2 * linux/mm/page_alloc.c
4 * Manages the free list, the system allocates free pages here.
5 * Note that kmalloc() lives in slab.c
7 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
8 * Swap reorganised 29.12.95, Stephen Tweedie
9 * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999
10 * Reshaped it to be a zoned allocator, Ingo Molnar, Red Hat, 1999
11 * Discontiguous memory support, Kanoj Sarcar, SGI, Nov 1999
12 * Zone balancing, Kanoj Sarcar, SGI, Jan 2000
13 * Per cpu hot/cold page lists, bulk allocation, Martin J. Bligh, Sept 2002
14 * (lots of bits borrowed from Ingo Molnar & Andrew Morton)
17 #include <linux/stddef.h>
19 #include <linux/swap.h>
20 #include <linux/interrupt.h>
21 #include <linux/pagemap.h>
22 #include <linux/jiffies.h>
23 #include <linux/bootmem.h>
24 #include <linux/compiler.h>
25 #include <linux/kernel.h>
26 #include <linux/kmemcheck.h>
27 #include <linux/module.h>
28 #include <linux/suspend.h>
29 #include <linux/pagevec.h>
30 #include <linux/blkdev.h>
31 #include <linux/slab.h>
32 #include <linux/oom.h>
33 #include <linux/notifier.h>
34 #include <linux/topology.h>
35 #include <linux/sysctl.h>
36 #include <linux/cpu.h>
37 #include <linux/cpuset.h>
38 #include <linux/memory_hotplug.h>
39 #include <linux/nodemask.h>
40 #include <linux/vmalloc.h>
41 #include <linux/mempolicy.h>
42 #include <linux/stop_machine.h>
43 #include <linux/sort.h>
44 #include <linux/pfn.h>
45 #include <linux/backing-dev.h>
46 #include <linux/fault-inject.h>
47 #include <linux/page-isolation.h>
48 #include <linux/page_cgroup.h>
49 #include <linux/debugobjects.h>
50 #include <linux/kmemleak.h>
51 #include <linux/memory.h>
52 #include <linux/compaction.h>
53 #include <trace/events/kmem.h>
54 #include <linux/ftrace_event.h>
56 #include <asm/tlbflush.h>
57 #include <asm/div64.h>
61 * Array of node states.
63 nodemask_t node_states
[NR_NODE_STATES
] __read_mostly
= {
64 [N_POSSIBLE
] = NODE_MASK_ALL
,
65 [N_ONLINE
] = { { [0] = 1UL } },
67 [N_NORMAL_MEMORY
] = { { [0] = 1UL } },
69 [N_HIGH_MEMORY
] = { { [0] = 1UL } },
71 [N_CPU
] = { { [0] = 1UL } },
74 EXPORT_SYMBOL(node_states
);
76 unsigned long totalram_pages __read_mostly
;
77 unsigned long totalreserve_pages __read_mostly
;
78 int percpu_pagelist_fraction
;
79 gfp_t gfp_allowed_mask __read_mostly
= GFP_BOOT_MASK
;
81 #ifdef CONFIG_PM_SLEEP
83 * The following functions are used by the suspend/hibernate code to temporarily
84 * change gfp_allowed_mask in order to avoid using I/O during memory allocations
85 * while devices are suspended. To avoid races with the suspend/hibernate code,
86 * they should always be called with pm_mutex held (gfp_allowed_mask also should
87 * only be modified with pm_mutex held, unless the suspend/hibernate code is
88 * guaranteed not to run in parallel with that modification).
90 void set_gfp_allowed_mask(gfp_t mask
)
92 WARN_ON(!mutex_is_locked(&pm_mutex
));
93 gfp_allowed_mask
= mask
;
96 gfp_t
clear_gfp_allowed_mask(gfp_t mask
)
98 gfp_t ret
= gfp_allowed_mask
;
100 WARN_ON(!mutex_is_locked(&pm_mutex
));
101 gfp_allowed_mask
&= ~mask
;
104 #endif /* CONFIG_PM_SLEEP */
106 #ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
107 int pageblock_order __read_mostly
;
110 static void __free_pages_ok(struct page
*page
, unsigned int order
);
113 * results with 256, 32 in the lowmem_reserve sysctl:
114 * 1G machine -> (16M dma, 800M-16M normal, 1G-800M high)
115 * 1G machine -> (16M dma, 784M normal, 224M high)
116 * NORMAL allocation will leave 784M/256 of ram reserved in the ZONE_DMA
117 * HIGHMEM allocation will leave 224M/32 of ram reserved in ZONE_NORMAL
118 * HIGHMEM allocation will (224M+784M)/256 of ram reserved in ZONE_DMA
120 * TBD: should special case ZONE_DMA32 machines here - in those we normally
121 * don't need any ZONE_NORMAL reservation
123 int sysctl_lowmem_reserve_ratio
[MAX_NR_ZONES
-1] = {
124 #ifdef CONFIG_ZONE_DMA
127 #ifdef CONFIG_ZONE_DMA32
130 #ifdef CONFIG_HIGHMEM
136 EXPORT_SYMBOL(totalram_pages
);
138 static char * const zone_names
[MAX_NR_ZONES
] = {
139 #ifdef CONFIG_ZONE_DMA
142 #ifdef CONFIG_ZONE_DMA32
146 #ifdef CONFIG_HIGHMEM
152 int min_free_kbytes
= 1024;
154 static unsigned long __meminitdata nr_kernel_pages
;
155 static unsigned long __meminitdata nr_all_pages
;
156 static unsigned long __meminitdata dma_reserve
;
158 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
160 * MAX_ACTIVE_REGIONS determines the maximum number of distinct
161 * ranges of memory (RAM) that may be registered with add_active_range().
162 * Ranges passed to add_active_range() will be merged if possible
163 * so the number of times add_active_range() can be called is
164 * related to the number of nodes and the number of holes
166 #ifdef CONFIG_MAX_ACTIVE_REGIONS
167 /* Allow an architecture to set MAX_ACTIVE_REGIONS to save memory */
168 #define MAX_ACTIVE_REGIONS CONFIG_MAX_ACTIVE_REGIONS
170 #if MAX_NUMNODES >= 32
171 /* If there can be many nodes, allow up to 50 holes per node */
172 #define MAX_ACTIVE_REGIONS (MAX_NUMNODES*50)
174 /* By default, allow up to 256 distinct regions */
175 #define MAX_ACTIVE_REGIONS 256
179 static struct node_active_region __meminitdata early_node_map
[MAX_ACTIVE_REGIONS
];
180 static int __meminitdata nr_nodemap_entries
;
181 static unsigned long __meminitdata arch_zone_lowest_possible_pfn
[MAX_NR_ZONES
];
182 static unsigned long __meminitdata arch_zone_highest_possible_pfn
[MAX_NR_ZONES
];
183 static unsigned long __initdata required_kernelcore
;
184 static unsigned long __initdata required_movablecore
;
185 static unsigned long __meminitdata zone_movable_pfn
[MAX_NUMNODES
];
187 /* movable_zone is the "real" zone pages in ZONE_MOVABLE are taken from */
189 EXPORT_SYMBOL(movable_zone
);
190 #endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
193 int nr_node_ids __read_mostly
= MAX_NUMNODES
;
194 int nr_online_nodes __read_mostly
= 1;
195 EXPORT_SYMBOL(nr_node_ids
);
196 EXPORT_SYMBOL(nr_online_nodes
);
199 int page_group_by_mobility_disabled __read_mostly
;
201 static void set_pageblock_migratetype(struct page
*page
, int migratetype
)
204 if (unlikely(page_group_by_mobility_disabled
))
205 migratetype
= MIGRATE_UNMOVABLE
;
207 set_pageblock_flags_group(page
, (unsigned long)migratetype
,
208 PB_migrate
, PB_migrate_end
);
211 bool oom_killer_disabled __read_mostly
;
213 #ifdef CONFIG_DEBUG_VM
214 static int page_outside_zone_boundaries(struct zone
*zone
, struct page
*page
)
218 unsigned long pfn
= page_to_pfn(page
);
221 seq
= zone_span_seqbegin(zone
);
222 if (pfn
>= zone
->zone_start_pfn
+ zone
->spanned_pages
)
224 else if (pfn
< zone
->zone_start_pfn
)
226 } while (zone_span_seqretry(zone
, seq
));
231 static int page_is_consistent(struct zone
*zone
, struct page
*page
)
233 if (!pfn_valid_within(page_to_pfn(page
)))
235 if (zone
!= page_zone(page
))
241 * Temporary debugging check for pages not lying within a given zone.
243 static int bad_range(struct zone
*zone
, struct page
*page
)
245 if (page_outside_zone_boundaries(zone
, page
))
247 if (!page_is_consistent(zone
, page
))
253 static inline int bad_range(struct zone
*zone
, struct page
*page
)
259 static void bad_page(struct page
*page
)
261 static unsigned long resume
;
262 static unsigned long nr_shown
;
263 static unsigned long nr_unshown
;
265 /* Don't complain about poisoned pages */
266 if (PageHWPoison(page
)) {
267 __ClearPageBuddy(page
);
272 * Allow a burst of 60 reports, then keep quiet for that minute;
273 * or allow a steady drip of one report per second.
275 if (nr_shown
== 60) {
276 if (time_before(jiffies
, resume
)) {
282 "BUG: Bad page state: %lu messages suppressed\n",
289 resume
= jiffies
+ 60 * HZ
;
291 printk(KERN_ALERT
"BUG: Bad page state in process %s pfn:%05lx\n",
292 current
->comm
, page_to_pfn(page
));
297 /* Leave bad fields for debug, except PageBuddy could make trouble */
298 __ClearPageBuddy(page
);
299 add_taint(TAINT_BAD_PAGE
);
303 * Higher-order pages are called "compound pages". They are structured thusly:
305 * The first PAGE_SIZE page is called the "head page".
307 * The remaining PAGE_SIZE pages are called "tail pages".
309 * All pages have PG_compound set. All pages have their ->private pointing at
310 * the head page (even the head page has this).
312 * The first tail page's ->lru.next holds the address of the compound page's
313 * put_page() function. Its ->lru.prev holds the order of allocation.
314 * This usage means that zero-order pages may not be compound.
317 static void free_compound_page(struct page
*page
)
319 __free_pages_ok(page
, compound_order(page
));
322 void prep_compound_page(struct page
*page
, unsigned long order
)
325 int nr_pages
= 1 << order
;
327 set_compound_page_dtor(page
, free_compound_page
);
328 set_compound_order(page
, order
);
330 for (i
= 1; i
< nr_pages
; i
++) {
331 struct page
*p
= page
+ i
;
334 p
->first_page
= page
;
338 static int destroy_compound_page(struct page
*page
, unsigned long order
)
341 int nr_pages
= 1 << order
;
344 if (unlikely(compound_order(page
) != order
) ||
345 unlikely(!PageHead(page
))) {
350 __ClearPageHead(page
);
352 for (i
= 1; i
< nr_pages
; i
++) {
353 struct page
*p
= page
+ i
;
355 if (unlikely(!PageTail(p
) || (p
->first_page
!= page
))) {
365 static inline void prep_zero_page(struct page
*page
, int order
, gfp_t gfp_flags
)
370 * clear_highpage() will use KM_USER0, so it's a bug to use __GFP_ZERO
371 * and __GFP_HIGHMEM from hard or soft interrupt context.
373 VM_BUG_ON((gfp_flags
& __GFP_HIGHMEM
) && in_interrupt());
374 for (i
= 0; i
< (1 << order
); i
++)
375 clear_highpage(page
+ i
);
378 static inline void set_page_order(struct page
*page
, int order
)
380 set_page_private(page
, order
);
381 __SetPageBuddy(page
);
384 static inline void rmv_page_order(struct page
*page
)
386 __ClearPageBuddy(page
);
387 set_page_private(page
, 0);
391 * Locate the struct page for both the matching buddy in our
392 * pair (buddy1) and the combined O(n+1) page they form (page).
394 * 1) Any buddy B1 will have an order O twin B2 which satisfies
395 * the following equation:
397 * For example, if the starting buddy (buddy2) is #8 its order
399 * B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10
401 * 2) Any buddy B will have an order O+1 parent P which
402 * satisfies the following equation:
405 * Assumption: *_mem_map is contiguous at least up to MAX_ORDER
407 static inline struct page
*
408 __page_find_buddy(struct page
*page
, unsigned long page_idx
, unsigned int order
)
410 unsigned long buddy_idx
= page_idx
^ (1 << order
);
412 return page
+ (buddy_idx
- page_idx
);
415 static inline unsigned long
416 __find_combined_index(unsigned long page_idx
, unsigned int order
)
418 return (page_idx
& ~(1 << order
));
422 * This function checks whether a page is free && is the buddy
423 * we can do coalesce a page and its buddy if
424 * (a) the buddy is not in a hole &&
425 * (b) the buddy is in the buddy system &&
426 * (c) a page and its buddy have the same order &&
427 * (d) a page and its buddy are in the same zone.
429 * For recording whether a page is in the buddy system, we use PG_buddy.
430 * Setting, clearing, and testing PG_buddy is serialized by zone->lock.
432 * For recording page's order, we use page_private(page).
434 static inline int page_is_buddy(struct page
*page
, struct page
*buddy
,
437 if (!pfn_valid_within(page_to_pfn(buddy
)))
440 if (page_zone_id(page
) != page_zone_id(buddy
))
443 if (PageBuddy(buddy
) && page_order(buddy
) == order
) {
444 VM_BUG_ON(page_count(buddy
) != 0);
451 * Freeing function for a buddy system allocator.
453 * The concept of a buddy system is to maintain direct-mapped table
454 * (containing bit values) for memory blocks of various "orders".
455 * The bottom level table contains the map for the smallest allocatable
456 * units of memory (here, pages), and each level above it describes
457 * pairs of units from the levels below, hence, "buddies".
458 * At a high level, all that happens here is marking the table entry
459 * at the bottom level available, and propagating the changes upward
460 * as necessary, plus some accounting needed to play nicely with other
461 * parts of the VM system.
462 * At each level, we keep a list of pages, which are heads of continuous
463 * free pages of length of (1 << order) and marked with PG_buddy. Page's
464 * order is recorded in page_private(page) field.
465 * So when we are allocating or freeing one, we can derive the state of the
466 * other. That is, if we allocate a small block, and both were
467 * free, the remainder of the region must be split into blocks.
468 * If a block is freed, and its buddy is also free, then this
469 * triggers coalescing into a block of larger size.
474 static inline void __free_one_page(struct page
*page
,
475 struct zone
*zone
, unsigned int order
,
478 unsigned long page_idx
;
479 unsigned long combined_idx
;
482 if (unlikely(PageCompound(page
)))
483 if (unlikely(destroy_compound_page(page
, order
)))
486 VM_BUG_ON(migratetype
== -1);
488 page_idx
= page_to_pfn(page
) & ((1 << MAX_ORDER
) - 1);
490 VM_BUG_ON(page_idx
& ((1 << order
) - 1));
491 VM_BUG_ON(bad_range(zone
, page
));
493 while (order
< MAX_ORDER
-1) {
494 buddy
= __page_find_buddy(page
, page_idx
, order
);
495 if (!page_is_buddy(page
, buddy
, order
))
498 /* Our buddy is free, merge with it and move up one order. */
499 list_del(&buddy
->lru
);
500 zone
->free_area
[order
].nr_free
--;
501 rmv_page_order(buddy
);
502 combined_idx
= __find_combined_index(page_idx
, order
);
503 page
= page
+ (combined_idx
- page_idx
);
504 page_idx
= combined_idx
;
507 set_page_order(page
, order
);
510 * If this is not the largest possible page, check if the buddy
511 * of the next-highest order is free. If it is, it's possible
512 * that pages are being freed that will coalesce soon. In case,
513 * that is happening, add the free page to the tail of the list
514 * so it's less likely to be used soon and more likely to be merged
515 * as a higher order page
517 if ((order
< MAX_ORDER
-1) && pfn_valid_within(page_to_pfn(buddy
))) {
518 struct page
*higher_page
, *higher_buddy
;
519 combined_idx
= __find_combined_index(page_idx
, order
);
520 higher_page
= page
+ combined_idx
- page_idx
;
521 higher_buddy
= __page_find_buddy(higher_page
, combined_idx
, order
+ 1);
522 if (page_is_buddy(higher_page
, higher_buddy
, order
+ 1)) {
523 list_add_tail(&page
->lru
,
524 &zone
->free_area
[order
].free_list
[migratetype
]);
529 list_add(&page
->lru
, &zone
->free_area
[order
].free_list
[migratetype
]);
531 zone
->free_area
[order
].nr_free
++;
535 * free_page_mlock() -- clean up attempts to free and mlocked() page.
536 * Page should not be on lru, so no need to fix that up.
537 * free_pages_check() will verify...
539 static inline void free_page_mlock(struct page
*page
)
541 __dec_zone_page_state(page
, NR_MLOCK
);
542 __count_vm_event(UNEVICTABLE_MLOCKFREED
);
545 static inline int free_pages_check(struct page
*page
)
547 if (unlikely(page_mapcount(page
) |
548 (page
->mapping
!= NULL
) |
549 (atomic_read(&page
->_count
) != 0) |
550 (page
->flags
& PAGE_FLAGS_CHECK_AT_FREE
))) {
554 if (page
->flags
& PAGE_FLAGS_CHECK_AT_PREP
)
555 page
->flags
&= ~PAGE_FLAGS_CHECK_AT_PREP
;
560 * Frees a number of pages from the PCP lists
561 * Assumes all pages on list are in same zone, and of same order.
562 * count is the number of pages to free.
564 * If the zone was previously in an "all pages pinned" state then look to
565 * see if this freeing clears that state.
567 * And clear the zone's pages_scanned counter, to hold off the "all pages are
568 * pinned" detection logic.
570 static void free_pcppages_bulk(struct zone
*zone
, int count
,
571 struct per_cpu_pages
*pcp
)
576 spin_lock(&zone
->lock
);
577 zone
->all_unreclaimable
= 0;
578 zone
->pages_scanned
= 0;
580 __mod_zone_page_state(zone
, NR_FREE_PAGES
, count
);
583 struct list_head
*list
;
586 * Remove pages from lists in a round-robin fashion. A
587 * batch_free count is maintained that is incremented when an
588 * empty list is encountered. This is so more pages are freed
589 * off fuller lists instead of spinning excessively around empty
594 if (++migratetype
== MIGRATE_PCPTYPES
)
596 list
= &pcp
->lists
[migratetype
];
597 } while (list_empty(list
));
600 page
= list_entry(list
->prev
, struct page
, lru
);
601 /* must delete as __free_one_page list manipulates */
602 list_del(&page
->lru
);
603 /* MIGRATE_MOVABLE list may include MIGRATE_RESERVEs */
604 __free_one_page(page
, zone
, 0, page_private(page
));
605 trace_mm_page_pcpu_drain(page
, 0, page_private(page
));
606 } while (--count
&& --batch_free
&& !list_empty(list
));
608 spin_unlock(&zone
->lock
);
611 static void free_one_page(struct zone
*zone
, struct page
*page
, int order
,
614 spin_lock(&zone
->lock
);
615 zone
->all_unreclaimable
= 0;
616 zone
->pages_scanned
= 0;
618 __mod_zone_page_state(zone
, NR_FREE_PAGES
, 1 << order
);
619 __free_one_page(page
, zone
, order
, migratetype
);
620 spin_unlock(&zone
->lock
);
623 static void __free_pages_ok(struct page
*page
, unsigned int order
)
628 int wasMlocked
= __TestClearPageMlocked(page
);
630 trace_mm_page_free_direct(page
, order
);
631 kmemcheck_free_shadow(page
, order
);
633 for (i
= 0 ; i
< (1 << order
) ; ++i
)
634 bad
+= free_pages_check(page
+ i
);
638 if (!PageHighMem(page
)) {
639 debug_check_no_locks_freed(page_address(page
),PAGE_SIZE
<<order
);
640 debug_check_no_obj_freed(page_address(page
),
643 arch_free_page(page
, order
);
644 kernel_map_pages(page
, 1 << order
, 0);
646 local_irq_save(flags
);
647 if (unlikely(wasMlocked
))
648 free_page_mlock(page
);
649 __count_vm_events(PGFREE
, 1 << order
);
650 free_one_page(page_zone(page
), page
, order
,
651 get_pageblock_migratetype(page
));
652 local_irq_restore(flags
);
656 * permit the bootmem allocator to evade page validation on high-order frees
658 void __meminit
__free_pages_bootmem(struct page
*page
, unsigned int order
)
661 __ClearPageReserved(page
);
662 set_page_count(page
, 0);
663 set_page_refcounted(page
);
669 for (loop
= 0; loop
< BITS_PER_LONG
; loop
++) {
670 struct page
*p
= &page
[loop
];
672 if (loop
+ 1 < BITS_PER_LONG
)
674 __ClearPageReserved(p
);
675 set_page_count(p
, 0);
678 set_page_refcounted(page
);
679 __free_pages(page
, order
);
685 * The order of subdivision here is critical for the IO subsystem.
686 * Please do not alter this order without good reasons and regression
687 * testing. Specifically, as large blocks of memory are subdivided,
688 * the order in which smaller blocks are delivered depends on the order
689 * they're subdivided in this function. This is the primary factor
690 * influencing the order in which pages are delivered to the IO
691 * subsystem according to empirical testing, and this is also justified
692 * by considering the behavior of a buddy system containing a single
693 * large block of memory acted on by a series of small allocations.
694 * This behavior is a critical factor in sglist merging's success.
698 static inline void expand(struct zone
*zone
, struct page
*page
,
699 int low
, int high
, struct free_area
*area
,
702 unsigned long size
= 1 << high
;
708 VM_BUG_ON(bad_range(zone
, &page
[size
]));
709 list_add(&page
[size
].lru
, &area
->free_list
[migratetype
]);
711 set_page_order(&page
[size
], high
);
716 * This page is about to be returned from the page allocator
718 static inline int check_new_page(struct page
*page
)
720 if (unlikely(page_mapcount(page
) |
721 (page
->mapping
!= NULL
) |
722 (atomic_read(&page
->_count
) != 0) |
723 (page
->flags
& PAGE_FLAGS_CHECK_AT_PREP
))) {
730 static int prep_new_page(struct page
*page
, int order
, gfp_t gfp_flags
)
734 for (i
= 0; i
< (1 << order
); i
++) {
735 struct page
*p
= page
+ i
;
736 if (unlikely(check_new_page(p
)))
740 set_page_private(page
, 0);
741 set_page_refcounted(page
);
743 arch_alloc_page(page
, order
);
744 kernel_map_pages(page
, 1 << order
, 1);
746 if (gfp_flags
& __GFP_ZERO
)
747 prep_zero_page(page
, order
, gfp_flags
);
749 if (order
&& (gfp_flags
& __GFP_COMP
))
750 prep_compound_page(page
, order
);
756 * Go through the free lists for the given migratetype and remove
757 * the smallest available page from the freelists
760 struct page
*__rmqueue_smallest(struct zone
*zone
, unsigned int order
,
763 unsigned int current_order
;
764 struct free_area
* area
;
767 /* Find a page of the appropriate size in the preferred list */
768 for (current_order
= order
; current_order
< MAX_ORDER
; ++current_order
) {
769 area
= &(zone
->free_area
[current_order
]);
770 if (list_empty(&area
->free_list
[migratetype
]))
773 page
= list_entry(area
->free_list
[migratetype
].next
,
775 list_del(&page
->lru
);
776 rmv_page_order(page
);
778 expand(zone
, page
, order
, current_order
, area
, migratetype
);
787 * This array describes the order lists are fallen back to when
788 * the free lists for the desirable migrate type are depleted
790 static int fallbacks
[MIGRATE_TYPES
][MIGRATE_TYPES
-1] = {
791 [MIGRATE_UNMOVABLE
] = { MIGRATE_RECLAIMABLE
, MIGRATE_MOVABLE
, MIGRATE_RESERVE
},
792 [MIGRATE_RECLAIMABLE
] = { MIGRATE_UNMOVABLE
, MIGRATE_MOVABLE
, MIGRATE_RESERVE
},
793 [MIGRATE_MOVABLE
] = { MIGRATE_RECLAIMABLE
, MIGRATE_UNMOVABLE
, MIGRATE_RESERVE
},
794 [MIGRATE_RESERVE
] = { MIGRATE_RESERVE
, MIGRATE_RESERVE
, MIGRATE_RESERVE
}, /* Never used */
798 * Move the free pages in a range to the free lists of the requested type.
799 * Note that start_page and end_pages are not aligned on a pageblock
800 * boundary. If alignment is required, use move_freepages_block()
802 static int move_freepages(struct zone
*zone
,
803 struct page
*start_page
, struct page
*end_page
,
810 #ifndef CONFIG_HOLES_IN_ZONE
812 * page_zone is not safe to call in this context when
813 * CONFIG_HOLES_IN_ZONE is set. This bug check is probably redundant
814 * anyway as we check zone boundaries in move_freepages_block().
815 * Remove at a later date when no bug reports exist related to
816 * grouping pages by mobility
818 BUG_ON(page_zone(start_page
) != page_zone(end_page
));
821 for (page
= start_page
; page
<= end_page
;) {
822 /* Make sure we are not inadvertently changing nodes */
823 VM_BUG_ON(page_to_nid(page
) != zone_to_nid(zone
));
825 if (!pfn_valid_within(page_to_pfn(page
))) {
830 if (!PageBuddy(page
)) {
835 order
= page_order(page
);
836 list_del(&page
->lru
);
838 &zone
->free_area
[order
].free_list
[migratetype
]);
840 pages_moved
+= 1 << order
;
846 static int move_freepages_block(struct zone
*zone
, struct page
*page
,
849 unsigned long start_pfn
, end_pfn
;
850 struct page
*start_page
, *end_page
;
852 start_pfn
= page_to_pfn(page
);
853 start_pfn
= start_pfn
& ~(pageblock_nr_pages
-1);
854 start_page
= pfn_to_page(start_pfn
);
855 end_page
= start_page
+ pageblock_nr_pages
- 1;
856 end_pfn
= start_pfn
+ pageblock_nr_pages
- 1;
858 /* Do not cross zone boundaries */
859 if (start_pfn
< zone
->zone_start_pfn
)
861 if (end_pfn
>= zone
->zone_start_pfn
+ zone
->spanned_pages
)
864 return move_freepages(zone
, start_page
, end_page
, migratetype
);
867 static void change_pageblock_range(struct page
*pageblock_page
,
868 int start_order
, int migratetype
)
870 int nr_pageblocks
= 1 << (start_order
- pageblock_order
);
872 while (nr_pageblocks
--) {
873 set_pageblock_migratetype(pageblock_page
, migratetype
);
874 pageblock_page
+= pageblock_nr_pages
;
878 /* Remove an element from the buddy allocator from the fallback list */
879 static inline struct page
*
880 __rmqueue_fallback(struct zone
*zone
, int order
, int start_migratetype
)
882 struct free_area
* area
;
887 /* Find the largest possible block of pages in the other list */
888 for (current_order
= MAX_ORDER
-1; current_order
>= order
;
890 for (i
= 0; i
< MIGRATE_TYPES
- 1; i
++) {
891 migratetype
= fallbacks
[start_migratetype
][i
];
893 /* MIGRATE_RESERVE handled later if necessary */
894 if (migratetype
== MIGRATE_RESERVE
)
897 area
= &(zone
->free_area
[current_order
]);
898 if (list_empty(&area
->free_list
[migratetype
]))
901 page
= list_entry(area
->free_list
[migratetype
].next
,
906 * If breaking a large block of pages, move all free
907 * pages to the preferred allocation list. If falling
908 * back for a reclaimable kernel allocation, be more
909 * agressive about taking ownership of free pages
911 if (unlikely(current_order
>= (pageblock_order
>> 1)) ||
912 start_migratetype
== MIGRATE_RECLAIMABLE
||
913 page_group_by_mobility_disabled
) {
915 pages
= move_freepages_block(zone
, page
,
918 /* Claim the whole block if over half of it is free */
919 if (pages
>= (1 << (pageblock_order
-1)) ||
920 page_group_by_mobility_disabled
)
921 set_pageblock_migratetype(page
,
924 migratetype
= start_migratetype
;
927 /* Remove the page from the freelists */
928 list_del(&page
->lru
);
929 rmv_page_order(page
);
931 /* Take ownership for orders >= pageblock_order */
932 if (current_order
>= pageblock_order
)
933 change_pageblock_range(page
, current_order
,
936 expand(zone
, page
, order
, current_order
, area
, migratetype
);
938 trace_mm_page_alloc_extfrag(page
, order
, current_order
,
939 start_migratetype
, migratetype
);
949 * Do the hard work of removing an element from the buddy allocator.
950 * Call me with the zone->lock already held.
952 static struct page
*__rmqueue(struct zone
*zone
, unsigned int order
,
958 page
= __rmqueue_smallest(zone
, order
, migratetype
);
960 if (unlikely(!page
) && migratetype
!= MIGRATE_RESERVE
) {
961 page
= __rmqueue_fallback(zone
, order
, migratetype
);
964 * Use MIGRATE_RESERVE rather than fail an allocation. goto
965 * is used because __rmqueue_smallest is an inline function
966 * and we want just one call site
969 migratetype
= MIGRATE_RESERVE
;
974 trace_mm_page_alloc_zone_locked(page
, order
, migratetype
);
979 * Obtain a specified number of elements from the buddy allocator, all under
980 * a single hold of the lock, for efficiency. Add them to the supplied list.
981 * Returns the number of new pages which were placed at *list.
983 static int rmqueue_bulk(struct zone
*zone
, unsigned int order
,
984 unsigned long count
, struct list_head
*list
,
985 int migratetype
, int cold
)
989 spin_lock(&zone
->lock
);
990 for (i
= 0; i
< count
; ++i
) {
991 struct page
*page
= __rmqueue(zone
, order
, migratetype
);
992 if (unlikely(page
== NULL
))
996 * Split buddy pages returned by expand() are received here
997 * in physical page order. The page is added to the callers and
998 * list and the list head then moves forward. From the callers
999 * perspective, the linked list is ordered by page number in
1000 * some conditions. This is useful for IO devices that can
1001 * merge IO requests if the physical pages are ordered
1004 if (likely(cold
== 0))
1005 list_add(&page
->lru
, list
);
1007 list_add_tail(&page
->lru
, list
);
1008 set_page_private(page
, migratetype
);
1011 __mod_zone_page_state(zone
, NR_FREE_PAGES
, -(i
<< order
));
1012 spin_unlock(&zone
->lock
);
1018 * Called from the vmstat counter updater to drain pagesets of this
1019 * currently executing processor on remote nodes after they have
1022 * Note that this function must be called with the thread pinned to
1023 * a single processor.
1025 void drain_zone_pages(struct zone
*zone
, struct per_cpu_pages
*pcp
)
1027 unsigned long flags
;
1030 local_irq_save(flags
);
1031 if (pcp
->count
>= pcp
->batch
)
1032 to_drain
= pcp
->batch
;
1034 to_drain
= pcp
->count
;
1035 free_pcppages_bulk(zone
, to_drain
, pcp
);
1036 pcp
->count
-= to_drain
;
1037 local_irq_restore(flags
);
1042 * Drain pages of the indicated processor.
1044 * The processor must either be the current processor and the
1045 * thread pinned to the current processor or a processor that
1048 static void drain_pages(unsigned int cpu
)
1050 unsigned long flags
;
1053 for_each_populated_zone(zone
) {
1054 struct per_cpu_pageset
*pset
;
1055 struct per_cpu_pages
*pcp
;
1057 local_irq_save(flags
);
1058 pset
= per_cpu_ptr(zone
->pageset
, cpu
);
1061 free_pcppages_bulk(zone
, pcp
->count
, pcp
);
1063 local_irq_restore(flags
);
1068 * Spill all of this CPU's per-cpu pages back into the buddy allocator.
1070 void drain_local_pages(void *arg
)
1072 drain_pages(smp_processor_id());
1076 * Spill all the per-cpu pages from all CPUs back into the buddy allocator
1078 void drain_all_pages(void)
1080 on_each_cpu(drain_local_pages
, NULL
, 1);
1083 #ifdef CONFIG_HIBERNATION
1085 void mark_free_pages(struct zone
*zone
)
1087 unsigned long pfn
, max_zone_pfn
;
1088 unsigned long flags
;
1090 struct list_head
*curr
;
1092 if (!zone
->spanned_pages
)
1095 spin_lock_irqsave(&zone
->lock
, flags
);
1097 max_zone_pfn
= zone
->zone_start_pfn
+ zone
->spanned_pages
;
1098 for (pfn
= zone
->zone_start_pfn
; pfn
< max_zone_pfn
; pfn
++)
1099 if (pfn_valid(pfn
)) {
1100 struct page
*page
= pfn_to_page(pfn
);
1102 if (!swsusp_page_is_forbidden(page
))
1103 swsusp_unset_page_free(page
);
1106 for_each_migratetype_order(order
, t
) {
1107 list_for_each(curr
, &zone
->free_area
[order
].free_list
[t
]) {
1110 pfn
= page_to_pfn(list_entry(curr
, struct page
, lru
));
1111 for (i
= 0; i
< (1UL << order
); i
++)
1112 swsusp_set_page_free(pfn_to_page(pfn
+ i
));
1115 spin_unlock_irqrestore(&zone
->lock
, flags
);
1117 #endif /* CONFIG_PM */
1120 * Free a 0-order page
1121 * cold == 1 ? free a cold page : free a hot page
1123 void free_hot_cold_page(struct page
*page
, int cold
)
1125 struct zone
*zone
= page_zone(page
);
1126 struct per_cpu_pages
*pcp
;
1127 unsigned long flags
;
1129 int wasMlocked
= __TestClearPageMlocked(page
);
1131 trace_mm_page_free_direct(page
, 0);
1132 kmemcheck_free_shadow(page
, 0);
1135 page
->mapping
= NULL
;
1136 if (free_pages_check(page
))
1139 if (!PageHighMem(page
)) {
1140 debug_check_no_locks_freed(page_address(page
), PAGE_SIZE
);
1141 debug_check_no_obj_freed(page_address(page
), PAGE_SIZE
);
1143 arch_free_page(page
, 0);
1144 kernel_map_pages(page
, 1, 0);
1146 migratetype
= get_pageblock_migratetype(page
);
1147 set_page_private(page
, migratetype
);
1148 local_irq_save(flags
);
1149 if (unlikely(wasMlocked
))
1150 free_page_mlock(page
);
1151 __count_vm_event(PGFREE
);
1154 * We only track unmovable, reclaimable and movable on pcp lists.
1155 * Free ISOLATE pages back to the allocator because they are being
1156 * offlined but treat RESERVE as movable pages so we can get those
1157 * areas back if necessary. Otherwise, we may have to free
1158 * excessively into the page allocator
1160 if (migratetype
>= MIGRATE_PCPTYPES
) {
1161 if (unlikely(migratetype
== MIGRATE_ISOLATE
)) {
1162 free_one_page(zone
, page
, 0, migratetype
);
1165 migratetype
= MIGRATE_MOVABLE
;
1168 pcp
= &this_cpu_ptr(zone
->pageset
)->pcp
;
1170 list_add_tail(&page
->lru
, &pcp
->lists
[migratetype
]);
1172 list_add(&page
->lru
, &pcp
->lists
[migratetype
]);
1174 if (pcp
->count
>= pcp
->high
) {
1175 free_pcppages_bulk(zone
, pcp
->batch
, pcp
);
1176 pcp
->count
-= pcp
->batch
;
1180 local_irq_restore(flags
);
1184 * split_page takes a non-compound higher-order page, and splits it into
1185 * n (1<<order) sub-pages: page[0..n]
1186 * Each sub-page must be freed individually.
1188 * Note: this is probably too low level an operation for use in drivers.
1189 * Please consult with lkml before using this in your driver.
1191 void split_page(struct page
*page
, unsigned int order
)
1195 VM_BUG_ON(PageCompound(page
));
1196 VM_BUG_ON(!page_count(page
));
1198 #ifdef CONFIG_KMEMCHECK
1200 * Split shadow pages too, because free(page[0]) would
1201 * otherwise free the whole shadow.
1203 if (kmemcheck_page_is_tracked(page
))
1204 split_page(virt_to_page(page
[0].shadow
), order
);
1207 for (i
= 1; i
< (1 << order
); i
++)
1208 set_page_refcounted(page
+ i
);
1212 * Similar to split_page except the page is already free. As this is only
1213 * being used for migration, the migratetype of the block also changes.
1214 * As this is called with interrupts disabled, the caller is responsible
1215 * for calling arch_alloc_page() and kernel_map_page() after interrupts
1218 * Note: this is probably too low level an operation for use in drivers.
1219 * Please consult with lkml before using this in your driver.
1221 int split_free_page(struct page
*page
)
1224 unsigned long watermark
;
1227 BUG_ON(!PageBuddy(page
));
1229 zone
= page_zone(page
);
1230 order
= page_order(page
);
1232 /* Obey watermarks as if the page was being allocated */
1233 watermark
= low_wmark_pages(zone
) + (1 << order
);
1234 if (!zone_watermark_ok(zone
, 0, watermark
, 0, 0))
1237 /* Remove page from free list */
1238 list_del(&page
->lru
);
1239 zone
->free_area
[order
].nr_free
--;
1240 rmv_page_order(page
);
1241 __mod_zone_page_state(zone
, NR_FREE_PAGES
, -(1UL << order
));
1243 /* Split into individual pages */
1244 set_page_refcounted(page
);
1245 split_page(page
, order
);
1247 if (order
>= pageblock_order
- 1) {
1248 struct page
*endpage
= page
+ (1 << order
) - 1;
1249 for (; page
< endpage
; page
+= pageblock_nr_pages
)
1250 set_pageblock_migratetype(page
, MIGRATE_MOVABLE
);
1257 * Really, prep_compound_page() should be called from __rmqueue_bulk(). But
1258 * we cheat by calling it from here, in the order > 0 path. Saves a branch
1262 struct page
*buffered_rmqueue(struct zone
*preferred_zone
,
1263 struct zone
*zone
, int order
, gfp_t gfp_flags
,
1266 unsigned long flags
;
1268 int cold
= !!(gfp_flags
& __GFP_COLD
);
1271 if (likely(order
== 0)) {
1272 struct per_cpu_pages
*pcp
;
1273 struct list_head
*list
;
1275 local_irq_save(flags
);
1276 pcp
= &this_cpu_ptr(zone
->pageset
)->pcp
;
1277 list
= &pcp
->lists
[migratetype
];
1278 if (list_empty(list
)) {
1279 pcp
->count
+= rmqueue_bulk(zone
, 0,
1282 if (unlikely(list_empty(list
)))
1287 page
= list_entry(list
->prev
, struct page
, lru
);
1289 page
= list_entry(list
->next
, struct page
, lru
);
1291 list_del(&page
->lru
);
1294 if (unlikely(gfp_flags
& __GFP_NOFAIL
)) {
1296 * __GFP_NOFAIL is not to be used in new code.
1298 * All __GFP_NOFAIL callers should be fixed so that they
1299 * properly detect and handle allocation failures.
1301 * We most definitely don't want callers attempting to
1302 * allocate greater than order-1 page units with
1305 WARN_ON_ONCE(order
> 1);
1307 spin_lock_irqsave(&zone
->lock
, flags
);
1308 page
= __rmqueue(zone
, order
, migratetype
);
1309 spin_unlock(&zone
->lock
);
1312 __mod_zone_page_state(zone
, NR_FREE_PAGES
, -(1 << order
));
1315 __count_zone_vm_events(PGALLOC
, zone
, 1 << order
);
1316 zone_statistics(preferred_zone
, zone
);
1317 local_irq_restore(flags
);
1319 VM_BUG_ON(bad_range(zone
, page
));
1320 if (prep_new_page(page
, order
, gfp_flags
))
1325 local_irq_restore(flags
);
1329 /* The ALLOC_WMARK bits are used as an index to zone->watermark */
1330 #define ALLOC_WMARK_MIN WMARK_MIN
1331 #define ALLOC_WMARK_LOW WMARK_LOW
1332 #define ALLOC_WMARK_HIGH WMARK_HIGH
1333 #define ALLOC_NO_WATERMARKS 0x04 /* don't check watermarks at all */
1335 /* Mask to get the watermark bits */
1336 #define ALLOC_WMARK_MASK (ALLOC_NO_WATERMARKS-1)
1338 #define ALLOC_HARDER 0x10 /* try to alloc harder */
1339 #define ALLOC_HIGH 0x20 /* __GFP_HIGH set */
1340 #define ALLOC_CPUSET 0x40 /* check for correct cpuset */
1342 #ifdef CONFIG_FAIL_PAGE_ALLOC
1344 static struct fail_page_alloc_attr
{
1345 struct fault_attr attr
;
1347 u32 ignore_gfp_highmem
;
1348 u32 ignore_gfp_wait
;
1351 #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
1353 struct dentry
*ignore_gfp_highmem_file
;
1354 struct dentry
*ignore_gfp_wait_file
;
1355 struct dentry
*min_order_file
;
1357 #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
1359 } fail_page_alloc
= {
1360 .attr
= FAULT_ATTR_INITIALIZER
,
1361 .ignore_gfp_wait
= 1,
1362 .ignore_gfp_highmem
= 1,
1366 static int __init
setup_fail_page_alloc(char *str
)
1368 return setup_fault_attr(&fail_page_alloc
.attr
, str
);
1370 __setup("fail_page_alloc=", setup_fail_page_alloc
);
1372 static int should_fail_alloc_page(gfp_t gfp_mask
, unsigned int order
)
1374 if (order
< fail_page_alloc
.min_order
)
1376 if (gfp_mask
& __GFP_NOFAIL
)
1378 if (fail_page_alloc
.ignore_gfp_highmem
&& (gfp_mask
& __GFP_HIGHMEM
))
1380 if (fail_page_alloc
.ignore_gfp_wait
&& (gfp_mask
& __GFP_WAIT
))
1383 return should_fail(&fail_page_alloc
.attr
, 1 << order
);
1386 #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
1388 static int __init
fail_page_alloc_debugfs(void)
1390 mode_t mode
= S_IFREG
| S_IRUSR
| S_IWUSR
;
1394 err
= init_fault_attr_dentries(&fail_page_alloc
.attr
,
1398 dir
= fail_page_alloc
.attr
.dentries
.dir
;
1400 fail_page_alloc
.ignore_gfp_wait_file
=
1401 debugfs_create_bool("ignore-gfp-wait", mode
, dir
,
1402 &fail_page_alloc
.ignore_gfp_wait
);
1404 fail_page_alloc
.ignore_gfp_highmem_file
=
1405 debugfs_create_bool("ignore-gfp-highmem", mode
, dir
,
1406 &fail_page_alloc
.ignore_gfp_highmem
);
1407 fail_page_alloc
.min_order_file
=
1408 debugfs_create_u32("min-order", mode
, dir
,
1409 &fail_page_alloc
.min_order
);
1411 if (!fail_page_alloc
.ignore_gfp_wait_file
||
1412 !fail_page_alloc
.ignore_gfp_highmem_file
||
1413 !fail_page_alloc
.min_order_file
) {
1415 debugfs_remove(fail_page_alloc
.ignore_gfp_wait_file
);
1416 debugfs_remove(fail_page_alloc
.ignore_gfp_highmem_file
);
1417 debugfs_remove(fail_page_alloc
.min_order_file
);
1418 cleanup_fault_attr_dentries(&fail_page_alloc
.attr
);
1424 late_initcall(fail_page_alloc_debugfs
);
1426 #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
1428 #else /* CONFIG_FAIL_PAGE_ALLOC */
1430 static inline int should_fail_alloc_page(gfp_t gfp_mask
, unsigned int order
)
1435 #endif /* CONFIG_FAIL_PAGE_ALLOC */
1438 * Return 1 if free pages are above 'mark'. This takes into account the order
1439 * of the allocation.
1441 int zone_watermark_ok(struct zone
*z
, int order
, unsigned long mark
,
1442 int classzone_idx
, int alloc_flags
)
1444 /* free_pages my go negative - that's OK */
1446 long free_pages
= zone_page_state(z
, NR_FREE_PAGES
) - (1 << order
) + 1;
1449 if (alloc_flags
& ALLOC_HIGH
)
1451 if (alloc_flags
& ALLOC_HARDER
)
1454 if (free_pages
<= min
+ z
->lowmem_reserve
[classzone_idx
])
1456 for (o
= 0; o
< order
; o
++) {
1457 /* At the next order, this order's pages become unavailable */
1458 free_pages
-= z
->free_area
[o
].nr_free
<< o
;
1460 /* Require fewer higher order pages to be free */
1463 if (free_pages
<= min
)
1471 * zlc_setup - Setup for "zonelist cache". Uses cached zone data to
1472 * skip over zones that are not allowed by the cpuset, or that have
1473 * been recently (in last second) found to be nearly full. See further
1474 * comments in mmzone.h. Reduces cache footprint of zonelist scans
1475 * that have to skip over a lot of full or unallowed zones.
1477 * If the zonelist cache is present in the passed in zonelist, then
1478 * returns a pointer to the allowed node mask (either the current
1479 * tasks mems_allowed, or node_states[N_HIGH_MEMORY].)
1481 * If the zonelist cache is not available for this zonelist, does
1482 * nothing and returns NULL.
1484 * If the fullzones BITMAP in the zonelist cache is stale (more than
1485 * a second since last zap'd) then we zap it out (clear its bits.)
1487 * We hold off even calling zlc_setup, until after we've checked the
1488 * first zone in the zonelist, on the theory that most allocations will
1489 * be satisfied from that first zone, so best to examine that zone as
1490 * quickly as we can.
1492 static nodemask_t
*zlc_setup(struct zonelist
*zonelist
, int alloc_flags
)
1494 struct zonelist_cache
*zlc
; /* cached zonelist speedup info */
1495 nodemask_t
*allowednodes
; /* zonelist_cache approximation */
1497 zlc
= zonelist
->zlcache_ptr
;
1501 if (time_after(jiffies
, zlc
->last_full_zap
+ HZ
)) {
1502 bitmap_zero(zlc
->fullzones
, MAX_ZONES_PER_ZONELIST
);
1503 zlc
->last_full_zap
= jiffies
;
1506 allowednodes
= !in_interrupt() && (alloc_flags
& ALLOC_CPUSET
) ?
1507 &cpuset_current_mems_allowed
:
1508 &node_states
[N_HIGH_MEMORY
];
1509 return allowednodes
;
1513 * Given 'z' scanning a zonelist, run a couple of quick checks to see
1514 * if it is worth looking at further for free memory:
1515 * 1) Check that the zone isn't thought to be full (doesn't have its
1516 * bit set in the zonelist_cache fullzones BITMAP).
1517 * 2) Check that the zones node (obtained from the zonelist_cache
1518 * z_to_n[] mapping) is allowed in the passed in allowednodes mask.
1519 * Return true (non-zero) if zone is worth looking at further, or
1520 * else return false (zero) if it is not.
1522 * This check -ignores- the distinction between various watermarks,
1523 * such as GFP_HIGH, GFP_ATOMIC, PF_MEMALLOC, ... If a zone is
1524 * found to be full for any variation of these watermarks, it will
1525 * be considered full for up to one second by all requests, unless
1526 * we are so low on memory on all allowed nodes that we are forced
1527 * into the second scan of the zonelist.
1529 * In the second scan we ignore this zonelist cache and exactly
1530 * apply the watermarks to all zones, even it is slower to do so.
1531 * We are low on memory in the second scan, and should leave no stone
1532 * unturned looking for a free page.
1534 static int zlc_zone_worth_trying(struct zonelist
*zonelist
, struct zoneref
*z
,
1535 nodemask_t
*allowednodes
)
1537 struct zonelist_cache
*zlc
; /* cached zonelist speedup info */
1538 int i
; /* index of *z in zonelist zones */
1539 int n
; /* node that zone *z is on */
1541 zlc
= zonelist
->zlcache_ptr
;
1545 i
= z
- zonelist
->_zonerefs
;
1548 /* This zone is worth trying if it is allowed but not full */
1549 return node_isset(n
, *allowednodes
) && !test_bit(i
, zlc
->fullzones
);
1553 * Given 'z' scanning a zonelist, set the corresponding bit in
1554 * zlc->fullzones, so that subsequent attempts to allocate a page
1555 * from that zone don't waste time re-examining it.
1557 static void zlc_mark_zone_full(struct zonelist
*zonelist
, struct zoneref
*z
)
1559 struct zonelist_cache
*zlc
; /* cached zonelist speedup info */
1560 int i
; /* index of *z in zonelist zones */
1562 zlc
= zonelist
->zlcache_ptr
;
1566 i
= z
- zonelist
->_zonerefs
;
1568 set_bit(i
, zlc
->fullzones
);
1571 #else /* CONFIG_NUMA */
1573 static nodemask_t
*zlc_setup(struct zonelist
*zonelist
, int alloc_flags
)
1578 static int zlc_zone_worth_trying(struct zonelist
*zonelist
, struct zoneref
*z
,
1579 nodemask_t
*allowednodes
)
1584 static void zlc_mark_zone_full(struct zonelist
*zonelist
, struct zoneref
*z
)
1587 #endif /* CONFIG_NUMA */
1590 * get_page_from_freelist goes through the zonelist trying to allocate
1593 static struct page
*
1594 get_page_from_freelist(gfp_t gfp_mask
, nodemask_t
*nodemask
, unsigned int order
,
1595 struct zonelist
*zonelist
, int high_zoneidx
, int alloc_flags
,
1596 struct zone
*preferred_zone
, int migratetype
)
1599 struct page
*page
= NULL
;
1602 nodemask_t
*allowednodes
= NULL
;/* zonelist_cache approximation */
1603 int zlc_active
= 0; /* set if using zonelist_cache */
1604 int did_zlc_setup
= 0; /* just call zlc_setup() one time */
1606 classzone_idx
= zone_idx(preferred_zone
);
1609 * Scan zonelist, looking for a zone with enough free.
1610 * See also cpuset_zone_allowed() comment in kernel/cpuset.c.
1612 for_each_zone_zonelist_nodemask(zone
, z
, zonelist
,
1613 high_zoneidx
, nodemask
) {
1614 if (NUMA_BUILD
&& zlc_active
&&
1615 !zlc_zone_worth_trying(zonelist
, z
, allowednodes
))
1617 if ((alloc_flags
& ALLOC_CPUSET
) &&
1618 !cpuset_zone_allowed_softwall(zone
, gfp_mask
))
1621 BUILD_BUG_ON(ALLOC_NO_WATERMARKS
< NR_WMARK
);
1622 if (!(alloc_flags
& ALLOC_NO_WATERMARKS
)) {
1626 mark
= zone
->watermark
[alloc_flags
& ALLOC_WMARK_MASK
];
1627 if (zone_watermark_ok(zone
, order
, mark
,
1628 classzone_idx
, alloc_flags
))
1631 if (zone_reclaim_mode
== 0)
1632 goto this_zone_full
;
1634 ret
= zone_reclaim(zone
, gfp_mask
, order
);
1636 case ZONE_RECLAIM_NOSCAN
:
1639 case ZONE_RECLAIM_FULL
:
1640 /* scanned but unreclaimable */
1641 goto this_zone_full
;
1643 /* did we reclaim enough */
1644 if (!zone_watermark_ok(zone
, order
, mark
,
1645 classzone_idx
, alloc_flags
))
1646 goto this_zone_full
;
1651 page
= buffered_rmqueue(preferred_zone
, zone
, order
,
1652 gfp_mask
, migratetype
);
1657 zlc_mark_zone_full(zonelist
, z
);
1659 if (NUMA_BUILD
&& !did_zlc_setup
&& nr_online_nodes
> 1) {
1661 * we do zlc_setup after the first zone is tried but only
1662 * if there are multiple nodes make it worthwhile
1664 allowednodes
= zlc_setup(zonelist
, alloc_flags
);
1670 if (unlikely(NUMA_BUILD
&& page
== NULL
&& zlc_active
)) {
1671 /* Disable zlc cache for second zonelist scan */
1679 should_alloc_retry(gfp_t gfp_mask
, unsigned int order
,
1680 unsigned long pages_reclaimed
)
1682 /* Do not loop if specifically requested */
1683 if (gfp_mask
& __GFP_NORETRY
)
1687 * In this implementation, order <= PAGE_ALLOC_COSTLY_ORDER
1688 * means __GFP_NOFAIL, but that may not be true in other
1691 if (order
<= PAGE_ALLOC_COSTLY_ORDER
)
1695 * For order > PAGE_ALLOC_COSTLY_ORDER, if __GFP_REPEAT is
1696 * specified, then we retry until we no longer reclaim any pages
1697 * (above), or we've reclaimed an order of pages at least as
1698 * large as the allocation's order. In both cases, if the
1699 * allocation still fails, we stop retrying.
1701 if (gfp_mask
& __GFP_REPEAT
&& pages_reclaimed
< (1 << order
))
1705 * Don't let big-order allocations loop unless the caller
1706 * explicitly requests that.
1708 if (gfp_mask
& __GFP_NOFAIL
)
1714 static inline struct page
*
1715 __alloc_pages_may_oom(gfp_t gfp_mask
, unsigned int order
,
1716 struct zonelist
*zonelist
, enum zone_type high_zoneidx
,
1717 nodemask_t
*nodemask
, struct zone
*preferred_zone
,
1722 /* Acquire the OOM killer lock for the zones in zonelist */
1723 if (!try_set_zone_oom(zonelist
, gfp_mask
)) {
1724 schedule_timeout_uninterruptible(1);
1729 * Go through the zonelist yet one more time, keep very high watermark
1730 * here, this is only to catch a parallel oom killing, we must fail if
1731 * we're still under heavy pressure.
1733 page
= get_page_from_freelist(gfp_mask
|__GFP_HARDWALL
, nodemask
,
1734 order
, zonelist
, high_zoneidx
,
1735 ALLOC_WMARK_HIGH
|ALLOC_CPUSET
,
1736 preferred_zone
, migratetype
);
1740 if (!(gfp_mask
& __GFP_NOFAIL
)) {
1741 /* The OOM killer will not help higher order allocs */
1742 if (order
> PAGE_ALLOC_COSTLY_ORDER
)
1745 * GFP_THISNODE contains __GFP_NORETRY and we never hit this.
1746 * Sanity check for bare calls of __GFP_THISNODE, not real OOM.
1747 * The caller should handle page allocation failure by itself if
1748 * it specifies __GFP_THISNODE.
1749 * Note: Hugepage uses it but will hit PAGE_ALLOC_COSTLY_ORDER.
1751 if (gfp_mask
& __GFP_THISNODE
)
1754 /* Exhausted what can be done so it's blamo time */
1755 out_of_memory(zonelist
, gfp_mask
, order
, nodemask
);
1758 clear_zonelist_oom(zonelist
, gfp_mask
);
1762 #ifdef CONFIG_COMPACTION
1763 /* Try memory compaction for high-order allocations before reclaim */
1764 static struct page
*
1765 __alloc_pages_direct_compact(gfp_t gfp_mask
, unsigned int order
,
1766 struct zonelist
*zonelist
, enum zone_type high_zoneidx
,
1767 nodemask_t
*nodemask
, int alloc_flags
, struct zone
*preferred_zone
,
1768 int migratetype
, unsigned long *did_some_progress
)
1775 *did_some_progress
= try_to_compact_pages(zonelist
, order
, gfp_mask
,
1777 if (*did_some_progress
!= COMPACT_SKIPPED
) {
1779 /* Page migration frees to the PCP lists but we want merging */
1780 drain_pages(get_cpu());
1783 page
= get_page_from_freelist(gfp_mask
, nodemask
,
1784 order
, zonelist
, high_zoneidx
,
1785 alloc_flags
, preferred_zone
,
1788 count_vm_event(COMPACTSUCCESS
);
1793 * It's bad if compaction run occurs and fails.
1794 * The most likely reason is that pages exist,
1795 * but not enough to satisfy watermarks.
1797 count_vm_event(COMPACTFAIL
);
1805 static inline struct page
*
1806 __alloc_pages_direct_compact(gfp_t gfp_mask
, unsigned int order
,
1807 struct zonelist
*zonelist
, enum zone_type high_zoneidx
,
1808 nodemask_t
*nodemask
, int alloc_flags
, struct zone
*preferred_zone
,
1809 int migratetype
, unsigned long *did_some_progress
)
1813 #endif /* CONFIG_COMPACTION */
1815 /* The really slow allocator path where we enter direct reclaim */
1816 static inline struct page
*
1817 __alloc_pages_direct_reclaim(gfp_t gfp_mask
, unsigned int order
,
1818 struct zonelist
*zonelist
, enum zone_type high_zoneidx
,
1819 nodemask_t
*nodemask
, int alloc_flags
, struct zone
*preferred_zone
,
1820 int migratetype
, unsigned long *did_some_progress
)
1822 struct page
*page
= NULL
;
1823 struct reclaim_state reclaim_state
;
1824 struct task_struct
*p
= current
;
1828 /* We now go into synchronous reclaim */
1829 cpuset_memory_pressure_bump();
1830 p
->flags
|= PF_MEMALLOC
;
1831 lockdep_set_current_reclaim_state(gfp_mask
);
1832 reclaim_state
.reclaimed_slab
= 0;
1833 p
->reclaim_state
= &reclaim_state
;
1835 *did_some_progress
= try_to_free_pages(zonelist
, order
, gfp_mask
, nodemask
);
1837 p
->reclaim_state
= NULL
;
1838 lockdep_clear_current_reclaim_state();
1839 p
->flags
&= ~PF_MEMALLOC
;
1846 if (likely(*did_some_progress
))
1847 page
= get_page_from_freelist(gfp_mask
, nodemask
, order
,
1848 zonelist
, high_zoneidx
,
1849 alloc_flags
, preferred_zone
,
1855 * This is called in the allocator slow-path if the allocation request is of
1856 * sufficient urgency to ignore watermarks and take other desperate measures
1858 static inline struct page
*
1859 __alloc_pages_high_priority(gfp_t gfp_mask
, unsigned int order
,
1860 struct zonelist
*zonelist
, enum zone_type high_zoneidx
,
1861 nodemask_t
*nodemask
, struct zone
*preferred_zone
,
1867 page
= get_page_from_freelist(gfp_mask
, nodemask
, order
,
1868 zonelist
, high_zoneidx
, ALLOC_NO_WATERMARKS
,
1869 preferred_zone
, migratetype
);
1871 if (!page
&& gfp_mask
& __GFP_NOFAIL
)
1872 congestion_wait(BLK_RW_ASYNC
, HZ
/50);
1873 } while (!page
&& (gfp_mask
& __GFP_NOFAIL
));
1879 void wake_all_kswapd(unsigned int order
, struct zonelist
*zonelist
,
1880 enum zone_type high_zoneidx
)
1885 for_each_zone_zonelist(zone
, z
, zonelist
, high_zoneidx
)
1886 wakeup_kswapd(zone
, order
);
1890 gfp_to_alloc_flags(gfp_t gfp_mask
)
1892 struct task_struct
*p
= current
;
1893 int alloc_flags
= ALLOC_WMARK_MIN
| ALLOC_CPUSET
;
1894 const gfp_t wait
= gfp_mask
& __GFP_WAIT
;
1896 /* __GFP_HIGH is assumed to be the same as ALLOC_HIGH to save a branch. */
1897 BUILD_BUG_ON(__GFP_HIGH
!= ALLOC_HIGH
);
1900 * The caller may dip into page reserves a bit more if the caller
1901 * cannot run direct reclaim, or if the caller has realtime scheduling
1902 * policy or is asking for __GFP_HIGH memory. GFP_ATOMIC requests will
1903 * set both ALLOC_HARDER (!wait) and ALLOC_HIGH (__GFP_HIGH).
1905 alloc_flags
|= (gfp_mask
& __GFP_HIGH
);
1908 alloc_flags
|= ALLOC_HARDER
;
1910 * Ignore cpuset if GFP_ATOMIC (!wait) rather than fail alloc.
1911 * See also cpuset_zone_allowed() comment in kernel/cpuset.c.
1913 alloc_flags
&= ~ALLOC_CPUSET
;
1914 } else if (unlikely(rt_task(p
)) && !in_interrupt())
1915 alloc_flags
|= ALLOC_HARDER
;
1917 if (likely(!(gfp_mask
& __GFP_NOMEMALLOC
))) {
1918 if (!in_interrupt() &&
1919 ((p
->flags
& PF_MEMALLOC
) ||
1920 unlikely(test_thread_flag(TIF_MEMDIE
))))
1921 alloc_flags
|= ALLOC_NO_WATERMARKS
;
1927 static inline struct page
*
1928 __alloc_pages_slowpath(gfp_t gfp_mask
, unsigned int order
,
1929 struct zonelist
*zonelist
, enum zone_type high_zoneidx
,
1930 nodemask_t
*nodemask
, struct zone
*preferred_zone
,
1933 const gfp_t wait
= gfp_mask
& __GFP_WAIT
;
1934 struct page
*page
= NULL
;
1936 unsigned long pages_reclaimed
= 0;
1937 unsigned long did_some_progress
;
1938 struct task_struct
*p
= current
;
1941 * In the slowpath, we sanity check order to avoid ever trying to
1942 * reclaim >= MAX_ORDER areas which will never succeed. Callers may
1943 * be using allocators in order of preference for an area that is
1946 if (order
>= MAX_ORDER
) {
1947 WARN_ON_ONCE(!(gfp_mask
& __GFP_NOWARN
));
1952 * GFP_THISNODE (meaning __GFP_THISNODE, __GFP_NORETRY and
1953 * __GFP_NOWARN set) should not cause reclaim since the subsystem
1954 * (f.e. slab) using GFP_THISNODE may choose to trigger reclaim
1955 * using a larger set of nodes after it has established that the
1956 * allowed per node queues are empty and that nodes are
1959 if (NUMA_BUILD
&& (gfp_mask
& GFP_THISNODE
) == GFP_THISNODE
)
1963 wake_all_kswapd(order
, zonelist
, high_zoneidx
);
1966 * OK, we're below the kswapd watermark and have kicked background
1967 * reclaim. Now things get more complex, so set up alloc_flags according
1968 * to how we want to proceed.
1970 alloc_flags
= gfp_to_alloc_flags(gfp_mask
);
1972 /* This is the last chance, in general, before the goto nopage. */
1973 page
= get_page_from_freelist(gfp_mask
, nodemask
, order
, zonelist
,
1974 high_zoneidx
, alloc_flags
& ~ALLOC_NO_WATERMARKS
,
1975 preferred_zone
, migratetype
);
1980 /* Allocate without watermarks if the context allows */
1981 if (alloc_flags
& ALLOC_NO_WATERMARKS
) {
1982 page
= __alloc_pages_high_priority(gfp_mask
, order
,
1983 zonelist
, high_zoneidx
, nodemask
,
1984 preferred_zone
, migratetype
);
1989 /* Atomic allocations - we can't balance anything */
1993 /* Avoid recursion of direct reclaim */
1994 if (p
->flags
& PF_MEMALLOC
)
1997 /* Avoid allocations with no watermarks from looping endlessly */
1998 if (test_thread_flag(TIF_MEMDIE
) && !(gfp_mask
& __GFP_NOFAIL
))
2001 /* Try direct compaction */
2002 page
= __alloc_pages_direct_compact(gfp_mask
, order
,
2003 zonelist
, high_zoneidx
,
2005 alloc_flags
, preferred_zone
,
2006 migratetype
, &did_some_progress
);
2010 /* Try direct reclaim and then allocating */
2011 page
= __alloc_pages_direct_reclaim(gfp_mask
, order
,
2012 zonelist
, high_zoneidx
,
2014 alloc_flags
, preferred_zone
,
2015 migratetype
, &did_some_progress
);
2020 * If we failed to make any progress reclaiming, then we are
2021 * running out of options and have to consider going OOM
2023 if (!did_some_progress
) {
2024 if ((gfp_mask
& __GFP_FS
) && !(gfp_mask
& __GFP_NORETRY
)) {
2025 if (oom_killer_disabled
)
2027 page
= __alloc_pages_may_oom(gfp_mask
, order
,
2028 zonelist
, high_zoneidx
,
2029 nodemask
, preferred_zone
,
2035 * The OOM killer does not trigger for high-order
2036 * ~__GFP_NOFAIL allocations so if no progress is being
2037 * made, there are no other options and retrying is
2040 if (order
> PAGE_ALLOC_COSTLY_ORDER
&&
2041 !(gfp_mask
& __GFP_NOFAIL
))
2048 /* Check if we should retry the allocation */
2049 pages_reclaimed
+= did_some_progress
;
2050 if (should_alloc_retry(gfp_mask
, order
, pages_reclaimed
)) {
2051 /* Wait for some write requests to complete then retry */
2052 congestion_wait(BLK_RW_ASYNC
, HZ
/50);
2057 if (!(gfp_mask
& __GFP_NOWARN
) && printk_ratelimit()) {
2058 printk(KERN_WARNING
"%s: page allocation failure."
2059 " order:%d, mode:0x%x\n",
2060 p
->comm
, order
, gfp_mask
);
2066 if (kmemcheck_enabled
)
2067 kmemcheck_pagealloc_alloc(page
, order
, gfp_mask
);
2073 * This is the 'heart' of the zoned buddy allocator.
2076 __alloc_pages_nodemask(gfp_t gfp_mask
, unsigned int order
,
2077 struct zonelist
*zonelist
, nodemask_t
*nodemask
)
2079 enum zone_type high_zoneidx
= gfp_zone(gfp_mask
);
2080 struct zone
*preferred_zone
;
2082 int migratetype
= allocflags_to_migratetype(gfp_mask
);
2084 gfp_mask
&= gfp_allowed_mask
;
2086 lockdep_trace_alloc(gfp_mask
);
2088 might_sleep_if(gfp_mask
& __GFP_WAIT
);
2090 if (should_fail_alloc_page(gfp_mask
, order
))
2094 * Check the zones suitable for the gfp_mask contain at least one
2095 * valid zone. It's possible to have an empty zonelist as a result
2096 * of GFP_THISNODE and a memoryless node
2098 if (unlikely(!zonelist
->_zonerefs
->zone
))
2102 /* The preferred zone is used for statistics later */
2103 first_zones_zonelist(zonelist
, high_zoneidx
, nodemask
, &preferred_zone
);
2104 if (!preferred_zone
) {
2109 /* First allocation attempt */
2110 page
= get_page_from_freelist(gfp_mask
|__GFP_HARDWALL
, nodemask
, order
,
2111 zonelist
, high_zoneidx
, ALLOC_WMARK_LOW
|ALLOC_CPUSET
,
2112 preferred_zone
, migratetype
);
2113 if (unlikely(!page
))
2114 page
= __alloc_pages_slowpath(gfp_mask
, order
,
2115 zonelist
, high_zoneidx
, nodemask
,
2116 preferred_zone
, migratetype
);
2119 trace_mm_page_alloc(page
, order
, gfp_mask
, migratetype
);
2122 EXPORT_SYMBOL(__alloc_pages_nodemask
);
2125 * Common helper functions.
2127 unsigned long __get_free_pages(gfp_t gfp_mask
, unsigned int order
)
2132 * __get_free_pages() returns a 32-bit address, which cannot represent
2135 VM_BUG_ON((gfp_mask
& __GFP_HIGHMEM
) != 0);
2137 page
= alloc_pages(gfp_mask
, order
);
2140 return (unsigned long) page_address(page
);
2142 EXPORT_SYMBOL(__get_free_pages
);
2144 unsigned long get_zeroed_page(gfp_t gfp_mask
)
2146 return __get_free_pages(gfp_mask
| __GFP_ZERO
, 0);
2148 EXPORT_SYMBOL(get_zeroed_page
);
2150 void __pagevec_free(struct pagevec
*pvec
)
2152 int i
= pagevec_count(pvec
);
2155 trace_mm_pagevec_free(pvec
->pages
[i
], pvec
->cold
);
2156 free_hot_cold_page(pvec
->pages
[i
], pvec
->cold
);
2160 void __free_pages(struct page
*page
, unsigned int order
)
2162 if (put_page_testzero(page
)) {
2164 free_hot_cold_page(page
, 0);
2166 __free_pages_ok(page
, order
);
2170 EXPORT_SYMBOL(__free_pages
);
2172 void free_pages(unsigned long addr
, unsigned int order
)
2175 VM_BUG_ON(!virt_addr_valid((void *)addr
));
2176 __free_pages(virt_to_page((void *)addr
), order
);
2180 EXPORT_SYMBOL(free_pages
);
2183 * alloc_pages_exact - allocate an exact number physically-contiguous pages.
2184 * @size: the number of bytes to allocate
2185 * @gfp_mask: GFP flags for the allocation
2187 * This function is similar to alloc_pages(), except that it allocates the
2188 * minimum number of pages to satisfy the request. alloc_pages() can only
2189 * allocate memory in power-of-two pages.
2191 * This function is also limited by MAX_ORDER.
2193 * Memory allocated by this function must be released by free_pages_exact().
2195 void *alloc_pages_exact(size_t size
, gfp_t gfp_mask
)
2197 unsigned int order
= get_order(size
);
2200 addr
= __get_free_pages(gfp_mask
, order
);
2202 unsigned long alloc_end
= addr
+ (PAGE_SIZE
<< order
);
2203 unsigned long used
= addr
+ PAGE_ALIGN(size
);
2205 split_page(virt_to_page((void *)addr
), order
);
2206 while (used
< alloc_end
) {
2212 return (void *)addr
;
2214 EXPORT_SYMBOL(alloc_pages_exact
);
2217 * free_pages_exact - release memory allocated via alloc_pages_exact()
2218 * @virt: the value returned by alloc_pages_exact.
2219 * @size: size of allocation, same value as passed to alloc_pages_exact().
2221 * Release the memory allocated by a previous call to alloc_pages_exact.
2223 void free_pages_exact(void *virt
, size_t size
)
2225 unsigned long addr
= (unsigned long)virt
;
2226 unsigned long end
= addr
+ PAGE_ALIGN(size
);
2228 while (addr
< end
) {
2233 EXPORT_SYMBOL(free_pages_exact
);
2235 static unsigned int nr_free_zone_pages(int offset
)
2240 /* Just pick one node, since fallback list is circular */
2241 unsigned int sum
= 0;
2243 struct zonelist
*zonelist
= node_zonelist(numa_node_id(), GFP_KERNEL
);
2245 for_each_zone_zonelist(zone
, z
, zonelist
, offset
) {
2246 unsigned long size
= zone
->present_pages
;
2247 unsigned long high
= high_wmark_pages(zone
);
2256 * Amount of free RAM allocatable within ZONE_DMA and ZONE_NORMAL
2258 unsigned int nr_free_buffer_pages(void)
2260 return nr_free_zone_pages(gfp_zone(GFP_USER
));
2262 EXPORT_SYMBOL_GPL(nr_free_buffer_pages
);
2265 * Amount of free RAM allocatable within all zones
2267 unsigned int nr_free_pagecache_pages(void)
2269 return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE
));
2272 static inline void show_node(struct zone
*zone
)
2275 printk("Node %d ", zone_to_nid(zone
));
2278 void si_meminfo(struct sysinfo
*val
)
2280 val
->totalram
= totalram_pages
;
2282 val
->freeram
= global_page_state(NR_FREE_PAGES
);
2283 val
->bufferram
= nr_blockdev_pages();
2284 val
->totalhigh
= totalhigh_pages
;
2285 val
->freehigh
= nr_free_highpages();
2286 val
->mem_unit
= PAGE_SIZE
;
2289 EXPORT_SYMBOL(si_meminfo
);
2292 void si_meminfo_node(struct sysinfo
*val
, int nid
)
2294 pg_data_t
*pgdat
= NODE_DATA(nid
);
2296 val
->totalram
= pgdat
->node_present_pages
;
2297 val
->freeram
= node_page_state(nid
, NR_FREE_PAGES
);
2298 #ifdef CONFIG_HIGHMEM
2299 val
->totalhigh
= pgdat
->node_zones
[ZONE_HIGHMEM
].present_pages
;
2300 val
->freehigh
= zone_page_state(&pgdat
->node_zones
[ZONE_HIGHMEM
],
2306 val
->mem_unit
= PAGE_SIZE
;
2310 #define K(x) ((x) << (PAGE_SHIFT-10))
2313 * Show free area list (used inside shift_scroll-lock stuff)
2314 * We also calculate the percentage fragmentation. We do this by counting the
2315 * memory on each free list with the exception of the first item on the list.
2317 void show_free_areas(void)
2322 for_each_populated_zone(zone
) {
2324 printk("%s per-cpu:\n", zone
->name
);
2326 for_each_online_cpu(cpu
) {
2327 struct per_cpu_pageset
*pageset
;
2329 pageset
= per_cpu_ptr(zone
->pageset
, cpu
);
2331 printk("CPU %4d: hi:%5d, btch:%4d usd:%4d\n",
2332 cpu
, pageset
->pcp
.high
,
2333 pageset
->pcp
.batch
, pageset
->pcp
.count
);
2337 printk("active_anon:%lu inactive_anon:%lu isolated_anon:%lu\n"
2338 " active_file:%lu inactive_file:%lu isolated_file:%lu\n"
2340 " dirty:%lu writeback:%lu unstable:%lu\n"
2341 " free:%lu slab_reclaimable:%lu slab_unreclaimable:%lu\n"
2342 " mapped:%lu shmem:%lu pagetables:%lu bounce:%lu\n",
2343 global_page_state(NR_ACTIVE_ANON
),
2344 global_page_state(NR_INACTIVE_ANON
),
2345 global_page_state(NR_ISOLATED_ANON
),
2346 global_page_state(NR_ACTIVE_FILE
),
2347 global_page_state(NR_INACTIVE_FILE
),
2348 global_page_state(NR_ISOLATED_FILE
),
2349 global_page_state(NR_UNEVICTABLE
),
2350 global_page_state(NR_FILE_DIRTY
),
2351 global_page_state(NR_WRITEBACK
),
2352 global_page_state(NR_UNSTABLE_NFS
),
2353 global_page_state(NR_FREE_PAGES
),
2354 global_page_state(NR_SLAB_RECLAIMABLE
),
2355 global_page_state(NR_SLAB_UNRECLAIMABLE
),
2356 global_page_state(NR_FILE_MAPPED
),
2357 global_page_state(NR_SHMEM
),
2358 global_page_state(NR_PAGETABLE
),
2359 global_page_state(NR_BOUNCE
));
2361 for_each_populated_zone(zone
) {
2370 " active_anon:%lukB"
2371 " inactive_anon:%lukB"
2372 " active_file:%lukB"
2373 " inactive_file:%lukB"
2374 " unevictable:%lukB"
2375 " isolated(anon):%lukB"
2376 " isolated(file):%lukB"
2383 " slab_reclaimable:%lukB"
2384 " slab_unreclaimable:%lukB"
2385 " kernel_stack:%lukB"
2389 " writeback_tmp:%lukB"
2390 " pages_scanned:%lu"
2391 " all_unreclaimable? %s"
2394 K(zone_page_state(zone
, NR_FREE_PAGES
)),
2395 K(min_wmark_pages(zone
)),
2396 K(low_wmark_pages(zone
)),
2397 K(high_wmark_pages(zone
)),
2398 K(zone_page_state(zone
, NR_ACTIVE_ANON
)),
2399 K(zone_page_state(zone
, NR_INACTIVE_ANON
)),
2400 K(zone_page_state(zone
, NR_ACTIVE_FILE
)),
2401 K(zone_page_state(zone
, NR_INACTIVE_FILE
)),
2402 K(zone_page_state(zone
, NR_UNEVICTABLE
)),
2403 K(zone_page_state(zone
, NR_ISOLATED_ANON
)),
2404 K(zone_page_state(zone
, NR_ISOLATED_FILE
)),
2405 K(zone
->present_pages
),
2406 K(zone_page_state(zone
, NR_MLOCK
)),
2407 K(zone_page_state(zone
, NR_FILE_DIRTY
)),
2408 K(zone_page_state(zone
, NR_WRITEBACK
)),
2409 K(zone_page_state(zone
, NR_FILE_MAPPED
)),
2410 K(zone_page_state(zone
, NR_SHMEM
)),
2411 K(zone_page_state(zone
, NR_SLAB_RECLAIMABLE
)),
2412 K(zone_page_state(zone
, NR_SLAB_UNRECLAIMABLE
)),
2413 zone_page_state(zone
, NR_KERNEL_STACK
) *
2415 K(zone_page_state(zone
, NR_PAGETABLE
)),
2416 K(zone_page_state(zone
, NR_UNSTABLE_NFS
)),
2417 K(zone_page_state(zone
, NR_BOUNCE
)),
2418 K(zone_page_state(zone
, NR_WRITEBACK_TEMP
)),
2419 zone
->pages_scanned
,
2420 (zone
->all_unreclaimable
? "yes" : "no")
2422 printk("lowmem_reserve[]:");
2423 for (i
= 0; i
< MAX_NR_ZONES
; i
++)
2424 printk(" %lu", zone
->lowmem_reserve
[i
]);
2428 for_each_populated_zone(zone
) {
2429 unsigned long nr
[MAX_ORDER
], flags
, order
, total
= 0;
2432 printk("%s: ", zone
->name
);
2434 spin_lock_irqsave(&zone
->lock
, flags
);
2435 for (order
= 0; order
< MAX_ORDER
; order
++) {
2436 nr
[order
] = zone
->free_area
[order
].nr_free
;
2437 total
+= nr
[order
] << order
;
2439 spin_unlock_irqrestore(&zone
->lock
, flags
);
2440 for (order
= 0; order
< MAX_ORDER
; order
++)
2441 printk("%lu*%lukB ", nr
[order
], K(1UL) << order
);
2442 printk("= %lukB\n", K(total
));
2445 printk("%ld total pagecache pages\n", global_page_state(NR_FILE_PAGES
));
2447 show_swap_cache_info();
2450 static void zoneref_set_zone(struct zone
*zone
, struct zoneref
*zoneref
)
2452 zoneref
->zone
= zone
;
2453 zoneref
->zone_idx
= zone_idx(zone
);
2457 * Builds allocation fallback zone lists.
2459 * Add all populated zones of a node to the zonelist.
2461 static int build_zonelists_node(pg_data_t
*pgdat
, struct zonelist
*zonelist
,
2462 int nr_zones
, enum zone_type zone_type
)
2466 BUG_ON(zone_type
>= MAX_NR_ZONES
);
2471 zone
= pgdat
->node_zones
+ zone_type
;
2472 if (populated_zone(zone
)) {
2473 zoneref_set_zone(zone
,
2474 &zonelist
->_zonerefs
[nr_zones
++]);
2475 check_highest_zone(zone_type
);
2478 } while (zone_type
);
2485 * 0 = automatic detection of better ordering.
2486 * 1 = order by ([node] distance, -zonetype)
2487 * 2 = order by (-zonetype, [node] distance)
2489 * If not NUMA, ZONELIST_ORDER_ZONE and ZONELIST_ORDER_NODE will create
2490 * the same zonelist. So only NUMA can configure this param.
2492 #define ZONELIST_ORDER_DEFAULT 0
2493 #define ZONELIST_ORDER_NODE 1
2494 #define ZONELIST_ORDER_ZONE 2
2496 /* zonelist order in the kernel.
2497 * set_zonelist_order() will set this to NODE or ZONE.
2499 static int current_zonelist_order
= ZONELIST_ORDER_DEFAULT
;
2500 static char zonelist_order_name
[3][8] = {"Default", "Node", "Zone"};
2504 /* The value user specified ....changed by config */
2505 static int user_zonelist_order
= ZONELIST_ORDER_DEFAULT
;
2506 /* string for sysctl */
2507 #define NUMA_ZONELIST_ORDER_LEN 16
2508 char numa_zonelist_order
[16] = "default";
2511 * interface for configure zonelist ordering.
2512 * command line option "numa_zonelist_order"
2513 * = "[dD]efault - default, automatic configuration.
2514 * = "[nN]ode - order by node locality, then by zone within node
2515 * = "[zZ]one - order by zone, then by locality within zone
2518 static int __parse_numa_zonelist_order(char *s
)
2520 if (*s
== 'd' || *s
== 'D') {
2521 user_zonelist_order
= ZONELIST_ORDER_DEFAULT
;
2522 } else if (*s
== 'n' || *s
== 'N') {
2523 user_zonelist_order
= ZONELIST_ORDER_NODE
;
2524 } else if (*s
== 'z' || *s
== 'Z') {
2525 user_zonelist_order
= ZONELIST_ORDER_ZONE
;
2528 "Ignoring invalid numa_zonelist_order value: "
2535 static __init
int setup_numa_zonelist_order(char *s
)
2538 return __parse_numa_zonelist_order(s
);
2541 early_param("numa_zonelist_order", setup_numa_zonelist_order
);
2544 * sysctl handler for numa_zonelist_order
2546 int numa_zonelist_order_handler(ctl_table
*table
, int write
,
2547 void __user
*buffer
, size_t *length
,
2550 char saved_string
[NUMA_ZONELIST_ORDER_LEN
];
2552 static DEFINE_MUTEX(zl_order_mutex
);
2554 mutex_lock(&zl_order_mutex
);
2556 strcpy(saved_string
, (char*)table
->data
);
2557 ret
= proc_dostring(table
, write
, buffer
, length
, ppos
);
2561 int oldval
= user_zonelist_order
;
2562 if (__parse_numa_zonelist_order((char*)table
->data
)) {
2564 * bogus value. restore saved string
2566 strncpy((char*)table
->data
, saved_string
,
2567 NUMA_ZONELIST_ORDER_LEN
);
2568 user_zonelist_order
= oldval
;
2569 } else if (oldval
!= user_zonelist_order
)
2570 build_all_zonelists();
2573 mutex_unlock(&zl_order_mutex
);
2578 #define MAX_NODE_LOAD (nr_online_nodes)
2579 static int node_load
[MAX_NUMNODES
];
2582 * find_next_best_node - find the next node that should appear in a given node's fallback list
2583 * @node: node whose fallback list we're appending
2584 * @used_node_mask: nodemask_t of already used nodes
2586 * We use a number of factors to determine which is the next node that should
2587 * appear on a given node's fallback list. The node should not have appeared
2588 * already in @node's fallback list, and it should be the next closest node
2589 * according to the distance array (which contains arbitrary distance values
2590 * from each node to each node in the system), and should also prefer nodes
2591 * with no CPUs, since presumably they'll have very little allocation pressure
2592 * on them otherwise.
2593 * It returns -1 if no node is found.
2595 static int find_next_best_node(int node
, nodemask_t
*used_node_mask
)
2598 int min_val
= INT_MAX
;
2600 const struct cpumask
*tmp
= cpumask_of_node(0);
2602 /* Use the local node if we haven't already */
2603 if (!node_isset(node
, *used_node_mask
)) {
2604 node_set(node
, *used_node_mask
);
2608 for_each_node_state(n
, N_HIGH_MEMORY
) {
2610 /* Don't want a node to appear more than once */
2611 if (node_isset(n
, *used_node_mask
))
2614 /* Use the distance array to find the distance */
2615 val
= node_distance(node
, n
);
2617 /* Penalize nodes under us ("prefer the next node") */
2620 /* Give preference to headless and unused nodes */
2621 tmp
= cpumask_of_node(n
);
2622 if (!cpumask_empty(tmp
))
2623 val
+= PENALTY_FOR_NODE_WITH_CPUS
;
2625 /* Slight preference for less loaded node */
2626 val
*= (MAX_NODE_LOAD
*MAX_NUMNODES
);
2627 val
+= node_load
[n
];
2629 if (val
< min_val
) {
2636 node_set(best_node
, *used_node_mask
);
2643 * Build zonelists ordered by node and zones within node.
2644 * This results in maximum locality--normal zone overflows into local
2645 * DMA zone, if any--but risks exhausting DMA zone.
2647 static void build_zonelists_in_node_order(pg_data_t
*pgdat
, int node
)
2650 struct zonelist
*zonelist
;
2652 zonelist
= &pgdat
->node_zonelists
[0];
2653 for (j
= 0; zonelist
->_zonerefs
[j
].zone
!= NULL
; j
++)
2655 j
= build_zonelists_node(NODE_DATA(node
), zonelist
, j
,
2657 zonelist
->_zonerefs
[j
].zone
= NULL
;
2658 zonelist
->_zonerefs
[j
].zone_idx
= 0;
2662 * Build gfp_thisnode zonelists
2664 static void build_thisnode_zonelists(pg_data_t
*pgdat
)
2667 struct zonelist
*zonelist
;
2669 zonelist
= &pgdat
->node_zonelists
[1];
2670 j
= build_zonelists_node(pgdat
, zonelist
, 0, MAX_NR_ZONES
- 1);
2671 zonelist
->_zonerefs
[j
].zone
= NULL
;
2672 zonelist
->_zonerefs
[j
].zone_idx
= 0;
2676 * Build zonelists ordered by zone and nodes within zones.
2677 * This results in conserving DMA zone[s] until all Normal memory is
2678 * exhausted, but results in overflowing to remote node while memory
2679 * may still exist in local DMA zone.
2681 static int node_order
[MAX_NUMNODES
];
2683 static void build_zonelists_in_zone_order(pg_data_t
*pgdat
, int nr_nodes
)
2686 int zone_type
; /* needs to be signed */
2688 struct zonelist
*zonelist
;
2690 zonelist
= &pgdat
->node_zonelists
[0];
2692 for (zone_type
= MAX_NR_ZONES
- 1; zone_type
>= 0; zone_type
--) {
2693 for (j
= 0; j
< nr_nodes
; j
++) {
2694 node
= node_order
[j
];
2695 z
= &NODE_DATA(node
)->node_zones
[zone_type
];
2696 if (populated_zone(z
)) {
2698 &zonelist
->_zonerefs
[pos
++]);
2699 check_highest_zone(zone_type
);
2703 zonelist
->_zonerefs
[pos
].zone
= NULL
;
2704 zonelist
->_zonerefs
[pos
].zone_idx
= 0;
2707 static int default_zonelist_order(void)
2710 unsigned long low_kmem_size
,total_size
;
2714 * ZONE_DMA and ZONE_DMA32 can be very small area in the system.
2715 * If they are really small and used heavily, the system can fall
2716 * into OOM very easily.
2717 * This function detect ZONE_DMA/DMA32 size and configures zone order.
2719 /* Is there ZONE_NORMAL ? (ex. ppc has only DMA zone..) */
2722 for_each_online_node(nid
) {
2723 for (zone_type
= 0; zone_type
< MAX_NR_ZONES
; zone_type
++) {
2724 z
= &NODE_DATA(nid
)->node_zones
[zone_type
];
2725 if (populated_zone(z
)) {
2726 if (zone_type
< ZONE_NORMAL
)
2727 low_kmem_size
+= z
->present_pages
;
2728 total_size
+= z
->present_pages
;
2729 } else if (zone_type
== ZONE_NORMAL
) {
2731 * If any node has only lowmem, then node order
2732 * is preferred to allow kernel allocations
2733 * locally; otherwise, they can easily infringe
2734 * on other nodes when there is an abundance of
2735 * lowmem available to allocate from.
2737 return ZONELIST_ORDER_NODE
;
2741 if (!low_kmem_size
|| /* there are no DMA area. */
2742 low_kmem_size
> total_size
/2) /* DMA/DMA32 is big. */
2743 return ZONELIST_ORDER_NODE
;
2745 * look into each node's config.
2746 * If there is a node whose DMA/DMA32 memory is very big area on
2747 * local memory, NODE_ORDER may be suitable.
2749 average_size
= total_size
/
2750 (nodes_weight(node_states
[N_HIGH_MEMORY
]) + 1);
2751 for_each_online_node(nid
) {
2754 for (zone_type
= 0; zone_type
< MAX_NR_ZONES
; zone_type
++) {
2755 z
= &NODE_DATA(nid
)->node_zones
[zone_type
];
2756 if (populated_zone(z
)) {
2757 if (zone_type
< ZONE_NORMAL
)
2758 low_kmem_size
+= z
->present_pages
;
2759 total_size
+= z
->present_pages
;
2762 if (low_kmem_size
&&
2763 total_size
> average_size
&& /* ignore small node */
2764 low_kmem_size
> total_size
* 70/100)
2765 return ZONELIST_ORDER_NODE
;
2767 return ZONELIST_ORDER_ZONE
;
2770 static void set_zonelist_order(void)
2772 if (user_zonelist_order
== ZONELIST_ORDER_DEFAULT
)
2773 current_zonelist_order
= default_zonelist_order();
2775 current_zonelist_order
= user_zonelist_order
;
2778 static void build_zonelists(pg_data_t
*pgdat
)
2782 nodemask_t used_mask
;
2783 int local_node
, prev_node
;
2784 struct zonelist
*zonelist
;
2785 int order
= current_zonelist_order
;
2787 /* initialize zonelists */
2788 for (i
= 0; i
< MAX_ZONELISTS
; i
++) {
2789 zonelist
= pgdat
->node_zonelists
+ i
;
2790 zonelist
->_zonerefs
[0].zone
= NULL
;
2791 zonelist
->_zonerefs
[0].zone_idx
= 0;
2794 /* NUMA-aware ordering of nodes */
2795 local_node
= pgdat
->node_id
;
2796 load
= nr_online_nodes
;
2797 prev_node
= local_node
;
2798 nodes_clear(used_mask
);
2800 memset(node_order
, 0, sizeof(node_order
));
2803 while ((node
= find_next_best_node(local_node
, &used_mask
)) >= 0) {
2804 int distance
= node_distance(local_node
, node
);
2807 * If another node is sufficiently far away then it is better
2808 * to reclaim pages in a zone before going off node.
2810 if (distance
> RECLAIM_DISTANCE
)
2811 zone_reclaim_mode
= 1;
2814 * We don't want to pressure a particular node.
2815 * So adding penalty to the first node in same
2816 * distance group to make it round-robin.
2818 if (distance
!= node_distance(local_node
, prev_node
))
2819 node_load
[node
] = load
;
2823 if (order
== ZONELIST_ORDER_NODE
)
2824 build_zonelists_in_node_order(pgdat
, node
);
2826 node_order
[j
++] = node
; /* remember order */
2829 if (order
== ZONELIST_ORDER_ZONE
) {
2830 /* calculate node order -- i.e., DMA last! */
2831 build_zonelists_in_zone_order(pgdat
, j
);
2834 build_thisnode_zonelists(pgdat
);
2837 /* Construct the zonelist performance cache - see further mmzone.h */
2838 static void build_zonelist_cache(pg_data_t
*pgdat
)
2840 struct zonelist
*zonelist
;
2841 struct zonelist_cache
*zlc
;
2844 zonelist
= &pgdat
->node_zonelists
[0];
2845 zonelist
->zlcache_ptr
= zlc
= &zonelist
->zlcache
;
2846 bitmap_zero(zlc
->fullzones
, MAX_ZONES_PER_ZONELIST
);
2847 for (z
= zonelist
->_zonerefs
; z
->zone
; z
++)
2848 zlc
->z_to_n
[z
- zonelist
->_zonerefs
] = zonelist_node_idx(z
);
2852 #else /* CONFIG_NUMA */
2854 static void set_zonelist_order(void)
2856 current_zonelist_order
= ZONELIST_ORDER_ZONE
;
2859 static void build_zonelists(pg_data_t
*pgdat
)
2861 int node
, local_node
;
2863 struct zonelist
*zonelist
;
2865 local_node
= pgdat
->node_id
;
2867 zonelist
= &pgdat
->node_zonelists
[0];
2868 j
= build_zonelists_node(pgdat
, zonelist
, 0, MAX_NR_ZONES
- 1);
2871 * Now we build the zonelist so that it contains the zones
2872 * of all the other nodes.
2873 * We don't want to pressure a particular node, so when
2874 * building the zones for node N, we make sure that the
2875 * zones coming right after the local ones are those from
2876 * node N+1 (modulo N)
2878 for (node
= local_node
+ 1; node
< MAX_NUMNODES
; node
++) {
2879 if (!node_online(node
))
2881 j
= build_zonelists_node(NODE_DATA(node
), zonelist
, j
,
2884 for (node
= 0; node
< local_node
; node
++) {
2885 if (!node_online(node
))
2887 j
= build_zonelists_node(NODE_DATA(node
), zonelist
, j
,
2891 zonelist
->_zonerefs
[j
].zone
= NULL
;
2892 zonelist
->_zonerefs
[j
].zone_idx
= 0;
2895 /* non-NUMA variant of zonelist performance cache - just NULL zlcache_ptr */
2896 static void build_zonelist_cache(pg_data_t
*pgdat
)
2898 pgdat
->node_zonelists
[0].zlcache_ptr
= NULL
;
2901 #endif /* CONFIG_NUMA */
2904 * Boot pageset table. One per cpu which is going to be used for all
2905 * zones and all nodes. The parameters will be set in such a way
2906 * that an item put on a list will immediately be handed over to
2907 * the buddy list. This is safe since pageset manipulation is done
2908 * with interrupts disabled.
2910 * The boot_pagesets must be kept even after bootup is complete for
2911 * unused processors and/or zones. They do play a role for bootstrapping
2912 * hotplugged processors.
2914 * zoneinfo_show() and maybe other functions do
2915 * not check if the processor is online before following the pageset pointer.
2916 * Other parts of the kernel may not check if the zone is available.
2918 static void setup_pageset(struct per_cpu_pageset
*p
, unsigned long batch
);
2919 static DEFINE_PER_CPU(struct per_cpu_pageset
, boot_pageset
);
2921 /* return values int ....just for stop_machine() */
2922 static int __build_all_zonelists(void *dummy
)
2928 memset(node_load
, 0, sizeof(node_load
));
2930 for_each_online_node(nid
) {
2931 pg_data_t
*pgdat
= NODE_DATA(nid
);
2933 build_zonelists(pgdat
);
2934 build_zonelist_cache(pgdat
);
2938 * Initialize the boot_pagesets that are going to be used
2939 * for bootstrapping processors. The real pagesets for
2940 * each zone will be allocated later when the per cpu
2941 * allocator is available.
2943 * boot_pagesets are used also for bootstrapping offline
2944 * cpus if the system is already booted because the pagesets
2945 * are needed to initialize allocators on a specific cpu too.
2946 * F.e. the percpu allocator needs the page allocator which
2947 * needs the percpu allocator in order to allocate its pagesets
2948 * (a chicken-egg dilemma).
2950 for_each_possible_cpu(cpu
)
2951 setup_pageset(&per_cpu(boot_pageset
, cpu
), 0);
2956 void build_all_zonelists(void)
2958 set_zonelist_order();
2960 if (system_state
== SYSTEM_BOOTING
) {
2961 __build_all_zonelists(NULL
);
2962 mminit_verify_zonelist();
2963 cpuset_init_current_mems_allowed();
2965 /* we have to stop all cpus to guarantee there is no user
2967 stop_machine(__build_all_zonelists
, NULL
, NULL
);
2968 /* cpuset refresh routine should be here */
2970 vm_total_pages
= nr_free_pagecache_pages();
2972 * Disable grouping by mobility if the number of pages in the
2973 * system is too low to allow the mechanism to work. It would be
2974 * more accurate, but expensive to check per-zone. This check is
2975 * made on memory-hotadd so a system can start with mobility
2976 * disabled and enable it later
2978 if (vm_total_pages
< (pageblock_nr_pages
* MIGRATE_TYPES
))
2979 page_group_by_mobility_disabled
= 1;
2981 page_group_by_mobility_disabled
= 0;
2983 printk("Built %i zonelists in %s order, mobility grouping %s. "
2984 "Total pages: %ld\n",
2986 zonelist_order_name
[current_zonelist_order
],
2987 page_group_by_mobility_disabled
? "off" : "on",
2990 printk("Policy zone: %s\n", zone_names
[policy_zone
]);
2995 * Helper functions to size the waitqueue hash table.
2996 * Essentially these want to choose hash table sizes sufficiently
2997 * large so that collisions trying to wait on pages are rare.
2998 * But in fact, the number of active page waitqueues on typical
2999 * systems is ridiculously low, less than 200. So this is even
3000 * conservative, even though it seems large.
3002 * The constant PAGES_PER_WAITQUEUE specifies the ratio of pages to
3003 * waitqueues, i.e. the size of the waitq table given the number of pages.
3005 #define PAGES_PER_WAITQUEUE 256
3007 #ifndef CONFIG_MEMORY_HOTPLUG
3008 static inline unsigned long wait_table_hash_nr_entries(unsigned long pages
)
3010 unsigned long size
= 1;
3012 pages
/= PAGES_PER_WAITQUEUE
;
3014 while (size
< pages
)
3018 * Once we have dozens or even hundreds of threads sleeping
3019 * on IO we've got bigger problems than wait queue collision.
3020 * Limit the size of the wait table to a reasonable size.
3022 size
= min(size
, 4096UL);
3024 return max(size
, 4UL);
3028 * A zone's size might be changed by hot-add, so it is not possible to determine
3029 * a suitable size for its wait_table. So we use the maximum size now.
3031 * The max wait table size = 4096 x sizeof(wait_queue_head_t). ie:
3033 * i386 (preemption config) : 4096 x 16 = 64Kbyte.
3034 * ia64, x86-64 (no preemption): 4096 x 20 = 80Kbyte.
3035 * ia64, x86-64 (preemption) : 4096 x 24 = 96Kbyte.
3037 * The maximum entries are prepared when a zone's memory is (512K + 256) pages
3038 * or more by the traditional way. (See above). It equals:
3040 * i386, x86-64, powerpc(4K page size) : = ( 2G + 1M)byte.
3041 * ia64(16K page size) : = ( 8G + 4M)byte.
3042 * powerpc (64K page size) : = (32G +16M)byte.
3044 static inline unsigned long wait_table_hash_nr_entries(unsigned long pages
)
3051 * This is an integer logarithm so that shifts can be used later
3052 * to extract the more random high bits from the multiplicative
3053 * hash function before the remainder is taken.
3055 static inline unsigned long wait_table_bits(unsigned long size
)
3060 #define LONG_ALIGN(x) (((x)+(sizeof(long))-1)&~((sizeof(long))-1))
3063 * Mark a number of pageblocks as MIGRATE_RESERVE. The number
3064 * of blocks reserved is based on min_wmark_pages(zone). The memory within
3065 * the reserve will tend to store contiguous free pages. Setting min_free_kbytes
3066 * higher will lead to a bigger reserve which will get freed as contiguous
3067 * blocks as reclaim kicks in
3069 static void setup_zone_migrate_reserve(struct zone
*zone
)
3071 unsigned long start_pfn
, pfn
, end_pfn
;
3073 unsigned long block_migratetype
;
3076 /* Get the start pfn, end pfn and the number of blocks to reserve */
3077 start_pfn
= zone
->zone_start_pfn
;
3078 end_pfn
= start_pfn
+ zone
->spanned_pages
;
3079 reserve
= roundup(min_wmark_pages(zone
), pageblock_nr_pages
) >>
3083 * Reserve blocks are generally in place to help high-order atomic
3084 * allocations that are short-lived. A min_free_kbytes value that
3085 * would result in more than 2 reserve blocks for atomic allocations
3086 * is assumed to be in place to help anti-fragmentation for the
3087 * future allocation of hugepages at runtime.
3089 reserve
= min(2, reserve
);
3091 for (pfn
= start_pfn
; pfn
< end_pfn
; pfn
+= pageblock_nr_pages
) {
3092 if (!pfn_valid(pfn
))
3094 page
= pfn_to_page(pfn
);
3096 /* Watch out for overlapping nodes */
3097 if (page_to_nid(page
) != zone_to_nid(zone
))
3100 /* Blocks with reserved pages will never free, skip them. */
3101 if (PageReserved(page
))
3104 block_migratetype
= get_pageblock_migratetype(page
);
3106 /* If this block is reserved, account for it */
3107 if (reserve
> 0 && block_migratetype
== MIGRATE_RESERVE
) {
3112 /* Suitable for reserving if this block is movable */
3113 if (reserve
> 0 && block_migratetype
== MIGRATE_MOVABLE
) {
3114 set_pageblock_migratetype(page
, MIGRATE_RESERVE
);
3115 move_freepages_block(zone
, page
, MIGRATE_RESERVE
);
3121 * If the reserve is met and this is a previous reserved block,
3124 if (block_migratetype
== MIGRATE_RESERVE
) {
3125 set_pageblock_migratetype(page
, MIGRATE_MOVABLE
);
3126 move_freepages_block(zone
, page
, MIGRATE_MOVABLE
);
3132 * Initially all pages are reserved - free ones are freed
3133 * up by free_all_bootmem() once the early boot process is
3134 * done. Non-atomic initialization, single-pass.
3136 void __meminit
memmap_init_zone(unsigned long size
, int nid
, unsigned long zone
,
3137 unsigned long start_pfn
, enum memmap_context context
)
3140 unsigned long end_pfn
= start_pfn
+ size
;
3144 if (highest_memmap_pfn
< end_pfn
- 1)
3145 highest_memmap_pfn
= end_pfn
- 1;
3147 z
= &NODE_DATA(nid
)->node_zones
[zone
];
3148 for (pfn
= start_pfn
; pfn
< end_pfn
; pfn
++) {
3150 * There can be holes in boot-time mem_map[]s
3151 * handed to this function. They do not
3152 * exist on hotplugged memory.
3154 if (context
== MEMMAP_EARLY
) {
3155 if (!early_pfn_valid(pfn
))
3157 if (!early_pfn_in_nid(pfn
, nid
))
3160 page
= pfn_to_page(pfn
);
3161 set_page_links(page
, zone
, nid
, pfn
);
3162 mminit_verify_page_links(page
, zone
, nid
, pfn
);
3163 init_page_count(page
);
3164 reset_page_mapcount(page
);
3165 SetPageReserved(page
);
3167 * Mark the block movable so that blocks are reserved for
3168 * movable at startup. This will force kernel allocations
3169 * to reserve their blocks rather than leaking throughout
3170 * the address space during boot when many long-lived
3171 * kernel allocations are made. Later some blocks near
3172 * the start are marked MIGRATE_RESERVE by
3173 * setup_zone_migrate_reserve()
3175 * bitmap is created for zone's valid pfn range. but memmap
3176 * can be created for invalid pages (for alignment)
3177 * check here not to call set_pageblock_migratetype() against
3180 if ((z
->zone_start_pfn
<= pfn
)
3181 && (pfn
< z
->zone_start_pfn
+ z
->spanned_pages
)
3182 && !(pfn
& (pageblock_nr_pages
- 1)))
3183 set_pageblock_migratetype(page
, MIGRATE_MOVABLE
);
3185 INIT_LIST_HEAD(&page
->lru
);
3186 #ifdef WANT_PAGE_VIRTUAL
3187 /* The shift won't overflow because ZONE_NORMAL is below 4G. */
3188 if (!is_highmem_idx(zone
))
3189 set_page_address(page
, __va(pfn
<< PAGE_SHIFT
));
3194 static void __meminit
zone_init_free_lists(struct zone
*zone
)
3197 for_each_migratetype_order(order
, t
) {
3198 INIT_LIST_HEAD(&zone
->free_area
[order
].free_list
[t
]);
3199 zone
->free_area
[order
].nr_free
= 0;
3203 #ifndef __HAVE_ARCH_MEMMAP_INIT
3204 #define memmap_init(size, nid, zone, start_pfn) \
3205 memmap_init_zone((size), (nid), (zone), (start_pfn), MEMMAP_EARLY)
3208 static int zone_batchsize(struct zone
*zone
)
3214 * The per-cpu-pages pools are set to around 1000th of the
3215 * size of the zone. But no more than 1/2 of a meg.
3217 * OK, so we don't know how big the cache is. So guess.
3219 batch
= zone
->present_pages
/ 1024;
3220 if (batch
* PAGE_SIZE
> 512 * 1024)
3221 batch
= (512 * 1024) / PAGE_SIZE
;
3222 batch
/= 4; /* We effectively *= 4 below */
3227 * Clamp the batch to a 2^n - 1 value. Having a power
3228 * of 2 value was found to be more likely to have
3229 * suboptimal cache aliasing properties in some cases.
3231 * For example if 2 tasks are alternately allocating
3232 * batches of pages, one task can end up with a lot
3233 * of pages of one half of the possible page colors
3234 * and the other with pages of the other colors.
3236 batch
= rounddown_pow_of_two(batch
+ batch
/2) - 1;
3241 /* The deferral and batching of frees should be suppressed under NOMMU
3244 * The problem is that NOMMU needs to be able to allocate large chunks
3245 * of contiguous memory as there's no hardware page translation to
3246 * assemble apparent contiguous memory from discontiguous pages.
3248 * Queueing large contiguous runs of pages for batching, however,
3249 * causes the pages to actually be freed in smaller chunks. As there
3250 * can be a significant delay between the individual batches being
3251 * recycled, this leads to the once large chunks of space being
3252 * fragmented and becoming unavailable for high-order allocations.
3258 static void setup_pageset(struct per_cpu_pageset
*p
, unsigned long batch
)
3260 struct per_cpu_pages
*pcp
;
3263 memset(p
, 0, sizeof(*p
));
3267 pcp
->high
= 6 * batch
;
3268 pcp
->batch
= max(1UL, 1 * batch
);
3269 for (migratetype
= 0; migratetype
< MIGRATE_PCPTYPES
; migratetype
++)
3270 INIT_LIST_HEAD(&pcp
->lists
[migratetype
]);
3274 * setup_pagelist_highmark() sets the high water mark for hot per_cpu_pagelist
3275 * to the value high for the pageset p.
3278 static void setup_pagelist_highmark(struct per_cpu_pageset
*p
,
3281 struct per_cpu_pages
*pcp
;
3285 pcp
->batch
= max(1UL, high
/4);
3286 if ((high
/4) > (PAGE_SHIFT
* 8))
3287 pcp
->batch
= PAGE_SHIFT
* 8;
3291 * Allocate per cpu pagesets and initialize them.
3292 * Before this call only boot pagesets were available.
3293 * Boot pagesets will no longer be used by this processorr
3294 * after setup_per_cpu_pageset().
3296 void __init
setup_per_cpu_pageset(void)
3301 for_each_populated_zone(zone
) {
3302 zone
->pageset
= alloc_percpu(struct per_cpu_pageset
);
3304 for_each_possible_cpu(cpu
) {
3305 struct per_cpu_pageset
*pcp
= per_cpu_ptr(zone
->pageset
, cpu
);
3307 setup_pageset(pcp
, zone_batchsize(zone
));
3309 if (percpu_pagelist_fraction
)
3310 setup_pagelist_highmark(pcp
,
3311 (zone
->present_pages
/
3312 percpu_pagelist_fraction
));
3317 static noinline __init_refok
3318 int zone_wait_table_init(struct zone
*zone
, unsigned long zone_size_pages
)
3321 struct pglist_data
*pgdat
= zone
->zone_pgdat
;
3325 * The per-page waitqueue mechanism uses hashed waitqueues
3328 zone
->wait_table_hash_nr_entries
=
3329 wait_table_hash_nr_entries(zone_size_pages
);
3330 zone
->wait_table_bits
=
3331 wait_table_bits(zone
->wait_table_hash_nr_entries
);
3332 alloc_size
= zone
->wait_table_hash_nr_entries
3333 * sizeof(wait_queue_head_t
);
3335 if (!slab_is_available()) {
3336 zone
->wait_table
= (wait_queue_head_t
*)
3337 alloc_bootmem_node(pgdat
, alloc_size
);
3340 * This case means that a zone whose size was 0 gets new memory
3341 * via memory hot-add.
3342 * But it may be the case that a new node was hot-added. In
3343 * this case vmalloc() will not be able to use this new node's
3344 * memory - this wait_table must be initialized to use this new
3345 * node itself as well.
3346 * To use this new node's memory, further consideration will be
3349 zone
->wait_table
= vmalloc(alloc_size
);
3351 if (!zone
->wait_table
)
3354 for(i
= 0; i
< zone
->wait_table_hash_nr_entries
; ++i
)
3355 init_waitqueue_head(zone
->wait_table
+ i
);
3360 static int __zone_pcp_update(void *data
)
3362 struct zone
*zone
= data
;
3364 unsigned long batch
= zone_batchsize(zone
), flags
;
3366 for_each_possible_cpu(cpu
) {
3367 struct per_cpu_pageset
*pset
;
3368 struct per_cpu_pages
*pcp
;
3370 pset
= per_cpu_ptr(zone
->pageset
, cpu
);
3373 local_irq_save(flags
);
3374 free_pcppages_bulk(zone
, pcp
->count
, pcp
);
3375 setup_pageset(pset
, batch
);
3376 local_irq_restore(flags
);
3381 void zone_pcp_update(struct zone
*zone
)
3383 stop_machine(__zone_pcp_update
, zone
, NULL
);
3386 static __meminit
void zone_pcp_init(struct zone
*zone
)
3389 * per cpu subsystem is not up at this point. The following code
3390 * relies on the ability of the linker to provide the
3391 * offset of a (static) per cpu variable into the per cpu area.
3393 zone
->pageset
= &boot_pageset
;
3395 if (zone
->present_pages
)
3396 printk(KERN_DEBUG
" %s zone: %lu pages, LIFO batch:%u\n",
3397 zone
->name
, zone
->present_pages
,
3398 zone_batchsize(zone
));
3401 __meminit
int init_currently_empty_zone(struct zone
*zone
,
3402 unsigned long zone_start_pfn
,
3404 enum memmap_context context
)
3406 struct pglist_data
*pgdat
= zone
->zone_pgdat
;
3408 ret
= zone_wait_table_init(zone
, size
);
3411 pgdat
->nr_zones
= zone_idx(zone
) + 1;
3413 zone
->zone_start_pfn
= zone_start_pfn
;
3415 mminit_dprintk(MMINIT_TRACE
, "memmap_init",
3416 "Initialising map node %d zone %lu pfns %lu -> %lu\n",
3418 (unsigned long)zone_idx(zone
),
3419 zone_start_pfn
, (zone_start_pfn
+ size
));
3421 zone_init_free_lists(zone
);
3426 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
3428 * Basic iterator support. Return the first range of PFNs for a node
3429 * Note: nid == MAX_NUMNODES returns first region regardless of node
3431 static int __meminit
first_active_region_index_in_nid(int nid
)
3435 for (i
= 0; i
< nr_nodemap_entries
; i
++)
3436 if (nid
== MAX_NUMNODES
|| early_node_map
[i
].nid
== nid
)
3443 * Basic iterator support. Return the next active range of PFNs for a node
3444 * Note: nid == MAX_NUMNODES returns next region regardless of node
3446 static int __meminit
next_active_region_index_in_nid(int index
, int nid
)
3448 for (index
= index
+ 1; index
< nr_nodemap_entries
; index
++)
3449 if (nid
== MAX_NUMNODES
|| early_node_map
[index
].nid
== nid
)
3455 #ifndef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
3457 * Required by SPARSEMEM. Given a PFN, return what node the PFN is on.
3458 * Architectures may implement their own version but if add_active_range()
3459 * was used and there are no special requirements, this is a convenient
3462 int __meminit
__early_pfn_to_nid(unsigned long pfn
)
3466 for (i
= 0; i
< nr_nodemap_entries
; i
++) {
3467 unsigned long start_pfn
= early_node_map
[i
].start_pfn
;
3468 unsigned long end_pfn
= early_node_map
[i
].end_pfn
;
3470 if (start_pfn
<= pfn
&& pfn
< end_pfn
)
3471 return early_node_map
[i
].nid
;
3473 /* This is a memory hole */
3476 #endif /* CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID */
3478 int __meminit
early_pfn_to_nid(unsigned long pfn
)
3482 nid
= __early_pfn_to_nid(pfn
);
3485 /* just returns 0 */
3489 #ifdef CONFIG_NODES_SPAN_OTHER_NODES
3490 bool __meminit
early_pfn_in_nid(unsigned long pfn
, int node
)
3494 nid
= __early_pfn_to_nid(pfn
);
3495 if (nid
>= 0 && nid
!= node
)
3501 /* Basic iterator support to walk early_node_map[] */
3502 #define for_each_active_range_index_in_nid(i, nid) \
3503 for (i = first_active_region_index_in_nid(nid); i != -1; \
3504 i = next_active_region_index_in_nid(i, nid))
3507 * free_bootmem_with_active_regions - Call free_bootmem_node for each active range
3508 * @nid: The node to free memory on. If MAX_NUMNODES, all nodes are freed.
3509 * @max_low_pfn: The highest PFN that will be passed to free_bootmem_node
3511 * If an architecture guarantees that all ranges registered with
3512 * add_active_ranges() contain no holes and may be freed, this
3513 * this function may be used instead of calling free_bootmem() manually.
3515 void __init
free_bootmem_with_active_regions(int nid
,
3516 unsigned long max_low_pfn
)
3520 for_each_active_range_index_in_nid(i
, nid
) {
3521 unsigned long size_pages
= 0;
3522 unsigned long end_pfn
= early_node_map
[i
].end_pfn
;
3524 if (early_node_map
[i
].start_pfn
>= max_low_pfn
)
3527 if (end_pfn
> max_low_pfn
)
3528 end_pfn
= max_low_pfn
;
3530 size_pages
= end_pfn
- early_node_map
[i
].start_pfn
;
3531 free_bootmem_node(NODE_DATA(early_node_map
[i
].nid
),
3532 PFN_PHYS(early_node_map
[i
].start_pfn
),
3533 size_pages
<< PAGE_SHIFT
);
3537 int __init
add_from_early_node_map(struct range
*range
, int az
,
3538 int nr_range
, int nid
)
3543 /* need to go over early_node_map to find out good range for node */
3544 for_each_active_range_index_in_nid(i
, nid
) {
3545 start
= early_node_map
[i
].start_pfn
;
3546 end
= early_node_map
[i
].end_pfn
;
3547 nr_range
= add_range(range
, az
, nr_range
, start
, end
);
3552 #ifdef CONFIG_NO_BOOTMEM
3553 void * __init
__alloc_memory_core_early(int nid
, u64 size
, u64 align
,
3554 u64 goal
, u64 limit
)
3559 /* need to go over early_node_map to find out good range for node */
3560 for_each_active_range_index_in_nid(i
, nid
) {
3562 u64 ei_start
, ei_last
;
3564 ei_last
= early_node_map
[i
].end_pfn
;
3565 ei_last
<<= PAGE_SHIFT
;
3566 ei_start
= early_node_map
[i
].start_pfn
;
3567 ei_start
<<= PAGE_SHIFT
;
3568 addr
= find_early_area(ei_start
, ei_last
,
3569 goal
, limit
, size
, align
);
3575 printk(KERN_DEBUG
"alloc (nid=%d %llx - %llx) (%llx - %llx) %llx %llx => %llx\n",
3577 ei_start
, ei_last
, goal
, limit
, size
,
3581 ptr
= phys_to_virt(addr
);
3582 memset(ptr
, 0, size
);
3583 reserve_early_without_check(addr
, addr
+ size
, "BOOTMEM");
3592 void __init
work_with_active_regions(int nid
, work_fn_t work_fn
, void *data
)
3597 for_each_active_range_index_in_nid(i
, nid
) {
3598 ret
= work_fn(early_node_map
[i
].start_pfn
,
3599 early_node_map
[i
].end_pfn
, data
);
3605 * sparse_memory_present_with_active_regions - Call memory_present for each active range
3606 * @nid: The node to call memory_present for. If MAX_NUMNODES, all nodes will be used.
3608 * If an architecture guarantees that all ranges registered with
3609 * add_active_ranges() contain no holes and may be freed, this
3610 * function may be used instead of calling memory_present() manually.
3612 void __init
sparse_memory_present_with_active_regions(int nid
)
3616 for_each_active_range_index_in_nid(i
, nid
)
3617 memory_present(early_node_map
[i
].nid
,
3618 early_node_map
[i
].start_pfn
,
3619 early_node_map
[i
].end_pfn
);
3623 * get_pfn_range_for_nid - Return the start and end page frames for a node
3624 * @nid: The nid to return the range for. If MAX_NUMNODES, the min and max PFN are returned.
3625 * @start_pfn: Passed by reference. On return, it will have the node start_pfn.
3626 * @end_pfn: Passed by reference. On return, it will have the node end_pfn.
3628 * It returns the start and end page frame of a node based on information
3629 * provided by an arch calling add_active_range(). If called for a node
3630 * with no available memory, a warning is printed and the start and end
3633 void __meminit
get_pfn_range_for_nid(unsigned int nid
,
3634 unsigned long *start_pfn
, unsigned long *end_pfn
)
3640 for_each_active_range_index_in_nid(i
, nid
) {
3641 *start_pfn
= min(*start_pfn
, early_node_map
[i
].start_pfn
);
3642 *end_pfn
= max(*end_pfn
, early_node_map
[i
].end_pfn
);
3645 if (*start_pfn
== -1UL)
3650 * This finds a zone that can be used for ZONE_MOVABLE pages. The
3651 * assumption is made that zones within a node are ordered in monotonic
3652 * increasing memory addresses so that the "highest" populated zone is used
3654 static void __init
find_usable_zone_for_movable(void)
3657 for (zone_index
= MAX_NR_ZONES
- 1; zone_index
>= 0; zone_index
--) {
3658 if (zone_index
== ZONE_MOVABLE
)
3661 if (arch_zone_highest_possible_pfn
[zone_index
] >
3662 arch_zone_lowest_possible_pfn
[zone_index
])
3666 VM_BUG_ON(zone_index
== -1);
3667 movable_zone
= zone_index
;
3671 * The zone ranges provided by the architecture do not include ZONE_MOVABLE
3672 * because it is sized independant of architecture. Unlike the other zones,
3673 * the starting point for ZONE_MOVABLE is not fixed. It may be different
3674 * in each node depending on the size of each node and how evenly kernelcore
3675 * is distributed. This helper function adjusts the zone ranges
3676 * provided by the architecture for a given node by using the end of the
3677 * highest usable zone for ZONE_MOVABLE. This preserves the assumption that
3678 * zones within a node are in order of monotonic increases memory addresses
3680 static void __meminit
adjust_zone_range_for_zone_movable(int nid
,
3681 unsigned long zone_type
,
3682 unsigned long node_start_pfn
,
3683 unsigned long node_end_pfn
,
3684 unsigned long *zone_start_pfn
,
3685 unsigned long *zone_end_pfn
)
3687 /* Only adjust if ZONE_MOVABLE is on this node */
3688 if (zone_movable_pfn
[nid
]) {
3689 /* Size ZONE_MOVABLE */
3690 if (zone_type
== ZONE_MOVABLE
) {
3691 *zone_start_pfn
= zone_movable_pfn
[nid
];
3692 *zone_end_pfn
= min(node_end_pfn
,
3693 arch_zone_highest_possible_pfn
[movable_zone
]);
3695 /* Adjust for ZONE_MOVABLE starting within this range */
3696 } else if (*zone_start_pfn
< zone_movable_pfn
[nid
] &&
3697 *zone_end_pfn
> zone_movable_pfn
[nid
]) {
3698 *zone_end_pfn
= zone_movable_pfn
[nid
];
3700 /* Check if this whole range is within ZONE_MOVABLE */
3701 } else if (*zone_start_pfn
>= zone_movable_pfn
[nid
])
3702 *zone_start_pfn
= *zone_end_pfn
;
3707 * Return the number of pages a zone spans in a node, including holes
3708 * present_pages = zone_spanned_pages_in_node() - zone_absent_pages_in_node()
3710 static unsigned long __meminit
zone_spanned_pages_in_node(int nid
,
3711 unsigned long zone_type
,
3712 unsigned long *ignored
)
3714 unsigned long node_start_pfn
, node_end_pfn
;
3715 unsigned long zone_start_pfn
, zone_end_pfn
;
3717 /* Get the start and end of the node and zone */
3718 get_pfn_range_for_nid(nid
, &node_start_pfn
, &node_end_pfn
);
3719 zone_start_pfn
= arch_zone_lowest_possible_pfn
[zone_type
];
3720 zone_end_pfn
= arch_zone_highest_possible_pfn
[zone_type
];
3721 adjust_zone_range_for_zone_movable(nid
, zone_type
,
3722 node_start_pfn
, node_end_pfn
,
3723 &zone_start_pfn
, &zone_end_pfn
);
3725 /* Check that this node has pages within the zone's required range */
3726 if (zone_end_pfn
< node_start_pfn
|| zone_start_pfn
> node_end_pfn
)
3729 /* Move the zone boundaries inside the node if necessary */
3730 zone_end_pfn
= min(zone_end_pfn
, node_end_pfn
);
3731 zone_start_pfn
= max(zone_start_pfn
, node_start_pfn
);
3733 /* Return the spanned pages */
3734 return zone_end_pfn
- zone_start_pfn
;
3738 * Return the number of holes in a range on a node. If nid is MAX_NUMNODES,
3739 * then all holes in the requested range will be accounted for.
3741 unsigned long __meminit
__absent_pages_in_range(int nid
,
3742 unsigned long range_start_pfn
,
3743 unsigned long range_end_pfn
)
3746 unsigned long prev_end_pfn
= 0, hole_pages
= 0;
3747 unsigned long start_pfn
;
3749 /* Find the end_pfn of the first active range of pfns in the node */
3750 i
= first_active_region_index_in_nid(nid
);
3754 prev_end_pfn
= min(early_node_map
[i
].start_pfn
, range_end_pfn
);
3756 /* Account for ranges before physical memory on this node */
3757 if (early_node_map
[i
].start_pfn
> range_start_pfn
)
3758 hole_pages
= prev_end_pfn
- range_start_pfn
;
3760 /* Find all holes for the zone within the node */
3761 for (; i
!= -1; i
= next_active_region_index_in_nid(i
, nid
)) {
3763 /* No need to continue if prev_end_pfn is outside the zone */
3764 if (prev_end_pfn
>= range_end_pfn
)
3767 /* Make sure the end of the zone is not within the hole */
3768 start_pfn
= min(early_node_map
[i
].start_pfn
, range_end_pfn
);
3769 prev_end_pfn
= max(prev_end_pfn
, range_start_pfn
);
3771 /* Update the hole size cound and move on */
3772 if (start_pfn
> range_start_pfn
) {
3773 BUG_ON(prev_end_pfn
> start_pfn
);
3774 hole_pages
+= start_pfn
- prev_end_pfn
;
3776 prev_end_pfn
= early_node_map
[i
].end_pfn
;
3779 /* Account for ranges past physical memory on this node */
3780 if (range_end_pfn
> prev_end_pfn
)
3781 hole_pages
+= range_end_pfn
-
3782 max(range_start_pfn
, prev_end_pfn
);
3788 * absent_pages_in_range - Return number of page frames in holes within a range
3789 * @start_pfn: The start PFN to start searching for holes
3790 * @end_pfn: The end PFN to stop searching for holes
3792 * It returns the number of pages frames in memory holes within a range.
3794 unsigned long __init
absent_pages_in_range(unsigned long start_pfn
,
3795 unsigned long end_pfn
)
3797 return __absent_pages_in_range(MAX_NUMNODES
, start_pfn
, end_pfn
);
3800 /* Return the number of page frames in holes in a zone on a node */
3801 static unsigned long __meminit
zone_absent_pages_in_node(int nid
,
3802 unsigned long zone_type
,
3803 unsigned long *ignored
)
3805 unsigned long node_start_pfn
, node_end_pfn
;
3806 unsigned long zone_start_pfn
, zone_end_pfn
;
3808 get_pfn_range_for_nid(nid
, &node_start_pfn
, &node_end_pfn
);
3809 zone_start_pfn
= max(arch_zone_lowest_possible_pfn
[zone_type
],
3811 zone_end_pfn
= min(arch_zone_highest_possible_pfn
[zone_type
],
3814 adjust_zone_range_for_zone_movable(nid
, zone_type
,
3815 node_start_pfn
, node_end_pfn
,
3816 &zone_start_pfn
, &zone_end_pfn
);
3817 return __absent_pages_in_range(nid
, zone_start_pfn
, zone_end_pfn
);
3821 static inline unsigned long __meminit
zone_spanned_pages_in_node(int nid
,
3822 unsigned long zone_type
,
3823 unsigned long *zones_size
)
3825 return zones_size
[zone_type
];
3828 static inline unsigned long __meminit
zone_absent_pages_in_node(int nid
,
3829 unsigned long zone_type
,
3830 unsigned long *zholes_size
)
3835 return zholes_size
[zone_type
];
3840 static void __meminit
calculate_node_totalpages(struct pglist_data
*pgdat
,
3841 unsigned long *zones_size
, unsigned long *zholes_size
)
3843 unsigned long realtotalpages
, totalpages
= 0;
3846 for (i
= 0; i
< MAX_NR_ZONES
; i
++)
3847 totalpages
+= zone_spanned_pages_in_node(pgdat
->node_id
, i
,
3849 pgdat
->node_spanned_pages
= totalpages
;
3851 realtotalpages
= totalpages
;
3852 for (i
= 0; i
< MAX_NR_ZONES
; i
++)
3854 zone_absent_pages_in_node(pgdat
->node_id
, i
,
3856 pgdat
->node_present_pages
= realtotalpages
;
3857 printk(KERN_DEBUG
"On node %d totalpages: %lu\n", pgdat
->node_id
,
3861 #ifndef CONFIG_SPARSEMEM
3863 * Calculate the size of the zone->blockflags rounded to an unsigned long
3864 * Start by making sure zonesize is a multiple of pageblock_order by rounding
3865 * up. Then use 1 NR_PAGEBLOCK_BITS worth of bits per pageblock, finally
3866 * round what is now in bits to nearest long in bits, then return it in
3869 static unsigned long __init
usemap_size(unsigned long zonesize
)
3871 unsigned long usemapsize
;
3873 usemapsize
= roundup(zonesize
, pageblock_nr_pages
);
3874 usemapsize
= usemapsize
>> pageblock_order
;
3875 usemapsize
*= NR_PAGEBLOCK_BITS
;
3876 usemapsize
= roundup(usemapsize
, 8 * sizeof(unsigned long));
3878 return usemapsize
/ 8;
3881 static void __init
setup_usemap(struct pglist_data
*pgdat
,
3882 struct zone
*zone
, unsigned long zonesize
)
3884 unsigned long usemapsize
= usemap_size(zonesize
);
3885 zone
->pageblock_flags
= NULL
;
3887 zone
->pageblock_flags
= alloc_bootmem_node(pgdat
, usemapsize
);
3890 static void inline setup_usemap(struct pglist_data
*pgdat
,
3891 struct zone
*zone
, unsigned long zonesize
) {}
3892 #endif /* CONFIG_SPARSEMEM */
3894 #ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
3896 /* Return a sensible default order for the pageblock size. */
3897 static inline int pageblock_default_order(void)
3899 if (HPAGE_SHIFT
> PAGE_SHIFT
)
3900 return HUGETLB_PAGE_ORDER
;
3905 /* Initialise the number of pages represented by NR_PAGEBLOCK_BITS */
3906 static inline void __init
set_pageblock_order(unsigned int order
)
3908 /* Check that pageblock_nr_pages has not already been setup */
3909 if (pageblock_order
)
3913 * Assume the largest contiguous order of interest is a huge page.
3914 * This value may be variable depending on boot parameters on IA64
3916 pageblock_order
= order
;
3918 #else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
3921 * When CONFIG_HUGETLB_PAGE_SIZE_VARIABLE is not set, set_pageblock_order()
3922 * and pageblock_default_order() are unused as pageblock_order is set
3923 * at compile-time. See include/linux/pageblock-flags.h for the values of
3924 * pageblock_order based on the kernel config
3926 static inline int pageblock_default_order(unsigned int order
)
3930 #define set_pageblock_order(x) do {} while (0)
3932 #endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
3935 * Set up the zone data structures:
3936 * - mark all pages reserved
3937 * - mark all memory queues empty
3938 * - clear the memory bitmaps
3940 static void __paginginit
free_area_init_core(struct pglist_data
*pgdat
,
3941 unsigned long *zones_size
, unsigned long *zholes_size
)
3944 int nid
= pgdat
->node_id
;
3945 unsigned long zone_start_pfn
= pgdat
->node_start_pfn
;
3948 pgdat_resize_init(pgdat
);
3949 pgdat
->nr_zones
= 0;
3950 init_waitqueue_head(&pgdat
->kswapd_wait
);
3951 pgdat
->kswapd_max_order
= 0;
3952 pgdat_page_cgroup_init(pgdat
);
3954 for (j
= 0; j
< MAX_NR_ZONES
; j
++) {
3955 struct zone
*zone
= pgdat
->node_zones
+ j
;
3956 unsigned long size
, realsize
, memmap_pages
;
3959 size
= zone_spanned_pages_in_node(nid
, j
, zones_size
);
3960 realsize
= size
- zone_absent_pages_in_node(nid
, j
,
3964 * Adjust realsize so that it accounts for how much memory
3965 * is used by this zone for memmap. This affects the watermark
3966 * and per-cpu initialisations
3969 PAGE_ALIGN(size
* sizeof(struct page
)) >> PAGE_SHIFT
;
3970 if (realsize
>= memmap_pages
) {
3971 realsize
-= memmap_pages
;
3974 " %s zone: %lu pages used for memmap\n",
3975 zone_names
[j
], memmap_pages
);
3978 " %s zone: %lu pages exceeds realsize %lu\n",
3979 zone_names
[j
], memmap_pages
, realsize
);
3981 /* Account for reserved pages */
3982 if (j
== 0 && realsize
> dma_reserve
) {
3983 realsize
-= dma_reserve
;
3984 printk(KERN_DEBUG
" %s zone: %lu pages reserved\n",
3985 zone_names
[0], dma_reserve
);
3988 if (!is_highmem_idx(j
))
3989 nr_kernel_pages
+= realsize
;
3990 nr_all_pages
+= realsize
;
3992 zone
->spanned_pages
= size
;
3993 zone
->present_pages
= realsize
;
3996 zone
->min_unmapped_pages
= (realsize
*sysctl_min_unmapped_ratio
)
3998 zone
->min_slab_pages
= (realsize
* sysctl_min_slab_ratio
) / 100;
4000 zone
->name
= zone_names
[j
];
4001 spin_lock_init(&zone
->lock
);
4002 spin_lock_init(&zone
->lru_lock
);
4003 zone_seqlock_init(zone
);
4004 zone
->zone_pgdat
= pgdat
;
4006 zone
->prev_priority
= DEF_PRIORITY
;
4008 zone_pcp_init(zone
);
4010 INIT_LIST_HEAD(&zone
->lru
[l
].list
);
4011 zone
->reclaim_stat
.nr_saved_scan
[l
] = 0;
4013 zone
->reclaim_stat
.recent_rotated
[0] = 0;
4014 zone
->reclaim_stat
.recent_rotated
[1] = 0;
4015 zone
->reclaim_stat
.recent_scanned
[0] = 0;
4016 zone
->reclaim_stat
.recent_scanned
[1] = 0;
4017 zap_zone_vm_stats(zone
);
4022 set_pageblock_order(pageblock_default_order());
4023 setup_usemap(pgdat
, zone
, size
);
4024 ret
= init_currently_empty_zone(zone
, zone_start_pfn
,
4025 size
, MEMMAP_EARLY
);
4027 memmap_init(size
, nid
, j
, zone_start_pfn
);
4028 zone_start_pfn
+= size
;
4032 static void __init_refok
alloc_node_mem_map(struct pglist_data
*pgdat
)
4034 /* Skip empty nodes */
4035 if (!pgdat
->node_spanned_pages
)
4038 #ifdef CONFIG_FLAT_NODE_MEM_MAP
4039 /* ia64 gets its own node_mem_map, before this, without bootmem */
4040 if (!pgdat
->node_mem_map
) {
4041 unsigned long size
, start
, end
;
4045 * The zone's endpoints aren't required to be MAX_ORDER
4046 * aligned but the node_mem_map endpoints must be in order
4047 * for the buddy allocator to function correctly.
4049 start
= pgdat
->node_start_pfn
& ~(MAX_ORDER_NR_PAGES
- 1);
4050 end
= pgdat
->node_start_pfn
+ pgdat
->node_spanned_pages
;
4051 end
= ALIGN(end
, MAX_ORDER_NR_PAGES
);
4052 size
= (end
- start
) * sizeof(struct page
);
4053 map
= alloc_remap(pgdat
->node_id
, size
);
4055 map
= alloc_bootmem_node(pgdat
, size
);
4056 pgdat
->node_mem_map
= map
+ (pgdat
->node_start_pfn
- start
);
4058 #ifndef CONFIG_NEED_MULTIPLE_NODES
4060 * With no DISCONTIG, the global mem_map is just set as node 0's
4062 if (pgdat
== NODE_DATA(0)) {
4063 mem_map
= NODE_DATA(0)->node_mem_map
;
4064 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
4065 if (page_to_pfn(mem_map
) != pgdat
->node_start_pfn
)
4066 mem_map
-= (pgdat
->node_start_pfn
- ARCH_PFN_OFFSET
);
4067 #endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
4070 #endif /* CONFIG_FLAT_NODE_MEM_MAP */
4073 void __paginginit
free_area_init_node(int nid
, unsigned long *zones_size
,
4074 unsigned long node_start_pfn
, unsigned long *zholes_size
)
4076 pg_data_t
*pgdat
= NODE_DATA(nid
);
4078 pgdat
->node_id
= nid
;
4079 pgdat
->node_start_pfn
= node_start_pfn
;
4080 calculate_node_totalpages(pgdat
, zones_size
, zholes_size
);
4082 alloc_node_mem_map(pgdat
);
4083 #ifdef CONFIG_FLAT_NODE_MEM_MAP
4084 printk(KERN_DEBUG
"free_area_init_node: node %d, pgdat %08lx, node_mem_map %08lx\n",
4085 nid
, (unsigned long)pgdat
,
4086 (unsigned long)pgdat
->node_mem_map
);
4089 free_area_init_core(pgdat
, zones_size
, zholes_size
);
4092 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
4094 #if MAX_NUMNODES > 1
4096 * Figure out the number of possible node ids.
4098 static void __init
setup_nr_node_ids(void)
4101 unsigned int highest
= 0;
4103 for_each_node_mask(node
, node_possible_map
)
4105 nr_node_ids
= highest
+ 1;
4108 static inline void setup_nr_node_ids(void)
4114 * add_active_range - Register a range of PFNs backed by physical memory
4115 * @nid: The node ID the range resides on
4116 * @start_pfn: The start PFN of the available physical memory
4117 * @end_pfn: The end PFN of the available physical memory
4119 * These ranges are stored in an early_node_map[] and later used by
4120 * free_area_init_nodes() to calculate zone sizes and holes. If the
4121 * range spans a memory hole, it is up to the architecture to ensure
4122 * the memory is not freed by the bootmem allocator. If possible
4123 * the range being registered will be merged with existing ranges.
4125 void __init
add_active_range(unsigned int nid
, unsigned long start_pfn
,
4126 unsigned long end_pfn
)
4130 mminit_dprintk(MMINIT_TRACE
, "memory_register",
4131 "Entering add_active_range(%d, %#lx, %#lx) "
4132 "%d entries of %d used\n",
4133 nid
, start_pfn
, end_pfn
,
4134 nr_nodemap_entries
, MAX_ACTIVE_REGIONS
);
4136 mminit_validate_memmodel_limits(&start_pfn
, &end_pfn
);
4138 /* Merge with existing active regions if possible */
4139 for (i
= 0; i
< nr_nodemap_entries
; i
++) {
4140 if (early_node_map
[i
].nid
!= nid
)
4143 /* Skip if an existing region covers this new one */
4144 if (start_pfn
>= early_node_map
[i
].start_pfn
&&
4145 end_pfn
<= early_node_map
[i
].end_pfn
)
4148 /* Merge forward if suitable */
4149 if (start_pfn
<= early_node_map
[i
].end_pfn
&&
4150 end_pfn
> early_node_map
[i
].end_pfn
) {
4151 early_node_map
[i
].end_pfn
= end_pfn
;
4155 /* Merge backward if suitable */
4156 if (start_pfn
< early_node_map
[i
].start_pfn
&&
4157 end_pfn
>= early_node_map
[i
].start_pfn
) {
4158 early_node_map
[i
].start_pfn
= start_pfn
;
4163 /* Check that early_node_map is large enough */
4164 if (i
>= MAX_ACTIVE_REGIONS
) {
4165 printk(KERN_CRIT
"More than %d memory regions, truncating\n",
4166 MAX_ACTIVE_REGIONS
);
4170 early_node_map
[i
].nid
= nid
;
4171 early_node_map
[i
].start_pfn
= start_pfn
;
4172 early_node_map
[i
].end_pfn
= end_pfn
;
4173 nr_nodemap_entries
= i
+ 1;
4177 * remove_active_range - Shrink an existing registered range of PFNs
4178 * @nid: The node id the range is on that should be shrunk
4179 * @start_pfn: The new PFN of the range
4180 * @end_pfn: The new PFN of the range
4182 * i386 with NUMA use alloc_remap() to store a node_mem_map on a local node.
4183 * The map is kept near the end physical page range that has already been
4184 * registered. This function allows an arch to shrink an existing registered
4187 void __init
remove_active_range(unsigned int nid
, unsigned long start_pfn
,
4188 unsigned long end_pfn
)
4193 printk(KERN_DEBUG
"remove_active_range (%d, %lu, %lu)\n",
4194 nid
, start_pfn
, end_pfn
);
4196 /* Find the old active region end and shrink */
4197 for_each_active_range_index_in_nid(i
, nid
) {
4198 if (early_node_map
[i
].start_pfn
>= start_pfn
&&
4199 early_node_map
[i
].end_pfn
<= end_pfn
) {
4201 early_node_map
[i
].start_pfn
= 0;
4202 early_node_map
[i
].end_pfn
= 0;
4206 if (early_node_map
[i
].start_pfn
< start_pfn
&&
4207 early_node_map
[i
].end_pfn
> start_pfn
) {
4208 unsigned long temp_end_pfn
= early_node_map
[i
].end_pfn
;
4209 early_node_map
[i
].end_pfn
= start_pfn
;
4210 if (temp_end_pfn
> end_pfn
)
4211 add_active_range(nid
, end_pfn
, temp_end_pfn
);
4214 if (early_node_map
[i
].start_pfn
>= start_pfn
&&
4215 early_node_map
[i
].end_pfn
> end_pfn
&&
4216 early_node_map
[i
].start_pfn
< end_pfn
) {
4217 early_node_map
[i
].start_pfn
= end_pfn
;
4225 /* remove the blank ones */
4226 for (i
= nr_nodemap_entries
- 1; i
> 0; i
--) {
4227 if (early_node_map
[i
].nid
!= nid
)
4229 if (early_node_map
[i
].end_pfn
)
4231 /* we found it, get rid of it */
4232 for (j
= i
; j
< nr_nodemap_entries
- 1; j
++)
4233 memcpy(&early_node_map
[j
], &early_node_map
[j
+1],
4234 sizeof(early_node_map
[j
]));
4235 j
= nr_nodemap_entries
- 1;
4236 memset(&early_node_map
[j
], 0, sizeof(early_node_map
[j
]));
4237 nr_nodemap_entries
--;
4242 * remove_all_active_ranges - Remove all currently registered regions
4244 * During discovery, it may be found that a table like SRAT is invalid
4245 * and an alternative discovery method must be used. This function removes
4246 * all currently registered regions.
4248 void __init
remove_all_active_ranges(void)
4250 memset(early_node_map
, 0, sizeof(early_node_map
));
4251 nr_nodemap_entries
= 0;
4254 /* Compare two active node_active_regions */
4255 static int __init
cmp_node_active_region(const void *a
, const void *b
)
4257 struct node_active_region
*arange
= (struct node_active_region
*)a
;
4258 struct node_active_region
*brange
= (struct node_active_region
*)b
;
4260 /* Done this way to avoid overflows */
4261 if (arange
->start_pfn
> brange
->start_pfn
)
4263 if (arange
->start_pfn
< brange
->start_pfn
)
4269 /* sort the node_map by start_pfn */
4270 void __init
sort_node_map(void)
4272 sort(early_node_map
, (size_t)nr_nodemap_entries
,
4273 sizeof(struct node_active_region
),
4274 cmp_node_active_region
, NULL
);
4277 /* Find the lowest pfn for a node */
4278 static unsigned long __init
find_min_pfn_for_node(int nid
)
4281 unsigned long min_pfn
= ULONG_MAX
;
4283 /* Assuming a sorted map, the first range found has the starting pfn */
4284 for_each_active_range_index_in_nid(i
, nid
)
4285 min_pfn
= min(min_pfn
, early_node_map
[i
].start_pfn
);
4287 if (min_pfn
== ULONG_MAX
) {
4289 "Could not find start_pfn for node %d\n", nid
);
4297 * find_min_pfn_with_active_regions - Find the minimum PFN registered
4299 * It returns the minimum PFN based on information provided via
4300 * add_active_range().
4302 unsigned long __init
find_min_pfn_with_active_regions(void)
4304 return find_min_pfn_for_node(MAX_NUMNODES
);
4308 * early_calculate_totalpages()
4309 * Sum pages in active regions for movable zone.
4310 * Populate N_HIGH_MEMORY for calculating usable_nodes.
4312 static unsigned long __init
early_calculate_totalpages(void)
4315 unsigned long totalpages
= 0;
4317 for (i
= 0; i
< nr_nodemap_entries
; i
++) {
4318 unsigned long pages
= early_node_map
[i
].end_pfn
-
4319 early_node_map
[i
].start_pfn
;
4320 totalpages
+= pages
;
4322 node_set_state(early_node_map
[i
].nid
, N_HIGH_MEMORY
);
4328 * Find the PFN the Movable zone begins in each node. Kernel memory
4329 * is spread evenly between nodes as long as the nodes have enough
4330 * memory. When they don't, some nodes will have more kernelcore than
4333 static void __init
find_zone_movable_pfns_for_nodes(unsigned long *movable_pfn
)
4336 unsigned long usable_startpfn
;
4337 unsigned long kernelcore_node
, kernelcore_remaining
;
4338 /* save the state before borrow the nodemask */
4339 nodemask_t saved_node_state
= node_states
[N_HIGH_MEMORY
];
4340 unsigned long totalpages
= early_calculate_totalpages();
4341 int usable_nodes
= nodes_weight(node_states
[N_HIGH_MEMORY
]);
4344 * If movablecore was specified, calculate what size of
4345 * kernelcore that corresponds so that memory usable for
4346 * any allocation type is evenly spread. If both kernelcore
4347 * and movablecore are specified, then the value of kernelcore
4348 * will be used for required_kernelcore if it's greater than
4349 * what movablecore would have allowed.
4351 if (required_movablecore
) {
4352 unsigned long corepages
;
4355 * Round-up so that ZONE_MOVABLE is at least as large as what
4356 * was requested by the user
4358 required_movablecore
=
4359 roundup(required_movablecore
, MAX_ORDER_NR_PAGES
);
4360 corepages
= totalpages
- required_movablecore
;
4362 required_kernelcore
= max(required_kernelcore
, corepages
);
4365 /* If kernelcore was not specified, there is no ZONE_MOVABLE */
4366 if (!required_kernelcore
)
4369 /* usable_startpfn is the lowest possible pfn ZONE_MOVABLE can be at */
4370 find_usable_zone_for_movable();
4371 usable_startpfn
= arch_zone_lowest_possible_pfn
[movable_zone
];
4374 /* Spread kernelcore memory as evenly as possible throughout nodes */
4375 kernelcore_node
= required_kernelcore
/ usable_nodes
;
4376 for_each_node_state(nid
, N_HIGH_MEMORY
) {
4378 * Recalculate kernelcore_node if the division per node
4379 * now exceeds what is necessary to satisfy the requested
4380 * amount of memory for the kernel
4382 if (required_kernelcore
< kernelcore_node
)
4383 kernelcore_node
= required_kernelcore
/ usable_nodes
;
4386 * As the map is walked, we track how much memory is usable
4387 * by the kernel using kernelcore_remaining. When it is
4388 * 0, the rest of the node is usable by ZONE_MOVABLE
4390 kernelcore_remaining
= kernelcore_node
;
4392 /* Go through each range of PFNs within this node */
4393 for_each_active_range_index_in_nid(i
, nid
) {
4394 unsigned long start_pfn
, end_pfn
;
4395 unsigned long size_pages
;
4397 start_pfn
= max(early_node_map
[i
].start_pfn
,
4398 zone_movable_pfn
[nid
]);
4399 end_pfn
= early_node_map
[i
].end_pfn
;
4400 if (start_pfn
>= end_pfn
)
4403 /* Account for what is only usable for kernelcore */
4404 if (start_pfn
< usable_startpfn
) {
4405 unsigned long kernel_pages
;
4406 kernel_pages
= min(end_pfn
, usable_startpfn
)
4409 kernelcore_remaining
-= min(kernel_pages
,
4410 kernelcore_remaining
);
4411 required_kernelcore
-= min(kernel_pages
,
4412 required_kernelcore
);
4414 /* Continue if range is now fully accounted */
4415 if (end_pfn
<= usable_startpfn
) {
4418 * Push zone_movable_pfn to the end so
4419 * that if we have to rebalance
4420 * kernelcore across nodes, we will
4421 * not double account here
4423 zone_movable_pfn
[nid
] = end_pfn
;
4426 start_pfn
= usable_startpfn
;
4430 * The usable PFN range for ZONE_MOVABLE is from
4431 * start_pfn->end_pfn. Calculate size_pages as the
4432 * number of pages used as kernelcore
4434 size_pages
= end_pfn
- start_pfn
;
4435 if (size_pages
> kernelcore_remaining
)
4436 size_pages
= kernelcore_remaining
;
4437 zone_movable_pfn
[nid
] = start_pfn
+ size_pages
;
4440 * Some kernelcore has been met, update counts and
4441 * break if the kernelcore for this node has been
4444 required_kernelcore
-= min(required_kernelcore
,
4446 kernelcore_remaining
-= size_pages
;
4447 if (!kernelcore_remaining
)
4453 * If there is still required_kernelcore, we do another pass with one
4454 * less node in the count. This will push zone_movable_pfn[nid] further
4455 * along on the nodes that still have memory until kernelcore is
4459 if (usable_nodes
&& required_kernelcore
> usable_nodes
)
4462 /* Align start of ZONE_MOVABLE on all nids to MAX_ORDER_NR_PAGES */
4463 for (nid
= 0; nid
< MAX_NUMNODES
; nid
++)
4464 zone_movable_pfn
[nid
] =
4465 roundup(zone_movable_pfn
[nid
], MAX_ORDER_NR_PAGES
);
4468 /* restore the node_state */
4469 node_states
[N_HIGH_MEMORY
] = saved_node_state
;
4472 /* Any regular memory on that node ? */
4473 static void check_for_regular_memory(pg_data_t
*pgdat
)
4475 #ifdef CONFIG_HIGHMEM
4476 enum zone_type zone_type
;
4478 for (zone_type
= 0; zone_type
<= ZONE_NORMAL
; zone_type
++) {
4479 struct zone
*zone
= &pgdat
->node_zones
[zone_type
];
4480 if (zone
->present_pages
)
4481 node_set_state(zone_to_nid(zone
), N_NORMAL_MEMORY
);
4487 * free_area_init_nodes - Initialise all pg_data_t and zone data
4488 * @max_zone_pfn: an array of max PFNs for each zone
4490 * This will call free_area_init_node() for each active node in the system.
4491 * Using the page ranges provided by add_active_range(), the size of each
4492 * zone in each node and their holes is calculated. If the maximum PFN
4493 * between two adjacent zones match, it is assumed that the zone is empty.
4494 * For example, if arch_max_dma_pfn == arch_max_dma32_pfn, it is assumed
4495 * that arch_max_dma32_pfn has no pages. It is also assumed that a zone
4496 * starts where the previous one ended. For example, ZONE_DMA32 starts
4497 * at arch_max_dma_pfn.
4499 void __init
free_area_init_nodes(unsigned long *max_zone_pfn
)
4504 /* Sort early_node_map as initialisation assumes it is sorted */
4507 /* Record where the zone boundaries are */
4508 memset(arch_zone_lowest_possible_pfn
, 0,
4509 sizeof(arch_zone_lowest_possible_pfn
));
4510 memset(arch_zone_highest_possible_pfn
, 0,
4511 sizeof(arch_zone_highest_possible_pfn
));
4512 arch_zone_lowest_possible_pfn
[0] = find_min_pfn_with_active_regions();
4513 arch_zone_highest_possible_pfn
[0] = max_zone_pfn
[0];
4514 for (i
= 1; i
< MAX_NR_ZONES
; i
++) {
4515 if (i
== ZONE_MOVABLE
)
4517 arch_zone_lowest_possible_pfn
[i
] =
4518 arch_zone_highest_possible_pfn
[i
-1];
4519 arch_zone_highest_possible_pfn
[i
] =
4520 max(max_zone_pfn
[i
], arch_zone_lowest_possible_pfn
[i
]);
4522 arch_zone_lowest_possible_pfn
[ZONE_MOVABLE
] = 0;
4523 arch_zone_highest_possible_pfn
[ZONE_MOVABLE
] = 0;
4525 /* Find the PFNs that ZONE_MOVABLE begins at in each node */
4526 memset(zone_movable_pfn
, 0, sizeof(zone_movable_pfn
));
4527 find_zone_movable_pfns_for_nodes(zone_movable_pfn
);
4529 /* Print out the zone ranges */
4530 printk("Zone PFN ranges:\n");
4531 for (i
= 0; i
< MAX_NR_ZONES
; i
++) {
4532 if (i
== ZONE_MOVABLE
)
4534 printk(" %-8s ", zone_names
[i
]);
4535 if (arch_zone_lowest_possible_pfn
[i
] ==
4536 arch_zone_highest_possible_pfn
[i
])
4539 printk("%0#10lx -> %0#10lx\n",
4540 arch_zone_lowest_possible_pfn
[i
],
4541 arch_zone_highest_possible_pfn
[i
]);
4544 /* Print out the PFNs ZONE_MOVABLE begins at in each node */
4545 printk("Movable zone start PFN for each node\n");
4546 for (i
= 0; i
< MAX_NUMNODES
; i
++) {
4547 if (zone_movable_pfn
[i
])
4548 printk(" Node %d: %lu\n", i
, zone_movable_pfn
[i
]);
4551 /* Print out the early_node_map[] */
4552 printk("early_node_map[%d] active PFN ranges\n", nr_nodemap_entries
);
4553 for (i
= 0; i
< nr_nodemap_entries
; i
++)
4554 printk(" %3d: %0#10lx -> %0#10lx\n", early_node_map
[i
].nid
,
4555 early_node_map
[i
].start_pfn
,
4556 early_node_map
[i
].end_pfn
);
4558 /* Initialise every node */
4559 mminit_verify_pageflags_layout();
4560 setup_nr_node_ids();
4561 for_each_online_node(nid
) {
4562 pg_data_t
*pgdat
= NODE_DATA(nid
);
4563 free_area_init_node(nid
, NULL
,
4564 find_min_pfn_for_node(nid
), NULL
);
4566 /* Any memory on that node */
4567 if (pgdat
->node_present_pages
)
4568 node_set_state(nid
, N_HIGH_MEMORY
);
4569 check_for_regular_memory(pgdat
);
4573 static int __init
cmdline_parse_core(char *p
, unsigned long *core
)
4575 unsigned long long coremem
;
4579 coremem
= memparse(p
, &p
);
4580 *core
= coremem
>> PAGE_SHIFT
;
4582 /* Paranoid check that UL is enough for the coremem value */
4583 WARN_ON((coremem
>> PAGE_SHIFT
) > ULONG_MAX
);
4589 * kernelcore=size sets the amount of memory for use for allocations that
4590 * cannot be reclaimed or migrated.
4592 static int __init
cmdline_parse_kernelcore(char *p
)
4594 return cmdline_parse_core(p
, &required_kernelcore
);
4598 * movablecore=size sets the amount of memory for use for allocations that
4599 * can be reclaimed or migrated.
4601 static int __init
cmdline_parse_movablecore(char *p
)
4603 return cmdline_parse_core(p
, &required_movablecore
);
4606 early_param("kernelcore", cmdline_parse_kernelcore
);
4607 early_param("movablecore", cmdline_parse_movablecore
);
4609 #endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
4612 * set_dma_reserve - set the specified number of pages reserved in the first zone
4613 * @new_dma_reserve: The number of pages to mark reserved
4615 * The per-cpu batchsize and zone watermarks are determined by present_pages.
4616 * In the DMA zone, a significant percentage may be consumed by kernel image
4617 * and other unfreeable allocations which can skew the watermarks badly. This
4618 * function may optionally be used to account for unfreeable pages in the
4619 * first zone (e.g., ZONE_DMA). The effect will be lower watermarks and
4620 * smaller per-cpu batchsize.
4622 void __init
set_dma_reserve(unsigned long new_dma_reserve
)
4624 dma_reserve
= new_dma_reserve
;
4627 #ifndef CONFIG_NEED_MULTIPLE_NODES
4628 struct pglist_data __refdata contig_page_data
= {
4629 #ifndef CONFIG_NO_BOOTMEM
4630 .bdata
= &bootmem_node_data
[0]
4633 EXPORT_SYMBOL(contig_page_data
);
4636 void __init
free_area_init(unsigned long *zones_size
)
4638 free_area_init_node(0, zones_size
,
4639 __pa(PAGE_OFFSET
) >> PAGE_SHIFT
, NULL
);
4642 static int page_alloc_cpu_notify(struct notifier_block
*self
,
4643 unsigned long action
, void *hcpu
)
4645 int cpu
= (unsigned long)hcpu
;
4647 if (action
== CPU_DEAD
|| action
== CPU_DEAD_FROZEN
) {
4651 * Spill the event counters of the dead processor
4652 * into the current processors event counters.
4653 * This artificially elevates the count of the current
4656 vm_events_fold_cpu(cpu
);
4659 * Zero the differential counters of the dead processor
4660 * so that the vm statistics are consistent.
4662 * This is only okay since the processor is dead and cannot
4663 * race with what we are doing.
4665 refresh_cpu_vm_stats(cpu
);
4670 void __init
page_alloc_init(void)
4672 hotcpu_notifier(page_alloc_cpu_notify
, 0);
4676 * calculate_totalreserve_pages - called when sysctl_lower_zone_reserve_ratio
4677 * or min_free_kbytes changes.
4679 static void calculate_totalreserve_pages(void)
4681 struct pglist_data
*pgdat
;
4682 unsigned long reserve_pages
= 0;
4683 enum zone_type i
, j
;
4685 for_each_online_pgdat(pgdat
) {
4686 for (i
= 0; i
< MAX_NR_ZONES
; i
++) {
4687 struct zone
*zone
= pgdat
->node_zones
+ i
;
4688 unsigned long max
= 0;
4690 /* Find valid and maximum lowmem_reserve in the zone */
4691 for (j
= i
; j
< MAX_NR_ZONES
; j
++) {
4692 if (zone
->lowmem_reserve
[j
] > max
)
4693 max
= zone
->lowmem_reserve
[j
];
4696 /* we treat the high watermark as reserved pages. */
4697 max
+= high_wmark_pages(zone
);
4699 if (max
> zone
->present_pages
)
4700 max
= zone
->present_pages
;
4701 reserve_pages
+= max
;
4704 totalreserve_pages
= reserve_pages
;
4708 * setup_per_zone_lowmem_reserve - called whenever
4709 * sysctl_lower_zone_reserve_ratio changes. Ensures that each zone
4710 * has a correct pages reserved value, so an adequate number of
4711 * pages are left in the zone after a successful __alloc_pages().
4713 static void setup_per_zone_lowmem_reserve(void)
4715 struct pglist_data
*pgdat
;
4716 enum zone_type j
, idx
;
4718 for_each_online_pgdat(pgdat
) {
4719 for (j
= 0; j
< MAX_NR_ZONES
; j
++) {
4720 struct zone
*zone
= pgdat
->node_zones
+ j
;
4721 unsigned long present_pages
= zone
->present_pages
;
4723 zone
->lowmem_reserve
[j
] = 0;
4727 struct zone
*lower_zone
;
4731 if (sysctl_lowmem_reserve_ratio
[idx
] < 1)
4732 sysctl_lowmem_reserve_ratio
[idx
] = 1;
4734 lower_zone
= pgdat
->node_zones
+ idx
;
4735 lower_zone
->lowmem_reserve
[j
] = present_pages
/
4736 sysctl_lowmem_reserve_ratio
[idx
];
4737 present_pages
+= lower_zone
->present_pages
;
4742 /* update totalreserve_pages */
4743 calculate_totalreserve_pages();
4747 * setup_per_zone_wmarks - called when min_free_kbytes changes
4748 * or when memory is hot-{added|removed}
4750 * Ensures that the watermark[min,low,high] values for each zone are set
4751 * correctly with respect to min_free_kbytes.
4753 void setup_per_zone_wmarks(void)
4755 unsigned long pages_min
= min_free_kbytes
>> (PAGE_SHIFT
- 10);
4756 unsigned long lowmem_pages
= 0;
4758 unsigned long flags
;
4760 /* Calculate total number of !ZONE_HIGHMEM pages */
4761 for_each_zone(zone
) {
4762 if (!is_highmem(zone
))
4763 lowmem_pages
+= zone
->present_pages
;
4766 for_each_zone(zone
) {
4769 spin_lock_irqsave(&zone
->lock
, flags
);
4770 tmp
= (u64
)pages_min
* zone
->present_pages
;
4771 do_div(tmp
, lowmem_pages
);
4772 if (is_highmem(zone
)) {
4774 * __GFP_HIGH and PF_MEMALLOC allocations usually don't
4775 * need highmem pages, so cap pages_min to a small
4778 * The WMARK_HIGH-WMARK_LOW and (WMARK_LOW-WMARK_MIN)
4779 * deltas controls asynch page reclaim, and so should
4780 * not be capped for highmem.
4784 min_pages
= zone
->present_pages
/ 1024;
4785 if (min_pages
< SWAP_CLUSTER_MAX
)
4786 min_pages
= SWAP_CLUSTER_MAX
;
4787 if (min_pages
> 128)
4789 zone
->watermark
[WMARK_MIN
] = min_pages
;
4792 * If it's a lowmem zone, reserve a number of pages
4793 * proportionate to the zone's size.
4795 zone
->watermark
[WMARK_MIN
] = tmp
;
4798 zone
->watermark
[WMARK_LOW
] = min_wmark_pages(zone
) + (tmp
>> 2);
4799 zone
->watermark
[WMARK_HIGH
] = min_wmark_pages(zone
) + (tmp
>> 1);
4800 setup_zone_migrate_reserve(zone
);
4801 spin_unlock_irqrestore(&zone
->lock
, flags
);
4804 /* update totalreserve_pages */
4805 calculate_totalreserve_pages();
4809 * The inactive anon list should be small enough that the VM never has to
4810 * do too much work, but large enough that each inactive page has a chance
4811 * to be referenced again before it is swapped out.
4813 * The inactive_anon ratio is the target ratio of ACTIVE_ANON to
4814 * INACTIVE_ANON pages on this zone's LRU, maintained by the
4815 * pageout code. A zone->inactive_ratio of 3 means 3:1 or 25% of
4816 * the anonymous pages are kept on the inactive list.
4819 * memory ratio inactive anon
4820 * -------------------------------------
4829 void calculate_zone_inactive_ratio(struct zone
*zone
)
4831 unsigned int gb
, ratio
;
4833 /* Zone size in gigabytes */
4834 gb
= zone
->present_pages
>> (30 - PAGE_SHIFT
);
4836 ratio
= int_sqrt(10 * gb
);
4840 zone
->inactive_ratio
= ratio
;
4843 static void __init
setup_per_zone_inactive_ratio(void)
4848 calculate_zone_inactive_ratio(zone
);
4852 * Initialise min_free_kbytes.
4854 * For small machines we want it small (128k min). For large machines
4855 * we want it large (64MB max). But it is not linear, because network
4856 * bandwidth does not increase linearly with machine size. We use
4858 * min_free_kbytes = 4 * sqrt(lowmem_kbytes), for better accuracy:
4859 * min_free_kbytes = sqrt(lowmem_kbytes * 16)
4875 static int __init
init_per_zone_wmark_min(void)
4877 unsigned long lowmem_kbytes
;
4879 lowmem_kbytes
= nr_free_buffer_pages() * (PAGE_SIZE
>> 10);
4881 min_free_kbytes
= int_sqrt(lowmem_kbytes
* 16);
4882 if (min_free_kbytes
< 128)
4883 min_free_kbytes
= 128;
4884 if (min_free_kbytes
> 65536)
4885 min_free_kbytes
= 65536;
4886 setup_per_zone_wmarks();
4887 setup_per_zone_lowmem_reserve();
4888 setup_per_zone_inactive_ratio();
4891 module_init(init_per_zone_wmark_min
)
4894 * min_free_kbytes_sysctl_handler - just a wrapper around proc_dointvec() so
4895 * that we can call two helper functions whenever min_free_kbytes
4898 int min_free_kbytes_sysctl_handler(ctl_table
*table
, int write
,
4899 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
4901 proc_dointvec(table
, write
, buffer
, length
, ppos
);
4903 setup_per_zone_wmarks();
4908 int sysctl_min_unmapped_ratio_sysctl_handler(ctl_table
*table
, int write
,
4909 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
4914 rc
= proc_dointvec_minmax(table
, write
, buffer
, length
, ppos
);
4919 zone
->min_unmapped_pages
= (zone
->present_pages
*
4920 sysctl_min_unmapped_ratio
) / 100;
4924 int sysctl_min_slab_ratio_sysctl_handler(ctl_table
*table
, int write
,
4925 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
4930 rc
= proc_dointvec_minmax(table
, write
, buffer
, length
, ppos
);
4935 zone
->min_slab_pages
= (zone
->present_pages
*
4936 sysctl_min_slab_ratio
) / 100;
4942 * lowmem_reserve_ratio_sysctl_handler - just a wrapper around
4943 * proc_dointvec() so that we can call setup_per_zone_lowmem_reserve()
4944 * whenever sysctl_lowmem_reserve_ratio changes.
4946 * The reserve ratio obviously has absolutely no relation with the
4947 * minimum watermarks. The lowmem reserve ratio can only make sense
4948 * if in function of the boot time zone sizes.
4950 int lowmem_reserve_ratio_sysctl_handler(ctl_table
*table
, int write
,
4951 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
4953 proc_dointvec_minmax(table
, write
, buffer
, length
, ppos
);
4954 setup_per_zone_lowmem_reserve();
4959 * percpu_pagelist_fraction - changes the pcp->high for each zone on each
4960 * cpu. It is the fraction of total pages in each zone that a hot per cpu pagelist
4961 * can have before it gets flushed back to buddy allocator.
4964 int percpu_pagelist_fraction_sysctl_handler(ctl_table
*table
, int write
,
4965 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
4971 ret
= proc_dointvec_minmax(table
, write
, buffer
, length
, ppos
);
4972 if (!write
|| (ret
== -EINVAL
))
4974 for_each_populated_zone(zone
) {
4975 for_each_possible_cpu(cpu
) {
4977 high
= zone
->present_pages
/ percpu_pagelist_fraction
;
4978 setup_pagelist_highmark(
4979 per_cpu_ptr(zone
->pageset
, cpu
), high
);
4985 int hashdist
= HASHDIST_DEFAULT
;
4988 static int __init
set_hashdist(char *str
)
4992 hashdist
= simple_strtoul(str
, &str
, 0);
4995 __setup("hashdist=", set_hashdist
);
4999 * allocate a large system hash table from bootmem
5000 * - it is assumed that the hash table must contain an exact power-of-2
5001 * quantity of entries
5002 * - limit is the number of hash buckets, not the total allocation size
5004 void *__init
alloc_large_system_hash(const char *tablename
,
5005 unsigned long bucketsize
,
5006 unsigned long numentries
,
5009 unsigned int *_hash_shift
,
5010 unsigned int *_hash_mask
,
5011 unsigned long limit
)
5013 unsigned long long max
= limit
;
5014 unsigned long log2qty
, size
;
5017 /* allow the kernel cmdline to have a say */
5019 /* round applicable memory size up to nearest megabyte */
5020 numentries
= nr_kernel_pages
;
5021 numentries
+= (1UL << (20 - PAGE_SHIFT
)) - 1;
5022 numentries
>>= 20 - PAGE_SHIFT
;
5023 numentries
<<= 20 - PAGE_SHIFT
;
5025 /* limit to 1 bucket per 2^scale bytes of low memory */
5026 if (scale
> PAGE_SHIFT
)
5027 numentries
>>= (scale
- PAGE_SHIFT
);
5029 numentries
<<= (PAGE_SHIFT
- scale
);
5031 /* Make sure we've got at least a 0-order allocation.. */
5032 if (unlikely(flags
& HASH_SMALL
)) {
5033 /* Makes no sense without HASH_EARLY */
5034 WARN_ON(!(flags
& HASH_EARLY
));
5035 if (!(numentries
>> *_hash_shift
)) {
5036 numentries
= 1UL << *_hash_shift
;
5037 BUG_ON(!numentries
);
5039 } else if (unlikely((numentries
* bucketsize
) < PAGE_SIZE
))
5040 numentries
= PAGE_SIZE
/ bucketsize
;
5042 numentries
= roundup_pow_of_two(numentries
);
5044 /* limit allocation size to 1/16 total memory by default */
5046 max
= ((unsigned long long)nr_all_pages
<< PAGE_SHIFT
) >> 4;
5047 do_div(max
, bucketsize
);
5050 if (numentries
> max
)
5053 log2qty
= ilog2(numentries
);
5056 size
= bucketsize
<< log2qty
;
5057 if (flags
& HASH_EARLY
)
5058 table
= alloc_bootmem_nopanic(size
);
5060 table
= __vmalloc(size
, GFP_ATOMIC
, PAGE_KERNEL
);
5063 * If bucketsize is not a power-of-two, we may free
5064 * some pages at the end of hash table which
5065 * alloc_pages_exact() automatically does
5067 if (get_order(size
) < MAX_ORDER
) {
5068 table
= alloc_pages_exact(size
, GFP_ATOMIC
);
5069 kmemleak_alloc(table
, size
, 1, GFP_ATOMIC
);
5072 } while (!table
&& size
> PAGE_SIZE
&& --log2qty
);
5075 panic("Failed to allocate %s hash table\n", tablename
);
5077 printk(KERN_INFO
"%s hash table entries: %d (order: %d, %lu bytes)\n",
5080 ilog2(size
) - PAGE_SHIFT
,
5084 *_hash_shift
= log2qty
;
5086 *_hash_mask
= (1 << log2qty
) - 1;
5091 /* Return a pointer to the bitmap storing bits affecting a block of pages */
5092 static inline unsigned long *get_pageblock_bitmap(struct zone
*zone
,
5095 #ifdef CONFIG_SPARSEMEM
5096 return __pfn_to_section(pfn
)->pageblock_flags
;
5098 return zone
->pageblock_flags
;
5099 #endif /* CONFIG_SPARSEMEM */
5102 static inline int pfn_to_bitidx(struct zone
*zone
, unsigned long pfn
)
5104 #ifdef CONFIG_SPARSEMEM
5105 pfn
&= (PAGES_PER_SECTION
-1);
5106 return (pfn
>> pageblock_order
) * NR_PAGEBLOCK_BITS
;
5108 pfn
= pfn
- zone
->zone_start_pfn
;
5109 return (pfn
>> pageblock_order
) * NR_PAGEBLOCK_BITS
;
5110 #endif /* CONFIG_SPARSEMEM */
5114 * get_pageblock_flags_group - Return the requested group of flags for the pageblock_nr_pages block of pages
5115 * @page: The page within the block of interest
5116 * @start_bitidx: The first bit of interest to retrieve
5117 * @end_bitidx: The last bit of interest
5118 * returns pageblock_bits flags
5120 unsigned long get_pageblock_flags_group(struct page
*page
,
5121 int start_bitidx
, int end_bitidx
)
5124 unsigned long *bitmap
;
5125 unsigned long pfn
, bitidx
;
5126 unsigned long flags
= 0;
5127 unsigned long value
= 1;
5129 zone
= page_zone(page
);
5130 pfn
= page_to_pfn(page
);
5131 bitmap
= get_pageblock_bitmap(zone
, pfn
);
5132 bitidx
= pfn_to_bitidx(zone
, pfn
);
5134 for (; start_bitidx
<= end_bitidx
; start_bitidx
++, value
<<= 1)
5135 if (test_bit(bitidx
+ start_bitidx
, bitmap
))
5142 * set_pageblock_flags_group - Set the requested group of flags for a pageblock_nr_pages block of pages
5143 * @page: The page within the block of interest
5144 * @start_bitidx: The first bit of interest
5145 * @end_bitidx: The last bit of interest
5146 * @flags: The flags to set
5148 void set_pageblock_flags_group(struct page
*page
, unsigned long flags
,
5149 int start_bitidx
, int end_bitidx
)
5152 unsigned long *bitmap
;
5153 unsigned long pfn
, bitidx
;
5154 unsigned long value
= 1;
5156 zone
= page_zone(page
);
5157 pfn
= page_to_pfn(page
);
5158 bitmap
= get_pageblock_bitmap(zone
, pfn
);
5159 bitidx
= pfn_to_bitidx(zone
, pfn
);
5160 VM_BUG_ON(pfn
< zone
->zone_start_pfn
);
5161 VM_BUG_ON(pfn
>= zone
->zone_start_pfn
+ zone
->spanned_pages
);
5163 for (; start_bitidx
<= end_bitidx
; start_bitidx
++, value
<<= 1)
5165 __set_bit(bitidx
+ start_bitidx
, bitmap
);
5167 __clear_bit(bitidx
+ start_bitidx
, bitmap
);
5171 * This is designed as sub function...plz see page_isolation.c also.
5172 * set/clear page block's type to be ISOLATE.
5173 * page allocater never alloc memory from ISOLATE block.
5176 int set_migratetype_isolate(struct page
*page
)
5179 struct page
*curr_page
;
5180 unsigned long flags
, pfn
, iter
;
5181 unsigned long immobile
= 0;
5182 struct memory_isolate_notify arg
;
5187 zone
= page_zone(page
);
5188 zone_idx
= zone_idx(zone
);
5190 spin_lock_irqsave(&zone
->lock
, flags
);
5191 if (get_pageblock_migratetype(page
) == MIGRATE_MOVABLE
||
5192 zone_idx
== ZONE_MOVABLE
) {
5197 pfn
= page_to_pfn(page
);
5198 arg
.start_pfn
= pfn
;
5199 arg
.nr_pages
= pageblock_nr_pages
;
5200 arg
.pages_found
= 0;
5203 * It may be possible to isolate a pageblock even if the
5204 * migratetype is not MIGRATE_MOVABLE. The memory isolation
5205 * notifier chain is used by balloon drivers to return the
5206 * number of pages in a range that are held by the balloon
5207 * driver to shrink memory. If all the pages are accounted for
5208 * by balloons, are free, or on the LRU, isolation can continue.
5209 * Later, for example, when memory hotplug notifier runs, these
5210 * pages reported as "can be isolated" should be isolated(freed)
5211 * by the balloon driver through the memory notifier chain.
5213 notifier_ret
= memory_isolate_notify(MEM_ISOLATE_COUNT
, &arg
);
5214 notifier_ret
= notifier_to_errno(notifier_ret
);
5215 if (notifier_ret
|| !arg
.pages_found
)
5218 for (iter
= pfn
; iter
< (pfn
+ pageblock_nr_pages
); iter
++) {
5219 if (!pfn_valid_within(pfn
))
5222 curr_page
= pfn_to_page(iter
);
5223 if (!page_count(curr_page
) || PageLRU(curr_page
))
5229 if (arg
.pages_found
== immobile
)
5234 set_pageblock_migratetype(page
, MIGRATE_ISOLATE
);
5235 move_freepages_block(zone
, page
, MIGRATE_ISOLATE
);
5238 spin_unlock_irqrestore(&zone
->lock
, flags
);
5244 void unset_migratetype_isolate(struct page
*page
)
5247 unsigned long flags
;
5248 zone
= page_zone(page
);
5249 spin_lock_irqsave(&zone
->lock
, flags
);
5250 if (get_pageblock_migratetype(page
) != MIGRATE_ISOLATE
)
5252 set_pageblock_migratetype(page
, MIGRATE_MOVABLE
);
5253 move_freepages_block(zone
, page
, MIGRATE_MOVABLE
);
5255 spin_unlock_irqrestore(&zone
->lock
, flags
);
5258 #ifdef CONFIG_MEMORY_HOTREMOVE
5260 * All pages in the range must be isolated before calling this.
5263 __offline_isolated_pages(unsigned long start_pfn
, unsigned long end_pfn
)
5269 unsigned long flags
;
5270 /* find the first valid pfn */
5271 for (pfn
= start_pfn
; pfn
< end_pfn
; pfn
++)
5276 zone
= page_zone(pfn_to_page(pfn
));
5277 spin_lock_irqsave(&zone
->lock
, flags
);
5279 while (pfn
< end_pfn
) {
5280 if (!pfn_valid(pfn
)) {
5284 page
= pfn_to_page(pfn
);
5285 BUG_ON(page_count(page
));
5286 BUG_ON(!PageBuddy(page
));
5287 order
= page_order(page
);
5288 #ifdef CONFIG_DEBUG_VM
5289 printk(KERN_INFO
"remove from free list %lx %d %lx\n",
5290 pfn
, 1 << order
, end_pfn
);
5292 list_del(&page
->lru
);
5293 rmv_page_order(page
);
5294 zone
->free_area
[order
].nr_free
--;
5295 __mod_zone_page_state(zone
, NR_FREE_PAGES
,
5297 for (i
= 0; i
< (1 << order
); i
++)
5298 SetPageReserved((page
+i
));
5299 pfn
+= (1 << order
);
5301 spin_unlock_irqrestore(&zone
->lock
, flags
);
5305 #ifdef CONFIG_MEMORY_FAILURE
5306 bool is_free_buddy_page(struct page
*page
)
5308 struct zone
*zone
= page_zone(page
);
5309 unsigned long pfn
= page_to_pfn(page
);
5310 unsigned long flags
;
5313 spin_lock_irqsave(&zone
->lock
, flags
);
5314 for (order
= 0; order
< MAX_ORDER
; order
++) {
5315 struct page
*page_head
= page
- (pfn
& ((1 << order
) - 1));
5317 if (PageBuddy(page_head
) && page_order(page_head
) >= order
)
5320 spin_unlock_irqrestore(&zone
->lock
, flags
);
5322 return order
< MAX_ORDER
;
5326 static struct trace_print_flags pageflag_names
[] = {
5327 {1UL << PG_locked
, "locked" },
5328 {1UL << PG_error
, "error" },
5329 {1UL << PG_referenced
, "referenced" },
5330 {1UL << PG_uptodate
, "uptodate" },
5331 {1UL << PG_dirty
, "dirty" },
5332 {1UL << PG_lru
, "lru" },
5333 {1UL << PG_active
, "active" },
5334 {1UL << PG_slab
, "slab" },
5335 {1UL << PG_owner_priv_1
, "owner_priv_1" },
5336 {1UL << PG_arch_1
, "arch_1" },
5337 {1UL << PG_reserved
, "reserved" },
5338 {1UL << PG_private
, "private" },
5339 {1UL << PG_private_2
, "private_2" },
5340 {1UL << PG_writeback
, "writeback" },
5341 #ifdef CONFIG_PAGEFLAGS_EXTENDED
5342 {1UL << PG_head
, "head" },
5343 {1UL << PG_tail
, "tail" },
5345 {1UL << PG_compound
, "compound" },
5347 {1UL << PG_swapcache
, "swapcache" },
5348 {1UL << PG_mappedtodisk
, "mappedtodisk" },
5349 {1UL << PG_reclaim
, "reclaim" },
5350 {1UL << PG_buddy
, "buddy" },
5351 {1UL << PG_swapbacked
, "swapbacked" },
5352 {1UL << PG_unevictable
, "unevictable" },
5354 {1UL << PG_mlocked
, "mlocked" },
5356 #ifdef CONFIG_ARCH_USES_PG_UNCACHED
5357 {1UL << PG_uncached
, "uncached" },
5359 #ifdef CONFIG_MEMORY_FAILURE
5360 {1UL << PG_hwpoison
, "hwpoison" },
5365 static void dump_page_flags(unsigned long flags
)
5367 const char *delim
= "";
5371 printk(KERN_ALERT
"page flags: %#lx(", flags
);
5373 /* remove zone id */
5374 flags
&= (1UL << NR_PAGEFLAGS
) - 1;
5376 for (i
= 0; pageflag_names
[i
].name
&& flags
; i
++) {
5378 mask
= pageflag_names
[i
].mask
;
5379 if ((flags
& mask
) != mask
)
5383 printk("%s%s", delim
, pageflag_names
[i
].name
);
5387 /* check for left over flags */
5389 printk("%s%#lx", delim
, flags
);
5394 void dump_page(struct page
*page
)
5397 "page:%p count:%d mapcount:%d mapping:%p index:%#lx\n",
5398 page
, page_count(page
), page_mapcount(page
),
5399 page
->mapping
, page
->index
);
5400 dump_page_flags(page
->flags
);