_zones
[ZONE_HIGHMEM
].present_pages
;
1543 val
->freehigh
= zone_page_state(&pgdat
->node_zones
[ZONE_HIGHMEM
],
1549 val
->mem_unit
= PAGE_SIZE
;
1553 #define K(x) ((x) << (PAGE_SHIFT-10))
1556 * Show free area list (used inside shift_scroll-lock stuff)
1557 * We also calculate the percentage fragmentation. We do this by counting the
1558 * memory on each free list with the exception of the first item on the list.
1560 void show_free_areas(void)
1565 for_each_zone(zone
) {
1566 if (!populated_zone(zone
))
1570 printk("%s per-cpu:\n", zone
->name
);
1572 for_each_online_cpu(cpu
) {
1573 struct per_cpu_pageset
*pageset
;
1575 pageset
= zone_pcp(zone
, cpu
);
1577 printk("CPU %4d: Hot: hi:%5d, btch:%4d usd:%4d "
1578 "Cold: hi:%5d, btch:%4d usd:%4d\n",
1579 cpu
, pageset
->pcp
[0].high
,
1580 pageset
->pcp
[0].batch
, pageset
->pcp
[0].count
,
1581 pageset
->pcp
[1].high
, pageset
->pcp
[1].batch
,
1582 pageset
->pcp
[1].count
);
1586 printk("Active:%lu inactive:%lu dirty:%lu writeback:%lu unstable:%lu\n"
1587 " free:%lu slab:%lu mapped:%lu pagetables:%lu bounce:%lu\n",
1588 global_page_state(NR_ACTIVE
),
1589 global_page_state(NR_INACTIVE
),
1590 global_page_state(NR_FILE_DIRTY
),
1591 global_page_state(NR_WRITEBACK
),
1592 global_page_state(NR_UNSTABLE_NFS
),
1593 global_page_state(NR_FREE_PAGES
),
1594 global_page_state(NR_SLAB_RECLAIMABLE
) +
1595 global_page_state(NR_SLAB_UNRECLAIMABLE
),
1596 global_page_state(NR_FILE_MAPPED
),
1597 global_page_state(NR_PAGETABLE
),
1598 global_page_state(NR_BOUNCE
));
1600 for_each_zone(zone
) {
1603 if (!populated_zone(zone
))
1615 " pages_scanned:%lu"
1616 " all_unreclaimable? %s"
1619 K(zone_page_state(zone
, NR_FREE_PAGES
)),
1622 K(zone
->pages_high
),
1623 K(zone_page_state(zone
, NR_ACTIVE
)),
1624 K(zone_page_state(zone
, NR_INACTIVE
)),
1625 K(zone
->present_pages
),
1626 zone
->pages_scanned
,
1627 (zone
->all_unreclaimable
? "yes" : "no")
1629 printk("lowmem_reserve[]:");
1630 for (i
= 0; i
< MAX_NR_ZONES
; i
++)
1631 printk(" %lu", zone
->lowmem_reserve
[i
]);
1635 for_each_zone(zone
) {
1636 unsigned long nr
[MAX_ORDER
], flags
, order
, total
= 0;
1638 if (!populated_zone(zone
))
1642 printk("%s: ", zone
->name
);
1644 spin_lock_irqsave(&zone
->lock
, flags
);
1645 for (order
= 0; order
< MAX_ORDER
; order
++) {
1646 nr
[order
] = zone
->free_area
[order
].nr_free
;
1647 total
+= nr
[order
] << order
;
1649 spin_unlock_irqrestore(&zone
->lock
, flags
);
1650 for (order
= 0; order
< MAX_ORDER
; order
++)
1651 printk("%lu*%lukB ", nr
[order
], K(1UL) << order
);
1652 printk("= %lukB\n", K(total
));
1655 show_swap_cache_info();
1659 * Builds allocation fallback zone lists.
1661 * Add all populated zones of a node to the zonelist.
1663 static int build_zonelists_node(pg_data_t
*pgdat
, struct zonelist
*zonelist
,
1664 int nr_zones
, enum zone_type zone_type
)
1668 BUG_ON(zone_type
>= MAX_NR_ZONES
);
1673 zone
= pgdat
->node_zones
+ zone_type
;
1674 if (populated_zone(zone
)) {
1675 zonelist
->zones
[nr_zones
++] = zone
;
1676 check_highest_zone(zone_type
);
1679 } while (zone_type
);
1686 * 0 = automatic detection of better ordering.
1687 * 1 = order by ([node] distance, -zonetype)
1688 * 2 = order by (-zonetype, [node] distance)
1690 * If not NUMA, ZONELIST_ORDER_ZONE and ZONELIST_ORDER_NODE will create
1691 * the same zonelist. So only NUMA can configure this param.
1693 #define ZONELIST_ORDER_DEFAULT 0
1694 #define ZONELIST_ORDER_NODE 1
1695 #define ZONELIST_ORDER_ZONE 2
1697 /* zonelist order in the kernel.
1698 * set_zonelist_order() will set this to NODE or ZONE.
1700 static int current_zonelist_order
= ZONELIST_ORDER_DEFAULT
;
1701 static char zonelist_order_name
[3][8] = {"Default", "Node", "Zone"};
1705 /* The value user specified ....changed by config */
1706 static int user_zonelist_order
= ZONELIST_ORDER_DEFAULT
;
1707 /* string for sysctl */
1708 #define NUMA_ZONELIST_ORDER_LEN 16
1709 char numa_zonelist_order
[16] = "default";
1712 * interface for configure zonelist ordering.
1713 * command line option "numa_zonelist_order"
1714 * = "[dD]efault - default, automatic configuration.
1715 * = "[nN]ode - order by node locality, then by zone within node
1716 * = "[zZ]one - order by zone, then by locality within zone
1719 static int __parse_numa_zonelist_order(char *s
)
1721 if (*s
== 'd' || *s
== 'D') {
1722 user_zonelist_order
= ZONELIST_ORDER_DEFAULT
;
1723 } else if (*s
== 'n' || *s
== 'N') {
1724 user_zonelist_order
= ZONELIST_ORDER_NODE
;
1725 } else if (*s
== 'z' || *s
== 'Z') {
1726 user_zonelist_order
= ZONELIST_ORDER_ZONE
;
1729 "Ignoring invalid numa_zonelist_order value: "
1736 static __init
int setup_numa_zonelist_order(char *s
)
1739 return __parse_numa_zonelist_order(s
);
1742 early_param("numa_zonelist_order", setup_numa_zonelist_order
);
1745 * sysctl handler for numa_zonelist_order
1747 int numa_zonelist_order_handler(ctl_table
*table
, int write
,
1748 struct file
*file
, void __user
*buffer
, size_t *length
,
1751 char saved_string
[NUMA_ZONELIST_ORDER_LEN
];
1755 strncpy(saved_string
, (char*)table
->data
,
1756 NUMA_ZONELIST_ORDER_LEN
);
1757 ret
= proc_dostring(table
, write
, file
, buffer
, length
, ppos
);
1761 int oldval
= user_zonelist_order
;
1762 if (__parse_numa_zonelist_order((char*)table
->data
)) {
1764 * bogus value. restore saved string
1766 strncpy((char*)table
->data
, saved_string
,
1767 NUMA_ZONELIST_ORDER_LEN
);
1768 user_zonelist_order
= oldval
;
1769 } else if (oldval
!= user_zonelist_order
)
1770 build_all_zonelists();
1776 #define MAX_NODE_LOAD (num_online_nodes())
1777 static int node_load
[MAX_NUMNODES
];
1780 * find_next_best_node - find the next node that should appear in a given node's fallback list
1781 * @node: node whose fallback list we're appending
1782 * @used_node_mask: nodemask_t of already used nodes
1784 * We use a number of factors to determine which is the next node that should
1785 * appear on a given node's fallback list. The node should not have appeared
1786 * already in @node's fallback list, and it should be the next closest node
1787 * according to the distance array (which contains arbitrary distance values
1788 * from each node to each node in the system), and should also prefer nodes
1789 * with no CPUs, since presumably they'll have very little allocation pressure
1790 * on them otherwise.
1791 * It returns -1 if no node is found.
1793 static int find_next_best_node(int node
, nodemask_t
*used_node_mask
)
1796 int min_val
= INT_MAX
;
1799 /* Use the local node if we haven't already */
1800 if (!node_isset(node
, *used_node_mask
)) {
1801 node_set(node
, *used_node_mask
);
1805 for_each_online_node(n
) {
1808 /* Don't want a node to appear more than once */
1809 if (node_isset(n
, *used_node_mask
))
1812 /* Use the distance array to find the distance */
1813 val
= node_distance(node
, n
);
1815 /* Penalize nodes under us ("prefer the next node") */
1818 /* Give preference to headless and unused nodes */
1819 tmp
= node_to_cpumask(n
);
1820 if (!cpus_empty(tmp
))
1821 val
+= PENALTY_FOR_NODE_WITH_CPUS
;
1823 /* Slight preference for less loaded node */
1824 val
*= (MAX_NODE_LOAD
*MAX_NUMNODES
);
1825 val
+= node_load
[n
];
1827 if (val
< min_val
) {
1834 node_set(best_node
, *used_node_mask
);
1841 * Build zonelists ordered by node and zones within node.
1842 * This results in maximum locality--normal zone overflows into local
1843 * DMA zone, if any--but risks exhausting DMA zone.
1845 static void build_zonelists_in_node_order(pg_data_t
*pgdat
, int node
)
1849 struct zonelist
*zonelist
;
1851 for (i
= 0; i
< MAX_NR_ZONES
; i
++) {
1852 zonelist
= pgdat
->node_zonelists
+ i
;
1853 for (j
= 0; zonelist
->zones
[j
] != NULL
; j
++)
1855 j
= build_zonelists_node(NODE_DATA(node
), zonelist
, j
, i
);
1856 zonelist
->zones
[j
] = NULL
;
1861 * Build zonelists ordered by zone and nodes within zones.
1862 * This results in conserving DMA zone[s] until all Normal memory is
1863 * exhausted, but results in overflowing to remote node while memory
1864 * may still exist in local DMA zone.
1866 static int node_order
[MAX_NUMNODES
];
1868 static void build_zonelists_in_zone_order(pg_data_t
*pgdat
, int nr_nodes
)
1872 int zone_type
; /* needs to be signed */
1874 struct zonelist
*zonelist
;
1876 for (i
= 0; i
< MAX_NR_ZONES
; i
++) {
1877 zonelist
= pgdat
->node_zonelists
+ i
;
1879 for (zone_type
= i
; zone_type
>= 0; zone_type
--) {
1880 for (j
= 0; j
< nr_nodes
; j
++) {
1881 node
= node_order
[j
];
1882 z
= &NODE_DATA(node
)->node_zones
[zone_type
];
1883 if (populated_zone(z
)) {
1884 zonelist
->zones
[pos
++] = z
;
1885 check_highest_zone(zone_type
);
1889 zonelist
->zones
[pos
] = NULL
;
1893 static int default_zonelist_order(void)
1896 unsigned long low_kmem_size
,total_size
;
1900 * ZONE_DMA and ZONE_DMA32 can be very small area in the sytem.
1901 * If they are really small and used heavily, the system can fall
1902 * into OOM very easily.
1903 * This function detect ZONE_DMA/DMA32 size and confgigures zone order.
1905 /* Is there ZONE_NORMAL ? (ex. ppc has only DMA zone..) */
1908 for_each_online_node(nid
) {
1909 for (zone_type
= 0; zone_type
< MAX_NR_ZONES
; zone_type
++) {
1910 z
= &NODE_DATA(nid
)->node_zones
[zone_type
];
1911 if (populated_zone(z
)) {
1912 if (zone_type
< ZONE_NORMAL
)
1913 low_kmem_size
+= z
->present_pages
;
1914 total_size
+= z
->present_pages
;
1918 if (!low_kmem_size
|| /* there are no DMA area. */
1919 low_kmem_size
> total_size
/2) /* DMA/DMA32 is big. */
1920 return ZONELIST_ORDER_NODE
;
1922 * look into each node's config.
1923 * If there is a node whose DMA/DMA32 memory is very big area on
1924 * local memory, NODE_ORDER may be suitable.
1926 average_size
= total_size
/ (num_online_nodes() + 1);
1927 for_each_online_node(nid
) {
1930 for (zone_type
= 0; zone_type
< MAX_NR_ZONES
; zone_type
++) {
1931 z
= &NODE_DATA(nid
)->node_zones
[zone_type
];
1932 if (populated_zone(z
)) {
1933 if (zone_type
< ZONE_NORMAL
)
1934 low_kmem_size
+= z
->present_pages
;
1935 total_size
+= z
->present_pages
;
1938 if (low_kmem_size
&&
1939 total_size
> average_size
&& /* ignore small node */
1940 low_kmem_size
> total_size
* 70/100)
1941 return ZONELIST_ORDER_NODE
;
1943 return ZONELIST_ORDER_ZONE
;
1946 static void set_zonelist_order(void)
1948 if (user_zonelist_order
== ZONELIST_ORDER_DEFAULT
)
1949 current_zonelist_order
= default_zonelist_order();
1951 current_zonelist_order
= user_zonelist_order
;
1954 static void build_zonelists(pg_data_t
*pgdat
)
1958 nodemask_t used_mask
;
1959 int local_node
, prev_node
;
1960 struct zonelist
*zonelist
;
1961 int order
= current_zonelist_order
;
1963 /* initialize zonelists */
1964 for (i
= 0; i
< MAX_NR_ZONES
; i
++) {
1965 zonelist
= pgdat
->node_zonelists
+ i
;
1966 zonelist
->zones
[0] = NULL
;
1969 /* NUMA-aware ordering of nodes */
1970 local_node
= pgdat
->node_id
;
1971 load
= num_online_nodes();
1972 prev_node
= local_node
;
1973 nodes_clear(used_mask
);
1975 memset(node_load
, 0, sizeof(node_load
));
1976 memset(node_order
, 0, sizeof(node_order
));
1979 while ((node
= find_next_best_node(local_node
, &used_mask
)) >= 0) {
1980 int distance
= node_distance(local_node
, node
);
1983 * If another node is sufficiently far away then it is better
1984 * to reclaim pages in a zone before going off node.
1986 if (distance
> RECLAIM_DISTANCE
)
1987 zone_reclaim_mode
= 1;
1990 * We don't want to pressure a particular node.
1991 * So adding penalty to the first node in same
1992 * distance group to make it round-robin.
1994 if (distance
!= node_distance(local_node
, prev_node
))
1995 node_load
[node
] = load
;
1999 if (order
== ZONELIST_ORDER_NODE
)
2000 build_zonelists_in_node_order(pgdat
, node
);
2002 node_order
[j
++] = node
; /* remember order */
2005 if (order
== ZONELIST_ORDER_ZONE
) {
2006 /* calculate node order -- i.e., DMA last! */
2007 build_zonelists_in_zone_order(pgdat
, j
);
2011 /* Construct the zonelist performance cache - see further mmzone.h */
2012 static void build_zonelist_cache(pg_data_t
*pgdat
)
2016 for (i
= 0; i
< MAX_NR_ZONES
; i
++) {
2017 struct zonelist
*zonelist
;
2018 struct zonelist_cache
*zlc
;
2021 zonelist
= pgdat
->node_zonelists
+ i
;
2022 zonelist
->zlcache_ptr
= zlc
= &zonelist
->zlcache
;
2023 bitmap_zero(zlc
->fullzones
, MAX_ZONES_PER_ZONELIST
);
2024 for (z
= zonelist
->zones
; *z
; z
++)
2025 zlc
->z_to_n
[z
- zonelist
->zones
] = zone_to_nid(*z
);
2030 #else /* CONFIG_NUMA */
2032 static void set_zonelist_order(void)
2034 current_zonelist_order
= ZONELIST_ORDER_ZONE
;
2037 static void build_zonelists(pg_data_t
*pgdat
)
2039 int node
, local_node
;
2042 local_node
= pgdat
->node_id
;
2043 for (i
= 0; i
< MAX_NR_ZONES
; i
++) {
2044 struct zonelist
*zonelist
;
2046 zonelist
= pgdat
->node_zonelists
+ i
;
2048 j
= build_zonelists_node(pgdat
, zonelist
, 0, i
);
2050 * Now we build the zonelist so that it contains the zones
2051 * of all the other nodes.
2052 * We don't want to pressure a particular node, so when
2053 * building the zones for node N, we make sure that the
2054 * zones coming right after the local ones are those from
2055 * node N+1 (modulo N)
2057 for (node
= local_node
+ 1; node
< MAX_NUMNODES
; node
++) {
2058 if (!node_online(node
))
2060 j
= build_zonelists_node(NODE_DATA(node
), zonelist
, j
, i
);
2062 for (node
= 0; node
< local_node
; node
++) {
2063 if (!node_online(node
))
2065 j
= build_zonelists_node(NODE_DATA(node
), zonelist
, j
, i
);
2068 zonelist
->zones
[j
] = NULL
;
2072 /* non-NUMA variant of zonelist performance cache - just NULL zlcache_ptr */
2073 static void build_zonelist_cache(pg_data_t
*pgdat
)
2077 for (i
= 0; i
< MAX_NR_ZONES
; i
++)
2078 pgdat
->node_zonelists
[i
].zlcache_ptr
= NULL
;
2081 #endif /* CONFIG_NUMA */
2083 /* Any regular memory on that node ? */
2084 static void check_for_regular_memory(pg_data_t
*pgdat
)
2086 #ifdef CONFIG_HIGHMEM
2087 enum zone_type zone_type
;
2089 for (zone_type
= 0; zone_type
<= ZONE_NORMAL
; zone_type
++) {
2090 struct zone
*zone
= &pgdat
->node_zones
[zone_type
];
2091 if (zone
->present_pages
)
2092 node_set_state(zone_to_nid(zone
), N_NORMAL_MEMORY
);
2097 /* return values int ....just for stop_machine_run() */
2098 static int __build_all_zonelists(void *dummy
)
2102 for_each_online_node(nid
) {
2103 pg_data_t
*pgdat
= NODE_DATA(nid
);
2105 build_zonelists(pgdat
);
2106 build_zonelist_cache(pgdat
);
2108 /* Any memory on that node */
2109 if (pgdat
->node_present_pages
)
2110 node_set_state(nid
, N_HIGH_MEMORY
);
2111 check_for_regular_memory(pgdat
);
2116 void build_all_zonelists(void)
2118 set_zonelist_order();
2120 if (system_state
== SYSTEM_BOOTING
) {
2121 __build_all_zonelists(NULL
);
2122 cpuset_init_current_mems_allowed();
2124 /* we have to stop all cpus to guaranntee there is no user
2126 stop_machine_run(__build_all_zonelists
, NULL
, NR_CPUS
);
2127 /* cpuset refresh routine should be here */
2129 vm_total_pages
= nr_free_pagecache_pages();
2130 printk("Built %i zonelists in %s order. Total pages: %ld\n",
2132 zonelist_order_name
[current_zonelist_order
],
2135 printk("Policy zone: %s\n", zone_names
[policy_zone
]);
2140 * Helper functions to size the waitqueue hash table.
2141 * Essentially these want to choose hash table sizes sufficiently
2142 * large so that collisions trying to wait on pages are rare.
2143 * But in fact, the number of active page waitqueues on typical
2144 * systems is ridiculously low, less than 200. So this is even
2145 * conservative, even though it seems large.
2147 * The constant PAGES_PER_WAITQUEUE specifies the ratio of pages to
2148 * waitqueues, i.e. the size of the waitq table given the number of pages.
2150 #define PAGES_PER_WAITQUEUE 256
2152 #ifndef CONFIG_MEMORY_HOTPLUG
2153 static inline unsigned long wait_table_hash_nr_entries(unsigned long pages
)
2155 unsigned long size
= 1;
2157 pages
/= PAGES_PER_WAITQUEUE
;
2159 while (size
< pages
)
2163 * Once we have dozens or even hundreds of threads sleeping
2164 * on IO we've got bigger problems than wait queue collision.
2165 * Limit the size of the wait table to a reasonable size.
2167 size
= min(size
, 4096UL);
2169 return max(size
, 4UL);
2173 * A zone's size might be changed by hot-add, so it is not possible to determine
2174 * a suitable size for its wait_table. So we use the maximum size now.
2176 * The max wait table size = 4096 x sizeof(wait_queue_head_t). ie:
2178 * i386 (preemption config) : 4096 x 16 = 64Kbyte.
2179 * ia64, x86-64 (no preemption): 4096 x 20 = 80Kbyte.
2180 * ia64, x86-64 (preemption) : 4096 x 24 = 96Kbyte.
2182 * The maximum entries are prepared when a zone's memory is (512K + 256) pages
2183 * or more by the traditional way. (See above). It equals:
2185 * i386, x86-64, powerpc(4K page size) : = ( 2G + 1M)byte.
2186 * ia64(16K page size) : = ( 8G + 4M)byte.
2187 * powerpc (64K page size) : = (32G +16M)byte.
2189 static inline unsigned long wait_table_hash_nr_entries(unsigned long pages
)
2196 * This is an integer logarithm so that shifts can be used later
2197 * to extract the more random high bits from the multiplicative
2198 * hash function before the remainder is taken.
2200 static inline unsigned long wait_table_bits(unsigned long size
)
2205 #define LONG_ALIGN(x) (((x)+(sizeof(long))-1)&~((sizeof(long))-1))
2208 * Initially all pages are reserved - free ones are freed
2209 * up by free_all_bootmem() once the early boot process is
2210 * done. Non-atomic initialization, single-pass.
2212 void __meminit
memmap_init_zone(unsigned long size
, int nid
, unsigned long zone
,
2213 unsigned long start_pfn
, enum memmap_context context
)
2216 unsigned long end_pfn
= start_pfn
+ size
;
2219 for (pfn
= start_pfn
; pfn
< end_pfn
; pfn
++) {
2221 * There can be holes in boot-time mem_map[]s
2222 * handed to this function. They do not
2223 * exist on hotplugged memory.
2225 if (context
== MEMMAP_EARLY
) {
2226 if (!early_pfn_valid(pfn
))
2228 if (!early_pfn_in_nid(pfn
, nid
))
2231 page
= pfn_to_page(pfn
);
2232 set_page_links(page
, zone
, nid
, pfn
);
2233 init_page_count(page
);
2234 reset_page_mapcount(page
);
2235 SetPageReserved(page
);
2236 INIT_LIST_HEAD(&page
->lru
);
2237 #ifdef WANT_PAGE_VIRTUAL
2238 /* The shift won't overflow because ZONE_NORMAL is below 4G. */
2239 if (!is_highmem_idx(zone
))
2240 set_page_address(page
, __va(pfn
<< PAGE_SHIFT
));
2245 static void __meminit
zone_init_free_lists(struct pglist_data
*pgdat
,
2246 struct zone
*zone
, unsigned long size
)
2249 for (order
= 0; order
< MAX_ORDER
; order
++) {
2250 INIT_LIST_HEAD(&zone
->free_area
[order
].free_list
);
2251 zone
->free_area
[order
].nr_free
= 0;
2255 #ifndef __HAVE_ARCH_MEMMAP_INIT
2256 #define memmap_init(size, nid, zone, start_pfn) \
2257 memmap_init_zone((size), (nid), (zone), (start_pfn), MEMMAP_EARLY)
2260 static int __devinit
zone_batchsize(struct zone
*zone
)
2265 * The per-cpu-pages pools are set to around 1000th of the
2266 * size of the zone. But no more than 1/2 of a meg.
2268 * OK, so we don't know how big the cache is. So guess.
2270 batch
= zone
->present_pages
/ 1024;
2271 if (batch
* PAGE_SIZE
> 512 * 1024)
2272 batch
= (512 * 1024) / PAGE_SIZE
;
2273 batch
/= 4; /* We effectively *= 4 below */
2278 * Clamp the batch to a 2^n - 1 value. Having a power
2279 * of 2 value was found to be more likely to have
2280 * suboptimal cache aliasing properties in some cases.
2282 * For example if 2 tasks are alternately allocating
2283 * batches of pages, one task can end up with a lot
2284 * of pages of one half of the possible page colors
2285 * and the other with pages of the other colors.
2287 batch
= (1 << (fls(batch
+ batch
/2)-1)) - 1;
2292 inline void setup_pageset(struct per_cpu_pageset
*p
, unsigned long batch
)
2294 struct per_cpu_pages
*pcp
;
2296 memset(p
, 0, sizeof(*p
));
2298 pcp
= &p
->pcp
[0]; /* hot */
2300 pcp
->high
= 6 * batch
;
2301 pcp
->batch
= max(1UL, 1 * batch
);
2302 INIT_LIST_HEAD(&pcp
->list
);
2304 pcp
= &p
->pcp
[1]; /* cold*/
2306 pcp
->high
= 2 * batch
;
2307 pcp
->batch
= max(1UL, batch
/2);
2308 INIT_LIST_HEAD(&pcp
->list
);
2312 * setup_pagelist_highmark() sets the high water mark for hot per_cpu_pagelist
2313 * to the value high for the pageset p.
2316 static void setup_pagelist_highmark(struct per_cpu_pageset
*p
,
2319 struct per_cpu_pages
*pcp
;
2321 pcp
= &p
->pcp
[0]; /* hot list */
2323 pcp
->batch
= max(1UL, high
/4);
2324 if ((high
/4) > (PAGE_SHIFT
* 8))
2325 pcp
->batch
= PAGE_SHIFT
* 8;
2331 * Boot pageset table. One per cpu which is going to be used for all
2332 * zones and all nodes. The parameters will be set in such a way
2333 * that an item put on a list will immediately be handed over to
2334 * the buddy list. This is safe since pageset manipulation is done
2335 * with interrupts disabled.
2337 * Some NUMA counter updates may also be caught by the boot pagesets.
2339 * The boot_pagesets must be kept even after bootup is complete for
2340 * unused processors and/or zones. They do play a role for bootstrapping
2341 * hotplugged processors.
2343 * zoneinfo_show() and maybe other functions do
2344 * not check if the processor is online before following the pageset pointer.
2345 * Other parts of the kernel may not check if the zone is available.
2347 static struct per_cpu_pageset boot_pageset
[NR_CPUS
];
2350 * Dynamically allocate memory for the
2351 * per cpu pageset array in struct zone.
2353 static int __cpuinit
process_zones(int cpu
)
2355 struct zone
*zone
, *dzone
;
2356 int node
= cpu_to_node(cpu
);
2358 node_set_state(node
, N_CPU
); /* this node has a cpu */
2360 for_each_zone(zone
) {
2362 if (!populated_zone(zone
))
2365 zone_pcp(zone
, cpu
) = kmalloc_node(sizeof(struct per_cpu_pageset
),
2367 if (!zone_pcp(zone
, cpu
))
2370 setup_pageset(zone_pcp(zone
, cpu
), zone_batchsize(zone
));
2372 if (percpu_pagelist_fraction
)
2373 setup_pagelist_highmark(zone_pcp(zone
, cpu
),
2374 (zone
->present_pages
/ percpu_pagelist_fraction
));
2379 for_each_zone(dzone
) {
2380 if (!populated_zone(dzone
))
2384 kfree(zone_pcp(dzone
, cpu
));
2385 zone_pcp(dzone
, cpu
) = NULL
;
2390 static inline void free_zone_pagesets(int cpu
)
2394 for_each_zone(zone
) {
2395 struct per_cpu_pageset
*pset
= zone_pcp(zone
, cpu
);
2397 /* Free per_cpu_pageset if it is slab allocated */
2398 if (pset
!= &boot_pageset
[cpu
])
2400 zone_pcp(zone
, cpu
) = NULL
;
2404 static int __cpuinit
pageset_cpuup_callback(struct notifier_block
*nfb
,
2405 unsigned long action
,
2408 int cpu
= (long)hcpu
;
2409 int ret
= NOTIFY_OK
;
2412 case CPU_UP_PREPARE
:
2413 case CPU_UP_PREPARE_FROZEN
:
2414 if (process_zones(cpu
))
2417 case CPU_UP_CANCELED
:
2418 case CPU_UP_CANCELED_FROZEN
:
2420 case CPU_DEAD_FROZEN
:
2421 free_zone_pagesets(cpu
);
2429 static struct notifier_block __cpuinitdata pageset_notifier
=
2430 { &pageset_cpuup_callback
, NULL
, 0 };
2432 void __init
setup_per_cpu_pageset(void)
2436 /* Initialize per_cpu_pageset for cpu 0.
2437 * A cpuup callback will do this for every cpu
2438 * as it comes online
2440 err
= process_zones(smp_processor_id());
2442 register_cpu_notifier(&pageset_notifier
);
2447 static noinline __init_refok
2448 int zone_wait_table_init(struct zone
*zone
, unsigned long zone_size_pages
)
2451 struct pglist_data
*pgdat
= zone
->zone_pgdat
;
2455 * The per-page waitqueue mechanism uses hashed waitqueues
2458 zone
->wait_table_hash_nr_entries
=
2459 wait_table_hash_nr_entries(zone_size_pages
);
2460 zone
->wait_table_bits
=
2461 wait_table_bits(zone
->wait_table_hash_nr_entries
);
2462 alloc_size
= zone
->wait_table_hash_nr_entries
2463 * sizeof(wait_queue_head_t
);
2465 if (system_state
== SYSTEM_BOOTING
) {
2466 zone
->wait_table
= (wait_queue_head_t
*)
2467 alloc_bootmem_node(pgdat
, alloc_size
);
2470 * This case means that a zone whose size was 0 gets new memory
2471 * via memory hot-add.
2472 * But it may be the case that a new node was hot-added. In
2473 * this case vmalloc() will not be able to use this new node's
2474 * memory - this wait_table must be initialized to use this new
2475 * node itself as well.
2476 * To use this new node's memory, further consideration will be
2479 zone
->wait_table
= vmalloc(alloc_size
);
2481 if (!zone
->wait_table
)
2484 for(i
= 0; i
< zone
->wait_table_hash_nr_entries
; ++i
)
2485 init_waitqueue_head(zone
->wait_table
+ i
);
2490 static __meminit
void zone_pcp_init(struct zone
*zone
)
2493 unsigned long batch
= zone_batchsize(zone
);
2495 for (cpu
= 0; cpu
< NR_CPUS
; cpu
++) {
2497 /* Early boot. Slab allocator not functional yet */
2498 zone_pcp(zone
, cpu
) = &boot_pageset
[cpu
];
2499 setup_pageset(&boot_pageset
[cpu
],0);
2501 setup_pageset(zone_pcp(zone
,cpu
), batch
);
2504 if (zone
->present_pages
)
2505 printk(KERN_DEBUG
" %s zone: %lu pages, LIFO batch:%lu\n",
2506 zone
->name
, zone
->present_pages
, batch
);
2509 __meminit
int init_currently_empty_zone(struct zone
*zone
,
2510 unsigned long zone_start_pfn
,
2512 enum memmap_context context
)
2514 struct pglist_data
*pgdat
= zone
->zone_pgdat
;
2516 ret
= zone_wait_table_init(zone
, size
);
2519 pgdat
->nr_zones
= zone_idx(zone
) + 1;
2521 zone
->zone_start_pfn
= zone_start_pfn
;
2523 memmap_init(size
, pgdat
->node_id
, zone_idx(zone
), zone_start_pfn
);
2525 zone_init_free_lists(pgdat
, zone
, zone
->spanned_pages
);
2530 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
2532 * Basic iterator support. Return the first range of PFNs for a node
2533 * Note: nid == MAX_NUMNODES returns first region regardless of node
2535 static int __meminit
first_active_region_index_in_nid(int nid
)
2539 for (i
= 0; i
< nr_nodemap_entries
; i
++)
2540 if (nid
== MAX_NUMNODES
|| early_node_map
[i
].nid
== nid
)
2547 * Basic iterator support. Return the next active range of PFNs for a node
2548 * Note: nid == MAX_NUMNODES returns next region regardles of node
2550 static int __meminit
next_active_region_index_in_nid(int index
, int nid
)
2552 for (index
= index
+ 1; index
< nr_nodemap_entries
; index
++)
2553 if (nid
== MAX_NUMNODES
|| early_node_map
[index
].nid
== nid
)
2559 #ifndef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
2561 * Required by SPARSEMEM. Given a PFN, return what node the PFN is on.
2562 * Architectures may implement their own version but if add_active_range()
2563 * was used and there are no special requirements, this is a convenient
2566 int __meminit
early_pfn_to_nid(unsigned long pfn
)
2570 for (i
= 0; i
< nr_nodemap_entries
; i
++) {
2571 unsigned long start_pfn
= early_node_map
[i
].start_pfn
;
2572 unsigned long end_pfn
= early_node_map
[i
].end_pfn
;
2574 if (start_pfn
<= pfn
&& pfn
< end_pfn
)
2575 return early_node_map
[i
].nid
;
2580 #endif /* CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID */
2582 /* Basic iterator support to walk early_node_map[] */
2583 #define for_each_active_range_index_in_nid(i, nid) \
2584 for (i = first_active_region_index_in_nid(nid); i != -1; \
2585 i = next_active_region_index_in_nid(i, nid))
2588 * free_bootmem_with_active_regions - Call free_bootmem_node for each active range
2589 * @nid: The node to free memory on. If MAX_NUMNODES, all nodes are freed.
2590 * @max_low_pfn: The highest PFN that will be passed to free_bootmem_node
2592 * If an architecture guarantees that all ranges registered with
2593 * add_active_ranges() contain no holes and may be freed, this
2594 * this function may be used instead of calling free_bootmem() manually.
2596 void __init
free_bootmem_with_active_regions(int nid
,
2597 unsigned long max_low_pfn
)
2601 for_each_active_range_index_in_nid(i
, nid
) {
2602 unsigned long size_pages
= 0;
2603 unsigned long end_pfn
= early_node_map
[i
].end_pfn
;
2605 if (early_node_map
[i
].start_pfn
>= max_low_pfn
)
2608 if (end_pfn
> max_low_pfn
)
2609 end_pfn
= max_low_pfn
;
2611 size_pages
= end_pfn
- early_node_map
[i
].start_pfn
;
2612 free_bootmem_node(NODE_DATA(early_node_map
[i
].nid
),
2613 PFN_PHYS(early_node_map
[i
].start_pfn
),
2614 size_pages
<< PAGE_SHIFT
);
2619 * sparse_memory_present_with_active_regions - Call memory_present for each active range
2620 * @nid: The node to call memory_present for. If MAX_NUMNODES, all nodes will be used.
2622 * If an architecture guarantees that all ranges registered with
2623 * add_active_ranges() contain no holes and may be freed, this
2624 * function may be used instead of calling memory_present() manually.
2626 void __init
sparse_memory_present_with_active_regions(int nid
)
2630 for_each_active_range_index_in_nid(i
, nid
)
2631 memory_present(early_node_map
[i
].nid
,
2632 early_node_map
[i
].start_pfn
,
2633 early_node_map
[i
].end_pfn
);
2637 * push_node_boundaries - Push node boundaries to at least the requested boundary
2638 * @nid: The nid of the node to push the boundary for
2639 * @start_pfn: The start pfn of the node
2640 * @end_pfn: The end pfn of the node
2642 * In reserve-based hot-add, mem_map is allocated that is unused until hotadd
2643 * time. Specifically, on x86_64, SRAT will report ranges that can potentially
2644 * be hotplugged even though no physical memory exists. This function allows
2645 * an arch to push out the node boundaries so mem_map is allocated that can
2648 #ifdef CONFIG_MEMORY_HOTPLUG_RESERVE
2649 void __init
push_node_boundaries(unsigned int nid
,
2650 unsigned long start_pfn
, unsigned long end_pfn
)
2652 printk(KERN_DEBUG
"Entering push_node_boundaries(%u, %lu, %lu)\n",
2653 nid
, start_pfn
, end_pfn
);
2655 /* Initialise the boundary for this node if necessary */
2656 if (node_boundary_end_pfn
[nid
] == 0)
2657 node_boundary_start_pfn
[nid
] = -1UL;
2659 /* Update the boundaries */
2660 if (node_boundary_start_pfn
[nid
] > start_pfn
)
2661 node_boundary_start_pfn
[nid
] = start_pfn
;
2662 if (node_boundary_end_pfn
[nid
] < end_pfn
)
2663 node_boundary_end_pfn
[nid
] = end_pfn
;
2666 /* If necessary, push the node boundary out for reserve hotadd */
2667 static void __meminit
account_node_boundary(unsigned int nid
,
2668 unsigned long *start_pfn
, unsigned long *end_pfn
)
2670 printk(KERN_DEBUG
"Entering account_node_boundary(%u, %lu, %lu)\n",
2671 nid
, *start_pfn
, *end_pfn
);
2673 /* Return if boundary information has not been provided */
2674 if (node_boundary_end_pfn
[nid
] == 0)
2677 /* Check the boundaries and update if necessary */
2678 if (node_boundary_start_pfn
[nid
] < *start_pfn
)
2679 *start_pfn
= node_boundary_start_pfn
[nid
];
2680 if (node_boundary_end_pfn
[nid
] > *end_pfn
)
2681 *end_pfn
= node_boundary_end_pfn
[nid
];
2684 void __init
push_node_boundaries(unsigned int nid
,
2685 unsigned long start_pfn
, unsigned long end_pfn
) {}
2687 static void __meminit
account_node_boundary(unsigned int nid
,
2688 unsigned long *start_pfn
, unsigned long *end_pfn
) {}
2693 * get_pfn_range_for_nid - Return the start and end page frames for a node
2694 * @nid: The nid to return the range for. If MAX_NUMNODES, the min and max PFN are returned.
2695 * @start_pfn: Passed by reference. On return, it will have the node start_pfn.
2696 * @end_pfn: Passed by reference. On return, it will have the node end_pfn.
2698 * It returns the start and end page frame of a node based on information
2699 * provided by an arch calling add_active_range(). If called for a node
2700 * with no available memory, a warning is printed and the start and end
2703 void __meminit
get_pfn_range_for_nid(unsigned int nid
,
2704 unsigned long *start_pfn
, unsigned long *end_pfn
)
2710 for_each_active_range_index_in_nid(i
, nid
) {
2711 *start_pfn
= min(*start_pfn
, early_node_map
[i
].start_pfn
);
2712 *end_pfn
= max(*end_pfn
, early_node_map
[i
].end_pfn
);
2715 if (*start_pfn
== -1UL)
2718 /* Push the node boundaries out if requested */
2719 account_node_boundary(nid
, start_pfn
, end_pfn
);
2723 * This finds a zone that can be used for ZONE_MOVABLE pages. The
2724 * assumption is made that zones within a node are ordered in monotonic
2725 * increasing memory addresses so that the "highest" populated zone is used
2727 void __init
find_usable_zone_for_movable(void)
2730 for (zone_index
= MAX_NR_ZONES
- 1; zone_index
>= 0; zone_index
--) {
2731 if (zone_index
== ZONE_MOVABLE
)
2734 if (arch_zone_highest_possible_pfn
[zone_index
] >
2735 arch_zone_lowest_possible_pfn
[zone_index
])
2739 VM_BUG_ON(zone_index
== -1);
2740 movable_zone
= zone_index
;
2744 * The zone ranges provided by the architecture do not include ZONE_MOVABLE
2745 * because it is sized independant of architecture. Unlike the other zones,
2746 * the starting point for ZONE_MOVABLE is not fixed. It may be different
2747 * in each node depending on the size of each node and how evenly kernelcore
2748 * is distributed. This helper function adjusts the zone ranges
2749 * provided by the architecture for a given node by using the end of the
2750 * highest usable zone for ZONE_MOVABLE. This preserves the assumption that
2751 * zones within a node are in order of monotonic increases memory addresses
2753 void __meminit
adjust_zone_range_for_zone_movable(int nid
,
2754 unsigned long zone_type
,
2755 unsigned long node_start_pfn
,
2756 unsigned long node_end_pfn
,
2757 unsigned long *zone_start_pfn
,
2758 unsigned long *zone_end_pfn
)
2760 /* Only adjust if ZONE_MOVABLE is on this node */
2761 if (zone_movable_pfn
[nid
]) {
2762 /* Size ZONE_MOVABLE */
2763 if (zone_type
== ZONE_MOVABLE
) {
2764 *zone_start_pfn
= zone_movable_pfn
[nid
];
2765 *zone_end_pfn
= min(node_end_pfn
,
2766 arch_zone_highest_possible_pfn
[movable_zone
]);
2768 /* Adjust for ZONE_MOVABLE starting within this range */
2769 } else if (*zone_start_pfn
< zone_movable_pfn
[nid
] &&
2770 *zone_end_pfn
> zone_movable_pfn
[nid
]) {
2771 *zone_end_pfn
= zone_movable_pfn
[nid
];
2773 /* Check if this whole range is within ZONE_MOVABLE */
2774 } else if (*zone_start_pfn
>= zone_movable_pfn
[nid
])
2775 *zone_start_pfn
= *zone_end_pfn
;
2780 * Return the number of pages a zone spans in a node, including holes
2781 * present_pages = zone_spanned_pages_in_node() - zone_absent_pages_in_node()
2783 static unsigned long __meminit
zone_spanned_pages_in_node(int nid
,
2784 unsigned long zone_type
,
2785 unsigned long *ignored
)
2787 unsigned long node_start_pfn
, node_end_pfn
;
2788 unsigned long zone_start_pfn
, zone_end_pfn
;
2790 /* Get the start and end of the node and zone */
2791 get_pfn_range_for_nid(nid
, &node_start_pfn
, &node_end_pfn
);
2792 zone_start_pfn
= arch_zone_lowest_possible_pfn
[zone_type
];
2793 zone_end_pfn
= arch_zone_highest_possible_pfn
[zone_type
];
2794 adjust_zone_range_for_zone_movable(nid
, zone_type
,
2795 node_start_pfn
, node_end_pfn
,
2796 &zone_start_pfn
, &zone_end_pfn
);
2798 /* Check that this node has pages within the zone's required range */
2799 if (zone_end_pfn
< node_start_pfn
|| zone_start_pfn
> node_end_pfn
)
2802 /* Move the zone boundaries inside the node if necessary */
2803 zone_end_pfn
= min(zone_end_pfn
, node_end_pfn
);
2804 zone_start_pfn
= max(zone_start_pfn
, node_start_pfn
);
2806 /* Return the spanned pages */
2807 return zone_end_pfn
- zone_start_pfn
;
2811 * Return the number of holes in a range on a node. If nid is MAX_NUMNODES,
2812 * then all holes in the requested range will be accounted for.
2814 unsigned long __meminit
__absent_pages_in_range(int nid
,
2815 unsigned long range_start_pfn
,
2816 unsigned long range_end_pfn
)
2819 unsigned long prev_end_pfn
= 0, hole_pages
= 0;
2820 unsigned long start_pfn
;
2822 /* Find the end_pfn of the first active range of pfns in the node */
2823 i
= first_active_region_index_in_nid(nid
);
2827 prev_end_pfn
= min(early_node_map
[i
].start_pfn
, range_end_pfn
);
2829 /* Account for ranges before physical memory on this node */
2830 if (early_node_map
[i
].start_pfn
> range_start_pfn
)
2831 hole_pages
= prev_end_pfn
- range_start_pfn
;
2833 /* Find all holes for the zone within the node */
2834 for (; i
!= -1; i
= next_active_region_index_in_nid(i
, nid
)) {
2836 /* No need to continue if prev_end_pfn is outside the zone */
2837 if (prev_end_pfn
>= range_end_pfn
)
2840 /* Make sure the end of the zone is not within the hole */
2841 start_pfn
= min(early_node_map
[i
].start_pfn
, range_end_pfn
);
2842 prev_end_pfn
= max(prev_end_pfn
, range_start_pfn
);
2844 /* Update the hole size cound and move on */
2845 if (start_pfn
> range_start_pfn
) {
2846 BUG_ON(prev_end_pfn
> start_pfn
);
2847 hole_pages
+= start_pfn
- prev_end_pfn
;
2849 prev_end_pfn
= early_node_map
[i
].end_pfn
;
2852 /* Account for ranges past physical memory on this node */
2853 if (range_end_pfn
> prev_end_pfn
)
2854 hole_pages
+= range_end_pfn
-
2855 max(range_start_pfn
, prev_end_pfn
);
2861 * absent_pages_in_range - Return number of page frames in holes within a range
2862 * @start_pfn: The start PFN to start searching for holes
2863 * @end_pfn: The end PFN to stop searching for holes
2865 * It returns the number of pages frames in memory holes within a range.
2867 unsigned long __init
absent_pages_in_range(unsigned long start_pfn
,
2868 unsigned long end_pfn
)
2870 return __absent_pages_in_range(MAX_NUMNODES
, start_pfn
, end_pfn
);
2873 /* Return the number of page frames in holes in a zone on a node */
2874 static unsigned long __meminit
zone_absent_pages_in_node(int nid
,
2875 unsigned long zone_type
,
2876 unsigned long *ignored
)
2878 unsigned long node_start_pfn
, node_end_pfn
;
2879 unsigned long zone_start_pfn
, zone_end_pfn
;
2881 get_pfn_range_for_nid(nid
, &node_start_pfn
, &node_end_pfn
);
2882 zone_start_pfn
= max(arch_zone_lowest_possible_pfn
[zone_type
],
2884 zone_end_pfn
= min(arch_zone_highest_possible_pfn
[zone_type
],
2887 adjust_zone_range_for_zone_movable(nid
, zone_type
,
2888 node_start_pfn
, node_end_pfn
,
2889 &zone_start_pfn
, &zone_end_pfn
);
2890 return __absent_pages_in_range(nid
, zone_start_pfn
, zone_end_pfn
);
2894 static inline unsigned long __meminit
zone_spanned_pages_in_node(int nid
,
2895 unsigned long zone_type
,
2896 unsigned long *zones_size
)
2898 return zones_size
[zone_type
];
2901 static inline unsigned long __meminit
zone_absent_pages_in_node(int nid
,
2902 unsigned long zone_type
,
2903 unsigned long *zholes_size
)
2908 return zholes_size
[zone_type
];
2913 static void __meminit
calculate_node_totalpages(struct pglist_data
*pgdat
,
2914 unsigned long *zones_size
, unsigned long *zholes_size
)
2916 unsigned long realtotalpages
, totalpages
= 0;
2919 for (i
= 0; i
< MAX_NR_ZONES
; i
++)
2920 totalpages
+= zone_spanned_pages_in_node(pgdat
->node_id
, i
,
2922 pgdat
->node_spanned_pages
= totalpages
;
2924 realtotalpages
= totalpages
;
2925 for (i
= 0; i
< MAX_NR_ZONES
; i
++)
2927 zone_absent_pages_in_node(pgdat
->node_id
, i
,
2929 pgdat
->node_present_pages
= realtotalpages
;
2930 printk(KERN_DEBUG
"On node %d totalpages: %lu\n", pgdat
->node_id
,
2935 * Set up the zone data structures:
2936 * - mark all pages reserved
2937 * - mark all memory queues empty
2938 * - clear the memory bitmaps
2940 static void __meminit
free_area_init_core(struct pglist_data
*pgdat
,
2941 unsigned long *zones_size
, unsigned long *zholes_size
)
2944 int nid
= pgdat
->node_id
;
2945 unsigned long zone_start_pfn
= pgdat
->node_start_pfn
;
2948 pgdat_resize_init(pgdat
);
2949 pgdat
->nr_zones
= 0;
2950 init_waitqueue_head(&pgdat
->kswapd_wait
);
2951 pgdat
->kswapd_max_order
= 0;
2953 for (j
= 0; j
< MAX_NR_ZONES
; j
++) {
2954 struct zone
*zone
= pgdat
->node_zones
+ j
;
2955 unsigned long size
, realsize
, memmap_pages
;
2957 size
= zone_spanned_pages_in_node(nid
, j
, zones_size
);
2958 realsize
= size
- zone_absent_pages_in_node(nid
, j
,
2962 * Adjust realsize so that it accounts for how much memory
2963 * is used by this zone for memmap. This affects the watermark
2964 * and per-cpu initialisations
2966 memmap_pages
= (size
* sizeof(struct page
)) >> PAGE_SHIFT
;
2967 if (realsize
>= memmap_pages
) {
2968 realsize
-= memmap_pages
;
2970 " %s zone: %lu pages used for memmap\n",
2971 zone_names
[j
], memmap_pages
);
2974 " %s zone: %lu pages exceeds realsize %lu\n",
2975 zone_names
[j
], memmap_pages
, realsize
);
2977 /* Account for reserved pages */
2978 if (j
== 0 && realsize
> dma_reserve
) {
2979 realsize
-= dma_reserve
;
2980 printk(KERN_DEBUG
" %s zone: %lu pages reserved\n",
2981 zone_names
[0], dma_reserve
);
2984 if (!is_highmem_idx(j
))
2985 nr_kernel_pages
+= realsize
;
2986 nr_all_pages
+= realsize
;
2988 zone
->spanned_pages
= size
;
2989 zone
->present_pages
= realsize
;
2992 zone
->min_unmapped_pages
= (realsize
*sysctl_min_unmapped_ratio
)
2994 zone
->min_slab_pages
= (realsize
* sysctl_min_slab_ratio
) / 100;
2996 zone
->name
= zone_names
[j
];
2997 spin_lock_init(&zone
->lock
);
2998 spin_lock_init(&zone
->lru_lock
);
2999 zone_seqlock_init(zone
);
3000 zone
->zone_pgdat
= pgdat
;
3002 zone
->prev_priority
= DEF_PRIORITY
;
3004 zone_pcp_init(zone
);
3005 INIT_LIST_HEAD(&zone
->active_list
);
3006 INIT_LIST_HEAD(&zone
->inactive_list
);
3007 zone
->nr_scan_active
= 0;
3008 zone
->nr_scan_inactive
= 0;
3009 zap_zone_vm_stats(zone
);
3010 atomic_set(&zone
->reclaim_in_progress
, 0);
3014 ret
= init_currently_empty_zone(zone
, zone_start_pfn
,
3015 size
, MEMMAP_EARLY
);
3017 zone_start_pfn
+= size
;
3021 static void __init_refok
alloc_node_mem_map(struct pglist_data
*pgdat
)
3023 /* Skip empty nodes */
3024 if (!pgdat
->node_spanned_pages
)
3027 #ifdef CONFIG_FLAT_NODE_MEM_MAP
3028 /* ia64 gets its own node_mem_map, before this, without bootmem */
3029 if (!pgdat
->node_mem_map
) {
3030 unsigned long size
, start
, end
;
3034 * The zone's endpoints aren't required to be MAX_ORDER
3035 * aligned but the node_mem_map endpoints must be in order
3036 * for the buddy allocator to function correctly.
3038 start
= pgdat
->node_start_pfn
& ~(MAX_ORDER_NR_PAGES
- 1);
3039 end
= pgdat
->node_start_pfn
+ pgdat
->node_spanned_pages
;
3040 end
= ALIGN(end
, MAX_ORDER_NR_PAGES
);
3041 size
= (end
- start
) * sizeof(struct page
);
3042 map
= alloc_remap(pgdat
->node_id
, size
);
3044 map
= alloc_bootmem_node(pgdat
, size
);
3045 pgdat
->node_mem_map
= map
+ (pgdat
->node_start_pfn
- start
);
3047 #ifndef CONFIG_NEED_MULTIPLE_NODES
3049 * With no DISCONTIG, the global mem_map is just set as node 0's
3051 if (pgdat
== NODE_DATA(0)) {
3052 mem_map
= NODE_DATA(0)->node_mem_map
;
3053 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
3054 if (page_to_pfn(mem_map
) != pgdat
->node_start_pfn
)
3055 mem_map
-= pgdat
->node_start_pfn
;
3056 #endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
3059 #endif /* CONFIG_FLAT_NODE_MEM_MAP */
3062 void __meminit
free_area_init_node(int nid
, struct pglist_data
*pgdat
,
3063 unsigned long *zones_size
, unsigned long node_start_pfn
,
3064 unsigned long *zholes_size
)
3066 pgdat
->node_id
= nid
;
3067 pgdat
->node_start_pfn
= node_start_pfn
;
3068 calculate_node_totalpages(pgdat
, zones_size
, zholes_size
);
3070 alloc_node_mem_map(pgdat
);
3072 free_area_init_core(pgdat
, zones_size
, zholes_size
);
3075 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
3077 #if MAX_NUMNODES > 1
3079 * Figure out the number of possible node ids.
3081 static void __init
setup_nr_node_ids(void)
3084 unsigned int highest
= 0;
3086 for_each_node_mask(node
, node_possible_map
)
3088 nr_node_ids
= highest
+ 1;
3091 static inline void setup_nr_node_ids(void)
3097 * add_active_range - Register a range of PFNs backed by physical memory
3098 * @nid: The node ID the range resides on
3099 * @start_pfn: The start PFN of the available physical memory
3100 * @end_pfn: The end PFN of the available physical memory
3102 * These ranges are stored in an early_node_map[] and later used by
3103 * free_area_init_nodes() to calculate zone sizes and holes. If the
3104 * range spans a memory hole, it is up to the architecture to ensure
3105 * the memory is not freed by the bootmem allocator. If possible
3106 * the range being registered will be merged with existing ranges.
3108 void __init
add_active_range(unsigned int nid
, unsigned long start_pfn
,
3109 unsigned long end_pfn
)
3113 printk(KERN_DEBUG
"Entering add_active_range(%d, %lu, %lu) "
3114 "%d entries of %d used\n",
3115 nid
, start_pfn
, end_pfn
,
3116 nr_nodemap_entries
, MAX_ACTIVE_REGIONS
);
3118 /* Merge with existing active regions if possible */
3119 for (i
= 0; i
< nr_nodemap_entries
; i
++) {
3120 if (early_node_map
[i
].nid
!= nid
)
3123 /* Skip if an existing region covers this new one */
3124 if (start_pfn
>= early_node_map
[i
].start_pfn
&&
3125 end_pfn
<= early_node_map
[i
].end_pfn
)
3128 /* Merge forward if suitable */
3129 if (start_pfn
<= early_node_map
[i
].end_pfn
&&
3130 end_pfn
> early_node_map
[i
].end_pfn
) {
3131 early_node_map
[i
].end_pfn
= end_pfn
;
3135 /* Merge backward if suitable */
3136 if (start_pfn
< early_node_map
[i
].end_pfn
&&
3137 end_pfn
>= early_node_map
[i
].start_pfn
) {
3138 early_node_map
[i
].start_pfn
= start_pfn
;
3143 /* Check that early_node_map is large enough */
3144 if (i
>= MAX_ACTIVE_REGIONS
) {
3145 printk(KERN_CRIT
"More than %d memory regions, truncating\n",
3146 MAX_ACTIVE_REGIONS
);
3150 early_node_map
[i
].nid
= nid
;
3151 early_node_map
[i
].start_pfn
= start_pfn
;
3152 early_node_map
[i
].end_pfn
= end_pfn
;
3153 nr_nodemap_entries
= i
+ 1;
3157 * shrink_active_range - Shrink an existing registered range of PFNs
3158 * @nid: The node id the range is on that should be shrunk
3159 * @old_end_pfn: The old end PFN of the range
3160 * @new_end_pfn: The new PFN of the range
3162 * i386 with NUMA use alloc_remap() to store a node_mem_map on a local node.
3163 * The map is kept at the end physical page range that has already been
3164 * registered with add_active_range(). This function allows an arch to shrink
3165 * an existing registered range.
3167 void __init
shrink_active_range(unsigned int nid
, unsigned long old_end_pfn
,
3168 unsigned long new_end_pfn
)
3172 /* Find the old active region end and shrink */
3173 for_each_active_range_index_in_nid(i
, nid
)
3174 if (early_node_map
[i
].end_pfn
== old_end_pfn
) {
3175 early_node_map
[i
].end_pfn
= new_end_pfn
;
3181 * remove_all_active_ranges - Remove all currently registered regions
3183 * During discovery, it may be found that a table like SRAT is invalid
3184 * and an alternative discovery method must be used. This function removes
3185 * all currently registered regions.
3187 void __init
remove_all_active_ranges(void)
3189 memset(early_node_map
, 0, sizeof(early_node_map
));
3190 nr_nodemap_entries
= 0;
3191 #ifdef CONFIG_MEMORY_HOTPLUG_RESERVE
3192 memset(node_boundary_start_pfn
, 0, sizeof(node_boundary_start_pfn
));
3193 memset(node_boundary_end_pfn
, 0, sizeof(node_boundary_end_pfn
));
3194 #endif /* CONFIG_MEMORY_HOTPLUG_RESERVE */
3197 /* Compare two active node_active_regions */
3198 static int __init
cmp_node_active_region(const void *a
, const void *b
)
3200 struct node_active_region
*arange
= (struct node_active_region
*)a
;
3201 struct node_active_region
*brange
= (struct node_active_region
*)b
;
3203 /* Done this way to avoid overflows */
3204 if (arange
->start_pfn
> brange
->start_pfn
)
3206 if (arange
->start_pfn
< brange
->start_pfn
)
3212 /* sort the node_map by start_pfn */
3213 static void __init
sort_node_map(void)
3215 sort(early_node_map
, (size_t)nr_nodemap_entries
,
3216 sizeof(struct node_active_region
),
3217 cmp_node_active_region
, NULL
);
3220 /* Find the lowest pfn for a node */
3221 unsigned long __init
find_min_pfn_for_node(unsigned long nid
)
3224 unsigned long min_pfn
= ULONG_MAX
;
3226 /* Assuming a sorted map, the first range found has the starting pfn */
3227 for_each_active_range_index_in_nid(i
, nid
)
3228 min_pfn
= min(min_pfn
, early_node_map
[i
].start_pfn
);
3230 if (min_pfn
== ULONG_MAX
) {
3232 "Could not find start_pfn for node %lu\n", nid
);
3240 * find_min_pfn_with_active_regions - Find the minimum PFN registered
3242 * It returns the minimum PFN based on information provided via
3243 * add_active_range().
3245 unsigned long __init
find_min_pfn_with_active_regions(void)
3247 return find_min_pfn_for_node(MAX_NUMNODES
);
3251 * find_max_pfn_with_active_regions - Find the maximum PFN registered
3253 * It returns the maximum PFN based on information provided via
3254 * add_active_range().
3256 unsigned long __init
find_max_pfn_with_active_regions(void)
3259 unsigned long max_pfn
= 0;
3261 for (i
= 0; i
< nr_nodemap_entries
; i
++)
3262 max_pfn
= max(max_pfn
, early_node_map
[i
].end_pfn
);
3267 unsigned long __init
early_calculate_totalpages(void)
3270 unsigned long totalpages
= 0;
3272 for (i
= 0; i
< nr_nodemap_entries
; i
++)
3273 totalpages
+= early_node_map
[i
].end_pfn
-
3274 early_node_map
[i
].start_pfn
;
3280 * Find the PFN the Movable zone begins in each node. Kernel memory
3281 * is spread evenly between nodes as long as the nodes have enough
3282 * memory. When they don't, some nodes will have more kernelcore than
3285 void __init
find_zone_movable_pfns_for_nodes(unsigned long *movable_pfn
)
3288 unsigned long usable_startpfn
;
3289 unsigned long kernelcore_node
, kernelcore_remaining
;
3290 int usable_nodes
= num_online_nodes();
3293 * If movablecore was specified, calculate what size of
3294 * kernelcore that corresponds so that memory usable for
3295 * any allocation type is evenly spread. If both kernelcore
3296 * and movablecore are specified, then the value of kernelcore
3297 * will be used for required_kernelcore if it's greater than
3298 * what movablecore would have allowed.
3300 if (required_movablecore
) {
3301 unsigned long totalpages
= early_calculate_totalpages();
3302 unsigned long corepages
;
3305 * Round-up so that ZONE_MOVABLE is at least as large as what
3306 * was requested by the user
3308 required_movablecore
=
3309 roundup(required_movablecore
, MAX_ORDER_NR_PAGES
);
3310 corepages
= totalpages
- required_movablecore
;
3312 required_kernelcore
= max(required_kernelcore
, corepages
);
3315 /* If kernelcore was not specified, there is no ZONE_MOVABLE */
3316 if (!required_kernelcore
)
3319 /* usable_startpfn is the lowest possible pfn ZONE_MOVABLE can be at */
3320 find_usable_zone_for_movable();
3321 usable_startpfn
= arch_zone_lowest_possible_pfn
[movable_zone
];
3324 /* Spread kernelcore memory as evenly as possible throughout nodes */
3325 kernelcore_node
= required_kernelcore
/ usable_nodes
;
3326 for_each_online_node(nid
) {
3328 * Recalculate kernelcore_node if the division per node
3329 * now exceeds what is necessary to satisfy the requested
3330 * amount of memory for the kernel
3332 if (required_kernelcore
< kernelcore_node
)
3333 kernelcore_node
= required_kernelcore
/ usable_nodes
;
3336 * As the map is walked, we track how much memory is usable
3337 * by the kernel using kernelcore_remaining. When it is
3338 * 0, the rest of the node is usable by ZONE_MOVABLE
3340 kernelcore_remaining
= kernelcore_node
;
3342 /* Go through each range of PFNs within this node */
3343 for_each_active_range_index_in_nid(i
, nid
) {
3344 unsigned long start_pfn
, end_pfn
;
3345 unsigned long size_pages
;
3347 start_pfn
= max(early_node_map
[i
].start_pfn
,
3348 zone_movable_pfn
[nid
]);
3349 end_pfn
= early_node_map
[i
].end_pfn
;
3350 if (start_pfn
>= end_pfn
)
3353 /* Account for what is only usable for kernelcore */
3354 if (start_pfn
< usable_startpfn
) {
3355 unsigned long kernel_pages
;
3356 kernel_pages
= min(end_pfn
, usable_startpfn
)
3359 kernelcore_remaining
-= min(kernel_pages
,
3360 kernelcore_remaining
);
3361 required_kernelcore
-= min(kernel_pages
,
3362 required_kernelcore
);
3364 /* Continue if range is now fully accounted */
3365 if (end_pfn
<= usable_startpfn
) {
3368 * Push zone_movable_pfn to the end so
3369 * that if we have to rebalance
3370 * kernelcore across nodes, we will
3371 * not double account here
3373 zone_movable_pfn
[nid
] = end_pfn
;
3376 start_pfn
= usable_startpfn
;
3380 * The usable PFN range for ZONE_MOVABLE is from
3381 * start_pfn->end_pfn. Calculate size_pages as the
3382 * number of pages used as kernelcore
3384 size_pages
= end_pfn
- start_pfn
;
3385 if (size_pages
> kernelcore_remaining
)
3386 size_pages
= kernelcore_remaining
;
3387 zone_movable_pfn
[nid
] = start_pfn
+ size_pages
;
3390 * Some kernelcore has been met, update counts and
3391 * break if the kernelcore for this node has been
3394 required_kernelcore
-= min(required_kernelcore
,
3396 kernelcore_remaining
-= size_pages
;
3397 if (!kernelcore_remaining
)
3403 * If there is still required_kernelcore, we do another pass with one
3404 * less node in the count. This will push zone_movable_pfn[nid] further
3405 * along on the nodes that still have memory until kernelcore is
3409 if (usable_nodes
&& required_kernelcore
> usable_nodes
)
3412 /* Align start of ZONE_MOVABLE on all nids to MAX_ORDER_NR_PAGES */
3413 for (nid
= 0; nid
< MAX_NUMNODES
; nid
++)
3414 zone_movable_pfn
[nid
] =
3415 roundup(zone_movable_pfn
[nid
], MAX_ORDER_NR_PAGES
);
3419 * free_area_init_nodes - Initialise all pg_data_t and zone data
3420 * @max_zone_pfn: an array of max PFNs for each zone
3422 * This will call free_area_init_node() for each active node in the system.
3423 * Using the page ranges provided by add_active_range(), the size of each
3424 * zone in each node and their holes is calculated. If the maximum PFN
3425 * between two adjacent zones match, it is assumed that the zone is empty.
3426 * For example, if arch_max_dma_pfn == arch_max_dma32_pfn, it is assumed
3427 * that arch_max_dma32_pfn has no pages. It is also assumed that a zone
3428 * starts where the previous one ended. For example, ZONE_DMA32 starts
3429 * at arch_max_dma_pfn.
3431 void __init
free_area_init_nodes(unsigned long *max_zone_pfn
)
3436 /* Sort early_node_map as initialisation assumes it is sorted */
3439 /* Record where the zone boundaries are */
3440 memset(arch_zone_lowest_possible_pfn
, 0,
3441 sizeof(arch_zone_lowest_possible_pfn
));
3442 memset(arch_zone_highest_possible_pfn
, 0,
3443 sizeof(arch_zone_highest_possible_pfn
));
3444 arch_zone_lowest_possible_pfn
[0] = find_min_pfn_with_active_regions();
3445 arch_zone_highest_possible_pfn
[0] = max_zone_pfn
[0];
3446 for (i
= 1; i
< MAX_NR_ZONES
; i
++) {
3447 if (i
== ZONE_MOVABLE
)
3449 arch_zone_lowest_possible_pfn
[i
] =
3450 arch_zone_highest_possible_pfn
[i
-1];
3451 arch_zone_highest_possible_pfn
[i
] =
3452 max(max_zone_pfn
[i
], arch_zone_lowest_possible_pfn
[i
]);
3454 arch_zone_lowest_possible_pfn
[ZONE_MOVABLE
] = 0;
3455 arch_zone_highest_possible_pfn
[ZONE_MOVABLE
] = 0;
3457 /* Find the PFNs that ZONE_MOVABLE begins at in each node */
3458 memset(zone_movable_pfn
, 0, sizeof(zone_movable_pfn
));
3459 find_zone_movable_pfns_for_nodes(zone_movable_pfn
);
3461 /* Print out the zone ranges */
3462 printk("Zone PFN ranges:\n");
3463 for (i
= 0; i
< MAX_NR_ZONES
; i
++) {
3464 if (i
== ZONE_MOVABLE
)
3466 printk(" %-8s %8lu -> %8lu\n",
3468 arch_zone_lowest_possible_pfn
[i
],
3469 arch_zone_highest_possible_pfn
[i
]);
3472 /* Print out the PFNs ZONE_MOVABLE begins at in each node */
3473 printk("Movable zone start PFN for each node\n");
3474 for (i
= 0; i
< MAX_NUMNODES
; i
++) {
3475 if (zone_movable_pfn
[i
])
3476 printk(" Node %d: %lu\n", i
, zone_movable_pfn
[i
]);
3479 /* Print out the early_node_map[] */
3480 printk("early_node_map[%d] active PFN ranges\n", nr_nodemap_entries
);
3481 for (i
= 0; i
< nr_nodemap_entries
; i
++)
3482 printk(" %3d: %8lu -> %8lu\n", early_node_map
[i
].nid
,
3483 early_node_map
[i
].start_pfn
,
3484 early_node_map
[i
].end_pfn
);
3486 /* Initialise every node */
3487 setup_nr_node_ids();
3488 for_each_online_node(nid
) {
3489 pg_data_t
*pgdat
= NODE_DATA(nid
);
3490 free_area_init_node(nid
, pgdat
, NULL
,
3491 find_min_pfn_for_node(nid
), NULL
);
3495 static int __init
cmdline_parse_core(char *p
, unsigned long *core
)
3497 unsigned long long coremem
;
3501 coremem
= memparse(p
, &p
);
3502 *core
= coremem
>> PAGE_SHIFT
;
3504 /* Paranoid check that UL is enough for the coremem value */
3505 WARN_ON((coremem
>> PAGE_SHIFT
) > ULONG_MAX
);
3511 * kernelcore=size sets the amount of memory for use for allocations that
3512 * cannot be reclaimed or migrated.
3514 static int __init
cmdline_parse_kernelcore(char *p
)
3516 return cmdline_parse_core(p
, &required_kernelcore
);
3520 * movablecore=size sets the amount of memory for use for allocations that
3521 * can be reclaimed or migrated.
3523 static int __init
cmdline_parse_movablecore(char *p
)
3525 return cmdline_parse_core(p
, &required_movablecore
);
3528 early_param("kernelcore", cmdline_parse_kernelcore
);
3529 early_param("movablecore", cmdline_parse_movablecore
);
3531 #endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
3534 * set_dma_reserve - set the specified number of pages reserved in the first zone
3535 * @new_dma_reserve: The number of pages to mark reserved
3537 * The per-cpu batchsize and zone watermarks are determined by present_pages.
3538 * In the DMA zone, a significant percentage may be consumed by kernel image
3539 * and other unfreeable allocations which can skew the watermarks badly. This
3540 * function may optionally be used to account for unfreeable pages in the
3541 * first zone (e.g., ZONE_DMA). The effect will be lower watermarks and
3542 * smaller per-cpu batchsize.
3544 void __init
set_dma_reserve(unsigned long new_dma_reserve
)
3546 dma_reserve
= new_dma_reserve
;
3549 #ifndef CONFIG_NEED_MULTIPLE_NODES
3550 static bootmem_data_t contig_bootmem_data
;
3551 struct pglist_data contig_page_data
= { .bdata
= &contig_bootmem_data
};
3553 EXPORT_SYMBOL(contig_page_data
);
3556 void __init
free_area_init(unsigned long *zones_size
)
3558 free_area_init_node(0, NODE_DATA(0), zones_size
,
3559 __pa(PAGE_OFFSET
) >> PAGE_SHIFT
, NULL
);
3562 static int page_alloc_cpu_notify(struct notifier_block
*self
,
3563 unsigned long action
, void *hcpu
)
3565 int cpu
= (unsigned long)hcpu
;
3567 if (action
== CPU_DEAD
|| action
== CPU_DEAD_FROZEN
) {
3568 local_irq_disable();
3570 vm_events_fold_cpu(cpu
);
3572 refresh_cpu_vm_stats(cpu
);
3577 void __init
page_alloc_init(void)
3579 hotcpu_notifier(page_alloc_cpu_notify
, 0);
3583 * calculate_totalreserve_pages - called when sysctl_lower_zone_reserve_ratio
3584 * or min_free_kbytes changes.
3586 static void calculate_totalreserve_pages(void)
3588 struct pglist_data
*pgdat
;
3589 unsigned long reserve_pages
= 0;
3590 enum zone_type i
, j
;
3592 for_each_online_pgdat(pgdat
) {
3593 for (i
= 0; i
< MAX_NR_ZONES
; i
++) {
3594 struct zone
*zone
= pgdat
->node_zones
+ i
;
3595 unsigned long max
= 0;
3597 /* Find valid and maximum lowmem_reserve in the zone */
3598 for (j
= i
; j
< MAX_NR_ZONES
; j
++) {
3599 if (zone
->lowmem_reserve
[j
] > max
)
3600 max
= zone
->lowmem_reserve
[j
];
3603 /* we treat pages_high as reserved pages. */
3604 max
+= zone
->pages_high
;
3606 if (max
> zone
->present_pages
)
3607 max
= zone
->present_pages
;
3608 reserve_pages
+= max
;
3611 totalreserve_pages
= reserve_pages
;
3615 * setup_per_zone_lowmem_reserve - called whenever
3616 * sysctl_lower_zone_reserve_ratio changes. Ensures that each zone
3617 * has a correct pages reserved value, so an adequate number of
3618 * pages are left in the zone after a successful __alloc_pages().
3620 static void setup_per_zone_lowmem_reserve(void)
3622 struct pglist_data
*pgdat
;
3623 enum zone_type j
, idx
;
3625 for_each_online_pgdat(pgdat
) {
3626 for (j
= 0; j
< MAX_NR_ZONES
; j
++) {
3627 struct zone
*zone
= pgdat
->node_zones
+ j
;
3628 unsigned long present_pages
= zone
->present_pages
;
3630 zone
->lowmem_reserve
[j
] = 0;
3634 struct zone
*lower_zone
;
3638 if (sysctl_lowmem_reserve_ratio
[idx
] < 1)
3639 sysctl_lowmem_reserve_ratio
[idx
] = 1;
3641 lower_zone
= pgdat
->node_zones
+ idx
;
3642 lower_zone
->lowmem_reserve
[j
] = present_pages
/
3643 sysctl_lowmem_reserve_ratio
[idx
];
3644 present_pages
+= lower_zone
->present_pages
;
3649 /* update totalreserve_pages */
3650 calculate_totalreserve_pages();
3654 * setup_per_zone_pages_min - called when min_free_kbytes changes.
3656 * Ensures that the pages_{min,low,high} values for each zone are set correctly
3657 * with respect to min_free_kbytes.
3659 void setup_per_zone_pages_min(void)
3661 unsigned long pages_min
= min_free_kbytes
>> (PAGE_SHIFT
- 10);
3662 unsigned long lowmem_pages
= 0;
3664 unsigned long flags
;
3666 /* Calculate total number of !ZONE_HIGHMEM pages */
3667 for_each_zone(zone
) {
3668 if (!is_highmem(zone
))
3669 lowmem_pages
+= zone
->present_pages
;
3672 for_each_zone(zone
) {
3675 spin_lock_irqsave(&zone
->lru_lock
, flags
);
3676 tmp
= (u64
)pages_min
* zone
->present_pages
;
3677 do_div(tmp
, lowmem_pages
);
3678 if (is_highmem(zone
)) {
3680 * __GFP_HIGH and PF_MEMALLOC allocations usually don't
3681 * need highmem pages, so cap pages_min to a small
3684 * The (pages_high-pages_low) and (pages_low-pages_min)
3685 * deltas controls asynch page reclaim, and so should
3686 * not be capped for highmem.
3690 min_pages
= zone
->present_pages
/ 1024;
3691 if (min_pages
< SWAP_CLUSTER_MAX
)
3692 min_pages
= SWAP_CLUSTER_MAX
;
3693 if (min_pages
> 128)
3695 zone
->pages_min
= min_pages
;
3698 * If it's a lowmem zone, reserve a number of pages
3699 * proportionate to the zone's size.
3701 zone
->pages_min
= tmp
;
3704 zone
->pages_low
= zone
->pages_min
+ (tmp
>> 2);
3705 zone
->pages_high
= zone
->pages_min
+ (tmp
>> 1);
3706 spin_unlock_irqrestore(&zone
->lru_lock
, flags
);
3709 /* update totalreserve_pages */
3710 calculate_totalreserve_pages();
3714 * Initialise min_free_kbytes.
3716 * For small machines we want it small (128k min). For large machines
3717 * we want it large (64MB max). But it is not linear, because network
3718 * bandwidth does not increase linearly with machine size. We use
3720 * min_free_kbytes = 4 * sqrt(lowmem_kbytes), for better accuracy:
3721 * min_free_kbytes = sqrt(lowmem_kbytes * 16)
3737 static int __init
init_per_zone_pages_min(void)
3739 unsigned long lowmem_kbytes
;
3741 lowmem_kbytes
= nr_free_buffer_pages() * (PAGE_SIZE
>> 10);
3743 min_free_kbytes
= int_sqrt(lowmem_kbytes
* 16);
3744 if (min_free_kbytes
< 128)
3745 min_free_kbytes
= 128;
3746 if (min_free_kbytes
> 65536)
3747 min_free_kbytes
= 65536;
3748 setup_per_zone_pages_min();
3749 setup_per_zone_lowmem_reserve();
3752 module_init(init_per_zone_pages_min
)
3755 * min_free_kbytes_sysctl_handler - just a wrapper around proc_dointvec() so
3756 * that we can call two helper functions whenever min_free_kbytes
3759 int min_free_kbytes_sysctl_handler(ctl_table
*table
, int write
,
3760 struct file
*file
, void __user
*buffer
, size_t *length
, loff_t
*ppos
)
3762 proc_dointvec(table
, write
, file
, buffer
, length
, ppos
);
3764 setup_per_zone_pages_min();
3769 int sysctl_min_unmapped_ratio_sysctl_handler(ctl_table
*table
, int write
,
3770 struct file
*file
, void __user
*buffer
, size_t *length
, loff_t
*ppos
)
3775 rc
= proc_dointvec_minmax(table
, write
, file
, buffer
, length
, ppos
);
3780 zone
->min_unmapped_pages
= (zone
->present_pages
*
3781 sysctl_min_unmapped_ratio
) / 100;
3785 int sysctl_min_slab_ratio_sysctl_handler(ctl_table
*table
, int write
,
3786 struct file
*file
, void __user
*buffer
, size_t *length
, loff_t
*ppos
)
3791 rc
= proc_dointvec_minmax(table
, write
, file
, buffer
, length
, ppos
);
3796 zone
->min_slab_pages
= (zone
->present_pages
*
3797 sysctl_min_slab_ratio
) / 100;
3803 * lowmem_reserve_ratio_sysctl_handler - just a wrapper around
3804 * proc_dointvec() so that we can call setup_per_zone_lowmem_reserve()
3805 * whenever sysctl_lowmem_reserve_ratio changes.
3807 * The reserve ratio obviously has absolutely no relation with the
3808 * pages_min watermarks. The lowmem reserve ratio can only make sense
3809 * if in function of the boot time zone sizes.
3811 int lowmem_reserve_ratio_sysctl_handler(ctl_table
*table
, int write
,
3812 struct file
*file
, void __user
*buffer
, size_t *length
, loff_t
*ppos
)
3814 proc_dointvec_minmax(table
, write
, file
, buffer
, length
, ppos
);
3815 setup_per_zone_lowmem_reserve();
3820 * percpu_pagelist_fraction - changes the pcp->high for each zone on each
3821 * cpu. It is the fraction of total pages in each zone that a hot per cpu pagelist
3822 * can have before it gets flushed back to buddy allocator.
3825 int percpu_pagelist_fraction_sysctl_handler(ctl_table
*table
, int write
,
3826 struct file
*file
, void __user
*buffer
, size_t *length
, loff_t
*ppos
)
3832 ret
= proc_dointvec_minmax(table
, write
, file
, buffer
, length
, ppos
);
3833 if (!write
|| (ret
== -EINVAL
))
3835 for_each_zone(zone
) {
3836 for_each_online_cpu(cpu
) {
3838 high
= zone
->present_pages
/ percpu_pagelist_fraction
;
3839 setup_pagelist_highmark(zone_pcp(zone
, cpu
), high
);
3845 int hashdist
= HASHDIST_DEFAULT
;
3848 static int __init
set_hashdist(char *str
)
3852 hashdist
= simple_strtoul(str
, &str
, 0);
3855 __setup("hashdist=", set_hashdist
);
3859 * allocate a large system hash table from bootmem
3860 * - it is assumed that the hash table must contain an exact power-of-2
3861 * quantity of entries
3862 * - limit is the number of hash buckets, not the total allocation size
3864 void *__init
alloc_large_system_hash(const char *tablename
,
3865 unsigned long bucketsize
,
3866 unsigned long numentries
,
3869 unsigned int *_hash_shift
,
3870 unsigned int *_hash_mask
,
3871 unsigned long limit
)
3873 unsigned long long max
= limit
;
3874 unsigned long log2qty
, size
;
3877 /* allow the kernel cmdline to have a say */
3879 /* round applicable memory size up to nearest megabyte */
3880 numentries
= nr_kernel_pages
;
3881 numentries
+= (1UL << (20 - PAGE_SHIFT
)) - 1;
3882 numentries
>>= 20 - PAGE_SHIFT
;
3883 numentries
<<= 20 - PAGE_SHIFT
;
3885 /* limit to 1 bucket per 2^scale bytes of low memory */
3886 if (scale
> PAGE_SHIFT
)
3887 numentries
>>= (scale
- PAGE_SHIFT
);
3889 numentries
<<= (PAGE_SHIFT
- scale
);
3891 /* Make sure we've got at least a 0-order allocation.. */
3892 if (unlikely((numentries
* bucketsize
) < PAGE_SIZE
))
3893 numentries
= PAGE_SIZE
/ bucketsize
;
3895 numentries
= roundup_pow_of_two(numentries
);
3897 /* limit allocation size to 1/16 total memory by default */
3899 max
= ((unsigned long long)nr_all_pages
<< PAGE_SHIFT
) >> 4;
3900 do_div(max
, bucketsize
);
3903 if (numentries
> max
)
3906 log2qty
= ilog2(numentries
);
3909 size
= bucketsize
<< log2qty
;
3910 if (flags
& HASH_EARLY
)
3911 table
= alloc_bootmem(size
);
3913 table
= __vmalloc(size
, GFP_ATOMIC
, PAGE_KERNEL
);
3915 unsigned long order
;
3916 for (order
= 0; ((1UL << order
) << PAGE_SHIFT
) < size
; order
++)
3918 table
= (void*) __get_free_pages(GFP_ATOMIC
, order
);
3920 * If bucketsize is not a power-of-two, we may free
3921 * some pages at the end of hash table.
3924 unsigned long alloc_end
= (unsigned long)table
+
3925 (PAGE_SIZE
<< order
);
3926 unsigned long used
= (unsigned long)table
+
3928 split_page(virt_to_page(table
), order
);
3929 while (used
< alloc_end
) {
3935 } while (!table
&& size
> PAGE_SIZE
&& --log2qty
);
3938 panic("Failed to allocate %s hash table\n", tablename
);
3940 printk(KERN_INFO
"%s hash table entries: %d (order: %d, %lu bytes)\n",
3943 ilog2(size
) - PAGE_SHIFT
,
3947 *_hash_shift
= log2qty
;
3949 *_hash_mask
= (1 << log2qty
) - 1;
3954 #ifdef CONFIG_OUT_OF_LINE_PFN_TO_PAGE
3955 struct page
*pfn_to_page(unsigned long pfn
)
3957 return __pfn_to_page(pfn
);
3959 unsigned long page_to_pfn(struct page
*page
)
3961 return __page_to_pfn(page
);
3963 EXPORT_SYMBOL(pfn_to_page
);
3964 EXPORT_SYMBOL(page_to_pfn
);
3965 #endif /* CONFIG_OUT_OF_LINE_PFN_TO_PAGE */