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/config.h>
18 #include <linux/stddef.h>
20 #include <linux/swap.h>
21 #include <linux/interrupt.h>
22 #include <linux/pagemap.h>
23 #include <linux/bootmem.h>
24 #include <linux/compiler.h>
25 #include <linux/kernel.h>
26 #include <linux/module.h>
27 #include <linux/suspend.h>
28 #include <linux/pagevec.h>
29 #include <linux/blkdev.h>
30 #include <linux/slab.h>
31 #include <linux/notifier.h>
32 #include <linux/topology.h>
33 #include <linux/sysctl.h>
34 #include <linux/cpu.h>
35 #include <linux/cpuset.h>
36 #include <linux/memory_hotplug.h>
37 #include <linux/nodemask.h>
38 #include <linux/vmalloc.h>
40 #include <asm/tlbflush.h>
44 * MCD - HACK: Find somewhere to initialize this EARLY, or make this
47 nodemask_t node_online_map __read_mostly
= { { [0] = 1UL } };
48 EXPORT_SYMBOL(node_online_map
);
49 nodemask_t node_possible_map __read_mostly
= NODE_MASK_ALL
;
50 EXPORT_SYMBOL(node_possible_map
);
51 struct pglist_data
*pgdat_list __read_mostly
;
52 unsigned long totalram_pages __read_mostly
;
53 unsigned long totalhigh_pages __read_mostly
;
57 * results with 256, 32 in the lowmem_reserve sysctl:
58 * 1G machine -> (16M dma, 800M-16M normal, 1G-800M high)
59 * 1G machine -> (16M dma, 784M normal, 224M high)
60 * NORMAL allocation will leave 784M/256 of ram reserved in the ZONE_DMA
61 * HIGHMEM allocation will leave 224M/32 of ram reserved in ZONE_NORMAL
62 * HIGHMEM allocation will (224M+784M)/256 of ram reserved in ZONE_DMA
64 int sysctl_lowmem_reserve_ratio
[MAX_NR_ZONES
-1] = { 256, 32 };
66 EXPORT_SYMBOL(totalram_pages
);
69 * Used by page_zone() to look up the address of the struct zone whose
70 * id is encoded in the upper bits of page->flags
72 struct zone
*zone_table
[1 << ZONETABLE_SHIFT
] __read_mostly
;
73 EXPORT_SYMBOL(zone_table
);
75 static char *zone_names
[MAX_NR_ZONES
] = { "DMA", "Normal", "HighMem" };
76 int min_free_kbytes
= 1024;
78 unsigned long __initdata nr_kernel_pages
;
79 unsigned long __initdata nr_all_pages
;
81 static int page_outside_zone_boundaries(struct zone
*zone
, struct page
*page
)
85 unsigned long pfn
= page_to_pfn(page
);
88 seq
= zone_span_seqbegin(zone
);
89 if (pfn
>= zone
->zone_start_pfn
+ zone
->spanned_pages
)
91 else if (pfn
< zone
->zone_start_pfn
)
93 } while (zone_span_seqretry(zone
, seq
));
98 static int page_is_consistent(struct zone
*zone
, struct page
*page
)
100 #ifdef CONFIG_HOLES_IN_ZONE
101 if (!pfn_valid(page_to_pfn(page
)))
104 if (zone
!= page_zone(page
))
110 * Temporary debugging check for pages not lying within a given zone.
112 static int bad_range(struct zone
*zone
, struct page
*page
)
114 if (page_outside_zone_boundaries(zone
, page
))
116 if (!page_is_consistent(zone
, page
))
122 static void bad_page(const char *function
, struct page
*page
)
124 printk(KERN_EMERG
"Bad page state at %s (in process '%s', page %p)\n",
125 function
, current
->comm
, page
);
126 printk(KERN_EMERG
"flags:0x%0*lx mapping:%p mapcount:%d count:%d\n",
127 (int)(2*sizeof(page_flags_t
)), (unsigned long)page
->flags
,
128 page
->mapping
, page_mapcount(page
), page_count(page
));
129 printk(KERN_EMERG
"Backtrace:\n");
131 printk(KERN_EMERG
"Trying to fix it up, but a reboot is needed\n");
132 page
->flags
&= ~(1 << PG_lru
|
142 set_page_count(page
, 0);
143 reset_page_mapcount(page
);
144 page
->mapping
= NULL
;
145 add_taint(TAINT_BAD_PAGE
);
148 #ifndef CONFIG_HUGETLB_PAGE
149 #define prep_compound_page(page, order) do { } while (0)
150 #define destroy_compound_page(page, order) do { } while (0)
153 * Higher-order pages are called "compound pages". They are structured thusly:
155 * The first PAGE_SIZE page is called the "head page".
157 * The remaining PAGE_SIZE pages are called "tail pages".
159 * All pages have PG_compound set. All pages have their ->private pointing at
160 * the head page (even the head page has this).
162 * The first tail page's ->mapping, if non-zero, holds the address of the
163 * compound page's put_page() function.
165 * The order of the allocation is stored in the first tail page's ->index
166 * This is only for debug at present. This usage means that zero-order pages
167 * may not be compound.
169 static void prep_compound_page(struct page
*page
, unsigned long order
)
172 int nr_pages
= 1 << order
;
174 page
[1].mapping
= NULL
;
175 page
[1].index
= order
;
176 for (i
= 0; i
< nr_pages
; i
++) {
177 struct page
*p
= page
+ i
;
180 set_page_private(p
, (unsigned long)page
);
184 static void destroy_compound_page(struct page
*page
, unsigned long order
)
187 int nr_pages
= 1 << order
;
189 if (!PageCompound(page
))
192 if (page
[1].index
!= order
)
193 bad_page(__FUNCTION__
, page
);
195 for (i
= 0; i
< nr_pages
; i
++) {
196 struct page
*p
= page
+ i
;
198 if (!PageCompound(p
))
199 bad_page(__FUNCTION__
, page
);
200 if (page_private(p
) != (unsigned long)page
)
201 bad_page(__FUNCTION__
, page
);
202 ClearPageCompound(p
);
205 #endif /* CONFIG_HUGETLB_PAGE */
208 * function for dealing with page's order in buddy system.
209 * zone->lock is already acquired when we use these.
210 * So, we don't need atomic page->flags operations here.
212 static inline unsigned long page_order(struct page
*page
) {
213 return page_private(page
);
216 static inline void set_page_order(struct page
*page
, int order
) {
217 set_page_private(page
, order
);
218 __SetPagePrivate(page
);
221 static inline void rmv_page_order(struct page
*page
)
223 __ClearPagePrivate(page
);
224 set_page_private(page
, 0);
228 * Locate the struct page for both the matching buddy in our
229 * pair (buddy1) and the combined O(n+1) page they form (page).
231 * 1) Any buddy B1 will have an order O twin B2 which satisfies
232 * the following equation:
234 * For example, if the starting buddy (buddy2) is #8 its order
236 * B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10
238 * 2) Any buddy B will have an order O+1 parent P which
239 * satisfies the following equation:
242 * Assumption: *_mem_map is contigious at least up to MAX_ORDER
244 static inline struct page
*
245 __page_find_buddy(struct page
*page
, unsigned long page_idx
, unsigned int order
)
247 unsigned long buddy_idx
= page_idx
^ (1 << order
);
249 return page
+ (buddy_idx
- page_idx
);
252 static inline unsigned long
253 __find_combined_index(unsigned long page_idx
, unsigned int order
)
255 return (page_idx
& ~(1 << order
));
259 * This function checks whether a page is free && is the buddy
260 * we can do coalesce a page and its buddy if
261 * (a) the buddy is free &&
262 * (b) the buddy is on the buddy system &&
263 * (c) a page and its buddy have the same order.
264 * for recording page's order, we use page_private(page) and PG_private.
267 static inline int page_is_buddy(struct page
*page
, int order
)
269 if (PagePrivate(page
) &&
270 (page_order(page
) == order
) &&
271 page_count(page
) == 0)
277 * Freeing function for a buddy system allocator.
279 * The concept of a buddy system is to maintain direct-mapped table
280 * (containing bit values) for memory blocks of various "orders".
281 * The bottom level table contains the map for the smallest allocatable
282 * units of memory (here, pages), and each level above it describes
283 * pairs of units from the levels below, hence, "buddies".
284 * At a high level, all that happens here is marking the table entry
285 * at the bottom level available, and propagating the changes upward
286 * as necessary, plus some accounting needed to play nicely with other
287 * parts of the VM system.
288 * At each level, we keep a list of pages, which are heads of continuous
289 * free pages of length of (1 << order) and marked with PG_Private.Page's
290 * order is recorded in page_private(page) field.
291 * So when we are allocating or freeing one, we can derive the state of the
292 * other. That is, if we allocate a small block, and both were
293 * free, the remainder of the region must be split into blocks.
294 * If a block is freed, and its buddy is also free, then this
295 * triggers coalescing into a block of larger size.
300 static inline void __free_pages_bulk (struct page
*page
,
301 struct zone
*zone
, unsigned int order
)
303 unsigned long page_idx
;
304 int order_size
= 1 << order
;
307 destroy_compound_page(page
, order
);
309 page_idx
= page_to_pfn(page
) & ((1 << MAX_ORDER
) - 1);
311 BUG_ON(page_idx
& (order_size
- 1));
312 BUG_ON(bad_range(zone
, page
));
314 zone
->free_pages
+= order_size
;
315 while (order
< MAX_ORDER
-1) {
316 unsigned long combined_idx
;
317 struct free_area
*area
;
320 combined_idx
= __find_combined_index(page_idx
, order
);
321 buddy
= __page_find_buddy(page
, page_idx
, order
);
323 if (bad_range(zone
, buddy
))
325 if (!page_is_buddy(buddy
, order
))
326 break; /* Move the buddy up one level. */
327 list_del(&buddy
->lru
);
328 area
= zone
->free_area
+ order
;
330 rmv_page_order(buddy
);
331 page
= page
+ (combined_idx
- page_idx
);
332 page_idx
= combined_idx
;
335 set_page_order(page
, order
);
336 list_add(&page
->lru
, &zone
->free_area
[order
].free_list
);
337 zone
->free_area
[order
].nr_free
++;
340 static inline void free_pages_check(const char *function
, struct page
*page
)
342 if ( page_mapcount(page
) ||
343 page
->mapping
!= NULL
||
344 page_count(page
) != 0 ||
355 bad_page(function
, page
);
357 __ClearPageDirty(page
);
361 * Frees a list of pages.
362 * Assumes all pages on list are in same zone, and of same order.
363 * count is the number of pages to free.
365 * If the zone was previously in an "all pages pinned" state then look to
366 * see if this freeing clears that state.
368 * And clear the zone's pages_scanned counter, to hold off the "all pages are
369 * pinned" detection logic.
372 free_pages_bulk(struct zone
*zone
, int count
,
373 struct list_head
*list
, unsigned int order
)
376 struct page
*page
= NULL
;
379 spin_lock_irqsave(&zone
->lock
, flags
);
380 zone
->all_unreclaimable
= 0;
381 zone
->pages_scanned
= 0;
382 while (!list_empty(list
) && count
--) {
383 page
= list_entry(list
->prev
, struct page
, lru
);
384 /* have to delete it as __free_pages_bulk list manipulates */
385 list_del(&page
->lru
);
386 __free_pages_bulk(page
, zone
, order
);
389 spin_unlock_irqrestore(&zone
->lock
, flags
);
393 void __free_pages_ok(struct page
*page
, unsigned int order
)
398 arch_free_page(page
, order
);
400 mod_page_state(pgfree
, 1 << order
);
404 for (i
= 1 ; i
< (1 << order
) ; ++i
)
405 __put_page(page
+ i
);
408 for (i
= 0 ; i
< (1 << order
) ; ++i
)
409 free_pages_check(__FUNCTION__
, page
+ i
);
410 list_add(&page
->lru
, &list
);
411 kernel_map_pages(page
, 1<<order
, 0);
412 free_pages_bulk(page_zone(page
), 1, &list
, order
);
417 * The order of subdivision here is critical for the IO subsystem.
418 * Please do not alter this order without good reasons and regression
419 * testing. Specifically, as large blocks of memory are subdivided,
420 * the order in which smaller blocks are delivered depends on the order
421 * they're subdivided in this function. This is the primary factor
422 * influencing the order in which pages are delivered to the IO
423 * subsystem according to empirical testing, and this is also justified
424 * by considering the behavior of a buddy system containing a single
425 * large block of memory acted on by a series of small allocations.
426 * This behavior is a critical factor in sglist merging's success.
430 static inline struct page
*
431 expand(struct zone
*zone
, struct page
*page
,
432 int low
, int high
, struct free_area
*area
)
434 unsigned long size
= 1 << high
;
440 BUG_ON(bad_range(zone
, &page
[size
]));
441 list_add(&page
[size
].lru
, &area
->free_list
);
443 set_page_order(&page
[size
], high
);
448 void set_page_refs(struct page
*page
, int order
)
451 set_page_count(page
, 1);
456 * We need to reference all the pages for this order, otherwise if
457 * anyone accesses one of the pages with (get/put) it will be freed.
458 * - eg: access_process_vm()
460 for (i
= 0; i
< (1 << order
); i
++)
461 set_page_count(page
+ i
, 1);
462 #endif /* CONFIG_MMU */
466 * This page is about to be returned from the page allocator
468 static void prep_new_page(struct page
*page
, int order
)
470 if ( page_mapcount(page
) ||
471 page
->mapping
!= NULL
||
472 page_count(page
) != 0 ||
484 bad_page(__FUNCTION__
, page
);
486 page
->flags
&= ~(1 << PG_uptodate
| 1 << PG_error
|
487 1 << PG_referenced
| 1 << PG_arch_1
|
488 1 << PG_checked
| 1 << PG_mappedtodisk
);
489 set_page_private(page
, 0);
490 set_page_refs(page
, order
);
491 kernel_map_pages(page
, 1 << order
, 1);
495 * Do the hard work of removing an element from the buddy allocator.
496 * Call me with the zone->lock already held.
498 static struct page
*__rmqueue(struct zone
*zone
, unsigned int order
)
500 struct free_area
* area
;
501 unsigned int current_order
;
504 for (current_order
= order
; current_order
< MAX_ORDER
; ++current_order
) {
505 area
= zone
->free_area
+ current_order
;
506 if (list_empty(&area
->free_list
))
509 page
= list_entry(area
->free_list
.next
, struct page
, lru
);
510 list_del(&page
->lru
);
511 rmv_page_order(page
);
513 zone
->free_pages
-= 1UL << order
;
514 return expand(zone
, page
, order
, current_order
, area
);
521 * Obtain a specified number of elements from the buddy allocator, all under
522 * a single hold of the lock, for efficiency. Add them to the supplied list.
523 * Returns the number of new pages which were placed at *list.
525 static int rmqueue_bulk(struct zone
*zone
, unsigned int order
,
526 unsigned long count
, struct list_head
*list
)
533 spin_lock_irqsave(&zone
->lock
, flags
);
534 for (i
= 0; i
< count
; ++i
) {
535 page
= __rmqueue(zone
, order
);
539 list_add_tail(&page
->lru
, list
);
541 spin_unlock_irqrestore(&zone
->lock
, flags
);
546 /* Called from the slab reaper to drain remote pagesets */
547 void drain_remote_pages(void)
553 local_irq_save(flags
);
554 for_each_zone(zone
) {
555 struct per_cpu_pageset
*pset
;
557 /* Do not drain local pagesets */
558 if (zone
->zone_pgdat
->node_id
== numa_node_id())
561 pset
= zone
->pageset
[smp_processor_id()];
562 for (i
= 0; i
< ARRAY_SIZE(pset
->pcp
); i
++) {
563 struct per_cpu_pages
*pcp
;
567 pcp
->count
-= free_pages_bulk(zone
, pcp
->count
,
571 local_irq_restore(flags
);
575 #if defined(CONFIG_PM) || defined(CONFIG_HOTPLUG_CPU)
576 static void __drain_pages(unsigned int cpu
)
581 for_each_zone(zone
) {
582 struct per_cpu_pageset
*pset
;
584 pset
= zone_pcp(zone
, cpu
);
585 for (i
= 0; i
< ARRAY_SIZE(pset
->pcp
); i
++) {
586 struct per_cpu_pages
*pcp
;
589 pcp
->count
-= free_pages_bulk(zone
, pcp
->count
,
594 #endif /* CONFIG_PM || CONFIG_HOTPLUG_CPU */
598 void mark_free_pages(struct zone
*zone
)
600 unsigned long zone_pfn
, flags
;
602 struct list_head
*curr
;
604 if (!zone
->spanned_pages
)
607 spin_lock_irqsave(&zone
->lock
, flags
);
608 for (zone_pfn
= 0; zone_pfn
< zone
->spanned_pages
; ++zone_pfn
)
609 ClearPageNosaveFree(pfn_to_page(zone_pfn
+ zone
->zone_start_pfn
));
611 for (order
= MAX_ORDER
- 1; order
>= 0; --order
)
612 list_for_each(curr
, &zone
->free_area
[order
].free_list
) {
613 unsigned long start_pfn
, i
;
615 start_pfn
= page_to_pfn(list_entry(curr
, struct page
, lru
));
617 for (i
=0; i
< (1<<order
); i
++)
618 SetPageNosaveFree(pfn_to_page(start_pfn
+i
));
620 spin_unlock_irqrestore(&zone
->lock
, flags
);
624 * Spill all of this CPU's per-cpu pages back into the buddy allocator.
626 void drain_local_pages(void)
630 local_irq_save(flags
);
631 __drain_pages(smp_processor_id());
632 local_irq_restore(flags
);
634 #endif /* CONFIG_PM */
636 static void zone_statistics(struct zonelist
*zonelist
, struct zone
*z
)
641 pg_data_t
*pg
= z
->zone_pgdat
;
642 pg_data_t
*orig
= zonelist
->zones
[0]->zone_pgdat
;
643 struct per_cpu_pageset
*p
;
645 local_irq_save(flags
);
646 cpu
= smp_processor_id();
652 zone_pcp(zonelist
->zones
[0], cpu
)->numa_foreign
++;
654 if (pg
== NODE_DATA(numa_node_id()))
658 local_irq_restore(flags
);
663 * Free a 0-order page
665 static void FASTCALL(free_hot_cold_page(struct page
*page
, int cold
));
666 static void fastcall
free_hot_cold_page(struct page
*page
, int cold
)
668 struct zone
*zone
= page_zone(page
);
669 struct per_cpu_pages
*pcp
;
672 arch_free_page(page
, 0);
674 kernel_map_pages(page
, 1, 0);
675 inc_page_state(pgfree
);
677 page
->mapping
= NULL
;
678 free_pages_check(__FUNCTION__
, page
);
679 pcp
= &zone_pcp(zone
, get_cpu())->pcp
[cold
];
680 local_irq_save(flags
);
681 list_add(&page
->lru
, &pcp
->list
);
683 if (pcp
->count
>= pcp
->high
)
684 pcp
->count
-= free_pages_bulk(zone
, pcp
->batch
, &pcp
->list
, 0);
685 local_irq_restore(flags
);
689 void fastcall
free_hot_page(struct page
*page
)
691 free_hot_cold_page(page
, 0);
694 void fastcall
free_cold_page(struct page
*page
)
696 free_hot_cold_page(page
, 1);
699 static inline void prep_zero_page(struct page
*page
, int order
, gfp_t gfp_flags
)
703 BUG_ON((gfp_flags
& (__GFP_WAIT
| __GFP_HIGHMEM
)) == __GFP_HIGHMEM
);
704 for(i
= 0; i
< (1 << order
); i
++)
705 clear_highpage(page
+ i
);
709 * Really, prep_compound_page() should be called from __rmqueue_bulk(). But
710 * we cheat by calling it from here, in the order > 0 path. Saves a branch
714 buffered_rmqueue(struct zone
*zone
, int order
, gfp_t gfp_flags
)
717 struct page
*page
= NULL
;
718 int cold
= !!(gfp_flags
& __GFP_COLD
);
721 struct per_cpu_pages
*pcp
;
723 pcp
= &zone_pcp(zone
, get_cpu())->pcp
[cold
];
724 local_irq_save(flags
);
725 if (pcp
->count
<= pcp
->low
)
726 pcp
->count
+= rmqueue_bulk(zone
, 0,
727 pcp
->batch
, &pcp
->list
);
729 page
= list_entry(pcp
->list
.next
, struct page
, lru
);
730 list_del(&page
->lru
);
733 local_irq_restore(flags
);
736 spin_lock_irqsave(&zone
->lock
, flags
);
737 page
= __rmqueue(zone
, order
);
738 spin_unlock_irqrestore(&zone
->lock
, flags
);
742 BUG_ON(bad_range(zone
, page
));
743 mod_page_state_zone(zone
, pgalloc
, 1 << order
);
744 prep_new_page(page
, order
);
746 if (gfp_flags
& __GFP_ZERO
)
747 prep_zero_page(page
, order
, gfp_flags
);
749 if (order
&& (gfp_flags
& __GFP_COMP
))
750 prep_compound_page(page
, order
);
755 #define ALLOC_NO_WATERMARKS 0x01 /* don't check watermarks at all */
756 #define ALLOC_HARDER 0x02 /* try to alloc harder */
757 #define ALLOC_HIGH 0x04 /* __GFP_HIGH set */
758 #define ALLOC_CPUSET 0x08 /* check for correct cpuset */
761 * Return 1 if free pages are above 'mark'. This takes into account the order
764 int zone_watermark_ok(struct zone
*z
, int order
, unsigned long mark
,
765 int classzone_idx
, int alloc_flags
)
767 /* free_pages my go negative - that's OK */
768 long min
= mark
, free_pages
= z
->free_pages
- (1 << order
) + 1;
771 if (alloc_flags
& ALLOC_HIGH
)
773 if (alloc_flags
& ALLOC_HARDER
)
776 if (free_pages
<= min
+ z
->lowmem_reserve
[classzone_idx
])
778 for (o
= 0; o
< order
; o
++) {
779 /* At the next order, this order's pages become unavailable */
780 free_pages
-= z
->free_area
[o
].nr_free
<< o
;
782 /* Require fewer higher order pages to be free */
785 if (free_pages
<= min
)
792 * get_page_from_freeliest goes through the zonelist trying to allocate
796 get_page_from_freelist(gfp_t gfp_mask
, unsigned int order
,
797 struct zonelist
*zonelist
, int alloc_flags
)
799 struct zone
**z
= zonelist
->zones
;
800 struct page
*page
= NULL
;
801 int classzone_idx
= zone_idx(*z
);
804 * Go through the zonelist once, looking for a zone with enough free.
805 * See also cpuset_zone_allowed() comment in kernel/cpuset.c.
808 if ((alloc_flags
& ALLOC_CPUSET
) &&
809 !cpuset_zone_allowed(*z
, gfp_mask
))
812 if (!(alloc_flags
& ALLOC_NO_WATERMARKS
)) {
813 if (!zone_watermark_ok(*z
, order
, (*z
)->pages_low
,
814 classzone_idx
, alloc_flags
))
818 page
= buffered_rmqueue(*z
, order
, gfp_mask
);
820 zone_statistics(zonelist
, *z
);
823 } while (*(++z
) != NULL
);
828 * This is the 'heart' of the zoned buddy allocator.
830 struct page
* fastcall
831 __alloc_pages(gfp_t gfp_mask
, unsigned int order
,
832 struct zonelist
*zonelist
)
834 const gfp_t wait
= gfp_mask
& __GFP_WAIT
;
837 struct reclaim_state reclaim_state
;
838 struct task_struct
*p
= current
;
841 int did_some_progress
;
843 might_sleep_if(wait
);
845 z
= zonelist
->zones
; /* the list of zones suitable for gfp_mask */
847 if (unlikely(*z
== NULL
)) {
848 /* Should this ever happen?? */
852 page
= get_page_from_freelist(gfp_mask
|__GFP_HARDWALL
, order
,
853 zonelist
, ALLOC_CPUSET
);
858 wakeup_kswapd(*z
, order
);
862 * OK, we're below the kswapd watermark and have kicked background
863 * reclaim. Now things get more complex, so set up alloc_flags according
864 * to how we want to proceed.
866 * The caller may dip into page reserves a bit more if the caller
867 * cannot run direct reclaim, or if the caller has realtime scheduling
871 if ((unlikely(rt_task(p
)) && !in_interrupt()) || !wait
)
872 alloc_flags
|= ALLOC_HARDER
;
873 if (gfp_mask
& __GFP_HIGH
)
874 alloc_flags
|= ALLOC_HIGH
;
876 alloc_flags
|= ALLOC_CPUSET
;
879 * Go through the zonelist again. Let __GFP_HIGH and allocations
880 * coming from realtime tasks go deeper into reserves.
882 * This is the last chance, in general, before the goto nopage.
883 * Ignore cpuset if GFP_ATOMIC (!wait) rather than fail alloc.
884 * See also cpuset_zone_allowed() comment in kernel/cpuset.c.
886 page
= get_page_from_freelist(gfp_mask
, order
, zonelist
, alloc_flags
);
890 /* This allocation should allow future memory freeing. */
892 if (((p
->flags
& PF_MEMALLOC
) || unlikely(test_thread_flag(TIF_MEMDIE
)))
893 && !in_interrupt()) {
894 if (!(gfp_mask
& __GFP_NOMEMALLOC
)) {
896 /* go through the zonelist yet again, ignoring mins */
897 page
= get_page_from_freelist(gfp_mask
, order
,
898 zonelist
, ALLOC_NO_WATERMARKS
|ALLOC_CPUSET
);
901 if (gfp_mask
& __GFP_NOFAIL
) {
902 blk_congestion_wait(WRITE
, HZ
/50);
909 /* Atomic allocations - we can't balance anything */
916 /* We now go into synchronous reclaim */
917 p
->flags
|= PF_MEMALLOC
;
918 reclaim_state
.reclaimed_slab
= 0;
919 p
->reclaim_state
= &reclaim_state
;
921 did_some_progress
= try_to_free_pages(zonelist
->zones
, gfp_mask
);
923 p
->reclaim_state
= NULL
;
924 p
->flags
&= ~PF_MEMALLOC
;
928 if (likely(did_some_progress
)) {
929 page
= get_page_from_freelist(gfp_mask
, order
,
930 zonelist
, alloc_flags
);
933 } else if ((gfp_mask
& __GFP_FS
) && !(gfp_mask
& __GFP_NORETRY
)) {
935 * Go through the zonelist yet one more time, keep
936 * very high watermark here, this is only to catch
937 * a parallel oom killing, we must fail if we're still
938 * under heavy pressure.
940 page
= get_page_from_freelist(gfp_mask
|__GFP_HARDWALL
, order
,
941 zonelist
, ALLOC_CPUSET
);
945 out_of_memory(gfp_mask
, order
);
950 * Don't let big-order allocations loop unless the caller explicitly
951 * requests that. Wait for some write requests to complete then retry.
953 * In this implementation, __GFP_REPEAT means __GFP_NOFAIL for order
954 * <= 3, but that may not be true in other implementations.
957 if (!(gfp_mask
& __GFP_NORETRY
)) {
958 if ((order
<= 3) || (gfp_mask
& __GFP_REPEAT
))
960 if (gfp_mask
& __GFP_NOFAIL
)
964 blk_congestion_wait(WRITE
, HZ
/50);
969 if (!(gfp_mask
& __GFP_NOWARN
) && printk_ratelimit()) {
970 printk(KERN_WARNING
"%s: page allocation failure."
971 " order:%d, mode:0x%x\n",
972 p
->comm
, order
, gfp_mask
);
980 EXPORT_SYMBOL(__alloc_pages
);
983 * Common helper functions.
985 fastcall
unsigned long __get_free_pages(gfp_t gfp_mask
, unsigned int order
)
988 page
= alloc_pages(gfp_mask
, order
);
991 return (unsigned long) page_address(page
);
994 EXPORT_SYMBOL(__get_free_pages
);
996 fastcall
unsigned long get_zeroed_page(gfp_t gfp_mask
)
1001 * get_zeroed_page() returns a 32-bit address, which cannot represent
1004 BUG_ON((gfp_mask
& __GFP_HIGHMEM
) != 0);
1006 page
= alloc_pages(gfp_mask
| __GFP_ZERO
, 0);
1008 return (unsigned long) page_address(page
);
1012 EXPORT_SYMBOL(get_zeroed_page
);
1014 void __pagevec_free(struct pagevec
*pvec
)
1016 int i
= pagevec_count(pvec
);
1019 free_hot_cold_page(pvec
->pages
[i
], pvec
->cold
);
1022 fastcall
void __free_pages(struct page
*page
, unsigned int order
)
1024 if (put_page_testzero(page
)) {
1026 free_hot_page(page
);
1028 __free_pages_ok(page
, order
);
1032 EXPORT_SYMBOL(__free_pages
);
1034 fastcall
void free_pages(unsigned long addr
, unsigned int order
)
1037 BUG_ON(!virt_addr_valid((void *)addr
));
1038 __free_pages(virt_to_page((void *)addr
), order
);
1042 EXPORT_SYMBOL(free_pages
);
1045 * Total amount of free (allocatable) RAM:
1047 unsigned int nr_free_pages(void)
1049 unsigned int sum
= 0;
1053 sum
+= zone
->free_pages
;
1058 EXPORT_SYMBOL(nr_free_pages
);
1061 unsigned int nr_free_pages_pgdat(pg_data_t
*pgdat
)
1063 unsigned int i
, sum
= 0;
1065 for (i
= 0; i
< MAX_NR_ZONES
; i
++)
1066 sum
+= pgdat
->node_zones
[i
].free_pages
;
1072 static unsigned int nr_free_zone_pages(int offset
)
1074 /* Just pick one node, since fallback list is circular */
1075 pg_data_t
*pgdat
= NODE_DATA(numa_node_id());
1076 unsigned int sum
= 0;
1078 struct zonelist
*zonelist
= pgdat
->node_zonelists
+ offset
;
1079 struct zone
**zonep
= zonelist
->zones
;
1082 for (zone
= *zonep
++; zone
; zone
= *zonep
++) {
1083 unsigned long size
= zone
->present_pages
;
1084 unsigned long high
= zone
->pages_high
;
1093 * Amount of free RAM allocatable within ZONE_DMA and ZONE_NORMAL
1095 unsigned int nr_free_buffer_pages(void)
1097 return nr_free_zone_pages(gfp_zone(GFP_USER
));
1101 * Amount of free RAM allocatable within all zones
1103 unsigned int nr_free_pagecache_pages(void)
1105 return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER
));
1108 #ifdef CONFIG_HIGHMEM
1109 unsigned int nr_free_highpages (void)
1112 unsigned int pages
= 0;
1114 for_each_pgdat(pgdat
)
1115 pages
+= pgdat
->node_zones
[ZONE_HIGHMEM
].free_pages
;
1122 static void show_node(struct zone
*zone
)
1124 printk("Node %d ", zone
->zone_pgdat
->node_id
);
1127 #define show_node(zone) do { } while (0)
1131 * Accumulate the page_state information across all CPUs.
1132 * The result is unavoidably approximate - it can change
1133 * during and after execution of this function.
1135 static DEFINE_PER_CPU(struct page_state
, page_states
) = {0};
1137 atomic_t nr_pagecache
= ATOMIC_INIT(0);
1138 EXPORT_SYMBOL(nr_pagecache
);
1140 DEFINE_PER_CPU(long, nr_pagecache_local
) = 0;
1143 void __get_page_state(struct page_state
*ret
, int nr
, cpumask_t
*cpumask
)
1147 memset(ret
, 0, sizeof(*ret
));
1148 cpus_and(*cpumask
, *cpumask
, cpu_online_map
);
1150 cpu
= first_cpu(*cpumask
);
1151 while (cpu
< NR_CPUS
) {
1152 unsigned long *in
, *out
, off
;
1154 in
= (unsigned long *)&per_cpu(page_states
, cpu
);
1156 cpu
= next_cpu(cpu
, *cpumask
);
1159 prefetch(&per_cpu(page_states
, cpu
));
1161 out
= (unsigned long *)ret
;
1162 for (off
= 0; off
< nr
; off
++)
1167 void get_page_state_node(struct page_state
*ret
, int node
)
1170 cpumask_t mask
= node_to_cpumask(node
);
1172 nr
= offsetof(struct page_state
, GET_PAGE_STATE_LAST
);
1173 nr
/= sizeof(unsigned long);
1175 __get_page_state(ret
, nr
+1, &mask
);
1178 void get_page_state(struct page_state
*ret
)
1181 cpumask_t mask
= CPU_MASK_ALL
;
1183 nr
= offsetof(struct page_state
, GET_PAGE_STATE_LAST
);
1184 nr
/= sizeof(unsigned long);
1186 __get_page_state(ret
, nr
+ 1, &mask
);
1189 void get_full_page_state(struct page_state
*ret
)
1191 cpumask_t mask
= CPU_MASK_ALL
;
1193 __get_page_state(ret
, sizeof(*ret
) / sizeof(unsigned long), &mask
);
1196 unsigned long __read_page_state(unsigned long offset
)
1198 unsigned long ret
= 0;
1201 for_each_online_cpu(cpu
) {
1204 in
= (unsigned long)&per_cpu(page_states
, cpu
) + offset
;
1205 ret
+= *((unsigned long *)in
);
1210 void __mod_page_state(unsigned long offset
, unsigned long delta
)
1212 unsigned long flags
;
1215 local_irq_save(flags
);
1216 ptr
= &__get_cpu_var(page_states
);
1217 *(unsigned long*)(ptr
+ offset
) += delta
;
1218 local_irq_restore(flags
);
1221 EXPORT_SYMBOL(__mod_page_state
);
1223 void __get_zone_counts(unsigned long *active
, unsigned long *inactive
,
1224 unsigned long *free
, struct pglist_data
*pgdat
)
1226 struct zone
*zones
= pgdat
->node_zones
;
1232 for (i
= 0; i
< MAX_NR_ZONES
; i
++) {
1233 *active
+= zones
[i
].nr_active
;
1234 *inactive
+= zones
[i
].nr_inactive
;
1235 *free
+= zones
[i
].free_pages
;
1239 void get_zone_counts(unsigned long *active
,
1240 unsigned long *inactive
, unsigned long *free
)
1242 struct pglist_data
*pgdat
;
1247 for_each_pgdat(pgdat
) {
1248 unsigned long l
, m
, n
;
1249 __get_zone_counts(&l
, &m
, &n
, pgdat
);
1256 void si_meminfo(struct sysinfo
*val
)
1258 val
->totalram
= totalram_pages
;
1260 val
->freeram
= nr_free_pages();
1261 val
->bufferram
= nr_blockdev_pages();
1262 #ifdef CONFIG_HIGHMEM
1263 val
->totalhigh
= totalhigh_pages
;
1264 val
->freehigh
= nr_free_highpages();
1269 val
->mem_unit
= PAGE_SIZE
;
1272 EXPORT_SYMBOL(si_meminfo
);
1275 void si_meminfo_node(struct sysinfo
*val
, int nid
)
1277 pg_data_t
*pgdat
= NODE_DATA(nid
);
1279 val
->totalram
= pgdat
->node_present_pages
;
1280 val
->freeram
= nr_free_pages_pgdat(pgdat
);
1281 val
->totalhigh
= pgdat
->node_zones
[ZONE_HIGHMEM
].present_pages
;
1282 val
->freehigh
= pgdat
->node_zones
[ZONE_HIGHMEM
].free_pages
;
1283 val
->mem_unit
= PAGE_SIZE
;
1287 #define K(x) ((x) << (PAGE_SHIFT-10))
1290 * Show free area list (used inside shift_scroll-lock stuff)
1291 * We also calculate the percentage fragmentation. We do this by counting the
1292 * memory on each free list with the exception of the first item on the list.
1294 void show_free_areas(void)
1296 struct page_state ps
;
1297 int cpu
, temperature
;
1298 unsigned long active
;
1299 unsigned long inactive
;
1303 for_each_zone(zone
) {
1305 printk("%s per-cpu:", zone
->name
);
1307 if (!zone
->present_pages
) {
1313 for_each_online_cpu(cpu
) {
1314 struct per_cpu_pageset
*pageset
;
1316 pageset
= zone_pcp(zone
, cpu
);
1318 for (temperature
= 0; temperature
< 2; temperature
++)
1319 printk("cpu %d %s: low %d, high %d, batch %d used:%d\n",
1321 temperature
? "cold" : "hot",
1322 pageset
->pcp
[temperature
].low
,
1323 pageset
->pcp
[temperature
].high
,
1324 pageset
->pcp
[temperature
].batch
,
1325 pageset
->pcp
[temperature
].count
);
1329 get_page_state(&ps
);
1330 get_zone_counts(&active
, &inactive
, &free
);
1332 printk("Free pages: %11ukB (%ukB HighMem)\n",
1334 K(nr_free_highpages()));
1336 printk("Active:%lu inactive:%lu dirty:%lu writeback:%lu "
1337 "unstable:%lu free:%u slab:%lu mapped:%lu pagetables:%lu\n",
1346 ps
.nr_page_table_pages
);
1348 for_each_zone(zone
) {
1360 " pages_scanned:%lu"
1361 " all_unreclaimable? %s"
1364 K(zone
->free_pages
),
1367 K(zone
->pages_high
),
1369 K(zone
->nr_inactive
),
1370 K(zone
->present_pages
),
1371 zone
->pages_scanned
,
1372 (zone
->all_unreclaimable
? "yes" : "no")
1374 printk("lowmem_reserve[]:");
1375 for (i
= 0; i
< MAX_NR_ZONES
; i
++)
1376 printk(" %lu", zone
->lowmem_reserve
[i
]);
1380 for_each_zone(zone
) {
1381 unsigned long nr
, flags
, order
, total
= 0;
1384 printk("%s: ", zone
->name
);
1385 if (!zone
->present_pages
) {
1390 spin_lock_irqsave(&zone
->lock
, flags
);
1391 for (order
= 0; order
< MAX_ORDER
; order
++) {
1392 nr
= zone
->free_area
[order
].nr_free
;
1393 total
+= nr
<< order
;
1394 printk("%lu*%lukB ", nr
, K(1UL) << order
);
1396 spin_unlock_irqrestore(&zone
->lock
, flags
);
1397 printk("= %lukB\n", K(total
));
1400 show_swap_cache_info();
1404 * Builds allocation fallback zone lists.
1406 static int __init
build_zonelists_node(pg_data_t
*pgdat
, struct zonelist
*zonelist
, int j
, int k
)
1413 zone
= pgdat
->node_zones
+ ZONE_HIGHMEM
;
1414 if (zone
->present_pages
) {
1415 #ifndef CONFIG_HIGHMEM
1418 zonelist
->zones
[j
++] = zone
;
1421 zone
= pgdat
->node_zones
+ ZONE_NORMAL
;
1422 if (zone
->present_pages
)
1423 zonelist
->zones
[j
++] = zone
;
1425 zone
= pgdat
->node_zones
+ ZONE_DMA
;
1426 if (zone
->present_pages
)
1427 zonelist
->zones
[j
++] = zone
;
1433 static inline int highest_zone(int zone_bits
)
1435 int res
= ZONE_NORMAL
;
1436 if (zone_bits
& (__force
int)__GFP_HIGHMEM
)
1438 if (zone_bits
& (__force
int)__GFP_DMA
)
1444 #define MAX_NODE_LOAD (num_online_nodes())
1445 static int __initdata node_load
[MAX_NUMNODES
];
1447 * find_next_best_node - find the next node that should appear in a given node's fallback list
1448 * @node: node whose fallback list we're appending
1449 * @used_node_mask: nodemask_t of already used nodes
1451 * We use a number of factors to determine which is the next node that should
1452 * appear on a given node's fallback list. The node should not have appeared
1453 * already in @node's fallback list, and it should be the next closest node
1454 * according to the distance array (which contains arbitrary distance values
1455 * from each node to each node in the system), and should also prefer nodes
1456 * with no CPUs, since presumably they'll have very little allocation pressure
1457 * on them otherwise.
1458 * It returns -1 if no node is found.
1460 static int __init
find_next_best_node(int node
, nodemask_t
*used_node_mask
)
1463 int min_val
= INT_MAX
;
1466 for_each_online_node(i
) {
1469 /* Start from local node */
1470 n
= (node
+i
) % num_online_nodes();
1472 /* Don't want a node to appear more than once */
1473 if (node_isset(n
, *used_node_mask
))
1476 /* Use the local node if we haven't already */
1477 if (!node_isset(node
, *used_node_mask
)) {
1482 /* Use the distance array to find the distance */
1483 val
= node_distance(node
, n
);
1485 /* Give preference to headless and unused nodes */
1486 tmp
= node_to_cpumask(n
);
1487 if (!cpus_empty(tmp
))
1488 val
+= PENALTY_FOR_NODE_WITH_CPUS
;
1490 /* Slight preference for less loaded node */
1491 val
*= (MAX_NODE_LOAD
*MAX_NUMNODES
);
1492 val
+= node_load
[n
];
1494 if (val
< min_val
) {
1501 node_set(best_node
, *used_node_mask
);
1506 static void __init
build_zonelists(pg_data_t
*pgdat
)
1508 int i
, j
, k
, node
, local_node
;
1509 int prev_node
, load
;
1510 struct zonelist
*zonelist
;
1511 nodemask_t used_mask
;
1513 /* initialize zonelists */
1514 for (i
= 0; i
< GFP_ZONETYPES
; i
++) {
1515 zonelist
= pgdat
->node_zonelists
+ i
;
1516 zonelist
->zones
[0] = NULL
;
1519 /* NUMA-aware ordering of nodes */
1520 local_node
= pgdat
->node_id
;
1521 load
= num_online_nodes();
1522 prev_node
= local_node
;
1523 nodes_clear(used_mask
);
1524 while ((node
= find_next_best_node(local_node
, &used_mask
)) >= 0) {
1526 * We don't want to pressure a particular node.
1527 * So adding penalty to the first node in same
1528 * distance group to make it round-robin.
1530 if (node_distance(local_node
, node
) !=
1531 node_distance(local_node
, prev_node
))
1532 node_load
[node
] += load
;
1535 for (i
= 0; i
< GFP_ZONETYPES
; i
++) {
1536 zonelist
= pgdat
->node_zonelists
+ i
;
1537 for (j
= 0; zonelist
->zones
[j
] != NULL
; j
++);
1539 k
= highest_zone(i
);
1541 j
= build_zonelists_node(NODE_DATA(node
), zonelist
, j
, k
);
1542 zonelist
->zones
[j
] = NULL
;
1547 #else /* CONFIG_NUMA */
1549 static void __init
build_zonelists(pg_data_t
*pgdat
)
1551 int i
, j
, k
, node
, local_node
;
1553 local_node
= pgdat
->node_id
;
1554 for (i
= 0; i
< GFP_ZONETYPES
; i
++) {
1555 struct zonelist
*zonelist
;
1557 zonelist
= pgdat
->node_zonelists
+ i
;
1560 k
= highest_zone(i
);
1561 j
= build_zonelists_node(pgdat
, zonelist
, j
, k
);
1563 * Now we build the zonelist so that it contains the zones
1564 * of all the other nodes.
1565 * We don't want to pressure a particular node, so when
1566 * building the zones for node N, we make sure that the
1567 * zones coming right after the local ones are those from
1568 * node N+1 (modulo N)
1570 for (node
= local_node
+ 1; node
< MAX_NUMNODES
; node
++) {
1571 if (!node_online(node
))
1573 j
= build_zonelists_node(NODE_DATA(node
), zonelist
, j
, k
);
1575 for (node
= 0; node
< local_node
; node
++) {
1576 if (!node_online(node
))
1578 j
= build_zonelists_node(NODE_DATA(node
), zonelist
, j
, k
);
1581 zonelist
->zones
[j
] = NULL
;
1585 #endif /* CONFIG_NUMA */
1587 void __init
build_all_zonelists(void)
1591 for_each_online_node(i
)
1592 build_zonelists(NODE_DATA(i
));
1593 printk("Built %i zonelists\n", num_online_nodes());
1594 cpuset_init_current_mems_allowed();
1598 * Helper functions to size the waitqueue hash table.
1599 * Essentially these want to choose hash table sizes sufficiently
1600 * large so that collisions trying to wait on pages are rare.
1601 * But in fact, the number of active page waitqueues on typical
1602 * systems is ridiculously low, less than 200. So this is even
1603 * conservative, even though it seems large.
1605 * The constant PAGES_PER_WAITQUEUE specifies the ratio of pages to
1606 * waitqueues, i.e. the size of the waitq table given the number of pages.
1608 #define PAGES_PER_WAITQUEUE 256
1610 static inline unsigned long wait_table_size(unsigned long pages
)
1612 unsigned long size
= 1;
1614 pages
/= PAGES_PER_WAITQUEUE
;
1616 while (size
< pages
)
1620 * Once we have dozens or even hundreds of threads sleeping
1621 * on IO we've got bigger problems than wait queue collision.
1622 * Limit the size of the wait table to a reasonable size.
1624 size
= min(size
, 4096UL);
1626 return max(size
, 4UL);
1630 * This is an integer logarithm so that shifts can be used later
1631 * to extract the more random high bits from the multiplicative
1632 * hash function before the remainder is taken.
1634 static inline unsigned long wait_table_bits(unsigned long size
)
1639 #define LONG_ALIGN(x) (((x)+(sizeof(long))-1)&~((sizeof(long))-1))
1641 static void __init
calculate_zone_totalpages(struct pglist_data
*pgdat
,
1642 unsigned long *zones_size
, unsigned long *zholes_size
)
1644 unsigned long realtotalpages
, totalpages
= 0;
1647 for (i
= 0; i
< MAX_NR_ZONES
; i
++)
1648 totalpages
+= zones_size
[i
];
1649 pgdat
->node_spanned_pages
= totalpages
;
1651 realtotalpages
= totalpages
;
1653 for (i
= 0; i
< MAX_NR_ZONES
; i
++)
1654 realtotalpages
-= zholes_size
[i
];
1655 pgdat
->node_present_pages
= realtotalpages
;
1656 printk(KERN_DEBUG
"On node %d totalpages: %lu\n", pgdat
->node_id
, realtotalpages
);
1661 * Initially all pages are reserved - free ones are freed
1662 * up by free_all_bootmem() once the early boot process is
1663 * done. Non-atomic initialization, single-pass.
1665 void __devinit
memmap_init_zone(unsigned long size
, int nid
, unsigned long zone
,
1666 unsigned long start_pfn
)
1669 unsigned long end_pfn
= start_pfn
+ size
;
1672 for (pfn
= start_pfn
; pfn
< end_pfn
; pfn
++, page
++) {
1673 if (!early_pfn_valid(pfn
))
1675 if (!early_pfn_in_nid(pfn
, nid
))
1677 page
= pfn_to_page(pfn
);
1678 set_page_links(page
, zone
, nid
, pfn
);
1679 set_page_count(page
, 1);
1680 reset_page_mapcount(page
);
1681 SetPageReserved(page
);
1682 INIT_LIST_HEAD(&page
->lru
);
1683 #ifdef WANT_PAGE_VIRTUAL
1684 /* The shift won't overflow because ZONE_NORMAL is below 4G. */
1685 if (!is_highmem_idx(zone
))
1686 set_page_address(page
, __va(pfn
<< PAGE_SHIFT
));
1691 void zone_init_free_lists(struct pglist_data
*pgdat
, struct zone
*zone
,
1695 for (order
= 0; order
< MAX_ORDER
; order
++) {
1696 INIT_LIST_HEAD(&zone
->free_area
[order
].free_list
);
1697 zone
->free_area
[order
].nr_free
= 0;
1701 #define ZONETABLE_INDEX(x, zone_nr) ((x << ZONES_SHIFT) | zone_nr)
1702 void zonetable_add(struct zone
*zone
, int nid
, int zid
, unsigned long pfn
,
1705 unsigned long snum
= pfn_to_section_nr(pfn
);
1706 unsigned long end
= pfn_to_section_nr(pfn
+ size
);
1709 zone_table
[ZONETABLE_INDEX(nid
, zid
)] = zone
;
1711 for (; snum
<= end
; snum
++)
1712 zone_table
[ZONETABLE_INDEX(snum
, zid
)] = zone
;
1715 #ifndef __HAVE_ARCH_MEMMAP_INIT
1716 #define memmap_init(size, nid, zone, start_pfn) \
1717 memmap_init_zone((size), (nid), (zone), (start_pfn))
1720 static int __devinit
zone_batchsize(struct zone
*zone
)
1725 * The per-cpu-pages pools are set to around 1000th of the
1726 * size of the zone. But no more than 1/2 of a meg.
1728 * OK, so we don't know how big the cache is. So guess.
1730 batch
= zone
->present_pages
/ 1024;
1731 if (batch
* PAGE_SIZE
> 512 * 1024)
1732 batch
= (512 * 1024) / PAGE_SIZE
;
1733 batch
/= 4; /* We effectively *= 4 below */
1738 * We will be trying to allcoate bigger chunks of contiguous
1739 * memory of the order of fls(batch). This should result in
1740 * better cache coloring.
1742 * A sanity check also to ensure that batch is still in limits.
1744 batch
= (1 << fls(batch
+ batch
/2));
1746 if (fls(batch
) >= (PAGE_SHIFT
+ MAX_ORDER
- 2))
1747 batch
= PAGE_SHIFT
+ ((MAX_ORDER
- 1 - PAGE_SHIFT
)/2);
1752 inline void setup_pageset(struct per_cpu_pageset
*p
, unsigned long batch
)
1754 struct per_cpu_pages
*pcp
;
1756 memset(p
, 0, sizeof(*p
));
1758 pcp
= &p
->pcp
[0]; /* hot */
1761 pcp
->high
= 6 * batch
;
1762 pcp
->batch
= max(1UL, 1 * batch
);
1763 INIT_LIST_HEAD(&pcp
->list
);
1765 pcp
= &p
->pcp
[1]; /* cold*/
1768 pcp
->high
= 2 * batch
;
1769 pcp
->batch
= max(1UL, batch
/2);
1770 INIT_LIST_HEAD(&pcp
->list
);
1775 * Boot pageset table. One per cpu which is going to be used for all
1776 * zones and all nodes. The parameters will be set in such a way
1777 * that an item put on a list will immediately be handed over to
1778 * the buddy list. This is safe since pageset manipulation is done
1779 * with interrupts disabled.
1781 * Some NUMA counter updates may also be caught by the boot pagesets.
1783 * The boot_pagesets must be kept even after bootup is complete for
1784 * unused processors and/or zones. They do play a role for bootstrapping
1785 * hotplugged processors.
1787 * zoneinfo_show() and maybe other functions do
1788 * not check if the processor is online before following the pageset pointer.
1789 * Other parts of the kernel may not check if the zone is available.
1791 static struct per_cpu_pageset
1792 boot_pageset
[NR_CPUS
];
1795 * Dynamically allocate memory for the
1796 * per cpu pageset array in struct zone.
1798 static int __devinit
process_zones(int cpu
)
1800 struct zone
*zone
, *dzone
;
1802 for_each_zone(zone
) {
1804 zone
->pageset
[cpu
] = kmalloc_node(sizeof(struct per_cpu_pageset
),
1805 GFP_KERNEL
, cpu_to_node(cpu
));
1806 if (!zone
->pageset
[cpu
])
1809 setup_pageset(zone
->pageset
[cpu
], zone_batchsize(zone
));
1814 for_each_zone(dzone
) {
1817 kfree(dzone
->pageset
[cpu
]);
1818 dzone
->pageset
[cpu
] = NULL
;
1823 static inline void free_zone_pagesets(int cpu
)
1828 for_each_zone(zone
) {
1829 struct per_cpu_pageset
*pset
= zone_pcp(zone
, cpu
);
1831 zone_pcp(zone
, cpu
) = NULL
;
1837 static int __devinit
pageset_cpuup_callback(struct notifier_block
*nfb
,
1838 unsigned long action
,
1841 int cpu
= (long)hcpu
;
1842 int ret
= NOTIFY_OK
;
1845 case CPU_UP_PREPARE
:
1846 if (process_zones(cpu
))
1849 #ifdef CONFIG_HOTPLUG_CPU
1851 free_zone_pagesets(cpu
);
1860 static struct notifier_block pageset_notifier
=
1861 { &pageset_cpuup_callback
, NULL
, 0 };
1863 void __init
setup_per_cpu_pageset()
1867 /* Initialize per_cpu_pageset for cpu 0.
1868 * A cpuup callback will do this for every cpu
1869 * as it comes online
1871 err
= process_zones(smp_processor_id());
1873 register_cpu_notifier(&pageset_notifier
);
1879 void zone_wait_table_init(struct zone
*zone
, unsigned long zone_size_pages
)
1882 struct pglist_data
*pgdat
= zone
->zone_pgdat
;
1885 * The per-page waitqueue mechanism uses hashed waitqueues
1888 zone
->wait_table_size
= wait_table_size(zone_size_pages
);
1889 zone
->wait_table_bits
= wait_table_bits(zone
->wait_table_size
);
1890 zone
->wait_table
= (wait_queue_head_t
*)
1891 alloc_bootmem_node(pgdat
, zone
->wait_table_size
1892 * sizeof(wait_queue_head_t
));
1894 for(i
= 0; i
< zone
->wait_table_size
; ++i
)
1895 init_waitqueue_head(zone
->wait_table
+ i
);
1898 static __devinit
void zone_pcp_init(struct zone
*zone
)
1901 unsigned long batch
= zone_batchsize(zone
);
1903 for (cpu
= 0; cpu
< NR_CPUS
; cpu
++) {
1905 /* Early boot. Slab allocator not functional yet */
1906 zone
->pageset
[cpu
] = &boot_pageset
[cpu
];
1907 setup_pageset(&boot_pageset
[cpu
],0);
1909 setup_pageset(zone_pcp(zone
,cpu
), batch
);
1912 printk(KERN_DEBUG
" %s zone: %lu pages, LIFO batch:%lu\n",
1913 zone
->name
, zone
->present_pages
, batch
);
1916 static __devinit
void init_currently_empty_zone(struct zone
*zone
,
1917 unsigned long zone_start_pfn
, unsigned long size
)
1919 struct pglist_data
*pgdat
= zone
->zone_pgdat
;
1921 zone_wait_table_init(zone
, size
);
1922 pgdat
->nr_zones
= zone_idx(zone
) + 1;
1924 zone
->zone_mem_map
= pfn_to_page(zone_start_pfn
);
1925 zone
->zone_start_pfn
= zone_start_pfn
;
1927 memmap_init(size
, pgdat
->node_id
, zone_idx(zone
), zone_start_pfn
);
1929 zone_init_free_lists(pgdat
, zone
, zone
->spanned_pages
);
1933 * Set up the zone data structures:
1934 * - mark all pages reserved
1935 * - mark all memory queues empty
1936 * - clear the memory bitmaps
1938 static void __init
free_area_init_core(struct pglist_data
*pgdat
,
1939 unsigned long *zones_size
, unsigned long *zholes_size
)
1942 int nid
= pgdat
->node_id
;
1943 unsigned long zone_start_pfn
= pgdat
->node_start_pfn
;
1945 pgdat_resize_init(pgdat
);
1946 pgdat
->nr_zones
= 0;
1947 init_waitqueue_head(&pgdat
->kswapd_wait
);
1948 pgdat
->kswapd_max_order
= 0;
1950 for (j
= 0; j
< MAX_NR_ZONES
; j
++) {
1951 struct zone
*zone
= pgdat
->node_zones
+ j
;
1952 unsigned long size
, realsize
;
1954 realsize
= size
= zones_size
[j
];
1956 realsize
-= zholes_size
[j
];
1958 if (j
== ZONE_DMA
|| j
== ZONE_NORMAL
)
1959 nr_kernel_pages
+= realsize
;
1960 nr_all_pages
+= realsize
;
1962 zone
->spanned_pages
= size
;
1963 zone
->present_pages
= realsize
;
1964 zone
->name
= zone_names
[j
];
1965 spin_lock_init(&zone
->lock
);
1966 spin_lock_init(&zone
->lru_lock
);
1967 zone_seqlock_init(zone
);
1968 zone
->zone_pgdat
= pgdat
;
1969 zone
->free_pages
= 0;
1971 zone
->temp_priority
= zone
->prev_priority
= DEF_PRIORITY
;
1973 zone_pcp_init(zone
);
1974 INIT_LIST_HEAD(&zone
->active_list
);
1975 INIT_LIST_HEAD(&zone
->inactive_list
);
1976 zone
->nr_scan_active
= 0;
1977 zone
->nr_scan_inactive
= 0;
1978 zone
->nr_active
= 0;
1979 zone
->nr_inactive
= 0;
1980 atomic_set(&zone
->reclaim_in_progress
, 0);
1984 zonetable_add(zone
, nid
, j
, zone_start_pfn
, size
);
1985 init_currently_empty_zone(zone
, zone_start_pfn
, size
);
1986 zone_start_pfn
+= size
;
1990 static void __init
alloc_node_mem_map(struct pglist_data
*pgdat
)
1992 /* Skip empty nodes */
1993 if (!pgdat
->node_spanned_pages
)
1996 #ifdef CONFIG_FLAT_NODE_MEM_MAP
1997 /* ia64 gets its own node_mem_map, before this, without bootmem */
1998 if (!pgdat
->node_mem_map
) {
2002 size
= (pgdat
->node_spanned_pages
+ 1) * sizeof(struct page
);
2003 map
= alloc_remap(pgdat
->node_id
, size
);
2005 map
= alloc_bootmem_node(pgdat
, size
);
2006 pgdat
->node_mem_map
= map
;
2008 #ifdef CONFIG_FLATMEM
2010 * With no DISCONTIG, the global mem_map is just set as node 0's
2012 if (pgdat
== NODE_DATA(0))
2013 mem_map
= NODE_DATA(0)->node_mem_map
;
2015 #endif /* CONFIG_FLAT_NODE_MEM_MAP */
2018 void __init
free_area_init_node(int nid
, struct pglist_data
*pgdat
,
2019 unsigned long *zones_size
, unsigned long node_start_pfn
,
2020 unsigned long *zholes_size
)
2022 pgdat
->node_id
= nid
;
2023 pgdat
->node_start_pfn
= node_start_pfn
;
2024 calculate_zone_totalpages(pgdat
, zones_size
, zholes_size
);
2026 alloc_node_mem_map(pgdat
);
2028 free_area_init_core(pgdat
, zones_size
, zholes_size
);
2031 #ifndef CONFIG_NEED_MULTIPLE_NODES
2032 static bootmem_data_t contig_bootmem_data
;
2033 struct pglist_data contig_page_data
= { .bdata
= &contig_bootmem_data
};
2035 EXPORT_SYMBOL(contig_page_data
);
2038 void __init
free_area_init(unsigned long *zones_size
)
2040 free_area_init_node(0, NODE_DATA(0), zones_size
,
2041 __pa(PAGE_OFFSET
) >> PAGE_SHIFT
, NULL
);
2044 #ifdef CONFIG_PROC_FS
2046 #include <linux/seq_file.h>
2048 static void *frag_start(struct seq_file
*m
, loff_t
*pos
)
2053 for (pgdat
= pgdat_list
; pgdat
&& node
; pgdat
= pgdat
->pgdat_next
)
2059 static void *frag_next(struct seq_file
*m
, void *arg
, loff_t
*pos
)
2061 pg_data_t
*pgdat
= (pg_data_t
*)arg
;
2064 return pgdat
->pgdat_next
;
2067 static void frag_stop(struct seq_file
*m
, void *arg
)
2072 * This walks the free areas for each zone.
2074 static int frag_show(struct seq_file
*m
, void *arg
)
2076 pg_data_t
*pgdat
= (pg_data_t
*)arg
;
2078 struct zone
*node_zones
= pgdat
->node_zones
;
2079 unsigned long flags
;
2082 for (zone
= node_zones
; zone
- node_zones
< MAX_NR_ZONES
; ++zone
) {
2083 if (!zone
->present_pages
)
2086 spin_lock_irqsave(&zone
->lock
, flags
);
2087 seq_printf(m
, "Node %d, zone %8s ", pgdat
->node_id
, zone
->name
);
2088 for (order
= 0; order
< MAX_ORDER
; ++order
)
2089 seq_printf(m
, "%6lu ", zone
->free_area
[order
].nr_free
);
2090 spin_unlock_irqrestore(&zone
->lock
, flags
);
2096 struct seq_operations fragmentation_op
= {
2097 .start
= frag_start
,
2104 * Output information about zones in @pgdat.
2106 static int zoneinfo_show(struct seq_file
*m
, void *arg
)
2108 pg_data_t
*pgdat
= arg
;
2110 struct zone
*node_zones
= pgdat
->node_zones
;
2111 unsigned long flags
;
2113 for (zone
= node_zones
; zone
- node_zones
< MAX_NR_ZONES
; zone
++) {
2116 if (!zone
->present_pages
)
2119 spin_lock_irqsave(&zone
->lock
, flags
);
2120 seq_printf(m
, "Node %d, zone %8s", pgdat
->node_id
, zone
->name
);
2128 "\n scanned %lu (a: %lu i: %lu)"
2137 zone
->pages_scanned
,
2138 zone
->nr_scan_active
, zone
->nr_scan_inactive
,
2139 zone
->spanned_pages
,
2140 zone
->present_pages
);
2142 "\n protection: (%lu",
2143 zone
->lowmem_reserve
[0]);
2144 for (i
= 1; i
< ARRAY_SIZE(zone
->lowmem_reserve
); i
++)
2145 seq_printf(m
, ", %lu", zone
->lowmem_reserve
[i
]);
2149 for (i
= 0; i
< ARRAY_SIZE(zone
->pageset
); i
++) {
2150 struct per_cpu_pageset
*pageset
;
2153 pageset
= zone_pcp(zone
, i
);
2154 for (j
= 0; j
< ARRAY_SIZE(pageset
->pcp
); j
++) {
2155 if (pageset
->pcp
[j
].count
)
2158 if (j
== ARRAY_SIZE(pageset
->pcp
))
2160 for (j
= 0; j
< ARRAY_SIZE(pageset
->pcp
); j
++) {
2162 "\n cpu: %i pcp: %i"
2168 pageset
->pcp
[j
].count
,
2169 pageset
->pcp
[j
].low
,
2170 pageset
->pcp
[j
].high
,
2171 pageset
->pcp
[j
].batch
);
2177 "\n numa_foreign: %lu"
2178 "\n interleave_hit: %lu"
2179 "\n local_node: %lu"
2180 "\n other_node: %lu",
2183 pageset
->numa_foreign
,
2184 pageset
->interleave_hit
,
2185 pageset
->local_node
,
2186 pageset
->other_node
);
2190 "\n all_unreclaimable: %u"
2191 "\n prev_priority: %i"
2192 "\n temp_priority: %i"
2193 "\n start_pfn: %lu",
2194 zone
->all_unreclaimable
,
2195 zone
->prev_priority
,
2196 zone
->temp_priority
,
2197 zone
->zone_start_pfn
);
2198 spin_unlock_irqrestore(&zone
->lock
, flags
);
2204 struct seq_operations zoneinfo_op
= {
2205 .start
= frag_start
, /* iterate over all zones. The same as in
2209 .show
= zoneinfo_show
,
2212 static char *vmstat_text
[] = {
2216 "nr_page_table_pages",
2241 "pgscan_kswapd_high",
2242 "pgscan_kswapd_normal",
2244 "pgscan_kswapd_dma",
2245 "pgscan_direct_high",
2246 "pgscan_direct_normal",
2247 "pgscan_direct_dma",
2252 "kswapd_inodesteal",
2260 static void *vmstat_start(struct seq_file
*m
, loff_t
*pos
)
2262 struct page_state
*ps
;
2264 if (*pos
>= ARRAY_SIZE(vmstat_text
))
2267 ps
= kmalloc(sizeof(*ps
), GFP_KERNEL
);
2270 return ERR_PTR(-ENOMEM
);
2271 get_full_page_state(ps
);
2272 ps
->pgpgin
/= 2; /* sectors -> kbytes */
2274 return (unsigned long *)ps
+ *pos
;
2277 static void *vmstat_next(struct seq_file
*m
, void *arg
, loff_t
*pos
)
2280 if (*pos
>= ARRAY_SIZE(vmstat_text
))
2282 return (unsigned long *)m
->private + *pos
;
2285 static int vmstat_show(struct seq_file
*m
, void *arg
)
2287 unsigned long *l
= arg
;
2288 unsigned long off
= l
- (unsigned long *)m
->private;
2290 seq_printf(m
, "%s %lu\n", vmstat_text
[off
], *l
);
2294 static void vmstat_stop(struct seq_file
*m
, void *arg
)
2300 struct seq_operations vmstat_op
= {
2301 .start
= vmstat_start
,
2302 .next
= vmstat_next
,
2303 .stop
= vmstat_stop
,
2304 .show
= vmstat_show
,
2307 #endif /* CONFIG_PROC_FS */
2309 #ifdef CONFIG_HOTPLUG_CPU
2310 static int page_alloc_cpu_notify(struct notifier_block
*self
,
2311 unsigned long action
, void *hcpu
)
2313 int cpu
= (unsigned long)hcpu
;
2315 unsigned long *src
, *dest
;
2317 if (action
== CPU_DEAD
) {
2320 /* Drain local pagecache count. */
2321 count
= &per_cpu(nr_pagecache_local
, cpu
);
2322 atomic_add(*count
, &nr_pagecache
);
2324 local_irq_disable();
2327 /* Add dead cpu's page_states to our own. */
2328 dest
= (unsigned long *)&__get_cpu_var(page_states
);
2329 src
= (unsigned long *)&per_cpu(page_states
, cpu
);
2331 for (i
= 0; i
< sizeof(struct page_state
)/sizeof(unsigned long);
2341 #endif /* CONFIG_HOTPLUG_CPU */
2343 void __init
page_alloc_init(void)
2345 hotcpu_notifier(page_alloc_cpu_notify
, 0);
2349 * setup_per_zone_lowmem_reserve - called whenever
2350 * sysctl_lower_zone_reserve_ratio changes. Ensures that each zone
2351 * has a correct pages reserved value, so an adequate number of
2352 * pages are left in the zone after a successful __alloc_pages().
2354 static void setup_per_zone_lowmem_reserve(void)
2356 struct pglist_data
*pgdat
;
2359 for_each_pgdat(pgdat
) {
2360 for (j
= 0; j
< MAX_NR_ZONES
; j
++) {
2361 struct zone
*zone
= pgdat
->node_zones
+ j
;
2362 unsigned long present_pages
= zone
->present_pages
;
2364 zone
->lowmem_reserve
[j
] = 0;
2366 for (idx
= j
-1; idx
>= 0; idx
--) {
2367 struct zone
*lower_zone
;
2369 if (sysctl_lowmem_reserve_ratio
[idx
] < 1)
2370 sysctl_lowmem_reserve_ratio
[idx
] = 1;
2372 lower_zone
= pgdat
->node_zones
+ idx
;
2373 lower_zone
->lowmem_reserve
[j
] = present_pages
/
2374 sysctl_lowmem_reserve_ratio
[idx
];
2375 present_pages
+= lower_zone
->present_pages
;
2382 * setup_per_zone_pages_min - called when min_free_kbytes changes. Ensures
2383 * that the pages_{min,low,high} values for each zone are set correctly
2384 * with respect to min_free_kbytes.
2386 void setup_per_zone_pages_min(void)
2388 unsigned long pages_min
= min_free_kbytes
>> (PAGE_SHIFT
- 10);
2389 unsigned long lowmem_pages
= 0;
2391 unsigned long flags
;
2393 /* Calculate total number of !ZONE_HIGHMEM pages */
2394 for_each_zone(zone
) {
2395 if (!is_highmem(zone
))
2396 lowmem_pages
+= zone
->present_pages
;
2399 for_each_zone(zone
) {
2401 spin_lock_irqsave(&zone
->lru_lock
, flags
);
2402 tmp
= (pages_min
* zone
->present_pages
) / lowmem_pages
;
2403 if (is_highmem(zone
)) {
2405 * __GFP_HIGH and PF_MEMALLOC allocations usually don't
2406 * need highmem pages, so cap pages_min to a small
2409 * The (pages_high-pages_low) and (pages_low-pages_min)
2410 * deltas controls asynch page reclaim, and so should
2411 * not be capped for highmem.
2415 min_pages
= zone
->present_pages
/ 1024;
2416 if (min_pages
< SWAP_CLUSTER_MAX
)
2417 min_pages
= SWAP_CLUSTER_MAX
;
2418 if (min_pages
> 128)
2420 zone
->pages_min
= min_pages
;
2423 * If it's a lowmem zone, reserve a number of pages
2424 * proportionate to the zone's size.
2426 zone
->pages_min
= tmp
;
2429 zone
->pages_low
= zone
->pages_min
+ tmp
/ 4;
2430 zone
->pages_high
= zone
->pages_min
+ tmp
/ 2;
2431 spin_unlock_irqrestore(&zone
->lru_lock
, flags
);
2436 * Initialise min_free_kbytes.
2438 * For small machines we want it small (128k min). For large machines
2439 * we want it large (64MB max). But it is not linear, because network
2440 * bandwidth does not increase linearly with machine size. We use
2442 * min_free_kbytes = 4 * sqrt(lowmem_kbytes), for better accuracy:
2443 * min_free_kbytes = sqrt(lowmem_kbytes * 16)
2459 static int __init
init_per_zone_pages_min(void)
2461 unsigned long lowmem_kbytes
;
2463 lowmem_kbytes
= nr_free_buffer_pages() * (PAGE_SIZE
>> 10);
2465 min_free_kbytes
= int_sqrt(lowmem_kbytes
* 16);
2466 if (min_free_kbytes
< 128)
2467 min_free_kbytes
= 128;
2468 if (min_free_kbytes
> 65536)
2469 min_free_kbytes
= 65536;
2470 setup_per_zone_pages_min();
2471 setup_per_zone_lowmem_reserve();
2474 module_init(init_per_zone_pages_min
)
2477 * min_free_kbytes_sysctl_handler - just a wrapper around proc_dointvec() so
2478 * that we can call two helper functions whenever min_free_kbytes
2481 int min_free_kbytes_sysctl_handler(ctl_table
*table
, int write
,
2482 struct file
*file
, void __user
*buffer
, size_t *length
, loff_t
*ppos
)
2484 proc_dointvec(table
, write
, file
, buffer
, length
, ppos
);
2485 setup_per_zone_pages_min();
2490 * lowmem_reserve_ratio_sysctl_handler - just a wrapper around
2491 * proc_dointvec() so that we can call setup_per_zone_lowmem_reserve()
2492 * whenever sysctl_lowmem_reserve_ratio changes.
2494 * The reserve ratio obviously has absolutely no relation with the
2495 * pages_min watermarks. The lowmem reserve ratio can only make sense
2496 * if in function of the boot time zone sizes.
2498 int lowmem_reserve_ratio_sysctl_handler(ctl_table
*table
, int write
,
2499 struct file
*file
, void __user
*buffer
, size_t *length
, loff_t
*ppos
)
2501 proc_dointvec_minmax(table
, write
, file
, buffer
, length
, ppos
);
2502 setup_per_zone_lowmem_reserve();
2506 __initdata
int hashdist
= HASHDIST_DEFAULT
;
2509 static int __init
set_hashdist(char *str
)
2513 hashdist
= simple_strtoul(str
, &str
, 0);
2516 __setup("hashdist=", set_hashdist
);
2520 * allocate a large system hash table from bootmem
2521 * - it is assumed that the hash table must contain an exact power-of-2
2522 * quantity of entries
2523 * - limit is the number of hash buckets, not the total allocation size
2525 void *__init
alloc_large_system_hash(const char *tablename
,
2526 unsigned long bucketsize
,
2527 unsigned long numentries
,
2530 unsigned int *_hash_shift
,
2531 unsigned int *_hash_mask
,
2532 unsigned long limit
)
2534 unsigned long long max
= limit
;
2535 unsigned long log2qty
, size
;
2538 /* allow the kernel cmdline to have a say */
2540 /* round applicable memory size up to nearest megabyte */
2541 numentries
= (flags
& HASH_HIGHMEM
) ? nr_all_pages
: nr_kernel_pages
;
2542 numentries
+= (1UL << (20 - PAGE_SHIFT
)) - 1;
2543 numentries
>>= 20 - PAGE_SHIFT
;
2544 numentries
<<= 20 - PAGE_SHIFT
;
2546 /* limit to 1 bucket per 2^scale bytes of low memory */
2547 if (scale
> PAGE_SHIFT
)
2548 numentries
>>= (scale
- PAGE_SHIFT
);
2550 numentries
<<= (PAGE_SHIFT
- scale
);
2552 /* rounded up to nearest power of 2 in size */
2553 numentries
= 1UL << (long_log2(numentries
) + 1);
2555 /* limit allocation size to 1/16 total memory by default */
2557 max
= ((unsigned long long)nr_all_pages
<< PAGE_SHIFT
) >> 4;
2558 do_div(max
, bucketsize
);
2561 if (numentries
> max
)
2564 log2qty
= long_log2(numentries
);
2567 size
= bucketsize
<< log2qty
;
2568 if (flags
& HASH_EARLY
)
2569 table
= alloc_bootmem(size
);
2571 table
= __vmalloc(size
, GFP_ATOMIC
, PAGE_KERNEL
);
2573 unsigned long order
;
2574 for (order
= 0; ((1UL << order
) << PAGE_SHIFT
) < size
; order
++)
2576 table
= (void*) __get_free_pages(GFP_ATOMIC
, order
);
2578 } while (!table
&& size
> PAGE_SIZE
&& --log2qty
);
2581 panic("Failed to allocate %s hash table\n", tablename
);
2583 printk("%s hash table entries: %d (order: %d, %lu bytes)\n",
2586 long_log2(size
) - PAGE_SHIFT
,
2590 *_hash_shift
= log2qty
;
2592 *_hash_mask
= (1 << log2qty
) - 1;