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/mm_inline.h>
60 #include <linux/migrate.h>
61 #include <linux/page-debug-flags.h>
62 #include <linux/hugetlb.h>
63 #include <linux/sched/rt.h>
65 #include <asm/sections.h>
66 #include <asm/tlbflush.h>
67 #include <asm/div64.h>
70 /* prevent >1 _updater_ of zone percpu pageset ->high and ->batch fields */
71 static DEFINE_MUTEX(pcp_batch_high_lock
);
73 #ifdef CONFIG_USE_PERCPU_NUMA_NODE_ID
74 DEFINE_PER_CPU(int, numa_node
);
75 EXPORT_PER_CPU_SYMBOL(numa_node
);
78 #ifdef CONFIG_HAVE_MEMORYLESS_NODES
80 * N.B., Do NOT reference the '_numa_mem_' per cpu variable directly.
81 * It will not be defined when CONFIG_HAVE_MEMORYLESS_NODES is not defined.
82 * Use the accessor functions set_numa_mem(), numa_mem_id() and cpu_to_mem()
83 * defined in <linux/topology.h>.
85 DEFINE_PER_CPU(int, _numa_mem_
); /* Kernel "local memory" node */
86 EXPORT_PER_CPU_SYMBOL(_numa_mem_
);
90 * Array of node states.
92 nodemask_t node_states
[NR_NODE_STATES
] __read_mostly
= {
93 [N_POSSIBLE
] = NODE_MASK_ALL
,
94 [N_ONLINE
] = { { [0] = 1UL } },
96 [N_NORMAL_MEMORY
] = { { [0] = 1UL } },
98 [N_HIGH_MEMORY
] = { { [0] = 1UL } },
100 #ifdef CONFIG_MOVABLE_NODE
101 [N_MEMORY
] = { { [0] = 1UL } },
103 [N_CPU
] = { { [0] = 1UL } },
106 EXPORT_SYMBOL(node_states
);
108 /* Protect totalram_pages and zone->managed_pages */
109 static DEFINE_SPINLOCK(managed_page_count_lock
);
111 unsigned long totalram_pages __read_mostly
;
112 unsigned long totalreserve_pages __read_mostly
;
114 * When calculating the number of globally allowed dirty pages, there
115 * is a certain number of per-zone reserves that should not be
116 * considered dirtyable memory. This is the sum of those reserves
117 * over all existing zones that contribute dirtyable memory.
119 unsigned long dirty_balance_reserve __read_mostly
;
121 int percpu_pagelist_fraction
;
122 gfp_t gfp_allowed_mask __read_mostly
= GFP_BOOT_MASK
;
124 #ifdef CONFIG_PM_SLEEP
126 * The following functions are used by the suspend/hibernate code to temporarily
127 * change gfp_allowed_mask in order to avoid using I/O during memory allocations
128 * while devices are suspended. To avoid races with the suspend/hibernate code,
129 * they should always be called with pm_mutex held (gfp_allowed_mask also should
130 * only be modified with pm_mutex held, unless the suspend/hibernate code is
131 * guaranteed not to run in parallel with that modification).
134 static gfp_t saved_gfp_mask
;
136 void pm_restore_gfp_mask(void)
138 WARN_ON(!mutex_is_locked(&pm_mutex
));
139 if (saved_gfp_mask
) {
140 gfp_allowed_mask
= saved_gfp_mask
;
145 void pm_restrict_gfp_mask(void)
147 WARN_ON(!mutex_is_locked(&pm_mutex
));
148 WARN_ON(saved_gfp_mask
);
149 saved_gfp_mask
= gfp_allowed_mask
;
150 gfp_allowed_mask
&= ~GFP_IOFS
;
153 bool pm_suspended_storage(void)
155 if ((gfp_allowed_mask
& GFP_IOFS
) == GFP_IOFS
)
159 #endif /* CONFIG_PM_SLEEP */
161 #ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
162 int pageblock_order __read_mostly
;
165 static void __free_pages_ok(struct page
*page
, unsigned int order
);
168 * results with 256, 32 in the lowmem_reserve sysctl:
169 * 1G machine -> (16M dma, 800M-16M normal, 1G-800M high)
170 * 1G machine -> (16M dma, 784M normal, 224M high)
171 * NORMAL allocation will leave 784M/256 of ram reserved in the ZONE_DMA
172 * HIGHMEM allocation will leave 224M/32 of ram reserved in ZONE_NORMAL
173 * HIGHMEM allocation will (224M+784M)/256 of ram reserved in ZONE_DMA
175 * TBD: should special case ZONE_DMA32 machines here - in those we normally
176 * don't need any ZONE_NORMAL reservation
178 int sysctl_lowmem_reserve_ratio
[MAX_NR_ZONES
-1] = {
179 #ifdef CONFIG_ZONE_DMA
182 #ifdef CONFIG_ZONE_DMA32
185 #ifdef CONFIG_HIGHMEM
191 EXPORT_SYMBOL(totalram_pages
);
193 static char * const zone_names
[MAX_NR_ZONES
] = {
194 #ifdef CONFIG_ZONE_DMA
197 #ifdef CONFIG_ZONE_DMA32
201 #ifdef CONFIG_HIGHMEM
207 int min_free_kbytes
= 1024;
208 int user_min_free_kbytes
= -1;
210 static unsigned long __meminitdata nr_kernel_pages
;
211 static unsigned long __meminitdata nr_all_pages
;
212 static unsigned long __meminitdata dma_reserve
;
214 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
215 static unsigned long __meminitdata arch_zone_lowest_possible_pfn
[MAX_NR_ZONES
];
216 static unsigned long __meminitdata arch_zone_highest_possible_pfn
[MAX_NR_ZONES
];
217 static unsigned long __initdata required_kernelcore
;
218 static unsigned long __initdata required_movablecore
;
219 static unsigned long __meminitdata zone_movable_pfn
[MAX_NUMNODES
];
221 /* movable_zone is the "real" zone pages in ZONE_MOVABLE are taken from */
223 EXPORT_SYMBOL(movable_zone
);
224 #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
227 int nr_node_ids __read_mostly
= MAX_NUMNODES
;
228 int nr_online_nodes __read_mostly
= 1;
229 EXPORT_SYMBOL(nr_node_ids
);
230 EXPORT_SYMBOL(nr_online_nodes
);
233 int page_group_by_mobility_disabled __read_mostly
;
235 void set_pageblock_migratetype(struct page
*page
, int migratetype
)
237 if (unlikely(page_group_by_mobility_disabled
&&
238 migratetype
< MIGRATE_PCPTYPES
))
239 migratetype
= MIGRATE_UNMOVABLE
;
241 set_pageblock_flags_group(page
, (unsigned long)migratetype
,
242 PB_migrate
, PB_migrate_end
);
245 bool oom_killer_disabled __read_mostly
;
247 #ifdef CONFIG_DEBUG_VM
248 static int page_outside_zone_boundaries(struct zone
*zone
, struct page
*page
)
252 unsigned long pfn
= page_to_pfn(page
);
253 unsigned long sp
, start_pfn
;
256 seq
= zone_span_seqbegin(zone
);
257 start_pfn
= zone
->zone_start_pfn
;
258 sp
= zone
->spanned_pages
;
259 if (!zone_spans_pfn(zone
, pfn
))
261 } while (zone_span_seqretry(zone
, seq
));
264 pr_err("page %lu outside zone [ %lu - %lu ]\n",
265 pfn
, start_pfn
, start_pfn
+ sp
);
270 static int page_is_consistent(struct zone
*zone
, struct page
*page
)
272 if (!pfn_valid_within(page_to_pfn(page
)))
274 if (zone
!= page_zone(page
))
280 * Temporary debugging check for pages not lying within a given zone.
282 static int bad_range(struct zone
*zone
, struct page
*page
)
284 if (page_outside_zone_boundaries(zone
, page
))
286 if (!page_is_consistent(zone
, page
))
292 static inline int bad_range(struct zone
*zone
, struct page
*page
)
298 static void bad_page(struct page
*page
, char *reason
, unsigned long bad_flags
)
300 static unsigned long resume
;
301 static unsigned long nr_shown
;
302 static unsigned long nr_unshown
;
304 /* Don't complain about poisoned pages */
305 if (PageHWPoison(page
)) {
306 page_mapcount_reset(page
); /* remove PageBuddy */
311 * Allow a burst of 60 reports, then keep quiet for that minute;
312 * or allow a steady drip of one report per second.
314 if (nr_shown
== 60) {
315 if (time_before(jiffies
, resume
)) {
321 "BUG: Bad page state: %lu messages suppressed\n",
328 resume
= jiffies
+ 60 * HZ
;
330 printk(KERN_ALERT
"BUG: Bad page state in process %s pfn:%05lx\n",
331 current
->comm
, page_to_pfn(page
));
332 dump_page_badflags(page
, reason
, bad_flags
);
337 /* Leave bad fields for debug, except PageBuddy could make trouble */
338 page_mapcount_reset(page
); /* remove PageBuddy */
339 add_taint(TAINT_BAD_PAGE
, LOCKDEP_NOW_UNRELIABLE
);
343 * Higher-order pages are called "compound pages". They are structured thusly:
345 * The first PAGE_SIZE page is called the "head page".
347 * The remaining PAGE_SIZE pages are called "tail pages".
349 * All pages have PG_compound set. All tail pages have their ->first_page
350 * pointing at the head page.
352 * The first tail page's ->lru.next holds the address of the compound page's
353 * put_page() function. Its ->lru.prev holds the order of allocation.
354 * This usage means that zero-order pages may not be compound.
357 static void free_compound_page(struct page
*page
)
359 __free_pages_ok(page
, compound_order(page
));
362 void prep_compound_page(struct page
*page
, unsigned long order
)
365 int nr_pages
= 1 << order
;
367 set_compound_page_dtor(page
, free_compound_page
);
368 set_compound_order(page
, order
);
370 for (i
= 1; i
< nr_pages
; i
++) {
371 struct page
*p
= page
+ i
;
372 set_page_count(p
, 0);
373 p
->first_page
= page
;
374 /* Make sure p->first_page is always valid for PageTail() */
380 /* update __split_huge_page_refcount if you change this function */
381 static int destroy_compound_page(struct page
*page
, unsigned long order
)
384 int nr_pages
= 1 << order
;
387 if (unlikely(compound_order(page
) != order
)) {
388 bad_page(page
, "wrong compound order", 0);
392 __ClearPageHead(page
);
394 for (i
= 1; i
< nr_pages
; i
++) {
395 struct page
*p
= page
+ i
;
397 if (unlikely(!PageTail(p
))) {
398 bad_page(page
, "PageTail not set", 0);
400 } else if (unlikely(p
->first_page
!= page
)) {
401 bad_page(page
, "first_page not consistent", 0);
410 static inline void prep_zero_page(struct page
*page
, int order
, gfp_t gfp_flags
)
415 * clear_highpage() will use KM_USER0, so it's a bug to use __GFP_ZERO
416 * and __GFP_HIGHMEM from hard or soft interrupt context.
418 VM_BUG_ON((gfp_flags
& __GFP_HIGHMEM
) && in_interrupt());
419 for (i
= 0; i
< (1 << order
); i
++)
420 clear_highpage(page
+ i
);
423 #ifdef CONFIG_DEBUG_PAGEALLOC
424 unsigned int _debug_guardpage_minorder
;
426 static int __init
debug_guardpage_minorder_setup(char *buf
)
430 if (kstrtoul(buf
, 10, &res
) < 0 || res
> MAX_ORDER
/ 2) {
431 printk(KERN_ERR
"Bad debug_guardpage_minorder value\n");
434 _debug_guardpage_minorder
= res
;
435 printk(KERN_INFO
"Setting debug_guardpage_minorder to %lu\n", res
);
438 __setup("debug_guardpage_minorder=", debug_guardpage_minorder_setup
);
440 static inline void set_page_guard_flag(struct page
*page
)
442 __set_bit(PAGE_DEBUG_FLAG_GUARD
, &page
->debug_flags
);
445 static inline void clear_page_guard_flag(struct page
*page
)
447 __clear_bit(PAGE_DEBUG_FLAG_GUARD
, &page
->debug_flags
);
450 static inline void set_page_guard_flag(struct page
*page
) { }
451 static inline void clear_page_guard_flag(struct page
*page
) { }
454 static inline void set_page_order(struct page
*page
, int order
)
456 set_page_private(page
, order
);
457 __SetPageBuddy(page
);
460 static inline void rmv_page_order(struct page
*page
)
462 __ClearPageBuddy(page
);
463 set_page_private(page
, 0);
467 * Locate the struct page for both the matching buddy in our
468 * pair (buddy1) and the combined O(n+1) page they form (page).
470 * 1) Any buddy B1 will have an order O twin B2 which satisfies
471 * the following equation:
473 * For example, if the starting buddy (buddy2) is #8 its order
475 * B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10
477 * 2) Any buddy B will have an order O+1 parent P which
478 * satisfies the following equation:
481 * Assumption: *_mem_map is contiguous at least up to MAX_ORDER
483 static inline unsigned long
484 __find_buddy_index(unsigned long page_idx
, unsigned int order
)
486 return page_idx
^ (1 << order
);
490 * This function checks whether a page is free && is the buddy
491 * we can do coalesce a page and its buddy if
492 * (a) the buddy is not in a hole &&
493 * (b) the buddy is in the buddy system &&
494 * (c) a page and its buddy have the same order &&
495 * (d) a page and its buddy are in the same zone.
497 * For recording whether a page is in the buddy system, we set ->_mapcount
498 * PAGE_BUDDY_MAPCOUNT_VALUE.
499 * Setting, clearing, and testing _mapcount PAGE_BUDDY_MAPCOUNT_VALUE is
500 * serialized by zone->lock.
502 * For recording page's order, we use page_private(page).
504 static inline int page_is_buddy(struct page
*page
, struct page
*buddy
,
507 if (!pfn_valid_within(page_to_pfn(buddy
)))
510 if (page_zone_id(page
) != page_zone_id(buddy
))
513 if (page_is_guard(buddy
) && page_order(buddy
) == order
) {
514 VM_BUG_ON_PAGE(page_count(buddy
) != 0, buddy
);
518 if (PageBuddy(buddy
) && page_order(buddy
) == order
) {
519 VM_BUG_ON_PAGE(page_count(buddy
) != 0, buddy
);
526 * Freeing function for a buddy system allocator.
528 * The concept of a buddy system is to maintain direct-mapped table
529 * (containing bit values) for memory blocks of various "orders".
530 * The bottom level table contains the map for the smallest allocatable
531 * units of memory (here, pages), and each level above it describes
532 * pairs of units from the levels below, hence, "buddies".
533 * At a high level, all that happens here is marking the table entry
534 * at the bottom level available, and propagating the changes upward
535 * as necessary, plus some accounting needed to play nicely with other
536 * parts of the VM system.
537 * At each level, we keep a list of pages, which are heads of continuous
538 * free pages of length of (1 << order) and marked with _mapcount
539 * PAGE_BUDDY_MAPCOUNT_VALUE. Page's order is recorded in page_private(page)
541 * So when we are allocating or freeing one, we can derive the state of the
542 * other. That is, if we allocate a small block, and both were
543 * free, the remainder of the region must be split into blocks.
544 * If a block is freed, and its buddy is also free, then this
545 * triggers coalescing into a block of larger size.
550 static inline void __free_one_page(struct page
*page
,
551 struct zone
*zone
, unsigned int order
,
554 unsigned long page_idx
;
555 unsigned long combined_idx
;
556 unsigned long uninitialized_var(buddy_idx
);
559 VM_BUG_ON(!zone_is_initialized(zone
));
561 if (unlikely(PageCompound(page
)))
562 if (unlikely(destroy_compound_page(page
, order
)))
565 VM_BUG_ON(migratetype
== -1);
567 page_idx
= page_to_pfn(page
) & ((1 << MAX_ORDER
) - 1);
569 VM_BUG_ON_PAGE(page_idx
& ((1 << order
) - 1), page
);
570 VM_BUG_ON_PAGE(bad_range(zone
, page
), page
);
572 while (order
< MAX_ORDER
-1) {
573 buddy_idx
= __find_buddy_index(page_idx
, order
);
574 buddy
= page
+ (buddy_idx
- page_idx
);
575 if (!page_is_buddy(page
, buddy
, order
))
578 * Our buddy is free or it is CONFIG_DEBUG_PAGEALLOC guard page,
579 * merge with it and move up one order.
581 if (page_is_guard(buddy
)) {
582 clear_page_guard_flag(buddy
);
583 set_page_private(page
, 0);
584 __mod_zone_freepage_state(zone
, 1 << order
,
587 list_del(&buddy
->lru
);
588 zone
->free_area
[order
].nr_free
--;
589 rmv_page_order(buddy
);
591 combined_idx
= buddy_idx
& page_idx
;
592 page
= page
+ (combined_idx
- page_idx
);
593 page_idx
= combined_idx
;
596 set_page_order(page
, order
);
599 * If this is not the largest possible page, check if the buddy
600 * of the next-highest order is free. If it is, it's possible
601 * that pages are being freed that will coalesce soon. In case,
602 * that is happening, add the free page to the tail of the list
603 * so it's less likely to be used soon and more likely to be merged
604 * as a higher order page
606 if ((order
< MAX_ORDER
-2) && pfn_valid_within(page_to_pfn(buddy
))) {
607 struct page
*higher_page
, *higher_buddy
;
608 combined_idx
= buddy_idx
& page_idx
;
609 higher_page
= page
+ (combined_idx
- page_idx
);
610 buddy_idx
= __find_buddy_index(combined_idx
, order
+ 1);
611 higher_buddy
= higher_page
+ (buddy_idx
- combined_idx
);
612 if (page_is_buddy(higher_page
, higher_buddy
, order
+ 1)) {
613 list_add_tail(&page
->lru
,
614 &zone
->free_area
[order
].free_list
[migratetype
]);
619 list_add(&page
->lru
, &zone
->free_area
[order
].free_list
[migratetype
]);
621 zone
->free_area
[order
].nr_free
++;
624 static inline int free_pages_check(struct page
*page
)
626 char *bad_reason
= NULL
;
627 unsigned long bad_flags
= 0;
629 if (unlikely(page_mapcount(page
)))
630 bad_reason
= "nonzero mapcount";
631 if (unlikely(page
->mapping
!= NULL
))
632 bad_reason
= "non-NULL mapping";
633 if (unlikely(atomic_read(&page
->_count
) != 0))
634 bad_reason
= "nonzero _count";
635 if (unlikely(page
->flags
& PAGE_FLAGS_CHECK_AT_FREE
)) {
636 bad_reason
= "PAGE_FLAGS_CHECK_AT_FREE flag(s) set";
637 bad_flags
= PAGE_FLAGS_CHECK_AT_FREE
;
639 if (unlikely(mem_cgroup_bad_page_check(page
)))
640 bad_reason
= "cgroup check failed";
641 if (unlikely(bad_reason
)) {
642 bad_page(page
, bad_reason
, bad_flags
);
645 page_cpupid_reset_last(page
);
646 if (page
->flags
& PAGE_FLAGS_CHECK_AT_PREP
)
647 page
->flags
&= ~PAGE_FLAGS_CHECK_AT_PREP
;
652 * Frees a number of pages from the PCP lists
653 * Assumes all pages on list are in same zone, and of same order.
654 * count is the number of pages to free.
656 * If the zone was previously in an "all pages pinned" state then look to
657 * see if this freeing clears that state.
659 * And clear the zone's pages_scanned counter, to hold off the "all pages are
660 * pinned" detection logic.
662 static void free_pcppages_bulk(struct zone
*zone
, int count
,
663 struct per_cpu_pages
*pcp
)
669 spin_lock(&zone
->lock
);
670 zone
->pages_scanned
= 0;
674 struct list_head
*list
;
677 * Remove pages from lists in a round-robin fashion. A
678 * batch_free count is maintained that is incremented when an
679 * empty list is encountered. This is so more pages are freed
680 * off fuller lists instead of spinning excessively around empty
685 if (++migratetype
== MIGRATE_PCPTYPES
)
687 list
= &pcp
->lists
[migratetype
];
688 } while (list_empty(list
));
690 /* This is the only non-empty list. Free them all. */
691 if (batch_free
== MIGRATE_PCPTYPES
)
692 batch_free
= to_free
;
695 int mt
; /* migratetype of the to-be-freed page */
697 page
= list_entry(list
->prev
, struct page
, lru
);
698 /* must delete as __free_one_page list manipulates */
699 list_del(&page
->lru
);
700 mt
= get_freepage_migratetype(page
);
701 /* MIGRATE_MOVABLE list may include MIGRATE_RESERVEs */
702 __free_one_page(page
, zone
, 0, mt
);
703 trace_mm_page_pcpu_drain(page
, 0, mt
);
704 if (likely(!is_migrate_isolate_page(page
))) {
705 __mod_zone_page_state(zone
, NR_FREE_PAGES
, 1);
706 if (is_migrate_cma(mt
))
707 __mod_zone_page_state(zone
, NR_FREE_CMA_PAGES
, 1);
709 } while (--to_free
&& --batch_free
&& !list_empty(list
));
711 spin_unlock(&zone
->lock
);
714 static void free_one_page(struct zone
*zone
, struct page
*page
, int order
,
717 spin_lock(&zone
->lock
);
718 zone
->pages_scanned
= 0;
720 __free_one_page(page
, zone
, order
, migratetype
);
721 if (unlikely(!is_migrate_isolate(migratetype
)))
722 __mod_zone_freepage_state(zone
, 1 << order
, migratetype
);
723 spin_unlock(&zone
->lock
);
726 static bool free_pages_prepare(struct page
*page
, unsigned int order
)
731 trace_mm_page_free(page
, order
);
732 kmemcheck_free_shadow(page
, order
);
735 page
->mapping
= NULL
;
736 for (i
= 0; i
< (1 << order
); i
++)
737 bad
+= free_pages_check(page
+ i
);
741 if (!PageHighMem(page
)) {
742 debug_check_no_locks_freed(page_address(page
),
744 debug_check_no_obj_freed(page_address(page
),
747 arch_free_page(page
, order
);
748 kernel_map_pages(page
, 1 << order
, 0);
753 static void __free_pages_ok(struct page
*page
, unsigned int order
)
758 if (!free_pages_prepare(page
, order
))
761 local_irq_save(flags
);
762 __count_vm_events(PGFREE
, 1 << order
);
763 migratetype
= get_pageblock_migratetype(page
);
764 set_freepage_migratetype(page
, migratetype
);
765 free_one_page(page_zone(page
), page
, order
, migratetype
);
766 local_irq_restore(flags
);
769 void __init
__free_pages_bootmem(struct page
*page
, unsigned int order
)
771 unsigned int nr_pages
= 1 << order
;
772 struct page
*p
= page
;
776 for (loop
= 0; loop
< (nr_pages
- 1); loop
++, p
++) {
778 __ClearPageReserved(p
);
779 set_page_count(p
, 0);
781 __ClearPageReserved(p
);
782 set_page_count(p
, 0);
784 page_zone(page
)->managed_pages
+= nr_pages
;
785 set_page_refcounted(page
);
786 __free_pages(page
, order
);
790 /* Free whole pageblock and set its migration type to MIGRATE_CMA. */
791 void __init
init_cma_reserved_pageblock(struct page
*page
)
793 unsigned i
= pageblock_nr_pages
;
794 struct page
*p
= page
;
797 __ClearPageReserved(p
);
798 set_page_count(p
, 0);
801 set_page_refcounted(page
);
802 set_pageblock_migratetype(page
, MIGRATE_CMA
);
803 __free_pages(page
, pageblock_order
);
804 adjust_managed_page_count(page
, pageblock_nr_pages
);
809 * The order of subdivision here is critical for the IO subsystem.
810 * Please do not alter this order without good reasons and regression
811 * testing. Specifically, as large blocks of memory are subdivided,
812 * the order in which smaller blocks are delivered depends on the order
813 * they're subdivided in this function. This is the primary factor
814 * influencing the order in which pages are delivered to the IO
815 * subsystem according to empirical testing, and this is also justified
816 * by considering the behavior of a buddy system containing a single
817 * large block of memory acted on by a series of small allocations.
818 * This behavior is a critical factor in sglist merging's success.
822 static inline void expand(struct zone
*zone
, struct page
*page
,
823 int low
, int high
, struct free_area
*area
,
826 unsigned long size
= 1 << high
;
832 VM_BUG_ON_PAGE(bad_range(zone
, &page
[size
]), &page
[size
]);
834 #ifdef CONFIG_DEBUG_PAGEALLOC
835 if (high
< debug_guardpage_minorder()) {
837 * Mark as guard pages (or page), that will allow to
838 * merge back to allocator when buddy will be freed.
839 * Corresponding page table entries will not be touched,
840 * pages will stay not present in virtual address space
842 INIT_LIST_HEAD(&page
[size
].lru
);
843 set_page_guard_flag(&page
[size
]);
844 set_page_private(&page
[size
], high
);
845 /* Guard pages are not available for any usage */
846 __mod_zone_freepage_state(zone
, -(1 << high
),
851 list_add(&page
[size
].lru
, &area
->free_list
[migratetype
]);
853 set_page_order(&page
[size
], high
);
858 * This page is about to be returned from the page allocator
860 static inline int check_new_page(struct page
*page
)
862 char *bad_reason
= NULL
;
863 unsigned long bad_flags
= 0;
865 if (unlikely(page_mapcount(page
)))
866 bad_reason
= "nonzero mapcount";
867 if (unlikely(page
->mapping
!= NULL
))
868 bad_reason
= "non-NULL mapping";
869 if (unlikely(atomic_read(&page
->_count
) != 0))
870 bad_reason
= "nonzero _count";
871 if (unlikely(page
->flags
& PAGE_FLAGS_CHECK_AT_PREP
)) {
872 bad_reason
= "PAGE_FLAGS_CHECK_AT_PREP flag set";
873 bad_flags
= PAGE_FLAGS_CHECK_AT_PREP
;
875 if (unlikely(mem_cgroup_bad_page_check(page
)))
876 bad_reason
= "cgroup check failed";
877 if (unlikely(bad_reason
)) {
878 bad_page(page
, bad_reason
, bad_flags
);
884 static int prep_new_page(struct page
*page
, int order
, gfp_t gfp_flags
)
888 for (i
= 0; i
< (1 << order
); i
++) {
889 struct page
*p
= page
+ i
;
890 if (unlikely(check_new_page(p
)))
894 set_page_private(page
, 0);
895 set_page_refcounted(page
);
897 arch_alloc_page(page
, order
);
898 kernel_map_pages(page
, 1 << order
, 1);
900 if (gfp_flags
& __GFP_ZERO
)
901 prep_zero_page(page
, order
, gfp_flags
);
903 if (order
&& (gfp_flags
& __GFP_COMP
))
904 prep_compound_page(page
, order
);
910 * Go through the free lists for the given migratetype and remove
911 * the smallest available page from the freelists
914 struct page
*__rmqueue_smallest(struct zone
*zone
, unsigned int order
,
917 unsigned int current_order
;
918 struct free_area
*area
;
921 /* Find a page of the appropriate size in the preferred list */
922 for (current_order
= order
; current_order
< MAX_ORDER
; ++current_order
) {
923 area
= &(zone
->free_area
[current_order
]);
924 if (list_empty(&area
->free_list
[migratetype
]))
927 page
= list_entry(area
->free_list
[migratetype
].next
,
929 list_del(&page
->lru
);
930 rmv_page_order(page
);
932 expand(zone
, page
, order
, current_order
, area
, migratetype
);
941 * This array describes the order lists are fallen back to when
942 * the free lists for the desirable migrate type are depleted
944 static int fallbacks
[MIGRATE_TYPES
][4] = {
945 [MIGRATE_UNMOVABLE
] = { MIGRATE_RECLAIMABLE
, MIGRATE_MOVABLE
, MIGRATE_RESERVE
},
946 [MIGRATE_RECLAIMABLE
] = { MIGRATE_UNMOVABLE
, MIGRATE_MOVABLE
, MIGRATE_RESERVE
},
948 [MIGRATE_MOVABLE
] = { MIGRATE_CMA
, MIGRATE_RECLAIMABLE
, MIGRATE_UNMOVABLE
, MIGRATE_RESERVE
},
949 [MIGRATE_CMA
] = { MIGRATE_RESERVE
}, /* Never used */
951 [MIGRATE_MOVABLE
] = { MIGRATE_RECLAIMABLE
, MIGRATE_UNMOVABLE
, MIGRATE_RESERVE
},
953 [MIGRATE_RESERVE
] = { MIGRATE_RESERVE
}, /* Never used */
954 #ifdef CONFIG_MEMORY_ISOLATION
955 [MIGRATE_ISOLATE
] = { MIGRATE_RESERVE
}, /* Never used */
960 * Move the free pages in a range to the free lists of the requested type.
961 * Note that start_page and end_pages are not aligned on a pageblock
962 * boundary. If alignment is required, use move_freepages_block()
964 int move_freepages(struct zone
*zone
,
965 struct page
*start_page
, struct page
*end_page
,
972 #ifndef CONFIG_HOLES_IN_ZONE
974 * page_zone is not safe to call in this context when
975 * CONFIG_HOLES_IN_ZONE is set. This bug check is probably redundant
976 * anyway as we check zone boundaries in move_freepages_block().
977 * Remove at a later date when no bug reports exist related to
978 * grouping pages by mobility
980 BUG_ON(page_zone(start_page
) != page_zone(end_page
));
983 for (page
= start_page
; page
<= end_page
;) {
984 /* Make sure we are not inadvertently changing nodes */
985 VM_BUG_ON_PAGE(page_to_nid(page
) != zone_to_nid(zone
), page
);
987 if (!pfn_valid_within(page_to_pfn(page
))) {
992 if (!PageBuddy(page
)) {
997 order
= page_order(page
);
998 list_move(&page
->lru
,
999 &zone
->free_area
[order
].free_list
[migratetype
]);
1000 set_freepage_migratetype(page
, migratetype
);
1002 pages_moved
+= 1 << order
;
1008 int move_freepages_block(struct zone
*zone
, struct page
*page
,
1011 unsigned long start_pfn
, end_pfn
;
1012 struct page
*start_page
, *end_page
;
1014 start_pfn
= page_to_pfn(page
);
1015 start_pfn
= start_pfn
& ~(pageblock_nr_pages
-1);
1016 start_page
= pfn_to_page(start_pfn
);
1017 end_page
= start_page
+ pageblock_nr_pages
- 1;
1018 end_pfn
= start_pfn
+ pageblock_nr_pages
- 1;
1020 /* Do not cross zone boundaries */
1021 if (!zone_spans_pfn(zone
, start_pfn
))
1023 if (!zone_spans_pfn(zone
, end_pfn
))
1026 return move_freepages(zone
, start_page
, end_page
, migratetype
);
1029 static void change_pageblock_range(struct page
*pageblock_page
,
1030 int start_order
, int migratetype
)
1032 int nr_pageblocks
= 1 << (start_order
- pageblock_order
);
1034 while (nr_pageblocks
--) {
1035 set_pageblock_migratetype(pageblock_page
, migratetype
);
1036 pageblock_page
+= pageblock_nr_pages
;
1041 * If breaking a large block of pages, move all free pages to the preferred
1042 * allocation list. If falling back for a reclaimable kernel allocation, be
1043 * more aggressive about taking ownership of free pages.
1045 * On the other hand, never change migration type of MIGRATE_CMA pageblocks
1046 * nor move CMA pages to different free lists. We don't want unmovable pages
1047 * to be allocated from MIGRATE_CMA areas.
1049 * Returns the new migratetype of the pageblock (or the same old migratetype
1050 * if it was unchanged).
1052 static int try_to_steal_freepages(struct zone
*zone
, struct page
*page
,
1053 int start_type
, int fallback_type
)
1055 int current_order
= page_order(page
);
1058 * When borrowing from MIGRATE_CMA, we need to release the excess
1059 * buddy pages to CMA itself.
1061 if (is_migrate_cma(fallback_type
))
1062 return fallback_type
;
1064 /* Take ownership for orders >= pageblock_order */
1065 if (current_order
>= pageblock_order
) {
1066 change_pageblock_range(page
, current_order
, start_type
);
1070 if (current_order
>= pageblock_order
/ 2 ||
1071 start_type
== MIGRATE_RECLAIMABLE
||
1072 page_group_by_mobility_disabled
) {
1075 pages
= move_freepages_block(zone
, page
, start_type
);
1077 /* Claim the whole block if over half of it is free */
1078 if (pages
>= (1 << (pageblock_order
-1)) ||
1079 page_group_by_mobility_disabled
) {
1081 set_pageblock_migratetype(page
, start_type
);
1087 return fallback_type
;
1090 /* Remove an element from the buddy allocator from the fallback list */
1091 static inline struct page
*
1092 __rmqueue_fallback(struct zone
*zone
, int order
, int start_migratetype
)
1094 struct free_area
*area
;
1097 int migratetype
, new_type
, i
;
1099 /* Find the largest possible block of pages in the other list */
1100 for (current_order
= MAX_ORDER
-1; current_order
>= order
;
1103 migratetype
= fallbacks
[start_migratetype
][i
];
1105 /* MIGRATE_RESERVE handled later if necessary */
1106 if (migratetype
== MIGRATE_RESERVE
)
1109 area
= &(zone
->free_area
[current_order
]);
1110 if (list_empty(&area
->free_list
[migratetype
]))
1113 page
= list_entry(area
->free_list
[migratetype
].next
,
1117 new_type
= try_to_steal_freepages(zone
, page
,
1121 /* Remove the page from the freelists */
1122 list_del(&page
->lru
);
1123 rmv_page_order(page
);
1125 expand(zone
, page
, order
, current_order
, area
,
1128 trace_mm_page_alloc_extfrag(page
, order
, current_order
,
1129 start_migratetype
, migratetype
, new_type
);
1139 * Do the hard work of removing an element from the buddy allocator.
1140 * Call me with the zone->lock already held.
1142 static struct page
*__rmqueue(struct zone
*zone
, unsigned int order
,
1148 page
= __rmqueue_smallest(zone
, order
, migratetype
);
1150 if (unlikely(!page
) && migratetype
!= MIGRATE_RESERVE
) {
1151 page
= __rmqueue_fallback(zone
, order
, migratetype
);
1154 * Use MIGRATE_RESERVE rather than fail an allocation. goto
1155 * is used because __rmqueue_smallest is an inline function
1156 * and we want just one call site
1159 migratetype
= MIGRATE_RESERVE
;
1164 trace_mm_page_alloc_zone_locked(page
, order
, migratetype
);
1169 * Obtain a specified number of elements from the buddy allocator, all under
1170 * a single hold of the lock, for efficiency. Add them to the supplied list.
1171 * Returns the number of new pages which were placed at *list.
1173 static int rmqueue_bulk(struct zone
*zone
, unsigned int order
,
1174 unsigned long count
, struct list_head
*list
,
1175 int migratetype
, int cold
)
1177 int mt
= migratetype
, i
;
1179 spin_lock(&zone
->lock
);
1180 for (i
= 0; i
< count
; ++i
) {
1181 struct page
*page
= __rmqueue(zone
, order
, migratetype
);
1182 if (unlikely(page
== NULL
))
1186 * Split buddy pages returned by expand() are received here
1187 * in physical page order. The page is added to the callers and
1188 * list and the list head then moves forward. From the callers
1189 * perspective, the linked list is ordered by page number in
1190 * some conditions. This is useful for IO devices that can
1191 * merge IO requests if the physical pages are ordered
1194 if (likely(cold
== 0))
1195 list_add(&page
->lru
, list
);
1197 list_add_tail(&page
->lru
, list
);
1198 if (IS_ENABLED(CONFIG_CMA
)) {
1199 mt
= get_pageblock_migratetype(page
);
1200 if (!is_migrate_cma(mt
) && !is_migrate_isolate(mt
))
1203 set_freepage_migratetype(page
, mt
);
1205 if (is_migrate_cma(mt
))
1206 __mod_zone_page_state(zone
, NR_FREE_CMA_PAGES
,
1209 __mod_zone_page_state(zone
, NR_FREE_PAGES
, -(i
<< order
));
1210 spin_unlock(&zone
->lock
);
1216 * Called from the vmstat counter updater to drain pagesets of this
1217 * currently executing processor on remote nodes after they have
1220 * Note that this function must be called with the thread pinned to
1221 * a single processor.
1223 void drain_zone_pages(struct zone
*zone
, struct per_cpu_pages
*pcp
)
1225 unsigned long flags
;
1227 unsigned long batch
;
1229 local_irq_save(flags
);
1230 batch
= ACCESS_ONCE(pcp
->batch
);
1231 if (pcp
->count
>= batch
)
1234 to_drain
= pcp
->count
;
1236 free_pcppages_bulk(zone
, to_drain
, pcp
);
1237 pcp
->count
-= to_drain
;
1239 local_irq_restore(flags
);
1241 static bool gfp_thisnode_allocation(gfp_t gfp_mask
)
1243 return (gfp_mask
& GFP_THISNODE
) == GFP_THISNODE
;
1246 static bool gfp_thisnode_allocation(gfp_t gfp_mask
)
1253 * Drain pages of the indicated processor.
1255 * The processor must either be the current processor and the
1256 * thread pinned to the current processor or a processor that
1259 static void drain_pages(unsigned int cpu
)
1261 unsigned long flags
;
1264 for_each_populated_zone(zone
) {
1265 struct per_cpu_pageset
*pset
;
1266 struct per_cpu_pages
*pcp
;
1268 local_irq_save(flags
);
1269 pset
= per_cpu_ptr(zone
->pageset
, cpu
);
1273 free_pcppages_bulk(zone
, pcp
->count
, pcp
);
1276 local_irq_restore(flags
);
1281 * Spill all of this CPU's per-cpu pages back into the buddy allocator.
1283 void drain_local_pages(void *arg
)
1285 drain_pages(smp_processor_id());
1289 * Spill all the per-cpu pages from all CPUs back into the buddy allocator.
1291 * Note that this code is protected against sending an IPI to an offline
1292 * CPU but does not guarantee sending an IPI to newly hotplugged CPUs:
1293 * on_each_cpu_mask() blocks hotplug and won't talk to offlined CPUs but
1294 * nothing keeps CPUs from showing up after we populated the cpumask and
1295 * before the call to on_each_cpu_mask().
1297 void drain_all_pages(void)
1300 struct per_cpu_pageset
*pcp
;
1304 * Allocate in the BSS so we wont require allocation in
1305 * direct reclaim path for CONFIG_CPUMASK_OFFSTACK=y
1307 static cpumask_t cpus_with_pcps
;
1310 * We don't care about racing with CPU hotplug event
1311 * as offline notification will cause the notified
1312 * cpu to drain that CPU pcps and on_each_cpu_mask
1313 * disables preemption as part of its processing
1315 for_each_online_cpu(cpu
) {
1316 bool has_pcps
= false;
1317 for_each_populated_zone(zone
) {
1318 pcp
= per_cpu_ptr(zone
->pageset
, cpu
);
1319 if (pcp
->pcp
.count
) {
1325 cpumask_set_cpu(cpu
, &cpus_with_pcps
);
1327 cpumask_clear_cpu(cpu
, &cpus_with_pcps
);
1329 on_each_cpu_mask(&cpus_with_pcps
, drain_local_pages
, NULL
, 1);
1332 #ifdef CONFIG_HIBERNATION
1334 void mark_free_pages(struct zone
*zone
)
1336 unsigned long pfn
, max_zone_pfn
;
1337 unsigned long flags
;
1339 struct list_head
*curr
;
1341 if (zone_is_empty(zone
))
1344 spin_lock_irqsave(&zone
->lock
, flags
);
1346 max_zone_pfn
= zone_end_pfn(zone
);
1347 for (pfn
= zone
->zone_start_pfn
; pfn
< max_zone_pfn
; pfn
++)
1348 if (pfn_valid(pfn
)) {
1349 struct page
*page
= pfn_to_page(pfn
);
1351 if (!swsusp_page_is_forbidden(page
))
1352 swsusp_unset_page_free(page
);
1355 for_each_migratetype_order(order
, t
) {
1356 list_for_each(curr
, &zone
->free_area
[order
].free_list
[t
]) {
1359 pfn
= page_to_pfn(list_entry(curr
, struct page
, lru
));
1360 for (i
= 0; i
< (1UL << order
); i
++)
1361 swsusp_set_page_free(pfn_to_page(pfn
+ i
));
1364 spin_unlock_irqrestore(&zone
->lock
, flags
);
1366 #endif /* CONFIG_PM */
1369 * Free a 0-order page
1370 * cold == 1 ? free a cold page : free a hot page
1372 void free_hot_cold_page(struct page
*page
, int cold
)
1374 struct zone
*zone
= page_zone(page
);
1375 struct per_cpu_pages
*pcp
;
1376 unsigned long flags
;
1379 if (!free_pages_prepare(page
, 0))
1382 migratetype
= get_pageblock_migratetype(page
);
1383 set_freepage_migratetype(page
, migratetype
);
1384 local_irq_save(flags
);
1385 __count_vm_event(PGFREE
);
1388 * We only track unmovable, reclaimable and movable on pcp lists.
1389 * Free ISOLATE pages back to the allocator because they are being
1390 * offlined but treat RESERVE as movable pages so we can get those
1391 * areas back if necessary. Otherwise, we may have to free
1392 * excessively into the page allocator
1394 if (migratetype
>= MIGRATE_PCPTYPES
) {
1395 if (unlikely(is_migrate_isolate(migratetype
))) {
1396 free_one_page(zone
, page
, 0, migratetype
);
1399 migratetype
= MIGRATE_MOVABLE
;
1402 pcp
= &this_cpu_ptr(zone
->pageset
)->pcp
;
1404 list_add_tail(&page
->lru
, &pcp
->lists
[migratetype
]);
1406 list_add(&page
->lru
, &pcp
->lists
[migratetype
]);
1408 if (pcp
->count
>= pcp
->high
) {
1409 unsigned long batch
= ACCESS_ONCE(pcp
->batch
);
1410 free_pcppages_bulk(zone
, batch
, pcp
);
1411 pcp
->count
-= batch
;
1415 local_irq_restore(flags
);
1419 * Free a list of 0-order pages
1421 void free_hot_cold_page_list(struct list_head
*list
, int cold
)
1423 struct page
*page
, *next
;
1425 list_for_each_entry_safe(page
, next
, list
, lru
) {
1426 trace_mm_page_free_batched(page
, cold
);
1427 free_hot_cold_page(page
, cold
);
1432 * split_page takes a non-compound higher-order page, and splits it into
1433 * n (1<<order) sub-pages: page[0..n]
1434 * Each sub-page must be freed individually.
1436 * Note: this is probably too low level an operation for use in drivers.
1437 * Please consult with lkml before using this in your driver.
1439 void split_page(struct page
*page
, unsigned int order
)
1443 VM_BUG_ON_PAGE(PageCompound(page
), page
);
1444 VM_BUG_ON_PAGE(!page_count(page
), page
);
1446 #ifdef CONFIG_KMEMCHECK
1448 * Split shadow pages too, because free(page[0]) would
1449 * otherwise free the whole shadow.
1451 if (kmemcheck_page_is_tracked(page
))
1452 split_page(virt_to_page(page
[0].shadow
), order
);
1455 for (i
= 1; i
< (1 << order
); i
++)
1456 set_page_refcounted(page
+ i
);
1458 EXPORT_SYMBOL_GPL(split_page
);
1460 static int __isolate_free_page(struct page
*page
, unsigned int order
)
1462 unsigned long watermark
;
1466 BUG_ON(!PageBuddy(page
));
1468 zone
= page_zone(page
);
1469 mt
= get_pageblock_migratetype(page
);
1471 if (!is_migrate_isolate(mt
)) {
1472 /* Obey watermarks as if the page was being allocated */
1473 watermark
= low_wmark_pages(zone
) + (1 << order
);
1474 if (!zone_watermark_ok(zone
, 0, watermark
, 0, 0))
1477 __mod_zone_freepage_state(zone
, -(1UL << order
), mt
);
1480 /* Remove page from free list */
1481 list_del(&page
->lru
);
1482 zone
->free_area
[order
].nr_free
--;
1483 rmv_page_order(page
);
1485 /* Set the pageblock if the isolated page is at least a pageblock */
1486 if (order
>= pageblock_order
- 1) {
1487 struct page
*endpage
= page
+ (1 << order
) - 1;
1488 for (; page
< endpage
; page
+= pageblock_nr_pages
) {
1489 int mt
= get_pageblock_migratetype(page
);
1490 if (!is_migrate_isolate(mt
) && !is_migrate_cma(mt
))
1491 set_pageblock_migratetype(page
,
1496 return 1UL << order
;
1500 * Similar to split_page except the page is already free. As this is only
1501 * being used for migration, the migratetype of the block also changes.
1502 * As this is called with interrupts disabled, the caller is responsible
1503 * for calling arch_alloc_page() and kernel_map_page() after interrupts
1506 * Note: this is probably too low level an operation for use in drivers.
1507 * Please consult with lkml before using this in your driver.
1509 int split_free_page(struct page
*page
)
1514 order
= page_order(page
);
1516 nr_pages
= __isolate_free_page(page
, order
);
1520 /* Split into individual pages */
1521 set_page_refcounted(page
);
1522 split_page(page
, order
);
1527 * Really, prep_compound_page() should be called from __rmqueue_bulk(). But
1528 * we cheat by calling it from here, in the order > 0 path. Saves a branch
1532 struct page
*buffered_rmqueue(struct zone
*preferred_zone
,
1533 struct zone
*zone
, int order
, gfp_t gfp_flags
,
1536 unsigned long flags
;
1538 int cold
= !!(gfp_flags
& __GFP_COLD
);
1541 if (likely(order
== 0)) {
1542 struct per_cpu_pages
*pcp
;
1543 struct list_head
*list
;
1545 local_irq_save(flags
);
1546 pcp
= &this_cpu_ptr(zone
->pageset
)->pcp
;
1547 list
= &pcp
->lists
[migratetype
];
1548 if (list_empty(list
)) {
1549 pcp
->count
+= rmqueue_bulk(zone
, 0,
1552 if (unlikely(list_empty(list
)))
1557 page
= list_entry(list
->prev
, struct page
, lru
);
1559 page
= list_entry(list
->next
, struct page
, lru
);
1561 list_del(&page
->lru
);
1564 if (unlikely(gfp_flags
& __GFP_NOFAIL
)) {
1566 * __GFP_NOFAIL is not to be used in new code.
1568 * All __GFP_NOFAIL callers should be fixed so that they
1569 * properly detect and handle allocation failures.
1571 * We most definitely don't want callers attempting to
1572 * allocate greater than order-1 page units with
1575 WARN_ON_ONCE(order
> 1);
1577 spin_lock_irqsave(&zone
->lock
, flags
);
1578 page
= __rmqueue(zone
, order
, migratetype
);
1579 spin_unlock(&zone
->lock
);
1582 __mod_zone_freepage_state(zone
, -(1 << order
),
1583 get_pageblock_migratetype(page
));
1587 * NOTE: GFP_THISNODE allocations do not partake in the kswapd
1588 * aging protocol, so they can't be fair.
1590 if (!gfp_thisnode_allocation(gfp_flags
))
1591 __mod_zone_page_state(zone
, NR_ALLOC_BATCH
, -(1 << order
));
1593 __count_zone_vm_events(PGALLOC
, zone
, 1 << order
);
1594 zone_statistics(preferred_zone
, zone
, gfp_flags
);
1595 local_irq_restore(flags
);
1597 VM_BUG_ON_PAGE(bad_range(zone
, page
), page
);
1598 if (prep_new_page(page
, order
, gfp_flags
))
1603 local_irq_restore(flags
);
1607 #ifdef CONFIG_FAIL_PAGE_ALLOC
1610 struct fault_attr attr
;
1612 u32 ignore_gfp_highmem
;
1613 u32 ignore_gfp_wait
;
1615 } fail_page_alloc
= {
1616 .attr
= FAULT_ATTR_INITIALIZER
,
1617 .ignore_gfp_wait
= 1,
1618 .ignore_gfp_highmem
= 1,
1622 static int __init
setup_fail_page_alloc(char *str
)
1624 return setup_fault_attr(&fail_page_alloc
.attr
, str
);
1626 __setup("fail_page_alloc=", setup_fail_page_alloc
);
1628 static bool should_fail_alloc_page(gfp_t gfp_mask
, unsigned int order
)
1630 if (order
< fail_page_alloc
.min_order
)
1632 if (gfp_mask
& __GFP_NOFAIL
)
1634 if (fail_page_alloc
.ignore_gfp_highmem
&& (gfp_mask
& __GFP_HIGHMEM
))
1636 if (fail_page_alloc
.ignore_gfp_wait
&& (gfp_mask
& __GFP_WAIT
))
1639 return should_fail(&fail_page_alloc
.attr
, 1 << order
);
1642 #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
1644 static int __init
fail_page_alloc_debugfs(void)
1646 umode_t mode
= S_IFREG
| S_IRUSR
| S_IWUSR
;
1649 dir
= fault_create_debugfs_attr("fail_page_alloc", NULL
,
1650 &fail_page_alloc
.attr
);
1652 return PTR_ERR(dir
);
1654 if (!debugfs_create_bool("ignore-gfp-wait", mode
, dir
,
1655 &fail_page_alloc
.ignore_gfp_wait
))
1657 if (!debugfs_create_bool("ignore-gfp-highmem", mode
, dir
,
1658 &fail_page_alloc
.ignore_gfp_highmem
))
1660 if (!debugfs_create_u32("min-order", mode
, dir
,
1661 &fail_page_alloc
.min_order
))
1666 debugfs_remove_recursive(dir
);
1671 late_initcall(fail_page_alloc_debugfs
);
1673 #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */
1675 #else /* CONFIG_FAIL_PAGE_ALLOC */
1677 static inline bool should_fail_alloc_page(gfp_t gfp_mask
, unsigned int order
)
1682 #endif /* CONFIG_FAIL_PAGE_ALLOC */
1685 * Return true if free pages are above 'mark'. This takes into account the order
1686 * of the allocation.
1688 static bool __zone_watermark_ok(struct zone
*z
, int order
, unsigned long mark
,
1689 int classzone_idx
, int alloc_flags
, long free_pages
)
1691 /* free_pages my go negative - that's OK */
1693 long lowmem_reserve
= z
->lowmem_reserve
[classzone_idx
];
1697 free_pages
-= (1 << order
) - 1;
1698 if (alloc_flags
& ALLOC_HIGH
)
1700 if (alloc_flags
& ALLOC_HARDER
)
1703 /* If allocation can't use CMA areas don't use free CMA pages */
1704 if (!(alloc_flags
& ALLOC_CMA
))
1705 free_cma
= zone_page_state(z
, NR_FREE_CMA_PAGES
);
1708 if (free_pages
- free_cma
<= min
+ lowmem_reserve
)
1710 for (o
= 0; o
< order
; o
++) {
1711 /* At the next order, this order's pages become unavailable */
1712 free_pages
-= z
->free_area
[o
].nr_free
<< o
;
1714 /* Require fewer higher order pages to be free */
1717 if (free_pages
<= min
)
1723 bool zone_watermark_ok(struct zone
*z
, int order
, unsigned long mark
,
1724 int classzone_idx
, int alloc_flags
)
1726 return __zone_watermark_ok(z
, order
, mark
, classzone_idx
, alloc_flags
,
1727 zone_page_state(z
, NR_FREE_PAGES
));
1730 bool zone_watermark_ok_safe(struct zone
*z
, int order
, unsigned long mark
,
1731 int classzone_idx
, int alloc_flags
)
1733 long free_pages
= zone_page_state(z
, NR_FREE_PAGES
);
1735 if (z
->percpu_drift_mark
&& free_pages
< z
->percpu_drift_mark
)
1736 free_pages
= zone_page_state_snapshot(z
, NR_FREE_PAGES
);
1738 return __zone_watermark_ok(z
, order
, mark
, classzone_idx
, alloc_flags
,
1744 * zlc_setup - Setup for "zonelist cache". Uses cached zone data to
1745 * skip over zones that are not allowed by the cpuset, or that have
1746 * been recently (in last second) found to be nearly full. See further
1747 * comments in mmzone.h. Reduces cache footprint of zonelist scans
1748 * that have to skip over a lot of full or unallowed zones.
1750 * If the zonelist cache is present in the passed zonelist, then
1751 * returns a pointer to the allowed node mask (either the current
1752 * tasks mems_allowed, or node_states[N_MEMORY].)
1754 * If the zonelist cache is not available for this zonelist, does
1755 * nothing and returns NULL.
1757 * If the fullzones BITMAP in the zonelist cache is stale (more than
1758 * a second since last zap'd) then we zap it out (clear its bits.)
1760 * We hold off even calling zlc_setup, until after we've checked the
1761 * first zone in the zonelist, on the theory that most allocations will
1762 * be satisfied from that first zone, so best to examine that zone as
1763 * quickly as we can.
1765 static nodemask_t
*zlc_setup(struct zonelist
*zonelist
, int alloc_flags
)
1767 struct zonelist_cache
*zlc
; /* cached zonelist speedup info */
1768 nodemask_t
*allowednodes
; /* zonelist_cache approximation */
1770 zlc
= zonelist
->zlcache_ptr
;
1774 if (time_after(jiffies
, zlc
->last_full_zap
+ HZ
)) {
1775 bitmap_zero(zlc
->fullzones
, MAX_ZONES_PER_ZONELIST
);
1776 zlc
->last_full_zap
= jiffies
;
1779 allowednodes
= !in_interrupt() && (alloc_flags
& ALLOC_CPUSET
) ?
1780 &cpuset_current_mems_allowed
:
1781 &node_states
[N_MEMORY
];
1782 return allowednodes
;
1786 * Given 'z' scanning a zonelist, run a couple of quick checks to see
1787 * if it is worth looking at further for free memory:
1788 * 1) Check that the zone isn't thought to be full (doesn't have its
1789 * bit set in the zonelist_cache fullzones BITMAP).
1790 * 2) Check that the zones node (obtained from the zonelist_cache
1791 * z_to_n[] mapping) is allowed in the passed in allowednodes mask.
1792 * Return true (non-zero) if zone is worth looking at further, or
1793 * else return false (zero) if it is not.
1795 * This check -ignores- the distinction between various watermarks,
1796 * such as GFP_HIGH, GFP_ATOMIC, PF_MEMALLOC, ... If a zone is
1797 * found to be full for any variation of these watermarks, it will
1798 * be considered full for up to one second by all requests, unless
1799 * we are so low on memory on all allowed nodes that we are forced
1800 * into the second scan of the zonelist.
1802 * In the second scan we ignore this zonelist cache and exactly
1803 * apply the watermarks to all zones, even it is slower to do so.
1804 * We are low on memory in the second scan, and should leave no stone
1805 * unturned looking for a free page.
1807 static int zlc_zone_worth_trying(struct zonelist
*zonelist
, struct zoneref
*z
,
1808 nodemask_t
*allowednodes
)
1810 struct zonelist_cache
*zlc
; /* cached zonelist speedup info */
1811 int i
; /* index of *z in zonelist zones */
1812 int n
; /* node that zone *z is on */
1814 zlc
= zonelist
->zlcache_ptr
;
1818 i
= z
- zonelist
->_zonerefs
;
1821 /* This zone is worth trying if it is allowed but not full */
1822 return node_isset(n
, *allowednodes
) && !test_bit(i
, zlc
->fullzones
);
1826 * Given 'z' scanning a zonelist, set the corresponding bit in
1827 * zlc->fullzones, so that subsequent attempts to allocate a page
1828 * from that zone don't waste time re-examining it.
1830 static void zlc_mark_zone_full(struct zonelist
*zonelist
, struct zoneref
*z
)
1832 struct zonelist_cache
*zlc
; /* cached zonelist speedup info */
1833 int i
; /* index of *z in zonelist zones */
1835 zlc
= zonelist
->zlcache_ptr
;
1839 i
= z
- zonelist
->_zonerefs
;
1841 set_bit(i
, zlc
->fullzones
);
1845 * clear all zones full, called after direct reclaim makes progress so that
1846 * a zone that was recently full is not skipped over for up to a second
1848 static void zlc_clear_zones_full(struct zonelist
*zonelist
)
1850 struct zonelist_cache
*zlc
; /* cached zonelist speedup info */
1852 zlc
= zonelist
->zlcache_ptr
;
1856 bitmap_zero(zlc
->fullzones
, MAX_ZONES_PER_ZONELIST
);
1859 static bool zone_local(struct zone
*local_zone
, struct zone
*zone
)
1861 return local_zone
->node
== zone
->node
;
1864 static bool zone_allows_reclaim(struct zone
*local_zone
, struct zone
*zone
)
1866 return node_isset(local_zone
->node
, zone
->zone_pgdat
->reclaim_nodes
);
1869 static void __paginginit
init_zone_allows_reclaim(int nid
)
1873 for_each_online_node(i
)
1874 if (node_distance(nid
, i
) <= RECLAIM_DISTANCE
)
1875 node_set(i
, NODE_DATA(nid
)->reclaim_nodes
);
1877 zone_reclaim_mode
= 1;
1880 #else /* CONFIG_NUMA */
1882 static nodemask_t
*zlc_setup(struct zonelist
*zonelist
, int alloc_flags
)
1887 static int zlc_zone_worth_trying(struct zonelist
*zonelist
, struct zoneref
*z
,
1888 nodemask_t
*allowednodes
)
1893 static void zlc_mark_zone_full(struct zonelist
*zonelist
, struct zoneref
*z
)
1897 static void zlc_clear_zones_full(struct zonelist
*zonelist
)
1901 static bool zone_local(struct zone
*local_zone
, struct zone
*zone
)
1906 static bool zone_allows_reclaim(struct zone
*local_zone
, struct zone
*zone
)
1911 static inline void init_zone_allows_reclaim(int nid
)
1914 #endif /* CONFIG_NUMA */
1917 * get_page_from_freelist goes through the zonelist trying to allocate
1920 static struct page
*
1921 get_page_from_freelist(gfp_t gfp_mask
, nodemask_t
*nodemask
, unsigned int order
,
1922 struct zonelist
*zonelist
, int high_zoneidx
, int alloc_flags
,
1923 struct zone
*preferred_zone
, int migratetype
)
1926 struct page
*page
= NULL
;
1929 nodemask_t
*allowednodes
= NULL
;/* zonelist_cache approximation */
1930 int zlc_active
= 0; /* set if using zonelist_cache */
1931 int did_zlc_setup
= 0; /* just call zlc_setup() one time */
1933 classzone_idx
= zone_idx(preferred_zone
);
1936 * Scan zonelist, looking for a zone with enough free.
1937 * See also __cpuset_node_allowed_softwall() comment in kernel/cpuset.c.
1939 for_each_zone_zonelist_nodemask(zone
, z
, zonelist
,
1940 high_zoneidx
, nodemask
) {
1943 if (IS_ENABLED(CONFIG_NUMA
) && zlc_active
&&
1944 !zlc_zone_worth_trying(zonelist
, z
, allowednodes
))
1946 if ((alloc_flags
& ALLOC_CPUSET
) &&
1947 !cpuset_zone_allowed_softwall(zone
, gfp_mask
))
1949 BUILD_BUG_ON(ALLOC_NO_WATERMARKS
< NR_WMARK
);
1950 if (unlikely(alloc_flags
& ALLOC_NO_WATERMARKS
))
1953 * Distribute pages in proportion to the individual
1954 * zone size to ensure fair page aging. The zone a
1955 * page was allocated in should have no effect on the
1956 * time the page has in memory before being reclaimed.
1958 * Try to stay in local zones in the fastpath. If
1959 * that fails, the slowpath is entered, which will do
1960 * another pass starting with the local zones, but
1961 * ultimately fall back to remote zones that do not
1962 * partake in the fairness round-robin cycle of this
1965 * NOTE: GFP_THISNODE allocations do not partake in
1966 * the kswapd aging protocol, so they can't be fair.
1968 if ((alloc_flags
& ALLOC_WMARK_LOW
) &&
1969 !gfp_thisnode_allocation(gfp_mask
)) {
1970 if (zone_page_state(zone
, NR_ALLOC_BATCH
) <= 0)
1972 if (!zone_local(preferred_zone
, zone
))
1976 * When allocating a page cache page for writing, we
1977 * want to get it from a zone that is within its dirty
1978 * limit, such that no single zone holds more than its
1979 * proportional share of globally allowed dirty pages.
1980 * The dirty limits take into account the zone's
1981 * lowmem reserves and high watermark so that kswapd
1982 * should be able to balance it without having to
1983 * write pages from its LRU list.
1985 * This may look like it could increase pressure on
1986 * lower zones by failing allocations in higher zones
1987 * before they are full. But the pages that do spill
1988 * over are limited as the lower zones are protected
1989 * by this very same mechanism. It should not become
1990 * a practical burden to them.
1992 * XXX: For now, allow allocations to potentially
1993 * exceed the per-zone dirty limit in the slowpath
1994 * (ALLOC_WMARK_LOW unset) before going into reclaim,
1995 * which is important when on a NUMA setup the allowed
1996 * zones are together not big enough to reach the
1997 * global limit. The proper fix for these situations
1998 * will require awareness of zones in the
1999 * dirty-throttling and the flusher threads.
2001 if ((alloc_flags
& ALLOC_WMARK_LOW
) &&
2002 (gfp_mask
& __GFP_WRITE
) && !zone_dirty_ok(zone
))
2003 goto this_zone_full
;
2005 mark
= zone
->watermark
[alloc_flags
& ALLOC_WMARK_MASK
];
2006 if (!zone_watermark_ok(zone
, order
, mark
,
2007 classzone_idx
, alloc_flags
)) {
2010 if (IS_ENABLED(CONFIG_NUMA
) &&
2011 !did_zlc_setup
&& nr_online_nodes
> 1) {
2013 * we do zlc_setup if there are multiple nodes
2014 * and before considering the first zone allowed
2017 allowednodes
= zlc_setup(zonelist
, alloc_flags
);
2022 if (zone_reclaim_mode
== 0 ||
2023 !zone_allows_reclaim(preferred_zone
, zone
))
2024 goto this_zone_full
;
2027 * As we may have just activated ZLC, check if the first
2028 * eligible zone has failed zone_reclaim recently.
2030 if (IS_ENABLED(CONFIG_NUMA
) && zlc_active
&&
2031 !zlc_zone_worth_trying(zonelist
, z
, allowednodes
))
2034 ret
= zone_reclaim(zone
, gfp_mask
, order
);
2036 case ZONE_RECLAIM_NOSCAN
:
2039 case ZONE_RECLAIM_FULL
:
2040 /* scanned but unreclaimable */
2043 /* did we reclaim enough */
2044 if (zone_watermark_ok(zone
, order
, mark
,
2045 classzone_idx
, alloc_flags
))
2049 * Failed to reclaim enough to meet watermark.
2050 * Only mark the zone full if checking the min
2051 * watermark or if we failed to reclaim just
2052 * 1<<order pages or else the page allocator
2053 * fastpath will prematurely mark zones full
2054 * when the watermark is between the low and
2057 if (((alloc_flags
& ALLOC_WMARK_MASK
) == ALLOC_WMARK_MIN
) ||
2058 ret
== ZONE_RECLAIM_SOME
)
2059 goto this_zone_full
;
2066 page
= buffered_rmqueue(preferred_zone
, zone
, order
,
2067 gfp_mask
, migratetype
);
2071 if (IS_ENABLED(CONFIG_NUMA
))
2072 zlc_mark_zone_full(zonelist
, z
);
2075 if (unlikely(IS_ENABLED(CONFIG_NUMA
) && page
== NULL
&& zlc_active
)) {
2076 /* Disable zlc cache for second zonelist scan */
2083 * page->pfmemalloc is set when ALLOC_NO_WATERMARKS was
2084 * necessary to allocate the page. The expectation is
2085 * that the caller is taking steps that will free more
2086 * memory. The caller should avoid the page being used
2087 * for !PFMEMALLOC purposes.
2089 page
->pfmemalloc
= !!(alloc_flags
& ALLOC_NO_WATERMARKS
);
2095 * Large machines with many possible nodes should not always dump per-node
2096 * meminfo in irq context.
2098 static inline bool should_suppress_show_mem(void)
2103 ret
= in_interrupt();
2108 static DEFINE_RATELIMIT_STATE(nopage_rs
,
2109 DEFAULT_RATELIMIT_INTERVAL
,
2110 DEFAULT_RATELIMIT_BURST
);
2112 void warn_alloc_failed(gfp_t gfp_mask
, int order
, const char *fmt
, ...)
2114 unsigned int filter
= SHOW_MEM_FILTER_NODES
;
2116 if ((gfp_mask
& __GFP_NOWARN
) || !__ratelimit(&nopage_rs
) ||
2117 debug_guardpage_minorder() > 0)
2121 * This documents exceptions given to allocations in certain
2122 * contexts that are allowed to allocate outside current's set
2125 if (!(gfp_mask
& __GFP_NOMEMALLOC
))
2126 if (test_thread_flag(TIF_MEMDIE
) ||
2127 (current
->flags
& (PF_MEMALLOC
| PF_EXITING
)))
2128 filter
&= ~SHOW_MEM_FILTER_NODES
;
2129 if (in_interrupt() || !(gfp_mask
& __GFP_WAIT
))
2130 filter
&= ~SHOW_MEM_FILTER_NODES
;
2133 struct va_format vaf
;
2136 va_start(args
, fmt
);
2141 pr_warn("%pV", &vaf
);
2146 pr_warn("%s: page allocation failure: order:%d, mode:0x%x\n",
2147 current
->comm
, order
, gfp_mask
);
2150 if (!should_suppress_show_mem())
2155 should_alloc_retry(gfp_t gfp_mask
, unsigned int order
,
2156 unsigned long did_some_progress
,
2157 unsigned long pages_reclaimed
)
2159 /* Do not loop if specifically requested */
2160 if (gfp_mask
& __GFP_NORETRY
)
2163 /* Always retry if specifically requested */
2164 if (gfp_mask
& __GFP_NOFAIL
)
2168 * Suspend converts GFP_KERNEL to __GFP_WAIT which can prevent reclaim
2169 * making forward progress without invoking OOM. Suspend also disables
2170 * storage devices so kswapd will not help. Bail if we are suspending.
2172 if (!did_some_progress
&& pm_suspended_storage())
2176 * In this implementation, order <= PAGE_ALLOC_COSTLY_ORDER
2177 * means __GFP_NOFAIL, but that may not be true in other
2180 if (order
<= PAGE_ALLOC_COSTLY_ORDER
)
2184 * For order > PAGE_ALLOC_COSTLY_ORDER, if __GFP_REPEAT is
2185 * specified, then we retry until we no longer reclaim any pages
2186 * (above), or we've reclaimed an order of pages at least as
2187 * large as the allocation's order. In both cases, if the
2188 * allocation still fails, we stop retrying.
2190 if (gfp_mask
& __GFP_REPEAT
&& pages_reclaimed
< (1 << order
))
2196 static inline struct page
*
2197 __alloc_pages_may_oom(gfp_t gfp_mask
, unsigned int order
,
2198 struct zonelist
*zonelist
, enum zone_type high_zoneidx
,
2199 nodemask_t
*nodemask
, struct zone
*preferred_zone
,
2204 /* Acquire the OOM killer lock for the zones in zonelist */
2205 if (!try_set_zonelist_oom(zonelist
, gfp_mask
)) {
2206 schedule_timeout_uninterruptible(1);
2211 * Go through the zonelist yet one more time, keep very high watermark
2212 * here, this is only to catch a parallel oom killing, we must fail if
2213 * we're still under heavy pressure.
2215 page
= get_page_from_freelist(gfp_mask
|__GFP_HARDWALL
, nodemask
,
2216 order
, zonelist
, high_zoneidx
,
2217 ALLOC_WMARK_HIGH
|ALLOC_CPUSET
,
2218 preferred_zone
, migratetype
);
2222 if (!(gfp_mask
& __GFP_NOFAIL
)) {
2223 /* The OOM killer will not help higher order allocs */
2224 if (order
> PAGE_ALLOC_COSTLY_ORDER
)
2226 /* The OOM killer does not needlessly kill tasks for lowmem */
2227 if (high_zoneidx
< ZONE_NORMAL
)
2230 * GFP_THISNODE contains __GFP_NORETRY and we never hit this.
2231 * Sanity check for bare calls of __GFP_THISNODE, not real OOM.
2232 * The caller should handle page allocation failure by itself if
2233 * it specifies __GFP_THISNODE.
2234 * Note: Hugepage uses it but will hit PAGE_ALLOC_COSTLY_ORDER.
2236 if (gfp_mask
& __GFP_THISNODE
)
2239 /* Exhausted what can be done so it's blamo time */
2240 out_of_memory(zonelist
, gfp_mask
, order
, nodemask
, false);
2243 clear_zonelist_oom(zonelist
, gfp_mask
);
2247 #ifdef CONFIG_COMPACTION
2248 /* Try memory compaction for high-order allocations before reclaim */
2249 static struct page
*
2250 __alloc_pages_direct_compact(gfp_t gfp_mask
, unsigned int order
,
2251 struct zonelist
*zonelist
, enum zone_type high_zoneidx
,
2252 nodemask_t
*nodemask
, int alloc_flags
, struct zone
*preferred_zone
,
2253 int migratetype
, bool sync_migration
,
2254 bool *contended_compaction
, bool *deferred_compaction
,
2255 unsigned long *did_some_progress
)
2260 if (compaction_deferred(preferred_zone
, order
)) {
2261 *deferred_compaction
= true;
2265 current
->flags
|= PF_MEMALLOC
;
2266 *did_some_progress
= try_to_compact_pages(zonelist
, order
, gfp_mask
,
2267 nodemask
, sync_migration
,
2268 contended_compaction
);
2269 current
->flags
&= ~PF_MEMALLOC
;
2271 if (*did_some_progress
!= COMPACT_SKIPPED
) {
2274 /* Page migration frees to the PCP lists but we want merging */
2275 drain_pages(get_cpu());
2278 page
= get_page_from_freelist(gfp_mask
, nodemask
,
2279 order
, zonelist
, high_zoneidx
,
2280 alloc_flags
& ~ALLOC_NO_WATERMARKS
,
2281 preferred_zone
, migratetype
);
2283 preferred_zone
->compact_blockskip_flush
= false;
2284 compaction_defer_reset(preferred_zone
, order
, true);
2285 count_vm_event(COMPACTSUCCESS
);
2290 * It's bad if compaction run occurs and fails.
2291 * The most likely reason is that pages exist,
2292 * but not enough to satisfy watermarks.
2294 count_vm_event(COMPACTFAIL
);
2297 * As async compaction considers a subset of pageblocks, only
2298 * defer if the failure was a sync compaction failure.
2301 defer_compaction(preferred_zone
, order
);
2309 static inline struct page
*
2310 __alloc_pages_direct_compact(gfp_t gfp_mask
, unsigned int order
,
2311 struct zonelist
*zonelist
, enum zone_type high_zoneidx
,
2312 nodemask_t
*nodemask
, int alloc_flags
, struct zone
*preferred_zone
,
2313 int migratetype
, bool sync_migration
,
2314 bool *contended_compaction
, bool *deferred_compaction
,
2315 unsigned long *did_some_progress
)
2319 #endif /* CONFIG_COMPACTION */
2321 /* Perform direct synchronous page reclaim */
2323 __perform_reclaim(gfp_t gfp_mask
, unsigned int order
, struct zonelist
*zonelist
,
2324 nodemask_t
*nodemask
)
2326 struct reclaim_state reclaim_state
;
2331 /* We now go into synchronous reclaim */
2332 cpuset_memory_pressure_bump();
2333 current
->flags
|= PF_MEMALLOC
;
2334 lockdep_set_current_reclaim_state(gfp_mask
);
2335 reclaim_state
.reclaimed_slab
= 0;
2336 current
->reclaim_state
= &reclaim_state
;
2338 progress
= try_to_free_pages(zonelist
, order
, gfp_mask
, nodemask
);
2340 current
->reclaim_state
= NULL
;
2341 lockdep_clear_current_reclaim_state();
2342 current
->flags
&= ~PF_MEMALLOC
;
2349 /* The really slow allocator path where we enter direct reclaim */
2350 static inline struct page
*
2351 __alloc_pages_direct_reclaim(gfp_t gfp_mask
, unsigned int order
,
2352 struct zonelist
*zonelist
, enum zone_type high_zoneidx
,
2353 nodemask_t
*nodemask
, int alloc_flags
, struct zone
*preferred_zone
,
2354 int migratetype
, unsigned long *did_some_progress
)
2356 struct page
*page
= NULL
;
2357 bool drained
= false;
2359 *did_some_progress
= __perform_reclaim(gfp_mask
, order
, zonelist
,
2361 if (unlikely(!(*did_some_progress
)))
2364 /* After successful reclaim, reconsider all zones for allocation */
2365 if (IS_ENABLED(CONFIG_NUMA
))
2366 zlc_clear_zones_full(zonelist
);
2369 page
= get_page_from_freelist(gfp_mask
, nodemask
, order
,
2370 zonelist
, high_zoneidx
,
2371 alloc_flags
& ~ALLOC_NO_WATERMARKS
,
2372 preferred_zone
, migratetype
);
2375 * If an allocation failed after direct reclaim, it could be because
2376 * pages are pinned on the per-cpu lists. Drain them and try again
2378 if (!page
&& !drained
) {
2388 * This is called in the allocator slow-path if the allocation request is of
2389 * sufficient urgency to ignore watermarks and take other desperate measures
2391 static inline struct page
*
2392 __alloc_pages_high_priority(gfp_t gfp_mask
, unsigned int order
,
2393 struct zonelist
*zonelist
, enum zone_type high_zoneidx
,
2394 nodemask_t
*nodemask
, struct zone
*preferred_zone
,
2400 page
= get_page_from_freelist(gfp_mask
, nodemask
, order
,
2401 zonelist
, high_zoneidx
, ALLOC_NO_WATERMARKS
,
2402 preferred_zone
, migratetype
);
2404 if (!page
&& gfp_mask
& __GFP_NOFAIL
)
2405 wait_iff_congested(preferred_zone
, BLK_RW_ASYNC
, HZ
/50);
2406 } while (!page
&& (gfp_mask
& __GFP_NOFAIL
));
2411 static void prepare_slowpath(gfp_t gfp_mask
, unsigned int order
,
2412 struct zonelist
*zonelist
,
2413 enum zone_type high_zoneidx
,
2414 struct zone
*preferred_zone
)
2419 for_each_zone_zonelist(zone
, z
, zonelist
, high_zoneidx
) {
2420 if (!(gfp_mask
& __GFP_NO_KSWAPD
))
2421 wakeup_kswapd(zone
, order
, zone_idx(preferred_zone
));
2423 * Only reset the batches of zones that were actually
2424 * considered in the fast path, we don't want to
2425 * thrash fairness information for zones that are not
2426 * actually part of this zonelist's round-robin cycle.
2428 if (!zone_local(preferred_zone
, zone
))
2430 mod_zone_page_state(zone
, NR_ALLOC_BATCH
,
2431 high_wmark_pages(zone
) -
2432 low_wmark_pages(zone
) -
2433 zone_page_state(zone
, NR_ALLOC_BATCH
));
2438 gfp_to_alloc_flags(gfp_t gfp_mask
)
2440 int alloc_flags
= ALLOC_WMARK_MIN
| ALLOC_CPUSET
;
2441 const gfp_t wait
= gfp_mask
& __GFP_WAIT
;
2443 /* __GFP_HIGH is assumed to be the same as ALLOC_HIGH to save a branch. */
2444 BUILD_BUG_ON(__GFP_HIGH
!= (__force gfp_t
) ALLOC_HIGH
);
2447 * The caller may dip into page reserves a bit more if the caller
2448 * cannot run direct reclaim, or if the caller has realtime scheduling
2449 * policy or is asking for __GFP_HIGH memory. GFP_ATOMIC requests will
2450 * set both ALLOC_HARDER (!wait) and ALLOC_HIGH (__GFP_HIGH).
2452 alloc_flags
|= (__force
int) (gfp_mask
& __GFP_HIGH
);
2456 * Not worth trying to allocate harder for
2457 * __GFP_NOMEMALLOC even if it can't schedule.
2459 if (!(gfp_mask
& __GFP_NOMEMALLOC
))
2460 alloc_flags
|= ALLOC_HARDER
;
2462 * Ignore cpuset if GFP_ATOMIC (!wait) rather than fail alloc.
2463 * See also cpuset_zone_allowed() comment in kernel/cpuset.c.
2465 alloc_flags
&= ~ALLOC_CPUSET
;
2466 } else if (unlikely(rt_task(current
)) && !in_interrupt())
2467 alloc_flags
|= ALLOC_HARDER
;
2469 if (likely(!(gfp_mask
& __GFP_NOMEMALLOC
))) {
2470 if (gfp_mask
& __GFP_MEMALLOC
)
2471 alloc_flags
|= ALLOC_NO_WATERMARKS
;
2472 else if (in_serving_softirq() && (current
->flags
& PF_MEMALLOC
))
2473 alloc_flags
|= ALLOC_NO_WATERMARKS
;
2474 else if (!in_interrupt() &&
2475 ((current
->flags
& PF_MEMALLOC
) ||
2476 unlikely(test_thread_flag(TIF_MEMDIE
))))
2477 alloc_flags
|= ALLOC_NO_WATERMARKS
;
2480 if (allocflags_to_migratetype(gfp_mask
) == MIGRATE_MOVABLE
)
2481 alloc_flags
|= ALLOC_CMA
;
2486 bool gfp_pfmemalloc_allowed(gfp_t gfp_mask
)
2488 return !!(gfp_to_alloc_flags(gfp_mask
) & ALLOC_NO_WATERMARKS
);
2491 static inline struct page
*
2492 __alloc_pages_slowpath(gfp_t gfp_mask
, unsigned int order
,
2493 struct zonelist
*zonelist
, enum zone_type high_zoneidx
,
2494 nodemask_t
*nodemask
, struct zone
*preferred_zone
,
2497 const gfp_t wait
= gfp_mask
& __GFP_WAIT
;
2498 struct page
*page
= NULL
;
2500 unsigned long pages_reclaimed
= 0;
2501 unsigned long did_some_progress
;
2502 bool sync_migration
= false;
2503 bool deferred_compaction
= false;
2504 bool contended_compaction
= false;
2507 * In the slowpath, we sanity check order to avoid ever trying to
2508 * reclaim >= MAX_ORDER areas which will never succeed. Callers may
2509 * be using allocators in order of preference for an area that is
2512 if (order
>= MAX_ORDER
) {
2513 WARN_ON_ONCE(!(gfp_mask
& __GFP_NOWARN
));
2518 * GFP_THISNODE (meaning __GFP_THISNODE, __GFP_NORETRY and
2519 * __GFP_NOWARN set) should not cause reclaim since the subsystem
2520 * (f.e. slab) using GFP_THISNODE may choose to trigger reclaim
2521 * using a larger set of nodes after it has established that the
2522 * allowed per node queues are empty and that nodes are
2525 if (gfp_thisnode_allocation(gfp_mask
))
2529 prepare_slowpath(gfp_mask
, order
, zonelist
,
2530 high_zoneidx
, preferred_zone
);
2533 * OK, we're below the kswapd watermark and have kicked background
2534 * reclaim. Now things get more complex, so set up alloc_flags according
2535 * to how we want to proceed.
2537 alloc_flags
= gfp_to_alloc_flags(gfp_mask
);
2540 * Find the true preferred zone if the allocation is unconstrained by
2543 if (!(alloc_flags
& ALLOC_CPUSET
) && !nodemask
)
2544 first_zones_zonelist(zonelist
, high_zoneidx
, NULL
,
2548 /* This is the last chance, in general, before the goto nopage. */
2549 page
= get_page_from_freelist(gfp_mask
, nodemask
, order
, zonelist
,
2550 high_zoneidx
, alloc_flags
& ~ALLOC_NO_WATERMARKS
,
2551 preferred_zone
, migratetype
);
2555 /* Allocate without watermarks if the context allows */
2556 if (alloc_flags
& ALLOC_NO_WATERMARKS
) {
2558 * Ignore mempolicies if ALLOC_NO_WATERMARKS on the grounds
2559 * the allocation is high priority and these type of
2560 * allocations are system rather than user orientated
2562 zonelist
= node_zonelist(numa_node_id(), gfp_mask
);
2564 page
= __alloc_pages_high_priority(gfp_mask
, order
,
2565 zonelist
, high_zoneidx
, nodemask
,
2566 preferred_zone
, migratetype
);
2572 /* Atomic allocations - we can't balance anything */
2575 * All existing users of the deprecated __GFP_NOFAIL are
2576 * blockable, so warn of any new users that actually allow this
2577 * type of allocation to fail.
2579 WARN_ON_ONCE(gfp_mask
& __GFP_NOFAIL
);
2583 /* Avoid recursion of direct reclaim */
2584 if (current
->flags
& PF_MEMALLOC
)
2587 /* Avoid allocations with no watermarks from looping endlessly */
2588 if (test_thread_flag(TIF_MEMDIE
) && !(gfp_mask
& __GFP_NOFAIL
))
2592 * Try direct compaction. The first pass is asynchronous. Subsequent
2593 * attempts after direct reclaim are synchronous
2595 page
= __alloc_pages_direct_compact(gfp_mask
, order
,
2596 zonelist
, high_zoneidx
,
2598 alloc_flags
, preferred_zone
,
2599 migratetype
, sync_migration
,
2600 &contended_compaction
,
2601 &deferred_compaction
,
2602 &did_some_progress
);
2605 sync_migration
= true;
2608 * If compaction is deferred for high-order allocations, it is because
2609 * sync compaction recently failed. In this is the case and the caller
2610 * requested a movable allocation that does not heavily disrupt the
2611 * system then fail the allocation instead of entering direct reclaim.
2613 if ((deferred_compaction
|| contended_compaction
) &&
2614 (gfp_mask
& __GFP_NO_KSWAPD
))
2617 /* Try direct reclaim and then allocating */
2618 page
= __alloc_pages_direct_reclaim(gfp_mask
, order
,
2619 zonelist
, high_zoneidx
,
2621 alloc_flags
, preferred_zone
,
2622 migratetype
, &did_some_progress
);
2627 * If we failed to make any progress reclaiming, then we are
2628 * running out of options and have to consider going OOM
2630 if (!did_some_progress
) {
2631 if (oom_gfp_allowed(gfp_mask
)) {
2632 if (oom_killer_disabled
)
2634 /* Coredumps can quickly deplete all memory reserves */
2635 if ((current
->flags
& PF_DUMPCORE
) &&
2636 !(gfp_mask
& __GFP_NOFAIL
))
2638 page
= __alloc_pages_may_oom(gfp_mask
, order
,
2639 zonelist
, high_zoneidx
,
2640 nodemask
, preferred_zone
,
2645 if (!(gfp_mask
& __GFP_NOFAIL
)) {
2647 * The oom killer is not called for high-order
2648 * allocations that may fail, so if no progress
2649 * is being made, there are no other options and
2650 * retrying is unlikely to help.
2652 if (order
> PAGE_ALLOC_COSTLY_ORDER
)
2655 * The oom killer is not called for lowmem
2656 * allocations to prevent needlessly killing
2659 if (high_zoneidx
< ZONE_NORMAL
)
2667 /* Check if we should retry the allocation */
2668 pages_reclaimed
+= did_some_progress
;
2669 if (should_alloc_retry(gfp_mask
, order
, did_some_progress
,
2671 /* Wait for some write requests to complete then retry */
2672 wait_iff_congested(preferred_zone
, BLK_RW_ASYNC
, HZ
/50);
2676 * High-order allocations do not necessarily loop after
2677 * direct reclaim and reclaim/compaction depends on compaction
2678 * being called after reclaim so call directly if necessary
2680 page
= __alloc_pages_direct_compact(gfp_mask
, order
,
2681 zonelist
, high_zoneidx
,
2683 alloc_flags
, preferred_zone
,
2684 migratetype
, sync_migration
,
2685 &contended_compaction
,
2686 &deferred_compaction
,
2687 &did_some_progress
);
2693 warn_alloc_failed(gfp_mask
, order
, NULL
);
2696 if (kmemcheck_enabled
)
2697 kmemcheck_pagealloc_alloc(page
, order
, gfp_mask
);
2703 * This is the 'heart' of the zoned buddy allocator.
2706 __alloc_pages_nodemask(gfp_t gfp_mask
, unsigned int order
,
2707 struct zonelist
*zonelist
, nodemask_t
*nodemask
)
2709 enum zone_type high_zoneidx
= gfp_zone(gfp_mask
);
2710 struct zone
*preferred_zone
;
2711 struct page
*page
= NULL
;
2712 int migratetype
= allocflags_to_migratetype(gfp_mask
);
2713 unsigned int cpuset_mems_cookie
;
2714 int alloc_flags
= ALLOC_WMARK_LOW
|ALLOC_CPUSET
;
2715 struct mem_cgroup
*memcg
= NULL
;
2717 gfp_mask
&= gfp_allowed_mask
;
2719 lockdep_trace_alloc(gfp_mask
);
2721 might_sleep_if(gfp_mask
& __GFP_WAIT
);
2723 if (should_fail_alloc_page(gfp_mask
, order
))
2727 * Check the zones suitable for the gfp_mask contain at least one
2728 * valid zone. It's possible to have an empty zonelist as a result
2729 * of GFP_THISNODE and a memoryless node
2731 if (unlikely(!zonelist
->_zonerefs
->zone
))
2735 * Will only have any effect when __GFP_KMEMCG is set. This is
2736 * verified in the (always inline) callee
2738 if (!memcg_kmem_newpage_charge(gfp_mask
, &memcg
, order
))
2742 cpuset_mems_cookie
= get_mems_allowed();
2744 /* The preferred zone is used for statistics later */
2745 first_zones_zonelist(zonelist
, high_zoneidx
,
2746 nodemask
? : &cpuset_current_mems_allowed
,
2748 if (!preferred_zone
)
2752 if (allocflags_to_migratetype(gfp_mask
) == MIGRATE_MOVABLE
)
2753 alloc_flags
|= ALLOC_CMA
;
2755 /* First allocation attempt */
2756 page
= get_page_from_freelist(gfp_mask
|__GFP_HARDWALL
, nodemask
, order
,
2757 zonelist
, high_zoneidx
, alloc_flags
,
2758 preferred_zone
, migratetype
);
2759 if (unlikely(!page
)) {
2761 * Runtime PM, block IO and its error handling path
2762 * can deadlock because I/O on the device might not
2765 gfp_mask
= memalloc_noio_flags(gfp_mask
);
2766 page
= __alloc_pages_slowpath(gfp_mask
, order
,
2767 zonelist
, high_zoneidx
, nodemask
,
2768 preferred_zone
, migratetype
);
2771 trace_mm_page_alloc(page
, order
, gfp_mask
, migratetype
);
2775 * When updating a task's mems_allowed, it is possible to race with
2776 * parallel threads in such a way that an allocation can fail while
2777 * the mask is being updated. If a page allocation is about to fail,
2778 * check if the cpuset changed during allocation and if so, retry.
2780 if (unlikely(!put_mems_allowed(cpuset_mems_cookie
) && !page
))
2783 memcg_kmem_commit_charge(page
, memcg
, order
);
2787 EXPORT_SYMBOL(__alloc_pages_nodemask
);
2790 * Common helper functions.
2792 unsigned long __get_free_pages(gfp_t gfp_mask
, unsigned int order
)
2797 * __get_free_pages() returns a 32-bit address, which cannot represent
2800 VM_BUG_ON((gfp_mask
& __GFP_HIGHMEM
) != 0);
2802 page
= alloc_pages(gfp_mask
, order
);
2805 return (unsigned long) page_address(page
);
2807 EXPORT_SYMBOL(__get_free_pages
);
2809 unsigned long get_zeroed_page(gfp_t gfp_mask
)
2811 return __get_free_pages(gfp_mask
| __GFP_ZERO
, 0);
2813 EXPORT_SYMBOL(get_zeroed_page
);
2815 void __free_pages(struct page
*page
, unsigned int order
)
2817 if (put_page_testzero(page
)) {
2819 free_hot_cold_page(page
, 0);
2821 __free_pages_ok(page
, order
);
2825 EXPORT_SYMBOL(__free_pages
);
2827 void free_pages(unsigned long addr
, unsigned int order
)
2830 VM_BUG_ON(!virt_addr_valid((void *)addr
));
2831 __free_pages(virt_to_page((void *)addr
), order
);
2835 EXPORT_SYMBOL(free_pages
);
2838 * __free_memcg_kmem_pages and free_memcg_kmem_pages will free
2839 * pages allocated with __GFP_KMEMCG.
2841 * Those pages are accounted to a particular memcg, embedded in the
2842 * corresponding page_cgroup. To avoid adding a hit in the allocator to search
2843 * for that information only to find out that it is NULL for users who have no
2844 * interest in that whatsoever, we provide these functions.
2846 * The caller knows better which flags it relies on.
2848 void __free_memcg_kmem_pages(struct page
*page
, unsigned int order
)
2850 memcg_kmem_uncharge_pages(page
, order
);
2851 __free_pages(page
, order
);
2854 void free_memcg_kmem_pages(unsigned long addr
, unsigned int order
)
2857 VM_BUG_ON(!virt_addr_valid((void *)addr
));
2858 __free_memcg_kmem_pages(virt_to_page((void *)addr
), order
);
2862 static void *make_alloc_exact(unsigned long addr
, unsigned order
, size_t size
)
2865 unsigned long alloc_end
= addr
+ (PAGE_SIZE
<< order
);
2866 unsigned long used
= addr
+ PAGE_ALIGN(size
);
2868 split_page(virt_to_page((void *)addr
), order
);
2869 while (used
< alloc_end
) {
2874 return (void *)addr
;
2878 * alloc_pages_exact - allocate an exact number physically-contiguous pages.
2879 * @size: the number of bytes to allocate
2880 * @gfp_mask: GFP flags for the allocation
2882 * This function is similar to alloc_pages(), except that it allocates the
2883 * minimum number of pages to satisfy the request. alloc_pages() can only
2884 * allocate memory in power-of-two pages.
2886 * This function is also limited by MAX_ORDER.
2888 * Memory allocated by this function must be released by free_pages_exact().
2890 void *alloc_pages_exact(size_t size
, gfp_t gfp_mask
)
2892 unsigned int order
= get_order(size
);
2895 addr
= __get_free_pages(gfp_mask
, order
);
2896 return make_alloc_exact(addr
, order
, size
);
2898 EXPORT_SYMBOL(alloc_pages_exact
);
2901 * alloc_pages_exact_nid - allocate an exact number of physically-contiguous
2903 * @nid: the preferred node ID where memory should be allocated
2904 * @size: the number of bytes to allocate
2905 * @gfp_mask: GFP flags for the allocation
2907 * Like alloc_pages_exact(), but try to allocate on node nid first before falling
2909 * Note this is not alloc_pages_exact_node() which allocates on a specific node,
2912 void *alloc_pages_exact_nid(int nid
, size_t size
, gfp_t gfp_mask
)
2914 unsigned order
= get_order(size
);
2915 struct page
*p
= alloc_pages_node(nid
, gfp_mask
, order
);
2918 return make_alloc_exact((unsigned long)page_address(p
), order
, size
);
2920 EXPORT_SYMBOL(alloc_pages_exact_nid
);
2923 * free_pages_exact - release memory allocated via alloc_pages_exact()
2924 * @virt: the value returned by alloc_pages_exact.
2925 * @size: size of allocation, same value as passed to alloc_pages_exact().
2927 * Release the memory allocated by a previous call to alloc_pages_exact.
2929 void free_pages_exact(void *virt
, size_t size
)
2931 unsigned long addr
= (unsigned long)virt
;
2932 unsigned long end
= addr
+ PAGE_ALIGN(size
);
2934 while (addr
< end
) {
2939 EXPORT_SYMBOL(free_pages_exact
);
2942 * nr_free_zone_pages - count number of pages beyond high watermark
2943 * @offset: The zone index of the highest zone
2945 * nr_free_zone_pages() counts the number of counts pages which are beyond the
2946 * high watermark within all zones at or below a given zone index. For each
2947 * zone, the number of pages is calculated as:
2948 * managed_pages - high_pages
2950 static unsigned long nr_free_zone_pages(int offset
)
2955 /* Just pick one node, since fallback list is circular */
2956 unsigned long sum
= 0;
2958 struct zonelist
*zonelist
= node_zonelist(numa_node_id(), GFP_KERNEL
);
2960 for_each_zone_zonelist(zone
, z
, zonelist
, offset
) {
2961 unsigned long size
= zone
->managed_pages
;
2962 unsigned long high
= high_wmark_pages(zone
);
2971 * nr_free_buffer_pages - count number of pages beyond high watermark
2973 * nr_free_buffer_pages() counts the number of pages which are beyond the high
2974 * watermark within ZONE_DMA and ZONE_NORMAL.
2976 unsigned long nr_free_buffer_pages(void)
2978 return nr_free_zone_pages(gfp_zone(GFP_USER
));
2980 EXPORT_SYMBOL_GPL(nr_free_buffer_pages
);
2983 * nr_free_pagecache_pages - count number of pages beyond high watermark
2985 * nr_free_pagecache_pages() counts the number of pages which are beyond the
2986 * high watermark within all zones.
2988 unsigned long nr_free_pagecache_pages(void)
2990 return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE
));
2993 static inline void show_node(struct zone
*zone
)
2995 if (IS_ENABLED(CONFIG_NUMA
))
2996 printk("Node %d ", zone_to_nid(zone
));
2999 void si_meminfo(struct sysinfo
*val
)
3001 val
->totalram
= totalram_pages
;
3003 val
->freeram
= global_page_state(NR_FREE_PAGES
);
3004 val
->bufferram
= nr_blockdev_pages();
3005 val
->totalhigh
= totalhigh_pages
;
3006 val
->freehigh
= nr_free_highpages();
3007 val
->mem_unit
= PAGE_SIZE
;
3010 EXPORT_SYMBOL(si_meminfo
);
3013 void si_meminfo_node(struct sysinfo
*val
, int nid
)
3015 int zone_type
; /* needs to be signed */
3016 unsigned long managed_pages
= 0;
3017 pg_data_t
*pgdat
= NODE_DATA(nid
);
3019 for (zone_type
= 0; zone_type
< MAX_NR_ZONES
; zone_type
++)
3020 managed_pages
+= pgdat
->node_zones
[zone_type
].managed_pages
;
3021 val
->totalram
= managed_pages
;
3022 val
->freeram
= node_page_state(nid
, NR_FREE_PAGES
);
3023 #ifdef CONFIG_HIGHMEM
3024 val
->totalhigh
= pgdat
->node_zones
[ZONE_HIGHMEM
].managed_pages
;
3025 val
->freehigh
= zone_page_state(&pgdat
->node_zones
[ZONE_HIGHMEM
],
3031 val
->mem_unit
= PAGE_SIZE
;
3036 * Determine whether the node should be displayed or not, depending on whether
3037 * SHOW_MEM_FILTER_NODES was passed to show_free_areas().
3039 bool skip_free_areas_node(unsigned int flags
, int nid
)
3042 unsigned int cpuset_mems_cookie
;
3044 if (!(flags
& SHOW_MEM_FILTER_NODES
))
3048 cpuset_mems_cookie
= get_mems_allowed();
3049 ret
= !node_isset(nid
, cpuset_current_mems_allowed
);
3050 } while (!put_mems_allowed(cpuset_mems_cookie
));
3055 #define K(x) ((x) << (PAGE_SHIFT-10))
3057 static void show_migration_types(unsigned char type
)
3059 static const char types
[MIGRATE_TYPES
] = {
3060 [MIGRATE_UNMOVABLE
] = 'U',
3061 [MIGRATE_RECLAIMABLE
] = 'E',
3062 [MIGRATE_MOVABLE
] = 'M',
3063 [MIGRATE_RESERVE
] = 'R',
3065 [MIGRATE_CMA
] = 'C',
3067 #ifdef CONFIG_MEMORY_ISOLATION
3068 [MIGRATE_ISOLATE
] = 'I',
3071 char tmp
[MIGRATE_TYPES
+ 1];
3075 for (i
= 0; i
< MIGRATE_TYPES
; i
++) {
3076 if (type
& (1 << i
))
3081 printk("(%s) ", tmp
);
3085 * Show free area list (used inside shift_scroll-lock stuff)
3086 * We also calculate the percentage fragmentation. We do this by counting the
3087 * memory on each free list with the exception of the first item on the list.
3088 * Suppresses nodes that are not allowed by current's cpuset if
3089 * SHOW_MEM_FILTER_NODES is passed.
3091 void show_free_areas(unsigned int filter
)
3096 for_each_populated_zone(zone
) {
3097 if (skip_free_areas_node(filter
, zone_to_nid(zone
)))
3100 printk("%s per-cpu:\n", zone
->name
);
3102 for_each_online_cpu(cpu
) {
3103 struct per_cpu_pageset
*pageset
;
3105 pageset
= per_cpu_ptr(zone
->pageset
, cpu
);
3107 printk("CPU %4d: hi:%5d, btch:%4d usd:%4d\n",
3108 cpu
, pageset
->pcp
.high
,
3109 pageset
->pcp
.batch
, pageset
->pcp
.count
);
3113 printk("active_anon:%lu inactive_anon:%lu isolated_anon:%lu\n"
3114 " active_file:%lu inactive_file:%lu isolated_file:%lu\n"
3116 " dirty:%lu writeback:%lu unstable:%lu\n"
3117 " free:%lu slab_reclaimable:%lu slab_unreclaimable:%lu\n"
3118 " mapped:%lu shmem:%lu pagetables:%lu bounce:%lu\n"
3120 global_page_state(NR_ACTIVE_ANON
),
3121 global_page_state(NR_INACTIVE_ANON
),
3122 global_page_state(NR_ISOLATED_ANON
),
3123 global_page_state(NR_ACTIVE_FILE
),
3124 global_page_state(NR_INACTIVE_FILE
),
3125 global_page_state(NR_ISOLATED_FILE
),
3126 global_page_state(NR_UNEVICTABLE
),
3127 global_page_state(NR_FILE_DIRTY
),
3128 global_page_state(NR_WRITEBACK
),
3129 global_page_state(NR_UNSTABLE_NFS
),
3130 global_page_state(NR_FREE_PAGES
),
3131 global_page_state(NR_SLAB_RECLAIMABLE
),
3132 global_page_state(NR_SLAB_UNRECLAIMABLE
),
3133 global_page_state(NR_FILE_MAPPED
),
3134 global_page_state(NR_SHMEM
),
3135 global_page_state(NR_PAGETABLE
),
3136 global_page_state(NR_BOUNCE
),
3137 global_page_state(NR_FREE_CMA_PAGES
));
3139 for_each_populated_zone(zone
) {
3142 if (skip_free_areas_node(filter
, zone_to_nid(zone
)))
3150 " active_anon:%lukB"
3151 " inactive_anon:%lukB"
3152 " active_file:%lukB"
3153 " inactive_file:%lukB"
3154 " unevictable:%lukB"
3155 " isolated(anon):%lukB"
3156 " isolated(file):%lukB"
3164 " slab_reclaimable:%lukB"
3165 " slab_unreclaimable:%lukB"
3166 " kernel_stack:%lukB"
3171 " writeback_tmp:%lukB"
3172 " pages_scanned:%lu"
3173 " all_unreclaimable? %s"
3176 K(zone_page_state(zone
, NR_FREE_PAGES
)),
3177 K(min_wmark_pages(zone
)),
3178 K(low_wmark_pages(zone
)),
3179 K(high_wmark_pages(zone
)),
3180 K(zone_page_state(zone
, NR_ACTIVE_ANON
)),
3181 K(zone_page_state(zone
, NR_INACTIVE_ANON
)),
3182 K(zone_page_state(zone
, NR_ACTIVE_FILE
)),
3183 K(zone_page_state(zone
, NR_INACTIVE_FILE
)),
3184 K(zone_page_state(zone
, NR_UNEVICTABLE
)),
3185 K(zone_page_state(zone
, NR_ISOLATED_ANON
)),
3186 K(zone_page_state(zone
, NR_ISOLATED_FILE
)),
3187 K(zone
->present_pages
),
3188 K(zone
->managed_pages
),
3189 K(zone_page_state(zone
, NR_MLOCK
)),
3190 K(zone_page_state(zone
, NR_FILE_DIRTY
)),
3191 K(zone_page_state(zone
, NR_WRITEBACK
)),
3192 K(zone_page_state(zone
, NR_FILE_MAPPED
)),
3193 K(zone_page_state(zone
, NR_SHMEM
)),
3194 K(zone_page_state(zone
, NR_SLAB_RECLAIMABLE
)),
3195 K(zone_page_state(zone
, NR_SLAB_UNRECLAIMABLE
)),
3196 zone_page_state(zone
, NR_KERNEL_STACK
) *
3198 K(zone_page_state(zone
, NR_PAGETABLE
)),
3199 K(zone_page_state(zone
, NR_UNSTABLE_NFS
)),
3200 K(zone_page_state(zone
, NR_BOUNCE
)),
3201 K(zone_page_state(zone
, NR_FREE_CMA_PAGES
)),
3202 K(zone_page_state(zone
, NR_WRITEBACK_TEMP
)),
3203 zone
->pages_scanned
,
3204 (!zone_reclaimable(zone
) ? "yes" : "no")
3206 printk("lowmem_reserve[]:");
3207 for (i
= 0; i
< MAX_NR_ZONES
; i
++)
3208 printk(" %lu", zone
->lowmem_reserve
[i
]);
3212 for_each_populated_zone(zone
) {
3213 unsigned long nr
[MAX_ORDER
], flags
, order
, total
= 0;
3214 unsigned char types
[MAX_ORDER
];
3216 if (skip_free_areas_node(filter
, zone_to_nid(zone
)))
3219 printk("%s: ", zone
->name
);
3221 spin_lock_irqsave(&zone
->lock
, flags
);
3222 for (order
= 0; order
< MAX_ORDER
; order
++) {
3223 struct free_area
*area
= &zone
->free_area
[order
];
3226 nr
[order
] = area
->nr_free
;
3227 total
+= nr
[order
] << order
;
3230 for (type
= 0; type
< MIGRATE_TYPES
; type
++) {
3231 if (!list_empty(&area
->free_list
[type
]))
3232 types
[order
] |= 1 << type
;
3235 spin_unlock_irqrestore(&zone
->lock
, flags
);
3236 for (order
= 0; order
< MAX_ORDER
; order
++) {
3237 printk("%lu*%lukB ", nr
[order
], K(1UL) << order
);
3239 show_migration_types(types
[order
]);
3241 printk("= %lukB\n", K(total
));
3244 hugetlb_show_meminfo();
3246 printk("%ld total pagecache pages\n", global_page_state(NR_FILE_PAGES
));
3248 show_swap_cache_info();
3251 static void zoneref_set_zone(struct zone
*zone
, struct zoneref
*zoneref
)
3253 zoneref
->zone
= zone
;
3254 zoneref
->zone_idx
= zone_idx(zone
);
3258 * Builds allocation fallback zone lists.
3260 * Add all populated zones of a node to the zonelist.
3262 static int build_zonelists_node(pg_data_t
*pgdat
, struct zonelist
*zonelist
,
3266 enum zone_type zone_type
= MAX_NR_ZONES
;
3270 zone
= pgdat
->node_zones
+ zone_type
;
3271 if (populated_zone(zone
)) {
3272 zoneref_set_zone(zone
,
3273 &zonelist
->_zonerefs
[nr_zones
++]);
3274 check_highest_zone(zone_type
);
3276 } while (zone_type
);
3284 * 0 = automatic detection of better ordering.
3285 * 1 = order by ([node] distance, -zonetype)
3286 * 2 = order by (-zonetype, [node] distance)
3288 * If not NUMA, ZONELIST_ORDER_ZONE and ZONELIST_ORDER_NODE will create
3289 * the same zonelist. So only NUMA can configure this param.
3291 #define ZONELIST_ORDER_DEFAULT 0
3292 #define ZONELIST_ORDER_NODE 1
3293 #define ZONELIST_ORDER_ZONE 2
3295 /* zonelist order in the kernel.
3296 * set_zonelist_order() will set this to NODE or ZONE.
3298 static int current_zonelist_order
= ZONELIST_ORDER_DEFAULT
;
3299 static char zonelist_order_name
[3][8] = {"Default", "Node", "Zone"};
3303 /* The value user specified ....changed by config */
3304 static int user_zonelist_order
= ZONELIST_ORDER_DEFAULT
;
3305 /* string for sysctl */
3306 #define NUMA_ZONELIST_ORDER_LEN 16
3307 char numa_zonelist_order
[16] = "default";
3310 * interface for configure zonelist ordering.
3311 * command line option "numa_zonelist_order"
3312 * = "[dD]efault - default, automatic configuration.
3313 * = "[nN]ode - order by node locality, then by zone within node
3314 * = "[zZ]one - order by zone, then by locality within zone
3317 static int __parse_numa_zonelist_order(char *s
)
3319 if (*s
== 'd' || *s
== 'D') {
3320 user_zonelist_order
= ZONELIST_ORDER_DEFAULT
;
3321 } else if (*s
== 'n' || *s
== 'N') {
3322 user_zonelist_order
= ZONELIST_ORDER_NODE
;
3323 } else if (*s
== 'z' || *s
== 'Z') {
3324 user_zonelist_order
= ZONELIST_ORDER_ZONE
;
3327 "Ignoring invalid numa_zonelist_order value: "
3334 static __init
int setup_numa_zonelist_order(char *s
)
3341 ret
= __parse_numa_zonelist_order(s
);
3343 strlcpy(numa_zonelist_order
, s
, NUMA_ZONELIST_ORDER_LEN
);
3347 early_param("numa_zonelist_order", setup_numa_zonelist_order
);
3350 * sysctl handler for numa_zonelist_order
3352 int numa_zonelist_order_handler(ctl_table
*table
, int write
,
3353 void __user
*buffer
, size_t *length
,
3356 char saved_string
[NUMA_ZONELIST_ORDER_LEN
];
3358 static DEFINE_MUTEX(zl_order_mutex
);
3360 mutex_lock(&zl_order_mutex
);
3362 if (strlen((char *)table
->data
) >= NUMA_ZONELIST_ORDER_LEN
) {
3366 strcpy(saved_string
, (char *)table
->data
);
3368 ret
= proc_dostring(table
, write
, buffer
, length
, ppos
);
3372 int oldval
= user_zonelist_order
;
3374 ret
= __parse_numa_zonelist_order((char *)table
->data
);
3377 * bogus value. restore saved string
3379 strncpy((char *)table
->data
, saved_string
,
3380 NUMA_ZONELIST_ORDER_LEN
);
3381 user_zonelist_order
= oldval
;
3382 } else if (oldval
!= user_zonelist_order
) {
3383 mutex_lock(&zonelists_mutex
);
3384 build_all_zonelists(NULL
, NULL
);
3385 mutex_unlock(&zonelists_mutex
);
3389 mutex_unlock(&zl_order_mutex
);
3394 #define MAX_NODE_LOAD (nr_online_nodes)
3395 static int node_load
[MAX_NUMNODES
];
3398 * find_next_best_node - find the next node that should appear in a given node's fallback list
3399 * @node: node whose fallback list we're appending
3400 * @used_node_mask: nodemask_t of already used nodes
3402 * We use a number of factors to determine which is the next node that should
3403 * appear on a given node's fallback list. The node should not have appeared
3404 * already in @node's fallback list, and it should be the next closest node
3405 * according to the distance array (which contains arbitrary distance values
3406 * from each node to each node in the system), and should also prefer nodes
3407 * with no CPUs, since presumably they'll have very little allocation pressure
3408 * on them otherwise.
3409 * It returns -1 if no node is found.
3411 static int find_next_best_node(int node
, nodemask_t
*used_node_mask
)
3414 int min_val
= INT_MAX
;
3415 int best_node
= NUMA_NO_NODE
;
3416 const struct cpumask
*tmp
= cpumask_of_node(0);
3418 /* Use the local node if we haven't already */
3419 if (!node_isset(node
, *used_node_mask
)) {
3420 node_set(node
, *used_node_mask
);
3424 for_each_node_state(n
, N_MEMORY
) {
3426 /* Don't want a node to appear more than once */
3427 if (node_isset(n
, *used_node_mask
))
3430 /* Use the distance array to find the distance */
3431 val
= node_distance(node
, n
);
3433 /* Penalize nodes under us ("prefer the next node") */
3436 /* Give preference to headless and unused nodes */
3437 tmp
= cpumask_of_node(n
);
3438 if (!cpumask_empty(tmp
))
3439 val
+= PENALTY_FOR_NODE_WITH_CPUS
;
3441 /* Slight preference for less loaded node */
3442 val
*= (MAX_NODE_LOAD
*MAX_NUMNODES
);
3443 val
+= node_load
[n
];
3445 if (val
< min_val
) {
3452 node_set(best_node
, *used_node_mask
);
3459 * Build zonelists ordered by node and zones within node.
3460 * This results in maximum locality--normal zone overflows into local
3461 * DMA zone, if any--but risks exhausting DMA zone.
3463 static void build_zonelists_in_node_order(pg_data_t
*pgdat
, int node
)
3466 struct zonelist
*zonelist
;
3468 zonelist
= &pgdat
->node_zonelists
[0];
3469 for (j
= 0; zonelist
->_zonerefs
[j
].zone
!= NULL
; j
++)
3471 j
= build_zonelists_node(NODE_DATA(node
), zonelist
, j
);
3472 zonelist
->_zonerefs
[j
].zone
= NULL
;
3473 zonelist
->_zonerefs
[j
].zone_idx
= 0;
3477 * Build gfp_thisnode zonelists
3479 static void build_thisnode_zonelists(pg_data_t
*pgdat
)
3482 struct zonelist
*zonelist
;
3484 zonelist
= &pgdat
->node_zonelists
[1];
3485 j
= build_zonelists_node(pgdat
, zonelist
, 0);
3486 zonelist
->_zonerefs
[j
].zone
= NULL
;
3487 zonelist
->_zonerefs
[j
].zone_idx
= 0;
3491 * Build zonelists ordered by zone and nodes within zones.
3492 * This results in conserving DMA zone[s] until all Normal memory is
3493 * exhausted, but results in overflowing to remote node while memory
3494 * may still exist in local DMA zone.
3496 static int node_order
[MAX_NUMNODES
];
3498 static void build_zonelists_in_zone_order(pg_data_t
*pgdat
, int nr_nodes
)
3501 int zone_type
; /* needs to be signed */
3503 struct zonelist
*zonelist
;
3505 zonelist
= &pgdat
->node_zonelists
[0];
3507 for (zone_type
= MAX_NR_ZONES
- 1; zone_type
>= 0; zone_type
--) {
3508 for (j
= 0; j
< nr_nodes
; j
++) {
3509 node
= node_order
[j
];
3510 z
= &NODE_DATA(node
)->node_zones
[zone_type
];
3511 if (populated_zone(z
)) {
3513 &zonelist
->_zonerefs
[pos
++]);
3514 check_highest_zone(zone_type
);
3518 zonelist
->_zonerefs
[pos
].zone
= NULL
;
3519 zonelist
->_zonerefs
[pos
].zone_idx
= 0;
3522 static int default_zonelist_order(void)
3525 unsigned long low_kmem_size
, total_size
;
3529 * ZONE_DMA and ZONE_DMA32 can be very small area in the system.
3530 * If they are really small and used heavily, the system can fall
3531 * into OOM very easily.
3532 * This function detect ZONE_DMA/DMA32 size and configures zone order.
3534 /* Is there ZONE_NORMAL ? (ex. ppc has only DMA zone..) */
3537 for_each_online_node(nid
) {
3538 for (zone_type
= 0; zone_type
< MAX_NR_ZONES
; zone_type
++) {
3539 z
= &NODE_DATA(nid
)->node_zones
[zone_type
];
3540 if (populated_zone(z
)) {
3541 if (zone_type
< ZONE_NORMAL
)
3542 low_kmem_size
+= z
->managed_pages
;
3543 total_size
+= z
->managed_pages
;
3544 } else if (zone_type
== ZONE_NORMAL
) {
3546 * If any node has only lowmem, then node order
3547 * is preferred to allow kernel allocations
3548 * locally; otherwise, they can easily infringe
3549 * on other nodes when there is an abundance of
3550 * lowmem available to allocate from.
3552 return ZONELIST_ORDER_NODE
;
3556 if (!low_kmem_size
|| /* there are no DMA area. */
3557 low_kmem_size
> total_size
/2) /* DMA/DMA32 is big. */
3558 return ZONELIST_ORDER_NODE
;
3560 * look into each node's config.
3561 * If there is a node whose DMA/DMA32 memory is very big area on
3562 * local memory, NODE_ORDER may be suitable.
3564 average_size
= total_size
/
3565 (nodes_weight(node_states
[N_MEMORY
]) + 1);
3566 for_each_online_node(nid
) {
3569 for (zone_type
= 0; zone_type
< MAX_NR_ZONES
; zone_type
++) {
3570 z
= &NODE_DATA(nid
)->node_zones
[zone_type
];
3571 if (populated_zone(z
)) {
3572 if (zone_type
< ZONE_NORMAL
)
3573 low_kmem_size
+= z
->present_pages
;
3574 total_size
+= z
->present_pages
;
3577 if (low_kmem_size
&&
3578 total_size
> average_size
&& /* ignore small node */
3579 low_kmem_size
> total_size
* 70/100)
3580 return ZONELIST_ORDER_NODE
;
3582 return ZONELIST_ORDER_ZONE
;
3585 static void set_zonelist_order(void)
3587 if (user_zonelist_order
== ZONELIST_ORDER_DEFAULT
)
3588 current_zonelist_order
= default_zonelist_order();
3590 current_zonelist_order
= user_zonelist_order
;
3593 static void build_zonelists(pg_data_t
*pgdat
)
3597 nodemask_t used_mask
;
3598 int local_node
, prev_node
;
3599 struct zonelist
*zonelist
;
3600 int order
= current_zonelist_order
;
3602 /* initialize zonelists */
3603 for (i
= 0; i
< MAX_ZONELISTS
; i
++) {
3604 zonelist
= pgdat
->node_zonelists
+ i
;
3605 zonelist
->_zonerefs
[0].zone
= NULL
;
3606 zonelist
->_zonerefs
[0].zone_idx
= 0;
3609 /* NUMA-aware ordering of nodes */
3610 local_node
= pgdat
->node_id
;
3611 load
= nr_online_nodes
;
3612 prev_node
= local_node
;
3613 nodes_clear(used_mask
);
3615 memset(node_order
, 0, sizeof(node_order
));
3618 while ((node
= find_next_best_node(local_node
, &used_mask
)) >= 0) {
3620 * We don't want to pressure a particular node.
3621 * So adding penalty to the first node in same
3622 * distance group to make it round-robin.
3624 if (node_distance(local_node
, node
) !=
3625 node_distance(local_node
, prev_node
))
3626 node_load
[node
] = load
;
3630 if (order
== ZONELIST_ORDER_NODE
)
3631 build_zonelists_in_node_order(pgdat
, node
);
3633 node_order
[j
++] = node
; /* remember order */
3636 if (order
== ZONELIST_ORDER_ZONE
) {
3637 /* calculate node order -- i.e., DMA last! */
3638 build_zonelists_in_zone_order(pgdat
, j
);
3641 build_thisnode_zonelists(pgdat
);
3644 /* Construct the zonelist performance cache - see further mmzone.h */
3645 static void build_zonelist_cache(pg_data_t
*pgdat
)
3647 struct zonelist
*zonelist
;
3648 struct zonelist_cache
*zlc
;
3651 zonelist
= &pgdat
->node_zonelists
[0];
3652 zonelist
->zlcache_ptr
= zlc
= &zonelist
->zlcache
;
3653 bitmap_zero(zlc
->fullzones
, MAX_ZONES_PER_ZONELIST
);
3654 for (z
= zonelist
->_zonerefs
; z
->zone
; z
++)
3655 zlc
->z_to_n
[z
- zonelist
->_zonerefs
] = zonelist_node_idx(z
);
3658 #ifdef CONFIG_HAVE_MEMORYLESS_NODES
3660 * Return node id of node used for "local" allocations.
3661 * I.e., first node id of first zone in arg node's generic zonelist.
3662 * Used for initializing percpu 'numa_mem', which is used primarily
3663 * for kernel allocations, so use GFP_KERNEL flags to locate zonelist.
3665 int local_memory_node(int node
)
3669 (void)first_zones_zonelist(node_zonelist(node
, GFP_KERNEL
),
3670 gfp_zone(GFP_KERNEL
),
3677 #else /* CONFIG_NUMA */
3679 static void set_zonelist_order(void)
3681 current_zonelist_order
= ZONELIST_ORDER_ZONE
;
3684 static void build_zonelists(pg_data_t
*pgdat
)
3686 int node
, local_node
;
3688 struct zonelist
*zonelist
;
3690 local_node
= pgdat
->node_id
;
3692 zonelist
= &pgdat
->node_zonelists
[0];
3693 j
= build_zonelists_node(pgdat
, zonelist
, 0);
3696 * Now we build the zonelist so that it contains the zones
3697 * of all the other nodes.
3698 * We don't want to pressure a particular node, so when
3699 * building the zones for node N, we make sure that the
3700 * zones coming right after the local ones are those from
3701 * node N+1 (modulo N)
3703 for (node
= local_node
+ 1; node
< MAX_NUMNODES
; node
++) {
3704 if (!node_online(node
))
3706 j
= build_zonelists_node(NODE_DATA(node
), zonelist
, j
);
3708 for (node
= 0; node
< local_node
; node
++) {
3709 if (!node_online(node
))
3711 j
= build_zonelists_node(NODE_DATA(node
), zonelist
, j
);
3714 zonelist
->_zonerefs
[j
].zone
= NULL
;
3715 zonelist
->_zonerefs
[j
].zone_idx
= 0;
3718 /* non-NUMA variant of zonelist performance cache - just NULL zlcache_ptr */
3719 static void build_zonelist_cache(pg_data_t
*pgdat
)
3721 pgdat
->node_zonelists
[0].zlcache_ptr
= NULL
;
3724 #endif /* CONFIG_NUMA */
3727 * Boot pageset table. One per cpu which is going to be used for all
3728 * zones and all nodes. The parameters will be set in such a way
3729 * that an item put on a list will immediately be handed over to
3730 * the buddy list. This is safe since pageset manipulation is done
3731 * with interrupts disabled.
3733 * The boot_pagesets must be kept even after bootup is complete for
3734 * unused processors and/or zones. They do play a role for bootstrapping
3735 * hotplugged processors.
3737 * zoneinfo_show() and maybe other functions do
3738 * not check if the processor is online before following the pageset pointer.
3739 * Other parts of the kernel may not check if the zone is available.
3741 static void setup_pageset(struct per_cpu_pageset
*p
, unsigned long batch
);
3742 static DEFINE_PER_CPU(struct per_cpu_pageset
, boot_pageset
);
3743 static void setup_zone_pageset(struct zone
*zone
);
3746 * Global mutex to protect against size modification of zonelists
3747 * as well as to serialize pageset setup for the new populated zone.
3749 DEFINE_MUTEX(zonelists_mutex
);
3751 /* return values int ....just for stop_machine() */
3752 static int __build_all_zonelists(void *data
)
3756 pg_data_t
*self
= data
;
3759 memset(node_load
, 0, sizeof(node_load
));
3762 if (self
&& !node_online(self
->node_id
)) {
3763 build_zonelists(self
);
3764 build_zonelist_cache(self
);
3767 for_each_online_node(nid
) {
3768 pg_data_t
*pgdat
= NODE_DATA(nid
);
3770 build_zonelists(pgdat
);
3771 build_zonelist_cache(pgdat
);
3775 * Initialize the boot_pagesets that are going to be used
3776 * for bootstrapping processors. The real pagesets for
3777 * each zone will be allocated later when the per cpu
3778 * allocator is available.
3780 * boot_pagesets are used also for bootstrapping offline
3781 * cpus if the system is already booted because the pagesets
3782 * are needed to initialize allocators on a specific cpu too.
3783 * F.e. the percpu allocator needs the page allocator which
3784 * needs the percpu allocator in order to allocate its pagesets
3785 * (a chicken-egg dilemma).
3787 for_each_possible_cpu(cpu
) {
3788 setup_pageset(&per_cpu(boot_pageset
, cpu
), 0);
3790 #ifdef CONFIG_HAVE_MEMORYLESS_NODES
3792 * We now know the "local memory node" for each node--
3793 * i.e., the node of the first zone in the generic zonelist.
3794 * Set up numa_mem percpu variable for on-line cpus. During
3795 * boot, only the boot cpu should be on-line; we'll init the
3796 * secondary cpus' numa_mem as they come on-line. During
3797 * node/memory hotplug, we'll fixup all on-line cpus.
3799 if (cpu_online(cpu
))
3800 set_cpu_numa_mem(cpu
, local_memory_node(cpu_to_node(cpu
)));
3808 * Called with zonelists_mutex held always
3809 * unless system_state == SYSTEM_BOOTING.
3811 void __ref
build_all_zonelists(pg_data_t
*pgdat
, struct zone
*zone
)
3813 set_zonelist_order();
3815 if (system_state
== SYSTEM_BOOTING
) {
3816 __build_all_zonelists(NULL
);
3817 mminit_verify_zonelist();
3818 cpuset_init_current_mems_allowed();
3820 #ifdef CONFIG_MEMORY_HOTPLUG
3822 setup_zone_pageset(zone
);
3824 /* we have to stop all cpus to guarantee there is no user
3826 stop_machine(__build_all_zonelists
, pgdat
, NULL
);
3827 /* cpuset refresh routine should be here */
3829 vm_total_pages
= nr_free_pagecache_pages();
3831 * Disable grouping by mobility if the number of pages in the
3832 * system is too low to allow the mechanism to work. It would be
3833 * more accurate, but expensive to check per-zone. This check is
3834 * made on memory-hotadd so a system can start with mobility
3835 * disabled and enable it later
3837 if (vm_total_pages
< (pageblock_nr_pages
* MIGRATE_TYPES
))
3838 page_group_by_mobility_disabled
= 1;
3840 page_group_by_mobility_disabled
= 0;
3842 printk("Built %i zonelists in %s order, mobility grouping %s. "
3843 "Total pages: %ld\n",
3845 zonelist_order_name
[current_zonelist_order
],
3846 page_group_by_mobility_disabled
? "off" : "on",
3849 printk("Policy zone: %s\n", zone_names
[policy_zone
]);
3854 * Helper functions to size the waitqueue hash table.
3855 * Essentially these want to choose hash table sizes sufficiently
3856 * large so that collisions trying to wait on pages are rare.
3857 * But in fact, the number of active page waitqueues on typical
3858 * systems is ridiculously low, less than 200. So this is even
3859 * conservative, even though it seems large.
3861 * The constant PAGES_PER_WAITQUEUE specifies the ratio of pages to
3862 * waitqueues, i.e. the size of the waitq table given the number of pages.
3864 #define PAGES_PER_WAITQUEUE 256
3866 #ifndef CONFIG_MEMORY_HOTPLUG
3867 static inline unsigned long wait_table_hash_nr_entries(unsigned long pages
)
3869 unsigned long size
= 1;
3871 pages
/= PAGES_PER_WAITQUEUE
;
3873 while (size
< pages
)
3877 * Once we have dozens or even hundreds of threads sleeping
3878 * on IO we've got bigger problems than wait queue collision.
3879 * Limit the size of the wait table to a reasonable size.
3881 size
= min(size
, 4096UL);
3883 return max(size
, 4UL);
3887 * A zone's size might be changed by hot-add, so it is not possible to determine
3888 * a suitable size for its wait_table. So we use the maximum size now.
3890 * The max wait table size = 4096 x sizeof(wait_queue_head_t). ie:
3892 * i386 (preemption config) : 4096 x 16 = 64Kbyte.
3893 * ia64, x86-64 (no preemption): 4096 x 20 = 80Kbyte.
3894 * ia64, x86-64 (preemption) : 4096 x 24 = 96Kbyte.
3896 * The maximum entries are prepared when a zone's memory is (512K + 256) pages
3897 * or more by the traditional way. (See above). It equals:
3899 * i386, x86-64, powerpc(4K page size) : = ( 2G + 1M)byte.
3900 * ia64(16K page size) : = ( 8G + 4M)byte.
3901 * powerpc (64K page size) : = (32G +16M)byte.
3903 static inline unsigned long wait_table_hash_nr_entries(unsigned long pages
)
3910 * This is an integer logarithm so that shifts can be used later
3911 * to extract the more random high bits from the multiplicative
3912 * hash function before the remainder is taken.
3914 static inline unsigned long wait_table_bits(unsigned long size
)
3920 * Check if a pageblock contains reserved pages
3922 static int pageblock_is_reserved(unsigned long start_pfn
, unsigned long end_pfn
)
3926 for (pfn
= start_pfn
; pfn
< end_pfn
; pfn
++) {
3927 if (!pfn_valid_within(pfn
) || PageReserved(pfn_to_page(pfn
)))
3934 * Mark a number of pageblocks as MIGRATE_RESERVE. The number
3935 * of blocks reserved is based on min_wmark_pages(zone). The memory within
3936 * the reserve will tend to store contiguous free pages. Setting min_free_kbytes
3937 * higher will lead to a bigger reserve which will get freed as contiguous
3938 * blocks as reclaim kicks in
3940 static void setup_zone_migrate_reserve(struct zone
*zone
)
3942 unsigned long start_pfn
, pfn
, end_pfn
, block_end_pfn
;
3944 unsigned long block_migratetype
;
3949 * Get the start pfn, end pfn and the number of blocks to reserve
3950 * We have to be careful to be aligned to pageblock_nr_pages to
3951 * make sure that we always check pfn_valid for the first page in
3954 start_pfn
= zone
->zone_start_pfn
;
3955 end_pfn
= zone_end_pfn(zone
);
3956 start_pfn
= roundup(start_pfn
, pageblock_nr_pages
);
3957 reserve
= roundup(min_wmark_pages(zone
), pageblock_nr_pages
) >>
3961 * Reserve blocks are generally in place to help high-order atomic
3962 * allocations that are short-lived. A min_free_kbytes value that
3963 * would result in more than 2 reserve blocks for atomic allocations
3964 * is assumed to be in place to help anti-fragmentation for the
3965 * future allocation of hugepages at runtime.
3967 reserve
= min(2, reserve
);
3968 old_reserve
= zone
->nr_migrate_reserve_block
;
3970 /* When memory hot-add, we almost always need to do nothing */
3971 if (reserve
== old_reserve
)
3973 zone
->nr_migrate_reserve_block
= reserve
;
3975 for (pfn
= start_pfn
; pfn
< end_pfn
; pfn
+= pageblock_nr_pages
) {
3976 if (!pfn_valid(pfn
))
3978 page
= pfn_to_page(pfn
);
3980 /* Watch out for overlapping nodes */
3981 if (page_to_nid(page
) != zone_to_nid(zone
))
3984 block_migratetype
= get_pageblock_migratetype(page
);
3986 /* Only test what is necessary when the reserves are not met */
3989 * Blocks with reserved pages will never free, skip
3992 block_end_pfn
= min(pfn
+ pageblock_nr_pages
, end_pfn
);
3993 if (pageblock_is_reserved(pfn
, block_end_pfn
))
3996 /* If this block is reserved, account for it */
3997 if (block_migratetype
== MIGRATE_RESERVE
) {
4002 /* Suitable for reserving if this block is movable */
4003 if (block_migratetype
== MIGRATE_MOVABLE
) {
4004 set_pageblock_migratetype(page
,
4006 move_freepages_block(zone
, page
,
4011 } else if (!old_reserve
) {
4013 * At boot time we don't need to scan the whole zone
4014 * for turning off MIGRATE_RESERVE.
4020 * If the reserve is met and this is a previous reserved block,
4023 if (block_migratetype
== MIGRATE_RESERVE
) {
4024 set_pageblock_migratetype(page
, MIGRATE_MOVABLE
);
4025 move_freepages_block(zone
, page
, MIGRATE_MOVABLE
);
4031 * Initially all pages are reserved - free ones are freed
4032 * up by free_all_bootmem() once the early boot process is
4033 * done. Non-atomic initialization, single-pass.
4035 void __meminit
memmap_init_zone(unsigned long size
, int nid
, unsigned long zone
,
4036 unsigned long start_pfn
, enum memmap_context context
)
4039 unsigned long end_pfn
= start_pfn
+ size
;
4043 if (highest_memmap_pfn
< end_pfn
- 1)
4044 highest_memmap_pfn
= end_pfn
- 1;
4046 z
= &NODE_DATA(nid
)->node_zones
[zone
];
4047 for (pfn
= start_pfn
; pfn
< end_pfn
; pfn
++) {
4049 * There can be holes in boot-time mem_map[]s
4050 * handed to this function. They do not
4051 * exist on hotplugged memory.
4053 if (context
== MEMMAP_EARLY
) {
4054 if (!early_pfn_valid(pfn
))
4056 if (!early_pfn_in_nid(pfn
, nid
))
4059 page
= pfn_to_page(pfn
);
4060 set_page_links(page
, zone
, nid
, pfn
);
4061 mminit_verify_page_links(page
, zone
, nid
, pfn
);
4062 init_page_count(page
);
4063 page_mapcount_reset(page
);
4064 page_cpupid_reset_last(page
);
4065 SetPageReserved(page
);
4067 * Mark the block movable so that blocks are reserved for
4068 * movable at startup. This will force kernel allocations
4069 * to reserve their blocks rather than leaking throughout
4070 * the address space during boot when many long-lived
4071 * kernel allocations are made. Later some blocks near
4072 * the start are marked MIGRATE_RESERVE by
4073 * setup_zone_migrate_reserve()
4075 * bitmap is created for zone's valid pfn range. but memmap
4076 * can be created for invalid pages (for alignment)
4077 * check here not to call set_pageblock_migratetype() against
4080 if ((z
->zone_start_pfn
<= pfn
)
4081 && (pfn
< zone_end_pfn(z
))
4082 && !(pfn
& (pageblock_nr_pages
- 1)))
4083 set_pageblock_migratetype(page
, MIGRATE_MOVABLE
);
4085 INIT_LIST_HEAD(&page
->lru
);
4086 #ifdef WANT_PAGE_VIRTUAL
4087 /* The shift won't overflow because ZONE_NORMAL is below 4G. */
4088 if (!is_highmem_idx(zone
))
4089 set_page_address(page
, __va(pfn
<< PAGE_SHIFT
));
4094 static void __meminit
zone_init_free_lists(struct zone
*zone
)
4097 for_each_migratetype_order(order
, t
) {
4098 INIT_LIST_HEAD(&zone
->free_area
[order
].free_list
[t
]);
4099 zone
->free_area
[order
].nr_free
= 0;
4103 #ifndef __HAVE_ARCH_MEMMAP_INIT
4104 #define memmap_init(size, nid, zone, start_pfn) \
4105 memmap_init_zone((size), (nid), (zone), (start_pfn), MEMMAP_EARLY)
4108 static int __meminit
zone_batchsize(struct zone
*zone
)
4114 * The per-cpu-pages pools are set to around 1000th of the
4115 * size of the zone. But no more than 1/2 of a meg.
4117 * OK, so we don't know how big the cache is. So guess.
4119 batch
= zone
->managed_pages
/ 1024;
4120 if (batch
* PAGE_SIZE
> 512 * 1024)
4121 batch
= (512 * 1024) / PAGE_SIZE
;
4122 batch
/= 4; /* We effectively *= 4 below */
4127 * Clamp the batch to a 2^n - 1 value. Having a power
4128 * of 2 value was found to be more likely to have
4129 * suboptimal cache aliasing properties in some cases.
4131 * For example if 2 tasks are alternately allocating
4132 * batches of pages, one task can end up with a lot
4133 * of pages of one half of the possible page colors
4134 * and the other with pages of the other colors.
4136 batch
= rounddown_pow_of_two(batch
+ batch
/2) - 1;
4141 /* The deferral and batching of frees should be suppressed under NOMMU
4144 * The problem is that NOMMU needs to be able to allocate large chunks
4145 * of contiguous memory as there's no hardware page translation to
4146 * assemble apparent contiguous memory from discontiguous pages.
4148 * Queueing large contiguous runs of pages for batching, however,
4149 * causes the pages to actually be freed in smaller chunks. As there
4150 * can be a significant delay between the individual batches being
4151 * recycled, this leads to the once large chunks of space being
4152 * fragmented and becoming unavailable for high-order allocations.
4159 * pcp->high and pcp->batch values are related and dependent on one another:
4160 * ->batch must never be higher then ->high.
4161 * The following function updates them in a safe manner without read side
4164 * Any new users of pcp->batch and pcp->high should ensure they can cope with
4165 * those fields changing asynchronously (acording the the above rule).
4167 * mutex_is_locked(&pcp_batch_high_lock) required when calling this function
4168 * outside of boot time (or some other assurance that no concurrent updaters
4171 static void pageset_update(struct per_cpu_pages
*pcp
, unsigned long high
,
4172 unsigned long batch
)
4174 /* start with a fail safe value for batch */
4178 /* Update high, then batch, in order */
4185 /* a companion to pageset_set_high() */
4186 static void pageset_set_batch(struct per_cpu_pageset
*p
, unsigned long batch
)
4188 pageset_update(&p
->pcp
, 6 * batch
, max(1UL, 1 * batch
));
4191 static void pageset_init(struct per_cpu_pageset
*p
)
4193 struct per_cpu_pages
*pcp
;
4196 memset(p
, 0, sizeof(*p
));
4200 for (migratetype
= 0; migratetype
< MIGRATE_PCPTYPES
; migratetype
++)
4201 INIT_LIST_HEAD(&pcp
->lists
[migratetype
]);
4204 static void setup_pageset(struct per_cpu_pageset
*p
, unsigned long batch
)
4207 pageset_set_batch(p
, batch
);
4211 * pageset_set_high() sets the high water mark for hot per_cpu_pagelist
4212 * to the value high for the pageset p.
4214 static void pageset_set_high(struct per_cpu_pageset
*p
,
4217 unsigned long batch
= max(1UL, high
/ 4);
4218 if ((high
/ 4) > (PAGE_SHIFT
* 8))
4219 batch
= PAGE_SHIFT
* 8;
4221 pageset_update(&p
->pcp
, high
, batch
);
4224 static void __meminit
pageset_set_high_and_batch(struct zone
*zone
,
4225 struct per_cpu_pageset
*pcp
)
4227 if (percpu_pagelist_fraction
)
4228 pageset_set_high(pcp
,
4229 (zone
->managed_pages
/
4230 percpu_pagelist_fraction
));
4232 pageset_set_batch(pcp
, zone_batchsize(zone
));
4235 static void __meminit
zone_pageset_init(struct zone
*zone
, int cpu
)
4237 struct per_cpu_pageset
*pcp
= per_cpu_ptr(zone
->pageset
, cpu
);
4240 pageset_set_high_and_batch(zone
, pcp
);
4243 static void __meminit
setup_zone_pageset(struct zone
*zone
)
4246 zone
->pageset
= alloc_percpu(struct per_cpu_pageset
);
4247 for_each_possible_cpu(cpu
)
4248 zone_pageset_init(zone
, cpu
);
4252 * Allocate per cpu pagesets and initialize them.
4253 * Before this call only boot pagesets were available.
4255 void __init
setup_per_cpu_pageset(void)
4259 for_each_populated_zone(zone
)
4260 setup_zone_pageset(zone
);
4263 static noinline __init_refok
4264 int zone_wait_table_init(struct zone
*zone
, unsigned long zone_size_pages
)
4270 * The per-page waitqueue mechanism uses hashed waitqueues
4273 zone
->wait_table_hash_nr_entries
=
4274 wait_table_hash_nr_entries(zone_size_pages
);
4275 zone
->wait_table_bits
=
4276 wait_table_bits(zone
->wait_table_hash_nr_entries
);
4277 alloc_size
= zone
->wait_table_hash_nr_entries
4278 * sizeof(wait_queue_head_t
);
4280 if (!slab_is_available()) {
4281 zone
->wait_table
= (wait_queue_head_t
*)
4282 memblock_virt_alloc_node_nopanic(
4283 alloc_size
, zone
->zone_pgdat
->node_id
);
4286 * This case means that a zone whose size was 0 gets new memory
4287 * via memory hot-add.
4288 * But it may be the case that a new node was hot-added. In
4289 * this case vmalloc() will not be able to use this new node's
4290 * memory - this wait_table must be initialized to use this new
4291 * node itself as well.
4292 * To use this new node's memory, further consideration will be
4295 zone
->wait_table
= vmalloc(alloc_size
);
4297 if (!zone
->wait_table
)
4300 for (i
= 0; i
< zone
->wait_table_hash_nr_entries
; ++i
)
4301 init_waitqueue_head(zone
->wait_table
+ i
);
4306 static __meminit
void zone_pcp_init(struct zone
*zone
)
4309 * per cpu subsystem is not up at this point. The following code
4310 * relies on the ability of the linker to provide the
4311 * offset of a (static) per cpu variable into the per cpu area.
4313 zone
->pageset
= &boot_pageset
;
4315 if (populated_zone(zone
))
4316 printk(KERN_DEBUG
" %s zone: %lu pages, LIFO batch:%u\n",
4317 zone
->name
, zone
->present_pages
,
4318 zone_batchsize(zone
));
4321 int __meminit
init_currently_empty_zone(struct zone
*zone
,
4322 unsigned long zone_start_pfn
,
4324 enum memmap_context context
)
4326 struct pglist_data
*pgdat
= zone
->zone_pgdat
;
4328 ret
= zone_wait_table_init(zone
, size
);
4331 pgdat
->nr_zones
= zone_idx(zone
) + 1;
4333 zone
->zone_start_pfn
= zone_start_pfn
;
4335 mminit_dprintk(MMINIT_TRACE
, "memmap_init",
4336 "Initialising map node %d zone %lu pfns %lu -> %lu\n",
4338 (unsigned long)zone_idx(zone
),
4339 zone_start_pfn
, (zone_start_pfn
+ size
));
4341 zone_init_free_lists(zone
);
4346 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
4347 #ifndef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
4349 * Required by SPARSEMEM. Given a PFN, return what node the PFN is on.
4350 * Architectures may implement their own version but if add_active_range()
4351 * was used and there are no special requirements, this is a convenient
4354 int __meminit
__early_pfn_to_nid(unsigned long pfn
)
4356 unsigned long start_pfn
, end_pfn
;
4359 * NOTE: The following SMP-unsafe globals are only used early in boot
4360 * when the kernel is running single-threaded.
4362 static unsigned long __meminitdata last_start_pfn
, last_end_pfn
;
4363 static int __meminitdata last_nid
;
4365 if (last_start_pfn
<= pfn
&& pfn
< last_end_pfn
)
4368 nid
= memblock_search_pfn_nid(pfn
, &start_pfn
, &end_pfn
);
4370 last_start_pfn
= start_pfn
;
4371 last_end_pfn
= end_pfn
;
4377 #endif /* CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID */
4379 int __meminit
early_pfn_to_nid(unsigned long pfn
)
4383 nid
= __early_pfn_to_nid(pfn
);
4386 /* just returns 0 */
4390 #ifdef CONFIG_NODES_SPAN_OTHER_NODES
4391 bool __meminit
early_pfn_in_nid(unsigned long pfn
, int node
)
4395 nid
= __early_pfn_to_nid(pfn
);
4396 if (nid
>= 0 && nid
!= node
)
4403 * free_bootmem_with_active_regions - Call memblock_free_early_nid for each active range
4404 * @nid: The node to free memory on. If MAX_NUMNODES, all nodes are freed.
4405 * @max_low_pfn: The highest PFN that will be passed to memblock_free_early_nid
4407 * If an architecture guarantees that all ranges registered with
4408 * add_active_ranges() contain no holes and may be freed, this
4409 * this function may be used instead of calling memblock_free_early_nid()
4412 void __init
free_bootmem_with_active_regions(int nid
, unsigned long max_low_pfn
)
4414 unsigned long start_pfn
, end_pfn
;
4417 for_each_mem_pfn_range(i
, nid
, &start_pfn
, &end_pfn
, &this_nid
) {
4418 start_pfn
= min(start_pfn
, max_low_pfn
);
4419 end_pfn
= min(end_pfn
, max_low_pfn
);
4421 if (start_pfn
< end_pfn
)
4422 memblock_free_early_nid(PFN_PHYS(start_pfn
),
4423 (end_pfn
- start_pfn
) << PAGE_SHIFT
,
4429 * sparse_memory_present_with_active_regions - Call memory_present for each active range
4430 * @nid: The node to call memory_present for. If MAX_NUMNODES, all nodes will be used.
4432 * If an architecture guarantees that all ranges registered with
4433 * add_active_ranges() contain no holes and may be freed, this
4434 * function may be used instead of calling memory_present() manually.
4436 void __init
sparse_memory_present_with_active_regions(int nid
)
4438 unsigned long start_pfn
, end_pfn
;
4441 for_each_mem_pfn_range(i
, nid
, &start_pfn
, &end_pfn
, &this_nid
)
4442 memory_present(this_nid
, start_pfn
, end_pfn
);
4446 * get_pfn_range_for_nid - Return the start and end page frames for a node
4447 * @nid: The nid to return the range for. If MAX_NUMNODES, the min and max PFN are returned.
4448 * @start_pfn: Passed by reference. On return, it will have the node start_pfn.
4449 * @end_pfn: Passed by reference. On return, it will have the node end_pfn.
4451 * It returns the start and end page frame of a node based on information
4452 * provided by an arch calling add_active_range(). If called for a node
4453 * with no available memory, a warning is printed and the start and end
4456 void __meminit
get_pfn_range_for_nid(unsigned int nid
,
4457 unsigned long *start_pfn
, unsigned long *end_pfn
)
4459 unsigned long this_start_pfn
, this_end_pfn
;
4465 for_each_mem_pfn_range(i
, nid
, &this_start_pfn
, &this_end_pfn
, NULL
) {
4466 *start_pfn
= min(*start_pfn
, this_start_pfn
);
4467 *end_pfn
= max(*end_pfn
, this_end_pfn
);
4470 if (*start_pfn
== -1UL)
4475 * This finds a zone that can be used for ZONE_MOVABLE pages. The
4476 * assumption is made that zones within a node are ordered in monotonic
4477 * increasing memory addresses so that the "highest" populated zone is used
4479 static void __init
find_usable_zone_for_movable(void)
4482 for (zone_index
= MAX_NR_ZONES
- 1; zone_index
>= 0; zone_index
--) {
4483 if (zone_index
== ZONE_MOVABLE
)
4486 if (arch_zone_highest_possible_pfn
[zone_index
] >
4487 arch_zone_lowest_possible_pfn
[zone_index
])
4491 VM_BUG_ON(zone_index
== -1);
4492 movable_zone
= zone_index
;
4496 * The zone ranges provided by the architecture do not include ZONE_MOVABLE
4497 * because it is sized independent of architecture. Unlike the other zones,
4498 * the starting point for ZONE_MOVABLE is not fixed. It may be different
4499 * in each node depending on the size of each node and how evenly kernelcore
4500 * is distributed. This helper function adjusts the zone ranges
4501 * provided by the architecture for a given node by using the end of the
4502 * highest usable zone for ZONE_MOVABLE. This preserves the assumption that
4503 * zones within a node are in order of monotonic increases memory addresses
4505 static void __meminit
adjust_zone_range_for_zone_movable(int nid
,
4506 unsigned long zone_type
,
4507 unsigned long node_start_pfn
,
4508 unsigned long node_end_pfn
,
4509 unsigned long *zone_start_pfn
,
4510 unsigned long *zone_end_pfn
)
4512 /* Only adjust if ZONE_MOVABLE is on this node */
4513 if (zone_movable_pfn
[nid
]) {
4514 /* Size ZONE_MOVABLE */
4515 if (zone_type
== ZONE_MOVABLE
) {
4516 *zone_start_pfn
= zone_movable_pfn
[nid
];
4517 *zone_end_pfn
= min(node_end_pfn
,
4518 arch_zone_highest_possible_pfn
[movable_zone
]);
4520 /* Adjust for ZONE_MOVABLE starting within this range */
4521 } else if (*zone_start_pfn
< zone_movable_pfn
[nid
] &&
4522 *zone_end_pfn
> zone_movable_pfn
[nid
]) {
4523 *zone_end_pfn
= zone_movable_pfn
[nid
];
4525 /* Check if this whole range is within ZONE_MOVABLE */
4526 } else if (*zone_start_pfn
>= zone_movable_pfn
[nid
])
4527 *zone_start_pfn
= *zone_end_pfn
;
4532 * Return the number of pages a zone spans in a node, including holes
4533 * present_pages = zone_spanned_pages_in_node() - zone_absent_pages_in_node()
4535 static unsigned long __meminit
zone_spanned_pages_in_node(int nid
,
4536 unsigned long zone_type
,
4537 unsigned long node_start_pfn
,
4538 unsigned long node_end_pfn
,
4539 unsigned long *ignored
)
4541 unsigned long zone_start_pfn
, zone_end_pfn
;
4543 /* Get the start and end of the zone */
4544 zone_start_pfn
= arch_zone_lowest_possible_pfn
[zone_type
];
4545 zone_end_pfn
= arch_zone_highest_possible_pfn
[zone_type
];
4546 adjust_zone_range_for_zone_movable(nid
, zone_type
,
4547 node_start_pfn
, node_end_pfn
,
4548 &zone_start_pfn
, &zone_end_pfn
);
4550 /* Check that this node has pages within the zone's required range */
4551 if (zone_end_pfn
< node_start_pfn
|| zone_start_pfn
> node_end_pfn
)
4554 /* Move the zone boundaries inside the node if necessary */
4555 zone_end_pfn
= min(zone_end_pfn
, node_end_pfn
);
4556 zone_start_pfn
= max(zone_start_pfn
, node_start_pfn
);
4558 /* Return the spanned pages */
4559 return zone_end_pfn
- zone_start_pfn
;
4563 * Return the number of holes in a range on a node. If nid is MAX_NUMNODES,
4564 * then all holes in the requested range will be accounted for.
4566 unsigned long __meminit
__absent_pages_in_range(int nid
,
4567 unsigned long range_start_pfn
,
4568 unsigned long range_end_pfn
)
4570 unsigned long nr_absent
= range_end_pfn
- range_start_pfn
;
4571 unsigned long start_pfn
, end_pfn
;
4574 for_each_mem_pfn_range(i
, nid
, &start_pfn
, &end_pfn
, NULL
) {
4575 start_pfn
= clamp(start_pfn
, range_start_pfn
, range_end_pfn
);
4576 end_pfn
= clamp(end_pfn
, range_start_pfn
, range_end_pfn
);
4577 nr_absent
-= end_pfn
- start_pfn
;
4583 * absent_pages_in_range - Return number of page frames in holes within a range
4584 * @start_pfn: The start PFN to start searching for holes
4585 * @end_pfn: The end PFN to stop searching for holes
4587 * It returns the number of pages frames in memory holes within a range.
4589 unsigned long __init
absent_pages_in_range(unsigned long start_pfn
,
4590 unsigned long end_pfn
)
4592 return __absent_pages_in_range(MAX_NUMNODES
, start_pfn
, end_pfn
);
4595 /* Return the number of page frames in holes in a zone on a node */
4596 static unsigned long __meminit
zone_absent_pages_in_node(int nid
,
4597 unsigned long zone_type
,
4598 unsigned long node_start_pfn
,
4599 unsigned long node_end_pfn
,
4600 unsigned long *ignored
)
4602 unsigned long zone_low
= arch_zone_lowest_possible_pfn
[zone_type
];
4603 unsigned long zone_high
= arch_zone_highest_possible_pfn
[zone_type
];
4604 unsigned long zone_start_pfn
, zone_end_pfn
;
4606 zone_start_pfn
= clamp(node_start_pfn
, zone_low
, zone_high
);
4607 zone_end_pfn
= clamp(node_end_pfn
, zone_low
, zone_high
);
4609 adjust_zone_range_for_zone_movable(nid
, zone_type
,
4610 node_start_pfn
, node_end_pfn
,
4611 &zone_start_pfn
, &zone_end_pfn
);
4612 return __absent_pages_in_range(nid
, zone_start_pfn
, zone_end_pfn
);
4615 #else /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
4616 static inline unsigned long __meminit
zone_spanned_pages_in_node(int nid
,
4617 unsigned long zone_type
,
4618 unsigned long node_start_pfn
,
4619 unsigned long node_end_pfn
,
4620 unsigned long *zones_size
)
4622 return zones_size
[zone_type
];
4625 static inline unsigned long __meminit
zone_absent_pages_in_node(int nid
,
4626 unsigned long zone_type
,
4627 unsigned long node_start_pfn
,
4628 unsigned long node_end_pfn
,
4629 unsigned long *zholes_size
)
4634 return zholes_size
[zone_type
];
4637 #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
4639 static void __meminit
calculate_node_totalpages(struct pglist_data
*pgdat
,
4640 unsigned long node_start_pfn
,
4641 unsigned long node_end_pfn
,
4642 unsigned long *zones_size
,
4643 unsigned long *zholes_size
)
4645 unsigned long realtotalpages
, totalpages
= 0;
4648 for (i
= 0; i
< MAX_NR_ZONES
; i
++)
4649 totalpages
+= zone_spanned_pages_in_node(pgdat
->node_id
, i
,
4653 pgdat
->node_spanned_pages
= totalpages
;
4655 realtotalpages
= totalpages
;
4656 for (i
= 0; i
< MAX_NR_ZONES
; i
++)
4658 zone_absent_pages_in_node(pgdat
->node_id
, i
,
4659 node_start_pfn
, node_end_pfn
,
4661 pgdat
->node_present_pages
= realtotalpages
;
4662 printk(KERN_DEBUG
"On node %d totalpages: %lu\n", pgdat
->node_id
,
4666 #ifndef CONFIG_SPARSEMEM
4668 * Calculate the size of the zone->blockflags rounded to an unsigned long
4669 * Start by making sure zonesize is a multiple of pageblock_order by rounding
4670 * up. Then use 1 NR_PAGEBLOCK_BITS worth of bits per pageblock, finally
4671 * round what is now in bits to nearest long in bits, then return it in
4674 static unsigned long __init
usemap_size(unsigned long zone_start_pfn
, unsigned long zonesize
)
4676 unsigned long usemapsize
;
4678 zonesize
+= zone_start_pfn
& (pageblock_nr_pages
-1);
4679 usemapsize
= roundup(zonesize
, pageblock_nr_pages
);
4680 usemapsize
= usemapsize
>> pageblock_order
;
4681 usemapsize
*= NR_PAGEBLOCK_BITS
;
4682 usemapsize
= roundup(usemapsize
, 8 * sizeof(unsigned long));
4684 return usemapsize
/ 8;
4687 static void __init
setup_usemap(struct pglist_data
*pgdat
,
4689 unsigned long zone_start_pfn
,
4690 unsigned long zonesize
)
4692 unsigned long usemapsize
= usemap_size(zone_start_pfn
, zonesize
);
4693 zone
->pageblock_flags
= NULL
;
4695 zone
->pageblock_flags
=
4696 memblock_virt_alloc_node_nopanic(usemapsize
,
4700 static inline void setup_usemap(struct pglist_data
*pgdat
, struct zone
*zone
,
4701 unsigned long zone_start_pfn
, unsigned long zonesize
) {}
4702 #endif /* CONFIG_SPARSEMEM */
4704 #ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
4706 /* Initialise the number of pages represented by NR_PAGEBLOCK_BITS */
4707 void __paginginit
set_pageblock_order(void)
4711 /* Check that pageblock_nr_pages has not already been setup */
4712 if (pageblock_order
)
4715 if (HPAGE_SHIFT
> PAGE_SHIFT
)
4716 order
= HUGETLB_PAGE_ORDER
;
4718 order
= MAX_ORDER
- 1;
4721 * Assume the largest contiguous order of interest is a huge page.
4722 * This value may be variable depending on boot parameters on IA64 and
4725 pageblock_order
= order
;
4727 #else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
4730 * When CONFIG_HUGETLB_PAGE_SIZE_VARIABLE is not set, set_pageblock_order()
4731 * is unused as pageblock_order is set at compile-time. See
4732 * include/linux/pageblock-flags.h for the values of pageblock_order based on
4735 void __paginginit
set_pageblock_order(void)
4739 #endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
4741 static unsigned long __paginginit
calc_memmap_size(unsigned long spanned_pages
,
4742 unsigned long present_pages
)
4744 unsigned long pages
= spanned_pages
;
4747 * Provide a more accurate estimation if there are holes within
4748 * the zone and SPARSEMEM is in use. If there are holes within the
4749 * zone, each populated memory region may cost us one or two extra
4750 * memmap pages due to alignment because memmap pages for each
4751 * populated regions may not naturally algined on page boundary.
4752 * So the (present_pages >> 4) heuristic is a tradeoff for that.
4754 if (spanned_pages
> present_pages
+ (present_pages
>> 4) &&
4755 IS_ENABLED(CONFIG_SPARSEMEM
))
4756 pages
= present_pages
;
4758 return PAGE_ALIGN(pages
* sizeof(struct page
)) >> PAGE_SHIFT
;
4762 * Set up the zone data structures:
4763 * - mark all pages reserved
4764 * - mark all memory queues empty
4765 * - clear the memory bitmaps
4767 * NOTE: pgdat should get zeroed by caller.
4769 static void __paginginit
free_area_init_core(struct pglist_data
*pgdat
,
4770 unsigned long node_start_pfn
, unsigned long node_end_pfn
,
4771 unsigned long *zones_size
, unsigned long *zholes_size
)
4774 int nid
= pgdat
->node_id
;
4775 unsigned long zone_start_pfn
= pgdat
->node_start_pfn
;
4778 pgdat_resize_init(pgdat
);
4779 #ifdef CONFIG_NUMA_BALANCING
4780 spin_lock_init(&pgdat
->numabalancing_migrate_lock
);
4781 pgdat
->numabalancing_migrate_nr_pages
= 0;
4782 pgdat
->numabalancing_migrate_next_window
= jiffies
;
4784 init_waitqueue_head(&pgdat
->kswapd_wait
);
4785 init_waitqueue_head(&pgdat
->pfmemalloc_wait
);
4786 pgdat_page_cgroup_init(pgdat
);
4788 for (j
= 0; j
< MAX_NR_ZONES
; j
++) {
4789 struct zone
*zone
= pgdat
->node_zones
+ j
;
4790 unsigned long size
, realsize
, freesize
, memmap_pages
;
4792 size
= zone_spanned_pages_in_node(nid
, j
, node_start_pfn
,
4793 node_end_pfn
, zones_size
);
4794 realsize
= freesize
= size
- zone_absent_pages_in_node(nid
, j
,
4800 * Adjust freesize so that it accounts for how much memory
4801 * is used by this zone for memmap. This affects the watermark
4802 * and per-cpu initialisations
4804 memmap_pages
= calc_memmap_size(size
, realsize
);
4805 if (freesize
>= memmap_pages
) {
4806 freesize
-= memmap_pages
;
4809 " %s zone: %lu pages used for memmap\n",
4810 zone_names
[j
], memmap_pages
);
4813 " %s zone: %lu pages exceeds freesize %lu\n",
4814 zone_names
[j
], memmap_pages
, freesize
);
4816 /* Account for reserved pages */
4817 if (j
== 0 && freesize
> dma_reserve
) {
4818 freesize
-= dma_reserve
;
4819 printk(KERN_DEBUG
" %s zone: %lu pages reserved\n",
4820 zone_names
[0], dma_reserve
);
4823 if (!is_highmem_idx(j
))
4824 nr_kernel_pages
+= freesize
;
4825 /* Charge for highmem memmap if there are enough kernel pages */
4826 else if (nr_kernel_pages
> memmap_pages
* 2)
4827 nr_kernel_pages
-= memmap_pages
;
4828 nr_all_pages
+= freesize
;
4830 zone
->spanned_pages
= size
;
4831 zone
->present_pages
= realsize
;
4833 * Set an approximate value for lowmem here, it will be adjusted
4834 * when the bootmem allocator frees pages into the buddy system.
4835 * And all highmem pages will be managed by the buddy system.
4837 zone
->managed_pages
= is_highmem_idx(j
) ? realsize
: freesize
;
4840 zone
->min_unmapped_pages
= (freesize
*sysctl_min_unmapped_ratio
)
4842 zone
->min_slab_pages
= (freesize
* sysctl_min_slab_ratio
) / 100;
4844 zone
->name
= zone_names
[j
];
4845 spin_lock_init(&zone
->lock
);
4846 spin_lock_init(&zone
->lru_lock
);
4847 zone_seqlock_init(zone
);
4848 zone
->zone_pgdat
= pgdat
;
4849 zone_pcp_init(zone
);
4851 /* For bootup, initialized properly in watermark setup */
4852 mod_zone_page_state(zone
, NR_ALLOC_BATCH
, zone
->managed_pages
);
4854 lruvec_init(&zone
->lruvec
);
4858 set_pageblock_order();
4859 setup_usemap(pgdat
, zone
, zone_start_pfn
, size
);
4860 ret
= init_currently_empty_zone(zone
, zone_start_pfn
,
4861 size
, MEMMAP_EARLY
);
4863 memmap_init(size
, nid
, j
, zone_start_pfn
);
4864 zone_start_pfn
+= size
;
4868 static void __init_refok
alloc_node_mem_map(struct pglist_data
*pgdat
)
4870 /* Skip empty nodes */
4871 if (!pgdat
->node_spanned_pages
)
4874 #ifdef CONFIG_FLAT_NODE_MEM_MAP
4875 /* ia64 gets its own node_mem_map, before this, without bootmem */
4876 if (!pgdat
->node_mem_map
) {
4877 unsigned long size
, start
, end
;
4881 * The zone's endpoints aren't required to be MAX_ORDER
4882 * aligned but the node_mem_map endpoints must be in order
4883 * for the buddy allocator to function correctly.
4885 start
= pgdat
->node_start_pfn
& ~(MAX_ORDER_NR_PAGES
- 1);
4886 end
= pgdat_end_pfn(pgdat
);
4887 end
= ALIGN(end
, MAX_ORDER_NR_PAGES
);
4888 size
= (end
- start
) * sizeof(struct page
);
4889 map
= alloc_remap(pgdat
->node_id
, size
);
4891 map
= memblock_virt_alloc_node_nopanic(size
,
4893 pgdat
->node_mem_map
= map
+ (pgdat
->node_start_pfn
- start
);
4895 #ifndef CONFIG_NEED_MULTIPLE_NODES
4897 * With no DISCONTIG, the global mem_map is just set as node 0's
4899 if (pgdat
== NODE_DATA(0)) {
4900 mem_map
= NODE_DATA(0)->node_mem_map
;
4901 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
4902 if (page_to_pfn(mem_map
) != pgdat
->node_start_pfn
)
4903 mem_map
-= (pgdat
->node_start_pfn
- ARCH_PFN_OFFSET
);
4904 #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
4907 #endif /* CONFIG_FLAT_NODE_MEM_MAP */
4910 void __paginginit
free_area_init_node(int nid
, unsigned long *zones_size
,
4911 unsigned long node_start_pfn
, unsigned long *zholes_size
)
4913 pg_data_t
*pgdat
= NODE_DATA(nid
);
4914 unsigned long start_pfn
= 0;
4915 unsigned long end_pfn
= 0;
4917 /* pg_data_t should be reset to zero when it's allocated */
4918 WARN_ON(pgdat
->nr_zones
|| pgdat
->classzone_idx
);
4920 pgdat
->node_id
= nid
;
4921 pgdat
->node_start_pfn
= node_start_pfn
;
4922 init_zone_allows_reclaim(nid
);
4923 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
4924 get_pfn_range_for_nid(nid
, &start_pfn
, &end_pfn
);
4926 calculate_node_totalpages(pgdat
, start_pfn
, end_pfn
,
4927 zones_size
, zholes_size
);
4929 alloc_node_mem_map(pgdat
);
4930 #ifdef CONFIG_FLAT_NODE_MEM_MAP
4931 printk(KERN_DEBUG
"free_area_init_node: node %d, pgdat %08lx, node_mem_map %08lx\n",
4932 nid
, (unsigned long)pgdat
,
4933 (unsigned long)pgdat
->node_mem_map
);
4936 free_area_init_core(pgdat
, start_pfn
, end_pfn
,
4937 zones_size
, zholes_size
);
4940 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
4942 #if MAX_NUMNODES > 1
4944 * Figure out the number of possible node ids.
4946 void __init
setup_nr_node_ids(void)
4949 unsigned int highest
= 0;
4951 for_each_node_mask(node
, node_possible_map
)
4953 nr_node_ids
= highest
+ 1;
4958 * node_map_pfn_alignment - determine the maximum internode alignment
4960 * This function should be called after node map is populated and sorted.
4961 * It calculates the maximum power of two alignment which can distinguish
4964 * For example, if all nodes are 1GiB and aligned to 1GiB, the return value
4965 * would indicate 1GiB alignment with (1 << (30 - PAGE_SHIFT)). If the
4966 * nodes are shifted by 256MiB, 256MiB. Note that if only the last node is
4967 * shifted, 1GiB is enough and this function will indicate so.
4969 * This is used to test whether pfn -> nid mapping of the chosen memory
4970 * model has fine enough granularity to avoid incorrect mapping for the
4971 * populated node map.
4973 * Returns the determined alignment in pfn's. 0 if there is no alignment
4974 * requirement (single node).
4976 unsigned long __init
node_map_pfn_alignment(void)
4978 unsigned long accl_mask
= 0, last_end
= 0;
4979 unsigned long start
, end
, mask
;
4983 for_each_mem_pfn_range(i
, MAX_NUMNODES
, &start
, &end
, &nid
) {
4984 if (!start
|| last_nid
< 0 || last_nid
== nid
) {
4991 * Start with a mask granular enough to pin-point to the
4992 * start pfn and tick off bits one-by-one until it becomes
4993 * too coarse to separate the current node from the last.
4995 mask
= ~((1 << __ffs(start
)) - 1);
4996 while (mask
&& last_end
<= (start
& (mask
<< 1)))
4999 /* accumulate all internode masks */
5003 /* convert mask to number of pages */
5004 return ~accl_mask
+ 1;
5007 /* Find the lowest pfn for a node */
5008 static unsigned long __init
find_min_pfn_for_node(int nid
)
5010 unsigned long min_pfn
= ULONG_MAX
;
5011 unsigned long start_pfn
;
5014 for_each_mem_pfn_range(i
, nid
, &start_pfn
, NULL
, NULL
)
5015 min_pfn
= min(min_pfn
, start_pfn
);
5017 if (min_pfn
== ULONG_MAX
) {
5019 "Could not find start_pfn for node %d\n", nid
);
5027 * find_min_pfn_with_active_regions - Find the minimum PFN registered
5029 * It returns the minimum PFN based on information provided via
5030 * add_active_range().
5032 unsigned long __init
find_min_pfn_with_active_regions(void)
5034 return find_min_pfn_for_node(MAX_NUMNODES
);
5038 * early_calculate_totalpages()
5039 * Sum pages in active regions for movable zone.
5040 * Populate N_MEMORY for calculating usable_nodes.
5042 static unsigned long __init
early_calculate_totalpages(void)
5044 unsigned long totalpages
= 0;
5045 unsigned long start_pfn
, end_pfn
;
5048 for_each_mem_pfn_range(i
, MAX_NUMNODES
, &start_pfn
, &end_pfn
, &nid
) {
5049 unsigned long pages
= end_pfn
- start_pfn
;
5051 totalpages
+= pages
;
5053 node_set_state(nid
, N_MEMORY
);
5059 * Find the PFN the Movable zone begins in each node. Kernel memory
5060 * is spread evenly between nodes as long as the nodes have enough
5061 * memory. When they don't, some nodes will have more kernelcore than
5064 static void __init
find_zone_movable_pfns_for_nodes(void)
5067 unsigned long usable_startpfn
;
5068 unsigned long kernelcore_node
, kernelcore_remaining
;
5069 /* save the state before borrow the nodemask */
5070 nodemask_t saved_node_state
= node_states
[N_MEMORY
];
5071 unsigned long totalpages
= early_calculate_totalpages();
5072 int usable_nodes
= nodes_weight(node_states
[N_MEMORY
]);
5073 struct memblock_type
*type
= &memblock
.memory
;
5075 /* Need to find movable_zone earlier when movable_node is specified. */
5076 find_usable_zone_for_movable();
5079 * If movable_node is specified, ignore kernelcore and movablecore
5082 if (movable_node_is_enabled()) {
5083 for (i
= 0; i
< type
->cnt
; i
++) {
5084 if (!memblock_is_hotpluggable(&type
->regions
[i
]))
5087 nid
= type
->regions
[i
].nid
;
5089 usable_startpfn
= PFN_DOWN(type
->regions
[i
].base
);
5090 zone_movable_pfn
[nid
] = zone_movable_pfn
[nid
] ?
5091 min(usable_startpfn
, zone_movable_pfn
[nid
]) :
5099 * If movablecore=nn[KMG] was specified, calculate what size of
5100 * kernelcore that corresponds so that memory usable for
5101 * any allocation type is evenly spread. If both kernelcore
5102 * and movablecore are specified, then the value of kernelcore
5103 * will be used for required_kernelcore if it's greater than
5104 * what movablecore would have allowed.
5106 if (required_movablecore
) {
5107 unsigned long corepages
;
5110 * Round-up so that ZONE_MOVABLE is at least as large as what
5111 * was requested by the user
5113 required_movablecore
=
5114 roundup(required_movablecore
, MAX_ORDER_NR_PAGES
);
5115 corepages
= totalpages
- required_movablecore
;
5117 required_kernelcore
= max(required_kernelcore
, corepages
);
5120 /* If kernelcore was not specified, there is no ZONE_MOVABLE */
5121 if (!required_kernelcore
)
5124 /* usable_startpfn is the lowest possible pfn ZONE_MOVABLE can be at */
5125 usable_startpfn
= arch_zone_lowest_possible_pfn
[movable_zone
];
5128 /* Spread kernelcore memory as evenly as possible throughout nodes */
5129 kernelcore_node
= required_kernelcore
/ usable_nodes
;
5130 for_each_node_state(nid
, N_MEMORY
) {
5131 unsigned long start_pfn
, end_pfn
;
5134 * Recalculate kernelcore_node if the division per node
5135 * now exceeds what is necessary to satisfy the requested
5136 * amount of memory for the kernel
5138 if (required_kernelcore
< kernelcore_node
)
5139 kernelcore_node
= required_kernelcore
/ usable_nodes
;
5142 * As the map is walked, we track how much memory is usable
5143 * by the kernel using kernelcore_remaining. When it is
5144 * 0, the rest of the node is usable by ZONE_MOVABLE
5146 kernelcore_remaining
= kernelcore_node
;
5148 /* Go through each range of PFNs within this node */
5149 for_each_mem_pfn_range(i
, nid
, &start_pfn
, &end_pfn
, NULL
) {
5150 unsigned long size_pages
;
5152 start_pfn
= max(start_pfn
, zone_movable_pfn
[nid
]);
5153 if (start_pfn
>= end_pfn
)
5156 /* Account for what is only usable for kernelcore */
5157 if (start_pfn
< usable_startpfn
) {
5158 unsigned long kernel_pages
;
5159 kernel_pages
= min(end_pfn
, usable_startpfn
)
5162 kernelcore_remaining
-= min(kernel_pages
,
5163 kernelcore_remaining
);
5164 required_kernelcore
-= min(kernel_pages
,
5165 required_kernelcore
);
5167 /* Continue if range is now fully accounted */
5168 if (end_pfn
<= usable_startpfn
) {
5171 * Push zone_movable_pfn to the end so
5172 * that if we have to rebalance
5173 * kernelcore across nodes, we will
5174 * not double account here
5176 zone_movable_pfn
[nid
] = end_pfn
;
5179 start_pfn
= usable_startpfn
;
5183 * The usable PFN range for ZONE_MOVABLE is from
5184 * start_pfn->end_pfn. Calculate size_pages as the
5185 * number of pages used as kernelcore
5187 size_pages
= end_pfn
- start_pfn
;
5188 if (size_pages
> kernelcore_remaining
)
5189 size_pages
= kernelcore_remaining
;
5190 zone_movable_pfn
[nid
] = start_pfn
+ size_pages
;
5193 * Some kernelcore has been met, update counts and
5194 * break if the kernelcore for this node has been
5197 required_kernelcore
-= min(required_kernelcore
,
5199 kernelcore_remaining
-= size_pages
;
5200 if (!kernelcore_remaining
)
5206 * If there is still required_kernelcore, we do another pass with one
5207 * less node in the count. This will push zone_movable_pfn[nid] further
5208 * along on the nodes that still have memory until kernelcore is
5212 if (usable_nodes
&& required_kernelcore
> usable_nodes
)
5216 /* Align start of ZONE_MOVABLE on all nids to MAX_ORDER_NR_PAGES */
5217 for (nid
= 0; nid
< MAX_NUMNODES
; nid
++)
5218 zone_movable_pfn
[nid
] =
5219 roundup(zone_movable_pfn
[nid
], MAX_ORDER_NR_PAGES
);
5222 /* restore the node_state */
5223 node_states
[N_MEMORY
] = saved_node_state
;
5226 /* Any regular or high memory on that node ? */
5227 static void check_for_memory(pg_data_t
*pgdat
, int nid
)
5229 enum zone_type zone_type
;
5231 if (N_MEMORY
== N_NORMAL_MEMORY
)
5234 for (zone_type
= 0; zone_type
<= ZONE_MOVABLE
- 1; zone_type
++) {
5235 struct zone
*zone
= &pgdat
->node_zones
[zone_type
];
5236 if (populated_zone(zone
)) {
5237 node_set_state(nid
, N_HIGH_MEMORY
);
5238 if (N_NORMAL_MEMORY
!= N_HIGH_MEMORY
&&
5239 zone_type
<= ZONE_NORMAL
)
5240 node_set_state(nid
, N_NORMAL_MEMORY
);
5247 * free_area_init_nodes - Initialise all pg_data_t and zone data
5248 * @max_zone_pfn: an array of max PFNs for each zone
5250 * This will call free_area_init_node() for each active node in the system.
5251 * Using the page ranges provided by add_active_range(), the size of each
5252 * zone in each node and their holes is calculated. If the maximum PFN
5253 * between two adjacent zones match, it is assumed that the zone is empty.
5254 * For example, if arch_max_dma_pfn == arch_max_dma32_pfn, it is assumed
5255 * that arch_max_dma32_pfn has no pages. It is also assumed that a zone
5256 * starts where the previous one ended. For example, ZONE_DMA32 starts
5257 * at arch_max_dma_pfn.
5259 void __init
free_area_init_nodes(unsigned long *max_zone_pfn
)
5261 unsigned long start_pfn
, end_pfn
;
5264 /* Record where the zone boundaries are */
5265 memset(arch_zone_lowest_possible_pfn
, 0,
5266 sizeof(arch_zone_lowest_possible_pfn
));
5267 memset(arch_zone_highest_possible_pfn
, 0,
5268 sizeof(arch_zone_highest_possible_pfn
));
5269 arch_zone_lowest_possible_pfn
[0] = find_min_pfn_with_active_regions();
5270 arch_zone_highest_possible_pfn
[0] = max_zone_pfn
[0];
5271 for (i
= 1; i
< MAX_NR_ZONES
; i
++) {
5272 if (i
== ZONE_MOVABLE
)
5274 arch_zone_lowest_possible_pfn
[i
] =
5275 arch_zone_highest_possible_pfn
[i
-1];
5276 arch_zone_highest_possible_pfn
[i
] =
5277 max(max_zone_pfn
[i
], arch_zone_lowest_possible_pfn
[i
]);
5279 arch_zone_lowest_possible_pfn
[ZONE_MOVABLE
] = 0;
5280 arch_zone_highest_possible_pfn
[ZONE_MOVABLE
] = 0;
5282 /* Find the PFNs that ZONE_MOVABLE begins at in each node */
5283 memset(zone_movable_pfn
, 0, sizeof(zone_movable_pfn
));
5284 find_zone_movable_pfns_for_nodes();
5286 /* Print out the zone ranges */
5287 printk("Zone ranges:\n");
5288 for (i
= 0; i
< MAX_NR_ZONES
; i
++) {
5289 if (i
== ZONE_MOVABLE
)
5291 printk(KERN_CONT
" %-8s ", zone_names
[i
]);
5292 if (arch_zone_lowest_possible_pfn
[i
] ==
5293 arch_zone_highest_possible_pfn
[i
])
5294 printk(KERN_CONT
"empty\n");
5296 printk(KERN_CONT
"[mem %0#10lx-%0#10lx]\n",
5297 arch_zone_lowest_possible_pfn
[i
] << PAGE_SHIFT
,
5298 (arch_zone_highest_possible_pfn
[i
]
5299 << PAGE_SHIFT
) - 1);
5302 /* Print out the PFNs ZONE_MOVABLE begins at in each node */
5303 printk("Movable zone start for each node\n");
5304 for (i
= 0; i
< MAX_NUMNODES
; i
++) {
5305 if (zone_movable_pfn
[i
])
5306 printk(" Node %d: %#010lx\n", i
,
5307 zone_movable_pfn
[i
] << PAGE_SHIFT
);
5310 /* Print out the early node map */
5311 printk("Early memory node ranges\n");
5312 for_each_mem_pfn_range(i
, MAX_NUMNODES
, &start_pfn
, &end_pfn
, &nid
)
5313 printk(" node %3d: [mem %#010lx-%#010lx]\n", nid
,
5314 start_pfn
<< PAGE_SHIFT
, (end_pfn
<< PAGE_SHIFT
) - 1);
5316 /* Initialise every node */
5317 mminit_verify_pageflags_layout();
5318 setup_nr_node_ids();
5319 for_each_online_node(nid
) {
5320 pg_data_t
*pgdat
= NODE_DATA(nid
);
5321 free_area_init_node(nid
, NULL
,
5322 find_min_pfn_for_node(nid
), NULL
);
5324 /* Any memory on that node */
5325 if (pgdat
->node_present_pages
)
5326 node_set_state(nid
, N_MEMORY
);
5327 check_for_memory(pgdat
, nid
);
5331 static int __init
cmdline_parse_core(char *p
, unsigned long *core
)
5333 unsigned long long coremem
;
5337 coremem
= memparse(p
, &p
);
5338 *core
= coremem
>> PAGE_SHIFT
;
5340 /* Paranoid check that UL is enough for the coremem value */
5341 WARN_ON((coremem
>> PAGE_SHIFT
) > ULONG_MAX
);
5347 * kernelcore=size sets the amount of memory for use for allocations that
5348 * cannot be reclaimed or migrated.
5350 static int __init
cmdline_parse_kernelcore(char *p
)
5352 return cmdline_parse_core(p
, &required_kernelcore
);
5356 * movablecore=size sets the amount of memory for use for allocations that
5357 * can be reclaimed or migrated.
5359 static int __init
cmdline_parse_movablecore(char *p
)
5361 return cmdline_parse_core(p
, &required_movablecore
);
5364 early_param("kernelcore", cmdline_parse_kernelcore
);
5365 early_param("movablecore", cmdline_parse_movablecore
);
5367 #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
5369 void adjust_managed_page_count(struct page
*page
, long count
)
5371 spin_lock(&managed_page_count_lock
);
5372 page_zone(page
)->managed_pages
+= count
;
5373 totalram_pages
+= count
;
5374 #ifdef CONFIG_HIGHMEM
5375 if (PageHighMem(page
))
5376 totalhigh_pages
+= count
;
5378 spin_unlock(&managed_page_count_lock
);
5380 EXPORT_SYMBOL(adjust_managed_page_count
);
5382 unsigned long free_reserved_area(void *start
, void *end
, int poison
, char *s
)
5385 unsigned long pages
= 0;
5387 start
= (void *)PAGE_ALIGN((unsigned long)start
);
5388 end
= (void *)((unsigned long)end
& PAGE_MASK
);
5389 for (pos
= start
; pos
< end
; pos
+= PAGE_SIZE
, pages
++) {
5390 if ((unsigned int)poison
<= 0xFF)
5391 memset(pos
, poison
, PAGE_SIZE
);
5392 free_reserved_page(virt_to_page(pos
));
5396 pr_info("Freeing %s memory: %ldK (%p - %p)\n",
5397 s
, pages
<< (PAGE_SHIFT
- 10), start
, end
);
5401 EXPORT_SYMBOL(free_reserved_area
);
5403 #ifdef CONFIG_HIGHMEM
5404 void free_highmem_page(struct page
*page
)
5406 __free_reserved_page(page
);
5408 page_zone(page
)->managed_pages
++;
5414 void __init
mem_init_print_info(const char *str
)
5416 unsigned long physpages
, codesize
, datasize
, rosize
, bss_size
;
5417 unsigned long init_code_size
, init_data_size
;
5419 physpages
= get_num_physpages();
5420 codesize
= _etext
- _stext
;
5421 datasize
= _edata
- _sdata
;
5422 rosize
= __end_rodata
- __start_rodata
;
5423 bss_size
= __bss_stop
- __bss_start
;
5424 init_data_size
= __init_end
- __init_begin
;
5425 init_code_size
= _einittext
- _sinittext
;
5428 * Detect special cases and adjust section sizes accordingly:
5429 * 1) .init.* may be embedded into .data sections
5430 * 2) .init.text.* may be out of [__init_begin, __init_end],
5431 * please refer to arch/tile/kernel/vmlinux.lds.S.
5432 * 3) .rodata.* may be embedded into .text or .data sections.
5434 #define adj_init_size(start, end, size, pos, adj) \
5436 if (start <= pos && pos < end && size > adj) \
5440 adj_init_size(__init_begin
, __init_end
, init_data_size
,
5441 _sinittext
, init_code_size
);
5442 adj_init_size(_stext
, _etext
, codesize
, _sinittext
, init_code_size
);
5443 adj_init_size(_sdata
, _edata
, datasize
, __init_begin
, init_data_size
);
5444 adj_init_size(_stext
, _etext
, codesize
, __start_rodata
, rosize
);
5445 adj_init_size(_sdata
, _edata
, datasize
, __start_rodata
, rosize
);
5447 #undef adj_init_size
5449 printk("Memory: %luK/%luK available "
5450 "(%luK kernel code, %luK rwdata, %luK rodata, "
5451 "%luK init, %luK bss, %luK reserved"
5452 #ifdef CONFIG_HIGHMEM
5456 nr_free_pages() << (PAGE_SHIFT
-10), physpages
<< (PAGE_SHIFT
-10),
5457 codesize
>> 10, datasize
>> 10, rosize
>> 10,
5458 (init_data_size
+ init_code_size
) >> 10, bss_size
>> 10,
5459 (physpages
- totalram_pages
) << (PAGE_SHIFT
-10),
5460 #ifdef CONFIG_HIGHMEM
5461 totalhigh_pages
<< (PAGE_SHIFT
-10),
5463 str
? ", " : "", str
? str
: "");
5467 * set_dma_reserve - set the specified number of pages reserved in the first zone
5468 * @new_dma_reserve: The number of pages to mark reserved
5470 * The per-cpu batchsize and zone watermarks are determined by present_pages.
5471 * In the DMA zone, a significant percentage may be consumed by kernel image
5472 * and other unfreeable allocations which can skew the watermarks badly. This
5473 * function may optionally be used to account for unfreeable pages in the
5474 * first zone (e.g., ZONE_DMA). The effect will be lower watermarks and
5475 * smaller per-cpu batchsize.
5477 void __init
set_dma_reserve(unsigned long new_dma_reserve
)
5479 dma_reserve
= new_dma_reserve
;
5482 void __init
free_area_init(unsigned long *zones_size
)
5484 free_area_init_node(0, zones_size
,
5485 __pa(PAGE_OFFSET
) >> PAGE_SHIFT
, NULL
);
5488 static int page_alloc_cpu_notify(struct notifier_block
*self
,
5489 unsigned long action
, void *hcpu
)
5491 int cpu
= (unsigned long)hcpu
;
5493 if (action
== CPU_DEAD
|| action
== CPU_DEAD_FROZEN
) {
5494 lru_add_drain_cpu(cpu
);
5498 * Spill the event counters of the dead processor
5499 * into the current processors event counters.
5500 * This artificially elevates the count of the current
5503 vm_events_fold_cpu(cpu
);
5506 * Zero the differential counters of the dead processor
5507 * so that the vm statistics are consistent.
5509 * This is only okay since the processor is dead and cannot
5510 * race with what we are doing.
5512 cpu_vm_stats_fold(cpu
);
5517 void __init
page_alloc_init(void)
5519 hotcpu_notifier(page_alloc_cpu_notify
, 0);
5523 * calculate_totalreserve_pages - called when sysctl_lower_zone_reserve_ratio
5524 * or min_free_kbytes changes.
5526 static void calculate_totalreserve_pages(void)
5528 struct pglist_data
*pgdat
;
5529 unsigned long reserve_pages
= 0;
5530 enum zone_type i
, j
;
5532 for_each_online_pgdat(pgdat
) {
5533 for (i
= 0; i
< MAX_NR_ZONES
; i
++) {
5534 struct zone
*zone
= pgdat
->node_zones
+ i
;
5535 unsigned long max
= 0;
5537 /* Find valid and maximum lowmem_reserve in the zone */
5538 for (j
= i
; j
< MAX_NR_ZONES
; j
++) {
5539 if (zone
->lowmem_reserve
[j
] > max
)
5540 max
= zone
->lowmem_reserve
[j
];
5543 /* we treat the high watermark as reserved pages. */
5544 max
+= high_wmark_pages(zone
);
5546 if (max
> zone
->managed_pages
)
5547 max
= zone
->managed_pages
;
5548 reserve_pages
+= max
;
5550 * Lowmem reserves are not available to
5551 * GFP_HIGHUSER page cache allocations and
5552 * kswapd tries to balance zones to their high
5553 * watermark. As a result, neither should be
5554 * regarded as dirtyable memory, to prevent a
5555 * situation where reclaim has to clean pages
5556 * in order to balance the zones.
5558 zone
->dirty_balance_reserve
= max
;
5561 dirty_balance_reserve
= reserve_pages
;
5562 totalreserve_pages
= reserve_pages
;
5566 * setup_per_zone_lowmem_reserve - called whenever
5567 * sysctl_lower_zone_reserve_ratio changes. Ensures that each zone
5568 * has a correct pages reserved value, so an adequate number of
5569 * pages are left in the zone after a successful __alloc_pages().
5571 static void setup_per_zone_lowmem_reserve(void)
5573 struct pglist_data
*pgdat
;
5574 enum zone_type j
, idx
;
5576 for_each_online_pgdat(pgdat
) {
5577 for (j
= 0; j
< MAX_NR_ZONES
; j
++) {
5578 struct zone
*zone
= pgdat
->node_zones
+ j
;
5579 unsigned long managed_pages
= zone
->managed_pages
;
5581 zone
->lowmem_reserve
[j
] = 0;
5585 struct zone
*lower_zone
;
5589 if (sysctl_lowmem_reserve_ratio
[idx
] < 1)
5590 sysctl_lowmem_reserve_ratio
[idx
] = 1;
5592 lower_zone
= pgdat
->node_zones
+ idx
;
5593 lower_zone
->lowmem_reserve
[j
] = managed_pages
/
5594 sysctl_lowmem_reserve_ratio
[idx
];
5595 managed_pages
+= lower_zone
->managed_pages
;
5600 /* update totalreserve_pages */
5601 calculate_totalreserve_pages();
5604 static void __setup_per_zone_wmarks(void)
5606 unsigned long pages_min
= min_free_kbytes
>> (PAGE_SHIFT
- 10);
5607 unsigned long lowmem_pages
= 0;
5609 unsigned long flags
;
5611 /* Calculate total number of !ZONE_HIGHMEM pages */
5612 for_each_zone(zone
) {
5613 if (!is_highmem(zone
))
5614 lowmem_pages
+= zone
->managed_pages
;
5617 for_each_zone(zone
) {
5620 spin_lock_irqsave(&zone
->lock
, flags
);
5621 tmp
= (u64
)pages_min
* zone
->managed_pages
;
5622 do_div(tmp
, lowmem_pages
);
5623 if (is_highmem(zone
)) {
5625 * __GFP_HIGH and PF_MEMALLOC allocations usually don't
5626 * need highmem pages, so cap pages_min to a small
5629 * The WMARK_HIGH-WMARK_LOW and (WMARK_LOW-WMARK_MIN)
5630 * deltas controls asynch page reclaim, and so should
5631 * not be capped for highmem.
5633 unsigned long min_pages
;
5635 min_pages
= zone
->managed_pages
/ 1024;
5636 min_pages
= clamp(min_pages
, SWAP_CLUSTER_MAX
, 128UL);
5637 zone
->watermark
[WMARK_MIN
] = min_pages
;
5640 * If it's a lowmem zone, reserve a number of pages
5641 * proportionate to the zone's size.
5643 zone
->watermark
[WMARK_MIN
] = tmp
;
5646 zone
->watermark
[WMARK_LOW
] = min_wmark_pages(zone
) + (tmp
>> 2);
5647 zone
->watermark
[WMARK_HIGH
] = min_wmark_pages(zone
) + (tmp
>> 1);
5649 __mod_zone_page_state(zone
, NR_ALLOC_BATCH
,
5650 high_wmark_pages(zone
) -
5651 low_wmark_pages(zone
) -
5652 zone_page_state(zone
, NR_ALLOC_BATCH
));
5654 setup_zone_migrate_reserve(zone
);
5655 spin_unlock_irqrestore(&zone
->lock
, flags
);
5658 /* update totalreserve_pages */
5659 calculate_totalreserve_pages();
5663 * setup_per_zone_wmarks - called when min_free_kbytes changes
5664 * or when memory is hot-{added|removed}
5666 * Ensures that the watermark[min,low,high] values for each zone are set
5667 * correctly with respect to min_free_kbytes.
5669 void setup_per_zone_wmarks(void)
5671 mutex_lock(&zonelists_mutex
);
5672 __setup_per_zone_wmarks();
5673 mutex_unlock(&zonelists_mutex
);
5677 * The inactive anon list should be small enough that the VM never has to
5678 * do too much work, but large enough that each inactive page has a chance
5679 * to be referenced again before it is swapped out.
5681 * The inactive_anon ratio is the target ratio of ACTIVE_ANON to
5682 * INACTIVE_ANON pages on this zone's LRU, maintained by the
5683 * pageout code. A zone->inactive_ratio of 3 means 3:1 or 25% of
5684 * the anonymous pages are kept on the inactive list.
5687 * memory ratio inactive anon
5688 * -------------------------------------
5697 static void __meminit
calculate_zone_inactive_ratio(struct zone
*zone
)
5699 unsigned int gb
, ratio
;
5701 /* Zone size in gigabytes */
5702 gb
= zone
->managed_pages
>> (30 - PAGE_SHIFT
);
5704 ratio
= int_sqrt(10 * gb
);
5708 zone
->inactive_ratio
= ratio
;
5711 static void __meminit
setup_per_zone_inactive_ratio(void)
5716 calculate_zone_inactive_ratio(zone
);
5720 * Initialise min_free_kbytes.
5722 * For small machines we want it small (128k min). For large machines
5723 * we want it large (64MB max). But it is not linear, because network
5724 * bandwidth does not increase linearly with machine size. We use
5726 * min_free_kbytes = 4 * sqrt(lowmem_kbytes), for better accuracy:
5727 * min_free_kbytes = sqrt(lowmem_kbytes * 16)
5743 int __meminit
init_per_zone_wmark_min(void)
5745 unsigned long lowmem_kbytes
;
5746 int new_min_free_kbytes
;
5748 lowmem_kbytes
= nr_free_buffer_pages() * (PAGE_SIZE
>> 10);
5749 new_min_free_kbytes
= int_sqrt(lowmem_kbytes
* 16);
5751 if (new_min_free_kbytes
> user_min_free_kbytes
) {
5752 min_free_kbytes
= new_min_free_kbytes
;
5753 if (min_free_kbytes
< 128)
5754 min_free_kbytes
= 128;
5755 if (min_free_kbytes
> 65536)
5756 min_free_kbytes
= 65536;
5758 pr_warn("min_free_kbytes is not updated to %d because user defined value %d is preferred\n",
5759 new_min_free_kbytes
, user_min_free_kbytes
);
5761 setup_per_zone_wmarks();
5762 refresh_zone_stat_thresholds();
5763 setup_per_zone_lowmem_reserve();
5764 setup_per_zone_inactive_ratio();
5767 module_init(init_per_zone_wmark_min
)
5770 * min_free_kbytes_sysctl_handler - just a wrapper around proc_dointvec() so
5771 * that we can call two helper functions whenever min_free_kbytes
5774 int min_free_kbytes_sysctl_handler(ctl_table
*table
, int write
,
5775 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
5779 rc
= proc_dointvec_minmax(table
, write
, buffer
, length
, ppos
);
5784 user_min_free_kbytes
= min_free_kbytes
;
5785 setup_per_zone_wmarks();
5791 int sysctl_min_unmapped_ratio_sysctl_handler(ctl_table
*table
, int write
,
5792 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
5797 rc
= proc_dointvec_minmax(table
, write
, buffer
, length
, ppos
);
5802 zone
->min_unmapped_pages
= (zone
->managed_pages
*
5803 sysctl_min_unmapped_ratio
) / 100;
5807 int sysctl_min_slab_ratio_sysctl_handler(ctl_table
*table
, int write
,
5808 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
5813 rc
= proc_dointvec_minmax(table
, write
, buffer
, length
, ppos
);
5818 zone
->min_slab_pages
= (zone
->managed_pages
*
5819 sysctl_min_slab_ratio
) / 100;
5825 * lowmem_reserve_ratio_sysctl_handler - just a wrapper around
5826 * proc_dointvec() so that we can call setup_per_zone_lowmem_reserve()
5827 * whenever sysctl_lowmem_reserve_ratio changes.
5829 * The reserve ratio obviously has absolutely no relation with the
5830 * minimum watermarks. The lowmem reserve ratio can only make sense
5831 * if in function of the boot time zone sizes.
5833 int lowmem_reserve_ratio_sysctl_handler(ctl_table
*table
, int write
,
5834 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
5836 proc_dointvec_minmax(table
, write
, buffer
, length
, ppos
);
5837 setup_per_zone_lowmem_reserve();
5842 * percpu_pagelist_fraction - changes the pcp->high for each zone on each
5843 * cpu. It is the fraction of total pages in each zone that a hot per cpu
5844 * pagelist can have before it gets flushed back to buddy allocator.
5846 int percpu_pagelist_fraction_sysctl_handler(ctl_table
*table
, int write
,
5847 void __user
*buffer
, size_t *length
, loff_t
*ppos
)
5853 ret
= proc_dointvec_minmax(table
, write
, buffer
, length
, ppos
);
5854 if (!write
|| (ret
< 0))
5857 mutex_lock(&pcp_batch_high_lock
);
5858 for_each_populated_zone(zone
) {
5860 high
= zone
->managed_pages
/ percpu_pagelist_fraction
;
5861 for_each_possible_cpu(cpu
)
5862 pageset_set_high(per_cpu_ptr(zone
->pageset
, cpu
),
5865 mutex_unlock(&pcp_batch_high_lock
);
5869 int hashdist
= HASHDIST_DEFAULT
;
5872 static int __init
set_hashdist(char *str
)
5876 hashdist
= simple_strtoul(str
, &str
, 0);
5879 __setup("hashdist=", set_hashdist
);
5883 * allocate a large system hash table from bootmem
5884 * - it is assumed that the hash table must contain an exact power-of-2
5885 * quantity of entries
5886 * - limit is the number of hash buckets, not the total allocation size
5888 void *__init
alloc_large_system_hash(const char *tablename
,
5889 unsigned long bucketsize
,
5890 unsigned long numentries
,
5893 unsigned int *_hash_shift
,
5894 unsigned int *_hash_mask
,
5895 unsigned long low_limit
,
5896 unsigned long high_limit
)
5898 unsigned long long max
= high_limit
;
5899 unsigned long log2qty
, size
;
5902 /* allow the kernel cmdline to have a say */
5904 /* round applicable memory size up to nearest megabyte */
5905 numentries
= nr_kernel_pages
;
5907 /* It isn't necessary when PAGE_SIZE >= 1MB */
5908 if (PAGE_SHIFT
< 20)
5909 numentries
= round_up(numentries
, (1<<20)/PAGE_SIZE
);
5911 /* limit to 1 bucket per 2^scale bytes of low memory */
5912 if (scale
> PAGE_SHIFT
)
5913 numentries
>>= (scale
- PAGE_SHIFT
);
5915 numentries
<<= (PAGE_SHIFT
- scale
);
5917 /* Make sure we've got at least a 0-order allocation.. */
5918 if (unlikely(flags
& HASH_SMALL
)) {
5919 /* Makes no sense without HASH_EARLY */
5920 WARN_ON(!(flags
& HASH_EARLY
));
5921 if (!(numentries
>> *_hash_shift
)) {
5922 numentries
= 1UL << *_hash_shift
;
5923 BUG_ON(!numentries
);
5925 } else if (unlikely((numentries
* bucketsize
) < PAGE_SIZE
))
5926 numentries
= PAGE_SIZE
/ bucketsize
;
5928 numentries
= roundup_pow_of_two(numentries
);
5930 /* limit allocation size to 1/16 total memory by default */
5932 max
= ((unsigned long long)nr_all_pages
<< PAGE_SHIFT
) >> 4;
5933 do_div(max
, bucketsize
);
5935 max
= min(max
, 0x80000000ULL
);
5937 if (numentries
< low_limit
)
5938 numentries
= low_limit
;
5939 if (numentries
> max
)
5942 log2qty
= ilog2(numentries
);
5945 size
= bucketsize
<< log2qty
;
5946 if (flags
& HASH_EARLY
)
5947 table
= memblock_virt_alloc_nopanic(size
, 0);
5949 table
= __vmalloc(size
, GFP_ATOMIC
, PAGE_KERNEL
);
5952 * If bucketsize is not a power-of-two, we may free
5953 * some pages at the end of hash table which
5954 * alloc_pages_exact() automatically does
5956 if (get_order(size
) < MAX_ORDER
) {
5957 table
= alloc_pages_exact(size
, GFP_ATOMIC
);
5958 kmemleak_alloc(table
, size
, 1, GFP_ATOMIC
);
5961 } while (!table
&& size
> PAGE_SIZE
&& --log2qty
);
5964 panic("Failed to allocate %s hash table\n", tablename
);
5966 printk(KERN_INFO
"%s hash table entries: %ld (order: %d, %lu bytes)\n",
5969 ilog2(size
) - PAGE_SHIFT
,
5973 *_hash_shift
= log2qty
;
5975 *_hash_mask
= (1 << log2qty
) - 1;
5980 /* Return a pointer to the bitmap storing bits affecting a block of pages */
5981 static inline unsigned long *get_pageblock_bitmap(struct zone
*zone
,
5984 #ifdef CONFIG_SPARSEMEM
5985 return __pfn_to_section(pfn
)->pageblock_flags
;
5987 return zone
->pageblock_flags
;
5988 #endif /* CONFIG_SPARSEMEM */
5991 static inline int pfn_to_bitidx(struct zone
*zone
, unsigned long pfn
)
5993 #ifdef CONFIG_SPARSEMEM
5994 pfn
&= (PAGES_PER_SECTION
-1);
5995 return (pfn
>> pageblock_order
) * NR_PAGEBLOCK_BITS
;
5997 pfn
= pfn
- round_down(zone
->zone_start_pfn
, pageblock_nr_pages
);
5998 return (pfn
>> pageblock_order
) * NR_PAGEBLOCK_BITS
;
5999 #endif /* CONFIG_SPARSEMEM */
6003 * get_pageblock_flags_group - Return the requested group of flags for the pageblock_nr_pages block of pages
6004 * @page: The page within the block of interest
6005 * @start_bitidx: The first bit of interest to retrieve
6006 * @end_bitidx: The last bit of interest
6007 * returns pageblock_bits flags
6009 unsigned long get_pageblock_flags_group(struct page
*page
,
6010 int start_bitidx
, int end_bitidx
)
6013 unsigned long *bitmap
;
6014 unsigned long pfn
, bitidx
;
6015 unsigned long flags
= 0;
6016 unsigned long value
= 1;
6018 zone
= page_zone(page
);
6019 pfn
= page_to_pfn(page
);
6020 bitmap
= get_pageblock_bitmap(zone
, pfn
);
6021 bitidx
= pfn_to_bitidx(zone
, pfn
);
6023 for (; start_bitidx
<= end_bitidx
; start_bitidx
++, value
<<= 1)
6024 if (test_bit(bitidx
+ start_bitidx
, bitmap
))
6031 * set_pageblock_flags_group - Set the requested group of flags for a pageblock_nr_pages block of pages
6032 * @page: The page within the block of interest
6033 * @start_bitidx: The first bit of interest
6034 * @end_bitidx: The last bit of interest
6035 * @flags: The flags to set
6037 void set_pageblock_flags_group(struct page
*page
, unsigned long flags
,
6038 int start_bitidx
, int end_bitidx
)
6041 unsigned long *bitmap
;
6042 unsigned long pfn
, bitidx
;
6043 unsigned long value
= 1;
6045 zone
= page_zone(page
);
6046 pfn
= page_to_pfn(page
);
6047 bitmap
= get_pageblock_bitmap(zone
, pfn
);
6048 bitidx
= pfn_to_bitidx(zone
, pfn
);
6049 VM_BUG_ON_PAGE(!zone_spans_pfn(zone
, pfn
), page
);
6051 for (; start_bitidx
<= end_bitidx
; start_bitidx
++, value
<<= 1)
6053 __set_bit(bitidx
+ start_bitidx
, bitmap
);
6055 __clear_bit(bitidx
+ start_bitidx
, bitmap
);
6059 * This function checks whether pageblock includes unmovable pages or not.
6060 * If @count is not zero, it is okay to include less @count unmovable pages
6062 * PageLRU check without isolation or lru_lock could race so that
6063 * MIGRATE_MOVABLE block might include unmovable pages. It means you can't
6064 * expect this function should be exact.
6066 bool has_unmovable_pages(struct zone
*zone
, struct page
*page
, int count
,
6067 bool skip_hwpoisoned_pages
)
6069 unsigned long pfn
, iter
, found
;
6073 * For avoiding noise data, lru_add_drain_all() should be called
6074 * If ZONE_MOVABLE, the zone never contains unmovable pages
6076 if (zone_idx(zone
) == ZONE_MOVABLE
)
6078 mt
= get_pageblock_migratetype(page
);
6079 if (mt
== MIGRATE_MOVABLE
|| is_migrate_cma(mt
))
6082 pfn
= page_to_pfn(page
);
6083 for (found
= 0, iter
= 0; iter
< pageblock_nr_pages
; iter
++) {
6084 unsigned long check
= pfn
+ iter
;
6086 if (!pfn_valid_within(check
))
6089 page
= pfn_to_page(check
);
6092 * Hugepages are not in LRU lists, but they're movable.
6093 * We need not scan over tail pages bacause we don't
6094 * handle each tail page individually in migration.
6096 if (PageHuge(page
)) {
6097 iter
= round_up(iter
+ 1, 1<<compound_order(page
)) - 1;
6102 * We can't use page_count without pin a page
6103 * because another CPU can free compound page.
6104 * This check already skips compound tails of THP
6105 * because their page->_count is zero at all time.
6107 if (!atomic_read(&page
->_count
)) {
6108 if (PageBuddy(page
))
6109 iter
+= (1 << page_order(page
)) - 1;
6114 * The HWPoisoned page may be not in buddy system, and
6115 * page_count() is not 0.
6117 if (skip_hwpoisoned_pages
&& PageHWPoison(page
))
6123 * If there are RECLAIMABLE pages, we need to check it.
6124 * But now, memory offline itself doesn't call shrink_slab()
6125 * and it still to be fixed.
6128 * If the page is not RAM, page_count()should be 0.
6129 * we don't need more check. This is an _used_ not-movable page.
6131 * The problematic thing here is PG_reserved pages. PG_reserved
6132 * is set to both of a memory hole page and a _used_ kernel
6141 bool is_pageblock_removable_nolock(struct page
*page
)
6147 * We have to be careful here because we are iterating over memory
6148 * sections which are not zone aware so we might end up outside of
6149 * the zone but still within the section.
6150 * We have to take care about the node as well. If the node is offline
6151 * its NODE_DATA will be NULL - see page_zone.
6153 if (!node_online(page_to_nid(page
)))
6156 zone
= page_zone(page
);
6157 pfn
= page_to_pfn(page
);
6158 if (!zone_spans_pfn(zone
, pfn
))
6161 return !has_unmovable_pages(zone
, page
, 0, true);
6166 static unsigned long pfn_max_align_down(unsigned long pfn
)
6168 return pfn
& ~(max_t(unsigned long, MAX_ORDER_NR_PAGES
,
6169 pageblock_nr_pages
) - 1);
6172 static unsigned long pfn_max_align_up(unsigned long pfn
)
6174 return ALIGN(pfn
, max_t(unsigned long, MAX_ORDER_NR_PAGES
,
6175 pageblock_nr_pages
));
6178 /* [start, end) must belong to a single zone. */
6179 static int __alloc_contig_migrate_range(struct compact_control
*cc
,
6180 unsigned long start
, unsigned long end
)
6182 /* This function is based on compact_zone() from compaction.c. */
6183 unsigned long nr_reclaimed
;
6184 unsigned long pfn
= start
;
6185 unsigned int tries
= 0;
6190 while (pfn
< end
|| !list_empty(&cc
->migratepages
)) {
6191 if (fatal_signal_pending(current
)) {
6196 if (list_empty(&cc
->migratepages
)) {
6197 cc
->nr_migratepages
= 0;
6198 pfn
= isolate_migratepages_range(cc
->zone
, cc
,
6205 } else if (++tries
== 5) {
6206 ret
= ret
< 0 ? ret
: -EBUSY
;
6210 nr_reclaimed
= reclaim_clean_pages_from_list(cc
->zone
,
6212 cc
->nr_migratepages
-= nr_reclaimed
;
6214 ret
= migrate_pages(&cc
->migratepages
, alloc_migrate_target
,
6215 0, MIGRATE_SYNC
, MR_CMA
);
6218 putback_movable_pages(&cc
->migratepages
);
6225 * alloc_contig_range() -- tries to allocate given range of pages
6226 * @start: start PFN to allocate
6227 * @end: one-past-the-last PFN to allocate
6228 * @migratetype: migratetype of the underlaying pageblocks (either
6229 * #MIGRATE_MOVABLE or #MIGRATE_CMA). All pageblocks
6230 * in range must have the same migratetype and it must
6231 * be either of the two.
6233 * The PFN range does not have to be pageblock or MAX_ORDER_NR_PAGES
6234 * aligned, however it's the caller's responsibility to guarantee that
6235 * we are the only thread that changes migrate type of pageblocks the
6238 * The PFN range must belong to a single zone.
6240 * Returns zero on success or negative error code. On success all
6241 * pages which PFN is in [start, end) are allocated for the caller and
6242 * need to be freed with free_contig_range().
6244 int alloc_contig_range(unsigned long start
, unsigned long end
,
6245 unsigned migratetype
)
6247 unsigned long outer_start
, outer_end
;
6250 struct compact_control cc
= {
6251 .nr_migratepages
= 0,
6253 .zone
= page_zone(pfn_to_page(start
)),
6255 .ignore_skip_hint
= true,
6257 INIT_LIST_HEAD(&cc
.migratepages
);
6260 * What we do here is we mark all pageblocks in range as
6261 * MIGRATE_ISOLATE. Because pageblock and max order pages may
6262 * have different sizes, and due to the way page allocator
6263 * work, we align the range to biggest of the two pages so
6264 * that page allocator won't try to merge buddies from
6265 * different pageblocks and change MIGRATE_ISOLATE to some
6266 * other migration type.
6268 * Once the pageblocks are marked as MIGRATE_ISOLATE, we
6269 * migrate the pages from an unaligned range (ie. pages that
6270 * we are interested in). This will put all the pages in
6271 * range back to page allocator as MIGRATE_ISOLATE.
6273 * When this is done, we take the pages in range from page
6274 * allocator removing them from the buddy system. This way
6275 * page allocator will never consider using them.
6277 * This lets us mark the pageblocks back as
6278 * MIGRATE_CMA/MIGRATE_MOVABLE so that free pages in the
6279 * aligned range but not in the unaligned, original range are
6280 * put back to page allocator so that buddy can use them.
6283 ret
= start_isolate_page_range(pfn_max_align_down(start
),
6284 pfn_max_align_up(end
), migratetype
,
6289 ret
= __alloc_contig_migrate_range(&cc
, start
, end
);
6294 * Pages from [start, end) are within a MAX_ORDER_NR_PAGES
6295 * aligned blocks that are marked as MIGRATE_ISOLATE. What's
6296 * more, all pages in [start, end) are free in page allocator.
6297 * What we are going to do is to allocate all pages from
6298 * [start, end) (that is remove them from page allocator).
6300 * The only problem is that pages at the beginning and at the
6301 * end of interesting range may be not aligned with pages that
6302 * page allocator holds, ie. they can be part of higher order
6303 * pages. Because of this, we reserve the bigger range and
6304 * once this is done free the pages we are not interested in.
6306 * We don't have to hold zone->lock here because the pages are
6307 * isolated thus they won't get removed from buddy.
6310 lru_add_drain_all();
6314 outer_start
= start
;
6315 while (!PageBuddy(pfn_to_page(outer_start
))) {
6316 if (++order
>= MAX_ORDER
) {
6320 outer_start
&= ~0UL << order
;
6323 /* Make sure the range is really isolated. */
6324 if (test_pages_isolated(outer_start
, end
, false)) {
6325 pr_warn("alloc_contig_range test_pages_isolated(%lx, %lx) failed\n",
6332 /* Grab isolated pages from freelists. */
6333 outer_end
= isolate_freepages_range(&cc
, outer_start
, end
);
6339 /* Free head and tail (if any) */
6340 if (start
!= outer_start
)
6341 free_contig_range(outer_start
, start
- outer_start
);
6342 if (end
!= outer_end
)
6343 free_contig_range(end
, outer_end
- end
);
6346 undo_isolate_page_range(pfn_max_align_down(start
),
6347 pfn_max_align_up(end
), migratetype
);
6351 void free_contig_range(unsigned long pfn
, unsigned nr_pages
)
6353 unsigned int count
= 0;
6355 for (; nr_pages
--; pfn
++) {
6356 struct page
*page
= pfn_to_page(pfn
);
6358 count
+= page_count(page
) != 1;
6361 WARN(count
!= 0, "%d pages are still in use!\n", count
);
6365 #ifdef CONFIG_MEMORY_HOTPLUG
6367 * The zone indicated has a new number of managed_pages; batch sizes and percpu
6368 * page high values need to be recalulated.
6370 void __meminit
zone_pcp_update(struct zone
*zone
)
6373 mutex_lock(&pcp_batch_high_lock
);
6374 for_each_possible_cpu(cpu
)
6375 pageset_set_high_and_batch(zone
,
6376 per_cpu_ptr(zone
->pageset
, cpu
));
6377 mutex_unlock(&pcp_batch_high_lock
);
6381 void zone_pcp_reset(struct zone
*zone
)
6383 unsigned long flags
;
6385 struct per_cpu_pageset
*pset
;
6387 /* avoid races with drain_pages() */
6388 local_irq_save(flags
);
6389 if (zone
->pageset
!= &boot_pageset
) {
6390 for_each_online_cpu(cpu
) {
6391 pset
= per_cpu_ptr(zone
->pageset
, cpu
);
6392 drain_zonestat(zone
, pset
);
6394 free_percpu(zone
->pageset
);
6395 zone
->pageset
= &boot_pageset
;
6397 local_irq_restore(flags
);
6400 #ifdef CONFIG_MEMORY_HOTREMOVE
6402 * All pages in the range must be isolated before calling this.
6405 __offline_isolated_pages(unsigned long start_pfn
, unsigned long end_pfn
)
6411 unsigned long flags
;
6412 /* find the first valid pfn */
6413 for (pfn
= start_pfn
; pfn
< end_pfn
; pfn
++)
6418 zone
= page_zone(pfn_to_page(pfn
));
6419 spin_lock_irqsave(&zone
->lock
, flags
);
6421 while (pfn
< end_pfn
) {
6422 if (!pfn_valid(pfn
)) {
6426 page
= pfn_to_page(pfn
);
6428 * The HWPoisoned page may be not in buddy system, and
6429 * page_count() is not 0.
6431 if (unlikely(!PageBuddy(page
) && PageHWPoison(page
))) {
6433 SetPageReserved(page
);
6437 BUG_ON(page_count(page
));
6438 BUG_ON(!PageBuddy(page
));
6439 order
= page_order(page
);
6440 #ifdef CONFIG_DEBUG_VM
6441 printk(KERN_INFO
"remove from free list %lx %d %lx\n",
6442 pfn
, 1 << order
, end_pfn
);
6444 list_del(&page
->lru
);
6445 rmv_page_order(page
);
6446 zone
->free_area
[order
].nr_free
--;
6447 for (i
= 0; i
< (1 << order
); i
++)
6448 SetPageReserved((page
+i
));
6449 pfn
+= (1 << order
);
6451 spin_unlock_irqrestore(&zone
->lock
, flags
);
6455 #ifdef CONFIG_MEMORY_FAILURE
6456 bool is_free_buddy_page(struct page
*page
)
6458 struct zone
*zone
= page_zone(page
);
6459 unsigned long pfn
= page_to_pfn(page
);
6460 unsigned long flags
;
6463 spin_lock_irqsave(&zone
->lock
, flags
);
6464 for (order
= 0; order
< MAX_ORDER
; order
++) {
6465 struct page
*page_head
= page
- (pfn
& ((1 << order
) - 1));
6467 if (PageBuddy(page_head
) && page_order(page_head
) >= order
)
6470 spin_unlock_irqrestore(&zone
->lock
, flags
);
6472 return order
< MAX_ORDER
;
6476 static const struct trace_print_flags pageflag_names
[] = {
6477 {1UL << PG_locked
, "locked" },
6478 {1UL << PG_error
, "error" },
6479 {1UL << PG_referenced
, "referenced" },
6480 {1UL << PG_uptodate
, "uptodate" },
6481 {1UL << PG_dirty
, "dirty" },
6482 {1UL << PG_lru
, "lru" },
6483 {1UL << PG_active
, "active" },
6484 {1UL << PG_slab
, "slab" },
6485 {1UL << PG_owner_priv_1
, "owner_priv_1" },
6486 {1UL << PG_arch_1
, "arch_1" },
6487 {1UL << PG_reserved
, "reserved" },
6488 {1UL << PG_private
, "private" },
6489 {1UL << PG_private_2
, "private_2" },
6490 {1UL << PG_writeback
, "writeback" },
6491 #ifdef CONFIG_PAGEFLAGS_EXTENDED
6492 {1UL << PG_head
, "head" },
6493 {1UL << PG_tail
, "tail" },
6495 {1UL << PG_compound
, "compound" },
6497 {1UL << PG_swapcache
, "swapcache" },
6498 {1UL << PG_mappedtodisk
, "mappedtodisk" },
6499 {1UL << PG_reclaim
, "reclaim" },
6500 {1UL << PG_swapbacked
, "swapbacked" },
6501 {1UL << PG_unevictable
, "unevictable" },
6503 {1UL << PG_mlocked
, "mlocked" },
6505 #ifdef CONFIG_ARCH_USES_PG_UNCACHED
6506 {1UL << PG_uncached
, "uncached" },
6508 #ifdef CONFIG_MEMORY_FAILURE
6509 {1UL << PG_hwpoison
, "hwpoison" },
6511 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
6512 {1UL << PG_compound_lock
, "compound_lock" },
6516 static void dump_page_flags(unsigned long flags
)
6518 const char *delim
= "";
6522 BUILD_BUG_ON(ARRAY_SIZE(pageflag_names
) != __NR_PAGEFLAGS
);
6524 printk(KERN_ALERT
"page flags: %#lx(", flags
);
6526 /* remove zone id */
6527 flags
&= (1UL << NR_PAGEFLAGS
) - 1;
6529 for (i
= 0; i
< ARRAY_SIZE(pageflag_names
) && flags
; i
++) {
6531 mask
= pageflag_names
[i
].mask
;
6532 if ((flags
& mask
) != mask
)
6536 printk("%s%s", delim
, pageflag_names
[i
].name
);
6540 /* check for left over flags */
6542 printk("%s%#lx", delim
, flags
);
6547 void dump_page_badflags(struct page
*page
, char *reason
, unsigned long badflags
)
6550 "page:%p count:%d mapcount:%d mapping:%p index:%#lx\n",
6551 page
, atomic_read(&page
->_count
), page_mapcount(page
),
6552 page
->mapping
, page
->index
);
6553 dump_page_flags(page
->flags
);
6555 pr_alert("page dumped because: %s\n", reason
);
6556 if (page
->flags
& badflags
) {
6557 pr_alert("bad because of flags:\n");
6558 dump_page_flags(page
->flags
& badflags
);
6560 mem_cgroup_print_bad_page(page
);
6563 void dump_page(struct page
*page
, char *reason
)
6565 dump_page_badflags(page
, reason
, 0);
6567 EXPORT_SYMBOL_GPL(dump_page
);