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 <trace/events/kmem.h>
54 #include <asm/tlbflush.h>
55 #include <asm/div64.h>
59 * Array of node states.
61 nodemask_t node_states
[NR_NODE_STATES
] __read_mostly
= {
62 [N_POSSIBLE
] = NODE_MASK_ALL
,
63 [N_ONLINE
] = { { [0] = 1UL } },
65 [N_NORMAL_MEMORY
] = { { [0] = 1UL } },
67 [N_HIGH_MEMORY
] = { { [0] = 1UL } },
69 [N_CPU
] = { { [0] = 1UL } },
72 EXPORT_SYMBOL(node_states
);
74 unsigned long totalram_pages __read_mostly
;
75 unsigned long totalreserve_pages __read_mostly
;
76 int percpu_pagelist_fraction
;
77 gfp_t gfp_allowed_mask __read_mostly
= GFP_BOOT_MASK
;
79 #ifdef CONFIG_PM_SLEEP
81 * The following functions are used by the suspend/hibernate code to temporarily
82 * change gfp_allowed_mask in order to avoid using I/O during memory allocations
83 * while devices are suspended. To avoid races with the suspend/hibernate code,
84 * they should always be called with pm_mutex held (gfp_allowed_mask also should
85 * only be modified with pm_mutex held, unless the suspend/hibernate code is
86 * guaranteed not to run in parallel with that modification).
88 void set_gfp_allowed_mask(gfp_t mask
)
90 WARN_ON(!mutex_is_locked(&pm_mutex
));
91 gfp_allowed_mask
= mask
;
94 gfp_t
clear_gfp_allowed_mask(gfp_t mask
)
96 gfp_t ret
= gfp_allowed_mask
;
98 WARN_ON(!mutex_is_locked(&pm_mutex
));
99 gfp_allowed_mask
&= ~mask
;
102 #endif /* CONFIG_PM_SLEEP */
104 #ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
105 int pageblock_order __read_mostly
;
108 static void __free_pages_ok(struct page
*page
, unsigned int order
);
111 * results with 256, 32 in the lowmem_reserve sysctl:
112 * 1G machine -> (16M dma, 800M-16M normal, 1G-800M high)
113 * 1G machine -> (16M dma, 784M normal, 224M high)
114 * NORMAL allocation will leave 784M/256 of ram reserved in the ZONE_DMA
115 * HIGHMEM allocation will leave 224M/32 of ram reserved in ZONE_NORMAL
116 * HIGHMEM allocation will (224M+784M)/256 of ram reserved in ZONE_DMA
118 * TBD: should special case ZONE_DMA32 machines here - in those we normally
119 * don't need any ZONE_NORMAL reservation
121 int sysctl_lowmem_reserve_ratio
[MAX_NR_ZONES
-1] = {
122 #ifdef CONFIG_ZONE_DMA
125 #ifdef CONFIG_ZONE_DMA32
128 #ifdef CONFIG_HIGHMEM
134 EXPORT_SYMBOL(totalram_pages
);
136 static char * const zone_names
[MAX_NR_ZONES
] = {
137 #ifdef CONFIG_ZONE_DMA
140 #ifdef CONFIG_ZONE_DMA32
144 #ifdef CONFIG_HIGHMEM
150 int min_free_kbytes
= 1024;
152 static unsigned long __meminitdata nr_kernel_pages
;
153 static unsigned long __meminitdata nr_all_pages
;
154 static unsigned long __meminitdata dma_reserve
;
156 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
158 * MAX_ACTIVE_REGIONS determines the maximum number of distinct
159 * ranges of memory (RAM) that may be registered with add_active_range().
160 * Ranges passed to add_active_range() will be merged if possible
161 * so the number of times add_active_range() can be called is
162 * related to the number of nodes and the number of holes
164 #ifdef CONFIG_MAX_ACTIVE_REGIONS
165 /* Allow an architecture to set MAX_ACTIVE_REGIONS to save memory */
166 #define MAX_ACTIVE_REGIONS CONFIG_MAX_ACTIVE_REGIONS
168 #if MAX_NUMNODES >= 32
169 /* If there can be many nodes, allow up to 50 holes per node */
170 #define MAX_ACTIVE_REGIONS (MAX_NUMNODES*50)
172 /* By default, allow up to 256 distinct regions */
173 #define MAX_ACTIVE_REGIONS 256
177 static struct node_active_region __meminitdata early_node_map
[MAX_ACTIVE_REGIONS
];
178 static int __meminitdata nr_nodemap_entries
;
179 static unsigned long __meminitdata arch_zone_lowest_possible_pfn
[MAX_NR_ZONES
];
180 static unsigned long __meminitdata arch_zone_highest_possible_pfn
[MAX_NR_ZONES
];
181 static unsigned long __initdata required_kernelcore
;
182 static unsigned long __initdata required_movablecore
;
183 static unsigned long __meminitdata zone_movable_pfn
[MAX_NUMNODES
];
185 /* movable_zone is the "real" zone pages in ZONE_MOVABLE are taken from */
187 EXPORT_SYMBOL(movable_zone
);
188 #endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
191 int nr_node_ids __read_mostly
= MAX_NUMNODES
;
192 int nr_online_nodes __read_mostly
= 1;
193 EXPORT_SYMBOL(nr_node_ids
);
194 EXPORT_SYMBOL(nr_online_nodes
);
197 int page_group_by_mobility_disabled __read_mostly
;
199 static void set_pageblock_migratetype(struct page
*page
, int migratetype
)
202 if (unlikely(page_group_by_mobility_disabled
))
203 migratetype
= MIGRATE_UNMOVABLE
;
205 set_pageblock_flags_group(page
, (unsigned long)migratetype
,
206 PB_migrate
, PB_migrate_end
);
209 bool oom_killer_disabled __read_mostly
;
211 #ifdef CONFIG_DEBUG_VM
212 static int page_outside_zone_boundaries(struct zone
*zone
, struct page
*page
)
216 unsigned long pfn
= page_to_pfn(page
);
219 seq
= zone_span_seqbegin(zone
);
220 if (pfn
>= zone
->zone_start_pfn
+ zone
->spanned_pages
)
222 else if (pfn
< zone
->zone_start_pfn
)
224 } while (zone_span_seqretry(zone
, seq
));
229 static int page_is_consistent(struct zone
*zone
, struct page
*page
)
231 if (!pfn_valid_within(page_to_pfn(page
)))
233 if (zone
!= page_zone(page
))
239 * Temporary debugging check for pages not lying within a given zone.
241 static int bad_range(struct zone
*zone
, struct page
*page
)
243 if (page_outside_zone_boundaries(zone
, page
))
245 if (!page_is_consistent(zone
, page
))
251 static inline int bad_range(struct zone
*zone
, struct page
*page
)
257 static void bad_page(struct page
*page
)
259 static unsigned long resume
;
260 static unsigned long nr_shown
;
261 static unsigned long nr_unshown
;
263 /* Don't complain about poisoned pages */
264 if (PageHWPoison(page
)) {
265 __ClearPageBuddy(page
);
270 * Allow a burst of 60 reports, then keep quiet for that minute;
271 * or allow a steady drip of one report per second.
273 if (nr_shown
== 60) {
274 if (time_before(jiffies
, resume
)) {
280 "BUG: Bad page state: %lu messages suppressed\n",
287 resume
= jiffies
+ 60 * HZ
;
289 printk(KERN_ALERT
"BUG: Bad page state in process %s pfn:%05lx\n",
290 current
->comm
, page_to_pfn(page
));
292 "page:%p flags:%p count:%d mapcount:%d mapping:%p index:%lx\n",
293 page
, (void *)page
->flags
, page_count(page
),
294 page_mapcount(page
), page
->mapping
, page
->index
);
298 /* Leave bad fields for debug, except PageBuddy could make trouble */
299 __ClearPageBuddy(page
);
300 add_taint(TAINT_BAD_PAGE
);
304 * Higher-order pages are called "compound pages". They are structured thusly:
306 * The first PAGE_SIZE page is called the "head page".
308 * The remaining PAGE_SIZE pages are called "tail pages".
310 * All pages have PG_compound set. All pages have their ->private pointing at
311 * the head page (even the head page has this).
313 * The first tail page's ->lru.next holds the address of the compound page's
314 * put_page() function. Its ->lru.prev holds the order of allocation.
315 * This usage means that zero-order pages may not be compound.
318 static void free_compound_page(struct page
*page
)
320 __free_pages_ok(page
, compound_order(page
));
323 void prep_compound_page(struct page
*page
, unsigned long order
)
326 int nr_pages
= 1 << order
;
328 set_compound_page_dtor(page
, free_compound_page
);
329 set_compound_order(page
, order
);
331 for (i
= 1; i
< nr_pages
; i
++) {
332 struct page
*p
= page
+ i
;
335 p
->first_page
= page
;
339 static int destroy_compound_page(struct page
*page
, unsigned long order
)
342 int nr_pages
= 1 << order
;
345 if (unlikely(compound_order(page
) != order
) ||
346 unlikely(!PageHead(page
))) {
351 __ClearPageHead(page
);
353 for (i
= 1; i
< nr_pages
; i
++) {
354 struct page
*p
= page
+ i
;
356 if (unlikely(!PageTail(p
) || (p
->first_page
!= page
))) {
366 static inline void prep_zero_page(struct page
*page
, int order
, gfp_t gfp_flags
)
371 * clear_highpage() will use KM_USER0, so it's a bug to use __GFP_ZERO
372 * and __GFP_HIGHMEM from hard or soft interrupt context.
374 VM_BUG_ON((gfp_flags
& __GFP_HIGHMEM
) && in_interrupt());
375 for (i
= 0; i
< (1 << order
); i
++)
376 clear_highpage(page
+ i
);
379 static inline void set_page_order(struct page
*page
, int order
)
381 set_page_private(page
, order
);
382 __SetPageBuddy(page
);
385 static inline void rmv_page_order(struct page
*page
)
387 __ClearPageBuddy(page
);
388 set_page_private(page
, 0);
392 * Locate the struct page for both the matching buddy in our
393 * pair (buddy1) and the combined O(n+1) page they form (page).
395 * 1) Any buddy B1 will have an order O twin B2 which satisfies
396 * the following equation:
398 * For example, if the starting buddy (buddy2) is #8 its order
400 * B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10
402 * 2) Any buddy B will have an order O+1 parent P which
403 * satisfies the following equation:
406 * Assumption: *_mem_map is contiguous at least up to MAX_ORDER
408 static inline struct page
*
409 __page_find_buddy(struct page
*page
, unsigned long page_idx
, unsigned int order
)
411 unsigned long buddy_idx
= page_idx
^ (1 << order
);
413 return page
+ (buddy_idx
- page_idx
);
416 static inline unsigned long
417 __find_combined_index(unsigned long page_idx
, unsigned int order
)
419 return (page_idx
& ~(1 << order
));
423 * This function checks whether a page is free && is the buddy
424 * we can do coalesce a page and its buddy if
425 * (a) the buddy is not in a hole &&
426 * (b) the buddy is in the buddy system &&
427 * (c) a page and its buddy have the same order &&
428 * (d) a page and its buddy are in the same zone.
430 * For recording whether a page is in the buddy system, we use PG_buddy.
431 * Setting, clearing, and testing PG_buddy is serialized by zone->lock.
433 * For recording page's order, we use page_private(page).
435 static inline int page_is_buddy(struct page
*page
, struct page
*buddy
,
438 if (!pfn_valid_within(page_to_pfn(buddy
)))
441 if (page_zone_id(page
) != page_zone_id(buddy
))
444 if (PageBuddy(buddy
) && page_order(buddy
) == order
) {
445 VM_BUG_ON(page_count(buddy
) != 0);
452 * Freeing function for a buddy system allocator.
454 * The concept of a buddy system is to maintain direct-mapped table
455 * (containing bit values) for memory blocks of various "orders".
456 * The bottom level table contains the map for the smallest allocatable
457 * units of memory (here, pages), and each level above it describes
458 * pairs of units from the levels below, hence, "buddies".
459 * At a high level, all that happens here is marking the table entry
460 * at the bottom level available, and propagating the changes upward
461 * as necessary, plus some accounting needed to play nicely with other
462 * parts of the VM system.
463 * At each level, we keep a list of pages, which are heads of continuous
464 * free pages of length of (1 << order) and marked with PG_buddy. Page's
465 * order is recorded in page_private(page) field.
466 * So when we are allocating or freeing one, we can derive the state of the
467 * other. That is, if we allocate a small block, and both were
468 * free, the remainder of the region must be split into blocks.
469 * If a block is freed, and its buddy is also free, then this
470 * triggers coalescing into a block of larger size.
475 static inline void __free_one_page(struct page
*page
,
476 struct zone
*zone
, unsigned int order
,
479 unsigned long page_idx
;
481 if (unlikely(PageCompound(page
)))
482 if (unlikely(destroy_compound_page(page
, order
)))
485 VM_BUG_ON(migratetype
== -1);
487 page_idx
= page_to_pfn(page
) & ((1 << MAX_ORDER
) - 1);
489 VM_BUG_ON(page_idx
& ((1 << order
) - 1));
490 VM_BUG_ON(bad_range(zone
, page
));
492 while (order
< MAX_ORDER
-1) {
493 unsigned long combined_idx
;
496 buddy
= __page_find_buddy(page
, page_idx
, order
);
497 if (!page_is_buddy(page
, buddy
, order
))
500 /* Our buddy is free, merge with it and move up one order. */
501 list_del(&buddy
->lru
);
502 zone
->free_area
[order
].nr_free
--;
503 rmv_page_order(buddy
);
504 combined_idx
= __find_combined_index(page_idx
, order
);
505 page
= page
+ (combined_idx
- page_idx
);
506 page_idx
= combined_idx
;
509 set_page_order(page
, order
);
511 &zone
->free_area
[order
].free_list
[migratetype
]);
512 zone
->free_area
[order
].nr_free
++;
516 * free_page_mlock() -- clean up attempts to free and mlocked() page.
517 * Page should not be on lru, so no need to fix that up.
518 * free_pages_check() will verify...
520 static inline void free_page_mlock(struct page
*page
)
522 __dec_zone_page_state(page
, NR_MLOCK
);
523 __count_vm_event(UNEVICTABLE_MLOCKFREED
);
526 static inline int free_pages_check(struct page
*page
)
528 if (unlikely(page_mapcount(page
) |
529 (page
->mapping
!= NULL
) |
530 (atomic_read(&page
->_count
) != 0) |
531 (page
->flags
& PAGE_FLAGS_CHECK_AT_FREE
))) {
535 if (page
->flags
& PAGE_FLAGS_CHECK_AT_PREP
)
536 page
->flags
&= ~PAGE_FLAGS_CHECK_AT_PREP
;
541 * Frees a number of pages from the PCP lists
542 * Assumes all pages on list are in same zone, and of same order.
543 * count is the number of pages to free.
545 * If the zone was previously in an "all pages pinned" state then look to
546 * see if this freeing clears that state.
548 * And clear the zone's pages_scanned counter, to hold off the "all pages are
549 * pinned" detection logic.
551 static void free_pcppages_bulk(struct zone
*zone
, int count
,
552 struct per_cpu_pages
*pcp
)
557 spin_lock(&zone
->lock
);
558 zone
->all_unreclaimable
= 0;
559 zone
->pages_scanned
= 0;
561 __mod_zone_page_state(zone
, NR_FREE_PAGES
, count
);
564 struct list_head
*list
;
567 * Remove pages from lists in a round-robin fashion. A
568 * batch_free count is maintained that is incremented when an
569 * empty list is encountered. This is so more pages are freed
570 * off fuller lists instead of spinning excessively around empty
575 if (++migratetype
== MIGRATE_PCPTYPES
)
577 list
= &pcp
->lists
[migratetype
];
578 } while (list_empty(list
));
581 page
= list_entry(list
->prev
, struct page
, lru
);
582 /* must delete as __free_one_page list manipulates */
583 list_del(&page
->lru
);
584 /* MIGRATE_MOVABLE list may include MIGRATE_RESERVEs */
585 __free_one_page(page
, zone
, 0, page_private(page
));
586 trace_mm_page_pcpu_drain(page
, 0, page_private(page
));
587 } while (--count
&& --batch_free
&& !list_empty(list
));
589 spin_unlock(&zone
->lock
);
592 static void free_one_page(struct zone
*zone
, struct page
*page
, int order
,
595 spin_lock(&zone
->lock
);
596 zone
->all_unreclaimable
= 0;
597 zone
->pages_scanned
= 0;
599 __mod_zone_page_state(zone
, NR_FREE_PAGES
, 1 << order
);
600 __free_one_page(page
, zone
, order
, migratetype
);
601 spin_unlock(&zone
->lock
);
604 static void __free_pages_ok(struct page
*page
, unsigned int order
)
609 int wasMlocked
= __TestClearPageMlocked(page
);
611 trace_mm_page_free_direct(page
, order
);
612 kmemcheck_free_shadow(page
, order
);
614 for (i
= 0 ; i
< (1 << order
) ; ++i
)
615 bad
+= free_pages_check(page
+ i
);
619 if (!PageHighMem(page
)) {
620 debug_check_no_locks_freed(page_address(page
),PAGE_SIZE
<<order
);
621 debug_check_no_obj_freed(page_address(page
),
624 arch_free_page(page
, order
);
625 kernel_map_pages(page
, 1 << order
, 0);
627 local_irq_save(flags
);
628 if (unlikely(wasMlocked
))
629 free_page_mlock(page
);
630 __count_vm_events(PGFREE
, 1 << order
);
631 free_one_page(page_zone(page
), page
, order
,
632 get_pageblock_migratetype(page
));
633 local_irq_restore(flags
);
637 * permit the bootmem allocator to evade page validation on high-order frees
639 void __meminit
__free_pages_bootmem(struct page
*page
, unsigned int order
)
642 __ClearPageReserved(page
);
643 set_page_count(page
, 0);
644 set_page_refcounted(page
);
650 for (loop
= 0; loop
< BITS_PER_LONG
; loop
++) {
651 struct page
*p
= &page
[loop
];
653 if (loop
+ 1 < BITS_PER_LONG
)
655 __ClearPageReserved(p
);
656 set_page_count(p
, 0);
659 set_page_refcounted(page
);
660 __free_pages(page
, order
);
666 * The order of subdivision here is critical for the IO subsystem.
667 * Please do not alter this order without good reasons and regression
668 * testing. Specifically, as large blocks of memory are subdivided,
669 * the order in which smaller blocks are delivered depends on the order
670 * they're subdivided in this function. This is the primary factor
671 * influencing the order in which pages are delivered to the IO
672 * subsystem according to empirical testing, and this is also justified
673 * by considering the behavior of a buddy system containing a single
674 * large block of memory acted on by a series of small allocations.
675 * This behavior is a critical factor in sglist merging's success.
679 static inline void expand(struct zone
*zone
, struct page
*page
,
680 int low
, int high
, struct free_area
*area
,
683 unsigned long size
= 1 << high
;
689 VM_BUG_ON(bad_range(zone
, &page
[size
]));
690 list_add(&page
[size
].lru
, &area
->free_list
[migratetype
]);
692 set_page_order(&page
[size
], high
);
697 * This page is about to be returned from the page allocator
699 static inline int check_new_page(struct page
*page
)
701 if (unlikely(page_mapcount(page
) |
702 (page
->mapping
!= NULL
) |
703 (atomic_read(&page
->_count
) != 0) |
704 (page
->flags
& PAGE_FLAGS_CHECK_AT_PREP
))) {
711 static int prep_new_page(struct page
*page
, int order
, gfp_t gfp_flags
)
715 for (i
= 0; i
< (1 << order
); i
++) {
716 struct page
*p
= page
+ i
;
717 if (unlikely(check_new_page(p
)))
721 set_page_private(page
, 0);
722 set_page_refcounted(page
);
724 arch_alloc_page(page
, order
);
725 kernel_map_pages(page
, 1 << order
, 1);
727 if (gfp_flags
& __GFP_ZERO
)
728 prep_zero_page(page
, order
, gfp_flags
);
730 if (order
&& (gfp_flags
& __GFP_COMP
))
731 prep_compound_page(page
, order
);
737 * Go through the free lists for the given migratetype and remove
738 * the smallest available page from the freelists
741 struct page
*__rmqueue_smallest(struct zone
*zone
, unsigned int order
,
744 unsigned int current_order
;
745 struct free_area
* area
;
748 /* Find a page of the appropriate size in the preferred list */
749 for (current_order
= order
; current_order
< MAX_ORDER
; ++current_order
) {
750 area
= &(zone
->free_area
[current_order
]);
751 if (list_empty(&area
->free_list
[migratetype
]))
754 page
= list_entry(area
->free_list
[migratetype
].next
,
756 list_del(&page
->lru
);
757 rmv_page_order(page
);
759 expand(zone
, page
, order
, current_order
, area
, migratetype
);
768 * This array describes the order lists are fallen back to when
769 * the free lists for the desirable migrate type are depleted
771 static int fallbacks
[MIGRATE_TYPES
][MIGRATE_TYPES
-1] = {
772 [MIGRATE_UNMOVABLE
] = { MIGRATE_RECLAIMABLE
, MIGRATE_MOVABLE
, MIGRATE_RESERVE
},
773 [MIGRATE_RECLAIMABLE
] = { MIGRATE_UNMOVABLE
, MIGRATE_MOVABLE
, MIGRATE_RESERVE
},
774 [MIGRATE_MOVABLE
] = { MIGRATE_RECLAIMABLE
, MIGRATE_UNMOVABLE
, MIGRATE_RESERVE
},
775 [MIGRATE_RESERVE
] = { MIGRATE_RESERVE
, MIGRATE_RESERVE
, MIGRATE_RESERVE
}, /* Never used */
779 * Move the free pages in a range to the free lists of the requested type.
780 * Note that start_page and end_pages are not aligned on a pageblock
781 * boundary. If alignment is required, use move_freepages_block()
783 static int move_freepages(struct zone
*zone
,
784 struct page
*start_page
, struct page
*end_page
,
791 #ifndef CONFIG_HOLES_IN_ZONE
793 * page_zone is not safe to call in this context when
794 * CONFIG_HOLES_IN_ZONE is set. This bug check is probably redundant
795 * anyway as we check zone boundaries in move_freepages_block().
796 * Remove at a later date when no bug reports exist related to
797 * grouping pages by mobility
799 BUG_ON(page_zone(start_page
) != page_zone(end_page
));
802 for (page
= start_page
; page
<= end_page
;) {
803 /* Make sure we are not inadvertently changing nodes */
804 VM_BUG_ON(page_to_nid(page
) != zone_to_nid(zone
));
806 if (!pfn_valid_within(page_to_pfn(page
))) {
811 if (!PageBuddy(page
)) {
816 order
= page_order(page
);
817 list_del(&page
->lru
);
819 &zone
->free_area
[order
].free_list
[migratetype
]);
821 pages_moved
+= 1 << order
;
827 static int move_freepages_block(struct zone
*zone
, struct page
*page
,
830 unsigned long start_pfn
, end_pfn
;
831 struct page
*start_page
, *end_page
;
833 start_pfn
= page_to_pfn(page
);
834 start_pfn
= start_pfn
& ~(pageblock_nr_pages
-1);
835 start_page
= pfn_to_page(start_pfn
);
836 end_page
= start_page
+ pageblock_nr_pages
- 1;
837 end_pfn
= start_pfn
+ pageblock_nr_pages
- 1;
839 /* Do not cross zone boundaries */
840 if (start_pfn
< zone
->zone_start_pfn
)
842 if (end_pfn
>= zone
->zone_start_pfn
+ zone
->spanned_pages
)
845 return move_freepages(zone
, start_page
, end_page
, migratetype
);
848 static void change_pageblock_range(struct page
*pageblock_page
,
849 int start_order
, int migratetype
)
851 int nr_pageblocks
= 1 << (start_order
- pageblock_order
);
853 while (nr_pageblocks
--) {
854 set_pageblock_migratetype(pageblock_page
, migratetype
);
855 pageblock_page
+= pageblock_nr_pages
;
859 /* Remove an element from the buddy allocator from the fallback list */
860 static inline struct page
*
861 __rmqueue_fallback(struct zone
*zone
, int order
, int start_migratetype
)
863 struct free_area
* area
;
868 /* Find the largest possible block of pages in the other list */
869 for (current_order
= MAX_ORDER
-1; current_order
>= order
;
871 for (i
= 0; i
< MIGRATE_TYPES
- 1; i
++) {
872 migratetype
= fallbacks
[start_migratetype
][i
];
874 /* MIGRATE_RESERVE handled later if necessary */
875 if (migratetype
== MIGRATE_RESERVE
)
878 area
= &(zone
->free_area
[current_order
]);
879 if (list_empty(&area
->free_list
[migratetype
]))
882 page
= list_entry(area
->free_list
[migratetype
].next
,
887 * If breaking a large block of pages, move all free
888 * pages to the preferred allocation list. If falling
889 * back for a reclaimable kernel allocation, be more
890 * agressive about taking ownership of free pages
892 if (unlikely(current_order
>= (pageblock_order
>> 1)) ||
893 start_migratetype
== MIGRATE_RECLAIMABLE
||
894 page_group_by_mobility_disabled
) {
896 pages
= move_freepages_block(zone
, page
,
899 /* Claim the whole block if over half of it is free */
900 if (pages
>= (1 << (pageblock_order
-1)) ||
901 page_group_by_mobility_disabled
)
902 set_pageblock_migratetype(page
,
905 migratetype
= start_migratetype
;
908 /* Remove the page from the freelists */
909 list_del(&page
->lru
);
910 rmv_page_order(page
);
912 /* Take ownership for orders >= pageblock_order */
913 if (current_order
>= pageblock_order
)
914 change_pageblock_range(page
, current_order
,
917 expand(zone
, page
, order
, current_order
, area
, migratetype
);
919 trace_mm_page_alloc_extfrag(page
, order
, current_order
,
920 start_migratetype
, migratetype
);
930 * Do the hard work of removing an element from the buddy allocator.
931 * Call me with the zone->lock already held.
933 static struct page
*__rmqueue(struct zone
*zone
, unsigned int order
,
939 page
= __rmqueue_smallest(zone
, order
, migratetype
);
941 if (unlikely(!page
) && migratetype
!= MIGRATE_RESERVE
) {
942 page
= __rmqueue_fallback(zone
, order
, migratetype
);
945 * Use MIGRATE_RESERVE rather than fail an allocation. goto
946 * is used because __rmqueue_smallest is an inline function
947 * and we want just one call site
950 migratetype
= MIGRATE_RESERVE
;
955 trace_mm_page_alloc_zone_locked(page
, order
, migratetype
);
960 * Obtain a specified number of elements from the buddy allocator, all under
961 * a single hold of the lock, for efficiency. Add them to the supplied list.
962 * Returns the number of new pages which were placed at *list.
964 static int rmqueue_bulk(struct zone
*zone
, unsigned int order
,
965 unsigned long count
, struct list_head
*list
,
966 int migratetype
, int cold
)
970 spin_lock(&zone
->lock
);
971 for (i
= 0; i
< count
; ++i
) {
972 struct page
*page
= __rmqueue(zone
, order
, migratetype
);
973 if (unlikely(page
== NULL
))
977 * Split buddy pages returned by expand() are received here
978 * in physical page order. The page is added to the callers and
979 * list and the list head then moves forward. From the callers
980 * perspective, the linked list is ordered by page number in
981 * some conditions. This is useful for IO devices that can
982 * merge IO requests if the physical pages are ordered
985 if (likely(cold
== 0))
986 list_add(&page
->lru
, list
);
988 list_add_tail(&page
->lru
, list
);
989 set_page_private(page
, migratetype
);
992 __mod_zone_page_state(zone
, NR_FREE_PAGES
, -(i
<< order
));
993 spin_unlock(&zone
->lock
);
999 * Called from the vmstat counter updater to drain pagesets of this
1000 * currently executing processor on remote nodes after they have
1003 * Note that this function must be called with the thread pinned to
1004 * a single processor.
1006 void drain_zone_pages(struct zone
*zone
, struct per_cpu_pages
*pcp
)
1008 unsigned long flags
;
1011 local_irq_save(flags
);
1012 if (pcp
->count
>= pcp
->batch
)
1013 to_drain
= pcp
->batch
;
1015 to_drain
= pcp
->count
;
1016 free_pcppages_bulk(zone
, to_drain
, pcp
);
1017 pcp
->count
-= to_drain
;
1018 local_irq_restore(flags
);
1023 * Drain pages of the indicated processor.
1025 * The processor must either be the current processor and the
1026 * thread pinned to the current processor or a processor that
1029 static void drain_pages(unsigned int cpu
)
1031 unsigned long flags
;
1034 for_each_populated_zone(zone
) {
1035 struct per_cpu_pageset
*pset
;
1036 struct per_cpu_pages
*pcp
;
1038 local_irq_save(flags
);
1039 pset
= per_cpu_ptr(zone
->pageset
, cpu
);
1042 free_pcppages_bulk(zone
, pcp
->count
, pcp
);
1044 local_irq_restore(flags
);
1049 * Spill all of this CPU's per-cpu pages back into the buddy allocator.
1051 void drain_local_pages(void *arg
)
1053 drain_pages(smp_processor_id());
1057 * Spill all the per-cpu pages from all CPUs back into the buddy allocator
1059 void drain_all_pages(void)
1061 on_each_cpu(drain_local_pages
, NULL
, 1);
1064 #ifdef CONFIG_HIBERNATION
1066 void mark_free_pages(struct zone
*zone
)
1068 unsigned long pfn
, max_zone_pfn
;
1069 unsigned long flags
;
1071 struct list_head
*curr
;
1073 if (!zone
->spanned_pages
)
1076 spin_lock_irqsave(&zone
->lock
, flags
);
1078 max_zone_pfn
= zone
->zone_start_pfn
+ zone
->spanned_pages
;
1079 for (pfn
= zone
->zone_start_pfn
; pfn
< max_zone_pfn
; pfn
++)
1080 if (pfn_valid(pfn
)) {
1081 struct page
*page
= pfn_to_page(pfn
);
1083 if (!swsusp_page_is_forbidden(page
))
1084 swsusp_unset_page_free(page
);
1087 for_each_migratetype_order(order
, t
) {
1088 list_for_each(curr
, &zone
->free_area
[order
].free_list
[t
]) {
1091 pfn
= page_to_pfn(list_entry(curr
, struct page
, lru
));
1092 for (i
= 0; i
< (1UL << order
); i
++)
1093 swsusp_set_page_free(pfn_to_page(pfn
+ i
));
1096 spin_unlock_irqrestore(&zone
->lock
, flags
);
1098 #endif /* CONFIG_PM */
1101 * Free a 0-order page
1102 * cold == 1 ? free a cold page : free a hot page
1104 void free_hot_cold_page(struct page
*page
, int cold
)
1106 struct zone
*zone
= page_zone(page
);
1107 struct per_cpu_pages
*pcp
;
1108 unsigned long flags
;
1110 int wasMlocked
= __TestClearPageMlocked(page
);
1112 trace_mm_page_free_direct(page
, 0);
1113 kmemcheck_free_shadow(page
, 0);
1116 page
->mapping
= NULL
;
1117 if (free_pages_check(page
))
1120 if (!PageHighMem(page
)) {
1121 debug_check_no_locks_freed(page_address(page
), PAGE_SIZE
);
1122 debug_check_no_obj_freed(page_address(page
), PAGE_SIZE
);
1124 arch_free_page(page
, 0);
1125 kernel_map_pages(page
, 1, 0);
1127 migratetype
= get_pageblock_migratetype(page
);
1128 set_page_private(page
, migratetype
);
1129 local_irq_save(flags
);
1130 if (unlikely(wasMlocked
))
1131 free_page_mlock(page
);
1132 __count_vm_event(PGFREE
);
1135 * We only track unmovable, reclaimable and movable on pcp lists.
1136 * Free ISOLATE pages back to the allocator because they are being
1137 * offlined but treat RESERVE as movable pages so we can get those
1138 * areas back if necessary. Otherwise, we may have to free
1139 * excessively into the page allocator
1141 if (migratetype
>= MIGRATE_PCPTYPES
) {
1142 if (unlikely(migratetype
== MIGRATE_ISOLATE
)) {
1143 free_one_page(zone
, page
, 0, migratetype
);
1146 migratetype
= MIGRATE_MOVABLE
;
1149 pcp
= &this_cpu_ptr(zone
->pageset
)->pcp
;
1151 list_add_tail(&page
->lru
, &pcp
->lists
[migratetype
]);
1153 list_add(&page
->lru
, &pcp
->lists
[migratetype
]);
1155 if (pcp
->count
>= pcp
->high
) {
1156 free_pcppages_bulk(zone
, pcp
->batch
, pcp
);
1157 pcp
->count
-= pcp
->batch
;
1161 local_irq_restore(flags
);
1165 * split_page takes a non-compound higher-order page, and splits it into
1166 * n (1<<order) sub-pages: page[0..n]
1167 * Each sub-page must be freed individually.
1169 * Note: this is probably too low level an operation for use in drivers.
1170 * Please consult with lkml before using this in your driver.
1172 void split_page(struct page
*page
, unsigned int order
)
1176 VM_BUG_ON(PageCompound(page
));
1177 VM_BUG_ON(!page_count(page
));
1179 #ifdef CONFIG_KMEMCHECK
1181 * Split shadow pages too, because free(page[0]) would
1182 * otherwise free the whole shadow.
1184 if (kmemcheck_page_is_tracked(page
))
1185 split_page(virt_to_page(page
[0].shadow
), order
);
1188 for (i
= 1; i
< (1 << order
); i
++)
1189 set_page_refcounted(page
+ i
);
1193 * Really, prep_compound_page() should be called from __rmqueue_bulk(). But
1194 * we cheat by calling it from here, in the order > 0 path. Saves a branch
1198 struct page
*buffered_rmqueue(struct zone
*preferred_zone
,
1199 struct zone
*zone
, int order
, gfp_t gfp_flags
,
1202 unsigned long flags
;
1204 int cold
= !!(gfp_flags
& __GFP_COLD
);
1207 if (likely(order
== 0)) {
1208 struct per_cpu_pages
*pcp
;
1209 struct list_head
*list
;
1211 local_irq_save(flags
);
1212 pcp
= &this_cpu_ptr(zone
->pageset
)->pcp
;
1213 list
= &pcp
->lists
[migratetype
];
1214 if (list_empty(list
)) {
1215 pcp
->count
+= rmqueue_bulk(zone
, 0,
1218 if (unlikely(list_empty(list
)))
1223 page
= list_entry(list
->prev
, struct page
, lru
);
1225 page
= list_entry(list
->next
, struct page
, lru
);
1227 list_del(&page
->lru
);
1230 if (unlikely(gfp_flags
& __GFP_NOFAIL
)) {
1232 * __GFP_NOFAIL is not to be used in new code.
1234 * All __GFP_NOFAIL callers should be fixed so that they
1235 * properly detect and handle allocation failures.
1237 * We most definitely don't want callers attempting to
1238 * allocate greater than order-1 page units with
1241 WARN_ON_ONCE(order
> 1);
1243 spin_lock_irqsave(&zone
->lock
, flags
);
1244 page
= __rmqueue(zone
, order
, migratetype
);
1245 spin_unlock(&zone
->lock
);
1248 __mod_zone_page_state(zone
, NR_FREE_PAGES
, -(1 << order
));
1251 __count_zone_vm_events(PGALLOC
, zone
, 1 << order
);
1252 zone_statistics(preferred_zone
, zone
);
1253 local_irq_restore(flags
);
1255 VM_BUG_ON(bad_range(zone
, page
));
1256 if (prep_new_page(page
, order
, gfp_flags
))
1261 local_irq_restore(flags
);
1265 /* The ALLOC_WMARK bits are used as an index to zone->watermark */
1266 #define ALLOC_WMARK_MIN WMARK_MIN
1267 #define ALLOC_WMARK_LOW WMARK_LOW
1268 #define ALLOC_WMARK_HIGH WMARK_HIGH
1269 #define ALLOC_NO_WATERMARKS 0x04 /* don't check watermarks at all */
1271 /* Mask to get the watermark bits */
1272 #define ALLOC_WMARK_MASK (ALLOC_NO_WATERMARKS-1)
1274 #define ALLOC_HARDER 0x10 /* try to alloc harder */
1275 #define ALLOC_HIGH 0x20 /* __GFP_HIGH set */
1276 #define ALLOC_CPUSET 0x40 /* check for correct cpuset */
1278 #ifdef CONFIG_FAIL_PAGE_ALLOC
1280 static struct fail_page_alloc_attr
{
1281 struct fault_attr attr
;
1283 u32 ignore_gfp_highmem
;
1284 u32 ignore_gfp_wait
;
1287 #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
1289 struct dentry
*ignore_gfp_highmem_file
;
1290 struct dentry
*ignore_gfp_wait_file
;
1291 struct dentry
*min_order_file
;
1293 #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
1295 } fail_page_alloc
= {
1296 .attr
= FAULT_ATTR_INITIALIZER
,
1297 .ignore_gfp_wait
= 1,
1298 .ignore_gfp_highmem
= 1,
1302 static int __init
setup_fail_page_alloc(char *str
)
1304 return setup_fault_attr(&fail_page_alloc
.attr
, str
);
1306 __setup("fail_page_alloc=", setup_fail_page_alloc
);
1308 static int should_fail_alloc_page(gfp_t gfp_mask
, unsigned int order
)
1310 if (order
< fail_page_alloc
.min_order
)
1312 if (gfp_mask
& __GFP_NOFAIL
)
1314 if (fail_page_alloc
.ignore_gfp_highmem
&& (gfp_mask
& __GFP_HIGHMEM
))
1316 if (fail_page_alloc
.ignore_gfp_wait
&& (gfp_mask
& __GFP_WAIT
))
1319 return should_fail(&fail_page_alloc
.attr
, 1 << order
);
1322 #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
1324 static int __init
fail_page_alloc_debugfs(void)
1326 mode_t mode
= S_IFREG
| S_IRUSR
| S_IWUSR
;
1330 err
= init_fault_attr_dentries(&fail_page_alloc
.attr
,
1334 dir
= fail_page_alloc
.attr
.dentries
.dir
;
1336 fail_page_alloc
.ignore_gfp_wait_file
=
1337 debugfs_create_bool("ignore-gfp-wait", mode
, dir
,
1338 &fail_page_alloc
.ignore_gfp_wait
);
1340 fail_page_alloc
.ignore_gfp_highmem_file
=
1341 debugfs_create_bool("ignore-gfp-highmem", mode
, dir
,
1342 &fail_page_alloc
.ignore_gfp_highmem
);
1343 fail_page_alloc
.min_order_file
=
1344 debugfs_create_u32("min-order", mode
, dir
,
1345 &fail_page_alloc
.min_order
);
1347 if (!fail_page_alloc
.ignore_gfp_wait_file
||
1348 !fail_page_alloc
.ignore_gfp_highmem_file
||
1349 !fail_page_alloc
.min_order_file
) {
1351 debugfs_remove(fail_page_alloc
.ignore_gfp_wait_file
);
1352 debugfs_remove(fail_page_alloc
.ignore_gfp_highmem_file
);
1353 debugfs_remove(fail_page_alloc
.min_order_file
);
1354 cleanup_fault_attr_dentries(&fail_page_alloc
.attr
);
1360 late_initcall(fail_page_alloc_debugfs
);
1362 #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
1364 #else /* CONFIG_FAIL_PAGE_ALLOC */
1366 static inline int should_fail_alloc_page(gfp_t gfp_mask
, unsigned int order
)
1371 #endif /* CONFIG_FAIL_PAGE_ALLOC */
1374 * Return 1 if free pages are above 'mark'. This takes into account the order
1375 * of the allocation.
1377 int zone_watermark_ok(struct zone
*z
, int order
, unsigned long mark
,
1378 int classzone_idx
, int alloc_flags
)
1380 /* free_pages my go negative - that's OK */
1382 long free_pages
= zone_page_state(z
, NR_FREE_PAGES
) - (1 << order
) + 1;
1385 if (alloc_flags
& ALLOC_HIGH
)
1387 if (alloc_flags
& ALLOC_HARDER
)
1390 if (free_pages
<= min
+ z
->lowmem_reserve
[classzone_idx
])
1392 for (o
= 0; o
< order
; o
++) {
1393 /* At the next order, this order's pages become unavailable */
1394 free_pages
-= z
->free_area
[o
].nr_free
<< o
;
1396 /* Require fewer higher order pages to be free */
1399 if (free_pages
<= min
)
1407 * zlc_setup - Setup for "zonelist cache". Uses cached zone data to
1408 * skip over zones that are not allowed by the cpuset, or that have
1409 * been recently (in last second) found to be nearly full. See further
1410 * comments in mmzone.h. Reduces cache footprint of zonelist scans
1411 * that have to skip over a lot of full or unallowed zones.
1413 * If the zonelist cache is present in the passed in zonelist, then
1414 * returns a pointer to the allowed node mask (either the current
1415 * tasks mems_allowed, or node_states[N_HIGH_MEMORY].)
1417 * If the zonelist cache is not available for this zonelist, does
1418 * nothing and returns NULL.
1420 * If the fullzones BITMAP in the zonelist cache is stale (more than
1421 * a second since last zap'd) then we zap it out (clear its bits.)
1423 * We hold off even calling zlc_setup, until after we've checked the
1424 * first zone in the zonelist, on the theory that most allocations will
1425 * be satisfied from that first zone, so best to examine that zone as
1426 * quickly as we can.
1428 static nodemask_t
*zlc_setup(struct zonelist
*zonelist
, int alloc_flags
)
1430 struct zonelist_cache
*zlc
; /* cached zonelist speedup info */
1431 nodemask_t
*allowednodes
; /* zonelist_cache approximation */
1433 zlc
= zonelist
->zlcache_ptr
;
1437 if (time_after(jiffies
, zlc
->last_full_zap
+ HZ
)) {
1438 bitmap_zero(zlc
->fullzones
, MAX_ZONES_PER_ZONELIST
);
1439 zlc
->last_full_zap
= jiffies
;
1442 allowednodes
= !in_interrupt() && (alloc_flags
& ALLOC_CPUSET
) ?
1443 &cpuset_current_mems_allowed
:
1444 &node_states
[N_HIGH_MEMORY
];
1445 return allowednodes
;
1449 * Given 'z' scanning a zonelist, run a couple of quick checks to see
1450 * if it is worth looking at further for free memory:
1451 * 1) Check that the zone isn't thought to be full (doesn't have its
1452 * bit set in the zonelist_cache fullzones BITMAP).
1453 * 2) Check that the zones node (obtained from the zonelist_cache
1454 * z_to_n[] mapping) is allowed in the passed in allowednodes mask.
1455 * Return true (non-zero) if zone is worth looking at further, or
1456 * else return false (zero) if it is not.
1458 * This check -ignores- the distinction between various watermarks,
1459 * such as GFP_HIGH, GFP_ATOMIC, PF_MEMALLOC, ... If a zone is
1460 * found to be full for any variation of these watermarks, it will
1461 * be considered full for up to one second by all requests, unless
1462 * we are so low on memory on all allowed nodes that we are forced
1463 * into the second scan of the zonelist.
1465 * In the second scan we ignore this zonelist cache and exactly
1466 * apply the watermarks to all zones, even it is slower to do so.
1467 * We are low on memory in the second scan, and should leave no stone
1468 * unturned looking for a free page.
1470 static int zlc_zone_worth_trying(struct zonelist
*zonelist
, struct zoneref
*z
,
1471 nodemask_t
*allowednodes
)
1473 struct zonelist_cache
*zlc
; /* cached zonelist speedup info */
1474 int i
; /* index of *z in zonelist zones */
1475 int n
; /* node that zone *z is on */
1477 zlc
= zonelist
->zlcache_ptr
;
1481 i
= z
- zonelist
->_zonerefs
;
1484 /* This zone is worth trying if it is allowed but not full */
1485 return node_isset(n
, *allowednodes
) && !test_bit(i
, zlc
->fullzones
);
1489 * Given 'z' scanning a zonelist, set the corresponding bit in
1490 * zlc->fullzones, so that subsequent attempts to allocate a page
1491 * from that zone don't waste time re-examining it.
1493 static void zlc_mark_zone_full(struct zonelist
*zonelist
, struct zoneref
*z
)
1495 struct zonelist_cache
*zlc
; /* cached zonelist speedup info */
1496 int i
; /* index of *z in zonelist zones */
1498 zlc
= zonelist
->zlcache_ptr
;
1502 i
= z
- zonelist
->_zonerefs
;
1504 set_bit(i
, zlc
->fullzones
);
1507 #else /* CONFIG_NUMA */
1509 static nodemask_t
*zlc_setup(struct zonelist
*zonelist
, int alloc_flags
)
1514 static int zlc_zone_worth_trying(struct zonelist
*zonelist
, struct zoneref
*z
,
1515 nodemask_t
*allowednodes
)
1520 static void zlc_mark_zone_full(struct zonelist
*zonelist
, struct zoneref
*z
)
1523 #endif /* CONFIG_NUMA */
1526 * get_page_from_freelist goes through the zonelist trying to allocate
1529 static struct page
*
1530 get_page_from_freelist(gfp_t gfp_mask
, nodemask_t
*nodemask
, unsigned int order
,
1531 struct zonelist
*zonelist
, int high_zoneidx
, int alloc_flags
,
1532 struct zone
*preferred_zone
, int migratetype
)
1535 struct page
*page
= NULL
;
1538 nodemask_t
*allowednodes
= NULL
;/* zonelist_cache approximation */
1539 int zlc_active
= 0; /* set if using zonelist_cache */
1540 int did_zlc_setup
= 0; /* just call zlc_setup() one time */
1542 classzone_idx
= zone_idx(preferred_zone
);
1545 * Scan zonelist, looking for a zone with enough free.
1546 * See also cpuset_zone_allowed() comment in kernel/cpuset.c.
1548 for_each_zone_zonelist_nodemask(zone
, z
, zonelist
,
1549 high_zoneidx
, nodemask
) {
1550 if (NUMA_BUILD
&& zlc_active
&&
1551 !zlc_zone_worth_trying(zonelist
, z
, allowednodes
))
1553 if ((alloc_flags
& ALLOC_CPUSET
) &&
1554 !cpuset_zone_allowed_softwall(zone
, gfp_mask
))
1557 BUILD_BUG_ON(ALLOC_NO_WATERMARKS
< NR_WMARK
);
1558 if (!(alloc_flags
& ALLOC_NO_WATERMARKS
)) {
1562 mark
= zone
->watermark
[alloc_flags
& ALLOC_WMARK_MASK
];
1563 if (zone_watermark_ok(zone
, order
, mark
,
1564 classzone_idx
, alloc_flags
))
1567 if (zone_reclaim_mode
== 0)
1568 goto this_zone_full
;
1570 ret
= zone_reclaim(zone
, gfp_mask
, order
);
1572 case ZONE_RECLAIM_NOSCAN
:
1575 case ZONE_RECLAIM_FULL
:
1576 /* scanned but unreclaimable */
1577 goto this_zone_full
;
1579 /* did we reclaim enough */
1580 if (!zone_watermark_ok(zone
, order
, mark
,
1581 classzone_idx
, alloc_flags
))
1582 goto this_zone_full
;
1587 page
= buffered_rmqueue(preferred_zone
, zone
, order
,
1588 gfp_mask
, migratetype
);
1593 zlc_mark_zone_full(zonelist
, z
);
1595 if (NUMA_BUILD
&& !did_zlc_setup
&& nr_online_nodes
> 1) {
1597 * we do zlc_setup after the first zone is tried but only
1598 * if there are multiple nodes make it worthwhile
1600 allowednodes
= zlc_setup(zonelist
, alloc_flags
);
1606 if (unlikely(NUMA_BUILD
&& page
== NULL
&& zlc_active
)) {
1607 /* Disable zlc cache for second zonelist scan */
1615 should_alloc_retry(gfp_t gfp_mask
, unsigned int order
,
1616 unsigned long pages_reclaimed
)
1618 /* Do not loop if specifically requested */
1619 if (gfp_mask
& __GFP_NORETRY
)
1623 * In this implementation, order <= PAGE_ALLOC_COSTLY_ORDER
1624 * means __GFP_NOFAIL, but that may not be true in other
1627 if (order
<= PAGE_ALLOC_COSTLY_ORDER
)
1631 * For order > PAGE_ALLOC_COSTLY_ORDER, if __GFP_REPEAT is
1632 * specified, then we retry until we no longer reclaim any pages
1633 * (above), or we've reclaimed an order of pages at least as
1634 * large as the allocation's order. In both cases, if the
1635 * allocation still fails, we stop retrying.
1637 if (gfp_mask
& __GFP_REPEAT
&& pages_reclaimed
< (1 << order
))
1641 * Don't let big-order allocations loop unless the caller
1642 * explicitly requests that.
1644 if (gfp_mask
& __GFP_NOFAIL
)
1650 static inline struct page
*
1651 __alloc_pages_may_oom(gfp_t gfp_mask
, unsigned int order
,
1652 struct zonelist
*zonelist
, enum zone_type high_zoneidx
,
1653 nodemask_t
*nodemask
, struct zone
*preferred_zone
,
1658 /* Acquire the OOM killer lock for the zones in zonelist */
1659 if (!try_set_zone_oom(zonelist
, gfp_mask
)) {
1660 schedule_timeout_uninterruptible(1);
1665 * Go through the zonelist yet one more time, keep very high watermark
1666 * here, this is only to catch a parallel oom killing, we must fail if
1667 * we're still under heavy pressure.
1669 page
= get_page_from_freelist(gfp_mask
|__GFP_HARDWALL
, nodemask
,
1670 order
, zonelist
, high_zoneidx
,
1671 ALLOC_WMARK_HIGH
|ALLOC_CPUSET
,
1672 preferred_zone
, migratetype
);
1676 if (!(gfp_mask
& __GFP_NOFAIL
)) {
1677 /* The OOM killer will not help higher order allocs */
1678 if (order
> PAGE_ALLOC_COSTLY_ORDER
)
1681 * GFP_THISNODE contains __GFP_NORETRY and we never hit this.
1682 * Sanity check for bare calls of __GFP_THISNODE, not real OOM.
1683 * The caller should handle page allocation failure by itself if
1684 * it specifies __GFP_THISNODE.
1685 * Note: Hugepage uses it but will hit PAGE_ALLOC_COSTLY_ORDER.
1687 if (gfp_mask
& __GFP_THISNODE
)
1690 /* Exhausted what can be done so it's blamo time */
1691 out_of_memory(zonelist
, gfp_mask
, order
, nodemask
);
1694 clear_zonelist_oom(zonelist
, gfp_mask
);
1698 /* The really slow allocator path where we enter direct reclaim */
1699 static inline struct page
*
1700 __alloc_pages_direct_reclaim(gfp_t gfp_mask
, unsigned int order
,
1701 struct zonelist
*zonelist
, enum zone_type high_zoneidx
,
1702 nodemask_t
*nodemask
, int alloc_flags
, struct zone
*preferred_zone
,
1703 int migratetype
, unsigned long *did_some_progress
)
1705 struct page
*page
= NULL
;
1706 struct reclaim_state reclaim_state
;
1707 struct task_struct
*p
= current
;
1711 /* We now go into synchronous reclaim */
1712 cpuset_memory_pressure_bump();
1713 p
->flags
|= PF_MEMALLOC
;
1714 lockdep_set_current_reclaim_state(gfp_mask
);
1715 reclaim_state
.reclaimed_slab
= 0;
1716 p
->reclaim_state
= &reclaim_state
;
1718 *did_some_progress
= try_to_free_pages(zonelist
, order
, gfp_mask
, nodemask
);
1720 p
->reclaim_state
= NULL
;
1721 lockdep_clear_current_reclaim_state();
1722 p
->flags
&= ~PF_MEMALLOC
;
1729 if (likely(*did_some_progress
))
1730 page
= get_page_from_freelist(gfp_mask
, nodemask
, order
,
1731 zonelist
, high_zoneidx
,
1732 alloc_flags
, preferred_zone
,
1738 * This is called in the allocator slow-path if the allocation request is of
1739 * sufficient urgency to ignore watermarks and take other desperate measures
1741 static inline struct page
*
1742 __alloc_pages_high_priority(gfp_t gfp_mask
, unsigned int order
,
1743 struct zonelist
*zonelist
, enum zone_type high_zoneidx
,
1744 nodemask_t
*nodemask
, struct zone
*preferred_zone
,
1750 page
= get_page_from_freelist(gfp_mask
, nodemask
, order
,
1751 zonelist
, high_zoneidx
, ALLOC_NO_WATERMARKS
,
1752 preferred_zone
, migratetype
);
1754 if (!page
&& gfp_mask
& __GFP_NOFAIL
)
1755 congestion_wait(BLK_RW_ASYNC
, HZ
/50);
1756 } while (!page
&& (gfp_mask
& __GFP_NOFAIL
));
1762 void wake_all_kswapd(unsigned int order
, struct zonelist
*zonelist
,
1763 enum zone_type high_zoneidx
)
1768 for_each_zone_zonelist(zone
, z
, zonelist
, high_zoneidx
)
1769 wakeup_kswapd(zone
, order
);
1773 gfp_to_alloc_flags(gfp_t gfp_mask
)
1775 struct task_struct
*p
= current
;
1776 int alloc_flags
= ALLOC_WMARK_MIN
| ALLOC_CPUSET
;
1777 const gfp_t wait
= gfp_mask
& __GFP_WAIT
;
1779 /* __GFP_HIGH is assumed to be the same as ALLOC_HIGH to save a branch. */
1780 BUILD_BUG_ON(__GFP_HIGH
!= ALLOC_HIGH
);
1783 * The caller may dip into page reserves a bit more if the caller
1784 * cannot run direct reclaim, or if the caller has realtime scheduling
1785 * policy or is asking for __GFP_HIGH memory. GFP_ATOMIC requests will
1786 * set both ALLOC_HARDER (!wait) and ALLOC_HIGH (__GFP_HIGH).
1788 alloc_flags
|= (gfp_mask
& __GFP_HIGH
);
1791 alloc_flags
|= ALLOC_HARDER
;
1793 * Ignore cpuset if GFP_ATOMIC (!wait) rather than fail alloc.
1794 * See also cpuset_zone_allowed() comment in kernel/cpuset.c.
1796 alloc_flags
&= ~ALLOC_CPUSET
;
1797 } else if (unlikely(rt_task(p
)) && !in_interrupt())
1798 alloc_flags
|= ALLOC_HARDER
;
1800 if (likely(!(gfp_mask
& __GFP_NOMEMALLOC
))) {
1801 if (!in_interrupt() &&
1802 ((p
->flags
& PF_MEMALLOC
) ||
1803 unlikely(test_thread_flag(TIF_MEMDIE
))))
1804 alloc_flags
|= ALLOC_NO_WATERMARKS
;
1810 static inline struct page
*
1811 __alloc_pages_slowpath(gfp_t gfp_mask
, unsigned int order
,
1812 struct zonelist
*zonelist
, enum zone_type high_zoneidx
,
1813 nodemask_t
*nodemask
, struct zone
*preferred_zone
,
1816 const gfp_t wait
= gfp_mask
& __GFP_WAIT
;
1817 struct page
*page
= NULL
;
1819 unsigned long pages_reclaimed
= 0;
1820 unsigned long did_some_progress
;
1821 struct task_struct
*p
= current
;
1824 * In the slowpath, we sanity check order to avoid ever trying to
1825 * reclaim >= MAX_ORDER areas which will never succeed. Callers may
1826 * be using allocators in order of preference for an area that is
1829 if (order
>= MAX_ORDER
) {
1830 WARN_ON_ONCE(!(gfp_mask
& __GFP_NOWARN
));
1835 * GFP_THISNODE (meaning __GFP_THISNODE, __GFP_NORETRY and
1836 * __GFP_NOWARN set) should not cause reclaim since the subsystem
1837 * (f.e. slab) using GFP_THISNODE may choose to trigger reclaim
1838 * using a larger set of nodes after it has established that the
1839 * allowed per node queues are empty and that nodes are
1842 if (NUMA_BUILD
&& (gfp_mask
& GFP_THISNODE
) == GFP_THISNODE
)
1846 wake_all_kswapd(order
, zonelist
, high_zoneidx
);
1849 * OK, we're below the kswapd watermark and have kicked background
1850 * reclaim. Now things get more complex, so set up alloc_flags according
1851 * to how we want to proceed.
1853 alloc_flags
= gfp_to_alloc_flags(gfp_mask
);
1855 /* This is the last chance, in general, before the goto nopage. */
1856 page
= get_page_from_freelist(gfp_mask
, nodemask
, order
, zonelist
,
1857 high_zoneidx
, alloc_flags
& ~ALLOC_NO_WATERMARKS
,
1858 preferred_zone
, migratetype
);
1863 /* Allocate without watermarks if the context allows */
1864 if (alloc_flags
& ALLOC_NO_WATERMARKS
) {
1865 page
= __alloc_pages_high_priority(gfp_mask
, order
,
1866 zonelist
, high_zoneidx
, nodemask
,
1867 preferred_zone
, migratetype
);
1872 /* Atomic allocations - we can't balance anything */
1876 /* Avoid recursion of direct reclaim */
1877 if (p
->flags
& PF_MEMALLOC
)
1880 /* Avoid allocations with no watermarks from looping endlessly */
1881 if (test_thread_flag(TIF_MEMDIE
) && !(gfp_mask
& __GFP_NOFAIL
))
1884 /* Try direct reclaim and then allocating */
1885 page
= __alloc_pages_direct_reclaim(gfp_mask
, order
,
1886 zonelist
, high_zoneidx
,
1888 alloc_flags
, preferred_zone
,
1889 migratetype
, &did_some_progress
);
1894 * If we failed to make any progress reclaiming, then we are
1895 * running out of options and have to consider going OOM
1897 if (!did_some_progress
) {
1898 if ((gfp_mask
& __GFP_FS
) && !(gfp_mask
& __GFP_NORETRY
)) {
1899 if (oom_killer_disabled
)
1901 page
= __alloc_pages_may_oom(gfp_mask
, order
,
1902 zonelist
, high_zoneidx
,
1903 nodemask
, preferred_zone
,
1909 * The OOM killer does not trigger for high-order
1910 * ~__GFP_NOFAIL allocations so if no progress is being
1911 * made, there are no other options and retrying is
1914 if (order
> PAGE_ALLOC_COSTLY_ORDER
&&
1915 !(gfp_mask
& __GFP_NOFAIL
))
1922 /* Check if we should retry the allocation */
1923 pages_reclaimed
+= did_some_progress
;
1924 if (should_alloc_retry(gfp_mask
, order
, pages_reclaimed
)) {
1925 /* Wait for some write requests to complete then retry */
1926 congestion_wait(BLK_RW_ASYNC
, HZ
/50);
1931 if (!(gfp_mask
& __GFP_NOWARN
) && printk_ratelimit()) {
1932 printk(KERN_WARNING
"%s: page allocation failure."
1933 " order:%d, mode:0x%x\n",
1934 p
->comm
, order
, gfp_mask
);
1940 if (kmemcheck_enabled
)
1941 kmemcheck_pagealloc_alloc(page
, order
, gfp_mask
);
1947 * This is the 'heart' of the zoned buddy allocator.
1950 __alloc_pages_nodemask(gfp_t gfp_mask
, unsigned int order
,
1951 struct zonelist
*zonelist
, nodemask_t
*nodemask
)
1953 enum zone_type high_zoneidx
= gfp_zone(gfp_mask
);
1954 struct zone
*preferred_zone
;
1956 int migratetype
= allocflags_to_migratetype(gfp_mask
);
1958 gfp_mask
&= gfp_allowed_mask
;
1960 lockdep_trace_alloc(gfp_mask
);
1962 might_sleep_if(gfp_mask
& __GFP_WAIT
);
1964 if (should_fail_alloc_page(gfp_mask
, order
))
1968 * Check the zones suitable for the gfp_mask contain at least one
1969 * valid zone. It's possible to have an empty zonelist as a result
1970 * of GFP_THISNODE and a memoryless node
1972 if (unlikely(!zonelist
->_zonerefs
->zone
))
1975 /* The preferred zone is used for statistics later */
1976 first_zones_zonelist(zonelist
, high_zoneidx
, nodemask
, &preferred_zone
);
1977 if (!preferred_zone
)
1980 /* First allocation attempt */
1981 page
= get_page_from_freelist(gfp_mask
|__GFP_HARDWALL
, nodemask
, order
,
1982 zonelist
, high_zoneidx
, ALLOC_WMARK_LOW
|ALLOC_CPUSET
,
1983 preferred_zone
, migratetype
);
1984 if (unlikely(!page
))
1985 page
= __alloc_pages_slowpath(gfp_mask
, order
,
1986 zonelist
, high_zoneidx
, nodemask
,
1987 preferred_zone
, migratetype
);
1989 trace_mm_page_alloc(page
, order
, gfp_mask
, migratetype
);
1992 EXPORT_SYMBOL(__alloc_pages_nodemask
);
1995 * Common helper functions.
1997 unsigned long __get_free_pages(gfp_t gfp_mask
, unsigned int order
)
2002 * __get_free_pages() returns a 32-bit address, which cannot represent
2005 VM_BUG_ON((gfp_mask
& __GFP_HIGHMEM
) != 0);
2007 page
= alloc_pages(gfp_mask
, order
);
2010 return (unsigned long) page_address(page
);
2012 EXPORT_SYMBOL(__get_free_pages
);
2014 unsigned long get_zeroed_page(gfp_t gfp_mask
)
2016 return __get_free_pages(gfp_mask
| __GFP_ZERO
, 0);
2018 EXPORT_SYMBOL(get_zeroed_page
);
2020 void __pagevec_free(struct pagevec
*pvec
)
2022 int i
= pagevec_count(pvec
);
2025 trace_mm_pagevec_free(pvec
->pages
[i
], pvec
->cold
);
2026 free_hot_cold_page(pvec
->pages
[i
], pvec
->cold
);
2030 void __free_pages(struct page
*page
, unsigned int order
)
2032 if (put_page_testzero(page
)) {
2034 free_hot_cold_page(page
, 0);
2036 __free_pages_ok(page
, order
);
2040 EXPORT_SYMBOL(__free_pages
);
2042 void free_pages(unsigned long addr
, unsigned int order
)
2045 VM_BUG_ON(!virt_addr_valid((void *)addr
));
2046 __free_pages(virt_to_page((void *)addr
), order
);
2050 EXPORT_SYMBOL(free_pages
);
2053 * alloc_pages_exact - allocate an exact number physically-contiguous pages.
2054 * @size: the number of bytes to allocate
2055 * @gfp_mask: GFP flags for the allocation
2057 * This function is similar to alloc_pages(), except that it allocates the
2058 * minimum number of pages to satisfy the request. alloc_pages() can only
2059 * allocate memory in power-of-two pages.
2061 * This function is also limited by MAX_ORDER.
2063 * Memory allocated by this function must be released by free_pages_exact().
2065 void *alloc_pages_exact(size_t size
, gfp_t gfp_mask
)
2067 unsigned int order
= get_order(size
);
2070 addr
= __get_free_pages(gfp_mask
, order
);
2072 unsigned long alloc_end
= addr
+ (PAGE_SIZE
<< order
);
2073 unsigned long used
= addr
+ PAGE_ALIGN(size
);
2075 split_page(virt_to_page((void *)addr
), order
);
2076 while (used
< alloc_end
) {
2082 return (void *)addr
;
2084 EXPORT_SYMBOL(alloc_pages_exact
);
2087 * free_pages_exact - release memory allocated via alloc_pages_exact()
2088 * @virt: the value returned by alloc_pages_exact.
2089 * @size: size of allocation, same value as passed to alloc_pages_exact().
2091 * Release the memory allocated by a previous call to alloc_pages_exact.
2093 void free_pages_exact(void *virt
, size_t size
)
2095 unsigned long addr
= (unsigned long)virt
;
2096 unsigned long end
= addr
+ PAGE_ALIGN(size
);
2098 while (addr
< end
) {
2103 EXPORT_SYMBOL(free_pages_exact
);
2105 static unsigned int nr_free_zone_pages(int offset
)
2110 /* Just pick one node, since fallback list is circular */
2111 unsigned int sum
= 0;
2113 struct zonelist
*zonelist
= node_zonelist(numa_node_id(), GFP_KERNEL
);
2115 for_each_zone_zonelist(zone
, z
, zonelist
, offset
) {
2116 unsigned long size
= zone
->present_pages
;
2117 unsigned long high
= high_wmark_pages(zone
);
2126 * Amount of free RAM allocatable within ZONE_DMA and ZONE_NORMAL
2128 unsigned int nr_free_buffer_pages(void)
2130 return nr_free_zone_pages(gfp_zone(GFP_USER
));
2132 EXPORT_SYMBOL_GPL(nr_free_buffer_pages
);
2135 * Amount of free RAM allocatable within all zones
2137 unsigned int nr_free_pagecache_pages(void)
2139 return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE
));
2142 static inline void show_node(struct zone
*zone
)
2145 printk("Node %d ", zone_to_nid(zone
));
2148 void si_meminfo(struct sysinfo
*val
)
2150 val
->totalram
= totalram_pages
;
2152 val
->freeram
= global_page_state(NR_FREE_PAGES
);
2153 val
->bufferram
= nr_blockdev_pages();
2154 val
->totalhigh
= totalhigh_pages
;
2155 val
->freehigh
= nr_free_highpages();
2156 val
->mem_unit
= PAGE_SIZE
;
2159 EXPORT_SYMBOL(si_meminfo
);
2162 void si_meminfo_node(struct sysinfo
*val
, int nid
)
2164 pg_data_t
*pgdat
= NODE_DATA(nid
);
2166 val
->totalram
= pgdat
->node_present_pages
;
2167 val
->freeram
= node_page_state(nid
, NR_FREE_PAGES
);
2168 #ifdef CONFIG_HIGHMEM
2169 val
->totalhigh
= pgdat
->node_zones
[ZONE_HIGHMEM
].present_pages
;
2170 val
->freehigh
= zone_page_state(&pgdat
->node_zones
[ZONE_HIGHMEM
],
2176 val
->mem_unit
= PAGE_SIZE
;
2180 #define K(x) ((x) << (PAGE_SHIFT-10))
2183 * Show free area list (used inside shift_scroll-lock stuff)
2184 * We also calculate the percentage fragmentation. We do this by counting the
2185 * memory on each free list with the exception of the first item on the list.
2187 void show_free_areas(void)
2192 for_each_populated_zone(zone
) {
2194 printk("%s per-cpu:\n", zone
->name
);
2196 for_each_online_cpu(cpu
) {
2197 struct per_cpu_pageset
*pageset
;
2199 pageset
= per_cpu_ptr(zone
->pageset
, cpu
);
2201 printk("CPU %4d: hi:%5d, btch:%4d usd:%4d\n",
2202 cpu
, pageset
->pcp
.high
,
2203 pageset
->pcp
.batch
, pageset
->pcp
.count
);
2207 printk("active_anon:%lu inactive_anon:%lu isolated_anon:%lu\n"
2208 " active_file:%lu inactive_file:%lu isolated_file:%lu\n"
2210 " dirty:%lu writeback:%lu unstable:%lu\n"
2211 " free:%lu slab_reclaimable:%lu slab_unreclaimable:%lu\n"
2212 " mapped:%lu shmem:%lu pagetables:%lu bounce:%lu\n",
2213 global_page_state(NR_ACTIVE_ANON
),
2214 global_page_state(NR_INACTIVE_ANON
),
2215 global_page_state(NR_ISOLATED_ANON
),
2216 global_page_state(NR_ACTIVE_FILE
),
2217 global_page_state(NR_INACTIVE_FILE
),
2218 global_page_state(NR_ISOLATED_FILE
),
2219 global_page_state(NR_UNEVICTABLE
),
2220 global_page_state(NR_FILE_DIRTY
),
2221 global_page_state(NR_WRITEBACK
),
2222 global_page_state(NR_UNSTABLE_NFS
),
2223 global_page_state(NR_FREE_PAGES
),
2224 global_page_state(NR_SLAB_RECLAIMABLE
),
2225 global_page_state(NR_SLAB_UNRECLAIMABLE
),
2226 global_page_state(NR_FILE_MAPPED
),
2227 global_page_state(NR_SHMEM
),
2228 global_page_state(NR_PAGETABLE
),
2229 global_page_state(NR_BOUNCE
));
2231 for_each_populated_zone(zone
) {
2240 " active_anon:%lukB"
2241 " inactive_anon:%lukB"
2242 " active_file:%lukB"
2243 " inactive_file:%lukB"
2244 " unevictable:%lukB"
2245 " isolated(anon):%lukB"
2246 " isolated(file):%lukB"
2253 " slab_reclaimable:%lukB"
2254 " slab_unreclaimable:%lukB"
2255 " kernel_stack:%lukB"
2259 " writeback_tmp:%lukB"
2260 " pages_scanned:%lu"
2261 " all_unreclaimable? %s"
2264 K(zone_page_state(zone
, NR_FREE_PAGES
)),
2265 K(min_wmark_pages(zone
)),
2266 K(low_wmark_pages(zone
)),
2267 K(high_wmark_pages(zone
)),
2268 K(zone_page_state(zone
, NR_ACTIVE_ANON
)),
2269 K(zone_page_state(zone
, NR_INACTIVE_ANON
)),
2270 K(zone_page_state(zone
, NR_ACTIVE_FILE
)),
2271 K(zone_page_state(zone
, NR_INACTIVE_FILE
)),
2272 K(zone_page_state(zone
, NR_UNEVICTABLE
)),
2273 K(zone_page_state(zone
, NR_ISOLATED_ANON
)),
2274 K(zone_page_state(zone
, NR_ISOLATED_FILE
)),
2275 K(zone
->present_pages
),
2276 K(zone_page_state(zone
, NR_MLOCK
)),
2277 K(zone_page_state(zone
, NR_FILE_DIRTY
)),
2278 K(zone_page_state(zone
, NR_WRITEBACK
)),
2279 K(zone_page_state(zone
, NR_FILE_MAPPED
)),
2280 K(zone_page_state(zone
, NR_SHMEM
)),
2281 K(zone_page_state(zone
, NR_SLAB_RECLAIMABLE
)),
2282 K(zone_page_state(zone
, NR_SLAB_UNRECLAIMABLE
)),
2283 zone_page_state(zone
, NR_KERNEL_STACK
) *
2285 K(zone_page_state(zone
, NR_PAGETABLE
)),
2286 K(zone_page_state(zone
, NR_UNSTABLE_NFS
)),
2287 K(zone_page_state(zone
, NR_BOUNCE
)),
2288 K(zone_page_state(zone
, NR_WRITEBACK_TEMP
)),
2289 zone
->pages_scanned
,
2290 (zone
->all_unreclaimable
? "yes" : "no")
2292 printk("lowmem_reserve[]:");
2293 for (i
= 0; i
< MAX_NR_ZONES
; i
++)
2294 printk(" %lu", zone
->lowmem_reserve
[i
]);
2298 for_each_populated_zone(zone
) {
2299 unsigned long nr
[MAX_ORDER
], flags
, order
, total
= 0;
2302 printk("%s: ", zone
->name
);
2304 spin_lock_irqsave(&zone
->lock
, flags
);
2305 for (order
= 0; order
< MAX_ORDER
; order
++) {
2306 nr
[order
] = zone
->free_area
[order
].nr_free
;
2307 total
+= nr
[order
] << order
;
2309 spin_unlock_irqrestore(&zone
->lock
, flags
);
2310 for (order
= 0; order
< MAX_ORDER
; order
++)
2311 printk("%lu*%lukB ", nr
[order
], K(1UL) << order
);
2312 printk("= %lukB\n", K(total
));
2315 printk("%ld total pagecache pages\n", global_page_state(NR_FILE_PAGES
));
2317 show_swap_cache_info();
2320 static void zoneref_set_zone(struct zone
*zone
, struct zoneref
*zoneref
)
2322 zoneref
->zone
= zone
;
2323 zoneref
->zone_idx
= zone_idx(zone
);
2327 * Builds allocation fallback zone lists.
2329 * Add all populated zones of a node to the zonelist.
2331 static int build_zonelists_node(pg_data_t
*pgdat
, struct zonelist
*zonelist
,
2332 int nr_zones
, enum zone_type zone_type
)
2336 BUG_ON(zone_type
>= MAX_NR_ZONES
);
2341 zone
= pgdat
->node_zones
+ zone_type
;
2342 if (populated_zone(zone
)) {
2343 zoneref_set_zone(zone
,
2344 &zonelist
->_zonerefs
[nr_zones
++]);
2345 check_highest_zone(zone_type
);
2348 } while (zone_type
);
2355 * 0 = automatic detection of better ordering.
2356 * 1 = order by ([node] distance, -zonetype)
2357 * 2 = order by (-zonetype, [node] distance)
2359 * If not NUMA, ZONELIST_ORDER_ZONE and ZONELIST_ORDER_NODE will create
2360 * the same zonelist. So only NUMA can configure this param.
2362 #define ZONELIST_ORDER_DEFAULT 0
2363 #define ZONELIST_ORDER_NODE 1
2364 #define ZONELIST_ORDER_ZONE 2
2366 /* zonelist order in the kernel.
2367 * set_zonelist_order() will set this to NODE or ZONE.
2369 static int current_zonelist_order
= ZONELIST_ORDER_DEFAULT
;
2370 static char zonelist_order_name
[3][8] = {"Default", "Node", "Zone"};
2374 /* The value user specified ....changed by config */
2375 static int user_zonelist_order
= ZONELIST_ORDER_DEFAULT
;
2376 /* string for sysctl */
2377 #define NUMA_ZONELIST_ORDER_LEN 16
2378 char numa_zonelist_order
[16] = "default";
2381 * interface for configure zonelist ordering.
2382 * command line option "numa_zonelist_order"
2383 * = "[dD]efault - default, automatic configuration.
2384 * = "[nN]ode - order by node locality, then by zone within node
2385 * = "[zZ]one - order by zone, then by locality within zone
2388 static int __parse_numa_zonelist_order(char *s
)
2390 if (*s
== 'd' || *s
== 'D') {
2391 user_zonelist_order
= ZONELIST_ORDER_DEFAULT
;
2392 } else if (*s
== 'n' || *s
== 'N') {
2393 user_zonelist_order
= ZONELIST_ORDER_NODE
;
2394 } else if (*s
== 'z' || *s
== 'Z') {
2395 user_zonelist_order
= ZONELIST_ORDER_ZONE
;
2398 "Ignoring invalid numa_zonelist_order value: "
2405 static __init
int setup_numa_zonelist_order(char *s
)
2408 return __parse_numa_zonelist_order(s
);
2411 early_param("numa_zonelist_order", setup_numa_zonelist_order
);
2414 * sysctl handler for numa_zonelist_order
2416 int numa_zonelist_order_handler(ctl_table
*table
, int write
,
2417 void __user
*buffer
, size_t *length
,
2420 char saved_string
[NUMA_ZONELIST_ORDER_LEN
];
2422 static DEFINE_MUTEX(zl_order_mutex
);
2424 mutex_lock(&zl_order_mutex
);
2426 strcpy(saved_string
, (char*)table
->data
);
2427 ret
= proc_dostring(table
, write
, buffer
, length
, ppos
);
2431 int oldval
= user_zonelist_order
;
2432 if (__parse_numa_zonelist_order((char*)table
->data
)) {
2434 * bogus value. restore saved string
2436 strncpy((char*)table
->data
, saved_string
,
2437 NUMA_ZONELIST_ORDER_LEN
);
2438 user_zonelist_order
= oldval
;
2439 } else if (oldval
!= user_zonelist_order
)
2440 build_all_zonelists();
2443 mutex_unlock(&zl_order_mutex
);
2448 #define MAX_NODE_LOAD (nr_online_nodes)
2449 static int node_load
[MAX_NUMNODES
];
2452 * find_next_best_node - find the next node that should appear in a given node's fallback list
2453 * @node: node whose fallback list we're appending
2454 * @used_node_mask: nodemask_t of already used nodes
2456 * We use a number of factors to determine which is the next node that should
2457 * appear on a given node's fallback list. The node should not have appeared
2458 * already in @node's fallback list, and it should be the next closest node
2459 * according to the distance array (which contains arbitrary distance values
2460 * from each node to each node in the system), and should also prefer nodes
2461 * with no CPUs, since presumably they'll have very little allocation pressure
2462 * on them otherwise.
2463 * It returns -1 if no node is found.
2465 static int find_next_best_node(int node
, nodemask_t
*used_node_mask
)
2468 int min_val
= INT_MAX
;
2470 const struct cpumask
*tmp
= cpumask_of_node(0);
2472 /* Use the local node if we haven't already */
2473 if (!node_isset(node
, *used_node_mask
)) {
2474 node_set(node
, *used_node_mask
);
2478 for_each_node_state(n
, N_HIGH_MEMORY
) {
2480 /* Don't want a node to appear more than once */
2481 if (node_isset(n
, *used_node_mask
))
2484 /* Use the distance array to find the distance */
2485 val
= node_distance(node
, n
);
2487 /* Penalize nodes under us ("prefer the next node") */
2490 /* Give preference to headless and unused nodes */
2491 tmp
= cpumask_of_node(n
);
2492 if (!cpumask_empty(tmp
))
2493 val
+= PENALTY_FOR_NODE_WITH_CPUS
;
2495 /* Slight preference for less loaded node */
2496 val
*= (MAX_NODE_LOAD
*MAX_NUMNODES
);
2497 val
+= node_load
[n
];
2499 if (val
< min_val
) {
2506 node_set(best_node
, *used_node_mask
);
2513 * Build zonelists ordered by node and zones within node.
2514 * This results in maximum locality--normal zone overflows into local
2515 * DMA zone, if any--but risks exhausting DMA zone.
2517 static void build_zonelists_in_node_order(pg_data_t
*pgdat
, int node
)
2520 struct zonelist
*zonelist
;
2522 zonelist
= &pgdat
->node_zonelists
[0];
2523 for (j
= 0; zonelist
->_zonerefs
[j
].zone
!= NULL
; j
++)
2525 j
= build_zonelists_node(NODE_DATA(node
), zonelist
, j
,
2527 zonelist
->_zonerefs
[j
].zone
= NULL
;
2528 zonelist
->_zonerefs
[j
].zone_idx
= 0;
2532 * Build gfp_thisnode zonelists
2534 static void build_thisnode_zonelists(pg_data_t
*pgdat
)
2537 struct zonelist
*zonelist
;
2539 zonelist
= &pgdat
->node_zonelists
[1];
2540 j
= build_zonelists_node(pgdat
, zonelist
, 0, MAX_NR_ZONES
- 1);
2541 zonelist
->_zonerefs
[j
].zone
= NULL
;
2542 zonelist
->_zonerefs
[j
].zone_idx
= 0;
2546 * Build zonelists ordered by zone and nodes within zones.
2547 * This results in conserving DMA zone[s] until all Normal memory is
2548 * exhausted, but results in overflowing to remote node while memory
2549 * may still exist in local DMA zone.
2551 static int node_order
[MAX_NUMNODES
];
2553 static void build_zonelists_in_zone_order(pg_data_t
*pgdat
, int nr_nodes
)
2556 int zone_type
; /* needs to be signed */
2558 struct zonelist
*zonelist
;
2560 zonelist
= &pgdat
->node_zonelists
[0];
2562 for (zone_type
= MAX_NR_ZONES
- 1; zone_type
>= 0; zone_type
--) {
2563 for (j
= 0; j
< nr_nodes
; j
++) {
2564 node
= node_order
[j
];
2565 z
= &NODE_DATA(node
)->node_zones
[zone_type
];
2566 if (populated_zone(z
)) {
2568 &zonelist
->_zonerefs
[pos
++]);
2569 check_highest_zone(zone_type
);
2573 zonelist
->_zonerefs
[pos
].zone
= NULL
;
2574 zonelist
->_zonerefs
[pos
].zone_idx
= 0;
2577 static int default_zonelist_order(void)
2580 unsigned long low_kmem_size
,total_size
;
2584 * ZONE_DMA and ZONE_DMA32 can be very small area in the sytem.
2585 * If they are really small and used heavily, the system can fall
2586 * into OOM very easily.
2587 * This function detect ZONE_DMA/DMA32 size and confgigures zone order.
2589 /* Is there ZONE_NORMAL ? (ex. ppc has only DMA zone..) */
2592 for_each_online_node(nid
) {
2593 for (zone_type
= 0; zone_type
< MAX_NR_ZONES
; zone_type
++) {
2594 z
= &NODE_DATA(nid
)->node_zones
[zone_type
];
2595 if (populated_zone(z
)) {
2596 if (zone_type
< ZONE_NORMAL
)
2597 low_kmem_size
+= z
->present_pages
;
2598 total_size
+= z
->present_pages
;
2602 if (!low_kmem_size
|| /* there are no DMA area. */
2603 low_kmem_size
> total_size
/2) /* DMA/DMA32 is big. */
2604 return ZONELIST_ORDER_NODE
;
2606 * look into each node's config.
2607 * If there is a node whose DMA/DMA32 memory is very big area on
2608 * local memory, NODE_ORDER may be suitable.
2610 average_size
= total_size
/
2611 (nodes_weight(node_states
[N_HIGH_MEMORY
]) + 1);
2612 for_each_online_node(nid
) {
2615 for (zone_type
= 0; zone_type
< MAX_NR_ZONES
; zone_type
++) {
2616 z
= &NODE_DATA(nid
)->node_zones
[zone_type
];
2617 if (populated_zone(z
)) {
2618 if (zone_type
< ZONE_NORMAL
)
2619 low_kmem_size
+= z
->present_pages
;
2620 total_size
+= z
->present_pages
;
2623 if (low_kmem_size
&&
2624 total_size
> average_size
&& /* ignore small node */
2625 low_kmem_size
> total_size
* 70/100)
2626 return ZONELIST_ORDER_NODE
;
2628 return ZONELIST_ORDER_ZONE
;
2631 static void set_zonelist_order(void)
2633 if (user_zonelist_order
== ZONELIST_ORDER_DEFAULT
)
2634 current_zonelist_order
= default_zonelist_order();
2636 current_zonelist_order
= user_zonelist_order
;
2639 static void build_zonelists(pg_data_t
*pgdat
)
2643 nodemask_t used_mask
;
2644 int local_node
, prev_node
;
2645 struct zonelist
*zonelist
;
2646 int order
= current_zonelist_order
;
2648 /* initialize zonelists */
2649 for (i
= 0; i
< MAX_ZONELISTS
; i
++) {
2650 zonelist
= pgdat
->node_zonelists
+ i
;
2651 zonelist
->_zonerefs
[0].zone
= NULL
;
2652 zonelist
->_zonerefs
[0].zone_idx
= 0;
2655 /* NUMA-aware ordering of nodes */
2656 local_node
= pgdat
->node_id
;
2657 load
= nr_online_nodes
;
2658 prev_node
= local_node
;
2659 nodes_clear(used_mask
);
2661 memset(node_order
, 0, sizeof(node_order
));
2664 while ((node
= find_next_best_node(local_node
, &used_mask
)) >= 0) {
2665 int distance
= node_distance(local_node
, node
);
2668 * If another node is sufficiently far away then it is better
2669 * to reclaim pages in a zone before going off node.
2671 if (distance
> RECLAIM_DISTANCE
)
2672 zone_reclaim_mode
= 1;
2675 * We don't want to pressure a particular node.
2676 * So adding penalty to the first node in same
2677 * distance group to make it round-robin.
2679 if (distance
!= node_distance(local_node
, prev_node
))
2680 node_load
[node
] = load
;
2684 if (order
== ZONELIST_ORDER_NODE
)
2685 build_zonelists_in_node_order(pgdat
, node
);
2687 node_order
[j
++] = node
; /* remember order */
2690 if (order
== ZONELIST_ORDER_ZONE
) {
2691 /* calculate node order -- i.e., DMA last! */
2692 build_zonelists_in_zone_order(pgdat
, j
);
2695 build_thisnode_zonelists(pgdat
);
2698 /* Construct the zonelist performance cache - see further mmzone.h */
2699 static void build_zonelist_cache(pg_data_t
*pgdat
)
2701 struct zonelist
*zonelist
;
2702 struct zonelist_cache
*zlc
;
2705 zonelist
= &pgdat
->node_zonelists
[0];
2706 zonelist
->zlcache_ptr
= zlc
= &zonelist
->zlcache
;
2707 bitmap_zero(zlc
->fullzones
, MAX_ZONES_PER_ZONELIST
);
2708 for (z
= zonelist
->_zonerefs
; z
->zone
; z
++)
2709 zlc
->z_to_n
[z
- zonelist
->_zonerefs
] = zonelist_node_idx(z
);
2713 #else /* CONFIG_NUMA */
2715 static void set_zonelist_order(void)
2717 current_zonelist_order
= ZONELIST_ORDER_ZONE
;
2720 static void build_zonelists(pg_data_t
*pgdat
)
2722 int node
, local_node
;
2724 struct zonelist
*zonelist
;
2726 local_node
= pgdat
->node_id
;
2728 zonelist
= &pgdat
->node_zonelists
[0];
2729 j
= build_zonelists_node(pgdat
, zonelist
, 0, MAX_NR_ZONES
- 1);
2732 * Now we build the zonelist so that it contains the zones
2733 * of all the other nodes.
2734 * We don't want to pressure a particular node, so when
2735 * building the zones for node N, we make sure that the
2736 * zones coming right after the local ones are those from
2737 * node N+1 (modulo N)
2739 for (node
= local_node
+ 1; node
< MAX_NUMNODES
; node
++) {
2740 if (!node_online(node
))
2742 j
= build_zonelists_node(NODE_DATA(node
), zonelist
, j
,
2745 for (node
= 0; node
< local_node
; node
++) {
2746 if (!node_online(node
))
2748 j
= build_zonelists_node(NODE_DATA(node
), zonelist
, j
,
2752 zonelist
->_zonerefs
[j
].zone
= NULL
;
2753 zonelist
->_zonerefs
[j
].zone_idx
= 0;
2756 /* non-NUMA variant of zonelist performance cache - just NULL zlcache_ptr */
2757 static void build_zonelist_cache(pg_data_t
*pgdat
)
2759 pgdat
->node_zonelists
[0].zlcache_ptr
= NULL
;
2762 #endif /* CONFIG_NUMA */
2765 * Boot pageset table. One per cpu which is going to be used for all
2766 * zones and all nodes. The parameters will be set in such a way
2767 * that an item put on a list will immediately be handed over to
2768 * the buddy list. This is safe since pageset manipulation is done
2769 * with interrupts disabled.
2771 * The boot_pagesets must be kept even after bootup is complete for
2772 * unused processors and/or zones. They do play a role for bootstrapping
2773 * hotplugged processors.
2775 * zoneinfo_show() and maybe other functions do
2776 * not check if the processor is online before following the pageset pointer.
2777 * Other parts of the kernel may not check if the zone is available.
2779 static void setup_pageset(struct per_cpu_pageset
*p
, unsigned long batch
);
2780 static DEFINE_PER_CPU(struct per_cpu_pageset
, boot_pageset
);
2782 /* return values int ....just for stop_machine() */
2783 static int __build_all_zonelists(void *dummy
)
2789 memset(node_load
, 0, sizeof(node_load
));
2791 for_each_online_node(nid
) {
2792 pg_data_t
*pgdat
= NODE_DATA(nid
);
2794 build_zonelists(pgdat
);
2795 build_zonelist_cache(pgdat
);
2799 * Initialize the boot_pagesets that are going to be used
2800 * for bootstrapping processors. The real pagesets for
2801 * each zone will be allocated later when the per cpu
2802 * allocator is available.
2804 * boot_pagesets are used also for bootstrapping offline
2805 * cpus if the system is already booted because the pagesets
2806 * are needed to initialize allocators on a specific cpu too.
2807 * F.e. the percpu allocator needs the page allocator which
2808 * needs the percpu allocator in order to allocate its pagesets
2809 * (a chicken-egg dilemma).
2811 for_each_possible_cpu(cpu
)
2812 setup_pageset(&per_cpu(boot_pageset
, cpu
), 0);
2817 void build_all_zonelists(void)
2819 set_zonelist_order();
2821 if (system_state
== SYSTEM_BOOTING
) {
2822 __build_all_zonelists(NULL
);
2823 mminit_verify_zonelist();
2824 cpuset_init_current_mems_allowed();
2826 /* we have to stop all cpus to guarantee there is no user
2828 stop_machine(__build_all_zonelists
, NULL
, NULL
);
2829 /* cpuset refresh routine should be here */
2831 vm_total_pages
= nr_free_pagecache_pages();
2833 * Disable grouping by mobility if the number of pages in the
2834 * system is too low to allow the mechanism to work. It would be
2835 * more accurate, but expensive to check per-zone. This check is
2836 * made on memory-hotadd so a system can start with mobility
2837 * disabled and enable it later
2839 if (vm_total_pages
< (pageblock_nr_pages
* MIGRATE_TYPES
))
2840 page_group_by_mobility_disabled
= 1;
2842 page_group_by_mobility_disabled
= 0;
2844 printk("Built %i zonelists in %s order, mobility grouping %s. "
2845 "Total pages: %ld\n",
2847 zonelist_order_name
[current_zonelist_order
],
2848 page_group_by_mobility_disabled
? "off" : "on",
2851 printk("Policy zone: %s\n", zone_names
[policy_zone
]);
2856 * Helper functions to size the waitqueue hash table.
2857 * Essentially these want to choose hash table sizes sufficiently
2858 * large so that collisions trying to wait on pages are rare.
2859 * But in fact, the number of active page waitqueues on typical
2860 * systems is ridiculously low, less than 200. So this is even
2861 * conservative, even though it seems large.
2863 * The constant PAGES_PER_WAITQUEUE specifies the ratio of pages to
2864 * waitqueues, i.e. the size of the waitq table given the number of pages.
2866 #define PAGES_PER_WAITQUEUE 256
2868 #ifndef CONFIG_MEMORY_HOTPLUG
2869 static inline unsigned long wait_table_hash_nr_entries(unsigned long pages
)
2871 unsigned long size
= 1;
2873 pages
/= PAGES_PER_WAITQUEUE
;
2875 while (size
< pages
)
2879 * Once we have dozens or even hundreds of threads sleeping
2880 * on IO we've got bigger problems than wait queue collision.
2881 * Limit the size of the wait table to a reasonable size.
2883 size
= min(size
, 4096UL);
2885 return max(size
, 4UL);
2889 * A zone's size might be changed by hot-add, so it is not possible to determine
2890 * a suitable size for its wait_table. So we use the maximum size now.
2892 * The max wait table size = 4096 x sizeof(wait_queue_head_t). ie:
2894 * i386 (preemption config) : 4096 x 16 = 64Kbyte.
2895 * ia64, x86-64 (no preemption): 4096 x 20 = 80Kbyte.
2896 * ia64, x86-64 (preemption) : 4096 x 24 = 96Kbyte.
2898 * The maximum entries are prepared when a zone's memory is (512K + 256) pages
2899 * or more by the traditional way. (See above). It equals:
2901 * i386, x86-64, powerpc(4K page size) : = ( 2G + 1M)byte.
2902 * ia64(16K page size) : = ( 8G + 4M)byte.
2903 * powerpc (64K page size) : = (32G +16M)byte.
2905 static inline unsigned long wait_table_hash_nr_entries(unsigned long pages
)
2912 * This is an integer logarithm so that shifts can be used later
2913 * to extract the more random high bits from the multiplicative
2914 * hash function before the remainder is taken.
2916 static inline unsigned long wait_table_bits(unsigned long size
)
2921 #define LONG_ALIGN(x) (((x)+(sizeof(long))-1)&~((sizeof(long))-1))
2924 * Mark a number of pageblocks as MIGRATE_RESERVE. The number
2925 * of blocks reserved is based on min_wmark_pages(zone). The memory within
2926 * the reserve will tend to store contiguous free pages. Setting min_free_kbytes
2927 * higher will lead to a bigger reserve which will get freed as contiguous
2928 * blocks as reclaim kicks in
2930 static void setup_zone_migrate_reserve(struct zone
*zone
)
2932 unsigned long start_pfn
, pfn
, end_pfn
;
2934 unsigned long block_migratetype
;
2937 /* Get the start pfn, end pfn and the number of blocks to reserve */
2938 start_pfn
= zone
->zone_start_pfn
;
2939 end_pfn
= start_pfn
+ zone
->spanned_pages
;
2940 reserve
= roundup(min_wmark_pages(zone
), pageblock_nr_pages
) >>
2944 * Reserve blocks are generally in place to help high-order atomic
2945 * allocations that are short-lived. A min_free_kbytes value that
2946 * would result in more than 2 reserve blocks for atomic allocations
2947 * is assumed to be in place to help anti-fragmentation for the
2948 * future allocation of hugepages at runtime.
2950 reserve
= min(2, reserve
);
2952 for (pfn
= start_pfn
; pfn
< end_pfn
; pfn
+= pageblock_nr_pages
) {
2953 if (!pfn_valid(pfn
))
2955 page
= pfn_to_page(pfn
);
2957 /* Watch out for overlapping nodes */
2958 if (page_to_nid(page
) != zone_to_nid(zone
))
2961 /* Blocks with reserved pages will never free, skip them. */
2962 if (PageReserved(page
))
2965 block_migratetype
= get_pageblock_migratetype(page
);
2967 /* If this block is reserved, account for it */
2968 if (reserve
> 0 && block_migratetype
== MIGRATE_RESERVE
) {
2973 /* Suitable for reserving if this block is movable */
2974 if (reserve
> 0 && block_migratetype
== MIGRATE_MOVABLE
) {
2975 set_pageblock_migratetype(page
, MIGRATE_RESERVE
);
2976 move_freepages_block(zone
, page
, MIGRATE_RESERVE
);
2982 * If the reserve is met and this is a previous reserved block,
2985 if (block_migratetype
== MIGRATE_RESERVE
) {
2986 set_pageblock_migratetype(page
, MIGRATE_MOVABLE
);
2987 move_freepages_block(zone
, page
, MIGRATE_MOVABLE
);
2993 * Initially all pages are reserved - free ones are freed
2994 * up by free_all_bootmem() once the early boot process is
2995 * done. Non-atomic initialization, single-pass.
2997 void __meminit
memmap_init_zone(unsigned long size
, int nid
, unsigned long zone
,
2998 unsigned long start_pfn
, enum memmap_context context
)
3001 unsigned long end_pfn
= start_pfn
+ size
;
3005 if (highest_memmap_pfn
< end_pfn
- 1)
3006 highest_memmap_pfn
= end_pfn
- 1;
3008 z
= &NODE_DATA(nid
)->node_zones
[zone
];
3009 for (pfn
= start_pfn
; pfn
< end_pfn
; pfn
++) {
3011 * There can be holes in boot-time mem_map[]s
3012 * handed to this function. They do not
3013 * exist on hotplugged memory.
3015 if (context
== MEMMAP_EARLY
) {
3016 if (!early_pfn_valid(pfn
))
3018 if (!early_pfn_in_nid(pfn
, nid
))
3021 page
= pfn_to_page(pfn
);
3022 set_page_links(page
, zone
, nid
, pfn
);
3023 mminit_verify_page_links(page
, zone
, nid
, pfn
);
3024 init_page_count(page
);
3025 reset_page_mapcount(page
);
3026 SetPageReserved(page
);
3028 * Mark the block movable so that blocks are reserved for
3029 * movable at startup. This will force kernel allocations
3030 * to reserve their blocks rather than leaking throughout
3031 * the address space during boot when many long-lived
3032 * kernel allocations are made. Later some blocks near
3033 * the start are marked MIGRATE_RESERVE by
3034 * setup_zone_migrate_reserve()
3036 * bitmap is created for zone's valid pfn range. but memmap
3037 * can be created for invalid pages (for alignment)
3038 * check here not to call set_pageblock_migratetype() against
3041 if ((z
->zone_start_pfn
<= pfn
)
3042 && (pfn
< z
->zone_start_pfn
+ z
->spanned_pages
)
3043 && !(pfn
& (pageblock_nr_pages
- 1)))
3044 set_pageblock_migratetype(page
, MIGRATE_MOVABLE
);
3046 INIT_LIST_HEAD(&page
->lru
);
3047 #ifdef WANT_PAGE_VIRTUAL
3048 /* The shift won't overflow because ZONE_NORMAL is below 4G. */
3049 if (!is_highmem_idx(zone
))
3050 set_page_address(page
, __va(pfn
<< PAGE_SHIFT
));
3055 static void __meminit
zone_init_free_lists(struct zone
*zone
)
3058 for_each_migratetype_order(order
, t
) {
3059 INIT_LIST_HEAD(&zone
->free_area
[order
].free_list
[t
]);
3060 zone
->free_area
[order
].nr_free
= 0;
3064 #ifndef __HAVE_ARCH_MEMMAP_INIT
3065 #define memmap_init(size, nid, zone, start_pfn) \
3066 memmap_init_zone((size), (nid), (zone), (start_pfn), MEMMAP_EARLY)
3069 static int zone_batchsize(struct zone
*zone
)
3075 * The per-cpu-pages pools are set to around 1000th of the
3076 * size of the zone. But no more than 1/2 of a meg.
3078 * OK, so we don't know how big the cache is. So guess.
3080 batch
= zone
->present_pages
/ 1024;
3081 if (batch
* PAGE_SIZE
> 512 * 1024)
3082 batch
= (512 * 1024) / PAGE_SIZE
;
3083 batch
/= 4; /* We effectively *= 4 below */
3088 * Clamp the batch to a 2^n - 1 value. Having a power
3089 * of 2 value was found to be more likely to have
3090 * suboptimal cache aliasing properties in some cases.
3092 * For example if 2 tasks are alternately allocating
3093 * batches of pages, one task can end up with a lot
3094 * of pages of one half of the possible page colors
3095 * and the other with pages of the other colors.
3097 batch
= rounddown_pow_of_two(batch
+ batch
/2) - 1;
3102 /* The deferral and batching of frees should be suppressed under NOMMU
3105 * The problem is that NOMMU needs to be able to allocate large chunks
3106 * of contiguous memory as there's no hardware page translation to
3107 * assemble apparent contiguous memory from discontiguous pages.
3109 * Queueing large contiguous runs of pages for batching, however,
3110 * causes the pages to actually be freed in smaller chunks. As there
3111 * can be a significant delay between the individual batches being
3112 * recycled, this leads to the once large chunks of space being
3113 * fragmented and becoming unavailable for high-order allocations.
3119 static void setup_pageset(struct per_cpu_pageset
*p
, unsigned long batch
)
3121 struct per_cpu_pages
*pcp
;
3124 memset(p
, 0, sizeof(*p
));
3128 pcp
->high
= 6 * batch
;
3129 pcp
->batch
= max(1UL, 1 * batch
);
3130 for (migratetype
= 0; migratetype
< MIGRATE_PCPTYPES
; migratetype
++)
3131 INIT_LIST_HEAD(&pcp
->lists
[migratetype
]);
3135 * setup_pagelist_highmark() sets the high water mark for hot per_cpu_pagelist
3136 * to the value high for the pageset p.
3139 static void setup_pagelist_highmark(struct per_cpu_pageset
*p
,
3142 struct per_cpu_pages
*pcp
;
3146 pcp
->batch
= max(1UL, high
/4);
3147 if ((high
/4) > (PAGE_SHIFT
* 8))
3148 pcp
->batch
= PAGE_SHIFT
* 8;
3152 * Allocate per cpu pagesets and initialize them.
3153 * Before this call only boot pagesets were available.
3154 * Boot pagesets will no longer be used by this processorr
3155 * after setup_per_cpu_pageset().
3157 void __init
setup_per_cpu_pageset(void)
3162 for_each_populated_zone(zone
) {
3163 zone
->pageset
= alloc_percpu(struct per_cpu_pageset
);
3165 for_each_possible_cpu(cpu
) {
3166 struct per_cpu_pageset
*pcp
= per_cpu_ptr(zone
->pageset
, cpu
);
3168 setup_pageset(pcp
, zone_batchsize(zone
));
3170 if (percpu_pagelist_fraction
)
3171 setup_pagelist_highmark(pcp
,
3172 (zone
->present_pages
/
3173 percpu_pagelist_fraction
));
3178 static noinline __init_refok
3179 int zone_wait_table_init(struct zone
*zone
, unsigned long zone_size_pages
)
3182 struct pglist_data
*pgdat
= zone
->zone_pgdat
;
3186 * The per-page waitqueue mechanism uses hashed waitqueues
3189 zone
->wait_table_hash_nr_entries
=
3190 wait_table_hash_nr_entries(zone_size_pages
);
3191 zone
->wait_table_bits
=
3192 wait_table_bits(zone
->wait_table_hash_nr_entries
);
3193 alloc_size
= zone
->wait_table_hash_nr_entries
3194 * sizeof(wait_queue_head_t
);
3196 if (!slab_is_available()) {
3197 zone
->wait_table
= (wait_queue_head_t
*)
3198 alloc_bootmem_node(pgdat
, alloc_size
);
3201 * This case means that a zone whose size was 0 gets new memory
3202 * via memory hot-add.
3203 * But it may be the case that a new node was hot-added. In
3204 * this case vmalloc() will not be able to use this new node's
3205 * memory - this wait_table must be initialized to use this new
3206 * node itself as well.
3207 * To use this new node's memory, further consideration will be
3210 zone
->wait_table
= vmalloc(alloc_size
);
3212 if (!zone
->wait_table
)
3215 for(i
= 0; i
< zone
->wait_table_hash_nr_entries
; ++i
)
3216 init_waitqueue_head(zone
->wait_table
+ i
);
3221 static int __zone_pcp_update(void *data
)
3223 struct zone
*zone
= data
;
3225 unsigned long batch
= zone_batchsize(zone
), flags
;
3227 for (cpu
= 0; cpu
< NR_CPUS
; cpu
++) {
3228 struct per_cpu_pageset
*pset
;
3229 struct per_cpu_pages
*pcp
;
3231 pset
= per_cpu_ptr(zone
->pageset
, cpu
);
3234 local_irq_save(flags
);
3235 free_pcppages_bulk(zone
, pcp
->count
, pcp
);
3236 setup_pageset(pset
, batch
);
3237 local_irq_restore(flags
);
3242 void zone_pcp_update(struct zone
*zone
)
3244 stop_machine(__zone_pcp_update
, zone
, NULL
);
3247 static __meminit
void zone_pcp_init(struct zone
*zone
)
3250 * per cpu subsystem is not up at this point. The following code
3251 * relies on the ability of the linker to provide the
3252 * offset of a (static) per cpu variable into the per cpu area.
3254 zone
->pageset
= &boot_pageset
;
3256 if (zone
->present_pages
)
3257 printk(KERN_DEBUG
" %s zone: %lu pages, LIFO batch:%u\n",
3258 zone
->name
, zone
->present_pages
,
3259 zone_batchsize(zone
));
3262 __meminit
int init_currently_empty_zone(struct zone
*zone
,
3263 unsigned long zone_start_pfn
,
3265 enum memmap_context context
)
3267 struct pglist_data
*pgdat
= zone
->zone_pgdat
;
3269 ret
= zone_wait_table_init(zone
, size
);
3272 pgdat
->nr_zones
= zone_idx(zone
) + 1;
3274 zone
->zone_start_pfn
= zone_start_pfn
;
3276 mminit_dprintk(MMINIT_TRACE
, "memmap_init",
3277 "Initialising map node %d zone %lu pfns %lu -> %lu\n",
3279 (unsigned long)zone_idx(zone
),
3280 zone_start_pfn
, (zone_start_pfn
+ size
));
3282 zone_init_free_lists(zone
);
3287 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
3289 * Basic iterator support. Return the first range of PFNs for a node
3290 * Note: nid == MAX_NUMNODES returns first region regardless of node
3292 static int __meminit
first_active_region_index_in_nid(int nid
)
3296 for (i
= 0; i
< nr_nodemap_entries
; i
++)
3297 if (nid
== MAX_NUMNODES
|| early_node_map
[i
].nid
== nid
)
3304 * Basic iterator support. Return the next active range of PFNs for a node
3305 * Note: nid == MAX_NUMNODES returns next region regardless of node
3307 static int __meminit
next_active_region_index_in_nid(int index
, int nid
)
3309 for (index
= index
+ 1; index
< nr_nodemap_entries
; index
++)
3310 if (nid
== MAX_NUMNODES
|| early_node_map
[index
].nid
== nid
)
3316 #ifndef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
3318 * Required by SPARSEMEM. Given a PFN, return what node the PFN is on.
3319 * Architectures may implement their own version but if add_active_range()
3320 * was used and there are no special requirements, this is a convenient
3323 int __meminit
__early_pfn_to_nid(unsigned long pfn
)
3327 for (i
= 0; i
< nr_nodemap_entries
; i
++) {
3328 unsigned long start_pfn
= early_node_map
[i
].start_pfn
;
3329 unsigned long end_pfn
= early_node_map
[i
].end_pfn
;
3331 if (start_pfn
<= pfn
&& pfn
< end_pfn
)
3332 return early_node_map
[i
].nid
;
3334 /* This is a memory hole */
3337 #endif /* CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID */
3339 int __meminit
early_pfn_to_nid(unsigned long pfn
)
3343 nid
= __early_pfn_to_nid(pfn
);
3346 /* just returns 0 */
3350 #ifdef CONFIG_NODES_SPAN_OTHER_NODES
3351 bool __meminit
early_pfn_in_nid(unsigned long pfn
, int node
)
3355 nid
= __early_pfn_to_nid(pfn
);
3356 if (nid
>= 0 && nid
!= node
)
3362 /* Basic iterator support to walk early_node_map[] */
3363 #define for_each_active_range_index_in_nid(i, nid) \
3364 for (i = first_active_region_index_in_nid(nid); i != -1; \
3365 i = next_active_region_index_in_nid(i, nid))
3368 * free_bootmem_with_active_regions - Call free_bootmem_node for each active range
3369 * @nid: The node to free memory on. If MAX_NUMNODES, all nodes are freed.
3370 * @max_low_pfn: The highest PFN that will be passed to free_bootmem_node
3372 * If an architecture guarantees that all ranges registered with
3373 * add_active_ranges() contain no holes and may be freed, this
3374 * this function may be used instead of calling free_bootmem() manually.
3376 void __init
free_bootmem_with_active_regions(int nid
,
3377 unsigned long max_low_pfn
)
3381 for_each_active_range_index_in_nid(i
, nid
) {
3382 unsigned long size_pages
= 0;
3383 unsigned long end_pfn
= early_node_map
[i
].end_pfn
;
3385 if (early_node_map
[i
].start_pfn
>= max_low_pfn
)
3388 if (end_pfn
> max_low_pfn
)
3389 end_pfn
= max_low_pfn
;
3391 size_pages
= end_pfn
- early_node_map
[i
].start_pfn
;
3392 free_bootmem_node(NODE_DATA(early_node_map
[i
].nid
),
3393 PFN_PHYS(early_node_map
[i
].start_pfn
),
3394 size_pages
<< PAGE_SHIFT
);
3398 int __init
add_from_early_node_map(struct range
*range
, int az
,
3399 int nr_range
, int nid
)
3404 /* need to go over early_node_map to find out good range for node */
3405 for_each_active_range_index_in_nid(i
, nid
) {
3406 start
= early_node_map
[i
].start_pfn
;
3407 end
= early_node_map
[i
].end_pfn
;
3408 nr_range
= add_range(range
, az
, nr_range
, start
, end
);
3413 #ifdef CONFIG_NO_BOOTMEM
3414 void * __init
__alloc_memory_core_early(int nid
, u64 size
, u64 align
,
3415 u64 goal
, u64 limit
)
3420 /* need to go over early_node_map to find out good range for node */
3421 for_each_active_range_index_in_nid(i
, nid
) {
3423 u64 ei_start
, ei_last
;
3425 ei_last
= early_node_map
[i
].end_pfn
;
3426 ei_last
<<= PAGE_SHIFT
;
3427 ei_start
= early_node_map
[i
].start_pfn
;
3428 ei_start
<<= PAGE_SHIFT
;
3429 addr
= find_early_area(ei_start
, ei_last
,
3430 goal
, limit
, size
, align
);
3436 printk(KERN_DEBUG
"alloc (nid=%d %llx - %llx) (%llx - %llx) %llx %llx => %llx\n",
3438 ei_start
, ei_last
, goal
, limit
, size
,
3442 ptr
= phys_to_virt(addr
);
3443 memset(ptr
, 0, size
);
3444 reserve_early_without_check(addr
, addr
+ size
, "BOOTMEM");
3453 void __init
work_with_active_regions(int nid
, work_fn_t work_fn
, void *data
)
3458 for_each_active_range_index_in_nid(i
, nid
) {
3459 ret
= work_fn(early_node_map
[i
].start_pfn
,
3460 early_node_map
[i
].end_pfn
, data
);
3466 * sparse_memory_present_with_active_regions - Call memory_present for each active range
3467 * @nid: The node to call memory_present for. If MAX_NUMNODES, all nodes will be used.
3469 * If an architecture guarantees that all ranges registered with
3470 * add_active_ranges() contain no holes and may be freed, this
3471 * function may be used instead of calling memory_present() manually.
3473 void __init
sparse_memory_present_with_active_regions(int nid
)
3477 for_each_active_range_index_in_nid(i
, nid
)
3478 memory_present(early_node_map
[i
].nid
,
3479 early_node_map
[i
].start_pfn
,
3480 early_node_map
[i
].end_pfn
);
3484 * get_pfn_range_for_nid - Return the start and end page frames for a node
3485 * @nid: The nid to return the range for. If MAX_NUMNODES, the min and max PFN are returned.
3486 * @start_pfn: Passed by reference. On return, it will have the node start_pfn.
3487 * @end_pfn: Passed by reference. On return, it will have the node end_pfn.
3489 * It returns the start and end page frame of a node based on information
3490 * provided by an arch calling add_active_range(). If called for a node
3491 * with no available memory, a warning is printed and the start and end
3494 void __meminit
get_pfn_range_for_nid(unsigned int nid
,
3495 unsigned long *start_pfn
, unsigned long *end_pfn
)
3501 for_each_active_range_index_in_nid(i
, nid
) {
3502 *start_pfn
= min(*start_pfn
, early_node_map
[i
].start_pfn
);
3503 *end_pfn
= max(*end_pfn
, early_node_map
[i
].end_pfn
);
3506 if (*start_pfn
== -1UL)
3511 * This finds a zone that can be used for ZONE_MOVABLE pages. The
3512 * assumption is made that zones within a node are ordered in monotonic
3513 * increasing memory addresses so that the "highest" populated zone is used
3515 static void __init
find_usable_zone_for_movable(void)
3518 for (zone_index
= MAX_NR_ZONES
- 1; zone_index
>= 0; zone_index
--) {
3519 if (zone_index
== ZONE_MOVABLE
)
3522 if (arch_zone_highest_possible_pfn
[zone_index
] >
3523 arch_zone_lowest_possible_pfn
[zone_index
])
3527 VM_BUG_ON(zone_index
== -1);
3528 movable_zone
= zone_index
;
3532 * The zone ranges provided by the architecture do not include ZONE_MOVABLE
3533 * because it is sized independant of architecture. Unlike the other zones,
3534 * the starting point for ZONE_MOVABLE is not fixed. It may be different
3535 * in each node depending on the size of each node and how evenly kernelcore
3536 * is distributed. This helper function adjusts the zone ranges
3537 * provided by the architecture for a given node by using the end of the
3538 * highest usable zone for ZONE_MOVABLE. This preserves the assumption that
3539 * zones within a node are in order of monotonic increases memory addresses
3541 static void __meminit
adjust_zone_range_for_zone_movable(int nid
,
3542 unsigned long zone_type
,
3543 unsigned long node_start_pfn
,
3544 unsigned long node_end_pfn
,
3545 unsigned long *zone_start_pfn
,
3546 unsigned long *zone_end_pfn
)
3548 /* Only adjust if ZONE_MOVABLE is on this node */
3549 if (zone_movable_pfn
[nid
]) {
3550 /* Size ZONE_MOVABLE */
3551 if (zone_type
== ZONE_MOVABLE
) {
3552 *zone_start_pfn
= zone_movable_pfn
[nid
];
3553 *zone_end_pfn
= min(node_end_pfn
,
3554 arch_zone_highest_possible_pfn
[movable_zone
]);
3556 /* Adjust for ZONE_MOVABLE starting within this range */
3557 } else if (*zone_start_pfn
< zone_movable_pfn
[nid
] &&
3558 *zone_end_pfn
> zone_movable_pfn
[nid
]) {
3559 *zone_end_pfn
= zone_movable_pfn
[nid
];
3561 /* Check if this whole range is within ZONE_MOVABLE */
3562 } else if (*zone_start_pfn
>= zone_movable_pfn
[nid
])
3563 *zone_start_pfn
= *zone_end_pfn
;
3568 * Return the number of pages a zone spans in a node, including holes
3569 * present_pages = zone_spanned_pages_in_node() - zone_absent_pages_in_node()
3571 static unsigned long __meminit
zone_spanned_pages_in_node(int nid
,
3572 unsigned long zone_type
,
3573 unsigned long *ignored
)
3575 unsigned long node_start_pfn
, node_end_pfn
;
3576 unsigned long zone_start_pfn
, zone_end_pfn
;
3578 /* Get the start and end of the node and zone */
3579 get_pfn_range_for_nid(nid
, &node_start_pfn
, &node_end_pfn
);
3580 zone_start_pfn
= arch_zone_lowest_possible_pfn
[zone_type
];
3581 zone_end_pfn
= arch_zone_highest_possible_pfn
[zone_type
];
3582 adjust_zone_range_for_zone_movable(nid
, zone_type
,
3583 node_start_pfn
, node_end_pfn
,
3584 &zone_start_pfn
, &zone_end_pfn
);
3586 /* Check that this node has pages within the zone's required range */
3587 if (zone_end_pfn
< node_start_pfn
|| zone_start_pfn
> node_end_pfn
)
3590 /* Move the zone boundaries inside the node if necessary */
3591 zone_end_pfn
= min(zone_end_pfn
, node_end_pfn
);
3592 zone_start_pfn
= max(zone_start_pfn
, node_start_pfn
);
3594 /* Return the spanned pages */
3595 return zone_end_pfn
- zone_start_pfn
;
3599 * Return the number of holes in a range on a node. If nid is MAX_NUMNODES,
3600 * then all holes in the requested range will be accounted for.
3602 unsigned long __meminit
__absent_pages_in_range(int nid
,
3603 unsigned long range_start_pfn
,
3604 unsigned long range_end_pfn
)
3607 unsigned long prev_end_pfn
= 0, hole_pages
= 0;
3608 unsigned long start_pfn
;
3610 /* Find the end_pfn of the first active range of pfns in the node */
3611 i
= first_active_region_index_in_nid(nid
);
3615 prev_end_pfn
= min(early_node_map
[i
].start_pfn
, range_end_pfn
);
3617 /* Account for ranges before physical memory on this node */
3618 if (early_node_map
[i
].start_pfn
> range_start_pfn
)
3619 hole_pages
= prev_end_pfn
- range_start_pfn
;
3621 /* Find all holes for the zone within the node */
3622 for (; i
!= -1; i
= next_active_region_index_in_nid(i
, nid
)) {
3624 /* No need to continue if prev_end_pfn is outside the zone */
3625 if (prev_end_pfn
>= range_end_pfn
)
3628 /* Make sure the end of the zone is not within the hole */
3629 start_pfn
= min(early_node_map
[i
].start_pfn
, range_end_pfn
);
3630 prev_end_pfn
= max(prev_end_pfn
, range_start_pfn
);
3632 /* Update the hole size cound and move on */
3633 if (start_pfn
> range_start_pfn
) {
3634 BUG_ON(prev_end_pfn
> start_pfn
);
3635 hole_pages
+= start_pfn
- prev_end_pfn
;
3637 prev_end_pfn
= early_node_map
[i
].end_pfn
;
3640 /* Account for ranges past physical memory on this node */
3641 if (range_end_pfn
> prev_end_pfn
)
3642 hole_pages
+= range_end_pfn
-
3643 max(range_start_pfn
, prev_end_pfn
);
3649 * absent_pages_in_range - Return number of page frames in holes within a range
3650 * @start_pfn: The start PFN to start searching for holes
3651 * @end_pfn: The end PFN to stop searching for holes
3653 * It returns the number of pages frames in memory holes within a range.
3655 unsigned long __init
absent_pages_in_range(unsigned long start_pfn
,
3656 unsigned long end_pfn
)
3658 return __absent_pages_in_range(MAX_NUMNODES
, start_pfn
, end_pfn
);
3661 /* Return the number of page frames in holes in a zone on a node */
3662 static unsigned long __meminit
zone_absent_pages_in_node(int nid
,
3663 unsigned long zone_type
,
3664 unsigned long *ignored
)
3666 unsigned long node_start_pfn
, node_end_pfn
;
3667 unsigned long zone_start_pfn
, zone_end_pfn
;
3669 get_pfn_range_for_nid(nid
, &node_start_pfn
, &node_end_pfn
);
3670 zone_start_pfn
= max(arch_zone_lowest_possible_pfn
[zone_type
],
3672 zone_end_pfn
= min(arch_zone_highest_possible_pfn
[zone_type
],
3675 adjust_zone_range_for_zone_movable(nid
, zone_type
,
3676 node_start_pfn
, node_end_pfn
,
3677 &zone_start_pfn
, &zone_end_pfn
);
3678 return __absent_pages_in_range(nid
, zone_start_pfn
, zone_end_pfn
);
3682 static inline unsigned long __meminit
zone_spanned_pages_in_node(int nid
,
3683 unsigned long zone_type
,
3684 unsigned long *zones_size
)
3686 return zones_size
[zone_type
];
3689 static inline unsigned long __meminit
zone_absent_pages_in_node(int nid
,
3690 unsigned long zone_type
,
3691 unsigned long *zholes_size
)
3696 return zholes_size
[zone_type
];
3701 static void __meminit
calculate_node_totalpages(struct pglist_data
*pgdat
,
3702 unsigned long *zones_size
, unsigned long *zholes_size
)
3704 unsigned long realtotalpages
, totalpages
= 0;
3707 for (i
= 0; i
< MAX_NR_ZONES
; i
++)
3708 totalpages
+= zone_spanned_pages_in_node(pgdat
->node_id
, i
,
3710 pgdat
->node_spanned_pages
= totalpages
;
3712 realtotalpages
= totalpages
;
3713 for (i
= 0; i
< MAX_NR_ZONES
; i
++)
3715 zone_absent_pages_in_node(pgdat
->node_id
, i
,
3717 pgdat
->node_present_pages
= realtotalpages
;
3718 printk(KERN_DEBUG
"On node %d totalpages: %lu\n", pgdat
->node_id
,
3722 #ifndef CONFIG_SPARSEMEM
3724 * Calculate the size of the zone->blockflags rounded to an unsigned long
3725 * Start by making sure zonesize is a multiple of pageblock_order by rounding
3726 * up. Then use 1 NR_PAGEBLOCK_BITS worth of bits per pageblock, finally
3727 * round what is now in bits to nearest long in bits, then return it in
3730 static unsigned long __init
usemap_size(unsigned long zonesize
)
3732 unsigned long usemapsize
;
3734 usemapsize
= roundup(zonesize
, pageblock_nr_pages
);
3735 usemapsize
= usemapsize
>> pageblock_order
;
3736 usemapsize
*= NR_PAGEBLOCK_BITS
;
3737 usemapsize
= roundup(usemapsize
, 8 * sizeof(unsigned long));
3739 return usemapsize
/ 8;
3742 static void __init
setup_usemap(struct pglist_data
*pgdat
,
3743 struct zone
*zone
, unsigned long zonesize
)
3745 unsigned long usemapsize
= usemap_size(zonesize
);
3746 zone
->pageblock_flags
= NULL
;
3748 zone
->pageblock_flags
= alloc_bootmem_node(pgdat
, usemapsize
);
3751 static void inline setup_usemap(struct pglist_data
*pgdat
,
3752 struct zone
*zone
, unsigned long zonesize
) {}
3753 #endif /* CONFIG_SPARSEMEM */
3755 #ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
3757 /* Return a sensible default order for the pageblock size. */
3758 static inline int pageblock_default_order(void)
3760 if (HPAGE_SHIFT
> PAGE_SHIFT
)
3761 return HUGETLB_PAGE_ORDER
;
3766 /* Initialise the number of pages represented by NR_PAGEBLOCK_BITS */
3767 static inline void __init
set_pageblock_order(unsigned int order
)
3769 /* Check that pageblock_nr_pages has not already been setup */
3770 if (pageblock_order
)
3774 * Assume the largest contiguous order of interest is a huge page.
3775 * This value may be variable depending on boot parameters on IA64
3777 pageblock_order
= order
;
3779 #else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
3782 * When CONFIG_HUGETLB_PAGE_SIZE_VARIABLE is not set, set_pageblock_order()
3783 * and pageblock_default_order() are unused as pageblock_order is set
3784 * at compile-time. See include/linux/pageblock-flags.h for the values of
3785 * pageblock_order based on the kernel config
3787 static inline int pageblock_default_order(unsigned int order
)
3791 #define set_pageblock_order(x) do {} while (0)
3793 #endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
3796 * Set up the zone data structures:
3797 * - mark all pages reserved
3798 * - mark all memory queues empty
3799 * - clear the memory bitmaps
3801 static void __paginginit
free_area_init_core(struct pglist_data
*pgdat
,
3802 unsigned long *zones_size
, unsigned long *zholes_size
)
3805 int nid
= pgdat
->node_id
;
3806 unsigned long zone_start_pfn
= pgdat
->node_start_pfn
;
3809 pgdat_resize_init(pgdat
);
3810 pgdat
->nr_zones
= 0;
3811 init_waitqueue_head(&pgdat
->kswapd_wait
);
3812 pgdat
->kswapd_max_order
= 0;
3813 pgdat_page_cgroup_init(pgdat
);
3815 for (j
= 0; j
< MAX_NR_ZONES
; j
++) {
3816 struct zone
*zone
= pgdat
->node_zones
+ j
;
3817 unsigned long size
, realsize
, memmap_pages
;
3820 size
= zone_spanned_pages_in_node(nid
, j
, zones_size
);
3821 realsize
= size
- zone_absent_pages_in_node(nid
, j
,
3825 * Adjust realsize so that it accounts for how much memory
3826 * is used by this zone for memmap. This affects the watermark
3827 * and per-cpu initialisations
3830 PAGE_ALIGN(size
* sizeof(struct page
)) >> PAGE_SHIFT
;
3831 if (realsize
>= memmap_pages
) {
3832 realsize
-= memmap_pages
;
3835 " %s zone: %lu pages used for memmap\n",
3836 zone_names
[j
], memmap_pages
);
3839 " %s zone: %lu pages exceeds realsize %lu\n",
3840 zone_names
[j
], memmap_pages
, realsize
);
3842 /* Account for reserved pages */
3843 if (j
== 0 && realsize
> dma_reserve
) {
3844 realsize
-= dma_reserve
;
3845 printk(KERN_DEBUG
" %s zone: %lu pages reserved\n",
3846 zone_names
[0], dma_reserve
);
3849 if (!is_highmem_idx(j
))
3850 nr_kernel_pages
+= realsize
;
3851 nr_all_pages
+= realsize
;
3853 zone
->spanned_pages
= size
;
3854 zone
->present_pages
= realsize
;
3857 zone
->min_unmapped_pages
= (realsize
*sysctl_min_unmapped_ratio
)
3859 zone
->min_slab_pages
= (realsize
* sysctl_min_slab_ratio
) / 100;
3861 zone
->name
= zone_names
[j
];
3862 spin_lock_init(&zone
->lock
);
3863 spin_lock_init(&zone
->lru_lock
);
3864 zone_seqlock_init(zone
);
3865 zone
->zone_pgdat
= pgdat
;
3867 zone
->prev_priority
= DEF_PRIORITY
;
3869 zone_pcp_init(zone
);
3871 INIT_LIST_HEAD(&zone
->lru
[l
].list
);
3872 zone
->reclaim_stat
.nr_saved_scan
[l
] = 0;
3874 zone
->reclaim_stat
.recent_rotated
[0] = 0;
3875 zone
->reclaim_stat
.recent_rotated
[1] = 0;
3876 zone
->reclaim_stat
.recent_scanned
[0] = 0;
3877 zone
->reclaim_stat
.recent_scanned
[1] = 0;
3878 zap_zone_vm_stats(zone
);
3883 set_pageblock_order(pageblock_default_order());
3884 setup_usemap(pgdat
, zone
, size
);
3885 ret
= init_currently_empty_zone(zone
, zone_start_pfn
,
3886 size
, MEMMAP_EARLY
);
3888 memmap_init(size
, nid
, j
, zone_start_pfn
);
3889 zone_start_pfn
+= size
;
3893 static void __init_refok
alloc_node_mem_map(struct pglist_data
*pgdat
)
3895 /* Skip empty nodes */
3896 if (!pgdat
->node_spanned_pages
)
3899 #ifdef CONFIG_FLAT_NODE_MEM_MAP
3900 /* ia64 gets its own node_mem_map, before this, without bootmem */
3901 if (!pgdat
->node_mem_map
) {
3902 unsigned long size
, start
, end
;
3906 * The zone's endpoints aren't required to be MAX_ORDER
3907 * aligned but the node_mem_map endpoints must be in order
3908 * for the buddy allocator to function correctly.
3910 start
= pgdat
->node_start_pfn
& ~(MAX_ORDER_NR_PAGES
- 1);
3911 end
= pgdat
->node_start_pfn
+ pgdat
->node_spanned_pages
;
3912 end
= ALIGN(end
, MAX_ORDER_NR_PAGES
);
3913 size
= (end
- start
) * sizeof(struct page
);
3914 map
= alloc_remap(pgdat
->node_id
, size
);
3916 map
= alloc_bootmem_node(pgdat
, size
);
3917 pgdat
->node_mem_map
= map
+ (pgdat
->node_start_pfn
- start
);
3919 #ifndef CONFIG_NEED_MULTIPLE_NODES
3921 * With no DISCONTIG, the global mem_map is just set as node 0's
3923 if (pgdat
== NODE_DATA(0)) {
3924 mem_map
= NODE_DATA(0)->node_mem_map
;
3925 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
3926 if (page_to_pfn(mem_map
) != pgdat
->node_start_pfn
)
3927 mem_map
-= (pgdat
->node_start_pfn
- ARCH_PFN_OFFSET
);
3928 #endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
3931 #endif /* CONFIG_FLAT_NODE_MEM_MAP */
3934 void __paginginit
free_area_init_node(int nid
, unsigned long *zones_size
,
3935 unsigned long node_start_pfn
, unsigned long *zholes_size
)
3937 pg_data_t
*pgdat
= NODE_DATA(nid
);
3939 pgdat
->node_id
= nid
;
3940 pgdat
->node_start_pfn
= node_start_pfn
;
3941 calculate_node_totalpages(pgdat
, zones_size
, zholes_size
);
3943 alloc_node_mem_map(pgdat
);
3944 #ifdef CONFIG_FLAT_NODE_MEM_MAP
3945 printk(KERN_DEBUG
"free_area_init_node: node %d, pgdat %08lx, node_mem_map %08lx\n",
3946 nid
, (unsigned long)pgdat
,
3947 (unsigned long)pgdat
->node_mem_map
);
3950 free_area_init_core(pgdat
, zones_size
, zholes_size
);
3953 #ifdef CONFIG_ARCH_POPULATES_NODE_MAP
3955 #if MAX_NUMNODES > 1
3957 * Figure out the number of possible node ids.
3959 static void __init
setup_nr_node_ids(void)
3962 unsigned int highest
= 0;
3964 for_each_node_mask(node
, node_possible_map
)
3966 nr_node_ids
= highest
+ 1;
3969 static inline void setup_nr_node_ids(void)
3975 * add_active_range - Register a range of PFNs backed by physical memory
3976 * @nid: The node ID the range resides on
3977 * @start_pfn: The start PFN of the available physical memory
3978 * @end_pfn: The end PFN of the available physical memory
3980 * These ranges are stored in an early_node_map[] and later used by
3981 * free_area_init_nodes() to calculate zone sizes and holes. If the
3982 * range spans a memory hole, it is up to the architecture to ensure
3983 * the memory is not freed by the bootmem allocator. If possible
3984 * the range being registered will be merged with existing ranges.
3986 void __init
add_active_range(unsigned int nid
, unsigned long start_pfn
,
3987 unsigned long end_pfn
)
3991 mminit_dprintk(MMINIT_TRACE
, "memory_register",
3992 "Entering add_active_range(%d, %#lx, %#lx) "
3993 "%d entries of %d used\n",
3994 nid
, start_pfn
, end_pfn
,
3995 nr_nodemap_entries
, MAX_ACTIVE_REGIONS
);
3997 mminit_validate_memmodel_limits(&start_pfn
, &end_pfn
);
3999 /* Merge with existing active regions if possible */
4000 for (i
= 0; i
< nr_nodemap_entries
; i
++) {
4001 if (early_node_map
[i
].nid
!= nid
)
4004 /* Skip if an existing region covers this new one */
4005 if (start_pfn
>= early_node_map
[i
].start_pfn
&&
4006 end_pfn
<= early_node_map
[i
].end_pfn
)
4009 /* Merge forward if suitable */
4010 if (start_pfn
<= early_node_map
[i
].end_pfn
&&
4011 end_pfn
> early_node_map
[i
].end_pfn
) {
4012 early_node_map
[i
].end_pfn
= end_pfn
;
4016 /* Merge backward if suitable */
4017 if (start_pfn
< early_node_map
[i
].start_pfn
&&
4018 end_pfn
>= early_node_map
[i
].start_pfn
) {
4019 early_node_map
[i
].start_pfn
= start_pfn
;
4024 /* Check that early_node_map is large enough */
4025 if (i
>= MAX_ACTIVE_REGIONS
) {
4026 printk(KERN_CRIT
"More than %d memory regions, truncating\n",
4027 MAX_ACTIVE_REGIONS
);
4031 early_node_map
[i
].nid
= nid
;
4032 early_node_map
[i
].start_pfn
= start_pfn
;
4033 early_node_map
[i
].end_pfn
= end_pfn
;
4034 nr_nodemap_entries
= i
+ 1;
4038 * remove_active_range - Shrink an existing registered range of PFNs
4039 * @nid: The node id the range is on that should be shrunk
4040 * @start_pfn: The new PFN of the range
4041 * @end_pfn: The new PFN of the range
4043 * i386 with NUMA use alloc_remap() to store a node_mem_map on a local node.
4044 * The map is kept near the end physical page range that has already been
4045 * registered. This function allows an arch to shrink an existing registered
4048 void __init
remove_active_range(unsigned int nid
, unsigned long start_pfn
,
4049 unsigned long end_pfn
)
4054 printk(KERN_DEBUG
"remove_active_range (%d, %lu, %lu)\n",
4055 nid
, start_pfn
, end_pfn
);
4057 /* Find the old active region end and shrink */
4058 for_each_active_range_index_in_nid(i
, nid
) {
4059 if (early_node_map
[i
].start_pfn
>= start_pfn
&&
4060 early_node_map
[i
].end_pfn
<= end_pfn
) {
4062 early_node_map
[i
].start_pfn
= 0;
4063 early_node_map
[i
].end_pfn
= 0;
4067 if (early_node_map
[i
].start_pfn
< start_pfn
&&
4068 early_node_map
[i
].end_pfn
> start_pfn
) {
4069 unsigned long temp_end_pfn
= early_node_map
[i
].end_pfn
;
4070 early_node_map
[i
].end_pfn
= start_pfn
;
4071 if (temp_end_pfn
> end_pfn
)
4072 add_active_range(nid
, end_pfn
, temp_end_pfn
);
4075 if (early_node_map
[i
].start_pfn
>= start_pfn
&&
4076 early_node_map
[i
].end_pfn
> end_pfn
&&
4077 early_node_map
[i
].start_pfn
< end_pfn
) {
4078 early_node_map
[i
].start_pfn
= end_pfn
;
4086 /* remove the blank ones */
4087 for (i
= nr_nodemap_entries
- 1; i
> 0; i
--) {
4088 if (early_node_map
[i
].nid
!= nid
)
4090 if (early_node_map
[i
].end_pfn
)
4092 /* we found it, get rid of it */
4093 for (j
= i
; j
< nr_nodemap_entries
- 1; j
++)
4094 memcpy(&early_node_map
[j
], &early_node_map
[j
+1],
4095 sizeof(early_node_map
[j
]));
4096 j
= nr_nodemap_entries
- 1;
4097 memset(&early_node_map
[j
], 0, sizeof(early_node_map
[j
]));
4098 nr_nodemap_entries
--;
4103 * remove_all_active_ranges - Remove all currently registered regions
4105 * During discovery, it may be found that a table like SRAT is invalid
4106 * and an alternative discovery method must be used. This function removes
4107 * all currently registered regions.
4109 void __init
remove_all_active_ranges(void)
4111 memset(early_node_map
, 0, sizeof(early_node_map
));
4112 nr_nodemap_entries
= 0;
4115 /* Compare two active node_active_regions */
4116 static int __init
cmp_node_active_region(const void *a
, const void *b
)
4118 struct node_active_region
*arange
= (struct node_active_region
*)a
;
4119 struct node_active_region
*brange
= (struct node_active_region
*)b
;
4121 /* Done this way to avoid overflows */
4122 if (arange
->start_pfn
> brange
->start_pfn
)
4124 if (arange
->start_pfn
< brange
->start_pfn
)
4130 /* sort the node_map by start_pfn */
4131 void __init
sort_node_map(void)
4133 sort(early_node_map
, (size_t)nr_nodemap_entries
,
4134 sizeof(struct node_active_region
),
4135 cmp_node_active_region
, NULL
);
4138 /* Find the lowest pfn for a node */
4139 static unsigned long __init
find_min_pfn_for_node(int nid
)
4142 unsigned long min_pfn
= ULONG_MAX
;
4144 /* Assuming a sorted map, the first range found has the starting pfn */
4145 for_each_active_range_index_in_nid(i
, nid
)
4146 min_pfn
= min(min_pfn
, early_node_map
[i
].start_pfn
);
4148 if (min_pfn
== ULONG_MAX
) {
4150 "Could not find start_pfn for node %d\n", nid
);
4158 * find_min_pfn_with_active_regions - Find the minimum PFN registered
4160 * It returns the minimum PFN based on information provided via
4161 * add_active_range().
4163 unsigned long __init
find_min_pfn_with_active_regions(void)
4165 return find_min_pfn_for_node(MAX_NUMNODES
);
4169 * early_calculate_totalpages()
4170 * Sum pages in active regions for movable zone.
4171 * Populate N_HIGH_MEMORY for calculating usable_nodes.
4173 static unsigned long __init
early_calculate_totalpages(void)
4176 unsigned long totalpages
= 0;
4178 for (i
= 0; i
< nr_nodemap_entries
; i
++) {
4179 unsigned long pages
= early_node_map
[i
].end_pfn
-
4180 early_node_map
[i
].start_pfn
;
4181 totalpages
+= pages
;
4183 node_set_state(early_node_map
[i
].nid
, N_HIGH_MEMORY
);
4189 * Find the PFN the Movable zone begins in each node. Kernel memory
4190 * is spread evenly between nodes as long as the nodes have enough
4191 * memory. When they don't, some nodes will have more kernelcore than
4194 static void __init
find_zone_movable_pfns_for_nodes(unsigned long *movable_pfn
)
4197 unsigned long usable_startpfn
;
4198 unsigned long kernelcore_node
, kernelcore_remaining
;
4199 /* save the state before borrow the nodemask */
4200 nodemask_t saved_node_state
= node_states
[N_HIGH_MEMORY
];
4201 unsigned long totalpages
= early_calculate_totalpages();
4202 int usable_nodes
= nodes_weight(node_states
[N_HIGH_MEMORY
]);
4205 * If movablecore was specified, calculate what size of
4206 * kernelcore that corresponds so that memory usable for
4207 * any allocation type is evenly spread. If both kernelcore
4208 * and movablecore are specified, then the value of kernelcore
4209 * will be used for required_kernelcore if it's greater than
4210 * what movablecore would have allowed.
4212 if (required_movablecore
) {
4213 unsigned long corepages
;
4216 * Round-up so that ZONE_MOVABLE is at least as large as what
4217 * was requested by the user
4219 required_movablecore
=
4220 roundup(required_movablecore
, MAX_ORDER_NR_PAGES
);
4221 corepages
= totalpages
- required_movablecore
;
4223 required_kernelcore
= max(required_kernelcore
, corepages
);
4226 /* If kernelcore was not specified, there is no ZONE_MOVABLE */
4227 if (!required_kernelcore
)
4230 /* usable_startpfn is the lowest possible pfn ZONE_MOVABLE can be at */
4231 find_usable_zone_for_movable();
4232 usable_startpfn
= arch_zone_lowest_possible_pfn
[movable_zone
];
4235 /* Spread kernelcore memory as evenly as possible throughout nodes */
4236 kernelcore_node
= required_kernelcore
/ usable_nodes
;
4237 for_each_node_state(nid
, N_HIGH_MEMORY
) {
4239 * Recalculate kernelcore_node if the division per node
4240 * now exceeds what is necessary to satisfy the requested
4241 * amount of memory for the kernel
4243 if (required_kernelcore
< kernelcore_node
)
4244 kernelcore_node
= required_kernelcore
/ usable_nodes
;
4247 * As the map is walked, we track how much memory is usable
4248 * by the kernel using kernelcore_remaining. When it is
4249 * 0, the rest of the node is usable by ZONE_MOVABLE
4251 kernelcore_remaining
= kernelcore_node
;
4253 /* Go through each range of PFNs within this node */
4254 for_each_active_range_index_in_nid(i
, nid
) {
4255 unsigned long start_pfn
, end_pfn
;
4256 unsigned long size_pages
;
4258 start_pfn
= max(early_node_map
[i
].start_pfn
,
4259 zone_movable_pfn
[nid
]);
4260 end_pfn
= early_node_map
[i
].end_pfn
;
4261 if (start_pfn
>= end_pfn
)
4264 /* Account for what is only usable for kernelcore */
4265 if (start_pfn
< usable_startpfn
) {
4266 unsigned long kernel_pages
;
4267 kernel_pages
= min(end_pfn
, usable_startpfn
)
4270 kernelcore_remaining
-= min(kernel_pages
,
4271 kernelcore_remaining
);
4272 required_kernelcore
-= min(kernel_pages
,
4273 required_kernelcore
);
4275 /* Continue if range is now fully accounted */
4276 if (end_pfn
<= usable_startpfn
) {
4279 * Push zone_movable_pfn to the end so
4280 * that if we have to rebalance
4281 * kernelcore across nodes, we will
4282 * not double account here
4284 zone_movable_pfn
[nid
] = end_pfn
;
4287 start_pfn
= usable_startpfn
;
4291 * The usable PFN range for ZONE_MOVABLE is from
4292 * start_pfn->end_pfn. Calculate size_pages as the
4293 * number of pages used as kernelcore
4295 size_pages
= end_pfn
- start_pfn
;
4296 if (size_pages
> kernelcore_remaining
)
4297 size_pages
= kernelcore_remaining
;
4298 zone_movable_pfn
[nid
] = start_pfn
+ size_pages
;
4301 * Some kernelcore has been met, update counts and
4302 * break if the kernelcore for this node has been
4305 required_kernelcore
-= min(required_kernelcore
,
4307 kernelcore_remaining
-= size_pages
;
4308 if (!kernelcore_remaining
)
4314 * If there is still required_kernelcore, we do another pass with one
4315 * less node in the count. This will push zone_movable_pfn[nid] further
4316 * along on the nodes that still have memory until kernelcore is
4320 if (usable_nodes
&& required_kernelcore
> usable_nodes
)
4323 /* Align start of ZONE_MOVABLE on all nids to MAX_ORDER_NR_PAGES */
4324 for (nid
= 0; nid
< MAX_NUMNODES
; nid
++)
4325 zone_movable_pfn
[nid
] =
4326 roundup(zone_movable_pfn
[nid
], MAX_ORDER_NR_PAGES
);
4329 /* restore the node_state */
4330 node_states
[N_HIGH_MEMORY
] = saved_node_state
;
4333 /* Any regular memory on that node ? */
4334 static void check_for_regular_memory(pg_data_t
*pgdat
)
4336 #ifdef CONFIG_HIGHMEM
4337 enum zone_type zone_type
;
4339 for (zone_type
= 0; zone_type
<= ZONE_NORMAL
; zone_type
++) {
4340 struct zone
*zone
= &pgdat
->node_zones
[zone_type
];
4341 if (zone
->present_pages
)
4342 node_set_state(zone_to_nid(zone
), N_NORMAL_MEMORY
);
4348 * free_area_init_nodes - Initialise all pg_data_t and zone data
4349 * @max_zone_pfn: an array of max PFNs for each zone
4351 * This will call free_area_init_node() for each active node in the system.
4352 * Using the page ranges provided by add_active_range(), the size of each
4353 * zone in each node and their holes is calculated. If the maximum PFN
4354 * between two adjacent zones match, it is assumed that the zone is empty.
4355 * For example, if arch_max_dma_pfn == arch_max_dma32_pfn, it is assumed
4356 * that arch_max_dma32_pfn has no pages. It is also assumed that a zone
4357 * starts where the previous one ended. For example, ZONE_DMA32 starts
4358 * at arch_max_dma_pfn.
4360 void __init
free_area_init_nodes(unsigned long *max_zone_pfn
)
4365 /* Sort early_node_map as initialisation assumes it is sorted */
4368 /* Record where the zone boundaries are */
4369 memset(arch_zone_lowest_possible_pfn
, 0,
4370 sizeof(arch_zone_lowest_possible_pfn
));
4371 memset(arch_zone_highest_possible_pfn
, 0,
4372 sizeof(arch_zone_highest_possible_pfn
));
4373 arch_zone_lowest_possible_pfn
[0] = find_min_pfn_with_active_regions();
4374 arch_zone_highest_possible_pfn
[0] = max_zone_pfn
[0];
4375 for (i
= 1; i
< MAX_NR_ZONES
; i
++) {
4376 if (i
== ZONE_MOVABLE
)
4378 arch_zone_lowest_possible_pfn
[i
] =
4379 arch_zone_highest_possible_pfn
[i
-1];
4380 arch_zone_highest_possible_pfn
[i
] =
4381 max(max_zone_pfn
[i
], arch_zone_lowest_possible_pfn
[i
]);
4383 arch_zone_lowest_possible_pfn
[ZONE_MOVABLE
] = 0;
4384 arch_zone_highest_possible_pfn
[ZONE_MOVABLE
] = 0;
4386 /* Find the PFNs that ZONE_MOVABLE begins at in each node */
4387 memset(zone_movable_pfn
, 0, sizeof(zone_movable_pfn
));
4388 find_zone_movable_pfns_for_nodes(zone_movable_pfn
);
4390 /* Print out the zone ranges */
4391 printk("Zone PFN ranges:\n");
4392 for (i
= 0; i
< MAX_NR_ZONES
; i
++) {
4393 if (i
== ZONE_MOVABLE
)
4395 printk(" %-8s ", zone_names
[i
]);
4396 if (arch_zone_lowest_possible_pfn
[i
] ==
4397 arch_zone_highest_possible_pfn
[i
])
4400 printk("%0#10lx -> %0#10lx\n",
4401 arch_zone_lowest_possible_pfn
[i
],
4402 arch_zone_highest_possible_pfn
[i
]);
4405 /* Print out the PFNs ZONE_MOVABLE begins at in each node */
4406 printk("Movable zone start PFN for each node\n");
4407 for (i
= 0; i
< MAX_NUMNODES
; i
++) {
4408 if (zone_movable_pfn
[i
])
4409 printk(" Node %d: %lu\n", i
, zone_movable_pfn
[i
]);
4412 /* Print out the early_node_map[] */
4413 printk("early_node_map[%d] active PFN ranges\n", nr_nodemap_entries
);
4414 for (i
= 0; i
< nr_nodemap_entries
; i
++)
4415 printk(" %3d: %0#10lx -> %0#10lx\n", early_node_map
[i
].nid
,
4416 early_node_map
[i
].start_pfn
,
4417 early_node_map
[i
].end_pfn
);
4419 /* Initialise every node */
4420 mminit_verify_pageflags_layout();
4421 setup_nr_node_ids();
4422 for_each_online_node(nid
) {
4423 pg_data_t
*pgdat
= NODE_DATA(nid
);
4424 free_area_init_node(nid
, NULL
,
4425 find_min_pfn_for_node(nid
), NULL
);
4427 /* Any memory on that node */
4428 if (pgdat
->node_present_pages
)
4429 node_set_state(nid
, N_HIGH_MEMORY
);
4430 check_for_regular_memory(pgdat
);
4434 static int __init
cmdline_parse_core(char *p
, unsigned long *core
)
4436 unsigned long long coremem
;
4440 coremem
= memparse(p
, &p
);
4441 *core
= coremem
>> PAGE_SHIFT
;
4443 /* Paranoid check that UL is enough for the coremem value */
4444 WARN_ON((coremem
>> PAGE_SHIFT
) > ULONG_MAX
);
4450 * kernelcore=size sets the amount of memory for use for allocations that
4451 * cannot be reclaimed or migrated.
4453 static int __init
cmdline_parse_kernelcore(char *p
)
4455 return cmdline_parse_core(p
, &required_kernelcore
);
4459 * movablecore=size sets the amount of memory for use for allocations that
4460 * can be reclaimed or migrated.
4462 static int __init
cmdline_parse_movablecore(char *p
)
4464 return cmdline_parse_core(p
, &required_movablecore
);
4467 early_param("kernelcore", cmdline_parse_kernelcore
);
4468 early_param("movablecore", cmdline_parse_movablecore
);
4470 #endif /* CONFIG_ARCH_POPULATES_NODE_MAP */
4473 * set_dma_reserve - set the specified number of pages reserved in the first zone
4474 * @new_dma_reserve: The number of pages to mark reserved
4476 * The per-cpu batchsize and zone watermarks are determined by present_pages.
4477 * In the DMA zone, a significant percentage may be consumed by kernel image
4478 * and other unfreeable allocations which can skew the watermarks badly. This
4479 * function may optionally be used to account for unfreeable pages in the
4480 * first zone (e.g., ZONE_DMA). The effect will be lower watermarks and
4481 * smaller per-cpu batchsize.
4483 void __init
set_dma_reserve(unsigned long new_dma_reserve
)
4485 dma_reserve
= new_dma_reserve
;
4488 #ifndef CONFIG_NEED_MULTIPLE_NODES
4489 struct pglist_data __refdata contig_page_data
= {
4490 #ifndef CONFIG_NO_BOOTMEM
4491 .bdata
= &bootmem_node_data
[0]
4494 EXPORT_SYMBOL(contig_page_data
);
4497 void __init
free_area_init(unsigned long *zones_size
)
4499 free_area_init_node(0, zones_size
,
4500 __pa(PAGE_OFFSET
) >> PAGE_SHIFT
, NULL
);
4503 static int page_alloc_cpu_notify(struct notifier_block
*self
,
4504 unsigned long action
, void *hcpu
)
4506 int cpu
= (unsigned long)hcpu
;
4508 if (action
== CPU_DEAD
|| action
== CPU_DEAD_FROZEN
) {
4512 * Spill the event counters of the dead processor
4513 * into the current processors event counters.
4514 * This artificially elevates the count of the current
4517 vm_events_fold_cpu(cpu
);
4520 * Zero the differential counters of the dead processor
4521 * so that the vm statistics are consistent.
4523 * This is only okay since the processor is dead and cannot
4524 * race with what we are doing.
4526 refresh_cpu_vm_stats(cpu
);
4531 void __init
page_alloc_init(void)
4533 hotcpu_notifier(page_alloc_cpu_notify
, 0);
4537 * calculate_totalreserve_pages - called when sysctl_lower_zone_reserve_ratio
4538 * or min_free_kbytes changes.
4540 static void calculate_totalreserve_pages(void)
4542 struct pglist_data
*pgdat
;
4543 unsigned long reserve_pages
= 0;
4544 enum zone_type i
, j
;
4546 for_each_online_pgdat(pgdat
) {
4547 for (i
= 0; i
< MAX_NR_ZONES
; i
++) {
4548 struct zone
*zone
= pgdat
->node_zones
+ i
;
4549 unsigned long max
= 0;
4551 /* Find valid and maximum lowmem_reserve in the zone */
4552 for (j
= i
; j
< MAX_NR_ZONES
; j
++) {
4553 if (zone
->lowmem_reserve
[j
] > max
)
4554 max
= zone
->lowmem_reserve
[j
];
4557 /* we treat the high watermark as reserved pages. */
4558 max
+= high_wmark_pages(zone
);
4560 if (max
> zone
->present_pages
)
4561 max
= zone
->present_pages
;
4562 reserve_pages
+= max
;
4565 totalreserve_pages
= reserve_pages
;
4569 * setup_per_zone_lowmem_reserve - called whenever
4570 * sysctl_lower_zone_reserve_ratio changes. Ensures that each zone
4571 * has a correct pages reserved value, so an adequate number of
4572 * pages are left in the zone after a successful __alloc_pages().
4574 static void setup_per_zone_lowmem_reserve(void)
4576 struct pglist_data
*pgdat
;
4577 enum zone_type j
, idx
;
4579 for_each_online_pgdat(pgdat
) {
4580 for (j
= 0; j
< MAX_NR_ZONES
; j
++) {
4581 struct zone
*zone
= pgdat
->node_zones
+ j
;
4582 unsigned long present_pages
= zone
->present_pages
;
4584 zone
->lowmem_reserve
[j
] = 0;
4588 struct zone
*lower_zone
;
4592 if (sysctl_lowmem_reserve_ratio
[idx
] < 1)
4593 sysctl_lowmem_reserve_ratio
[idx
] = 1;
4595 lower_zone
= pgdat
->node_zones
+ idx
;
4596 lower_zone
->lowmem_reserve
[j
] = present_pages
/
4597 sysctl_lowmem_reserve_ratio
[idx
];
4598 present_pages
+= lower_zone
->present_pages
;
4603 /* update totalreserve_pages */
4604 calculate_totalreserve_pages();
4608 * setup_per_zone_wmarks - called when min_free_kbytes changes
4609 * or when memory is hot-{added|removed}
4611 * Ensures that the watermark[min,low,high] values for each zone are set
4612 * correctly with respect to min_free_kbytes.
4614 void setup_per_zone_wmarks(void)
4616 unsigned long pages_min
= min_free_kbytes
>> (PAGE_SHIFT
- 10);
4617 unsigned long lowmem_pages
= 0;
4619 unsigned long flags
;
4621 /* Calculate total number of !ZONE_HIGHMEM pages */
4622 for_each_zone(zone
) {
4623 if (!is_highmem(zone
))
4624 lowmem_pages
+= zone
->present_pages
;
4627 for_each_zone(zone
) {
4630 spin_lock_irqsave(&zone
->lock
, flags
);
4631 tmp
= (u64
)pages_min
* zone
->present_pages
;
4632 do_div(tmp
, lowmem_pages
);
4633 if (is_highmem(zone
)) {
4635 * __GFP_HIGH and PF_MEMALLOC allocations usually don't
4636 * need highmem pages, so cap pages_min to a small
4639 * The WMARK_HIGH-WMARK_LOW and (WMARK_LOW-WMARK_MIN)
4640 * deltas controls asynch page reclaim, and so should
4641 * not be capped for highmem.
4645 min_pages
= zone
->present_pages
/ 1024;
4646 if (min_pages
< SWAP_CLUSTER_MAX
)
4647 min_pages
= SWAP_CLUSTER_MAX
;
4648 if (min_pages
> 128)
4650 zone
->watermark
[WMARK_MIN
] = min_pages
;
4653 * If it's a lowmem zone, reserve a number of pages
4654 * proportionate to the zone's size.
4656 zone
->watermark
[WMARK_MIN
] = tmp
;
4659 zone
->watermark
[WMARK_LOW
] = min_wmark_pages(zone
) + (tmp
>> 2);
4660 zone
->watermark
[WMARK_HIGH
] = min_wmark_pages(zone
) + (tmp
>> 1);
4661 setup_zone_migrate_reserve(zone
);
4662 spin_unlock_irqrestore(&zone
->lock
, flags
);
4665 /* update totalreserve_pages */
4666 calculate_totalreserve_pages();
4670 * The inactive anon list should be small enough that the VM never has to
4671 * do too much work, but large enough that each inactive page has a chance
4672 * to be referenced again before it is swapped out.
4674 * The inactive_anon ratio is the target ratio of ACTIVE_ANON to
4675 * INACTIVE_ANON pages on this zone's LRU, maintained by the
4676 * pageout code. A zone->inactive_ratio of 3 means 3:1 or 25% of
4677 * the anonymous pages are kept on the inactive list.
4680 * memory ratio inactive anon
4681 * -------------------------------------
4690 void calculate_zone_inactive_ratio(struct zone
*zone
)
4692 unsigned int gb
, ratio
;
4694 /* Zone size in gigabytes */
4695 gb
= zone
->present_pages
>> (30 - PAGE_SHIFT
);
4697 ratio
= int_sqrt(10 * gb
);
4701 zone
->inactive_ratio
= ratio
;
4704 static void __init
setup_per_zone_inactive_ratio(void)
4709 calculate_zone_inactive_ratio(zone
);
4713 * Initialise min_free_kbytes.
4715 * For small machines we want it small (128k min). For large machines
4716 * we want it large (64MB max). But it is not linear, because network
4717 * bandwidth does not increase linearly with machine size. We use
4719 * min_free_kbytes = 4 * sqrt(lowmem_kbytes), for better accuracy:
4720 * min_free_kbytes = sqrt(lowmem_kbytes * 16)
4736 static int __init
init_per_zone_wmark_min(void)
4738 unsigned long lowmem_kbytes
;
4740 lowmem_kbytes
= nr_free_buffer_pages() * (PAGE_SIZE
>> 10);
4742 min_free_kbytes
= int_sqrt(lowmem_kbytes
* 16);
4743 if (min_free_kbytes
< 128)
4744 min_free_kbytes
= 128;
4745 if (min_free_kbytes
> 65536)
4746 min_free_kbytes
= 65536;
4747 setup_per_zone_wmarks();
4748 setup_per_zone_lowmem_reserve();
4749 setup_per_zone_inactive_ratio();
4752 module_init(init_per_zone_wmark_min
)
4755 * min_free_kbytes_sysctl_handler - just a wrapper around proc_dointvec() so
4756 * that we can call two helper functions whenever min_free_kbytes
4759 int min_free_kbytes_sysctl_handler(ctl_table
*table
, int write
,
4760 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
4762 proc_dointvec(table
, write
, buffer
, length
, ppos
);
4764 setup_per_zone_wmarks();
4769 int sysctl_min_unmapped_ratio_sysctl_handler(ctl_table
*table
, int write
,
4770 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
4775 rc
= proc_dointvec_minmax(table
, write
, buffer
, length
, ppos
);
4780 zone
->min_unmapped_pages
= (zone
->present_pages
*
4781 sysctl_min_unmapped_ratio
) / 100;
4785 int sysctl_min_slab_ratio_sysctl_handler(ctl_table
*table
, int write
,
4786 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
4791 rc
= proc_dointvec_minmax(table
, write
, buffer
, length
, ppos
);
4796 zone
->min_slab_pages
= (zone
->present_pages
*
4797 sysctl_min_slab_ratio
) / 100;
4803 * lowmem_reserve_ratio_sysctl_handler - just a wrapper around
4804 * proc_dointvec() so that we can call setup_per_zone_lowmem_reserve()
4805 * whenever sysctl_lowmem_reserve_ratio changes.
4807 * The reserve ratio obviously has absolutely no relation with the
4808 * minimum watermarks. The lowmem reserve ratio can only make sense
4809 * if in function of the boot time zone sizes.
4811 int lowmem_reserve_ratio_sysctl_handler(ctl_table
*table
, int write
,
4812 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
4814 proc_dointvec_minmax(table
, write
, buffer
, length
, ppos
);
4815 setup_per_zone_lowmem_reserve();
4820 * percpu_pagelist_fraction - changes the pcp->high for each zone on each
4821 * cpu. It is the fraction of total pages in each zone that a hot per cpu pagelist
4822 * can have before it gets flushed back to buddy allocator.
4825 int percpu_pagelist_fraction_sysctl_handler(ctl_table
*table
, int write
,
4826 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
4832 ret
= proc_dointvec_minmax(table
, write
, buffer
, length
, ppos
);
4833 if (!write
|| (ret
== -EINVAL
))
4835 for_each_populated_zone(zone
) {
4836 for_each_possible_cpu(cpu
) {
4838 high
= zone
->present_pages
/ percpu_pagelist_fraction
;
4839 setup_pagelist_highmark(
4840 per_cpu_ptr(zone
->pageset
, cpu
), high
);
4846 int hashdist
= HASHDIST_DEFAULT
;
4849 static int __init
set_hashdist(char *str
)
4853 hashdist
= simple_strtoul(str
, &str
, 0);
4856 __setup("hashdist=", set_hashdist
);
4860 * allocate a large system hash table from bootmem
4861 * - it is assumed that the hash table must contain an exact power-of-2
4862 * quantity of entries
4863 * - limit is the number of hash buckets, not the total allocation size
4865 void *__init
alloc_large_system_hash(const char *tablename
,
4866 unsigned long bucketsize
,
4867 unsigned long numentries
,
4870 unsigned int *_hash_shift
,
4871 unsigned int *_hash_mask
,
4872 unsigned long limit
)
4874 unsigned long long max
= limit
;
4875 unsigned long log2qty
, size
;
4878 /* allow the kernel cmdline to have a say */
4880 /* round applicable memory size up to nearest megabyte */
4881 numentries
= nr_kernel_pages
;
4882 numentries
+= (1UL << (20 - PAGE_SHIFT
)) - 1;
4883 numentries
>>= 20 - PAGE_SHIFT
;
4884 numentries
<<= 20 - PAGE_SHIFT
;
4886 /* limit to 1 bucket per 2^scale bytes of low memory */
4887 if (scale
> PAGE_SHIFT
)
4888 numentries
>>= (scale
- PAGE_SHIFT
);
4890 numentries
<<= (PAGE_SHIFT
- scale
);
4892 /* Make sure we've got at least a 0-order allocation.. */
4893 if (unlikely(flags
& HASH_SMALL
)) {
4894 /* Makes no sense without HASH_EARLY */
4895 WARN_ON(!(flags
& HASH_EARLY
));
4896 if (!(numentries
>> *_hash_shift
)) {
4897 numentries
= 1UL << *_hash_shift
;
4898 BUG_ON(!numentries
);
4900 } else if (unlikely((numentries
* bucketsize
) < PAGE_SIZE
))
4901 numentries
= PAGE_SIZE
/ bucketsize
;
4903 numentries
= roundup_pow_of_two(numentries
);
4905 /* limit allocation size to 1/16 total memory by default */
4907 max
= ((unsigned long long)nr_all_pages
<< PAGE_SHIFT
) >> 4;
4908 do_div(max
, bucketsize
);
4911 if (numentries
> max
)
4914 log2qty
= ilog2(numentries
);
4917 size
= bucketsize
<< log2qty
;
4918 if (flags
& HASH_EARLY
)
4919 table
= alloc_bootmem_nopanic(size
);
4921 table
= __vmalloc(size
, GFP_ATOMIC
, PAGE_KERNEL
);
4924 * If bucketsize is not a power-of-two, we may free
4925 * some pages at the end of hash table which
4926 * alloc_pages_exact() automatically does
4928 if (get_order(size
) < MAX_ORDER
) {
4929 table
= alloc_pages_exact(size
, GFP_ATOMIC
);
4930 kmemleak_alloc(table
, size
, 1, GFP_ATOMIC
);
4933 } while (!table
&& size
> PAGE_SIZE
&& --log2qty
);
4936 panic("Failed to allocate %s hash table\n", tablename
);
4938 printk(KERN_INFO
"%s hash table entries: %d (order: %d, %lu bytes)\n",
4941 ilog2(size
) - PAGE_SHIFT
,
4945 *_hash_shift
= log2qty
;
4947 *_hash_mask
= (1 << log2qty
) - 1;
4952 /* Return a pointer to the bitmap storing bits affecting a block of pages */
4953 static inline unsigned long *get_pageblock_bitmap(struct zone
*zone
,
4956 #ifdef CONFIG_SPARSEMEM
4957 return __pfn_to_section(pfn
)->pageblock_flags
;
4959 return zone
->pageblock_flags
;
4960 #endif /* CONFIG_SPARSEMEM */
4963 static inline int pfn_to_bitidx(struct zone
*zone
, unsigned long pfn
)
4965 #ifdef CONFIG_SPARSEMEM
4966 pfn
&= (PAGES_PER_SECTION
-1);
4967 return (pfn
>> pageblock_order
) * NR_PAGEBLOCK_BITS
;
4969 pfn
= pfn
- zone
->zone_start_pfn
;
4970 return (pfn
>> pageblock_order
) * NR_PAGEBLOCK_BITS
;
4971 #endif /* CONFIG_SPARSEMEM */
4975 * get_pageblock_flags_group - Return the requested group of flags for the pageblock_nr_pages block of pages
4976 * @page: The page within the block of interest
4977 * @start_bitidx: The first bit of interest to retrieve
4978 * @end_bitidx: The last bit of interest
4979 * returns pageblock_bits flags
4981 unsigned long get_pageblock_flags_group(struct page
*page
,
4982 int start_bitidx
, int end_bitidx
)
4985 unsigned long *bitmap
;
4986 unsigned long pfn
, bitidx
;
4987 unsigned long flags
= 0;
4988 unsigned long value
= 1;
4990 zone
= page_zone(page
);
4991 pfn
= page_to_pfn(page
);
4992 bitmap
= get_pageblock_bitmap(zone
, pfn
);
4993 bitidx
= pfn_to_bitidx(zone
, pfn
);
4995 for (; start_bitidx
<= end_bitidx
; start_bitidx
++, value
<<= 1)
4996 if (test_bit(bitidx
+ start_bitidx
, bitmap
))
5003 * set_pageblock_flags_group - Set the requested group of flags for a pageblock_nr_pages block of pages
5004 * @page: The page within the block of interest
5005 * @start_bitidx: The first bit of interest
5006 * @end_bitidx: The last bit of interest
5007 * @flags: The flags to set
5009 void set_pageblock_flags_group(struct page
*page
, unsigned long flags
,
5010 int start_bitidx
, int end_bitidx
)
5013 unsigned long *bitmap
;
5014 unsigned long pfn
, bitidx
;
5015 unsigned long value
= 1;
5017 zone
= page_zone(page
);
5018 pfn
= page_to_pfn(page
);
5019 bitmap
= get_pageblock_bitmap(zone
, pfn
);
5020 bitidx
= pfn_to_bitidx(zone
, pfn
);
5021 VM_BUG_ON(pfn
< zone
->zone_start_pfn
);
5022 VM_BUG_ON(pfn
>= zone
->zone_start_pfn
+ zone
->spanned_pages
);
5024 for (; start_bitidx
<= end_bitidx
; start_bitidx
++, value
<<= 1)
5026 __set_bit(bitidx
+ start_bitidx
, bitmap
);
5028 __clear_bit(bitidx
+ start_bitidx
, bitmap
);
5032 * This is designed as sub function...plz see page_isolation.c also.
5033 * set/clear page block's type to be ISOLATE.
5034 * page allocater never alloc memory from ISOLATE block.
5037 int set_migratetype_isolate(struct page
*page
)
5040 struct page
*curr_page
;
5041 unsigned long flags
, pfn
, iter
;
5042 unsigned long immobile
= 0;
5043 struct memory_isolate_notify arg
;
5048 zone
= page_zone(page
);
5049 zone_idx
= zone_idx(zone
);
5051 spin_lock_irqsave(&zone
->lock
, flags
);
5052 if (get_pageblock_migratetype(page
) == MIGRATE_MOVABLE
||
5053 zone_idx
== ZONE_MOVABLE
) {
5058 pfn
= page_to_pfn(page
);
5059 arg
.start_pfn
= pfn
;
5060 arg
.nr_pages
= pageblock_nr_pages
;
5061 arg
.pages_found
= 0;
5064 * It may be possible to isolate a pageblock even if the
5065 * migratetype is not MIGRATE_MOVABLE. The memory isolation
5066 * notifier chain is used by balloon drivers to return the
5067 * number of pages in a range that are held by the balloon
5068 * driver to shrink memory. If all the pages are accounted for
5069 * by balloons, are free, or on the LRU, isolation can continue.
5070 * Later, for example, when memory hotplug notifier runs, these
5071 * pages reported as "can be isolated" should be isolated(freed)
5072 * by the balloon driver through the memory notifier chain.
5074 notifier_ret
= memory_isolate_notify(MEM_ISOLATE_COUNT
, &arg
);
5075 notifier_ret
= notifier_to_errno(notifier_ret
);
5076 if (notifier_ret
|| !arg
.pages_found
)
5079 for (iter
= pfn
; iter
< (pfn
+ pageblock_nr_pages
); iter
++) {
5080 if (!pfn_valid_within(pfn
))
5083 curr_page
= pfn_to_page(iter
);
5084 if (!page_count(curr_page
) || PageLRU(curr_page
))
5090 if (arg
.pages_found
== immobile
)
5095 set_pageblock_migratetype(page
, MIGRATE_ISOLATE
);
5096 move_freepages_block(zone
, page
, MIGRATE_ISOLATE
);
5099 spin_unlock_irqrestore(&zone
->lock
, flags
);
5105 void unset_migratetype_isolate(struct page
*page
)
5108 unsigned long flags
;
5109 zone
= page_zone(page
);
5110 spin_lock_irqsave(&zone
->lock
, flags
);
5111 if (get_pageblock_migratetype(page
) != MIGRATE_ISOLATE
)
5113 set_pageblock_migratetype(page
, MIGRATE_MOVABLE
);
5114 move_freepages_block(zone
, page
, MIGRATE_MOVABLE
);
5116 spin_unlock_irqrestore(&zone
->lock
, flags
);
5119 #ifdef CONFIG_MEMORY_HOTREMOVE
5121 * All pages in the range must be isolated before calling this.
5124 __offline_isolated_pages(unsigned long start_pfn
, unsigned long end_pfn
)
5130 unsigned long flags
;
5131 /* find the first valid pfn */
5132 for (pfn
= start_pfn
; pfn
< end_pfn
; pfn
++)
5137 zone
= page_zone(pfn_to_page(pfn
));
5138 spin_lock_irqsave(&zone
->lock
, flags
);
5140 while (pfn
< end_pfn
) {
5141 if (!pfn_valid(pfn
)) {
5145 page
= pfn_to_page(pfn
);
5146 BUG_ON(page_count(page
));
5147 BUG_ON(!PageBuddy(page
));
5148 order
= page_order(page
);
5149 #ifdef CONFIG_DEBUG_VM
5150 printk(KERN_INFO
"remove from free list %lx %d %lx\n",
5151 pfn
, 1 << order
, end_pfn
);
5153 list_del(&page
->lru
);
5154 rmv_page_order(page
);
5155 zone
->free_area
[order
].nr_free
--;
5156 __mod_zone_page_state(zone
, NR_FREE_PAGES
,
5158 for (i
= 0; i
< (1 << order
); i
++)
5159 SetPageReserved((page
+i
));
5160 pfn
+= (1 << order
);
5162 spin_unlock_irqrestore(&zone
->lock
, flags
);
5166 #ifdef CONFIG_MEMORY_FAILURE
5167 bool is_free_buddy_page(struct page
*page
)
5169 struct zone
*zone
= page_zone(page
);
5170 unsigned long pfn
= page_to_pfn(page
);
5171 unsigned long flags
;
5174 spin_lock_irqsave(&zone
->lock
, flags
);
5175 for (order
= 0; order
< MAX_ORDER
; order
++) {
5176 struct page
*page_head
= page
- (pfn
& ((1 << order
) - 1));
5178 if (PageBuddy(page_head
) && page_order(page_head
) >= order
)
5181 spin_unlock_irqrestore(&zone
->lock
, flags
);
5183 return order
< MAX_ORDER
;