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 /* return values int ....just for stop_machine_run() */
2084 static int __build_all_zonelists(void *dummy
)
2088 for_each_online_node(nid
) {
2089 build_zonelists(NODE_DATA(nid
));
2090 build_zonelist_cache(NODE_DATA(nid
));
2095 void build_all_zonelists(void)
2097 set_zonelist_order();
2099 if (system_state
== SYSTEM_BOOTING
) {
2100 __build_all_zonelists(NULL
);
2101 cpuset_init_current_mems_allowed();
2103 /* we have to stop all cpus to guaranntee there is no user
2105 stop_machine_run(__build_all_zonelists
, NULL
, NR_CPUS
);
2106 /* cpuset refresh routine should be here */
2108 vm_total_pages
= nr_free_pagecache_pages();
2109 printk("Built %i zonelists in %s order. Total pages: %ld\n",
2111 zonelist_order_name
[current_zonelist_order
],
2114 printk("Policy zone: %s\n", zone_names
[policy_zone
]);
2119 * Helper functions to size the waitqueue hash table.
2120 * Essentially these want to choose hash table sizes sufficiently
2121 * large so that collisions trying to wait on pages are rare.
2122 * But in fact, the number of active page waitqueues on typical
2123 * systems is ridiculously low, less than 200. So this is even
2124 * conservative, even though it seems large.
2126 * The constant PAGES_PER_WAITQUEUE specifies the ratio of pages to
2127 * waitqueues, i.e. the size of the waitq table given the number of pages.
2129 #define PAGES_PER_WAITQUEUE 256
2131 #ifndef CONFIG_MEMORY_HOTPLUG
2132 static inline unsigned long wait_table_hash_nr_entries(unsigned long pages
)
2134 unsigned long size
= 1;
2136 pages
/= PAGES_PER_WAITQUEUE
;
2138 while (size
< pages
)
2142 * Once we have dozens or even hundreds of threads sleeping
2143 * on IO we've got bigger problems than wait queue collision.
2144 * Limit the size of the wait table to a reasonable size.
2146 size
= min(size
, 4096UL);
2148 return max(size
, 4UL);
2152 * A zone's size might be changed by hot-add, so it is not possible to determine
2153 * a suitable size for its wait_table. So we use the maximum size now.
2155 * The max wait table size = 4096 x sizeof(wait_queue_head_t). ie:
2157 * i386 (preemption config) : 4096 x 16 = 64Kbyte.
2158 * ia64, x86-64 (no preemption): 4096 x 20 = 80Kbyte.
2159 * ia64, x86-64 (preemption) : 4096 x 24 = 96Kbyte.
2161 * The maximum entries are prepared when a zone's memory is (512K + 256) pages
2162 * or more by the traditional way. (See above). It equals:
2164 * i386, x86-64, powerpc(4K page size) : = ( 2G + 1M)byte.
2165 * ia64(16K page size) : = ( 8G + 4M)byte.
2166 * powerpc (64K page size) : = (32G +16M)byte.
2168 static inline unsigned long wait_table_hash_nr_entries(unsigned long pages
)
2175 * This is an integer logarithm so that shifts can be used later
2176 * to extract the more random high bits from the multiplicative
2177 * hash function before the remainder is taken.
2179 static inline unsigned long wait_table_bits(unsigned long size
)
2184 #define LONG_ALIGN(x) (((x)+(sizeof(long))-1)&~((sizeof(long))-1))
2187 * Initially all pages are reserved - free ones are freed
2188 * up by free_all_bootmem() once the early boot process is
2189 * done. Non-atomic initialization, single-pass.
2191 void __meminit
memmap_init_zone(unsigned long size
, int nid
, unsigned long zone
,
2192 unsigned long start_pfn
, enum memmap_context context
)
2195 unsigned long end_pfn
= start_pfn
+ size
;
2198 for (pfn
= start_pfn
; pfn
< end_pfn
; pfn
++) {
2200 * There can be holes in boot-time mem_map[]s
2201 * handed to this function. They do not
2202 * exist on hotplugged memory.
2204 if (context
== MEMMAP_EARLY
) {
2205 if (!early_pfn_valid(pfn
))
2207 if (!early_pfn_in_nid(pfn
, nid
))
2210 page
= pfn_to_page(pfn
);
2211 set_page_links(page
, zone
, nid
, pfn
);
2212 init_page_count(page
);
2213 reset_page_mapcount(page
);
2214 SetPageReserved(page
);
2215 INIT_LIST_HEAD(&page
->lru
);
2216 #ifdef WANT_PAGE_VIRTUAL
2217 /* The shift won't overflow because ZONE_NORMAL is below 4G. */
2218 if (!is_highmem_idx(zone
))
2219 set_page_address(page
, __va(pfn
<< PAGE_SHIFT
));
2224 static void __meminit
zone_init_free_lists(struct pglist_data
*pgdat
,
2225 struct zone
*zone
, unsigned long size
)
2228 for (order
= 0; order
< MAX_ORDER
; order
++) {
2229 INIT_LIST_HEAD(&zone
->free_area
[order
].free_list
);
2230 zone
->free_area
[order
].nr_free
= 0;
2234 #ifndef __HAVE_ARCH_MEMMAP_INIT
2235 #define memmap_init(size, nid, zone, start_pfn) \
2236 memmap_init_zone((size), (nid), (zone), (start_pfn), MEMMAP_EARLY)
2239 static int __devinit
zone_batchsize(struct zone
*zone
)
2244 * The per-cpu-pages pools are set to around 1000th of the
2245 * size of the zone. But no more than 1/2 of a meg.
2247 * OK, so we don't know how big the cache is. So guess.
2249 batch
= zone
->present_pages
/ 1024;
2250 if (batch
* PAGE_SIZE
> 512 * 1024)
2251 batch
= (512 * 1024) / PAGE_SIZE
;
2252 batch
/= 4; /* We effectively *= 4 below */
2257 * Clamp the batch to a 2^n - 1 value. Having a power
2258 * of 2 value was found to be more likely to have
2259 * suboptimal cache aliasing properties in some cases.
2261 * For example if 2 tasks are alternately allocating
2262 * batches of pages, one task can end up with a lot
2263 * of pages of one half of the possible page colors
2264 * and the other with pages of the other colors.
2266 batch
= (1 << (fls(batch
+ batch
/2)-1)) - 1;
2271 inline void setup_pageset(struct per_cpu_pageset
*p
, unsigned long batch
)
2273 struct per_cpu_pages
*pcp
;
2275 memset(p
, 0, sizeof(*p
));
2277 pcp
= &p
->pcp
[0]; /* hot */
2279 pcp
->high
= 6 * batch
;
2280 pcp
->batch
= max(1UL, 1 * batch
);
2281 INIT_LIST_HEAD(&pcp
->list
);
2283 pcp
= &p
->pcp
[1]; /* cold*/
2285 pcp
->high
= 2 * batch
;
2286 pcp
->batch
= max(1UL, batch
/2);
2287 INIT_LIST_HEAD(&pcp
->list
);
2291 * setup_pagelist_highmark() sets the high water mark for hot per_cpu_pagelist
2292 * to the value high for the pageset p.
2295 static void setup_pagelist_highmark(struct per_cpu_pageset
*p
,
2298 struct per_cpu_pages
*pcp
;
2300 pcp
= &p
->pcp
[0]; /* hot list */
2302 pcp
->batch
= max(1UL, high
/4);
2303 if ((high
/4) > (PAGE_SHIFT
* 8))
2304 pcp
->batch
= PAGE_SHIFT
* 8;
2310 * Boot pageset table. One per cpu which is going to be used for all
2311 * zones and all nodes. The parameters will be set in such a way
2312 * that an item put on a list will immediately be handed over to
2313 * the buddy list. This is safe since pageset manipulation is done
2314 * with interrupts disabled.
2316 * Some NUMA counter updates may also be caught by the boot pagesets.
2318 * The boot_pagesets must be kept even after bootup is complete for
2319 * unused processors and/or zones. They do play a role for bootstrapping
2320 * hotplugged processors.
2322 * zoneinfo_show() and maybe other functions do
2323 * not check if the processor is online before following the pageset pointer.
2324 * Other parts of the kernel may not check if the zone is available.
2326 static struct per_cpu_pageset boot_pageset
[NR_CPUS
];
2329 * Dynamically allocate memory for the
2330 * per cpu pageset array in struct zone.
2332 static int __cpuinit
process_zones(int cpu
)
2334 struct zone
*zone
, *dzone
;
2336 for_each_zone(zone
) {
2338 if (!populated_zone(zone
))
2341 zone_pcp(zone
, cpu
) = kmalloc_node(sizeof(struct per_cpu_pageset
),
2342 GFP_KERNEL
, cpu_to_node(cpu
));
2343 if (!zone_pcp(zone
, cpu
))
2346 setup_pageset(zone_pcp(zone
, cpu
), zone_batchsize(zone
));
2348 if (percpu_pagelist_fraction
)
2349 setup_pagelist_highmark(zone_pcp(zone
, cpu
),
2350 (zone
->present_pages
/ percpu_pagelist_fraction
));
2355 for_each_zone(dzone
) {
2356 if (!populated_zone(dzone
))
2360 kfree(zone_pcp(dzone
, cpu
));
2361 zone_pcp(dzone
, cpu
) = NULL
;
2366 static inline void free_zone_pagesets(int cpu
)
2370 for_each_zone(zone
) {
2371 struct per_cpu_pageset
*pset
= zone_pcp(zone
, cpu
);
2373 /* Free per_cpu_pageset if it is slab allocated */
2374 if (pset
!= &boot_pageset
[cpu
])
2376 zone_pcp(zone
, cpu
) = NULL
;
2380 static int __cpuinit
pageset_cpuup_callback(struct notifier_block
*nfb
,
2381 unsigned long action
,
2384 int cpu
= (long)hcpu
;
2385 int ret
= NOTIFY_OK
;
2388 case CPU_UP_PREPARE
:
2389 case CPU_UP_PREPARE_FROZEN
:
2390 if (process_zones(cpu
))
2393 case CPU_UP_CANCELED
:
2394 case CPU_UP_CANCELED_FROZEN
:
2396 case CPU_DEAD_FROZEN
:
2397 free_zone_pagesets(cpu
);
2405 static struct notifier_block __cpuinitdata pageset_notifier
=
2406 { &pageset_cpuup_callback
, NULL
, 0 };
2408 void __init
setup_per_cpu_pageset(void)
2412 /* Initialize per_cpu_pageset for cpu 0.
2413 * A cpuup callback will do this for every cpu
2414 * as it comes online
2416 err
= process_zones(smp_processor_id());
2418 register_cpu_notifier(&pageset_notifier
);
2423 static noinline __init_refok
2424 int zone_wait_table_init(struct zone
*zone
, unsigned long zone_size_pages
)
2427 struct pglist_data
*pgdat
= zone
->zone_pgdat
;
2431 * The per-page waitqueue mechanism uses hashed waitqueues
2434 zone
->wait_table_hash_nr_entries
=
2435 wait_table_hash_nr_entries(zone_size_pages
);
2436 zone
->wait_table_bits
=
2437 wait_table_bits(zone
->wait_table_hash_nr_entries
);
2438 alloc_size
= zone
->wait_table_hash_nr_entries
2439 * sizeof(wait_queue_head_t
);
2441 if (system_state
== SYSTEM_BOOTING
) {
2442 zone
->wait_table
= (wait_queue_head_t
*)
2443 alloc_bootmem_node(pgdat
, alloc_size
);
2446 * This case means that a zone whose size was 0 gets new memory
2447 * via memory hot-add.
2448 * But it may be the case that a new node was hot-added. In
2449 * this case vmalloc() will not be able to use this new node's
2450 * memory - this wait_table must be initialized to use this new
2451 * node itself as well.
2452 * To use this new node's memory, further consideration will be
2455 zone
->wait_table
= vmalloc(alloc_size
);
2457 if (!zone
->wait_table
)
2460 for(i
= 0; i
< zone
->wait_table_hash_nr_entries
; ++i
)
2461 init_waitqueue_head(zone
->wait_table
+ i
);
2466 static __meminit
void zone_pcp_init(struct zone
*zone
)
2469 unsigned long batch
= zone_batchsize(zone
);
2471 for (cpu
= 0; cpu
< NR_CPUS
; cpu
++) {
2473 /* Early boot. Slab allocator not functional yet */
2474 zone_pcp(zone
, cpu
) = &boot_pageset
[cpu
];
2475 setup_pageset(&boot_pageset
[cpu
],0);
2477 setup_pageset(zone_pcp(zone
,cpu
), batch
);
2480 if (zone
->present_pages
)
2481 printk(KERN_DEBUG
" %s zone: %lu pages, LIFO batch:%lu\n",
2482 zone
->name
, zone
->present_pages
, batch
);
2485 __meminit
int init_currently_empty_zone(struct zone
*zone
,
2486 unsigned long zone_start_pfn
,
2488 enum memmap_context context
)
2490 struct pglist_data
*pgdat
= zone
->zone_pgdat
;
2492 ret
= zone_wait_table_init(zone
, size
);
2495 pgdat
->nr_zones
= zone_idx(zone
) + 1;
2497 zone
->zone_start_pfn
= zone_start_pfn
;
2499 memmap_init(size
, pgdat
->node_id
, zone_idx(zone
), zone_start_pfn
);
2501 zone_init_free_lists(pgdat
, zone
, zone
->spanned_pages
);
2506 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
2508 * Basic iterator support. Return the first range of PFNs for a node
2509 * Note: nid == MAX_NUMNODES returns first region regardless of node
2511 static int __meminit
first_active_region_index_in_nid(int nid
)
2515 for (i
= 0; i
< nr_nodemap_entries
; i
++)
2516 if (nid
== MAX_NUMNODES
|| early_node_map
[i
].nid
== nid
)
2523 * Basic iterator support. Return the next active range of PFNs for a node
2524 * Note: nid == MAX_NUMNODES returns next region regardles of node
2526 static int __meminit
next_active_region_index_in_nid(int index
, int nid
)
2528 for (index
= index
+ 1; index
< nr_nodemap_entries
; index
++)
2529 if (nid
== MAX_NUMNODES
|| early_node_map
[index
].nid
== nid
)
2535 #ifndef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
2537 * Required by SPARSEMEM. Given a PFN, return what node the PFN is on.
2538 * Architectures may implement their own version but if add_active_range()
2539 * was used and there are no special requirements, this is a convenient
2542 int __meminit
early_pfn_to_nid(unsigned long pfn
)
2546 for (i
= 0; i
< nr_nodemap_entries
; i
++) {
2547 unsigned long start_pfn
= early_node_map
[i
].start_pfn
;
2548 unsigned long end_pfn
= early_node_map
[i
].end_pfn
;
2550 if (start_pfn
<= pfn
&& pfn
< end_pfn
)
2551 return early_node_map
[i
].nid
;
2556 #endif /* CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID */
2558 /* Basic iterator support to walk early_node_map[] */
2559 #define for_each_active_range_index_in_nid(i, nid) \
2560 for (i = first_active_region_index_in_nid(nid); i != -1; \
2561 i = next_active_region_index_in_nid(i, nid))
2564 * free_bootmem_with_active_regions - Call free_bootmem_node for each active range
2565 * @nid: The node to free memory on. If MAX_NUMNODES, all nodes are freed.
2566 * @max_low_pfn: The highest PFN that will be passed to free_bootmem_node
2568 * If an architecture guarantees that all ranges registered with
2569 * add_active_ranges() contain no holes and may be freed, this
2570 * this function may be used instead of calling free_bootmem() manually.
2572 void __init
free_bootmem_with_active_regions(int nid
,
2573 unsigned long max_low_pfn
)
2577 for_each_active_range_index_in_nid(i
, nid
) {
2578 unsigned long size_pages
= 0;
2579 unsigned long end_pfn
= early_node_map
[i
].end_pfn
;
2581 if (early_node_map
[i
].start_pfn
>= max_low_pfn
)
2584 if (end_pfn
> max_low_pfn
)
2585 end_pfn
= max_low_pfn
;
2587 size_pages
= end_pfn
- early_node_map
[i
].start_pfn
;
2588 free_bootmem_node(NODE_DATA(early_node_map
[i
].nid
),
2589 PFN_PHYS(early_node_map
[i
].start_pfn
),
2590 size_pages
<< PAGE_SHIFT
);
2595 * sparse_memory_present_with_active_regions - Call memory_present for each active range
2596 * @nid: The node to call memory_present for. If MAX_NUMNODES, all nodes will be used.
2598 * If an architecture guarantees that all ranges registered with
2599 * add_active_ranges() contain no holes and may be freed, this
2600 * function may be used instead of calling memory_present() manually.
2602 void __init
sparse_memory_present_with_active_regions(int nid
)
2606 for_each_active_range_index_in_nid(i
, nid
)
2607 memory_present(early_node_map
[i
].nid
,
2608 early_node_map
[i
].start_pfn
,
2609 early_node_map
[i
].end_pfn
);
2613 * push_node_boundaries - Push node boundaries to at least the requested boundary
2614 * @nid: The nid of the node to push the boundary for
2615 * @start_pfn: The start pfn of the node
2616 * @end_pfn: The end pfn of the node
2618 * In reserve-based hot-add, mem_map is allocated that is unused until hotadd
2619 * time. Specifically, on x86_64, SRAT will report ranges that can potentially
2620 * be hotplugged even though no physical memory exists. This function allows
2621 * an arch to push out the node boundaries so mem_map is allocated that can
2624 #ifdef CONFIG_MEMORY_HOTPLUG_RESERVE
2625 void __init
push_node_boundaries(unsigned int nid
,
2626 unsigned long start_pfn
, unsigned long end_pfn
)
2628 printk(KERN_DEBUG
"Entering push_node_boundaries(%u, %lu, %lu)\n",
2629 nid
, start_pfn
, end_pfn
);
2631 /* Initialise the boundary for this node if necessary */
2632 if (node_boundary_end_pfn
[nid
] == 0)
2633 node_boundary_start_pfn
[nid
] = -1UL;
2635 /* Update the boundaries */
2636 if (node_boundary_start_pfn
[nid
] > start_pfn
)
2637 node_boundary_start_pfn
[nid
] = start_pfn
;
2638 if (node_boundary_end_pfn
[nid
] < end_pfn
)
2639 node_boundary_end_pfn
[nid
] = end_pfn
;
2642 /* If necessary, push the node boundary out for reserve hotadd */
2643 static void __meminit
account_node_boundary(unsigned int nid
,
2644 unsigned long *start_pfn
, unsigned long *end_pfn
)
2646 printk(KERN_DEBUG
"Entering account_node_boundary(%u, %lu, %lu)\n",
2647 nid
, *start_pfn
, *end_pfn
);
2649 /* Return if boundary information has not been provided */
2650 if (node_boundary_end_pfn
[nid
] == 0)
2653 /* Check the boundaries and update if necessary */
2654 if (node_boundary_start_pfn
[nid
] < *start_pfn
)
2655 *start_pfn
= node_boundary_start_pfn
[nid
];
2656 if (node_boundary_end_pfn
[nid
] > *end_pfn
)
2657 *end_pfn
= node_boundary_end_pfn
[nid
];
2660 void __init
push_node_boundaries(unsigned int nid
,
2661 unsigned long start_pfn
, unsigned long end_pfn
) {}
2663 static void __meminit
account_node_boundary(unsigned int nid
,
2664 unsigned long *start_pfn
, unsigned long *end_pfn
) {}
2669 * get_pfn_range_for_nid - Return the start and end page frames for a node
2670 * @nid: The nid to return the range for. If MAX_NUMNODES, the min and max PFN are returned.
2671 * @start_pfn: Passed by reference. On return, it will have the node start_pfn.
2672 * @end_pfn: Passed by reference. On return, it will have the node end_pfn.
2674 * It returns the start and end page frame of a node based on information
2675 * provided by an arch calling add_active_range(). If called for a node
2676 * with no available memory, a warning is printed and the start and end
2679 void __meminit
get_pfn_range_for_nid(unsigned int nid
,
2680 unsigned long *start_pfn
, unsigned long *end_pfn
)
2686 for_each_active_range_index_in_nid(i
, nid
) {
2687 *start_pfn
= min(*start_pfn
, early_node_map
[i
].start_pfn
);
2688 *end_pfn
= max(*end_pfn
, early_node_map
[i
].end_pfn
);
2691 if (*start_pfn
== -1UL) {
2692 printk(KERN_WARNING
"Node %u active with no memory\n", nid
);
2696 /* Push the node boundaries out if requested */
2697 account_node_boundary(nid
, start_pfn
, end_pfn
);
2701 * This finds a zone that can be used for ZONE_MOVABLE pages. The
2702 * assumption is made that zones within a node are ordered in monotonic
2703 * increasing memory addresses so that the "highest" populated zone is used
2705 void __init
find_usable_zone_for_movable(void)
2708 for (zone_index
= MAX_NR_ZONES
- 1; zone_index
>= 0; zone_index
--) {
2709 if (zone_index
== ZONE_MOVABLE
)
2712 if (arch_zone_highest_possible_pfn
[zone_index
] >
2713 arch_zone_lowest_possible_pfn
[zone_index
])
2717 VM_BUG_ON(zone_index
== -1);
2718 movable_zone
= zone_index
;
2722 * The zone ranges provided by the architecture do not include ZONE_MOVABLE
2723 * because it is sized independant of architecture. Unlike the other zones,
2724 * the starting point for ZONE_MOVABLE is not fixed. It may be different
2725 * in each node depending on the size of each node and how evenly kernelcore
2726 * is distributed. This helper function adjusts the zone ranges
2727 * provided by the architecture for a given node by using the end of the
2728 * highest usable zone for ZONE_MOVABLE. This preserves the assumption that
2729 * zones within a node are in order of monotonic increases memory addresses
2731 void __meminit
adjust_zone_range_for_zone_movable(int nid
,
2732 unsigned long zone_type
,
2733 unsigned long node_start_pfn
,
2734 unsigned long node_end_pfn
,
2735 unsigned long *zone_start_pfn
,
2736 unsigned long *zone_end_pfn
)
2738 /* Only adjust if ZONE_MOVABLE is on this node */
2739 if (zone_movable_pfn
[nid
]) {
2740 /* Size ZONE_MOVABLE */
2741 if (zone_type
== ZONE_MOVABLE
) {
2742 *zone_start_pfn
= zone_movable_pfn
[nid
];
2743 *zone_end_pfn
= min(node_end_pfn
,
2744 arch_zone_highest_possible_pfn
[movable_zone
]);
2746 /* Adjust for ZONE_MOVABLE starting within this range */
2747 } else if (*zone_start_pfn
< zone_movable_pfn
[nid
] &&
2748 *zone_end_pfn
> zone_movable_pfn
[nid
]) {
2749 *zone_end_pfn
= zone_movable_pfn
[nid
];
2751 /* Check if this whole range is within ZONE_MOVABLE */
2752 } else if (*zone_start_pfn
>= zone_movable_pfn
[nid
])
2753 *zone_start_pfn
= *zone_end_pfn
;
2758 * Return the number of pages a zone spans in a node, including holes
2759 * present_pages = zone_spanned_pages_in_node() - zone_absent_pages_in_node()
2761 static unsigned long __meminit
zone_spanned_pages_in_node(int nid
,
2762 unsigned long zone_type
,
2763 unsigned long *ignored
)
2765 unsigned long node_start_pfn
, node_end_pfn
;
2766 unsigned long zone_start_pfn
, zone_end_pfn
;
2768 /* Get the start and end of the node and zone */
2769 get_pfn_range_for_nid(nid
, &node_start_pfn
, &node_end_pfn
);
2770 zone_start_pfn
= arch_zone_lowest_possible_pfn
[zone_type
];
2771 zone_end_pfn
= arch_zone_highest_possible_pfn
[zone_type
];
2772 adjust_zone_range_for_zone_movable(nid
, zone_type
,
2773 node_start_pfn
, node_end_pfn
,
2774 &zone_start_pfn
, &zone_end_pfn
);
2776 /* Check that this node has pages within the zone's required range */
2777 if (zone_end_pfn
< node_start_pfn
|| zone_start_pfn
> node_end_pfn
)
2780 /* Move the zone boundaries inside the node if necessary */
2781 zone_end_pfn
= min(zone_end_pfn
, node_end_pfn
);
2782 zone_start_pfn
= max(zone_start_pfn
, node_start_pfn
);
2784 /* Return the spanned pages */
2785 return zone_end_pfn
- zone_start_pfn
;
2789 * Return the number of holes in a range on a node. If nid is MAX_NUMNODES,
2790 * then all holes in the requested range will be accounted for.
2792 unsigned long __meminit
__absent_pages_in_range(int nid
,
2793 unsigned long range_start_pfn
,
2794 unsigned long range_end_pfn
)
2797 unsigned long prev_end_pfn
= 0, hole_pages
= 0;
2798 unsigned long start_pfn
;
2800 /* Find the end_pfn of the first active range of pfns in the node */
2801 i
= first_active_region_index_in_nid(nid
);
2805 prev_end_pfn
= min(early_node_map
[i
].start_pfn
, range_end_pfn
);
2807 /* Account for ranges before physical memory on this node */
2808 if (early_node_map
[i
].start_pfn
> range_start_pfn
)
2809 hole_pages
= prev_end_pfn
- range_start_pfn
;
2811 /* Find all holes for the zone within the node */
2812 for (; i
!= -1; i
= next_active_region_index_in_nid(i
, nid
)) {
2814 /* No need to continue if prev_end_pfn is outside the zone */
2815 if (prev_end_pfn
>= range_end_pfn
)
2818 /* Make sure the end of the zone is not within the hole */
2819 start_pfn
= min(early_node_map
[i
].start_pfn
, range_end_pfn
);
2820 prev_end_pfn
= max(prev_end_pfn
, range_start_pfn
);
2822 /* Update the hole size cound and move on */
2823 if (start_pfn
> range_start_pfn
) {
2824 BUG_ON(prev_end_pfn
> start_pfn
);
2825 hole_pages
+= start_pfn
- prev_end_pfn
;
2827 prev_end_pfn
= early_node_map
[i
].end_pfn
;
2830 /* Account for ranges past physical memory on this node */
2831 if (range_end_pfn
> prev_end_pfn
)
2832 hole_pages
+= range_end_pfn
-
2833 max(range_start_pfn
, prev_end_pfn
);
2839 * absent_pages_in_range - Return number of page frames in holes within a range
2840 * @start_pfn: The start PFN to start searching for holes
2841 * @end_pfn: The end PFN to stop searching for holes
2843 * It returns the number of pages frames in memory holes within a range.
2845 unsigned long __init
absent_pages_in_range(unsigned long start_pfn
,
2846 unsigned long end_pfn
)
2848 return __absent_pages_in_range(MAX_NUMNODES
, start_pfn
, end_pfn
);
2851 /* Return the number of page frames in holes in a zone on a node */
2852 static unsigned long __meminit
zone_absent_pages_in_node(int nid
,
2853 unsigned long zone_type
,
2854 unsigned long *ignored
)
2856 unsigned long node_start_pfn
, node_end_pfn
;
2857 unsigned long zone_start_pfn
, zone_end_pfn
;
2859 get_pfn_range_for_nid(nid
, &node_start_pfn
, &node_end_pfn
);
2860 zone_start_pfn
= max(arch_zone_lowest_possible_pfn
[zone_type
],
2862 zone_end_pfn
= min(arch_zone_highest_possible_pfn
[zone_type
],
2865 adjust_zone_range_for_zone_movable(nid
, zone_type
,
2866 node_start_pfn
, node_end_pfn
,
2867 &zone_start_pfn
, &zone_end_pfn
);
2868 return __absent_pages_in_range(nid
, zone_start_pfn
, zone_end_pfn
);
2872 static inline unsigned long __meminit
zone_spanned_pages_in_node(int nid
,
2873 unsigned long zone_type
,
2874 unsigned long *zones_size
)
2876 return zones_size
[zone_type
];
2879 static inline unsigned long __meminit
zone_absent_pages_in_node(int nid
,
2880 unsigned long zone_type
,
2881 unsigned long *zholes_size
)
2886 return zholes_size
[zone_type
];
2891 static void __meminit
calculate_node_totalpages(struct pglist_data
*pgdat
,
2892 unsigned long *zones_size
, unsigned long *zholes_size
)
2894 unsigned long realtotalpages
, totalpages
= 0;
2897 for (i
= 0; i
< MAX_NR_ZONES
; i
++)
2898 totalpages
+= zone_spanned_pages_in_node(pgdat
->node_id
, i
,
2900 pgdat
->node_spanned_pages
= totalpages
;
2902 realtotalpages
= totalpages
;
2903 for (i
= 0; i
< MAX_NR_ZONES
; i
++)
2905 zone_absent_pages_in_node(pgdat
->node_id
, i
,
2907 pgdat
->node_present_pages
= realtotalpages
;
2908 printk(KERN_DEBUG
"On node %d totalpages: %lu\n", pgdat
->node_id
,
2913 * Set up the zone data structures:
2914 * - mark all pages reserved
2915 * - mark all memory queues empty
2916 * - clear the memory bitmaps
2918 static void __meminit
free_area_init_core(struct pglist_data
*pgdat
,
2919 unsigned long *zones_size
, unsigned long *zholes_size
)
2922 int nid
= pgdat
->node_id
;
2923 unsigned long zone_start_pfn
= pgdat
->node_start_pfn
;
2926 pgdat_resize_init(pgdat
);
2927 pgdat
->nr_zones
= 0;
2928 init_waitqueue_head(&pgdat
->kswapd_wait
);
2929 pgdat
->kswapd_max_order
= 0;
2931 for (j
= 0; j
< MAX_NR_ZONES
; j
++) {
2932 struct zone
*zone
= pgdat
->node_zones
+ j
;
2933 unsigned long size
, realsize
, memmap_pages
;
2935 size
= zone_spanned_pages_in_node(nid
, j
, zones_size
);
2936 realsize
= size
- zone_absent_pages_in_node(nid
, j
,
2940 * Adjust realsize so that it accounts for how much memory
2941 * is used by this zone for memmap. This affects the watermark
2942 * and per-cpu initialisations
2944 memmap_pages
= (size
* sizeof(struct page
)) >> PAGE_SHIFT
;
2945 if (realsize
>= memmap_pages
) {
2946 realsize
-= memmap_pages
;
2948 " %s zone: %lu pages used for memmap\n",
2949 zone_names
[j
], memmap_pages
);
2952 " %s zone: %lu pages exceeds realsize %lu\n",
2953 zone_names
[j
], memmap_pages
, realsize
);
2955 /* Account for reserved pages */
2956 if (j
== 0 && realsize
> dma_reserve
) {
2957 realsize
-= dma_reserve
;
2958 printk(KERN_DEBUG
" %s zone: %lu pages reserved\n",
2959 zone_names
[0], dma_reserve
);
2962 if (!is_highmem_idx(j
))
2963 nr_kernel_pages
+= realsize
;
2964 nr_all_pages
+= realsize
;
2966 zone
->spanned_pages
= size
;
2967 zone
->present_pages
= realsize
;
2970 zone
->min_unmapped_pages
= (realsize
*sysctl_min_unmapped_ratio
)
2972 zone
->min_slab_pages
= (realsize
* sysctl_min_slab_ratio
) / 100;
2974 zone
->name
= zone_names
[j
];
2975 spin_lock_init(&zone
->lock
);
2976 spin_lock_init(&zone
->lru_lock
);
2977 zone_seqlock_init(zone
);
2978 zone
->zone_pgdat
= pgdat
;
2980 zone
->prev_priority
= DEF_PRIORITY
;
2982 zone_pcp_init(zone
);
2983 INIT_LIST_HEAD(&zone
->active_list
);
2984 INIT_LIST_HEAD(&zone
->inactive_list
);
2985 zone
->nr_scan_active
= 0;
2986 zone
->nr_scan_inactive
= 0;
2987 zap_zone_vm_stats(zone
);
2988 atomic_set(&zone
->reclaim_in_progress
, 0);
2992 ret
= init_currently_empty_zone(zone
, zone_start_pfn
,
2993 size
, MEMMAP_EARLY
);
2995 zone_start_pfn
+= size
;
2999 static void __init_refok
alloc_node_mem_map(struct pglist_data
*pgdat
)
3001 /* Skip empty nodes */
3002 if (!pgdat
->node_spanned_pages
)
3005 #ifdef CONFIG_FLAT_NODE_MEM_MAP
3006 /* ia64 gets its own node_mem_map, before this, without bootmem */
3007 if (!pgdat
->node_mem_map
) {
3008 unsigned long size
, start
, end
;
3012 * The zone's endpoints aren't required to be MAX_ORDER
3013 * aligned but the node_mem_map endpoints must be in order
3014 * for the buddy allocator to function correctly.
3016 start
= pgdat
->node_start_pfn
& ~(MAX_ORDER_NR_PAGES
- 1);
3017 end
= pgdat
->node_start_pfn
+ pgdat
->node_spanned_pages
;
3018 end
= ALIGN(end
, MAX_ORDER_NR_PAGES
);
3019 size
= (end
- start
) * sizeof(struct page
);
3020 map
= alloc_remap(pgdat
->node_id
, size
);
3022 map
= alloc_bootmem_node(pgdat
, size
);
3023 pgdat
->node_mem_map
= map
+ (pgdat
->node_start_pfn
- start
);
3025 #ifndef CONFIG_NEED_MULTIPLE_NODES
3027 * With no DISCONTIG, the global mem_map is just set as node 0's
3029 if (pgdat
== NODE_DATA(0)) {
3030 mem_map
= NODE_DATA(0)->node_mem_map
;
3031 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
3032 if (page_to_pfn(mem_map
) != pgdat
->node_start_pfn
)
3033 mem_map
-= pgdat
->node_start_pfn
;
3034 #endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
3037 #endif /* CONFIG_FLAT_NODE_MEM_MAP */
3040 void __meminit
free_area_init_node(int nid
, struct pglist_data
*pgdat
,
3041 unsigned long *zones_size
, unsigned long node_start_pfn
,
3042 unsigned long *zholes_size
)
3044 pgdat
->node_id
= nid
;
3045 pgdat
->node_start_pfn
= node_start_pfn
;
3046 calculate_node_totalpages(pgdat
, zones_size
, zholes_size
);
3048 alloc_node_mem_map(pgdat
);
3050 free_area_init_core(pgdat
, zones_size
, zholes_size
);
3053 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
3055 #if MAX_NUMNODES > 1
3057 * Figure out the number of possible node ids.
3059 static void __init
setup_nr_node_ids(void)
3062 unsigned int highest
= 0;
3064 for_each_node_mask(node
, node_possible_map
)
3066 nr_node_ids
= highest
+ 1;
3069 static inline void setup_nr_node_ids(void)
3075 * add_active_range - Register a range of PFNs backed by physical memory
3076 * @nid: The node ID the range resides on
3077 * @start_pfn: The start PFN of the available physical memory
3078 * @end_pfn: The end PFN of the available physical memory
3080 * These ranges are stored in an early_node_map[] and later used by
3081 * free_area_init_nodes() to calculate zone sizes and holes. If the
3082 * range spans a memory hole, it is up to the architecture to ensure
3083 * the memory is not freed by the bootmem allocator. If possible
3084 * the range being registered will be merged with existing ranges.
3086 void __init
add_active_range(unsigned int nid
, unsigned long start_pfn
,
3087 unsigned long end_pfn
)
3091 printk(KERN_DEBUG
"Entering add_active_range(%d, %lu, %lu) "
3092 "%d entries of %d used\n",
3093 nid
, start_pfn
, end_pfn
,
3094 nr_nodemap_entries
, MAX_ACTIVE_REGIONS
);
3096 /* Merge with existing active regions if possible */
3097 for (i
= 0; i
< nr_nodemap_entries
; i
++) {
3098 if (early_node_map
[i
].nid
!= nid
)
3101 /* Skip if an existing region covers this new one */
3102 if (start_pfn
>= early_node_map
[i
].start_pfn
&&
3103 end_pfn
<= early_node_map
[i
].end_pfn
)
3106 /* Merge forward if suitable */
3107 if (start_pfn
<= early_node_map
[i
].end_pfn
&&
3108 end_pfn
> early_node_map
[i
].end_pfn
) {
3109 early_node_map
[i
].end_pfn
= end_pfn
;
3113 /* Merge backward if suitable */
3114 if (start_pfn
< early_node_map
[i
].end_pfn
&&
3115 end_pfn
>= early_node_map
[i
].start_pfn
) {
3116 early_node_map
[i
].start_pfn
= start_pfn
;
3121 /* Check that early_node_map is large enough */
3122 if (i
>= MAX_ACTIVE_REGIONS
) {
3123 printk(KERN_CRIT
"More than %d memory regions, truncating\n",
3124 MAX_ACTIVE_REGIONS
);
3128 early_node_map
[i
].nid
= nid
;
3129 early_node_map
[i
].start_pfn
= start_pfn
;
3130 early_node_map
[i
].end_pfn
= end_pfn
;
3131 nr_nodemap_entries
= i
+ 1;
3135 * shrink_active_range - Shrink an existing registered range of PFNs
3136 * @nid: The node id the range is on that should be shrunk
3137 * @old_end_pfn: The old end PFN of the range
3138 * @new_end_pfn: The new PFN of the range
3140 * i386 with NUMA use alloc_remap() to store a node_mem_map on a local node.
3141 * The map is kept at the end physical page range that has already been
3142 * registered with add_active_range(). This function allows an arch to shrink
3143 * an existing registered range.
3145 void __init
shrink_active_range(unsigned int nid
, unsigned long old_end_pfn
,
3146 unsigned long new_end_pfn
)
3150 /* Find the old active region end and shrink */
3151 for_each_active_range_index_in_nid(i
, nid
)
3152 if (early_node_map
[i
].end_pfn
== old_end_pfn
) {
3153 early_node_map
[i
].end_pfn
= new_end_pfn
;
3159 * remove_all_active_ranges - Remove all currently registered regions
3161 * During discovery, it may be found that a table like SRAT is invalid
3162 * and an alternative discovery method must be used. This function removes
3163 * all currently registered regions.
3165 void __init
remove_all_active_ranges(void)
3167 memset(early_node_map
, 0, sizeof(early_node_map
));
3168 nr_nodemap_entries
= 0;
3169 #ifdef CONFIG_MEMORY_HOTPLUG_RESERVE
3170 memset(node_boundary_start_pfn
, 0, sizeof(node_boundary_start_pfn
));
3171 memset(node_boundary_end_pfn
, 0, sizeof(node_boundary_end_pfn
));
3172 #endif /* CONFIG_MEMORY_HOTPLUG_RESERVE */
3175 /* Compare two active node_active_regions */
3176 static int __init
cmp_node_active_region(const void *a
, const void *b
)
3178 struct node_active_region
*arange
= (struct node_active_region
*)a
;
3179 struct node_active_region
*brange
= (struct node_active_region
*)b
;
3181 /* Done this way to avoid overflows */
3182 if (arange
->start_pfn
> brange
->start_pfn
)
3184 if (arange
->start_pfn
< brange
->start_pfn
)
3190 /* sort the node_map by start_pfn */
3191 static void __init
sort_node_map(void)
3193 sort(early_node_map
, (size_t)nr_nodemap_entries
,
3194 sizeof(struct node_active_region
),
3195 cmp_node_active_region
, NULL
);
3198 /* Find the lowest pfn for a node */
3199 unsigned long __init
find_min_pfn_for_node(unsigned long nid
)
3202 unsigned long min_pfn
= ULONG_MAX
;
3204 /* Assuming a sorted map, the first range found has the starting pfn */
3205 for_each_active_range_index_in_nid(i
, nid
)
3206 min_pfn
= min(min_pfn
, early_node_map
[i
].start_pfn
);
3208 if (min_pfn
== ULONG_MAX
) {
3210 "Could not find start_pfn for node %lu\n", nid
);
3218 * find_min_pfn_with_active_regions - Find the minimum PFN registered
3220 * It returns the minimum PFN based on information provided via
3221 * add_active_range().
3223 unsigned long __init
find_min_pfn_with_active_regions(void)
3225 return find_min_pfn_for_node(MAX_NUMNODES
);
3229 * find_max_pfn_with_active_regions - Find the maximum PFN registered
3231 * It returns the maximum PFN based on information provided via
3232 * add_active_range().
3234 unsigned long __init
find_max_pfn_with_active_regions(void)
3237 unsigned long max_pfn
= 0;
3239 for (i
= 0; i
< nr_nodemap_entries
; i
++)
3240 max_pfn
= max(max_pfn
, early_node_map
[i
].end_pfn
);
3245 unsigned long __init
early_calculate_totalpages(void)
3248 unsigned long totalpages
= 0;
3250 for (i
= 0; i
< nr_nodemap_entries
; i
++)
3251 totalpages
+= early_node_map
[i
].end_pfn
-
3252 early_node_map
[i
].start_pfn
;
3258 * Find the PFN the Movable zone begins in each node. Kernel memory
3259 * is spread evenly between nodes as long as the nodes have enough
3260 * memory. When they don't, some nodes will have more kernelcore than
3263 void __init
find_zone_movable_pfns_for_nodes(unsigned long *movable_pfn
)
3266 unsigned long usable_startpfn
;
3267 unsigned long kernelcore_node
, kernelcore_remaining
;
3268 int usable_nodes
= num_online_nodes();
3271 * If movablecore was specified, calculate what size of
3272 * kernelcore that corresponds so that memory usable for
3273 * any allocation type is evenly spread. If both kernelcore
3274 * and movablecore are specified, then the value of kernelcore
3275 * will be used for required_kernelcore if it's greater than
3276 * what movablecore would have allowed.
3278 if (required_movablecore
) {
3279 unsigned long totalpages
= early_calculate_totalpages();
3280 unsigned long corepages
;
3283 * Round-up so that ZONE_MOVABLE is at least as large as what
3284 * was requested by the user
3286 required_movablecore
=
3287 roundup(required_movablecore
, MAX_ORDER_NR_PAGES
);
3288 corepages
= totalpages
- required_movablecore
;
3290 required_kernelcore
= max(required_kernelcore
, corepages
);
3293 /* If kernelcore was not specified, there is no ZONE_MOVABLE */
3294 if (!required_kernelcore
)
3297 /* usable_startpfn is the lowest possible pfn ZONE_MOVABLE can be at */
3298 find_usable_zone_for_movable();
3299 usable_startpfn
= arch_zone_lowest_possible_pfn
[movable_zone
];
3302 /* Spread kernelcore memory as evenly as possible throughout nodes */
3303 kernelcore_node
= required_kernelcore
/ usable_nodes
;
3304 for_each_online_node(nid
) {
3306 * Recalculate kernelcore_node if the division per node
3307 * now exceeds what is necessary to satisfy the requested
3308 * amount of memory for the kernel
3310 if (required_kernelcore
< kernelcore_node
)
3311 kernelcore_node
= required_kernelcore
/ usable_nodes
;
3314 * As the map is walked, we track how much memory is usable
3315 * by the kernel using kernelcore_remaining. When it is
3316 * 0, the rest of the node is usable by ZONE_MOVABLE
3318 kernelcore_remaining
= kernelcore_node
;
3320 /* Go through each range of PFNs within this node */
3321 for_each_active_range_index_in_nid(i
, nid
) {
3322 unsigned long start_pfn
, end_pfn
;
3323 unsigned long size_pages
;
3325 start_pfn
= max(early_node_map
[i
].start_pfn
,
3326 zone_movable_pfn
[nid
]);
3327 end_pfn
= early_node_map
[i
].end_pfn
;
3328 if (start_pfn
>= end_pfn
)
3331 /* Account for what is only usable for kernelcore */
3332 if (start_pfn
< usable_startpfn
) {
3333 unsigned long kernel_pages
;
3334 kernel_pages
= min(end_pfn
, usable_startpfn
)
3337 kernelcore_remaining
-= min(kernel_pages
,
3338 kernelcore_remaining
);
3339 required_kernelcore
-= min(kernel_pages
,
3340 required_kernelcore
);
3342 /* Continue if range is now fully accounted */
3343 if (end_pfn
<= usable_startpfn
) {
3346 * Push zone_movable_pfn to the end so
3347 * that if we have to rebalance
3348 * kernelcore across nodes, we will
3349 * not double account here
3351 zone_movable_pfn
[nid
] = end_pfn
;
3354 start_pfn
= usable_startpfn
;
3358 * The usable PFN range for ZONE_MOVABLE is from
3359 * start_pfn->end_pfn. Calculate size_pages as the
3360 * number of pages used as kernelcore
3362 size_pages
= end_pfn
- start_pfn
;
3363 if (size_pages
> kernelcore_remaining
)
3364 size_pages
= kernelcore_remaining
;
3365 zone_movable_pfn
[nid
] = start_pfn
+ size_pages
;
3368 * Some kernelcore has been met, update counts and
3369 * break if the kernelcore for this node has been
3372 required_kernelcore
-= min(required_kernelcore
,
3374 kernelcore_remaining
-= size_pages
;
3375 if (!kernelcore_remaining
)
3381 * If there is still required_kernelcore, we do another pass with one
3382 * less node in the count. This will push zone_movable_pfn[nid] further
3383 * along on the nodes that still have memory until kernelcore is
3387 if (usable_nodes
&& required_kernelcore
> usable_nodes
)
3390 /* Align start of ZONE_MOVABLE on all nids to MAX_ORDER_NR_PAGES */
3391 for (nid
= 0; nid
< MAX_NUMNODES
; nid
++)
3392 zone_movable_pfn
[nid
] =
3393 roundup(zone_movable_pfn
[nid
], MAX_ORDER_NR_PAGES
);
3397 * free_area_init_nodes - Initialise all pg_data_t and zone data
3398 * @max_zone_pfn: an array of max PFNs for each zone
3400 * This will call free_area_init_node() for each active node in the system.
3401 * Using the page ranges provided by add_active_range(), the size of each
3402 * zone in each node and their holes is calculated. If the maximum PFN
3403 * between two adjacent zones match, it is assumed that the zone is empty.
3404 * For example, if arch_max_dma_pfn == arch_max_dma32_pfn, it is assumed
3405 * that arch_max_dma32_pfn has no pages. It is also assumed that a zone
3406 * starts where the previous one ended. For example, ZONE_DMA32 starts
3407 * at arch_max_dma_pfn.
3409 void __init
free_area_init_nodes(unsigned long *max_zone_pfn
)
3414 /* Sort early_node_map as initialisation assumes it is sorted */
3417 /* Record where the zone boundaries are */
3418 memset(arch_zone_lowest_possible_pfn
, 0,
3419 sizeof(arch_zone_lowest_possible_pfn
));
3420 memset(arch_zone_highest_possible_pfn
, 0,
3421 sizeof(arch_zone_highest_possible_pfn
));
3422 arch_zone_lowest_possible_pfn
[0] = find_min_pfn_with_active_regions();
3423 arch_zone_highest_possible_pfn
[0] = max_zone_pfn
[0];
3424 for (i
= 1; i
< MAX_NR_ZONES
; i
++) {
3425 if (i
== ZONE_MOVABLE
)
3427 arch_zone_lowest_possible_pfn
[i
] =
3428 arch_zone_highest_possible_pfn
[i
-1];
3429 arch_zone_highest_possible_pfn
[i
] =
3430 max(max_zone_pfn
[i
], arch_zone_lowest_possible_pfn
[i
]);
3432 arch_zone_lowest_possible_pfn
[ZONE_MOVABLE
] = 0;
3433 arch_zone_highest_possible_pfn
[ZONE_MOVABLE
] = 0;
3435 /* Find the PFNs that ZONE_MOVABLE begins at in each node */
3436 memset(zone_movable_pfn
, 0, sizeof(zone_movable_pfn
));
3437 find_zone_movable_pfns_for_nodes(zone_movable_pfn
);
3439 /* Print out the zone ranges */
3440 printk("Zone PFN ranges:\n");
3441 for (i
= 0; i
< MAX_NR_ZONES
; i
++) {
3442 if (i
== ZONE_MOVABLE
)
3444 printk(" %-8s %8lu -> %8lu\n",
3446 arch_zone_lowest_possible_pfn
[i
],
3447 arch_zone_highest_possible_pfn
[i
]);
3450 /* Print out the PFNs ZONE_MOVABLE begins at in each node */
3451 printk("Movable zone start PFN for each node\n");
3452 for (i
= 0; i
< MAX_NUMNODES
; i
++) {
3453 if (zone_movable_pfn
[i
])
3454 printk(" Node %d: %lu\n", i
, zone_movable_pfn
[i
]);
3457 /* Print out the early_node_map[] */
3458 printk("early_node_map[%d] active PFN ranges\n", nr_nodemap_entries
);
3459 for (i
= 0; i
< nr_nodemap_entries
; i
++)
3460 printk(" %3d: %8lu -> %8lu\n", early_node_map
[i
].nid
,
3461 early_node_map
[i
].start_pfn
,
3462 early_node_map
[i
].end_pfn
);
3464 /* Initialise every node */
3465 setup_nr_node_ids();
3466 for_each_online_node(nid
) {
3467 pg_data_t
*pgdat
= NODE_DATA(nid
);
3468 free_area_init_node(nid
, pgdat
, NULL
,
3469 find_min_pfn_for_node(nid
), NULL
);
3473 static int __init
cmdline_parse_core(char *p
, unsigned long *core
)
3475 unsigned long long coremem
;
3479 coremem
= memparse(p
, &p
);
3480 *core
= coremem
>> PAGE_SHIFT
;
3482 /* Paranoid check that UL is enough for the coremem value */
3483 WARN_ON((coremem
>> PAGE_SHIFT
) > ULONG_MAX
);
3489 * kernelcore=size sets the amount of memory for use for allocations that
3490 * cannot be reclaimed or migrated.
3492 static int __init
cmdline_parse_kernelcore(char *p
)
3494 return cmdline_parse_core(p
, &required_kernelcore
);
3498 * movablecore=size sets the amount of memory for use for allocations that
3499 * can be reclaimed or migrated.
3501 static int __init
cmdline_parse_movablecore(char *p
)
3503 return cmdline_parse_core(p
, &required_movablecore
);
3506 early_param("kernelcore", cmdline_parse_kernelcore
);
3507 early_param("movablecore", cmdline_parse_movablecore
);
3509 #endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
3512 * set_dma_reserve - set the specified number of pages reserved in the first zone
3513 * @new_dma_reserve: The number of pages to mark reserved
3515 * The per-cpu batchsize and zone watermarks are determined by present_pages.
3516 * In the DMA zone, a significant percentage may be consumed by kernel image
3517 * and other unfreeable allocations which can skew the watermarks badly. This
3518 * function may optionally be used to account for unfreeable pages in the
3519 * first zone (e.g., ZONE_DMA). The effect will be lower watermarks and
3520 * smaller per-cpu batchsize.
3522 void __init
set_dma_reserve(unsigned long new_dma_reserve
)
3524 dma_reserve
= new_dma_reserve
;
3527 #ifndef CONFIG_NEED_MULTIPLE_NODES
3528 static bootmem_data_t contig_bootmem_data
;
3529 struct pglist_data contig_page_data
= { .bdata
= &contig_bootmem_data
};
3531 EXPORT_SYMBOL(contig_page_data
);
3534 void __init
free_area_init(unsigned long *zones_size
)
3536 free_area_init_node(0, NODE_DATA(0), zones_size
,
3537 __pa(PAGE_OFFSET
) >> PAGE_SHIFT
, NULL
);
3540 static int page_alloc_cpu_notify(struct notifier_block
*self
,
3541 unsigned long action
, void *hcpu
)
3543 int cpu
= (unsigned long)hcpu
;
3545 if (action
== CPU_DEAD
|| action
== CPU_DEAD_FROZEN
) {
3546 local_irq_disable();
3548 vm_events_fold_cpu(cpu
);
3550 refresh_cpu_vm_stats(cpu
);
3555 void __init
page_alloc_init(void)
3557 hotcpu_notifier(page_alloc_cpu_notify
, 0);
3561 * calculate_totalreserve_pages - called when sysctl_lower_zone_reserve_ratio
3562 * or min_free_kbytes changes.
3564 static void calculate_totalreserve_pages(void)
3566 struct pglist_data
*pgdat
;
3567 unsigned long reserve_pages
= 0;
3568 enum zone_type i
, j
;
3570 for_each_online_pgdat(pgdat
) {
3571 for (i
= 0; i
< MAX_NR_ZONES
; i
++) {
3572 struct zone
*zone
= pgdat
->node_zones
+ i
;
3573 unsigned long max
= 0;
3575 /* Find valid and maximum lowmem_reserve in the zone */
3576 for (j
= i
; j
< MAX_NR_ZONES
; j
++) {
3577 if (zone
->lowmem_reserve
[j
] > max
)
3578 max
= zone
->lowmem_reserve
[j
];
3581 /* we treat pages_high as reserved pages. */
3582 max
+= zone
->pages_high
;
3584 if (max
> zone
->present_pages
)
3585 max
= zone
->present_pages
;
3586 reserve_pages
+= max
;
3589 totalreserve_pages
= reserve_pages
;
3593 * setup_per_zone_lowmem_reserve - called whenever
3594 * sysctl_lower_zone_reserve_ratio changes. Ensures that each zone
3595 * has a correct pages reserved value, so an adequate number of
3596 * pages are left in the zone after a successful __alloc_pages().
3598 static void setup_per_zone_lowmem_reserve(void)
3600 struct pglist_data
*pgdat
;
3601 enum zone_type j
, idx
;
3603 for_each_online_pgdat(pgdat
) {
3604 for (j
= 0; j
< MAX_NR_ZONES
; j
++) {
3605 struct zone
*zone
= pgdat
->node_zones
+ j
;
3606 unsigned long present_pages
= zone
->present_pages
;
3608 zone
->lowmem_reserve
[j
] = 0;
3612 struct zone
*lower_zone
;
3616 if (sysctl_lowmem_reserve_ratio
[idx
] < 1)
3617 sysctl_lowmem_reserve_ratio
[idx
] = 1;
3619 lower_zone
= pgdat
->node_zones
+ idx
;
3620 lower_zone
->lowmem_reserve
[j
] = present_pages
/
3621 sysctl_lowmem_reserve_ratio
[idx
];
3622 present_pages
+= lower_zone
->present_pages
;
3627 /* update totalreserve_pages */
3628 calculate_totalreserve_pages();
3632 * setup_per_zone_pages_min - called when min_free_kbytes changes.
3634 * Ensures that the pages_{min,low,high} values for each zone are set correctly
3635 * with respect to min_free_kbytes.
3637 void setup_per_zone_pages_min(void)
3639 unsigned long pages_min
= min_free_kbytes
>> (PAGE_SHIFT
- 10);
3640 unsigned long lowmem_pages
= 0;
3642 unsigned long flags
;
3644 /* Calculate total number of !ZONE_HIGHMEM pages */
3645 for_each_zone(zone
) {
3646 if (!is_highmem(zone
))
3647 lowmem_pages
+= zone
->present_pages
;
3650 for_each_zone(zone
) {
3653 spin_lock_irqsave(&zone
->lru_lock
, flags
);
3654 tmp
= (u64
)pages_min
* zone
->present_pages
;
3655 do_div(tmp
, lowmem_pages
);
3656 if (is_highmem(zone
)) {
3658 * __GFP_HIGH and PF_MEMALLOC allocations usually don't
3659 * need highmem pages, so cap pages_min to a small
3662 * The (pages_high-pages_low) and (pages_low-pages_min)
3663 * deltas controls asynch page reclaim, and so should
3664 * not be capped for highmem.
3668 min_pages
= zone
->present_pages
/ 1024;
3669 if (min_pages
< SWAP_CLUSTER_MAX
)
3670 min_pages
= SWAP_CLUSTER_MAX
;
3671 if (min_pages
> 128)
3673 zone
->pages_min
= min_pages
;
3676 * If it's a lowmem zone, reserve a number of pages
3677 * proportionate to the zone's size.
3679 zone
->pages_min
= tmp
;
3682 zone
->pages_low
= zone
->pages_min
+ (tmp
>> 2);
3683 zone
->pages_high
= zone
->pages_min
+ (tmp
>> 1);
3684 spin_unlock_irqrestore(&zone
->lru_lock
, flags
);
3687 /* update totalreserve_pages */
3688 calculate_totalreserve_pages();
3692 * Initialise min_free_kbytes.
3694 * For small machines we want it small (128k min). For large machines
3695 * we want it large (64MB max). But it is not linear, because network
3696 * bandwidth does not increase linearly with machine size. We use
3698 * min_free_kbytes = 4 * sqrt(lowmem_kbytes), for better accuracy:
3699 * min_free_kbytes = sqrt(lowmem_kbytes * 16)
3715 static int __init
init_per_zone_pages_min(void)
3717 unsigned long lowmem_kbytes
;
3719 lowmem_kbytes
= nr_free_buffer_pages() * (PAGE_SIZE
>> 10);
3721 min_free_kbytes
= int_sqrt(lowmem_kbytes
* 16);
3722 if (min_free_kbytes
< 128)
3723 min_free_kbytes
= 128;
3724 if (min_free_kbytes
> 65536)
3725 min_free_kbytes
= 65536;
3726 setup_per_zone_pages_min();
3727 setup_per_zone_lowmem_reserve();
3730 module_init(init_per_zone_pages_min
)
3733 * min_free_kbytes_sysctl_handler - just a wrapper around proc_dointvec() so
3734 * that we can call two helper functions whenever min_free_kbytes
3737 int min_free_kbytes_sysctl_handler(ctl_table
*table
, int write
,
3738 struct file
*file
, void __user
*buffer
, size_t *length
, loff_t
*ppos
)
3740 proc_dointvec(table
, write
, file
, buffer
, length
, ppos
);
3742 setup_per_zone_pages_min();
3747 int sysctl_min_unmapped_ratio_sysctl_handler(ctl_table
*table
, int write
,
3748 struct file
*file
, void __user
*buffer
, size_t *length
, loff_t
*ppos
)
3753 rc
= proc_dointvec_minmax(table
, write
, file
, buffer
, length
, ppos
);
3758 zone
->min_unmapped_pages
= (zone
->present_pages
*
3759 sysctl_min_unmapped_ratio
) / 100;
3763 int sysctl_min_slab_ratio_sysctl_handler(ctl_table
*table
, int write
,
3764 struct file
*file
, void __user
*buffer
, size_t *length
, loff_t
*ppos
)
3769 rc
= proc_dointvec_minmax(table
, write
, file
, buffer
, length
, ppos
);
3774 zone
->min_slab_pages
= (zone
->present_pages
*
3775 sysctl_min_slab_ratio
) / 100;
3781 * lowmem_reserve_ratio_sysctl_handler - just a wrapper around
3782 * proc_dointvec() so that we can call setup_per_zone_lowmem_reserve()
3783 * whenever sysctl_lowmem_reserve_ratio changes.
3785 * The reserve ratio obviously has absolutely no relation with the
3786 * pages_min watermarks. The lowmem reserve ratio can only make sense
3787 * if in function of the boot time zone sizes.
3789 int lowmem_reserve_ratio_sysctl_handler(ctl_table
*table
, int write
,
3790 struct file
*file
, void __user
*buffer
, size_t *length
, loff_t
*ppos
)
3792 proc_dointvec_minmax(table
, write
, file
, buffer
, length
, ppos
);
3793 setup_per_zone_lowmem_reserve();
3798 * percpu_pagelist_fraction - changes the pcp->high for each zone on each
3799 * cpu. It is the fraction of total pages in each zone that a hot per cpu pagelist
3800 * can have before it gets flushed back to buddy allocator.
3803 int percpu_pagelist_fraction_sysctl_handler(ctl_table
*table
, int write
,
3804 struct file
*file
, void __user
*buffer
, size_t *length
, loff_t
*ppos
)
3810 ret
= proc_dointvec_minmax(table
, write
, file
, buffer
, length
, ppos
);
3811 if (!write
|| (ret
== -EINVAL
))
3813 for_each_zone(zone
) {
3814 for_each_online_cpu(cpu
) {
3816 high
= zone
->present_pages
/ percpu_pagelist_fraction
;
3817 setup_pagelist_highmark(zone_pcp(zone
, cpu
), high
);
3823 int hashdist
= HASHDIST_DEFAULT
;
3826 static int __init
set_hashdist(char *str
)
3830 hashdist
= simple_strtoul(str
, &str
, 0);
3833 __setup("hashdist=", set_hashdist
);
3837 * allocate a large system hash table from bootmem
3838 * - it is assumed that the hash table must contain an exact power-of-2
3839 * quantity of entries
3840 * - limit is the number of hash buckets, not the total allocation size
3842 void *__init
alloc_large_system_hash(const char *tablename
,
3843 unsigned long bucketsize
,
3844 unsigned long numentries
,
3847 unsigned int *_hash_shift
,
3848 unsigned int *_hash_mask
,
3849 unsigned long limit
)
3851 unsigned long long max
= limit
;
3852 unsigned long log2qty
, size
;
3855 /* allow the kernel cmdline to have a say */
3857 /* round applicable memory size up to nearest megabyte */
3858 numentries
= nr_kernel_pages
;
3859 numentries
+= (1UL << (20 - PAGE_SHIFT
)) - 1;
3860 numentries
>>= 20 - PAGE_SHIFT
;
3861 numentries
<<= 20 - PAGE_SHIFT
;
3863 /* limit to 1 bucket per 2^scale bytes of low memory */
3864 if (scale
> PAGE_SHIFT
)
3865 numentries
>>= (scale
- PAGE_SHIFT
);
3867 numentries
<<= (PAGE_SHIFT
- scale
);
3869 /* Make sure we've got at least a 0-order allocation.. */
3870 if (unlikely((numentries
* bucketsize
) < PAGE_SIZE
))
3871 numentries
= PAGE_SIZE
/ bucketsize
;
3873 numentries
= roundup_pow_of_two(numentries
);
3875 /* limit allocation size to 1/16 total memory by default */
3877 max
= ((unsigned long long)nr_all_pages
<< PAGE_SHIFT
) >> 4;
3878 do_div(max
, bucketsize
);
3881 if (numentries
> max
)
3884 log2qty
= ilog2(numentries
);
3887 size
= bucketsize
<< log2qty
;
3888 if (flags
& HASH_EARLY
)
3889 table
= alloc_bootmem(size
);
3891 table
= __vmalloc(size
, GFP_ATOMIC
, PAGE_KERNEL
);
3893 unsigned long order
;
3894 for (order
= 0; ((1UL << order
) << PAGE_SHIFT
) < size
; order
++)
3896 table
= (void*) __get_free_pages(GFP_ATOMIC
, order
);
3898 * If bucketsize is not a power-of-two, we may free
3899 * some pages at the end of hash table.
3902 unsigned long alloc_end
= (unsigned long)table
+
3903 (PAGE_SIZE
<< order
);
3904 unsigned long used
= (unsigned long)table
+
3906 split_page(virt_to_page(table
), order
);
3907 while (used
< alloc_end
) {
3913 } while (!table
&& size
> PAGE_SIZE
&& --log2qty
);
3916 panic("Failed to allocate %s hash table\n", tablename
);
3918 printk(KERN_INFO
"%s hash table entries: %d (order: %d, %lu bytes)\n",
3921 ilog2(size
) - PAGE_SHIFT
,
3925 *_hash_shift
= log2qty
;
3927 *_hash_mask
= (1 << log2qty
) - 1;
3932 #ifdef CONFIG_OUT_OF_LINE_PFN_TO_PAGE
3933 struct page
*pfn_to_page(unsigned long pfn
)
3935 return __pfn_to_page(pfn
);
3937 unsigned long page_to_pfn(struct page
*page
)
3939 return __page_to_pfn(page
);
3941 EXPORT_SYMBOL(pfn_to_page
);
3942 EXPORT_SYMBOL(page_to_pfn
);
3943 #endif /* CONFIG_OUT_OF_LINE_PFN_TO_PAGE */