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/memblock.h>
25 #include <linux/compiler.h>
26 #include <linux/kernel.h>
27 #include <linux/kmemcheck.h>
28 #include <linux/module.h>
29 #include <linux/suspend.h>
30 #include <linux/pagevec.h>
31 #include <linux/blkdev.h>
32 #include <linux/slab.h>
33 #include <linux/ratelimit.h>
34 #include <linux/oom.h>
35 #include <linux/notifier.h>
36 #include <linux/topology.h>
37 #include <linux/sysctl.h>
38 #include <linux/cpu.h>
39 #include <linux/cpuset.h>
40 #include <linux/memory_hotplug.h>
41 #include <linux/nodemask.h>
42 #include <linux/vmalloc.h>
43 #include <linux/vmstat.h>
44 #include <linux/mempolicy.h>
45 #include <linux/stop_machine.h>
46 #include <linux/sort.h>
47 #include <linux/pfn.h>
48 #include <linux/backing-dev.h>
49 #include <linux/fault-inject.h>
50 #include <linux/page-isolation.h>
51 #include <linux/page_cgroup.h>
52 #include <linux/debugobjects.h>
53 #include <linux/kmemleak.h>
54 #include <linux/compaction.h>
55 #include <trace/events/kmem.h>
56 #include <linux/ftrace_event.h>
57 #include <linux/memcontrol.h>
58 #include <linux/prefetch.h>
59 #include <linux/migrate.h>
60 #include <linux/page-debug-flags.h>
62 #include <asm/tlbflush.h>
63 #include <asm/div64.h>
66 #ifdef CONFIG_USE_PERCPU_NUMA_NODE_ID
67 DEFINE_PER_CPU(int, numa_node
);
68 EXPORT_PER_CPU_SYMBOL(numa_node
);
71 #ifdef CONFIG_HAVE_MEMORYLESS_NODES
73 * N.B., Do NOT reference the '_numa_mem_' per cpu variable directly.
74 * It will not be defined when CONFIG_HAVE_MEMORYLESS_NODES is not defined.
75 * Use the accessor functions set_numa_mem(), numa_mem_id() and cpu_to_mem()
76 * defined in <linux/topology.h>.
78 DEFINE_PER_CPU(int, _numa_mem_
); /* Kernel "local memory" node */
79 EXPORT_PER_CPU_SYMBOL(_numa_mem_
);
83 * Array of node states.
85 nodemask_t node_states
[NR_NODE_STATES
] __read_mostly
= {
86 [N_POSSIBLE
] = NODE_MASK_ALL
,
87 [N_ONLINE
] = { { [0] = 1UL } },
89 [N_NORMAL_MEMORY
] = { { [0] = 1UL } },
91 [N_HIGH_MEMORY
] = { { [0] = 1UL } },
93 [N_CPU
] = { { [0] = 1UL } },
96 EXPORT_SYMBOL(node_states
);
98 unsigned long totalram_pages __read_mostly
;
99 unsigned long totalreserve_pages __read_mostly
;
101 * When calculating the number of globally allowed dirty pages, there
102 * is a certain number of per-zone reserves that should not be
103 * considered dirtyable memory. This is the sum of those reserves
104 * over all existing zones that contribute dirtyable memory.
106 unsigned long dirty_balance_reserve __read_mostly
;
108 int percpu_pagelist_fraction
;
109 gfp_t gfp_allowed_mask __read_mostly
= GFP_BOOT_MASK
;
111 #ifdef CONFIG_PM_SLEEP
113 * The following functions are used by the suspend/hibernate code to temporarily
114 * change gfp_allowed_mask in order to avoid using I/O during memory allocations
115 * while devices are suspended. To avoid races with the suspend/hibernate code,
116 * they should always be called with pm_mutex held (gfp_allowed_mask also should
117 * only be modified with pm_mutex held, unless the suspend/hibernate code is
118 * guaranteed not to run in parallel with that modification).
121 static gfp_t saved_gfp_mask
;
123 void pm_restore_gfp_mask(void)
125 WARN_ON(!mutex_is_locked(&pm_mutex
));
126 if (saved_gfp_mask
) {
127 gfp_allowed_mask
= saved_gfp_mask
;
132 void pm_restrict_gfp_mask(void)
134 WARN_ON(!mutex_is_locked(&pm_mutex
));
135 WARN_ON(saved_gfp_mask
);
136 saved_gfp_mask
= gfp_allowed_mask
;
137 gfp_allowed_mask
&= ~GFP_IOFS
;
140 bool pm_suspended_storage(void)
142 if ((gfp_allowed_mask
& GFP_IOFS
) == GFP_IOFS
)
146 #endif /* CONFIG_PM_SLEEP */
148 #ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
149 int pageblock_order __read_mostly
;
152 static void __free_pages_ok(struct page
*page
, unsigned int order
);
155 * results with 256, 32 in the lowmem_reserve sysctl:
156 * 1G machine -> (16M dma, 800M-16M normal, 1G-800M high)
157 * 1G machine -> (16M dma, 784M normal, 224M high)
158 * NORMAL allocation will leave 784M/256 of ram reserved in the ZONE_DMA
159 * HIGHMEM allocation will leave 224M/32 of ram reserved in ZONE_NORMAL
160 * HIGHMEM allocation will (224M+784M)/256 of ram reserved in ZONE_DMA
162 * TBD: should special case ZONE_DMA32 machines here - in those we normally
163 * don't need any ZONE_NORMAL reservation
165 int sysctl_lowmem_reserve_ratio
[MAX_NR_ZONES
-1] = {
166 #ifdef CONFIG_ZONE_DMA
169 #ifdef CONFIG_ZONE_DMA32
172 #ifdef CONFIG_HIGHMEM
178 EXPORT_SYMBOL(totalram_pages
);
180 static char * const zone_names
[MAX_NR_ZONES
] = {
181 #ifdef CONFIG_ZONE_DMA
184 #ifdef CONFIG_ZONE_DMA32
188 #ifdef CONFIG_HIGHMEM
194 int min_free_kbytes
= 1024;
196 static unsigned long __meminitdata nr_kernel_pages
;
197 static unsigned long __meminitdata nr_all_pages
;
198 static unsigned long __meminitdata dma_reserve
;
200 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
201 static unsigned long __meminitdata arch_zone_lowest_possible_pfn
[MAX_NR_ZONES
];
202 static unsigned long __meminitdata arch_zone_highest_possible_pfn
[MAX_NR_ZONES
];
203 static unsigned long __initdata required_kernelcore
;
204 static unsigned long __initdata required_movablecore
;
205 static unsigned long __meminitdata zone_movable_pfn
[MAX_NUMNODES
];
207 /* movable_zone is the "real" zone pages in ZONE_MOVABLE are taken from */
209 EXPORT_SYMBOL(movable_zone
);
210 #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
213 int nr_node_ids __read_mostly
= MAX_NUMNODES
;
214 int nr_online_nodes __read_mostly
= 1;
215 EXPORT_SYMBOL(nr_node_ids
);
216 EXPORT_SYMBOL(nr_online_nodes
);
219 int page_group_by_mobility_disabled __read_mostly
;
223 * Don't use set_pageblock_migratetype(page, MIGRATE_ISOLATE) directly.
224 * Instead, use {un}set_pageblock_isolate.
226 void set_pageblock_migratetype(struct page
*page
, int migratetype
)
229 if (unlikely(page_group_by_mobility_disabled
))
230 migratetype
= MIGRATE_UNMOVABLE
;
232 set_pageblock_flags_group(page
, (unsigned long)migratetype
,
233 PB_migrate
, PB_migrate_end
);
236 bool oom_killer_disabled __read_mostly
;
238 #ifdef CONFIG_DEBUG_VM
239 static int page_outside_zone_boundaries(struct zone
*zone
, struct page
*page
)
243 unsigned long pfn
= page_to_pfn(page
);
246 seq
= zone_span_seqbegin(zone
);
247 if (pfn
>= zone
->zone_start_pfn
+ zone
->spanned_pages
)
249 else if (pfn
< zone
->zone_start_pfn
)
251 } while (zone_span_seqretry(zone
, seq
));
256 static int page_is_consistent(struct zone
*zone
, struct page
*page
)
258 if (!pfn_valid_within(page_to_pfn(page
)))
260 if (zone
!= page_zone(page
))
266 * Temporary debugging check for pages not lying within a given zone.
268 static int bad_range(struct zone
*zone
, struct page
*page
)
270 if (page_outside_zone_boundaries(zone
, page
))
272 if (!page_is_consistent(zone
, page
))
278 static inline int bad_range(struct zone
*zone
, struct page
*page
)
284 static void bad_page(struct page
*page
)
286 static unsigned long resume
;
287 static unsigned long nr_shown
;
288 static unsigned long nr_unshown
;
290 /* Don't complain about poisoned pages */
291 if (PageHWPoison(page
)) {
292 reset_page_mapcount(page
); /* remove PageBuddy */
297 * Allow a burst of 60 reports, then keep quiet for that minute;
298 * or allow a steady drip of one report per second.
300 if (nr_shown
== 60) {
301 if (time_before(jiffies
, resume
)) {
307 "BUG: Bad page state: %lu messages suppressed\n",
314 resume
= jiffies
+ 60 * HZ
;
316 printk(KERN_ALERT
"BUG: Bad page state in process %s pfn:%05lx\n",
317 current
->comm
, page_to_pfn(page
));
323 /* Leave bad fields for debug, except PageBuddy could make trouble */
324 reset_page_mapcount(page
); /* remove PageBuddy */
325 add_taint(TAINT_BAD_PAGE
);
329 * Higher-order pages are called "compound pages". They are structured thusly:
331 * The first PAGE_SIZE page is called the "head page".
333 * The remaining PAGE_SIZE pages are called "tail pages".
335 * All pages have PG_compound set. All tail pages have their ->first_page
336 * pointing at the head page.
338 * The first tail page's ->lru.next holds the address of the compound page's
339 * put_page() function. Its ->lru.prev holds the order of allocation.
340 * This usage means that zero-order pages may not be compound.
343 static void free_compound_page(struct page
*page
)
345 __free_pages_ok(page
, compound_order(page
));
348 void prep_compound_page(struct page
*page
, unsigned long order
)
351 int nr_pages
= 1 << order
;
353 set_compound_page_dtor(page
, free_compound_page
);
354 set_compound_order(page
, order
);
356 for (i
= 1; i
< nr_pages
; i
++) {
357 struct page
*p
= page
+ i
;
359 set_page_count(p
, 0);
360 p
->first_page
= page
;
364 /* update __split_huge_page_refcount if you change this function */
365 static int destroy_compound_page(struct page
*page
, unsigned long order
)
368 int nr_pages
= 1 << order
;
371 if (unlikely(compound_order(page
) != order
) ||
372 unlikely(!PageHead(page
))) {
377 __ClearPageHead(page
);
379 for (i
= 1; i
< nr_pages
; i
++) {
380 struct page
*p
= page
+ i
;
382 if (unlikely(!PageTail(p
) || (p
->first_page
!= page
))) {
392 static inline void prep_zero_page(struct page
*page
, int order
, gfp_t gfp_flags
)
397 * clear_highpage() will use KM_USER0, so it's a bug to use __GFP_ZERO
398 * and __GFP_HIGHMEM from hard or soft interrupt context.
400 VM_BUG_ON((gfp_flags
& __GFP_HIGHMEM
) && in_interrupt());
401 for (i
= 0; i
< (1 << order
); i
++)
402 clear_highpage(page
+ i
);
405 #ifdef CONFIG_DEBUG_PAGEALLOC
406 unsigned int _debug_guardpage_minorder
;
408 static int __init
debug_guardpage_minorder_setup(char *buf
)
412 if (kstrtoul(buf
, 10, &res
) < 0 || res
> MAX_ORDER
/ 2) {
413 printk(KERN_ERR
"Bad debug_guardpage_minorder value\n");
416 _debug_guardpage_minorder
= res
;
417 printk(KERN_INFO
"Setting debug_guardpage_minorder to %lu\n", res
);
420 __setup("debug_guardpage_minorder=", debug_guardpage_minorder_setup
);
422 static inline void set_page_guard_flag(struct page
*page
)
424 __set_bit(PAGE_DEBUG_FLAG_GUARD
, &page
->debug_flags
);
427 static inline void clear_page_guard_flag(struct page
*page
)
429 __clear_bit(PAGE_DEBUG_FLAG_GUARD
, &page
->debug_flags
);
432 static inline void set_page_guard_flag(struct page
*page
) { }
433 static inline void clear_page_guard_flag(struct page
*page
) { }
436 static inline void set_page_order(struct page
*page
, int order
)
438 set_page_private(page
, order
);
439 __SetPageBuddy(page
);
442 static inline void rmv_page_order(struct page
*page
)
444 __ClearPageBuddy(page
);
445 set_page_private(page
, 0);
449 * Locate the struct page for both the matching buddy in our
450 * pair (buddy1) and the combined O(n+1) page they form (page).
452 * 1) Any buddy B1 will have an order O twin B2 which satisfies
453 * the following equation:
455 * For example, if the starting buddy (buddy2) is #8 its order
457 * B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10
459 * 2) Any buddy B will have an order O+1 parent P which
460 * satisfies the following equation:
463 * Assumption: *_mem_map is contiguous at least up to MAX_ORDER
465 static inline unsigned long
466 __find_buddy_index(unsigned long page_idx
, unsigned int order
)
468 return page_idx
^ (1 << order
);
472 * This function checks whether a page is free && is the buddy
473 * we can do coalesce a page and its buddy if
474 * (a) the buddy is not in a hole &&
475 * (b) the buddy is in the buddy system &&
476 * (c) a page and its buddy have the same order &&
477 * (d) a page and its buddy are in the same zone.
479 * For recording whether a page is in the buddy system, we set ->_mapcount -2.
480 * Setting, clearing, and testing _mapcount -2 is serialized by zone->lock.
482 * For recording page's order, we use page_private(page).
484 static inline int page_is_buddy(struct page
*page
, struct page
*buddy
,
487 if (!pfn_valid_within(page_to_pfn(buddy
)))
490 if (page_zone_id(page
) != page_zone_id(buddy
))
493 if (page_is_guard(buddy
) && page_order(buddy
) == order
) {
494 VM_BUG_ON(page_count(buddy
) != 0);
498 if (PageBuddy(buddy
) && page_order(buddy
) == order
) {
499 VM_BUG_ON(page_count(buddy
) != 0);
506 * Freeing function for a buddy system allocator.
508 * The concept of a buddy system is to maintain direct-mapped table
509 * (containing bit values) for memory blocks of various "orders".
510 * The bottom level table contains the map for the smallest allocatable
511 * units of memory (here, pages), and each level above it describes
512 * pairs of units from the levels below, hence, "buddies".
513 * At a high level, all that happens here is marking the table entry
514 * at the bottom level available, and propagating the changes upward
515 * as necessary, plus some accounting needed to play nicely with other
516 * parts of the VM system.
517 * At each level, we keep a list of pages, which are heads of continuous
518 * free pages of length of (1 << order) and marked with _mapcount -2. Page's
519 * order is recorded in page_private(page) field.
520 * So when we are allocating or freeing one, we can derive the state of the
521 * other. That is, if we allocate a small block, and both were
522 * free, the remainder of the region must be split into blocks.
523 * If a block is freed, and its buddy is also free, then this
524 * triggers coalescing into a block of larger size.
529 static inline void __free_one_page(struct page
*page
,
530 struct zone
*zone
, unsigned int order
,
533 unsigned long page_idx
;
534 unsigned long combined_idx
;
535 unsigned long uninitialized_var(buddy_idx
);
538 if (unlikely(PageCompound(page
)))
539 if (unlikely(destroy_compound_page(page
, order
)))
542 VM_BUG_ON(migratetype
== -1);
544 page_idx
= page_to_pfn(page
) & ((1 << MAX_ORDER
) - 1);
546 VM_BUG_ON(page_idx
& ((1 << order
) - 1));
547 VM_BUG_ON(bad_range(zone
, page
));
549 while (order
< MAX_ORDER
-1) {
550 buddy_idx
= __find_buddy_index(page_idx
, order
);
551 buddy
= page
+ (buddy_idx
- page_idx
);
552 if (!page_is_buddy(page
, buddy
, order
))
555 * Our buddy is free or it is CONFIG_DEBUG_PAGEALLOC guard page,
556 * merge with it and move up one order.
558 if (page_is_guard(buddy
)) {
559 clear_page_guard_flag(buddy
);
560 set_page_private(page
, 0);
561 __mod_zone_page_state(zone
, NR_FREE_PAGES
, 1 << order
);
563 list_del(&buddy
->lru
);
564 zone
->free_area
[order
].nr_free
--;
565 rmv_page_order(buddy
);
567 combined_idx
= buddy_idx
& page_idx
;
568 page
= page
+ (combined_idx
- page_idx
);
569 page_idx
= combined_idx
;
572 set_page_order(page
, order
);
575 * If this is not the largest possible page, check if the buddy
576 * of the next-highest order is free. If it is, it's possible
577 * that pages are being freed that will coalesce soon. In case,
578 * that is happening, add the free page to the tail of the list
579 * so it's less likely to be used soon and more likely to be merged
580 * as a higher order page
582 if ((order
< MAX_ORDER
-2) && pfn_valid_within(page_to_pfn(buddy
))) {
583 struct page
*higher_page
, *higher_buddy
;
584 combined_idx
= buddy_idx
& page_idx
;
585 higher_page
= page
+ (combined_idx
- page_idx
);
586 buddy_idx
= __find_buddy_index(combined_idx
, order
+ 1);
587 higher_buddy
= page
+ (buddy_idx
- combined_idx
);
588 if (page_is_buddy(higher_page
, higher_buddy
, order
+ 1)) {
589 list_add_tail(&page
->lru
,
590 &zone
->free_area
[order
].free_list
[migratetype
]);
595 list_add(&page
->lru
, &zone
->free_area
[order
].free_list
[migratetype
]);
597 zone
->free_area
[order
].nr_free
++;
601 * free_page_mlock() -- clean up attempts to free and mlocked() page.
602 * Page should not be on lru, so no need to fix that up.
603 * free_pages_check() will verify...
605 static inline void free_page_mlock(struct page
*page
)
607 __dec_zone_page_state(page
, NR_MLOCK
);
608 __count_vm_event(UNEVICTABLE_MLOCKFREED
);
611 static inline int free_pages_check(struct page
*page
)
613 if (unlikely(page_mapcount(page
) |
614 (page
->mapping
!= NULL
) |
615 (atomic_read(&page
->_count
) != 0) |
616 (page
->flags
& PAGE_FLAGS_CHECK_AT_FREE
) |
617 (mem_cgroup_bad_page_check(page
)))) {
621 if (page
->flags
& PAGE_FLAGS_CHECK_AT_PREP
)
622 page
->flags
&= ~PAGE_FLAGS_CHECK_AT_PREP
;
627 * Frees a number of pages from the PCP lists
628 * Assumes all pages on list are in same zone, and of same order.
629 * count is the number of pages to free.
631 * If the zone was previously in an "all pages pinned" state then look to
632 * see if this freeing clears that state.
634 * And clear the zone's pages_scanned counter, to hold off the "all pages are
635 * pinned" detection logic.
637 static void free_pcppages_bulk(struct zone
*zone
, int count
,
638 struct per_cpu_pages
*pcp
)
644 spin_lock(&zone
->lock
);
645 zone
->all_unreclaimable
= 0;
646 zone
->pages_scanned
= 0;
650 struct list_head
*list
;
653 * Remove pages from lists in a round-robin fashion. A
654 * batch_free count is maintained that is incremented when an
655 * empty list is encountered. This is so more pages are freed
656 * off fuller lists instead of spinning excessively around empty
661 if (++migratetype
== MIGRATE_PCPTYPES
)
663 list
= &pcp
->lists
[migratetype
];
664 } while (list_empty(list
));
666 /* This is the only non-empty list. Free them all. */
667 if (batch_free
== MIGRATE_PCPTYPES
)
668 batch_free
= to_free
;
671 page
= list_entry(list
->prev
, struct page
, lru
);
672 /* must delete as __free_one_page list manipulates */
673 list_del(&page
->lru
);
674 /* MIGRATE_MOVABLE list may include MIGRATE_RESERVEs */
675 __free_one_page(page
, zone
, 0, page_private(page
));
676 trace_mm_page_pcpu_drain(page
, 0, page_private(page
));
677 } while (--to_free
&& --batch_free
&& !list_empty(list
));
679 __mod_zone_page_state(zone
, NR_FREE_PAGES
, count
);
680 spin_unlock(&zone
->lock
);
683 static void free_one_page(struct zone
*zone
, struct page
*page
, int order
,
686 spin_lock(&zone
->lock
);
687 zone
->all_unreclaimable
= 0;
688 zone
->pages_scanned
= 0;
690 __free_one_page(page
, zone
, order
, migratetype
);
691 __mod_zone_page_state(zone
, NR_FREE_PAGES
, 1 << order
);
692 spin_unlock(&zone
->lock
);
695 static bool free_pages_prepare(struct page
*page
, unsigned int order
)
700 trace_mm_page_free(page
, order
);
701 kmemcheck_free_shadow(page
, order
);
704 page
->mapping
= NULL
;
705 for (i
= 0; i
< (1 << order
); i
++)
706 bad
+= free_pages_check(page
+ i
);
710 if (!PageHighMem(page
)) {
711 debug_check_no_locks_freed(page_address(page
),PAGE_SIZE
<<order
);
712 debug_check_no_obj_freed(page_address(page
),
715 arch_free_page(page
, order
);
716 kernel_map_pages(page
, 1 << order
, 0);
721 static void __free_pages_ok(struct page
*page
, unsigned int order
)
724 int wasMlocked
= __TestClearPageMlocked(page
);
726 if (!free_pages_prepare(page
, order
))
729 local_irq_save(flags
);
730 if (unlikely(wasMlocked
))
731 free_page_mlock(page
);
732 __count_vm_events(PGFREE
, 1 << order
);
733 free_one_page(page_zone(page
), page
, order
,
734 get_pageblock_migratetype(page
));
735 local_irq_restore(flags
);
738 void __meminit
__free_pages_bootmem(struct page
*page
, unsigned int order
)
740 unsigned int nr_pages
= 1 << order
;
744 for (loop
= 0; loop
< nr_pages
; loop
++) {
745 struct page
*p
= &page
[loop
];
747 if (loop
+ 1 < nr_pages
)
749 __ClearPageReserved(p
);
750 set_page_count(p
, 0);
753 set_page_refcounted(page
);
754 __free_pages(page
, order
);
758 /* Free whole pageblock and set it's migration type to MIGRATE_CMA. */
759 void __init
init_cma_reserved_pageblock(struct page
*page
)
761 unsigned i
= pageblock_nr_pages
;
762 struct page
*p
= page
;
765 __ClearPageReserved(p
);
766 set_page_count(p
, 0);
769 set_page_refcounted(page
);
770 set_pageblock_migratetype(page
, MIGRATE_CMA
);
771 __free_pages(page
, pageblock_order
);
772 totalram_pages
+= pageblock_nr_pages
;
777 * The order of subdivision here is critical for the IO subsystem.
778 * Please do not alter this order without good reasons and regression
779 * testing. Specifically, as large blocks of memory are subdivided,
780 * the order in which smaller blocks are delivered depends on the order
781 * they're subdivided in this function. This is the primary factor
782 * influencing the order in which pages are delivered to the IO
783 * subsystem according to empirical testing, and this is also justified
784 * by considering the behavior of a buddy system containing a single
785 * large block of memory acted on by a series of small allocations.
786 * This behavior is a critical factor in sglist merging's success.
790 static inline void expand(struct zone
*zone
, struct page
*page
,
791 int low
, int high
, struct free_area
*area
,
794 unsigned long size
= 1 << high
;
800 VM_BUG_ON(bad_range(zone
, &page
[size
]));
802 #ifdef CONFIG_DEBUG_PAGEALLOC
803 if (high
< debug_guardpage_minorder()) {
805 * Mark as guard pages (or page), that will allow to
806 * merge back to allocator when buddy will be freed.
807 * Corresponding page table entries will not be touched,
808 * pages will stay not present in virtual address space
810 INIT_LIST_HEAD(&page
[size
].lru
);
811 set_page_guard_flag(&page
[size
]);
812 set_page_private(&page
[size
], high
);
813 /* Guard pages are not available for any usage */
814 __mod_zone_page_state(zone
, NR_FREE_PAGES
, -(1 << high
));
818 list_add(&page
[size
].lru
, &area
->free_list
[migratetype
]);
820 set_page_order(&page
[size
], high
);
825 * This page is about to be returned from the page allocator
827 static inline int check_new_page(struct page
*page
)
829 if (unlikely(page_mapcount(page
) |
830 (page
->mapping
!= NULL
) |
831 (atomic_read(&page
->_count
) != 0) |
832 (page
->flags
& PAGE_FLAGS_CHECK_AT_PREP
) |
833 (mem_cgroup_bad_page_check(page
)))) {
840 static int prep_new_page(struct page
*page
, int order
, gfp_t gfp_flags
)
844 for (i
= 0; i
< (1 << order
); i
++) {
845 struct page
*p
= page
+ i
;
846 if (unlikely(check_new_page(p
)))
850 set_page_private(page
, 0);
851 set_page_refcounted(page
);
853 arch_alloc_page(page
, order
);
854 kernel_map_pages(page
, 1 << order
, 1);
856 if (gfp_flags
& __GFP_ZERO
)
857 prep_zero_page(page
, order
, gfp_flags
);
859 if (order
&& (gfp_flags
& __GFP_COMP
))
860 prep_compound_page(page
, order
);
866 * Go through the free lists for the given migratetype and remove
867 * the smallest available page from the freelists
870 struct page
*__rmqueue_smallest(struct zone
*zone
, unsigned int order
,
873 unsigned int current_order
;
874 struct free_area
* area
;
877 /* Find a page of the appropriate size in the preferred list */
878 for (current_order
= order
; current_order
< MAX_ORDER
; ++current_order
) {
879 area
= &(zone
->free_area
[current_order
]);
880 if (list_empty(&area
->free_list
[migratetype
]))
883 page
= list_entry(area
->free_list
[migratetype
].next
,
885 list_del(&page
->lru
);
886 rmv_page_order(page
);
888 expand(zone
, page
, order
, current_order
, area
, migratetype
);
897 * This array describes the order lists are fallen back to when
898 * the free lists for the desirable migrate type are depleted
900 static int fallbacks
[MIGRATE_TYPES
][4] = {
901 [MIGRATE_UNMOVABLE
] = { MIGRATE_RECLAIMABLE
, MIGRATE_MOVABLE
, MIGRATE_RESERVE
},
902 [MIGRATE_RECLAIMABLE
] = { MIGRATE_UNMOVABLE
, MIGRATE_MOVABLE
, MIGRATE_RESERVE
},
904 [MIGRATE_MOVABLE
] = { MIGRATE_CMA
, MIGRATE_RECLAIMABLE
, MIGRATE_UNMOVABLE
, MIGRATE_RESERVE
},
905 [MIGRATE_CMA
] = { MIGRATE_RESERVE
}, /* Never used */
907 [MIGRATE_MOVABLE
] = { MIGRATE_RECLAIMABLE
, MIGRATE_UNMOVABLE
, MIGRATE_RESERVE
},
909 [MIGRATE_RESERVE
] = { MIGRATE_RESERVE
}, /* Never used */
910 [MIGRATE_ISOLATE
] = { MIGRATE_RESERVE
}, /* Never used */
914 * Move the free pages in a range to the free lists of the requested type.
915 * Note that start_page and end_pages are not aligned on a pageblock
916 * boundary. If alignment is required, use move_freepages_block()
918 static int move_freepages(struct zone
*zone
,
919 struct page
*start_page
, struct page
*end_page
,
926 #ifndef CONFIG_HOLES_IN_ZONE
928 * page_zone is not safe to call in this context when
929 * CONFIG_HOLES_IN_ZONE is set. This bug check is probably redundant
930 * anyway as we check zone boundaries in move_freepages_block().
931 * Remove at a later date when no bug reports exist related to
932 * grouping pages by mobility
934 BUG_ON(page_zone(start_page
) != page_zone(end_page
));
937 for (page
= start_page
; page
<= end_page
;) {
938 /* Make sure we are not inadvertently changing nodes */
939 VM_BUG_ON(page_to_nid(page
) != zone_to_nid(zone
));
941 if (!pfn_valid_within(page_to_pfn(page
))) {
946 if (!PageBuddy(page
)) {
951 order
= page_order(page
);
952 list_move(&page
->lru
,
953 &zone
->free_area
[order
].free_list
[migratetype
]);
955 pages_moved
+= 1 << order
;
961 int move_freepages_block(struct zone
*zone
, struct page
*page
,
964 unsigned long start_pfn
, end_pfn
;
965 struct page
*start_page
, *end_page
;
967 start_pfn
= page_to_pfn(page
);
968 start_pfn
= start_pfn
& ~(pageblock_nr_pages
-1);
969 start_page
= pfn_to_page(start_pfn
);
970 end_page
= start_page
+ pageblock_nr_pages
- 1;
971 end_pfn
= start_pfn
+ pageblock_nr_pages
- 1;
973 /* Do not cross zone boundaries */
974 if (start_pfn
< zone
->zone_start_pfn
)
976 if (end_pfn
>= zone
->zone_start_pfn
+ zone
->spanned_pages
)
979 return move_freepages(zone
, start_page
, end_page
, migratetype
);
982 static void change_pageblock_range(struct page
*pageblock_page
,
983 int start_order
, int migratetype
)
985 int nr_pageblocks
= 1 << (start_order
- pageblock_order
);
987 while (nr_pageblocks
--) {
988 set_pageblock_migratetype(pageblock_page
, migratetype
);
989 pageblock_page
+= pageblock_nr_pages
;
993 /* Remove an element from the buddy allocator from the fallback list */
994 static inline struct page
*
995 __rmqueue_fallback(struct zone
*zone
, int order
, int start_migratetype
)
997 struct free_area
* area
;
1002 /* Find the largest possible block of pages in the other list */
1003 for (current_order
= MAX_ORDER
-1; current_order
>= order
;
1006 migratetype
= fallbacks
[start_migratetype
][i
];
1008 /* MIGRATE_RESERVE handled later if necessary */
1009 if (migratetype
== MIGRATE_RESERVE
)
1012 area
= &(zone
->free_area
[current_order
]);
1013 if (list_empty(&area
->free_list
[migratetype
]))
1016 page
= list_entry(area
->free_list
[migratetype
].next
,
1021 * If breaking a large block of pages, move all free
1022 * pages to the preferred allocation list. If falling
1023 * back for a reclaimable kernel allocation, be more
1024 * aggressive about taking ownership of free pages
1026 * On the other hand, never change migration
1027 * type of MIGRATE_CMA pageblocks nor move CMA
1028 * pages on different free lists. We don't
1029 * want unmovable pages to be allocated from
1030 * MIGRATE_CMA areas.
1032 if (!is_migrate_cma(migratetype
) &&
1033 (unlikely(current_order
>= pageblock_order
/ 2) ||
1034 start_migratetype
== MIGRATE_RECLAIMABLE
||
1035 page_group_by_mobility_disabled
)) {
1037 pages
= move_freepages_block(zone
, page
,
1040 /* Claim the whole block if over half of it is free */
1041 if (pages
>= (1 << (pageblock_order
-1)) ||
1042 page_group_by_mobility_disabled
)
1043 set_pageblock_migratetype(page
,
1046 migratetype
= start_migratetype
;
1049 /* Remove the page from the freelists */
1050 list_del(&page
->lru
);
1051 rmv_page_order(page
);
1053 /* Take ownership for orders >= pageblock_order */
1054 if (current_order
>= pageblock_order
&&
1055 !is_migrate_cma(migratetype
))
1056 change_pageblock_range(page
, current_order
,
1059 expand(zone
, page
, order
, current_order
, area
,
1060 is_migrate_cma(migratetype
)
1061 ? migratetype
: start_migratetype
);
1063 trace_mm_page_alloc_extfrag(page
, order
, current_order
,
1064 start_migratetype
, migratetype
);
1074 * Do the hard work of removing an element from the buddy allocator.
1075 * Call me with the zone->lock already held.
1077 static struct page
*__rmqueue(struct zone
*zone
, unsigned int order
,
1083 page
= __rmqueue_smallest(zone
, order
, migratetype
);
1085 if (unlikely(!page
) && migratetype
!= MIGRATE_RESERVE
) {
1086 page
= __rmqueue_fallback(zone
, order
, migratetype
);
1089 * Use MIGRATE_RESERVE rather than fail an allocation. goto
1090 * is used because __rmqueue_smallest is an inline function
1091 * and we want just one call site
1094 migratetype
= MIGRATE_RESERVE
;
1099 trace_mm_page_alloc_zone_locked(page
, order
, migratetype
);
1104 * Obtain a specified number of elements from the buddy allocator, all under
1105 * a single hold of the lock, for efficiency. Add them to the supplied list.
1106 * Returns the number of new pages which were placed at *list.
1108 static int rmqueue_bulk(struct zone
*zone
, unsigned int order
,
1109 unsigned long count
, struct list_head
*list
,
1110 int migratetype
, int cold
)
1112 int mt
= migratetype
, i
;
1114 spin_lock(&zone
->lock
);
1115 for (i
= 0; i
< count
; ++i
) {
1116 struct page
*page
= __rmqueue(zone
, order
, migratetype
);
1117 if (unlikely(page
== NULL
))
1121 * Split buddy pages returned by expand() are received here
1122 * in physical page order. The page is added to the callers and
1123 * list and the list head then moves forward. From the callers
1124 * perspective, the linked list is ordered by page number in
1125 * some conditions. This is useful for IO devices that can
1126 * merge IO requests if the physical pages are ordered
1129 if (likely(cold
== 0))
1130 list_add(&page
->lru
, list
);
1132 list_add_tail(&page
->lru
, list
);
1133 if (IS_ENABLED(CONFIG_CMA
)) {
1134 mt
= get_pageblock_migratetype(page
);
1135 if (!is_migrate_cma(mt
) && mt
!= MIGRATE_ISOLATE
)
1138 set_page_private(page
, mt
);
1141 __mod_zone_page_state(zone
, NR_FREE_PAGES
, -(i
<< order
));
1142 spin_unlock(&zone
->lock
);
1148 * Called from the vmstat counter updater to drain pagesets of this
1149 * currently executing processor on remote nodes after they have
1152 * Note that this function must be called with the thread pinned to
1153 * a single processor.
1155 void drain_zone_pages(struct zone
*zone
, struct per_cpu_pages
*pcp
)
1157 unsigned long flags
;
1160 local_irq_save(flags
);
1161 if (pcp
->count
>= pcp
->batch
)
1162 to_drain
= pcp
->batch
;
1164 to_drain
= pcp
->count
;
1166 free_pcppages_bulk(zone
, to_drain
, pcp
);
1167 pcp
->count
-= to_drain
;
1169 local_irq_restore(flags
);
1174 * Drain pages of the indicated processor.
1176 * The processor must either be the current processor and the
1177 * thread pinned to the current processor or a processor that
1180 static void drain_pages(unsigned int cpu
)
1182 unsigned long flags
;
1185 for_each_populated_zone(zone
) {
1186 struct per_cpu_pageset
*pset
;
1187 struct per_cpu_pages
*pcp
;
1189 local_irq_save(flags
);
1190 pset
= per_cpu_ptr(zone
->pageset
, cpu
);
1194 free_pcppages_bulk(zone
, pcp
->count
, pcp
);
1197 local_irq_restore(flags
);
1202 * Spill all of this CPU's per-cpu pages back into the buddy allocator.
1204 void drain_local_pages(void *arg
)
1206 drain_pages(smp_processor_id());
1210 * Spill all the per-cpu pages from all CPUs back into the buddy allocator.
1212 * Note that this code is protected against sending an IPI to an offline
1213 * CPU but does not guarantee sending an IPI to newly hotplugged CPUs:
1214 * on_each_cpu_mask() blocks hotplug and won't talk to offlined CPUs but
1215 * nothing keeps CPUs from showing up after we populated the cpumask and
1216 * before the call to on_each_cpu_mask().
1218 void drain_all_pages(void)
1221 struct per_cpu_pageset
*pcp
;
1225 * Allocate in the BSS so we wont require allocation in
1226 * direct reclaim path for CONFIG_CPUMASK_OFFSTACK=y
1228 static cpumask_t cpus_with_pcps
;
1231 * We don't care about racing with CPU hotplug event
1232 * as offline notification will cause the notified
1233 * cpu to drain that CPU pcps and on_each_cpu_mask
1234 * disables preemption as part of its processing
1236 for_each_online_cpu(cpu
) {
1237 bool has_pcps
= false;
1238 for_each_populated_zone(zone
) {
1239 pcp
= per_cpu_ptr(zone
->pageset
, cpu
);
1240 if (pcp
->pcp
.count
) {
1246 cpumask_set_cpu(cpu
, &cpus_with_pcps
);
1248 cpumask_clear_cpu(cpu
, &cpus_with_pcps
);
1250 on_each_cpu_mask(&cpus_with_pcps
, drain_local_pages
, NULL
, 1);
1253 #ifdef CONFIG_HIBERNATION
1255 void mark_free_pages(struct zone
*zone
)
1257 unsigned long pfn
, max_zone_pfn
;
1258 unsigned long flags
;
1260 struct list_head
*curr
;
1262 if (!zone
->spanned_pages
)
1265 spin_lock_irqsave(&zone
->lock
, flags
);
1267 max_zone_pfn
= zone
->zone_start_pfn
+ zone
->spanned_pages
;
1268 for (pfn
= zone
->zone_start_pfn
; pfn
< max_zone_pfn
; pfn
++)
1269 if (pfn_valid(pfn
)) {
1270 struct page
*page
= pfn_to_page(pfn
);
1272 if (!swsusp_page_is_forbidden(page
))
1273 swsusp_unset_page_free(page
);
1276 for_each_migratetype_order(order
, t
) {
1277 list_for_each(curr
, &zone
->free_area
[order
].free_list
[t
]) {
1280 pfn
= page_to_pfn(list_entry(curr
, struct page
, lru
));
1281 for (i
= 0; i
< (1UL << order
); i
++)
1282 swsusp_set_page_free(pfn_to_page(pfn
+ i
));
1285 spin_unlock_irqrestore(&zone
->lock
, flags
);
1287 #endif /* CONFIG_PM */
1290 * Free a 0-order page
1291 * cold == 1 ? free a cold page : free a hot page
1293 void free_hot_cold_page(struct page
*page
, int cold
)
1295 struct zone
*zone
= page_zone(page
);
1296 struct per_cpu_pages
*pcp
;
1297 unsigned long flags
;
1299 int wasMlocked
= __TestClearPageMlocked(page
);
1301 if (!free_pages_prepare(page
, 0))
1304 migratetype
= get_pageblock_migratetype(page
);
1305 set_page_private(page
, migratetype
);
1306 local_irq_save(flags
);
1307 if (unlikely(wasMlocked
))
1308 free_page_mlock(page
);
1309 __count_vm_event(PGFREE
);
1312 * We only track unmovable, reclaimable and movable on pcp lists.
1313 * Free ISOLATE pages back to the allocator because they are being
1314 * offlined but treat RESERVE as movable pages so we can get those
1315 * areas back if necessary. Otherwise, we may have to free
1316 * excessively into the page allocator
1318 if (migratetype
>= MIGRATE_PCPTYPES
) {
1319 if (unlikely(migratetype
== MIGRATE_ISOLATE
)) {
1320 free_one_page(zone
, page
, 0, migratetype
);
1323 migratetype
= MIGRATE_MOVABLE
;
1326 pcp
= &this_cpu_ptr(zone
->pageset
)->pcp
;
1328 list_add_tail(&page
->lru
, &pcp
->lists
[migratetype
]);
1330 list_add(&page
->lru
, &pcp
->lists
[migratetype
]);
1332 if (pcp
->count
>= pcp
->high
) {
1333 free_pcppages_bulk(zone
, pcp
->batch
, pcp
);
1334 pcp
->count
-= pcp
->batch
;
1338 local_irq_restore(flags
);
1342 * Free a list of 0-order pages
1344 void free_hot_cold_page_list(struct list_head
*list
, int cold
)
1346 struct page
*page
, *next
;
1348 list_for_each_entry_safe(page
, next
, list
, lru
) {
1349 trace_mm_page_free_batched(page
, cold
);
1350 free_hot_cold_page(page
, cold
);
1355 * split_page takes a non-compound higher-order page, and splits it into
1356 * n (1<<order) sub-pages: page[0..n]
1357 * Each sub-page must be freed individually.
1359 * Note: this is probably too low level an operation for use in drivers.
1360 * Please consult with lkml before using this in your driver.
1362 void split_page(struct page
*page
, unsigned int order
)
1366 VM_BUG_ON(PageCompound(page
));
1367 VM_BUG_ON(!page_count(page
));
1369 #ifdef CONFIG_KMEMCHECK
1371 * Split shadow pages too, because free(page[0]) would
1372 * otherwise free the whole shadow.
1374 if (kmemcheck_page_is_tracked(page
))
1375 split_page(virt_to_page(page
[0].shadow
), order
);
1378 for (i
= 1; i
< (1 << order
); i
++)
1379 set_page_refcounted(page
+ i
);
1383 * Similar to split_page except the page is already free. As this is only
1384 * being used for migration, the migratetype of the block also changes.
1385 * As this is called with interrupts disabled, the caller is responsible
1386 * for calling arch_alloc_page() and kernel_map_page() after interrupts
1389 * Note: this is probably too low level an operation for use in drivers.
1390 * Please consult with lkml before using this in your driver.
1392 int split_free_page(struct page
*page
)
1395 unsigned long watermark
;
1398 BUG_ON(!PageBuddy(page
));
1400 zone
= page_zone(page
);
1401 order
= page_order(page
);
1403 /* Obey watermarks as if the page was being allocated */
1404 watermark
= low_wmark_pages(zone
) + (1 << order
);
1405 if (!zone_watermark_ok(zone
, 0, watermark
, 0, 0))
1408 /* Remove page from free list */
1409 list_del(&page
->lru
);
1410 zone
->free_area
[order
].nr_free
--;
1411 rmv_page_order(page
);
1412 __mod_zone_page_state(zone
, NR_FREE_PAGES
, -(1UL << order
));
1414 /* Split into individual pages */
1415 set_page_refcounted(page
);
1416 split_page(page
, order
);
1418 if (order
>= pageblock_order
- 1) {
1419 struct page
*endpage
= page
+ (1 << order
) - 1;
1420 for (; page
< endpage
; page
+= pageblock_nr_pages
) {
1421 int mt
= get_pageblock_migratetype(page
);
1422 if (mt
!= MIGRATE_ISOLATE
&& !is_migrate_cma(mt
))
1423 set_pageblock_migratetype(page
,
1432 * Really, prep_compound_page() should be called from __rmqueue_bulk(). But
1433 * we cheat by calling it from here, in the order > 0 path. Saves a branch
1437 struct page
*buffered_rmqueue(struct zone
*preferred_zone
,
1438 struct zone
*zone
, int order
, gfp_t gfp_flags
,
1441 unsigned long flags
;
1443 int cold
= !!(gfp_flags
& __GFP_COLD
);
1446 if (likely(order
== 0)) {
1447 struct per_cpu_pages
*pcp
;
1448 struct list_head
*list
;
1450 local_irq_save(flags
);
1451 pcp
= &this_cpu_ptr(zone
->pageset
)->pcp
;
1452 list
= &pcp
->lists
[migratetype
];
1453 if (list_empty(list
)) {
1454 pcp
->count
+= rmqueue_bulk(zone
, 0,
1457 if (unlikely(list_empty(list
)))
1462 page
= list_entry(list
->prev
, struct page
, lru
);
1464 page
= list_entry(list
->next
, struct page
, lru
);
1466 list_del(&page
->lru
);
1469 if (unlikely(gfp_flags
& __GFP_NOFAIL
)) {
1471 * __GFP_NOFAIL is not to be used in new code.
1473 * All __GFP_NOFAIL callers should be fixed so that they
1474 * properly detect and handle allocation failures.
1476 * We most definitely don't want callers attempting to
1477 * allocate greater than order-1 page units with
1480 WARN_ON_ONCE(order
> 1);
1482 spin_lock_irqsave(&zone
->lock
, flags
);
1483 page
= __rmqueue(zone
, order
, migratetype
);
1484 spin_unlock(&zone
->lock
);
1487 __mod_zone_page_state(zone
, NR_FREE_PAGES
, -(1 << order
));
1490 __count_zone_vm_events(PGALLOC
, zone
, 1 << order
);
1491 zone_statistics(preferred_zone
, zone
, gfp_flags
);
1492 local_irq_restore(flags
);
1494 VM_BUG_ON(bad_range(zone
, page
));
1495 if (prep_new_page(page
, order
, gfp_flags
))
1500 local_irq_restore(flags
);
1504 /* The ALLOC_WMARK bits are used as an index to zone->watermark */
1505 #define ALLOC_WMARK_MIN WMARK_MIN
1506 #define ALLOC_WMARK_LOW WMARK_LOW
1507 #define ALLOC_WMARK_HIGH WMARK_HIGH
1508 #define ALLOC_NO_WATERMARKS 0x04 /* don't check watermarks at all */
1510 /* Mask to get the watermark bits */
1511 #define ALLOC_WMARK_MASK (ALLOC_NO_WATERMARKS-1)
1513 #define ALLOC_HARDER 0x10 /* try to alloc harder */
1514 #define ALLOC_HIGH 0x20 /* __GFP_HIGH set */
1515 #define ALLOC_CPUSET 0x40 /* check for correct cpuset */
1517 #ifdef CONFIG_FAIL_PAGE_ALLOC
1520 struct fault_attr attr
;
1522 u32 ignore_gfp_highmem
;
1523 u32 ignore_gfp_wait
;
1525 } fail_page_alloc
= {
1526 .attr
= FAULT_ATTR_INITIALIZER
,
1527 .ignore_gfp_wait
= 1,
1528 .ignore_gfp_highmem
= 1,
1532 static int __init
setup_fail_page_alloc(char *str
)
1534 return setup_fault_attr(&fail_page_alloc
.attr
, str
);
1536 __setup("fail_page_alloc=", setup_fail_page_alloc
);
1538 static bool should_fail_alloc_page(gfp_t gfp_mask
, unsigned int order
)
1540 if (order
< fail_page_alloc
.min_order
)
1542 if (gfp_mask
& __GFP_NOFAIL
)
1544 if (fail_page_alloc
.ignore_gfp_highmem
&& (gfp_mask
& __GFP_HIGHMEM
))
1546 if (fail_page_alloc
.ignore_gfp_wait
&& (gfp_mask
& __GFP_WAIT
))
1549 return should_fail(&fail_page_alloc
.attr
, 1 << order
);
1552 #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
1554 static int __init
fail_page_alloc_debugfs(void)
1556 umode_t mode
= S_IFREG
| S_IRUSR
| S_IWUSR
;
1559 dir
= fault_create_debugfs_attr("fail_page_alloc", NULL
,
1560 &fail_page_alloc
.attr
);
1562 return PTR_ERR(dir
);
1564 if (!debugfs_create_bool("ignore-gfp-wait", mode
, dir
,
1565 &fail_page_alloc
.ignore_gfp_wait
))
1567 if (!debugfs_create_bool("ignore-gfp-highmem", mode
, dir
,
1568 &fail_page_alloc
.ignore_gfp_highmem
))
1570 if (!debugfs_create_u32("min-order", mode
, dir
,
1571 &fail_page_alloc
.min_order
))
1576 debugfs_remove_recursive(dir
);
1581 late_initcall(fail_page_alloc_debugfs
);
1583 #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
1585 #else /* CONFIG_FAIL_PAGE_ALLOC */
1587 static inline bool should_fail_alloc_page(gfp_t gfp_mask
, unsigned int order
)
1592 #endif /* CONFIG_FAIL_PAGE_ALLOC */
1595 * Return true if free pages are above 'mark'. This takes into account the order
1596 * of the allocation.
1598 static bool __zone_watermark_ok(struct zone
*z
, int order
, unsigned long mark
,
1599 int classzone_idx
, int alloc_flags
, long free_pages
)
1601 /* free_pages my go negative - that's OK */
1603 long lowmem_reserve
= z
->lowmem_reserve
[classzone_idx
];
1606 free_pages
-= (1 << order
) - 1;
1607 if (alloc_flags
& ALLOC_HIGH
)
1609 if (alloc_flags
& ALLOC_HARDER
)
1612 if (free_pages
<= min
+ lowmem_reserve
)
1614 for (o
= 0; o
< order
; o
++) {
1615 /* At the next order, this order's pages become unavailable */
1616 free_pages
-= z
->free_area
[o
].nr_free
<< o
;
1618 /* Require fewer higher order pages to be free */
1621 if (free_pages
<= min
)
1627 #ifdef CONFIG_MEMORY_ISOLATION
1628 static inline unsigned long nr_zone_isolate_freepages(struct zone
*zone
)
1630 if (unlikely(zone
->nr_pageblock_isolate
))
1631 return zone
->nr_pageblock_isolate
* pageblock_nr_pages
;
1635 static inline unsigned long nr_zone_isolate_freepages(struct zone
*zone
)
1641 bool zone_watermark_ok(struct zone
*z
, int order
, unsigned long mark
,
1642 int classzone_idx
, int alloc_flags
)
1644 return __zone_watermark_ok(z
, order
, mark
, classzone_idx
, alloc_flags
,
1645 zone_page_state(z
, NR_FREE_PAGES
));
1648 bool zone_watermark_ok_safe(struct zone
*z
, int order
, unsigned long mark
,
1649 int classzone_idx
, int alloc_flags
)
1651 long free_pages
= zone_page_state(z
, NR_FREE_PAGES
);
1653 if (z
->percpu_drift_mark
&& free_pages
< z
->percpu_drift_mark
)
1654 free_pages
= zone_page_state_snapshot(z
, NR_FREE_PAGES
);
1657 * If the zone has MIGRATE_ISOLATE type free pages, we should consider
1658 * it. nr_zone_isolate_freepages is never accurate so kswapd might not
1659 * sleep although it could do so. But this is more desirable for memory
1660 * hotplug than sleeping which can cause a livelock in the direct
1663 free_pages
-= nr_zone_isolate_freepages(z
);
1664 return __zone_watermark_ok(z
, order
, mark
, classzone_idx
, alloc_flags
,
1670 * zlc_setup - Setup for "zonelist cache". Uses cached zone data to
1671 * skip over zones that are not allowed by the cpuset, or that have
1672 * been recently (in last second) found to be nearly full. See further
1673 * comments in mmzone.h. Reduces cache footprint of zonelist scans
1674 * that have to skip over a lot of full or unallowed zones.
1676 * If the zonelist cache is present in the passed in zonelist, then
1677 * returns a pointer to the allowed node mask (either the current
1678 * tasks mems_allowed, or node_states[N_HIGH_MEMORY].)
1680 * If the zonelist cache is not available for this zonelist, does
1681 * nothing and returns NULL.
1683 * If the fullzones BITMAP in the zonelist cache is stale (more than
1684 * a second since last zap'd) then we zap it out (clear its bits.)
1686 * We hold off even calling zlc_setup, until after we've checked the
1687 * first zone in the zonelist, on the theory that most allocations will
1688 * be satisfied from that first zone, so best to examine that zone as
1689 * quickly as we can.
1691 static nodemask_t
*zlc_setup(struct zonelist
*zonelist
, int alloc_flags
)
1693 struct zonelist_cache
*zlc
; /* cached zonelist speedup info */
1694 nodemask_t
*allowednodes
; /* zonelist_cache approximation */
1696 zlc
= zonelist
->zlcache_ptr
;
1700 if (time_after(jiffies
, zlc
->last_full_zap
+ HZ
)) {
1701 bitmap_zero(zlc
->fullzones
, MAX_ZONES_PER_ZONELIST
);
1702 zlc
->last_full_zap
= jiffies
;
1705 allowednodes
= !in_interrupt() && (alloc_flags
& ALLOC_CPUSET
) ?
1706 &cpuset_current_mems_allowed
:
1707 &node_states
[N_HIGH_MEMORY
];
1708 return allowednodes
;
1712 * Given 'z' scanning a zonelist, run a couple of quick checks to see
1713 * if it is worth looking at further for free memory:
1714 * 1) Check that the zone isn't thought to be full (doesn't have its
1715 * bit set in the zonelist_cache fullzones BITMAP).
1716 * 2) Check that the zones node (obtained from the zonelist_cache
1717 * z_to_n[] mapping) is allowed in the passed in allowednodes mask.
1718 * Return true (non-zero) if zone is worth looking at further, or
1719 * else return false (zero) if it is not.
1721 * This check -ignores- the distinction between various watermarks,
1722 * such as GFP_HIGH, GFP_ATOMIC, PF_MEMALLOC, ... If a zone is
1723 * found to be full for any variation of these watermarks, it will
1724 * be considered full for up to one second by all requests, unless
1725 * we are so low on memory on all allowed nodes that we are forced
1726 * into the second scan of the zonelist.
1728 * In the second scan we ignore this zonelist cache and exactly
1729 * apply the watermarks to all zones, even it is slower to do so.
1730 * We are low on memory in the second scan, and should leave no stone
1731 * unturned looking for a free page.
1733 static int zlc_zone_worth_trying(struct zonelist
*zonelist
, struct zoneref
*z
,
1734 nodemask_t
*allowednodes
)
1736 struct zonelist_cache
*zlc
; /* cached zonelist speedup info */
1737 int i
; /* index of *z in zonelist zones */
1738 int n
; /* node that zone *z is on */
1740 zlc
= zonelist
->zlcache_ptr
;
1744 i
= z
- zonelist
->_zonerefs
;
1747 /* This zone is worth trying if it is allowed but not full */
1748 return node_isset(n
, *allowednodes
) && !test_bit(i
, zlc
->fullzones
);
1752 * Given 'z' scanning a zonelist, set the corresponding bit in
1753 * zlc->fullzones, so that subsequent attempts to allocate a page
1754 * from that zone don't waste time re-examining it.
1756 static void zlc_mark_zone_full(struct zonelist
*zonelist
, struct zoneref
*z
)
1758 struct zonelist_cache
*zlc
; /* cached zonelist speedup info */
1759 int i
; /* index of *z in zonelist zones */
1761 zlc
= zonelist
->zlcache_ptr
;
1765 i
= z
- zonelist
->_zonerefs
;
1767 set_bit(i
, zlc
->fullzones
);
1771 * clear all zones full, called after direct reclaim makes progress so that
1772 * a zone that was recently full is not skipped over for up to a second
1774 static void zlc_clear_zones_full(struct zonelist
*zonelist
)
1776 struct zonelist_cache
*zlc
; /* cached zonelist speedup info */
1778 zlc
= zonelist
->zlcache_ptr
;
1782 bitmap_zero(zlc
->fullzones
, MAX_ZONES_PER_ZONELIST
);
1785 #else /* CONFIG_NUMA */
1787 static nodemask_t
*zlc_setup(struct zonelist
*zonelist
, int alloc_flags
)
1792 static int zlc_zone_worth_trying(struct zonelist
*zonelist
, struct zoneref
*z
,
1793 nodemask_t
*allowednodes
)
1798 static void zlc_mark_zone_full(struct zonelist
*zonelist
, struct zoneref
*z
)
1802 static void zlc_clear_zones_full(struct zonelist
*zonelist
)
1805 #endif /* CONFIG_NUMA */
1808 * get_page_from_freelist goes through the zonelist trying to allocate
1811 static struct page
*
1812 get_page_from_freelist(gfp_t gfp_mask
, nodemask_t
*nodemask
, unsigned int order
,
1813 struct zonelist
*zonelist
, int high_zoneidx
, int alloc_flags
,
1814 struct zone
*preferred_zone
, int migratetype
)
1817 struct page
*page
= NULL
;
1820 nodemask_t
*allowednodes
= NULL
;/* zonelist_cache approximation */
1821 int zlc_active
= 0; /* set if using zonelist_cache */
1822 int did_zlc_setup
= 0; /* just call zlc_setup() one time */
1824 classzone_idx
= zone_idx(preferred_zone
);
1827 * Scan zonelist, looking for a zone with enough free.
1828 * See also cpuset_zone_allowed() comment in kernel/cpuset.c.
1830 for_each_zone_zonelist_nodemask(zone
, z
, zonelist
,
1831 high_zoneidx
, nodemask
) {
1832 if (NUMA_BUILD
&& zlc_active
&&
1833 !zlc_zone_worth_trying(zonelist
, z
, allowednodes
))
1835 if ((alloc_flags
& ALLOC_CPUSET
) &&
1836 !cpuset_zone_allowed_softwall(zone
, gfp_mask
))
1839 * When allocating a page cache page for writing, we
1840 * want to get it from a zone that is within its dirty
1841 * limit, such that no single zone holds more than its
1842 * proportional share of globally allowed dirty pages.
1843 * The dirty limits take into account the zone's
1844 * lowmem reserves and high watermark so that kswapd
1845 * should be able to balance it without having to
1846 * write pages from its LRU list.
1848 * This may look like it could increase pressure on
1849 * lower zones by failing allocations in higher zones
1850 * before they are full. But the pages that do spill
1851 * over are limited as the lower zones are protected
1852 * by this very same mechanism. It should not become
1853 * a practical burden to them.
1855 * XXX: For now, allow allocations to potentially
1856 * exceed the per-zone dirty limit in the slowpath
1857 * (ALLOC_WMARK_LOW unset) before going into reclaim,
1858 * which is important when on a NUMA setup the allowed
1859 * zones are together not big enough to reach the
1860 * global limit. The proper fix for these situations
1861 * will require awareness of zones in the
1862 * dirty-throttling and the flusher threads.
1864 if ((alloc_flags
& ALLOC_WMARK_LOW
) &&
1865 (gfp_mask
& __GFP_WRITE
) && !zone_dirty_ok(zone
))
1866 goto this_zone_full
;
1868 BUILD_BUG_ON(ALLOC_NO_WATERMARKS
< NR_WMARK
);
1869 if (!(alloc_flags
& ALLOC_NO_WATERMARKS
)) {
1873 mark
= zone
->watermark
[alloc_flags
& ALLOC_WMARK_MASK
];
1874 if (zone_watermark_ok(zone
, order
, mark
,
1875 classzone_idx
, alloc_flags
))
1878 if (NUMA_BUILD
&& !did_zlc_setup
&& nr_online_nodes
> 1) {
1880 * we do zlc_setup if there are multiple nodes
1881 * and before considering the first zone allowed
1884 allowednodes
= zlc_setup(zonelist
, alloc_flags
);
1889 if (zone_reclaim_mode
== 0)
1890 goto this_zone_full
;
1893 * As we may have just activated ZLC, check if the first
1894 * eligible zone has failed zone_reclaim recently.
1896 if (NUMA_BUILD
&& zlc_active
&&
1897 !zlc_zone_worth_trying(zonelist
, z
, allowednodes
))
1900 ret
= zone_reclaim(zone
, gfp_mask
, order
);
1902 case ZONE_RECLAIM_NOSCAN
:
1905 case ZONE_RECLAIM_FULL
:
1906 /* scanned but unreclaimable */
1909 /* did we reclaim enough */
1910 if (!zone_watermark_ok(zone
, order
, mark
,
1911 classzone_idx
, alloc_flags
))
1912 goto this_zone_full
;
1917 page
= buffered_rmqueue(preferred_zone
, zone
, order
,
1918 gfp_mask
, migratetype
);
1923 zlc_mark_zone_full(zonelist
, z
);
1926 if (unlikely(NUMA_BUILD
&& page
== NULL
&& zlc_active
)) {
1927 /* Disable zlc cache for second zonelist scan */
1935 * Large machines with many possible nodes should not always dump per-node
1936 * meminfo in irq context.
1938 static inline bool should_suppress_show_mem(void)
1943 ret
= in_interrupt();
1948 static DEFINE_RATELIMIT_STATE(nopage_rs
,
1949 DEFAULT_RATELIMIT_INTERVAL
,
1950 DEFAULT_RATELIMIT_BURST
);
1952 void warn_alloc_failed(gfp_t gfp_mask
, int order
, const char *fmt
, ...)
1954 unsigned int filter
= SHOW_MEM_FILTER_NODES
;
1956 if ((gfp_mask
& __GFP_NOWARN
) || !__ratelimit(&nopage_rs
) ||
1957 debug_guardpage_minorder() > 0)
1961 * This documents exceptions given to allocations in certain
1962 * contexts that are allowed to allocate outside current's set
1965 if (!(gfp_mask
& __GFP_NOMEMALLOC
))
1966 if (test_thread_flag(TIF_MEMDIE
) ||
1967 (current
->flags
& (PF_MEMALLOC
| PF_EXITING
)))
1968 filter
&= ~SHOW_MEM_FILTER_NODES
;
1969 if (in_interrupt() || !(gfp_mask
& __GFP_WAIT
))
1970 filter
&= ~SHOW_MEM_FILTER_NODES
;
1973 struct va_format vaf
;
1976 va_start(args
, fmt
);
1981 pr_warn("%pV", &vaf
);
1986 pr_warn("%s: page allocation failure: order:%d, mode:0x%x\n",
1987 current
->comm
, order
, gfp_mask
);
1990 if (!should_suppress_show_mem())
1995 should_alloc_retry(gfp_t gfp_mask
, unsigned int order
,
1996 unsigned long did_some_progress
,
1997 unsigned long pages_reclaimed
)
1999 /* Do not loop if specifically requested */
2000 if (gfp_mask
& __GFP_NORETRY
)
2003 /* Always retry if specifically requested */
2004 if (gfp_mask
& __GFP_NOFAIL
)
2008 * Suspend converts GFP_KERNEL to __GFP_WAIT which can prevent reclaim
2009 * making forward progress without invoking OOM. Suspend also disables
2010 * storage devices so kswapd will not help. Bail if we are suspending.
2012 if (!did_some_progress
&& pm_suspended_storage())
2016 * In this implementation, order <= PAGE_ALLOC_COSTLY_ORDER
2017 * means __GFP_NOFAIL, but that may not be true in other
2020 if (order
<= PAGE_ALLOC_COSTLY_ORDER
)
2024 * For order > PAGE_ALLOC_COSTLY_ORDER, if __GFP_REPEAT is
2025 * specified, then we retry until we no longer reclaim any pages
2026 * (above), or we've reclaimed an order of pages at least as
2027 * large as the allocation's order. In both cases, if the
2028 * allocation still fails, we stop retrying.
2030 if (gfp_mask
& __GFP_REPEAT
&& pages_reclaimed
< (1 << order
))
2036 static inline struct page
*
2037 __alloc_pages_may_oom(gfp_t gfp_mask
, unsigned int order
,
2038 struct zonelist
*zonelist
, enum zone_type high_zoneidx
,
2039 nodemask_t
*nodemask
, struct zone
*preferred_zone
,
2044 /* Acquire the OOM killer lock for the zones in zonelist */
2045 if (!try_set_zonelist_oom(zonelist
, gfp_mask
)) {
2046 schedule_timeout_uninterruptible(1);
2051 * Go through the zonelist yet one more time, keep very high watermark
2052 * here, this is only to catch a parallel oom killing, we must fail if
2053 * we're still under heavy pressure.
2055 page
= get_page_from_freelist(gfp_mask
|__GFP_HARDWALL
, nodemask
,
2056 order
, zonelist
, high_zoneidx
,
2057 ALLOC_WMARK_HIGH
|ALLOC_CPUSET
,
2058 preferred_zone
, migratetype
);
2062 if (!(gfp_mask
& __GFP_NOFAIL
)) {
2063 /* The OOM killer will not help higher order allocs */
2064 if (order
> PAGE_ALLOC_COSTLY_ORDER
)
2066 /* The OOM killer does not needlessly kill tasks for lowmem */
2067 if (high_zoneidx
< ZONE_NORMAL
)
2070 * GFP_THISNODE contains __GFP_NORETRY and we never hit this.
2071 * Sanity check for bare calls of __GFP_THISNODE, not real OOM.
2072 * The caller should handle page allocation failure by itself if
2073 * it specifies __GFP_THISNODE.
2074 * Note: Hugepage uses it but will hit PAGE_ALLOC_COSTLY_ORDER.
2076 if (gfp_mask
& __GFP_THISNODE
)
2079 /* Exhausted what can be done so it's blamo time */
2080 out_of_memory(zonelist
, gfp_mask
, order
, nodemask
, false);
2083 clear_zonelist_oom(zonelist
, gfp_mask
);
2087 #ifdef CONFIG_COMPACTION
2088 /* Try memory compaction for high-order allocations before reclaim */
2089 static struct page
*
2090 __alloc_pages_direct_compact(gfp_t gfp_mask
, unsigned int order
,
2091 struct zonelist
*zonelist
, enum zone_type high_zoneidx
,
2092 nodemask_t
*nodemask
, int alloc_flags
, struct zone
*preferred_zone
,
2093 int migratetype
, bool sync_migration
,
2094 bool *deferred_compaction
,
2095 unsigned long *did_some_progress
)
2102 if (compaction_deferred(preferred_zone
, order
)) {
2103 *deferred_compaction
= true;
2107 current
->flags
|= PF_MEMALLOC
;
2108 *did_some_progress
= try_to_compact_pages(zonelist
, order
, gfp_mask
,
2109 nodemask
, sync_migration
);
2110 current
->flags
&= ~PF_MEMALLOC
;
2111 if (*did_some_progress
!= COMPACT_SKIPPED
) {
2113 /* Page migration frees to the PCP lists but we want merging */
2114 drain_pages(get_cpu());
2117 page
= get_page_from_freelist(gfp_mask
, nodemask
,
2118 order
, zonelist
, high_zoneidx
,
2119 alloc_flags
& ~ALLOC_NO_WATERMARKS
,
2120 preferred_zone
, migratetype
);
2122 preferred_zone
->compact_considered
= 0;
2123 preferred_zone
->compact_defer_shift
= 0;
2124 if (order
>= preferred_zone
->compact_order_failed
)
2125 preferred_zone
->compact_order_failed
= order
+ 1;
2126 count_vm_event(COMPACTSUCCESS
);
2131 * It's bad if compaction run occurs and fails.
2132 * The most likely reason is that pages exist,
2133 * but not enough to satisfy watermarks.
2135 count_vm_event(COMPACTFAIL
);
2138 * As async compaction considers a subset of pageblocks, only
2139 * defer if the failure was a sync compaction failure.
2142 defer_compaction(preferred_zone
, order
);
2150 static inline struct page
*
2151 __alloc_pages_direct_compact(gfp_t gfp_mask
, unsigned int order
,
2152 struct zonelist
*zonelist
, enum zone_type high_zoneidx
,
2153 nodemask_t
*nodemask
, int alloc_flags
, struct zone
*preferred_zone
,
2154 int migratetype
, bool sync_migration
,
2155 bool *deferred_compaction
,
2156 unsigned long *did_some_progress
)
2160 #endif /* CONFIG_COMPACTION */
2162 /* Perform direct synchronous page reclaim */
2164 __perform_reclaim(gfp_t gfp_mask
, unsigned int order
, struct zonelist
*zonelist
,
2165 nodemask_t
*nodemask
)
2167 struct reclaim_state reclaim_state
;
2172 /* We now go into synchronous reclaim */
2173 cpuset_memory_pressure_bump();
2174 current
->flags
|= PF_MEMALLOC
;
2175 lockdep_set_current_reclaim_state(gfp_mask
);
2176 reclaim_state
.reclaimed_slab
= 0;
2177 current
->reclaim_state
= &reclaim_state
;
2179 progress
= try_to_free_pages(zonelist
, order
, gfp_mask
, nodemask
);
2181 current
->reclaim_state
= NULL
;
2182 lockdep_clear_current_reclaim_state();
2183 current
->flags
&= ~PF_MEMALLOC
;
2190 /* The really slow allocator path where we enter direct reclaim */
2191 static inline struct page
*
2192 __alloc_pages_direct_reclaim(gfp_t gfp_mask
, unsigned int order
,
2193 struct zonelist
*zonelist
, enum zone_type high_zoneidx
,
2194 nodemask_t
*nodemask
, int alloc_flags
, struct zone
*preferred_zone
,
2195 int migratetype
, unsigned long *did_some_progress
)
2197 struct page
*page
= NULL
;
2198 bool drained
= false;
2200 *did_some_progress
= __perform_reclaim(gfp_mask
, order
, zonelist
,
2202 if (unlikely(!(*did_some_progress
)))
2205 /* After successful reclaim, reconsider all zones for allocation */
2207 zlc_clear_zones_full(zonelist
);
2210 page
= get_page_from_freelist(gfp_mask
, nodemask
, order
,
2211 zonelist
, high_zoneidx
,
2212 alloc_flags
& ~ALLOC_NO_WATERMARKS
,
2213 preferred_zone
, migratetype
);
2216 * If an allocation failed after direct reclaim, it could be because
2217 * pages are pinned on the per-cpu lists. Drain them and try again
2219 if (!page
&& !drained
) {
2229 * This is called in the allocator slow-path if the allocation request is of
2230 * sufficient urgency to ignore watermarks and take other desperate measures
2232 static inline struct page
*
2233 __alloc_pages_high_priority(gfp_t gfp_mask
, unsigned int order
,
2234 struct zonelist
*zonelist
, enum zone_type high_zoneidx
,
2235 nodemask_t
*nodemask
, struct zone
*preferred_zone
,
2241 page
= get_page_from_freelist(gfp_mask
, nodemask
, order
,
2242 zonelist
, high_zoneidx
, ALLOC_NO_WATERMARKS
,
2243 preferred_zone
, migratetype
);
2245 if (!page
&& gfp_mask
& __GFP_NOFAIL
)
2246 wait_iff_congested(preferred_zone
, BLK_RW_ASYNC
, HZ
/50);
2247 } while (!page
&& (gfp_mask
& __GFP_NOFAIL
));
2253 void wake_all_kswapd(unsigned int order
, struct zonelist
*zonelist
,
2254 enum zone_type high_zoneidx
,
2255 enum zone_type classzone_idx
)
2260 for_each_zone_zonelist(zone
, z
, zonelist
, high_zoneidx
)
2261 wakeup_kswapd(zone
, order
, classzone_idx
);
2265 gfp_to_alloc_flags(gfp_t gfp_mask
)
2267 int alloc_flags
= ALLOC_WMARK_MIN
| ALLOC_CPUSET
;
2268 const gfp_t wait
= gfp_mask
& __GFP_WAIT
;
2270 /* __GFP_HIGH is assumed to be the same as ALLOC_HIGH to save a branch. */
2271 BUILD_BUG_ON(__GFP_HIGH
!= (__force gfp_t
) ALLOC_HIGH
);
2274 * The caller may dip into page reserves a bit more if the caller
2275 * cannot run direct reclaim, or if the caller has realtime scheduling
2276 * policy or is asking for __GFP_HIGH memory. GFP_ATOMIC requests will
2277 * set both ALLOC_HARDER (!wait) and ALLOC_HIGH (__GFP_HIGH).
2279 alloc_flags
|= (__force
int) (gfp_mask
& __GFP_HIGH
);
2283 * Not worth trying to allocate harder for
2284 * __GFP_NOMEMALLOC even if it can't schedule.
2286 if (!(gfp_mask
& __GFP_NOMEMALLOC
))
2287 alloc_flags
|= ALLOC_HARDER
;
2289 * Ignore cpuset if GFP_ATOMIC (!wait) rather than fail alloc.
2290 * See also cpuset_zone_allowed() comment in kernel/cpuset.c.
2292 alloc_flags
&= ~ALLOC_CPUSET
;
2293 } else if (unlikely(rt_task(current
)) && !in_interrupt())
2294 alloc_flags
|= ALLOC_HARDER
;
2296 if (likely(!(gfp_mask
& __GFP_NOMEMALLOC
))) {
2297 if (gfp_mask
& __GFP_MEMALLOC
)
2298 alloc_flags
|= ALLOC_NO_WATERMARKS
;
2299 else if (in_serving_softirq() && (current
->flags
& PF_MEMALLOC
))
2300 alloc_flags
|= ALLOC_NO_WATERMARKS
;
2301 else if (!in_interrupt() &&
2302 ((current
->flags
& PF_MEMALLOC
) ||
2303 unlikely(test_thread_flag(TIF_MEMDIE
))))
2304 alloc_flags
|= ALLOC_NO_WATERMARKS
;
2310 bool gfp_pfmemalloc_allowed(gfp_t gfp_mask
)
2312 return !!(gfp_to_alloc_flags(gfp_mask
) & ALLOC_NO_WATERMARKS
);
2315 static inline struct page
*
2316 __alloc_pages_slowpath(gfp_t gfp_mask
, unsigned int order
,
2317 struct zonelist
*zonelist
, enum zone_type high_zoneidx
,
2318 nodemask_t
*nodemask
, struct zone
*preferred_zone
,
2321 const gfp_t wait
= gfp_mask
& __GFP_WAIT
;
2322 struct page
*page
= NULL
;
2324 unsigned long pages_reclaimed
= 0;
2325 unsigned long did_some_progress
;
2326 bool sync_migration
= false;
2327 bool deferred_compaction
= false;
2330 * In the slowpath, we sanity check order to avoid ever trying to
2331 * reclaim >= MAX_ORDER areas which will never succeed. Callers may
2332 * be using allocators in order of preference for an area that is
2335 if (order
>= MAX_ORDER
) {
2336 WARN_ON_ONCE(!(gfp_mask
& __GFP_NOWARN
));
2341 * GFP_THISNODE (meaning __GFP_THISNODE, __GFP_NORETRY and
2342 * __GFP_NOWARN set) should not cause reclaim since the subsystem
2343 * (f.e. slab) using GFP_THISNODE may choose to trigger reclaim
2344 * using a larger set of nodes after it has established that the
2345 * allowed per node queues are empty and that nodes are
2348 if (NUMA_BUILD
&& (gfp_mask
& GFP_THISNODE
) == GFP_THISNODE
)
2352 if (!(gfp_mask
& __GFP_NO_KSWAPD
))
2353 wake_all_kswapd(order
, zonelist
, high_zoneidx
,
2354 zone_idx(preferred_zone
));
2357 * OK, we're below the kswapd watermark and have kicked background
2358 * reclaim. Now things get more complex, so set up alloc_flags according
2359 * to how we want to proceed.
2361 alloc_flags
= gfp_to_alloc_flags(gfp_mask
);
2364 * Find the true preferred zone if the allocation is unconstrained by
2367 if (!(alloc_flags
& ALLOC_CPUSET
) && !nodemask
)
2368 first_zones_zonelist(zonelist
, high_zoneidx
, NULL
,
2372 /* This is the last chance, in general, before the goto nopage. */
2373 page
= get_page_from_freelist(gfp_mask
, nodemask
, order
, zonelist
,
2374 high_zoneidx
, alloc_flags
& ~ALLOC_NO_WATERMARKS
,
2375 preferred_zone
, migratetype
);
2379 /* Allocate without watermarks if the context allows */
2380 if (alloc_flags
& ALLOC_NO_WATERMARKS
) {
2382 * Ignore mempolicies if ALLOC_NO_WATERMARKS on the grounds
2383 * the allocation is high priority and these type of
2384 * allocations are system rather than user orientated
2386 zonelist
= node_zonelist(numa_node_id(), gfp_mask
);
2388 page
= __alloc_pages_high_priority(gfp_mask
, order
,
2389 zonelist
, high_zoneidx
, nodemask
,
2390 preferred_zone
, migratetype
);
2393 * page->pfmemalloc is set when ALLOC_NO_WATERMARKS was
2394 * necessary to allocate the page. The expectation is
2395 * that the caller is taking steps that will free more
2396 * memory. The caller should avoid the page being used
2397 * for !PFMEMALLOC purposes.
2399 page
->pfmemalloc
= true;
2404 /* Atomic allocations - we can't balance anything */
2408 /* Avoid recursion of direct reclaim */
2409 if (current
->flags
& PF_MEMALLOC
)
2412 /* Avoid allocations with no watermarks from looping endlessly */
2413 if (test_thread_flag(TIF_MEMDIE
) && !(gfp_mask
& __GFP_NOFAIL
))
2417 * Try direct compaction. The first pass is asynchronous. Subsequent
2418 * attempts after direct reclaim are synchronous
2420 page
= __alloc_pages_direct_compact(gfp_mask
, order
,
2421 zonelist
, high_zoneidx
,
2423 alloc_flags
, preferred_zone
,
2424 migratetype
, sync_migration
,
2425 &deferred_compaction
,
2426 &did_some_progress
);
2429 sync_migration
= true;
2432 * If compaction is deferred for high-order allocations, it is because
2433 * sync compaction recently failed. In this is the case and the caller
2434 * has requested the system not be heavily disrupted, fail the
2435 * allocation now instead of entering direct reclaim
2437 if (deferred_compaction
&& (gfp_mask
& __GFP_NO_KSWAPD
))
2440 /* Try direct reclaim and then allocating */
2441 page
= __alloc_pages_direct_reclaim(gfp_mask
, order
,
2442 zonelist
, high_zoneidx
,
2444 alloc_flags
, preferred_zone
,
2445 migratetype
, &did_some_progress
);
2450 * If we failed to make any progress reclaiming, then we are
2451 * running out of options and have to consider going OOM
2453 if (!did_some_progress
) {
2454 if ((gfp_mask
& __GFP_FS
) && !(gfp_mask
& __GFP_NORETRY
)) {
2455 if (oom_killer_disabled
)
2457 /* Coredumps can quickly deplete all memory reserves */
2458 if ((current
->flags
& PF_DUMPCORE
) &&
2459 !(gfp_mask
& __GFP_NOFAIL
))
2461 page
= __alloc_pages_may_oom(gfp_mask
, order
,
2462 zonelist
, high_zoneidx
,
2463 nodemask
, preferred_zone
,
2468 if (!(gfp_mask
& __GFP_NOFAIL
)) {
2470 * The oom killer is not called for high-order
2471 * allocations that may fail, so if no progress
2472 * is being made, there are no other options and
2473 * retrying is unlikely to help.
2475 if (order
> PAGE_ALLOC_COSTLY_ORDER
)
2478 * The oom killer is not called for lowmem
2479 * allocations to prevent needlessly killing
2482 if (high_zoneidx
< ZONE_NORMAL
)
2490 /* Check if we should retry the allocation */
2491 pages_reclaimed
+= did_some_progress
;
2492 if (should_alloc_retry(gfp_mask
, order
, did_some_progress
,
2494 /* Wait for some write requests to complete then retry */
2495 wait_iff_congested(preferred_zone
, BLK_RW_ASYNC
, HZ
/50);
2499 * High-order allocations do not necessarily loop after
2500 * direct reclaim and reclaim/compaction depends on compaction
2501 * being called after reclaim so call directly if necessary
2503 page
= __alloc_pages_direct_compact(gfp_mask
, order
,
2504 zonelist
, high_zoneidx
,
2506 alloc_flags
, preferred_zone
,
2507 migratetype
, sync_migration
,
2508 &deferred_compaction
,
2509 &did_some_progress
);
2515 warn_alloc_failed(gfp_mask
, order
, NULL
);
2518 if (kmemcheck_enabled
)
2519 kmemcheck_pagealloc_alloc(page
, order
, gfp_mask
);
2525 * This is the 'heart' of the zoned buddy allocator.
2528 __alloc_pages_nodemask(gfp_t gfp_mask
, unsigned int order
,
2529 struct zonelist
*zonelist
, nodemask_t
*nodemask
)
2531 enum zone_type high_zoneidx
= gfp_zone(gfp_mask
);
2532 struct zone
*preferred_zone
;
2533 struct page
*page
= NULL
;
2534 int migratetype
= allocflags_to_migratetype(gfp_mask
);
2535 unsigned int cpuset_mems_cookie
;
2537 gfp_mask
&= gfp_allowed_mask
;
2539 lockdep_trace_alloc(gfp_mask
);
2541 might_sleep_if(gfp_mask
& __GFP_WAIT
);
2543 if (should_fail_alloc_page(gfp_mask
, order
))
2547 * Check the zones suitable for the gfp_mask contain at least one
2548 * valid zone. It's possible to have an empty zonelist as a result
2549 * of GFP_THISNODE and a memoryless node
2551 if (unlikely(!zonelist
->_zonerefs
->zone
))
2555 cpuset_mems_cookie
= get_mems_allowed();
2557 /* The preferred zone is used for statistics later */
2558 first_zones_zonelist(zonelist
, high_zoneidx
,
2559 nodemask
? : &cpuset_current_mems_allowed
,
2561 if (!preferred_zone
)
2564 /* First allocation attempt */
2565 page
= get_page_from_freelist(gfp_mask
|__GFP_HARDWALL
, nodemask
, order
,
2566 zonelist
, high_zoneidx
, ALLOC_WMARK_LOW
|ALLOC_CPUSET
,
2567 preferred_zone
, migratetype
);
2568 if (unlikely(!page
))
2569 page
= __alloc_pages_slowpath(gfp_mask
, order
,
2570 zonelist
, high_zoneidx
, nodemask
,
2571 preferred_zone
, migratetype
);
2573 page
->pfmemalloc
= false;
2575 trace_mm_page_alloc(page
, order
, gfp_mask
, migratetype
);
2579 * When updating a task's mems_allowed, it is possible to race with
2580 * parallel threads in such a way that an allocation can fail while
2581 * the mask is being updated. If a page allocation is about to fail,
2582 * check if the cpuset changed during allocation and if so, retry.
2584 if (unlikely(!put_mems_allowed(cpuset_mems_cookie
) && !page
))
2589 EXPORT_SYMBOL(__alloc_pages_nodemask
);
2592 * Common helper functions.
2594 unsigned long __get_free_pages(gfp_t gfp_mask
, unsigned int order
)
2599 * __get_free_pages() returns a 32-bit address, which cannot represent
2602 VM_BUG_ON((gfp_mask
& __GFP_HIGHMEM
) != 0);
2604 page
= alloc_pages(gfp_mask
, order
);
2607 return (unsigned long) page_address(page
);
2609 EXPORT_SYMBOL(__get_free_pages
);
2611 unsigned long get_zeroed_page(gfp_t gfp_mask
)
2613 return __get_free_pages(gfp_mask
| __GFP_ZERO
, 0);
2615 EXPORT_SYMBOL(get_zeroed_page
);
2617 void __free_pages(struct page
*page
, unsigned int order
)
2619 if (put_page_testzero(page
)) {
2621 free_hot_cold_page(page
, 0);
2623 __free_pages_ok(page
, order
);
2627 EXPORT_SYMBOL(__free_pages
);
2629 void free_pages(unsigned long addr
, unsigned int order
)
2632 VM_BUG_ON(!virt_addr_valid((void *)addr
));
2633 __free_pages(virt_to_page((void *)addr
), order
);
2637 EXPORT_SYMBOL(free_pages
);
2639 static void *make_alloc_exact(unsigned long addr
, unsigned order
, size_t size
)
2642 unsigned long alloc_end
= addr
+ (PAGE_SIZE
<< order
);
2643 unsigned long used
= addr
+ PAGE_ALIGN(size
);
2645 split_page(virt_to_page((void *)addr
), order
);
2646 while (used
< alloc_end
) {
2651 return (void *)addr
;
2655 * alloc_pages_exact - allocate an exact number physically-contiguous pages.
2656 * @size: the number of bytes to allocate
2657 * @gfp_mask: GFP flags for the allocation
2659 * This function is similar to alloc_pages(), except that it allocates the
2660 * minimum number of pages to satisfy the request. alloc_pages() can only
2661 * allocate memory in power-of-two pages.
2663 * This function is also limited by MAX_ORDER.
2665 * Memory allocated by this function must be released by free_pages_exact().
2667 void *alloc_pages_exact(size_t size
, gfp_t gfp_mask
)
2669 unsigned int order
= get_order(size
);
2672 addr
= __get_free_pages(gfp_mask
, order
);
2673 return make_alloc_exact(addr
, order
, size
);
2675 EXPORT_SYMBOL(alloc_pages_exact
);
2678 * alloc_pages_exact_nid - allocate an exact number of physically-contiguous
2680 * @nid: the preferred node ID where memory should be allocated
2681 * @size: the number of bytes to allocate
2682 * @gfp_mask: GFP flags for the allocation
2684 * Like alloc_pages_exact(), but try to allocate on node nid first before falling
2686 * Note this is not alloc_pages_exact_node() which allocates on a specific node,
2689 void *alloc_pages_exact_nid(int nid
, size_t size
, gfp_t gfp_mask
)
2691 unsigned order
= get_order(size
);
2692 struct page
*p
= alloc_pages_node(nid
, gfp_mask
, order
);
2695 return make_alloc_exact((unsigned long)page_address(p
), order
, size
);
2697 EXPORT_SYMBOL(alloc_pages_exact_nid
);
2700 * free_pages_exact - release memory allocated via alloc_pages_exact()
2701 * @virt: the value returned by alloc_pages_exact.
2702 * @size: size of allocation, same value as passed to alloc_pages_exact().
2704 * Release the memory allocated by a previous call to alloc_pages_exact.
2706 void free_pages_exact(void *virt
, size_t size
)
2708 unsigned long addr
= (unsigned long)virt
;
2709 unsigned long end
= addr
+ PAGE_ALIGN(size
);
2711 while (addr
< end
) {
2716 EXPORT_SYMBOL(free_pages_exact
);
2718 static unsigned int nr_free_zone_pages(int offset
)
2723 /* Just pick one node, since fallback list is circular */
2724 unsigned int sum
= 0;
2726 struct zonelist
*zonelist
= node_zonelist(numa_node_id(), GFP_KERNEL
);
2728 for_each_zone_zonelist(zone
, z
, zonelist
, offset
) {
2729 unsigned long size
= zone
->present_pages
;
2730 unsigned long high
= high_wmark_pages(zone
);
2739 * Amount of free RAM allocatable within ZONE_DMA and ZONE_NORMAL
2741 unsigned int nr_free_buffer_pages(void)
2743 return nr_free_zone_pages(gfp_zone(GFP_USER
));
2745 EXPORT_SYMBOL_GPL(nr_free_buffer_pages
);
2748 * Amount of free RAM allocatable within all zones
2750 unsigned int nr_free_pagecache_pages(void)
2752 return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE
));
2755 static inline void show_node(struct zone
*zone
)
2758 printk("Node %d ", zone_to_nid(zone
));
2761 void si_meminfo(struct sysinfo
*val
)
2763 val
->totalram
= totalram_pages
;
2765 val
->freeram
= global_page_state(NR_FREE_PAGES
);
2766 val
->bufferram
= nr_blockdev_pages();
2767 val
->totalhigh
= totalhigh_pages
;
2768 val
->freehigh
= nr_free_highpages();
2769 val
->mem_unit
= PAGE_SIZE
;
2772 EXPORT_SYMBOL(si_meminfo
);
2775 void si_meminfo_node(struct sysinfo
*val
, int nid
)
2777 pg_data_t
*pgdat
= NODE_DATA(nid
);
2779 val
->totalram
= pgdat
->node_present_pages
;
2780 val
->freeram
= node_page_state(nid
, NR_FREE_PAGES
);
2781 #ifdef CONFIG_HIGHMEM
2782 val
->totalhigh
= pgdat
->node_zones
[ZONE_HIGHMEM
].present_pages
;
2783 val
->freehigh
= zone_page_state(&pgdat
->node_zones
[ZONE_HIGHMEM
],
2789 val
->mem_unit
= PAGE_SIZE
;
2794 * Determine whether the node should be displayed or not, depending on whether
2795 * SHOW_MEM_FILTER_NODES was passed to show_free_areas().
2797 bool skip_free_areas_node(unsigned int flags
, int nid
)
2800 unsigned int cpuset_mems_cookie
;
2802 if (!(flags
& SHOW_MEM_FILTER_NODES
))
2806 cpuset_mems_cookie
= get_mems_allowed();
2807 ret
= !node_isset(nid
, cpuset_current_mems_allowed
);
2808 } while (!put_mems_allowed(cpuset_mems_cookie
));
2813 #define K(x) ((x) << (PAGE_SHIFT-10))
2816 * Show free area list (used inside shift_scroll-lock stuff)
2817 * We also calculate the percentage fragmentation. We do this by counting the
2818 * memory on each free list with the exception of the first item on the list.
2819 * Suppresses nodes that are not allowed by current's cpuset if
2820 * SHOW_MEM_FILTER_NODES is passed.
2822 void show_free_areas(unsigned int filter
)
2827 for_each_populated_zone(zone
) {
2828 if (skip_free_areas_node(filter
, zone_to_nid(zone
)))
2831 printk("%s per-cpu:\n", zone
->name
);
2833 for_each_online_cpu(cpu
) {
2834 struct per_cpu_pageset
*pageset
;
2836 pageset
= per_cpu_ptr(zone
->pageset
, cpu
);
2838 printk("CPU %4d: hi:%5d, btch:%4d usd:%4d\n",
2839 cpu
, pageset
->pcp
.high
,
2840 pageset
->pcp
.batch
, pageset
->pcp
.count
);
2844 printk("active_anon:%lu inactive_anon:%lu isolated_anon:%lu\n"
2845 " active_file:%lu inactive_file:%lu isolated_file:%lu\n"
2847 " dirty:%lu writeback:%lu unstable:%lu\n"
2848 " free:%lu slab_reclaimable:%lu slab_unreclaimable:%lu\n"
2849 " mapped:%lu shmem:%lu pagetables:%lu bounce:%lu\n",
2850 global_page_state(NR_ACTIVE_ANON
),
2851 global_page_state(NR_INACTIVE_ANON
),
2852 global_page_state(NR_ISOLATED_ANON
),
2853 global_page_state(NR_ACTIVE_FILE
),
2854 global_page_state(NR_INACTIVE_FILE
),
2855 global_page_state(NR_ISOLATED_FILE
),
2856 global_page_state(NR_UNEVICTABLE
),
2857 global_page_state(NR_FILE_DIRTY
),
2858 global_page_state(NR_WRITEBACK
),
2859 global_page_state(NR_UNSTABLE_NFS
),
2860 global_page_state(NR_FREE_PAGES
),
2861 global_page_state(NR_SLAB_RECLAIMABLE
),
2862 global_page_state(NR_SLAB_UNRECLAIMABLE
),
2863 global_page_state(NR_FILE_MAPPED
),
2864 global_page_state(NR_SHMEM
),
2865 global_page_state(NR_PAGETABLE
),
2866 global_page_state(NR_BOUNCE
));
2868 for_each_populated_zone(zone
) {
2871 if (skip_free_areas_node(filter
, zone_to_nid(zone
)))
2879 " active_anon:%lukB"
2880 " inactive_anon:%lukB"
2881 " active_file:%lukB"
2882 " inactive_file:%lukB"
2883 " unevictable:%lukB"
2884 " isolated(anon):%lukB"
2885 " isolated(file):%lukB"
2892 " slab_reclaimable:%lukB"
2893 " slab_unreclaimable:%lukB"
2894 " kernel_stack:%lukB"
2898 " writeback_tmp:%lukB"
2899 " pages_scanned:%lu"
2900 " all_unreclaimable? %s"
2903 K(zone_page_state(zone
, NR_FREE_PAGES
)),
2904 K(min_wmark_pages(zone
)),
2905 K(low_wmark_pages(zone
)),
2906 K(high_wmark_pages(zone
)),
2907 K(zone_page_state(zone
, NR_ACTIVE_ANON
)),
2908 K(zone_page_state(zone
, NR_INACTIVE_ANON
)),
2909 K(zone_page_state(zone
, NR_ACTIVE_FILE
)),
2910 K(zone_page_state(zone
, NR_INACTIVE_FILE
)),
2911 K(zone_page_state(zone
, NR_UNEVICTABLE
)),
2912 K(zone_page_state(zone
, NR_ISOLATED_ANON
)),
2913 K(zone_page_state(zone
, NR_ISOLATED_FILE
)),
2914 K(zone
->present_pages
),
2915 K(zone_page_state(zone
, NR_MLOCK
)),
2916 K(zone_page_state(zone
, NR_FILE_DIRTY
)),
2917 K(zone_page_state(zone
, NR_WRITEBACK
)),
2918 K(zone_page_state(zone
, NR_FILE_MAPPED
)),
2919 K(zone_page_state(zone
, NR_SHMEM
)),
2920 K(zone_page_state(zone
, NR_SLAB_RECLAIMABLE
)),
2921 K(zone_page_state(zone
, NR_SLAB_UNRECLAIMABLE
)),
2922 zone_page_state(zone
, NR_KERNEL_STACK
) *
2924 K(zone_page_state(zone
, NR_PAGETABLE
)),
2925 K(zone_page_state(zone
, NR_UNSTABLE_NFS
)),
2926 K(zone_page_state(zone
, NR_BOUNCE
)),
2927 K(zone_page_state(zone
, NR_WRITEBACK_TEMP
)),
2928 zone
->pages_scanned
,
2929 (zone
->all_unreclaimable
? "yes" : "no")
2931 printk("lowmem_reserve[]:");
2932 for (i
= 0; i
< MAX_NR_ZONES
; i
++)
2933 printk(" %lu", zone
->lowmem_reserve
[i
]);
2937 for_each_populated_zone(zone
) {
2938 unsigned long nr
[MAX_ORDER
], flags
, order
, total
= 0;
2940 if (skip_free_areas_node(filter
, zone_to_nid(zone
)))
2943 printk("%s: ", zone
->name
);
2945 spin_lock_irqsave(&zone
->lock
, flags
);
2946 for (order
= 0; order
< MAX_ORDER
; order
++) {
2947 nr
[order
] = zone
->free_area
[order
].nr_free
;
2948 total
+= nr
[order
] << order
;
2950 spin_unlock_irqrestore(&zone
->lock
, flags
);
2951 for (order
= 0; order
< MAX_ORDER
; order
++)
2952 printk("%lu*%lukB ", nr
[order
], K(1UL) << order
);
2953 printk("= %lukB\n", K(total
));
2956 printk("%ld total pagecache pages\n", global_page_state(NR_FILE_PAGES
));
2958 show_swap_cache_info();
2961 static void zoneref_set_zone(struct zone
*zone
, struct zoneref
*zoneref
)
2963 zoneref
->zone
= zone
;
2964 zoneref
->zone_idx
= zone_idx(zone
);
2968 * Builds allocation fallback zone lists.
2970 * Add all populated zones of a node to the zonelist.
2972 static int build_zonelists_node(pg_data_t
*pgdat
, struct zonelist
*zonelist
,
2973 int nr_zones
, enum zone_type zone_type
)
2977 BUG_ON(zone_type
>= MAX_NR_ZONES
);
2982 zone
= pgdat
->node_zones
+ zone_type
;
2983 if (populated_zone(zone
)) {
2984 zoneref_set_zone(zone
,
2985 &zonelist
->_zonerefs
[nr_zones
++]);
2986 check_highest_zone(zone_type
);
2989 } while (zone_type
);
2996 * 0 = automatic detection of better ordering.
2997 * 1 = order by ([node] distance, -zonetype)
2998 * 2 = order by (-zonetype, [node] distance)
3000 * If not NUMA, ZONELIST_ORDER_ZONE and ZONELIST_ORDER_NODE will create
3001 * the same zonelist. So only NUMA can configure this param.
3003 #define ZONELIST_ORDER_DEFAULT 0
3004 #define ZONELIST_ORDER_NODE 1
3005 #define ZONELIST_ORDER_ZONE 2
3007 /* zonelist order in the kernel.
3008 * set_zonelist_order() will set this to NODE or ZONE.
3010 static int current_zonelist_order
= ZONELIST_ORDER_DEFAULT
;
3011 static char zonelist_order_name
[3][8] = {"Default", "Node", "Zone"};
3015 /* The value user specified ....changed by config */
3016 static int user_zonelist_order
= ZONELIST_ORDER_DEFAULT
;
3017 /* string for sysctl */
3018 #define NUMA_ZONELIST_ORDER_LEN 16
3019 char numa_zonelist_order
[16] = "default";
3022 * interface for configure zonelist ordering.
3023 * command line option "numa_zonelist_order"
3024 * = "[dD]efault - default, automatic configuration.
3025 * = "[nN]ode - order by node locality, then by zone within node
3026 * = "[zZ]one - order by zone, then by locality within zone
3029 static int __parse_numa_zonelist_order(char *s
)
3031 if (*s
== 'd' || *s
== 'D') {
3032 user_zonelist_order
= ZONELIST_ORDER_DEFAULT
;
3033 } else if (*s
== 'n' || *s
== 'N') {
3034 user_zonelist_order
= ZONELIST_ORDER_NODE
;
3035 } else if (*s
== 'z' || *s
== 'Z') {
3036 user_zonelist_order
= ZONELIST_ORDER_ZONE
;
3039 "Ignoring invalid numa_zonelist_order value: "
3046 static __init
int setup_numa_zonelist_order(char *s
)
3053 ret
= __parse_numa_zonelist_order(s
);
3055 strlcpy(numa_zonelist_order
, s
, NUMA_ZONELIST_ORDER_LEN
);
3059 early_param("numa_zonelist_order", setup_numa_zonelist_order
);
3062 * sysctl handler for numa_zonelist_order
3064 int numa_zonelist_order_handler(ctl_table
*table
, int write
,
3065 void __user
*buffer
, size_t *length
,
3068 char saved_string
[NUMA_ZONELIST_ORDER_LEN
];
3070 static DEFINE_MUTEX(zl_order_mutex
);
3072 mutex_lock(&zl_order_mutex
);
3074 strcpy(saved_string
, (char*)table
->data
);
3075 ret
= proc_dostring(table
, write
, buffer
, length
, ppos
);
3079 int oldval
= user_zonelist_order
;
3080 if (__parse_numa_zonelist_order((char*)table
->data
)) {
3082 * bogus value. restore saved string
3084 strncpy((char*)table
->data
, saved_string
,
3085 NUMA_ZONELIST_ORDER_LEN
);
3086 user_zonelist_order
= oldval
;
3087 } else if (oldval
!= user_zonelist_order
) {
3088 mutex_lock(&zonelists_mutex
);
3089 build_all_zonelists(NULL
, NULL
);
3090 mutex_unlock(&zonelists_mutex
);
3094 mutex_unlock(&zl_order_mutex
);
3099 #define MAX_NODE_LOAD (nr_online_nodes)
3100 static int node_load
[MAX_NUMNODES
];
3103 * find_next_best_node - find the next node that should appear in a given node's fallback list
3104 * @node: node whose fallback list we're appending
3105 * @used_node_mask: nodemask_t of already used nodes
3107 * We use a number of factors to determine which is the next node that should
3108 * appear on a given node's fallback list. The node should not have appeared
3109 * already in @node's fallback list, and it should be the next closest node
3110 * according to the distance array (which contains arbitrary distance values
3111 * from each node to each node in the system), and should also prefer nodes
3112 * with no CPUs, since presumably they'll have very little allocation pressure
3113 * on them otherwise.
3114 * It returns -1 if no node is found.
3116 static int find_next_best_node(int node
, nodemask_t
*used_node_mask
)
3119 int min_val
= INT_MAX
;
3121 const struct cpumask
*tmp
= cpumask_of_node(0);
3123 /* Use the local node if we haven't already */
3124 if (!node_isset(node
, *used_node_mask
)) {
3125 node_set(node
, *used_node_mask
);
3129 for_each_node_state(n
, N_HIGH_MEMORY
) {
3131 /* Don't want a node to appear more than once */
3132 if (node_isset(n
, *used_node_mask
))
3135 /* Use the distance array to find the distance */
3136 val
= node_distance(node
, n
);
3138 /* Penalize nodes under us ("prefer the next node") */
3141 /* Give preference to headless and unused nodes */
3142 tmp
= cpumask_of_node(n
);
3143 if (!cpumask_empty(tmp
))
3144 val
+= PENALTY_FOR_NODE_WITH_CPUS
;
3146 /* Slight preference for less loaded node */
3147 val
*= (MAX_NODE_LOAD
*MAX_NUMNODES
);
3148 val
+= node_load
[n
];
3150 if (val
< min_val
) {
3157 node_set(best_node
, *used_node_mask
);
3164 * Build zonelists ordered by node and zones within node.
3165 * This results in maximum locality--normal zone overflows into local
3166 * DMA zone, if any--but risks exhausting DMA zone.
3168 static void build_zonelists_in_node_order(pg_data_t
*pgdat
, int node
)
3171 struct zonelist
*zonelist
;
3173 zonelist
= &pgdat
->node_zonelists
[0];
3174 for (j
= 0; zonelist
->_zonerefs
[j
].zone
!= NULL
; j
++)
3176 j
= build_zonelists_node(NODE_DATA(node
), zonelist
, j
,
3178 zonelist
->_zonerefs
[j
].zone
= NULL
;
3179 zonelist
->_zonerefs
[j
].zone_idx
= 0;
3183 * Build gfp_thisnode zonelists
3185 static void build_thisnode_zonelists(pg_data_t
*pgdat
)
3188 struct zonelist
*zonelist
;
3190 zonelist
= &pgdat
->node_zonelists
[1];
3191 j
= build_zonelists_node(pgdat
, zonelist
, 0, MAX_NR_ZONES
- 1);
3192 zonelist
->_zonerefs
[j
].zone
= NULL
;
3193 zonelist
->_zonerefs
[j
].zone_idx
= 0;
3197 * Build zonelists ordered by zone and nodes within zones.
3198 * This results in conserving DMA zone[s] until all Normal memory is
3199 * exhausted, but results in overflowing to remote node while memory
3200 * may still exist in local DMA zone.
3202 static int node_order
[MAX_NUMNODES
];
3204 static void build_zonelists_in_zone_order(pg_data_t
*pgdat
, int nr_nodes
)
3207 int zone_type
; /* needs to be signed */
3209 struct zonelist
*zonelist
;
3211 zonelist
= &pgdat
->node_zonelists
[0];
3213 for (zone_type
= MAX_NR_ZONES
- 1; zone_type
>= 0; zone_type
--) {
3214 for (j
= 0; j
< nr_nodes
; j
++) {
3215 node
= node_order
[j
];
3216 z
= &NODE_DATA(node
)->node_zones
[zone_type
];
3217 if (populated_zone(z
)) {
3219 &zonelist
->_zonerefs
[pos
++]);
3220 check_highest_zone(zone_type
);
3224 zonelist
->_zonerefs
[pos
].zone
= NULL
;
3225 zonelist
->_zonerefs
[pos
].zone_idx
= 0;
3228 static int default_zonelist_order(void)
3231 unsigned long low_kmem_size
,total_size
;
3235 * ZONE_DMA and ZONE_DMA32 can be very small area in the system.
3236 * If they are really small and used heavily, the system can fall
3237 * into OOM very easily.
3238 * This function detect ZONE_DMA/DMA32 size and configures zone order.
3240 /* Is there ZONE_NORMAL ? (ex. ppc has only DMA zone..) */
3243 for_each_online_node(nid
) {
3244 for (zone_type
= 0; zone_type
< MAX_NR_ZONES
; zone_type
++) {
3245 z
= &NODE_DATA(nid
)->node_zones
[zone_type
];
3246 if (populated_zone(z
)) {
3247 if (zone_type
< ZONE_NORMAL
)
3248 low_kmem_size
+= z
->present_pages
;
3249 total_size
+= z
->present_pages
;
3250 } else if (zone_type
== ZONE_NORMAL
) {
3252 * If any node has only lowmem, then node order
3253 * is preferred to allow kernel allocations
3254 * locally; otherwise, they can easily infringe
3255 * on other nodes when there is an abundance of
3256 * lowmem available to allocate from.
3258 return ZONELIST_ORDER_NODE
;
3262 if (!low_kmem_size
|| /* there are no DMA area. */
3263 low_kmem_size
> total_size
/2) /* DMA/DMA32 is big. */
3264 return ZONELIST_ORDER_NODE
;
3266 * look into each node's config.
3267 * If there is a node whose DMA/DMA32 memory is very big area on
3268 * local memory, NODE_ORDER may be suitable.
3270 average_size
= total_size
/
3271 (nodes_weight(node_states
[N_HIGH_MEMORY
]) + 1);
3272 for_each_online_node(nid
) {
3275 for (zone_type
= 0; zone_type
< MAX_NR_ZONES
; zone_type
++) {
3276 z
= &NODE_DATA(nid
)->node_zones
[zone_type
];
3277 if (populated_zone(z
)) {
3278 if (zone_type
< ZONE_NORMAL
)
3279 low_kmem_size
+= z
->present_pages
;
3280 total_size
+= z
->present_pages
;
3283 if (low_kmem_size
&&
3284 total_size
> average_size
&& /* ignore small node */
3285 low_kmem_size
> total_size
* 70/100)
3286 return ZONELIST_ORDER_NODE
;
3288 return ZONELIST_ORDER_ZONE
;
3291 static void set_zonelist_order(void)
3293 if (user_zonelist_order
== ZONELIST_ORDER_DEFAULT
)
3294 current_zonelist_order
= default_zonelist_order();
3296 current_zonelist_order
= user_zonelist_order
;
3299 static void build_zonelists(pg_data_t
*pgdat
)
3303 nodemask_t used_mask
;
3304 int local_node
, prev_node
;
3305 struct zonelist
*zonelist
;
3306 int order
= current_zonelist_order
;
3308 /* initialize zonelists */
3309 for (i
= 0; i
< MAX_ZONELISTS
; i
++) {
3310 zonelist
= pgdat
->node_zonelists
+ i
;
3311 zonelist
->_zonerefs
[0].zone
= NULL
;
3312 zonelist
->_zonerefs
[0].zone_idx
= 0;
3315 /* NUMA-aware ordering of nodes */
3316 local_node
= pgdat
->node_id
;
3317 load
= nr_online_nodes
;
3318 prev_node
= local_node
;
3319 nodes_clear(used_mask
);
3321 memset(node_order
, 0, sizeof(node_order
));
3324 while ((node
= find_next_best_node(local_node
, &used_mask
)) >= 0) {
3325 int distance
= node_distance(local_node
, node
);
3328 * If another node is sufficiently far away then it is better
3329 * to reclaim pages in a zone before going off node.
3331 if (distance
> RECLAIM_DISTANCE
)
3332 zone_reclaim_mode
= 1;
3335 * We don't want to pressure a particular node.
3336 * So adding penalty to the first node in same
3337 * distance group to make it round-robin.
3339 if (distance
!= node_distance(local_node
, prev_node
))
3340 node_load
[node
] = load
;
3344 if (order
== ZONELIST_ORDER_NODE
)
3345 build_zonelists_in_node_order(pgdat
, node
);
3347 node_order
[j
++] = node
; /* remember order */
3350 if (order
== ZONELIST_ORDER_ZONE
) {
3351 /* calculate node order -- i.e., DMA last! */
3352 build_zonelists_in_zone_order(pgdat
, j
);
3355 build_thisnode_zonelists(pgdat
);
3358 /* Construct the zonelist performance cache - see further mmzone.h */
3359 static void build_zonelist_cache(pg_data_t
*pgdat
)
3361 struct zonelist
*zonelist
;
3362 struct zonelist_cache
*zlc
;
3365 zonelist
= &pgdat
->node_zonelists
[0];
3366 zonelist
->zlcache_ptr
= zlc
= &zonelist
->zlcache
;
3367 bitmap_zero(zlc
->fullzones
, MAX_ZONES_PER_ZONELIST
);
3368 for (z
= zonelist
->_zonerefs
; z
->zone
; z
++)
3369 zlc
->z_to_n
[z
- zonelist
->_zonerefs
] = zonelist_node_idx(z
);
3372 #ifdef CONFIG_HAVE_MEMORYLESS_NODES
3374 * Return node id of node used for "local" allocations.
3375 * I.e., first node id of first zone in arg node's generic zonelist.
3376 * Used for initializing percpu 'numa_mem', which is used primarily
3377 * for kernel allocations, so use GFP_KERNEL flags to locate zonelist.
3379 int local_memory_node(int node
)
3383 (void)first_zones_zonelist(node_zonelist(node
, GFP_KERNEL
),
3384 gfp_zone(GFP_KERNEL
),
3391 #else /* CONFIG_NUMA */
3393 static void set_zonelist_order(void)
3395 current_zonelist_order
= ZONELIST_ORDER_ZONE
;
3398 static void build_zonelists(pg_data_t
*pgdat
)
3400 int node
, local_node
;
3402 struct zonelist
*zonelist
;
3404 local_node
= pgdat
->node_id
;
3406 zonelist
= &pgdat
->node_zonelists
[0];
3407 j
= build_zonelists_node(pgdat
, zonelist
, 0, MAX_NR_ZONES
- 1);
3410 * Now we build the zonelist so that it contains the zones
3411 * of all the other nodes.
3412 * We don't want to pressure a particular node, so when
3413 * building the zones for node N, we make sure that the
3414 * zones coming right after the local ones are those from
3415 * node N+1 (modulo N)
3417 for (node
= local_node
+ 1; node
< MAX_NUMNODES
; node
++) {
3418 if (!node_online(node
))
3420 j
= build_zonelists_node(NODE_DATA(node
), zonelist
, j
,
3423 for (node
= 0; node
< local_node
; node
++) {
3424 if (!node_online(node
))
3426 j
= build_zonelists_node(NODE_DATA(node
), zonelist
, j
,
3430 zonelist
->_zonerefs
[j
].zone
= NULL
;
3431 zonelist
->_zonerefs
[j
].zone_idx
= 0;
3434 /* non-NUMA variant of zonelist performance cache - just NULL zlcache_ptr */
3435 static void build_zonelist_cache(pg_data_t
*pgdat
)
3437 pgdat
->node_zonelists
[0].zlcache_ptr
= NULL
;
3440 #endif /* CONFIG_NUMA */
3443 * Boot pageset table. One per cpu which is going to be used for all
3444 * zones and all nodes. The parameters will be set in such a way
3445 * that an item put on a list will immediately be handed over to
3446 * the buddy list. This is safe since pageset manipulation is done
3447 * with interrupts disabled.
3449 * The boot_pagesets must be kept even after bootup is complete for
3450 * unused processors and/or zones. They do play a role for bootstrapping
3451 * hotplugged processors.
3453 * zoneinfo_show() and maybe other functions do
3454 * not check if the processor is online before following the pageset pointer.
3455 * Other parts of the kernel may not check if the zone is available.
3457 static void setup_pageset(struct per_cpu_pageset
*p
, unsigned long batch
);
3458 static DEFINE_PER_CPU(struct per_cpu_pageset
, boot_pageset
);
3459 static void setup_zone_pageset(struct zone
*zone
);
3462 * Global mutex to protect against size modification of zonelists
3463 * as well as to serialize pageset setup for the new populated zone.
3465 DEFINE_MUTEX(zonelists_mutex
);
3467 /* return values int ....just for stop_machine() */
3468 static int __build_all_zonelists(void *data
)
3472 pg_data_t
*self
= data
;
3475 memset(node_load
, 0, sizeof(node_load
));
3478 if (self
&& !node_online(self
->node_id
)) {
3479 build_zonelists(self
);
3480 build_zonelist_cache(self
);
3483 for_each_online_node(nid
) {
3484 pg_data_t
*pgdat
= NODE_DATA(nid
);
3486 build_zonelists(pgdat
);
3487 build_zonelist_cache(pgdat
);
3491 * Initialize the boot_pagesets that are going to be used
3492 * for bootstrapping processors. The real pagesets for
3493 * each zone will be allocated later when the per cpu
3494 * allocator is available.
3496 * boot_pagesets are used also for bootstrapping offline
3497 * cpus if the system is already booted because the pagesets
3498 * are needed to initialize allocators on a specific cpu too.
3499 * F.e. the percpu allocator needs the page allocator which
3500 * needs the percpu allocator in order to allocate its pagesets
3501 * (a chicken-egg dilemma).
3503 for_each_possible_cpu(cpu
) {
3504 setup_pageset(&per_cpu(boot_pageset
, cpu
), 0);
3506 #ifdef CONFIG_HAVE_MEMORYLESS_NODES
3508 * We now know the "local memory node" for each node--
3509 * i.e., the node of the first zone in the generic zonelist.
3510 * Set up numa_mem percpu variable for on-line cpus. During
3511 * boot, only the boot cpu should be on-line; we'll init the
3512 * secondary cpus' numa_mem as they come on-line. During
3513 * node/memory hotplug, we'll fixup all on-line cpus.
3515 if (cpu_online(cpu
))
3516 set_cpu_numa_mem(cpu
, local_memory_node(cpu_to_node(cpu
)));
3524 * Called with zonelists_mutex held always
3525 * unless system_state == SYSTEM_BOOTING.
3527 void __ref
build_all_zonelists(pg_data_t
*pgdat
, struct zone
*zone
)
3529 set_zonelist_order();
3531 if (system_state
== SYSTEM_BOOTING
) {
3532 __build_all_zonelists(NULL
);
3533 mminit_verify_zonelist();
3534 cpuset_init_current_mems_allowed();
3536 /* we have to stop all cpus to guarantee there is no user
3538 #ifdef CONFIG_MEMORY_HOTPLUG
3540 setup_zone_pageset(zone
);
3542 stop_machine(__build_all_zonelists
, pgdat
, NULL
);
3543 /* cpuset refresh routine should be here */
3545 vm_total_pages
= nr_free_pagecache_pages();
3547 * Disable grouping by mobility if the number of pages in the
3548 * system is too low to allow the mechanism to work. It would be
3549 * more accurate, but expensive to check per-zone. This check is
3550 * made on memory-hotadd so a system can start with mobility
3551 * disabled and enable it later
3553 if (vm_total_pages
< (pageblock_nr_pages
* MIGRATE_TYPES
))
3554 page_group_by_mobility_disabled
= 1;
3556 page_group_by_mobility_disabled
= 0;
3558 printk("Built %i zonelists in %s order, mobility grouping %s. "
3559 "Total pages: %ld\n",
3561 zonelist_order_name
[current_zonelist_order
],
3562 page_group_by_mobility_disabled
? "off" : "on",
3565 printk("Policy zone: %s\n", zone_names
[policy_zone
]);
3570 * Helper functions to size the waitqueue hash table.
3571 * Essentially these want to choose hash table sizes sufficiently
3572 * large so that collisions trying to wait on pages are rare.
3573 * But in fact, the number of active page waitqueues on typical
3574 * systems is ridiculously low, less than 200. So this is even
3575 * conservative, even though it seems large.
3577 * The constant PAGES_PER_WAITQUEUE specifies the ratio of pages to
3578 * waitqueues, i.e. the size of the waitq table given the number of pages.
3580 #define PAGES_PER_WAITQUEUE 256
3582 #ifndef CONFIG_MEMORY_HOTPLUG
3583 static inline unsigned long wait_table_hash_nr_entries(unsigned long pages
)
3585 unsigned long size
= 1;
3587 pages
/= PAGES_PER_WAITQUEUE
;
3589 while (size
< pages
)
3593 * Once we have dozens or even hundreds of threads sleeping
3594 * on IO we've got bigger problems than wait queue collision.
3595 * Limit the size of the wait table to a reasonable size.
3597 size
= min(size
, 4096UL);
3599 return max(size
, 4UL);
3603 * A zone's size might be changed by hot-add, so it is not possible to determine
3604 * a suitable size for its wait_table. So we use the maximum size now.
3606 * The max wait table size = 4096 x sizeof(wait_queue_head_t). ie:
3608 * i386 (preemption config) : 4096 x 16 = 64Kbyte.
3609 * ia64, x86-64 (no preemption): 4096 x 20 = 80Kbyte.
3610 * ia64, x86-64 (preemption) : 4096 x 24 = 96Kbyte.
3612 * The maximum entries are prepared when a zone's memory is (512K + 256) pages
3613 * or more by the traditional way. (See above). It equals:
3615 * i386, x86-64, powerpc(4K page size) : = ( 2G + 1M)byte.
3616 * ia64(16K page size) : = ( 8G + 4M)byte.
3617 * powerpc (64K page size) : = (32G +16M)byte.
3619 static inline unsigned long wait_table_hash_nr_entries(unsigned long pages
)
3626 * This is an integer logarithm so that shifts can be used later
3627 * to extract the more random high bits from the multiplicative
3628 * hash function before the remainder is taken.
3630 static inline unsigned long wait_table_bits(unsigned long size
)
3635 #define LONG_ALIGN(x) (((x)+(sizeof(long))-1)&~((sizeof(long))-1))
3638 * Check if a pageblock contains reserved pages
3640 static int pageblock_is_reserved(unsigned long start_pfn
, unsigned long end_pfn
)
3644 for (pfn
= start_pfn
; pfn
< end_pfn
; pfn
++) {
3645 if (!pfn_valid_within(pfn
) || PageReserved(pfn_to_page(pfn
)))
3652 * Mark a number of pageblocks as MIGRATE_RESERVE. The number
3653 * of blocks reserved is based on min_wmark_pages(zone). The memory within
3654 * the reserve will tend to store contiguous free pages. Setting min_free_kbytes
3655 * higher will lead to a bigger reserve which will get freed as contiguous
3656 * blocks as reclaim kicks in
3658 static void setup_zone_migrate_reserve(struct zone
*zone
)
3660 unsigned long start_pfn
, pfn
, end_pfn
, block_end_pfn
;
3662 unsigned long block_migratetype
;
3666 * Get the start pfn, end pfn and the number of blocks to reserve
3667 * We have to be careful to be aligned to pageblock_nr_pages to
3668 * make sure that we always check pfn_valid for the first page in
3671 start_pfn
= zone
->zone_start_pfn
;
3672 end_pfn
= start_pfn
+ zone
->spanned_pages
;
3673 start_pfn
= roundup(start_pfn
, pageblock_nr_pages
);
3674 reserve
= roundup(min_wmark_pages(zone
), pageblock_nr_pages
) >>
3678 * Reserve blocks are generally in place to help high-order atomic
3679 * allocations that are short-lived. A min_free_kbytes value that
3680 * would result in more than 2 reserve blocks for atomic allocations
3681 * is assumed to be in place to help anti-fragmentation for the
3682 * future allocation of hugepages at runtime.
3684 reserve
= min(2, reserve
);
3686 for (pfn
= start_pfn
; pfn
< end_pfn
; pfn
+= pageblock_nr_pages
) {
3687 if (!pfn_valid(pfn
))
3689 page
= pfn_to_page(pfn
);
3691 /* Watch out for overlapping nodes */
3692 if (page_to_nid(page
) != zone_to_nid(zone
))
3695 block_migratetype
= get_pageblock_migratetype(page
);
3697 /* Only test what is necessary when the reserves are not met */
3700 * Blocks with reserved pages will never free, skip
3703 block_end_pfn
= min(pfn
+ pageblock_nr_pages
, end_pfn
);
3704 if (pageblock_is_reserved(pfn
, block_end_pfn
))
3707 /* If this block is reserved, account for it */
3708 if (block_migratetype
== MIGRATE_RESERVE
) {
3713 /* Suitable for reserving if this block is movable */
3714 if (block_migratetype
== MIGRATE_MOVABLE
) {
3715 set_pageblock_migratetype(page
,
3717 move_freepages_block(zone
, page
,
3725 * If the reserve is met and this is a previous reserved block,
3728 if (block_migratetype
== MIGRATE_RESERVE
) {
3729 set_pageblock_migratetype(page
, MIGRATE_MOVABLE
);
3730 move_freepages_block(zone
, page
, MIGRATE_MOVABLE
);
3736 * Initially all pages are reserved - free ones are freed
3737 * up by free_all_bootmem() once the early boot process is
3738 * done. Non-atomic initialization, single-pass.
3740 void __meminit
memmap_init_zone(unsigned long size
, int nid
, unsigned long zone
,
3741 unsigned long start_pfn
, enum memmap_context context
)
3744 unsigned long end_pfn
= start_pfn
+ size
;
3748 if (highest_memmap_pfn
< end_pfn
- 1)
3749 highest_memmap_pfn
= end_pfn
- 1;
3751 z
= &NODE_DATA(nid
)->node_zones
[zone
];
3752 for (pfn
= start_pfn
; pfn
< end_pfn
; pfn
++) {
3754 * There can be holes in boot-time mem_map[]s
3755 * handed to this function. They do not
3756 * exist on hotplugged memory.
3758 if (context
== MEMMAP_EARLY
) {
3759 if (!early_pfn_valid(pfn
))
3761 if (!early_pfn_in_nid(pfn
, nid
))
3764 page
= pfn_to_page(pfn
);
3765 set_page_links(page
, zone
, nid
, pfn
);
3766 mminit_verify_page_links(page
, zone
, nid
, pfn
);
3767 init_page_count(page
);
3768 reset_page_mapcount(page
);
3769 SetPageReserved(page
);
3771 * Mark the block movable so that blocks are reserved for
3772 * movable at startup. This will force kernel allocations
3773 * to reserve their blocks rather than leaking throughout
3774 * the address space during boot when many long-lived
3775 * kernel allocations are made. Later some blocks near
3776 * the start are marked MIGRATE_RESERVE by
3777 * setup_zone_migrate_reserve()
3779 * bitmap is created for zone's valid pfn range. but memmap
3780 * can be created for invalid pages (for alignment)
3781 * check here not to call set_pageblock_migratetype() against
3784 if ((z
->zone_start_pfn
<= pfn
)
3785 && (pfn
< z
->zone_start_pfn
+ z
->spanned_pages
)
3786 && !(pfn
& (pageblock_nr_pages
- 1)))
3787 set_pageblock_migratetype(page
, MIGRATE_MOVABLE
);
3789 INIT_LIST_HEAD(&page
->lru
);
3790 #ifdef WANT_PAGE_VIRTUAL
3791 /* The shift won't overflow because ZONE_NORMAL is below 4G. */
3792 if (!is_highmem_idx(zone
))
3793 set_page_address(page
, __va(pfn
<< PAGE_SHIFT
));
3798 static void __meminit
zone_init_free_lists(struct zone
*zone
)
3801 for_each_migratetype_order(order
, t
) {
3802 INIT_LIST_HEAD(&zone
->free_area
[order
].free_list
[t
]);
3803 zone
->free_area
[order
].nr_free
= 0;
3807 #ifndef __HAVE_ARCH_MEMMAP_INIT
3808 #define memmap_init(size, nid, zone, start_pfn) \
3809 memmap_init_zone((size), (nid), (zone), (start_pfn), MEMMAP_EARLY)
3812 static int __meminit
zone_batchsize(struct zone
*zone
)
3818 * The per-cpu-pages pools are set to around 1000th of the
3819 * size of the zone. But no more than 1/2 of a meg.
3821 * OK, so we don't know how big the cache is. So guess.
3823 batch
= zone
->present_pages
/ 1024;
3824 if (batch
* PAGE_SIZE
> 512 * 1024)
3825 batch
= (512 * 1024) / PAGE_SIZE
;
3826 batch
/= 4; /* We effectively *= 4 below */
3831 * Clamp the batch to a 2^n - 1 value. Having a power
3832 * of 2 value was found to be more likely to have
3833 * suboptimal cache aliasing properties in some cases.
3835 * For example if 2 tasks are alternately allocating
3836 * batches of pages, one task can end up with a lot
3837 * of pages of one half of the possible page colors
3838 * and the other with pages of the other colors.
3840 batch
= rounddown_pow_of_two(batch
+ batch
/2) - 1;
3845 /* The deferral and batching of frees should be suppressed under NOMMU
3848 * The problem is that NOMMU needs to be able to allocate large chunks
3849 * of contiguous memory as there's no hardware page translation to
3850 * assemble apparent contiguous memory from discontiguous pages.
3852 * Queueing large contiguous runs of pages for batching, however,
3853 * causes the pages to actually be freed in smaller chunks. As there
3854 * can be a significant delay between the individual batches being
3855 * recycled, this leads to the once large chunks of space being
3856 * fragmented and becoming unavailable for high-order allocations.
3862 static void setup_pageset(struct per_cpu_pageset
*p
, unsigned long batch
)
3864 struct per_cpu_pages
*pcp
;
3867 memset(p
, 0, sizeof(*p
));
3871 pcp
->high
= 6 * batch
;
3872 pcp
->batch
= max(1UL, 1 * batch
);
3873 for (migratetype
= 0; migratetype
< MIGRATE_PCPTYPES
; migratetype
++)
3874 INIT_LIST_HEAD(&pcp
->lists
[migratetype
]);
3878 * setup_pagelist_highmark() sets the high water mark for hot per_cpu_pagelist
3879 * to the value high for the pageset p.
3882 static void setup_pagelist_highmark(struct per_cpu_pageset
*p
,
3885 struct per_cpu_pages
*pcp
;
3889 pcp
->batch
= max(1UL, high
/4);
3890 if ((high
/4) > (PAGE_SHIFT
* 8))
3891 pcp
->batch
= PAGE_SHIFT
* 8;
3894 static void __meminit
setup_zone_pageset(struct zone
*zone
)
3898 zone
->pageset
= alloc_percpu(struct per_cpu_pageset
);
3900 for_each_possible_cpu(cpu
) {
3901 struct per_cpu_pageset
*pcp
= per_cpu_ptr(zone
->pageset
, cpu
);
3903 setup_pageset(pcp
, zone_batchsize(zone
));
3905 if (percpu_pagelist_fraction
)
3906 setup_pagelist_highmark(pcp
,
3907 (zone
->present_pages
/
3908 percpu_pagelist_fraction
));
3913 * Allocate per cpu pagesets and initialize them.
3914 * Before this call only boot pagesets were available.
3916 void __init
setup_per_cpu_pageset(void)
3920 for_each_populated_zone(zone
)
3921 setup_zone_pageset(zone
);
3924 static noinline __init_refok
3925 int zone_wait_table_init(struct zone
*zone
, unsigned long zone_size_pages
)
3928 struct pglist_data
*pgdat
= zone
->zone_pgdat
;
3932 * The per-page waitqueue mechanism uses hashed waitqueues
3935 zone
->wait_table_hash_nr_entries
=
3936 wait_table_hash_nr_entries(zone_size_pages
);
3937 zone
->wait_table_bits
=
3938 wait_table_bits(zone
->wait_table_hash_nr_entries
);
3939 alloc_size
= zone
->wait_table_hash_nr_entries
3940 * sizeof(wait_queue_head_t
);
3942 if (!slab_is_available()) {
3943 zone
->wait_table
= (wait_queue_head_t
*)
3944 alloc_bootmem_node_nopanic(pgdat
, alloc_size
);
3947 * This case means that a zone whose size was 0 gets new memory
3948 * via memory hot-add.
3949 * But it may be the case that a new node was hot-added. In
3950 * this case vmalloc() will not be able to use this new node's
3951 * memory - this wait_table must be initialized to use this new
3952 * node itself as well.
3953 * To use this new node's memory, further consideration will be
3956 zone
->wait_table
= vmalloc(alloc_size
);
3958 if (!zone
->wait_table
)
3961 for(i
= 0; i
< zone
->wait_table_hash_nr_entries
; ++i
)
3962 init_waitqueue_head(zone
->wait_table
+ i
);
3967 static __meminit
void zone_pcp_init(struct zone
*zone
)
3970 * per cpu subsystem is not up at this point. The following code
3971 * relies on the ability of the linker to provide the
3972 * offset of a (static) per cpu variable into the per cpu area.
3974 zone
->pageset
= &boot_pageset
;
3976 if (zone
->present_pages
)
3977 printk(KERN_DEBUG
" %s zone: %lu pages, LIFO batch:%u\n",
3978 zone
->name
, zone
->present_pages
,
3979 zone_batchsize(zone
));
3982 int __meminit
init_currently_empty_zone(struct zone
*zone
,
3983 unsigned long zone_start_pfn
,
3985 enum memmap_context context
)
3987 struct pglist_data
*pgdat
= zone
->zone_pgdat
;
3989 ret
= zone_wait_table_init(zone
, size
);
3992 pgdat
->nr_zones
= zone_idx(zone
) + 1;
3994 zone
->zone_start_pfn
= zone_start_pfn
;
3996 mminit_dprintk(MMINIT_TRACE
, "memmap_init",
3997 "Initialising map node %d zone %lu pfns %lu -> %lu\n",
3999 (unsigned long)zone_idx(zone
),
4000 zone_start_pfn
, (zone_start_pfn
+ size
));
4002 zone_init_free_lists(zone
);
4007 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
4008 #ifndef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
4010 * Required by SPARSEMEM. Given a PFN, return what node the PFN is on.
4011 * Architectures may implement their own version but if add_active_range()
4012 * was used and there are no special requirements, this is a convenient
4015 int __meminit
__early_pfn_to_nid(unsigned long pfn
)
4017 unsigned long start_pfn
, end_pfn
;
4020 for_each_mem_pfn_range(i
, MAX_NUMNODES
, &start_pfn
, &end_pfn
, &nid
)
4021 if (start_pfn
<= pfn
&& pfn
< end_pfn
)
4023 /* This is a memory hole */
4026 #endif /* CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID */
4028 int __meminit
early_pfn_to_nid(unsigned long pfn
)
4032 nid
= __early_pfn_to_nid(pfn
);
4035 /* just returns 0 */
4039 #ifdef CONFIG_NODES_SPAN_OTHER_NODES
4040 bool __meminit
early_pfn_in_nid(unsigned long pfn
, int node
)
4044 nid
= __early_pfn_to_nid(pfn
);
4045 if (nid
>= 0 && nid
!= node
)
4052 * free_bootmem_with_active_regions - Call free_bootmem_node for each active range
4053 * @nid: The node to free memory on. If MAX_NUMNODES, all nodes are freed.
4054 * @max_low_pfn: The highest PFN that will be passed to free_bootmem_node
4056 * If an architecture guarantees that all ranges registered with
4057 * add_active_ranges() contain no holes and may be freed, this
4058 * this function may be used instead of calling free_bootmem() manually.
4060 void __init
free_bootmem_with_active_regions(int nid
, unsigned long max_low_pfn
)
4062 unsigned long start_pfn
, end_pfn
;
4065 for_each_mem_pfn_range(i
, nid
, &start_pfn
, &end_pfn
, &this_nid
) {
4066 start_pfn
= min(start_pfn
, max_low_pfn
);
4067 end_pfn
= min(end_pfn
, max_low_pfn
);
4069 if (start_pfn
< end_pfn
)
4070 free_bootmem_node(NODE_DATA(this_nid
),
4071 PFN_PHYS(start_pfn
),
4072 (end_pfn
- start_pfn
) << PAGE_SHIFT
);
4077 * sparse_memory_present_with_active_regions - Call memory_present for each active range
4078 * @nid: The node to call memory_present for. If MAX_NUMNODES, all nodes will be used.
4080 * If an architecture guarantees that all ranges registered with
4081 * add_active_ranges() contain no holes and may be freed, this
4082 * function may be used instead of calling memory_present() manually.
4084 void __init
sparse_memory_present_with_active_regions(int nid
)
4086 unsigned long start_pfn
, end_pfn
;
4089 for_each_mem_pfn_range(i
, nid
, &start_pfn
, &end_pfn
, &this_nid
)
4090 memory_present(this_nid
, start_pfn
, end_pfn
);
4094 * get_pfn_range_for_nid - Return the start and end page frames for a node
4095 * @nid: The nid to return the range for. If MAX_NUMNODES, the min and max PFN are returned.
4096 * @start_pfn: Passed by reference. On return, it will have the node start_pfn.
4097 * @end_pfn: Passed by reference. On return, it will have the node end_pfn.
4099 * It returns the start and end page frame of a node based on information
4100 * provided by an arch calling add_active_range(). If called for a node
4101 * with no available memory, a warning is printed and the start and end
4104 void __meminit
get_pfn_range_for_nid(unsigned int nid
,
4105 unsigned long *start_pfn
, unsigned long *end_pfn
)
4107 unsigned long this_start_pfn
, this_end_pfn
;
4113 for_each_mem_pfn_range(i
, nid
, &this_start_pfn
, &this_end_pfn
, NULL
) {
4114 *start_pfn
= min(*start_pfn
, this_start_pfn
);
4115 *end_pfn
= max(*end_pfn
, this_end_pfn
);
4118 if (*start_pfn
== -1UL)
4123 * This finds a zone that can be used for ZONE_MOVABLE pages. The
4124 * assumption is made that zones within a node are ordered in monotonic
4125 * increasing memory addresses so that the "highest" populated zone is used
4127 static void __init
find_usable_zone_for_movable(void)
4130 for (zone_index
= MAX_NR_ZONES
- 1; zone_index
>= 0; zone_index
--) {
4131 if (zone_index
== ZONE_MOVABLE
)
4134 if (arch_zone_highest_possible_pfn
[zone_index
] >
4135 arch_zone_lowest_possible_pfn
[zone_index
])
4139 VM_BUG_ON(zone_index
== -1);
4140 movable_zone
= zone_index
;
4144 * The zone ranges provided by the architecture do not include ZONE_MOVABLE
4145 * because it is sized independent of architecture. Unlike the other zones,
4146 * the starting point for ZONE_MOVABLE is not fixed. It may be different
4147 * in each node depending on the size of each node and how evenly kernelcore
4148 * is distributed. This helper function adjusts the zone ranges
4149 * provided by the architecture for a given node by using the end of the
4150 * highest usable zone for ZONE_MOVABLE. This preserves the assumption that
4151 * zones within a node are in order of monotonic increases memory addresses
4153 static void __meminit
adjust_zone_range_for_zone_movable(int nid
,
4154 unsigned long zone_type
,
4155 unsigned long node_start_pfn
,
4156 unsigned long node_end_pfn
,
4157 unsigned long *zone_start_pfn
,
4158 unsigned long *zone_end_pfn
)
4160 /* Only adjust if ZONE_MOVABLE is on this node */
4161 if (zone_movable_pfn
[nid
]) {
4162 /* Size ZONE_MOVABLE */
4163 if (zone_type
== ZONE_MOVABLE
) {
4164 *zone_start_pfn
= zone_movable_pfn
[nid
];
4165 *zone_end_pfn
= min(node_end_pfn
,
4166 arch_zone_highest_possible_pfn
[movable_zone
]);
4168 /* Adjust for ZONE_MOVABLE starting within this range */
4169 } else if (*zone_start_pfn
< zone_movable_pfn
[nid
] &&
4170 *zone_end_pfn
> zone_movable_pfn
[nid
]) {
4171 *zone_end_pfn
= zone_movable_pfn
[nid
];
4173 /* Check if this whole range is within ZONE_MOVABLE */
4174 } else if (*zone_start_pfn
>= zone_movable_pfn
[nid
])
4175 *zone_start_pfn
= *zone_end_pfn
;
4180 * Return the number of pages a zone spans in a node, including holes
4181 * present_pages = zone_spanned_pages_in_node() - zone_absent_pages_in_node()
4183 static unsigned long __meminit
zone_spanned_pages_in_node(int nid
,
4184 unsigned long zone_type
,
4185 unsigned long *ignored
)
4187 unsigned long node_start_pfn
, node_end_pfn
;
4188 unsigned long zone_start_pfn
, zone_end_pfn
;
4190 /* Get the start and end of the node and zone */
4191 get_pfn_range_for_nid(nid
, &node_start_pfn
, &node_end_pfn
);
4192 zone_start_pfn
= arch_zone_lowest_possible_pfn
[zone_type
];
4193 zone_end_pfn
= arch_zone_highest_possible_pfn
[zone_type
];
4194 adjust_zone_range_for_zone_movable(nid
, zone_type
,
4195 node_start_pfn
, node_end_pfn
,
4196 &zone_start_pfn
, &zone_end_pfn
);
4198 /* Check that this node has pages within the zone's required range */
4199 if (zone_end_pfn
< node_start_pfn
|| zone_start_pfn
> node_end_pfn
)
4202 /* Move the zone boundaries inside the node if necessary */
4203 zone_end_pfn
= min(zone_end_pfn
, node_end_pfn
);
4204 zone_start_pfn
= max(zone_start_pfn
, node_start_pfn
);
4206 /* Return the spanned pages */
4207 return zone_end_pfn
- zone_start_pfn
;
4211 * Return the number of holes in a range on a node. If nid is MAX_NUMNODES,
4212 * then all holes in the requested range will be accounted for.
4214 unsigned long __meminit
__absent_pages_in_range(int nid
,
4215 unsigned long range_start_pfn
,
4216 unsigned long range_end_pfn
)
4218 unsigned long nr_absent
= range_end_pfn
- range_start_pfn
;
4219 unsigned long start_pfn
, end_pfn
;
4222 for_each_mem_pfn_range(i
, nid
, &start_pfn
, &end_pfn
, NULL
) {
4223 start_pfn
= clamp(start_pfn
, range_start_pfn
, range_end_pfn
);
4224 end_pfn
= clamp(end_pfn
, range_start_pfn
, range_end_pfn
);
4225 nr_absent
-= end_pfn
- start_pfn
;
4231 * absent_pages_in_range - Return number of page frames in holes within a range
4232 * @start_pfn: The start PFN to start searching for holes
4233 * @end_pfn: The end PFN to stop searching for holes
4235 * It returns the number of pages frames in memory holes within a range.
4237 unsigned long __init
absent_pages_in_range(unsigned long start_pfn
,
4238 unsigned long end_pfn
)
4240 return __absent_pages_in_range(MAX_NUMNODES
, start_pfn
, end_pfn
);
4243 /* Return the number of page frames in holes in a zone on a node */
4244 static unsigned long __meminit
zone_absent_pages_in_node(int nid
,
4245 unsigned long zone_type
,
4246 unsigned long *ignored
)
4248 unsigned long zone_low
= arch_zone_lowest_possible_pfn
[zone_type
];
4249 unsigned long zone_high
= arch_zone_highest_possible_pfn
[zone_type
];
4250 unsigned long node_start_pfn
, node_end_pfn
;
4251 unsigned long zone_start_pfn
, zone_end_pfn
;
4253 get_pfn_range_for_nid(nid
, &node_start_pfn
, &node_end_pfn
);
4254 zone_start_pfn
= clamp(node_start_pfn
, zone_low
, zone_high
);
4255 zone_end_pfn
= clamp(node_end_pfn
, zone_low
, zone_high
);
4257 adjust_zone_range_for_zone_movable(nid
, zone_type
,
4258 node_start_pfn
, node_end_pfn
,
4259 &zone_start_pfn
, &zone_end_pfn
);
4260 return __absent_pages_in_range(nid
, zone_start_pfn
, zone_end_pfn
);
4263 #else /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
4264 static inline unsigned long __meminit
zone_spanned_pages_in_node(int nid
,
4265 unsigned long zone_type
,
4266 unsigned long *zones_size
)
4268 return zones_size
[zone_type
];
4271 static inline unsigned long __meminit
zone_absent_pages_in_node(int nid
,
4272 unsigned long zone_type
,
4273 unsigned long *zholes_size
)
4278 return zholes_size
[zone_type
];
4281 #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
4283 static void __meminit
calculate_node_totalpages(struct pglist_data
*pgdat
,
4284 unsigned long *zones_size
, unsigned long *zholes_size
)
4286 unsigned long realtotalpages
, totalpages
= 0;
4289 for (i
= 0; i
< MAX_NR_ZONES
; i
++)
4290 totalpages
+= zone_spanned_pages_in_node(pgdat
->node_id
, i
,
4292 pgdat
->node_spanned_pages
= totalpages
;
4294 realtotalpages
= totalpages
;
4295 for (i
= 0; i
< MAX_NR_ZONES
; i
++)
4297 zone_absent_pages_in_node(pgdat
->node_id
, i
,
4299 pgdat
->node_present_pages
= realtotalpages
;
4300 printk(KERN_DEBUG
"On node %d totalpages: %lu\n", pgdat
->node_id
,
4304 #ifndef CONFIG_SPARSEMEM
4306 * Calculate the size of the zone->blockflags rounded to an unsigned long
4307 * Start by making sure zonesize is a multiple of pageblock_order by rounding
4308 * up. Then use 1 NR_PAGEBLOCK_BITS worth of bits per pageblock, finally
4309 * round what is now in bits to nearest long in bits, then return it in
4312 static unsigned long __init
usemap_size(unsigned long zonesize
)
4314 unsigned long usemapsize
;
4316 usemapsize
= roundup(zonesize
, pageblock_nr_pages
);
4317 usemapsize
= usemapsize
>> pageblock_order
;
4318 usemapsize
*= NR_PAGEBLOCK_BITS
;
4319 usemapsize
= roundup(usemapsize
, 8 * sizeof(unsigned long));
4321 return usemapsize
/ 8;
4324 static void __init
setup_usemap(struct pglist_data
*pgdat
,
4325 struct zone
*zone
, unsigned long zonesize
)
4327 unsigned long usemapsize
= usemap_size(zonesize
);
4328 zone
->pageblock_flags
= NULL
;
4330 zone
->pageblock_flags
= alloc_bootmem_node_nopanic(pgdat
,
4334 static inline void setup_usemap(struct pglist_data
*pgdat
,
4335 struct zone
*zone
, unsigned long zonesize
) {}
4336 #endif /* CONFIG_SPARSEMEM */
4338 #ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
4340 /* Initialise the number of pages represented by NR_PAGEBLOCK_BITS */
4341 void __init
set_pageblock_order(void)
4345 /* Check that pageblock_nr_pages has not already been setup */
4346 if (pageblock_order
)
4349 if (HPAGE_SHIFT
> PAGE_SHIFT
)
4350 order
= HUGETLB_PAGE_ORDER
;
4352 order
= MAX_ORDER
- 1;
4355 * Assume the largest contiguous order of interest is a huge page.
4356 * This value may be variable depending on boot parameters on IA64 and
4359 pageblock_order
= order
;
4361 #else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
4364 * When CONFIG_HUGETLB_PAGE_SIZE_VARIABLE is not set, set_pageblock_order()
4365 * is unused as pageblock_order is set at compile-time. See
4366 * include/linux/pageblock-flags.h for the values of pageblock_order based on
4369 void __init
set_pageblock_order(void)
4373 #endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
4376 * Set up the zone data structures:
4377 * - mark all pages reserved
4378 * - mark all memory queues empty
4379 * - clear the memory bitmaps
4381 * NOTE: pgdat should get zeroed by caller.
4383 static void __paginginit
free_area_init_core(struct pglist_data
*pgdat
,
4384 unsigned long *zones_size
, unsigned long *zholes_size
)
4387 int nid
= pgdat
->node_id
;
4388 unsigned long zone_start_pfn
= pgdat
->node_start_pfn
;
4391 pgdat_resize_init(pgdat
);
4392 init_waitqueue_head(&pgdat
->kswapd_wait
);
4393 init_waitqueue_head(&pgdat
->pfmemalloc_wait
);
4394 pgdat_page_cgroup_init(pgdat
);
4396 for (j
= 0; j
< MAX_NR_ZONES
; j
++) {
4397 struct zone
*zone
= pgdat
->node_zones
+ j
;
4398 unsigned long size
, realsize
, memmap_pages
;
4400 size
= zone_spanned_pages_in_node(nid
, j
, zones_size
);
4401 realsize
= size
- zone_absent_pages_in_node(nid
, j
,
4405 * Adjust realsize so that it accounts for how much memory
4406 * is used by this zone for memmap. This affects the watermark
4407 * and per-cpu initialisations
4410 PAGE_ALIGN(size
* sizeof(struct page
)) >> PAGE_SHIFT
;
4411 if (realsize
>= memmap_pages
) {
4412 realsize
-= memmap_pages
;
4415 " %s zone: %lu pages used for memmap\n",
4416 zone_names
[j
], memmap_pages
);
4419 " %s zone: %lu pages exceeds realsize %lu\n",
4420 zone_names
[j
], memmap_pages
, realsize
);
4422 /* Account for reserved pages */
4423 if (j
== 0 && realsize
> dma_reserve
) {
4424 realsize
-= dma_reserve
;
4425 printk(KERN_DEBUG
" %s zone: %lu pages reserved\n",
4426 zone_names
[0], dma_reserve
);
4429 if (!is_highmem_idx(j
))
4430 nr_kernel_pages
+= realsize
;
4431 nr_all_pages
+= realsize
;
4433 zone
->spanned_pages
= size
;
4434 zone
->present_pages
= realsize
;
4435 #if defined CONFIG_COMPACTION || defined CONFIG_CMA
4436 zone
->compact_cached_free_pfn
= zone
->zone_start_pfn
+
4437 zone
->spanned_pages
;
4438 zone
->compact_cached_free_pfn
&= ~(pageblock_nr_pages
-1);
4442 zone
->min_unmapped_pages
= (realsize
*sysctl_min_unmapped_ratio
)
4444 zone
->min_slab_pages
= (realsize
* sysctl_min_slab_ratio
) / 100;
4446 zone
->name
= zone_names
[j
];
4447 spin_lock_init(&zone
->lock
);
4448 spin_lock_init(&zone
->lru_lock
);
4449 zone_seqlock_init(zone
);
4450 zone
->zone_pgdat
= pgdat
;
4452 zone_pcp_init(zone
);
4453 lruvec_init(&zone
->lruvec
, zone
);
4457 set_pageblock_order();
4458 setup_usemap(pgdat
, zone
, size
);
4459 ret
= init_currently_empty_zone(zone
, zone_start_pfn
,
4460 size
, MEMMAP_EARLY
);
4462 memmap_init(size
, nid
, j
, zone_start_pfn
);
4463 zone_start_pfn
+= size
;
4467 static void __init_refok
alloc_node_mem_map(struct pglist_data
*pgdat
)
4469 /* Skip empty nodes */
4470 if (!pgdat
->node_spanned_pages
)
4473 #ifdef CONFIG_FLAT_NODE_MEM_MAP
4474 /* ia64 gets its own node_mem_map, before this, without bootmem */
4475 if (!pgdat
->node_mem_map
) {
4476 unsigned long size
, start
, end
;
4480 * The zone's endpoints aren't required to be MAX_ORDER
4481 * aligned but the node_mem_map endpoints must be in order
4482 * for the buddy allocator to function correctly.
4484 start
= pgdat
->node_start_pfn
& ~(MAX_ORDER_NR_PAGES
- 1);
4485 end
= pgdat
->node_start_pfn
+ pgdat
->node_spanned_pages
;
4486 end
= ALIGN(end
, MAX_ORDER_NR_PAGES
);
4487 size
= (end
- start
) * sizeof(struct page
);
4488 map
= alloc_remap(pgdat
->node_id
, size
);
4490 map
= alloc_bootmem_node_nopanic(pgdat
, size
);
4491 pgdat
->node_mem_map
= map
+ (pgdat
->node_start_pfn
- start
);
4493 #ifndef CONFIG_NEED_MULTIPLE_NODES
4495 * With no DISCONTIG, the global mem_map is just set as node 0's
4497 if (pgdat
== NODE_DATA(0)) {
4498 mem_map
= NODE_DATA(0)->node_mem_map
;
4499 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
4500 if (page_to_pfn(mem_map
) != pgdat
->node_start_pfn
)
4501 mem_map
-= (pgdat
->node_start_pfn
- ARCH_PFN_OFFSET
);
4502 #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
4505 #endif /* CONFIG_FLAT_NODE_MEM_MAP */
4508 void __paginginit
free_area_init_node(int nid
, unsigned long *zones_size
,
4509 unsigned long node_start_pfn
, unsigned long *zholes_size
)
4511 pg_data_t
*pgdat
= NODE_DATA(nid
);
4513 /* pg_data_t should be reset to zero when it's allocated */
4514 WARN_ON(pgdat
->nr_zones
|| pgdat
->node_start_pfn
|| pgdat
->classzone_idx
);
4516 pgdat
->node_id
= nid
;
4517 pgdat
->node_start_pfn
= node_start_pfn
;
4518 calculate_node_totalpages(pgdat
, zones_size
, zholes_size
);
4520 alloc_node_mem_map(pgdat
);
4521 #ifdef CONFIG_FLAT_NODE_MEM_MAP
4522 printk(KERN_DEBUG
"free_area_init_node: node %d, pgdat %08lx, node_mem_map %08lx\n",
4523 nid
, (unsigned long)pgdat
,
4524 (unsigned long)pgdat
->node_mem_map
);
4527 free_area_init_core(pgdat
, zones_size
, zholes_size
);
4530 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
4532 #if MAX_NUMNODES > 1
4534 * Figure out the number of possible node ids.
4536 static void __init
setup_nr_node_ids(void)
4539 unsigned int highest
= 0;
4541 for_each_node_mask(node
, node_possible_map
)
4543 nr_node_ids
= highest
+ 1;
4546 static inline void setup_nr_node_ids(void)
4552 * node_map_pfn_alignment - determine the maximum internode alignment
4554 * This function should be called after node map is populated and sorted.
4555 * It calculates the maximum power of two alignment which can distinguish
4558 * For example, if all nodes are 1GiB and aligned to 1GiB, the return value
4559 * would indicate 1GiB alignment with (1 << (30 - PAGE_SHIFT)). If the
4560 * nodes are shifted by 256MiB, 256MiB. Note that if only the last node is
4561 * shifted, 1GiB is enough and this function will indicate so.
4563 * This is used to test whether pfn -> nid mapping of the chosen memory
4564 * model has fine enough granularity to avoid incorrect mapping for the
4565 * populated node map.
4567 * Returns the determined alignment in pfn's. 0 if there is no alignment
4568 * requirement (single node).
4570 unsigned long __init
node_map_pfn_alignment(void)
4572 unsigned long accl_mask
= 0, last_end
= 0;
4573 unsigned long start
, end
, mask
;
4577 for_each_mem_pfn_range(i
, MAX_NUMNODES
, &start
, &end
, &nid
) {
4578 if (!start
|| last_nid
< 0 || last_nid
== nid
) {
4585 * Start with a mask granular enough to pin-point to the
4586 * start pfn and tick off bits one-by-one until it becomes
4587 * too coarse to separate the current node from the last.
4589 mask
= ~((1 << __ffs(start
)) - 1);
4590 while (mask
&& last_end
<= (start
& (mask
<< 1)))
4593 /* accumulate all internode masks */
4597 /* convert mask to number of pages */
4598 return ~accl_mask
+ 1;
4601 /* Find the lowest pfn for a node */
4602 static unsigned long __init
find_min_pfn_for_node(int nid
)
4604 unsigned long min_pfn
= ULONG_MAX
;
4605 unsigned long start_pfn
;
4608 for_each_mem_pfn_range(i
, nid
, &start_pfn
, NULL
, NULL
)
4609 min_pfn
= min(min_pfn
, start_pfn
);
4611 if (min_pfn
== ULONG_MAX
) {
4613 "Could not find start_pfn for node %d\n", nid
);
4621 * find_min_pfn_with_active_regions - Find the minimum PFN registered
4623 * It returns the minimum PFN based on information provided via
4624 * add_active_range().
4626 unsigned long __init
find_min_pfn_with_active_regions(void)
4628 return find_min_pfn_for_node(MAX_NUMNODES
);
4632 * early_calculate_totalpages()
4633 * Sum pages in active regions for movable zone.
4634 * Populate N_HIGH_MEMORY for calculating usable_nodes.
4636 static unsigned long __init
early_calculate_totalpages(void)
4638 unsigned long totalpages
= 0;
4639 unsigned long start_pfn
, end_pfn
;
4642 for_each_mem_pfn_range(i
, MAX_NUMNODES
, &start_pfn
, &end_pfn
, &nid
) {
4643 unsigned long pages
= end_pfn
- start_pfn
;
4645 totalpages
+= pages
;
4647 node_set_state(nid
, N_HIGH_MEMORY
);
4653 * Find the PFN the Movable zone begins in each node. Kernel memory
4654 * is spread evenly between nodes as long as the nodes have enough
4655 * memory. When they don't, some nodes will have more kernelcore than
4658 static void __init
find_zone_movable_pfns_for_nodes(void)
4661 unsigned long usable_startpfn
;
4662 unsigned long kernelcore_node
, kernelcore_remaining
;
4663 /* save the state before borrow the nodemask */
4664 nodemask_t saved_node_state
= node_states
[N_HIGH_MEMORY
];
4665 unsigned long totalpages
= early_calculate_totalpages();
4666 int usable_nodes
= nodes_weight(node_states
[N_HIGH_MEMORY
]);
4669 * If movablecore was specified, calculate what size of
4670 * kernelcore that corresponds so that memory usable for
4671 * any allocation type is evenly spread. If both kernelcore
4672 * and movablecore are specified, then the value of kernelcore
4673 * will be used for required_kernelcore if it's greater than
4674 * what movablecore would have allowed.
4676 if (required_movablecore
) {
4677 unsigned long corepages
;
4680 * Round-up so that ZONE_MOVABLE is at least as large as what
4681 * was requested by the user
4683 required_movablecore
=
4684 roundup(required_movablecore
, MAX_ORDER_NR_PAGES
);
4685 corepages
= totalpages
- required_movablecore
;
4687 required_kernelcore
= max(required_kernelcore
, corepages
);
4690 /* If kernelcore was not specified, there is no ZONE_MOVABLE */
4691 if (!required_kernelcore
)
4694 /* usable_startpfn is the lowest possible pfn ZONE_MOVABLE can be at */
4695 find_usable_zone_for_movable();
4696 usable_startpfn
= arch_zone_lowest_possible_pfn
[movable_zone
];
4699 /* Spread kernelcore memory as evenly as possible throughout nodes */
4700 kernelcore_node
= required_kernelcore
/ usable_nodes
;
4701 for_each_node_state(nid
, N_HIGH_MEMORY
) {
4702 unsigned long start_pfn
, end_pfn
;
4705 * Recalculate kernelcore_node if the division per node
4706 * now exceeds what is necessary to satisfy the requested
4707 * amount of memory for the kernel
4709 if (required_kernelcore
< kernelcore_node
)
4710 kernelcore_node
= required_kernelcore
/ usable_nodes
;
4713 * As the map is walked, we track how much memory is usable
4714 * by the kernel using kernelcore_remaining. When it is
4715 * 0, the rest of the node is usable by ZONE_MOVABLE
4717 kernelcore_remaining
= kernelcore_node
;
4719 /* Go through each range of PFNs within this node */
4720 for_each_mem_pfn_range(i
, nid
, &start_pfn
, &end_pfn
, NULL
) {
4721 unsigned long size_pages
;
4723 start_pfn
= max(start_pfn
, zone_movable_pfn
[nid
]);
4724 if (start_pfn
>= end_pfn
)
4727 /* Account for what is only usable for kernelcore */
4728 if (start_pfn
< usable_startpfn
) {
4729 unsigned long kernel_pages
;
4730 kernel_pages
= min(end_pfn
, usable_startpfn
)
4733 kernelcore_remaining
-= min(kernel_pages
,
4734 kernelcore_remaining
);
4735 required_kernelcore
-= min(kernel_pages
,
4736 required_kernelcore
);
4738 /* Continue if range is now fully accounted */
4739 if (end_pfn
<= usable_startpfn
) {
4742 * Push zone_movable_pfn to the end so
4743 * that if we have to rebalance
4744 * kernelcore across nodes, we will
4745 * not double account here
4747 zone_movable_pfn
[nid
] = end_pfn
;
4750 start_pfn
= usable_startpfn
;
4754 * The usable PFN range for ZONE_MOVABLE is from
4755 * start_pfn->end_pfn. Calculate size_pages as the
4756 * number of pages used as kernelcore
4758 size_pages
= end_pfn
- start_pfn
;
4759 if (size_pages
> kernelcore_remaining
)
4760 size_pages
= kernelcore_remaining
;
4761 zone_movable_pfn
[nid
] = start_pfn
+ size_pages
;
4764 * Some kernelcore has been met, update counts and
4765 * break if the kernelcore for this node has been
4768 required_kernelcore
-= min(required_kernelcore
,
4770 kernelcore_remaining
-= size_pages
;
4771 if (!kernelcore_remaining
)
4777 * If there is still required_kernelcore, we do another pass with one
4778 * less node in the count. This will push zone_movable_pfn[nid] further
4779 * along on the nodes that still have memory until kernelcore is
4783 if (usable_nodes
&& required_kernelcore
> usable_nodes
)
4786 /* Align start of ZONE_MOVABLE on all nids to MAX_ORDER_NR_PAGES */
4787 for (nid
= 0; nid
< MAX_NUMNODES
; nid
++)
4788 zone_movable_pfn
[nid
] =
4789 roundup(zone_movable_pfn
[nid
], MAX_ORDER_NR_PAGES
);
4792 /* restore the node_state */
4793 node_states
[N_HIGH_MEMORY
] = saved_node_state
;
4796 /* Any regular memory on that node ? */
4797 static void __init
check_for_regular_memory(pg_data_t
*pgdat
)
4799 #ifdef CONFIG_HIGHMEM
4800 enum zone_type zone_type
;
4802 for (zone_type
= 0; zone_type
<= ZONE_NORMAL
; zone_type
++) {
4803 struct zone
*zone
= &pgdat
->node_zones
[zone_type
];
4804 if (zone
->present_pages
) {
4805 node_set_state(zone_to_nid(zone
), N_NORMAL_MEMORY
);
4813 * free_area_init_nodes - Initialise all pg_data_t and zone data
4814 * @max_zone_pfn: an array of max PFNs for each zone
4816 * This will call free_area_init_node() for each active node in the system.
4817 * Using the page ranges provided by add_active_range(), the size of each
4818 * zone in each node and their holes is calculated. If the maximum PFN
4819 * between two adjacent zones match, it is assumed that the zone is empty.
4820 * For example, if arch_max_dma_pfn == arch_max_dma32_pfn, it is assumed
4821 * that arch_max_dma32_pfn has no pages. It is also assumed that a zone
4822 * starts where the previous one ended. For example, ZONE_DMA32 starts
4823 * at arch_max_dma_pfn.
4825 void __init
free_area_init_nodes(unsigned long *max_zone_pfn
)
4827 unsigned long start_pfn
, end_pfn
;
4830 /* Record where the zone boundaries are */
4831 memset(arch_zone_lowest_possible_pfn
, 0,
4832 sizeof(arch_zone_lowest_possible_pfn
));
4833 memset(arch_zone_highest_possible_pfn
, 0,
4834 sizeof(arch_zone_highest_possible_pfn
));
4835 arch_zone_lowest_possible_pfn
[0] = find_min_pfn_with_active_regions();
4836 arch_zone_highest_possible_pfn
[0] = max_zone_pfn
[0];
4837 for (i
= 1; i
< MAX_NR_ZONES
; i
++) {
4838 if (i
== ZONE_MOVABLE
)
4840 arch_zone_lowest_possible_pfn
[i
] =
4841 arch_zone_highest_possible_pfn
[i
-1];
4842 arch_zone_highest_possible_pfn
[i
] =
4843 max(max_zone_pfn
[i
], arch_zone_lowest_possible_pfn
[i
]);
4845 arch_zone_lowest_possible_pfn
[ZONE_MOVABLE
] = 0;
4846 arch_zone_highest_possible_pfn
[ZONE_MOVABLE
] = 0;
4848 /* Find the PFNs that ZONE_MOVABLE begins at in each node */
4849 memset(zone_movable_pfn
, 0, sizeof(zone_movable_pfn
));
4850 find_zone_movable_pfns_for_nodes();
4852 /* Print out the zone ranges */
4853 printk("Zone ranges:\n");
4854 for (i
= 0; i
< MAX_NR_ZONES
; i
++) {
4855 if (i
== ZONE_MOVABLE
)
4857 printk(KERN_CONT
" %-8s ", zone_names
[i
]);
4858 if (arch_zone_lowest_possible_pfn
[i
] ==
4859 arch_zone_highest_possible_pfn
[i
])
4860 printk(KERN_CONT
"empty\n");
4862 printk(KERN_CONT
"[mem %0#10lx-%0#10lx]\n",
4863 arch_zone_lowest_possible_pfn
[i
] << PAGE_SHIFT
,
4864 (arch_zone_highest_possible_pfn
[i
]
4865 << PAGE_SHIFT
) - 1);
4868 /* Print out the PFNs ZONE_MOVABLE begins at in each node */
4869 printk("Movable zone start for each node\n");
4870 for (i
= 0; i
< MAX_NUMNODES
; i
++) {
4871 if (zone_movable_pfn
[i
])
4872 printk(" Node %d: %#010lx\n", i
,
4873 zone_movable_pfn
[i
] << PAGE_SHIFT
);
4876 /* Print out the early_node_map[] */
4877 printk("Early memory node ranges\n");
4878 for_each_mem_pfn_range(i
, MAX_NUMNODES
, &start_pfn
, &end_pfn
, &nid
)
4879 printk(" node %3d: [mem %#010lx-%#010lx]\n", nid
,
4880 start_pfn
<< PAGE_SHIFT
, (end_pfn
<< PAGE_SHIFT
) - 1);
4882 /* Initialise every node */
4883 mminit_verify_pageflags_layout();
4884 setup_nr_node_ids();
4885 for_each_online_node(nid
) {
4886 pg_data_t
*pgdat
= NODE_DATA(nid
);
4887 free_area_init_node(nid
, NULL
,
4888 find_min_pfn_for_node(nid
), NULL
);
4890 /* Any memory on that node */
4891 if (pgdat
->node_present_pages
)
4892 node_set_state(nid
, N_HIGH_MEMORY
);
4893 check_for_regular_memory(pgdat
);
4897 static int __init
cmdline_parse_core(char *p
, unsigned long *core
)
4899 unsigned long long coremem
;
4903 coremem
= memparse(p
, &p
);
4904 *core
= coremem
>> PAGE_SHIFT
;
4906 /* Paranoid check that UL is enough for the coremem value */
4907 WARN_ON((coremem
>> PAGE_SHIFT
) > ULONG_MAX
);
4913 * kernelcore=size sets the amount of memory for use for allocations that
4914 * cannot be reclaimed or migrated.
4916 static int __init
cmdline_parse_kernelcore(char *p
)
4918 return cmdline_parse_core(p
, &required_kernelcore
);
4922 * movablecore=size sets the amount of memory for use for allocations that
4923 * can be reclaimed or migrated.
4925 static int __init
cmdline_parse_movablecore(char *p
)
4927 return cmdline_parse_core(p
, &required_movablecore
);
4930 early_param("kernelcore", cmdline_parse_kernelcore
);
4931 early_param("movablecore", cmdline_parse_movablecore
);
4933 #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
4936 * set_dma_reserve - set the specified number of pages reserved in the first zone
4937 * @new_dma_reserve: The number of pages to mark reserved
4939 * The per-cpu batchsize and zone watermarks are determined by present_pages.
4940 * In the DMA zone, a significant percentage may be consumed by kernel image
4941 * and other unfreeable allocations which can skew the watermarks badly. This
4942 * function may optionally be used to account for unfreeable pages in the
4943 * first zone (e.g., ZONE_DMA). The effect will be lower watermarks and
4944 * smaller per-cpu batchsize.
4946 void __init
set_dma_reserve(unsigned long new_dma_reserve
)
4948 dma_reserve
= new_dma_reserve
;
4951 void __init
free_area_init(unsigned long *zones_size
)
4953 free_area_init_node(0, zones_size
,
4954 __pa(PAGE_OFFSET
) >> PAGE_SHIFT
, NULL
);
4957 static int page_alloc_cpu_notify(struct notifier_block
*self
,
4958 unsigned long action
, void *hcpu
)
4960 int cpu
= (unsigned long)hcpu
;
4962 if (action
== CPU_DEAD
|| action
== CPU_DEAD_FROZEN
) {
4963 lru_add_drain_cpu(cpu
);
4967 * Spill the event counters of the dead processor
4968 * into the current processors event counters.
4969 * This artificially elevates the count of the current
4972 vm_events_fold_cpu(cpu
);
4975 * Zero the differential counters of the dead processor
4976 * so that the vm statistics are consistent.
4978 * This is only okay since the processor is dead and cannot
4979 * race with what we are doing.
4981 refresh_cpu_vm_stats(cpu
);
4986 void __init
page_alloc_init(void)
4988 hotcpu_notifier(page_alloc_cpu_notify
, 0);
4992 * calculate_totalreserve_pages - called when sysctl_lower_zone_reserve_ratio
4993 * or min_free_kbytes changes.
4995 static void calculate_totalreserve_pages(void)
4997 struct pglist_data
*pgdat
;
4998 unsigned long reserve_pages
= 0;
4999 enum zone_type i
, j
;
5001 for_each_online_pgdat(pgdat
) {
5002 for (i
= 0; i
< MAX_NR_ZONES
; i
++) {
5003 struct zone
*zone
= pgdat
->node_zones
+ i
;
5004 unsigned long max
= 0;
5006 /* Find valid and maximum lowmem_reserve in the zone */
5007 for (j
= i
; j
< MAX_NR_ZONES
; j
++) {
5008 if (zone
->lowmem_reserve
[j
] > max
)
5009 max
= zone
->lowmem_reserve
[j
];
5012 /* we treat the high watermark as reserved pages. */
5013 max
+= high_wmark_pages(zone
);
5015 if (max
> zone
->present_pages
)
5016 max
= zone
->present_pages
;
5017 reserve_pages
+= max
;
5019 * Lowmem reserves are not available to
5020 * GFP_HIGHUSER page cache allocations and
5021 * kswapd tries to balance zones to their high
5022 * watermark. As a result, neither should be
5023 * regarded as dirtyable memory, to prevent a
5024 * situation where reclaim has to clean pages
5025 * in order to balance the zones.
5027 zone
->dirty_balance_reserve
= max
;
5030 dirty_balance_reserve
= reserve_pages
;
5031 totalreserve_pages
= reserve_pages
;
5035 * setup_per_zone_lowmem_reserve - called whenever
5036 * sysctl_lower_zone_reserve_ratio changes. Ensures that each zone
5037 * has a correct pages reserved value, so an adequate number of
5038 * pages are left in the zone after a successful __alloc_pages().
5040 static void setup_per_zone_lowmem_reserve(void)
5042 struct pglist_data
*pgdat
;
5043 enum zone_type j
, idx
;
5045 for_each_online_pgdat(pgdat
) {
5046 for (j
= 0; j
< MAX_NR_ZONES
; j
++) {
5047 struct zone
*zone
= pgdat
->node_zones
+ j
;
5048 unsigned long present_pages
= zone
->present_pages
;
5050 zone
->lowmem_reserve
[j
] = 0;
5054 struct zone
*lower_zone
;
5058 if (sysctl_lowmem_reserve_ratio
[idx
] < 1)
5059 sysctl_lowmem_reserve_ratio
[idx
] = 1;
5061 lower_zone
= pgdat
->node_zones
+ idx
;
5062 lower_zone
->lowmem_reserve
[j
] = present_pages
/
5063 sysctl_lowmem_reserve_ratio
[idx
];
5064 present_pages
+= lower_zone
->present_pages
;
5069 /* update totalreserve_pages */
5070 calculate_totalreserve_pages();
5073 static void __setup_per_zone_wmarks(void)
5075 unsigned long pages_min
= min_free_kbytes
>> (PAGE_SHIFT
- 10);
5076 unsigned long lowmem_pages
= 0;
5078 unsigned long flags
;
5080 /* Calculate total number of !ZONE_HIGHMEM pages */
5081 for_each_zone(zone
) {
5082 if (!is_highmem(zone
))
5083 lowmem_pages
+= zone
->present_pages
;
5086 for_each_zone(zone
) {
5089 spin_lock_irqsave(&zone
->lock
, flags
);
5090 tmp
= (u64
)pages_min
* zone
->present_pages
;
5091 do_div(tmp
, lowmem_pages
);
5092 if (is_highmem(zone
)) {
5094 * __GFP_HIGH and PF_MEMALLOC allocations usually don't
5095 * need highmem pages, so cap pages_min to a small
5098 * The WMARK_HIGH-WMARK_LOW and (WMARK_LOW-WMARK_MIN)
5099 * deltas controls asynch page reclaim, and so should
5100 * not be capped for highmem.
5104 min_pages
= zone
->present_pages
/ 1024;
5105 if (min_pages
< SWAP_CLUSTER_MAX
)
5106 min_pages
= SWAP_CLUSTER_MAX
;
5107 if (min_pages
> 128)
5109 zone
->watermark
[WMARK_MIN
] = min_pages
;
5112 * If it's a lowmem zone, reserve a number of pages
5113 * proportionate to the zone's size.
5115 zone
->watermark
[WMARK_MIN
] = tmp
;
5118 zone
->watermark
[WMARK_LOW
] = min_wmark_pages(zone
) + (tmp
>> 2);
5119 zone
->watermark
[WMARK_HIGH
] = min_wmark_pages(zone
) + (tmp
>> 1);
5121 zone
->watermark
[WMARK_MIN
] += cma_wmark_pages(zone
);
5122 zone
->watermark
[WMARK_LOW
] += cma_wmark_pages(zone
);
5123 zone
->watermark
[WMARK_HIGH
] += cma_wmark_pages(zone
);
5125 setup_zone_migrate_reserve(zone
);
5126 spin_unlock_irqrestore(&zone
->lock
, flags
);
5129 /* update totalreserve_pages */
5130 calculate_totalreserve_pages();
5134 * setup_per_zone_wmarks - called when min_free_kbytes changes
5135 * or when memory is hot-{added|removed}
5137 * Ensures that the watermark[min,low,high] values for each zone are set
5138 * correctly with respect to min_free_kbytes.
5140 void setup_per_zone_wmarks(void)
5142 mutex_lock(&zonelists_mutex
);
5143 __setup_per_zone_wmarks();
5144 mutex_unlock(&zonelists_mutex
);
5148 * The inactive anon list should be small enough that the VM never has to
5149 * do too much work, but large enough that each inactive page has a chance
5150 * to be referenced again before it is swapped out.
5152 * The inactive_anon ratio is the target ratio of ACTIVE_ANON to
5153 * INACTIVE_ANON pages on this zone's LRU, maintained by the
5154 * pageout code. A zone->inactive_ratio of 3 means 3:1 or 25% of
5155 * the anonymous pages are kept on the inactive list.
5158 * memory ratio inactive anon
5159 * -------------------------------------
5168 static void __meminit
calculate_zone_inactive_ratio(struct zone
*zone
)
5170 unsigned int gb
, ratio
;
5172 /* Zone size in gigabytes */
5173 gb
= zone
->present_pages
>> (30 - PAGE_SHIFT
);
5175 ratio
= int_sqrt(10 * gb
);
5179 zone
->inactive_ratio
= ratio
;
5182 static void __meminit
setup_per_zone_inactive_ratio(void)
5187 calculate_zone_inactive_ratio(zone
);
5191 * Initialise min_free_kbytes.
5193 * For small machines we want it small (128k min). For large machines
5194 * we want it large (64MB max). But it is not linear, because network
5195 * bandwidth does not increase linearly with machine size. We use
5197 * min_free_kbytes = 4 * sqrt(lowmem_kbytes), for better accuracy:
5198 * min_free_kbytes = sqrt(lowmem_kbytes * 16)
5214 int __meminit
init_per_zone_wmark_min(void)
5216 unsigned long lowmem_kbytes
;
5218 lowmem_kbytes
= nr_free_buffer_pages() * (PAGE_SIZE
>> 10);
5220 min_free_kbytes
= int_sqrt(lowmem_kbytes
* 16);
5221 if (min_free_kbytes
< 128)
5222 min_free_kbytes
= 128;
5223 if (min_free_kbytes
> 65536)
5224 min_free_kbytes
= 65536;
5225 setup_per_zone_wmarks();
5226 refresh_zone_stat_thresholds();
5227 setup_per_zone_lowmem_reserve();
5228 setup_per_zone_inactive_ratio();
5231 module_init(init_per_zone_wmark_min
)
5234 * min_free_kbytes_sysctl_handler - just a wrapper around proc_dointvec() so
5235 * that we can call two helper functions whenever min_free_kbytes
5238 int min_free_kbytes_sysctl_handler(ctl_table
*table
, int write
,
5239 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
5241 proc_dointvec(table
, write
, buffer
, length
, ppos
);
5243 setup_per_zone_wmarks();
5248 int sysctl_min_unmapped_ratio_sysctl_handler(ctl_table
*table
, int write
,
5249 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
5254 rc
= proc_dointvec_minmax(table
, write
, buffer
, length
, ppos
);
5259 zone
->min_unmapped_pages
= (zone
->present_pages
*
5260 sysctl_min_unmapped_ratio
) / 100;
5264 int sysctl_min_slab_ratio_sysctl_handler(ctl_table
*table
, int write
,
5265 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
5270 rc
= proc_dointvec_minmax(table
, write
, buffer
, length
, ppos
);
5275 zone
->min_slab_pages
= (zone
->present_pages
*
5276 sysctl_min_slab_ratio
) / 100;
5282 * lowmem_reserve_ratio_sysctl_handler - just a wrapper around
5283 * proc_dointvec() so that we can call setup_per_zone_lowmem_reserve()
5284 * whenever sysctl_lowmem_reserve_ratio changes.
5286 * The reserve ratio obviously has absolutely no relation with the
5287 * minimum watermarks. The lowmem reserve ratio can only make sense
5288 * if in function of the boot time zone sizes.
5290 int lowmem_reserve_ratio_sysctl_handler(ctl_table
*table
, int write
,
5291 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
5293 proc_dointvec_minmax(table
, write
, buffer
, length
, ppos
);
5294 setup_per_zone_lowmem_reserve();
5299 * percpu_pagelist_fraction - changes the pcp->high for each zone on each
5300 * cpu. It is the fraction of total pages in each zone that a hot per cpu pagelist
5301 * can have before it gets flushed back to buddy allocator.
5304 int percpu_pagelist_fraction_sysctl_handler(ctl_table
*table
, int write
,
5305 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
5311 ret
= proc_dointvec_minmax(table
, write
, buffer
, length
, ppos
);
5312 if (!write
|| (ret
< 0))
5314 for_each_populated_zone(zone
) {
5315 for_each_possible_cpu(cpu
) {
5317 high
= zone
->present_pages
/ percpu_pagelist_fraction
;
5318 setup_pagelist_highmark(
5319 per_cpu_ptr(zone
->pageset
, cpu
), high
);
5325 int hashdist
= HASHDIST_DEFAULT
;
5328 static int __init
set_hashdist(char *str
)
5332 hashdist
= simple_strtoul(str
, &str
, 0);
5335 __setup("hashdist=", set_hashdist
);
5339 * allocate a large system hash table from bootmem
5340 * - it is assumed that the hash table must contain an exact power-of-2
5341 * quantity of entries
5342 * - limit is the number of hash buckets, not the total allocation size
5344 void *__init
alloc_large_system_hash(const char *tablename
,
5345 unsigned long bucketsize
,
5346 unsigned long numentries
,
5349 unsigned int *_hash_shift
,
5350 unsigned int *_hash_mask
,
5351 unsigned long low_limit
,
5352 unsigned long high_limit
)
5354 unsigned long long max
= high_limit
;
5355 unsigned long log2qty
, size
;
5358 /* allow the kernel cmdline to have a say */
5360 /* round applicable memory size up to nearest megabyte */
5361 numentries
= nr_kernel_pages
;
5362 numentries
+= (1UL << (20 - PAGE_SHIFT
)) - 1;
5363 numentries
>>= 20 - PAGE_SHIFT
;
5364 numentries
<<= 20 - PAGE_SHIFT
;
5366 /* limit to 1 bucket per 2^scale bytes of low memory */
5367 if (scale
> PAGE_SHIFT
)
5368 numentries
>>= (scale
- PAGE_SHIFT
);
5370 numentries
<<= (PAGE_SHIFT
- scale
);
5372 /* Make sure we've got at least a 0-order allocation.. */
5373 if (unlikely(flags
& HASH_SMALL
)) {
5374 /* Makes no sense without HASH_EARLY */
5375 WARN_ON(!(flags
& HASH_EARLY
));
5376 if (!(numentries
>> *_hash_shift
)) {
5377 numentries
= 1UL << *_hash_shift
;
5378 BUG_ON(!numentries
);
5380 } else if (unlikely((numentries
* bucketsize
) < PAGE_SIZE
))
5381 numentries
= PAGE_SIZE
/ bucketsize
;
5383 numentries
= roundup_pow_of_two(numentries
);
5385 /* limit allocation size to 1/16 total memory by default */
5387 max
= ((unsigned long long)nr_all_pages
<< PAGE_SHIFT
) >> 4;
5388 do_div(max
, bucketsize
);
5390 max
= min(max
, 0x80000000ULL
);
5392 if (numentries
< low_limit
)
5393 numentries
= low_limit
;
5394 if (numentries
> max
)
5397 log2qty
= ilog2(numentries
);
5400 size
= bucketsize
<< log2qty
;
5401 if (flags
& HASH_EARLY
)
5402 table
= alloc_bootmem_nopanic(size
);
5404 table
= __vmalloc(size
, GFP_ATOMIC
, PAGE_KERNEL
);
5407 * If bucketsize is not a power-of-two, we may free
5408 * some pages at the end of hash table which
5409 * alloc_pages_exact() automatically does
5411 if (get_order(size
) < MAX_ORDER
) {
5412 table
= alloc_pages_exact(size
, GFP_ATOMIC
);
5413 kmemleak_alloc(table
, size
, 1, GFP_ATOMIC
);
5416 } while (!table
&& size
> PAGE_SIZE
&& --log2qty
);
5419 panic("Failed to allocate %s hash table\n", tablename
);
5421 printk(KERN_INFO
"%s hash table entries: %ld (order: %d, %lu bytes)\n",
5424 ilog2(size
) - PAGE_SHIFT
,
5428 *_hash_shift
= log2qty
;
5430 *_hash_mask
= (1 << log2qty
) - 1;
5435 /* Return a pointer to the bitmap storing bits affecting a block of pages */
5436 static inline unsigned long *get_pageblock_bitmap(struct zone
*zone
,
5439 #ifdef CONFIG_SPARSEMEM
5440 return __pfn_to_section(pfn
)->pageblock_flags
;
5442 return zone
->pageblock_flags
;
5443 #endif /* CONFIG_SPARSEMEM */
5446 static inline int pfn_to_bitidx(struct zone
*zone
, unsigned long pfn
)
5448 #ifdef CONFIG_SPARSEMEM
5449 pfn
&= (PAGES_PER_SECTION
-1);
5450 return (pfn
>> pageblock_order
) * NR_PAGEBLOCK_BITS
;
5452 pfn
= pfn
- zone
->zone_start_pfn
;
5453 return (pfn
>> pageblock_order
) * NR_PAGEBLOCK_BITS
;
5454 #endif /* CONFIG_SPARSEMEM */
5458 * get_pageblock_flags_group - Return the requested group of flags for the pageblock_nr_pages block of pages
5459 * @page: The page within the block of interest
5460 * @start_bitidx: The first bit of interest to retrieve
5461 * @end_bitidx: The last bit of interest
5462 * returns pageblock_bits flags
5464 unsigned long get_pageblock_flags_group(struct page
*page
,
5465 int start_bitidx
, int end_bitidx
)
5468 unsigned long *bitmap
;
5469 unsigned long pfn
, bitidx
;
5470 unsigned long flags
= 0;
5471 unsigned long value
= 1;
5473 zone
= page_zone(page
);
5474 pfn
= page_to_pfn(page
);
5475 bitmap
= get_pageblock_bitmap(zone
, pfn
);
5476 bitidx
= pfn_to_bitidx(zone
, pfn
);
5478 for (; start_bitidx
<= end_bitidx
; start_bitidx
++, value
<<= 1)
5479 if (test_bit(bitidx
+ start_bitidx
, bitmap
))
5486 * set_pageblock_flags_group - Set the requested group of flags for a pageblock_nr_pages block of pages
5487 * @page: The page within the block of interest
5488 * @start_bitidx: The first bit of interest
5489 * @end_bitidx: The last bit of interest
5490 * @flags: The flags to set
5492 void set_pageblock_flags_group(struct page
*page
, unsigned long flags
,
5493 int start_bitidx
, int end_bitidx
)
5496 unsigned long *bitmap
;
5497 unsigned long pfn
, bitidx
;
5498 unsigned long value
= 1;
5500 zone
= page_zone(page
);
5501 pfn
= page_to_pfn(page
);
5502 bitmap
= get_pageblock_bitmap(zone
, pfn
);
5503 bitidx
= pfn_to_bitidx(zone
, pfn
);
5504 VM_BUG_ON(pfn
< zone
->zone_start_pfn
);
5505 VM_BUG_ON(pfn
>= zone
->zone_start_pfn
+ zone
->spanned_pages
);
5507 for (; start_bitidx
<= end_bitidx
; start_bitidx
++, value
<<= 1)
5509 __set_bit(bitidx
+ start_bitidx
, bitmap
);
5511 __clear_bit(bitidx
+ start_bitidx
, bitmap
);
5515 * This function checks whether pageblock includes unmovable pages or not.
5516 * If @count is not zero, it is okay to include less @count unmovable pages
5518 * PageLRU check wihtout isolation or lru_lock could race so that
5519 * MIGRATE_MOVABLE block might include unmovable pages. It means you can't
5520 * expect this function should be exact.
5522 bool has_unmovable_pages(struct zone
*zone
, struct page
*page
, int count
)
5524 unsigned long pfn
, iter
, found
;
5528 * For avoiding noise data, lru_add_drain_all() should be called
5529 * If ZONE_MOVABLE, the zone never contains unmovable pages
5531 if (zone_idx(zone
) == ZONE_MOVABLE
)
5533 mt
= get_pageblock_migratetype(page
);
5534 if (mt
== MIGRATE_MOVABLE
|| is_migrate_cma(mt
))
5537 pfn
= page_to_pfn(page
);
5538 for (found
= 0, iter
= 0; iter
< pageblock_nr_pages
; iter
++) {
5539 unsigned long check
= pfn
+ iter
;
5541 if (!pfn_valid_within(check
))
5544 page
= pfn_to_page(check
);
5546 * We can't use page_count without pin a page
5547 * because another CPU can free compound page.
5548 * This check already skips compound tails of THP
5549 * because their page->_count is zero at all time.
5551 if (!atomic_read(&page
->_count
)) {
5552 if (PageBuddy(page
))
5553 iter
+= (1 << page_order(page
)) - 1;
5560 * If there are RECLAIMABLE pages, we need to check it.
5561 * But now, memory offline itself doesn't call shrink_slab()
5562 * and it still to be fixed.
5565 * If the page is not RAM, page_count()should be 0.
5566 * we don't need more check. This is an _used_ not-movable page.
5568 * The problematic thing here is PG_reserved pages. PG_reserved
5569 * is set to both of a memory hole page and a _used_ kernel
5578 bool is_pageblock_removable_nolock(struct page
*page
)
5584 * We have to be careful here because we are iterating over memory
5585 * sections which are not zone aware so we might end up outside of
5586 * the zone but still within the section.
5587 * We have to take care about the node as well. If the node is offline
5588 * its NODE_DATA will be NULL - see page_zone.
5590 if (!node_online(page_to_nid(page
)))
5593 zone
= page_zone(page
);
5594 pfn
= page_to_pfn(page
);
5595 if (zone
->zone_start_pfn
> pfn
||
5596 zone
->zone_start_pfn
+ zone
->spanned_pages
<= pfn
)
5599 return !has_unmovable_pages(zone
, page
, 0);
5604 static unsigned long pfn_max_align_down(unsigned long pfn
)
5606 return pfn
& ~(max_t(unsigned long, MAX_ORDER_NR_PAGES
,
5607 pageblock_nr_pages
) - 1);
5610 static unsigned long pfn_max_align_up(unsigned long pfn
)
5612 return ALIGN(pfn
, max_t(unsigned long, MAX_ORDER_NR_PAGES
,
5613 pageblock_nr_pages
));
5616 static struct page
*
5617 __alloc_contig_migrate_alloc(struct page
*page
, unsigned long private,
5620 gfp_t gfp_mask
= GFP_USER
| __GFP_MOVABLE
;
5622 if (PageHighMem(page
))
5623 gfp_mask
|= __GFP_HIGHMEM
;
5625 return alloc_page(gfp_mask
);
5628 /* [start, end) must belong to a single zone. */
5629 static int __alloc_contig_migrate_range(unsigned long start
, unsigned long end
)
5631 /* This function is based on compact_zone() from compaction.c. */
5633 unsigned long pfn
= start
;
5634 unsigned int tries
= 0;
5637 struct compact_control cc
= {
5638 .nr_migratepages
= 0,
5640 .zone
= page_zone(pfn_to_page(start
)),
5643 INIT_LIST_HEAD(&cc
.migratepages
);
5645 migrate_prep_local();
5647 while (pfn
< end
|| !list_empty(&cc
.migratepages
)) {
5648 if (fatal_signal_pending(current
)) {
5653 if (list_empty(&cc
.migratepages
)) {
5654 cc
.nr_migratepages
= 0;
5655 pfn
= isolate_migratepages_range(cc
.zone
, &cc
,
5662 } else if (++tries
== 5) {
5663 ret
= ret
< 0 ? ret
: -EBUSY
;
5667 ret
= migrate_pages(&cc
.migratepages
,
5668 __alloc_contig_migrate_alloc
,
5669 0, false, MIGRATE_SYNC
);
5672 putback_lru_pages(&cc
.migratepages
);
5673 return ret
> 0 ? 0 : ret
;
5677 * Update zone's cma pages counter used for watermark level calculation.
5679 static inline void __update_cma_watermarks(struct zone
*zone
, int count
)
5681 unsigned long flags
;
5682 spin_lock_irqsave(&zone
->lock
, flags
);
5683 zone
->min_cma_pages
+= count
;
5684 spin_unlock_irqrestore(&zone
->lock
, flags
);
5685 setup_per_zone_wmarks();
5689 * Trigger memory pressure bump to reclaim some pages in order to be able to
5690 * allocate 'count' pages in single page units. Does similar work as
5691 *__alloc_pages_slowpath() function.
5693 static int __reclaim_pages(struct zone
*zone
, gfp_t gfp_mask
, int count
)
5695 enum zone_type high_zoneidx
= gfp_zone(gfp_mask
);
5696 struct zonelist
*zonelist
= node_zonelist(0, gfp_mask
);
5697 int did_some_progress
= 0;
5701 * Increase level of watermarks to force kswapd do his job
5702 * to stabilise at new watermark level.
5704 __update_cma_watermarks(zone
, count
);
5706 /* Obey watermarks as if the page was being allocated */
5707 while (!zone_watermark_ok(zone
, 0, low_wmark_pages(zone
), 0, 0)) {
5708 wake_all_kswapd(order
, zonelist
, high_zoneidx
, zone_idx(zone
));
5710 did_some_progress
= __perform_reclaim(gfp_mask
, order
, zonelist
,
5712 if (!did_some_progress
) {
5713 /* Exhausted what can be done so it's blamo time */
5714 out_of_memory(zonelist
, gfp_mask
, order
, NULL
, false);
5718 /* Restore original watermark levels. */
5719 __update_cma_watermarks(zone
, -count
);
5725 * alloc_contig_range() -- tries to allocate given range of pages
5726 * @start: start PFN to allocate
5727 * @end: one-past-the-last PFN to allocate
5728 * @migratetype: migratetype of the underlaying pageblocks (either
5729 * #MIGRATE_MOVABLE or #MIGRATE_CMA). All pageblocks
5730 * in range must have the same migratetype and it must
5731 * be either of the two.
5733 * The PFN range does not have to be pageblock or MAX_ORDER_NR_PAGES
5734 * aligned, however it's the caller's responsibility to guarantee that
5735 * we are the only thread that changes migrate type of pageblocks the
5738 * The PFN range must belong to a single zone.
5740 * Returns zero on success or negative error code. On success all
5741 * pages which PFN is in [start, end) are allocated for the caller and
5742 * need to be freed with free_contig_range().
5744 int alloc_contig_range(unsigned long start
, unsigned long end
,
5745 unsigned migratetype
)
5747 struct zone
*zone
= page_zone(pfn_to_page(start
));
5748 unsigned long outer_start
, outer_end
;
5752 * What we do here is we mark all pageblocks in range as
5753 * MIGRATE_ISOLATE. Because pageblock and max order pages may
5754 * have different sizes, and due to the way page allocator
5755 * work, we align the range to biggest of the two pages so
5756 * that page allocator won't try to merge buddies from
5757 * different pageblocks and change MIGRATE_ISOLATE to some
5758 * other migration type.
5760 * Once the pageblocks are marked as MIGRATE_ISOLATE, we
5761 * migrate the pages from an unaligned range (ie. pages that
5762 * we are interested in). This will put all the pages in
5763 * range back to page allocator as MIGRATE_ISOLATE.
5765 * When this is done, we take the pages in range from page
5766 * allocator removing them from the buddy system. This way
5767 * page allocator will never consider using them.
5769 * This lets us mark the pageblocks back as
5770 * MIGRATE_CMA/MIGRATE_MOVABLE so that free pages in the
5771 * aligned range but not in the unaligned, original range are
5772 * put back to page allocator so that buddy can use them.
5775 ret
= start_isolate_page_range(pfn_max_align_down(start
),
5776 pfn_max_align_up(end
), migratetype
);
5780 ret
= __alloc_contig_migrate_range(start
, end
);
5785 * Pages from [start, end) are within a MAX_ORDER_NR_PAGES
5786 * aligned blocks that are marked as MIGRATE_ISOLATE. What's
5787 * more, all pages in [start, end) are free in page allocator.
5788 * What we are going to do is to allocate all pages from
5789 * [start, end) (that is remove them from page allocator).
5791 * The only problem is that pages at the beginning and at the
5792 * end of interesting range may be not aligned with pages that
5793 * page allocator holds, ie. they can be part of higher order
5794 * pages. Because of this, we reserve the bigger range and
5795 * once this is done free the pages we are not interested in.
5797 * We don't have to hold zone->lock here because the pages are
5798 * isolated thus they won't get removed from buddy.
5801 lru_add_drain_all();
5805 outer_start
= start
;
5806 while (!PageBuddy(pfn_to_page(outer_start
))) {
5807 if (++order
>= MAX_ORDER
) {
5811 outer_start
&= ~0UL << order
;
5814 /* Make sure the range is really isolated. */
5815 if (test_pages_isolated(outer_start
, end
)) {
5816 pr_warn("alloc_contig_range test_pages_isolated(%lx, %lx) failed\n",
5823 * Reclaim enough pages to make sure that contiguous allocation
5824 * will not starve the system.
5826 __reclaim_pages(zone
, GFP_HIGHUSER_MOVABLE
, end
-start
);
5828 /* Grab isolated pages from freelists. */
5829 outer_end
= isolate_freepages_range(outer_start
, end
);
5835 /* Free head and tail (if any) */
5836 if (start
!= outer_start
)
5837 free_contig_range(outer_start
, start
- outer_start
);
5838 if (end
!= outer_end
)
5839 free_contig_range(end
, outer_end
- end
);
5842 undo_isolate_page_range(pfn_max_align_down(start
),
5843 pfn_max_align_up(end
), migratetype
);
5847 void free_contig_range(unsigned long pfn
, unsigned nr_pages
)
5849 for (; nr_pages
--; ++pfn
)
5850 __free_page(pfn_to_page(pfn
));
5854 #ifdef CONFIG_MEMORY_HOTPLUG
5855 static int __meminit
__zone_pcp_update(void *data
)
5857 struct zone
*zone
= data
;
5859 unsigned long batch
= zone_batchsize(zone
), flags
;
5861 for_each_possible_cpu(cpu
) {
5862 struct per_cpu_pageset
*pset
;
5863 struct per_cpu_pages
*pcp
;
5865 pset
= per_cpu_ptr(zone
->pageset
, cpu
);
5868 local_irq_save(flags
);
5870 free_pcppages_bulk(zone
, pcp
->count
, pcp
);
5871 setup_pageset(pset
, batch
);
5872 local_irq_restore(flags
);
5877 void __meminit
zone_pcp_update(struct zone
*zone
)
5879 stop_machine(__zone_pcp_update
, zone
, NULL
);
5883 #ifdef CONFIG_MEMORY_HOTREMOVE
5884 void zone_pcp_reset(struct zone
*zone
)
5886 unsigned long flags
;
5888 /* avoid races with drain_pages() */
5889 local_irq_save(flags
);
5890 if (zone
->pageset
!= &boot_pageset
) {
5891 free_percpu(zone
->pageset
);
5892 zone
->pageset
= &boot_pageset
;
5894 local_irq_restore(flags
);
5898 * All pages in the range must be isolated before calling this.
5901 __offline_isolated_pages(unsigned long start_pfn
, unsigned long end_pfn
)
5907 unsigned long flags
;
5908 /* find the first valid pfn */
5909 for (pfn
= start_pfn
; pfn
< end_pfn
; pfn
++)
5914 zone
= page_zone(pfn_to_page(pfn
));
5915 spin_lock_irqsave(&zone
->lock
, flags
);
5917 while (pfn
< end_pfn
) {
5918 if (!pfn_valid(pfn
)) {
5922 page
= pfn_to_page(pfn
);
5923 BUG_ON(page_count(page
));
5924 BUG_ON(!PageBuddy(page
));
5925 order
= page_order(page
);
5926 #ifdef CONFIG_DEBUG_VM
5927 printk(KERN_INFO
"remove from free list %lx %d %lx\n",
5928 pfn
, 1 << order
, end_pfn
);
5930 list_del(&page
->lru
);
5931 rmv_page_order(page
);
5932 zone
->free_area
[order
].nr_free
--;
5933 __mod_zone_page_state(zone
, NR_FREE_PAGES
,
5935 for (i
= 0; i
< (1 << order
); i
++)
5936 SetPageReserved((page
+i
));
5937 pfn
+= (1 << order
);
5939 spin_unlock_irqrestore(&zone
->lock
, flags
);
5943 #ifdef CONFIG_MEMORY_FAILURE
5944 bool is_free_buddy_page(struct page
*page
)
5946 struct zone
*zone
= page_zone(page
);
5947 unsigned long pfn
= page_to_pfn(page
);
5948 unsigned long flags
;
5951 spin_lock_irqsave(&zone
->lock
, flags
);
5952 for (order
= 0; order
< MAX_ORDER
; order
++) {
5953 struct page
*page_head
= page
- (pfn
& ((1 << order
) - 1));
5955 if (PageBuddy(page_head
) && page_order(page_head
) >= order
)
5958 spin_unlock_irqrestore(&zone
->lock
, flags
);
5960 return order
< MAX_ORDER
;
5964 static const struct trace_print_flags pageflag_names
[] = {
5965 {1UL << PG_locked
, "locked" },
5966 {1UL << PG_error
, "error" },
5967 {1UL << PG_referenced
, "referenced" },
5968 {1UL << PG_uptodate
, "uptodate" },
5969 {1UL << PG_dirty
, "dirty" },
5970 {1UL << PG_lru
, "lru" },
5971 {1UL << PG_active
, "active" },
5972 {1UL << PG_slab
, "slab" },
5973 {1UL << PG_owner_priv_1
, "owner_priv_1" },
5974 {1UL << PG_arch_1
, "arch_1" },
5975 {1UL << PG_reserved
, "reserved" },
5976 {1UL << PG_private
, "private" },
5977 {1UL << PG_private_2
, "private_2" },
5978 {1UL << PG_writeback
, "writeback" },
5979 #ifdef CONFIG_PAGEFLAGS_EXTENDED
5980 {1UL << PG_head
, "head" },
5981 {1UL << PG_tail
, "tail" },
5983 {1UL << PG_compound
, "compound" },
5985 {1UL << PG_swapcache
, "swapcache" },
5986 {1UL << PG_mappedtodisk
, "mappedtodisk" },
5987 {1UL << PG_reclaim
, "reclaim" },
5988 {1UL << PG_swapbacked
, "swapbacked" },
5989 {1UL << PG_unevictable
, "unevictable" },
5991 {1UL << PG_mlocked
, "mlocked" },
5993 #ifdef CONFIG_ARCH_USES_PG_UNCACHED
5994 {1UL << PG_uncached
, "uncached" },
5996 #ifdef CONFIG_MEMORY_FAILURE
5997 {1UL << PG_hwpoison
, "hwpoison" },
5999 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
6000 {1UL << PG_compound_lock
, "compound_lock" },
6004 static void dump_page_flags(unsigned long flags
)
6006 const char *delim
= "";
6010 BUILD_BUG_ON(ARRAY_SIZE(pageflag_names
) != __NR_PAGEFLAGS
);
6012 printk(KERN_ALERT
"page flags: %#lx(", flags
);
6014 /* remove zone id */
6015 flags
&= (1UL << NR_PAGEFLAGS
) - 1;
6017 for (i
= 0; i
< ARRAY_SIZE(pageflag_names
) && flags
; i
++) {
6019 mask
= pageflag_names
[i
].mask
;
6020 if ((flags
& mask
) != mask
)
6024 printk("%s%s", delim
, pageflag_names
[i
].name
);
6028 /* check for left over flags */
6030 printk("%s%#lx", delim
, flags
);
6035 void dump_page(struct page
*page
)
6038 "page:%p count:%d mapcount:%d mapping:%p index:%#lx\n",
6039 page
, atomic_read(&page
->_count
), page_mapcount(page
),
6040 page
->mapping
, page
->index
);
6041 dump_page_flags(page
->flags
);
6042 mem_cgroup_print_bad_page(page
);