blob: 1d6ba6a4b594e7db82617c67449831482f52412d [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/mm/page_alloc.c
3 *
4 * Manages the free list, the system allocates free pages here.
5 * Note that kmalloc() lives in slab.c
6 *
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)
15 */
16
17#include <linux/config.h>
18#include <linux/stddef.h>
19#include <linux/mm.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/module.h>
26#include <linux/suspend.h>
27#include <linux/pagevec.h>
28#include <linux/blkdev.h>
29#include <linux/slab.h>
30#include <linux/notifier.h>
31#include <linux/topology.h>
32#include <linux/sysctl.h>
33#include <linux/cpu.h>
34#include <linux/cpuset.h>
35#include <linux/nodemask.h>
36#include <linux/vmalloc.h>
37
38#include <asm/tlbflush.h>
39#include "internal.h"
40
41/*
42 * MCD - HACK: Find somewhere to initialize this EARLY, or make this
43 * initializer cleaner
44 */
45nodemask_t node_online_map = { { [0] = 1UL } };
Dean Nelson7223a932005-03-23 19:00:00 -070046EXPORT_SYMBOL(node_online_map);
Linus Torvalds1da177e2005-04-16 15:20:36 -070047nodemask_t node_possible_map = NODE_MASK_ALL;
Dean Nelson7223a932005-03-23 19:00:00 -070048EXPORT_SYMBOL(node_possible_map);
Linus Torvalds1da177e2005-04-16 15:20:36 -070049struct pglist_data *pgdat_list;
50unsigned long totalram_pages;
51unsigned long totalhigh_pages;
52long nr_swap_pages;
53
54/*
55 * results with 256, 32 in the lowmem_reserve sysctl:
56 * 1G machine -> (16M dma, 800M-16M normal, 1G-800M high)
57 * 1G machine -> (16M dma, 784M normal, 224M high)
58 * NORMAL allocation will leave 784M/256 of ram reserved in the ZONE_DMA
59 * HIGHMEM allocation will leave 224M/32 of ram reserved in ZONE_NORMAL
60 * HIGHMEM allocation will (224M+784M)/256 of ram reserved in ZONE_DMA
61 */
62int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES-1] = { 256, 32 };
63
64EXPORT_SYMBOL(totalram_pages);
65EXPORT_SYMBOL(nr_swap_pages);
66
67/*
68 * Used by page_zone() to look up the address of the struct zone whose
69 * id is encoded in the upper bits of page->flags
70 */
Andy Whitcroftd41dee32005-06-23 00:07:54 -070071struct zone *zone_table[1 << ZONETABLE_SHIFT];
Linus Torvalds1da177e2005-04-16 15:20:36 -070072EXPORT_SYMBOL(zone_table);
73
74static char *zone_names[MAX_NR_ZONES] = { "DMA", "Normal", "HighMem" };
75int min_free_kbytes = 1024;
76
77unsigned long __initdata nr_kernel_pages;
78unsigned long __initdata nr_all_pages;
79
80/*
81 * Temporary debugging check for pages not lying within a given zone.
82 */
83static int bad_range(struct zone *zone, struct page *page)
84{
85 if (page_to_pfn(page) >= zone->zone_start_pfn + zone->spanned_pages)
86 return 1;
87 if (page_to_pfn(page) < zone->zone_start_pfn)
88 return 1;
89#ifdef CONFIG_HOLES_IN_ZONE
90 if (!pfn_valid(page_to_pfn(page)))
91 return 1;
92#endif
93 if (zone != page_zone(page))
94 return 1;
95 return 0;
96}
97
98static void bad_page(const char *function, struct page *page)
99{
100 printk(KERN_EMERG "Bad page state at %s (in process '%s', page %p)\n",
101 function, current->comm, page);
102 printk(KERN_EMERG "flags:0x%0*lx mapping:%p mapcount:%d count:%d\n",
103 (int)(2*sizeof(page_flags_t)), (unsigned long)page->flags,
104 page->mapping, page_mapcount(page), page_count(page));
105 printk(KERN_EMERG "Backtrace:\n");
106 dump_stack();
107 printk(KERN_EMERG "Trying to fix it up, but a reboot is needed\n");
Hugh Dickins334795e2005-06-21 17:15:08 -0700108 page->flags &= ~(1 << PG_lru |
109 1 << PG_private |
Linus Torvalds1da177e2005-04-16 15:20:36 -0700110 1 << PG_locked |
Linus Torvalds1da177e2005-04-16 15:20:36 -0700111 1 << PG_active |
112 1 << PG_dirty |
Hugh Dickins334795e2005-06-21 17:15:08 -0700113 1 << PG_reclaim |
114 1 << PG_slab |
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115 1 << PG_swapcache |
116 1 << PG_writeback);
117 set_page_count(page, 0);
118 reset_page_mapcount(page);
119 page->mapping = NULL;
120 tainted |= TAINT_BAD_PAGE;
121}
122
123#ifndef CONFIG_HUGETLB_PAGE
124#define prep_compound_page(page, order) do { } while (0)
125#define destroy_compound_page(page, order) do { } while (0)
126#else
127/*
128 * Higher-order pages are called "compound pages". They are structured thusly:
129 *
130 * The first PAGE_SIZE page is called the "head page".
131 *
132 * The remaining PAGE_SIZE pages are called "tail pages".
133 *
134 * All pages have PG_compound set. All pages have their ->private pointing at
135 * the head page (even the head page has this).
136 *
137 * The first tail page's ->mapping, if non-zero, holds the address of the
138 * compound page's put_page() function.
139 *
140 * The order of the allocation is stored in the first tail page's ->index
141 * This is only for debug at present. This usage means that zero-order pages
142 * may not be compound.
143 */
144static void prep_compound_page(struct page *page, unsigned long order)
145{
146 int i;
147 int nr_pages = 1 << order;
148
149 page[1].mapping = NULL;
150 page[1].index = order;
151 for (i = 0; i < nr_pages; i++) {
152 struct page *p = page + i;
153
154 SetPageCompound(p);
155 p->private = (unsigned long)page;
156 }
157}
158
159static void destroy_compound_page(struct page *page, unsigned long order)
160{
161 int i;
162 int nr_pages = 1 << order;
163
164 if (!PageCompound(page))
165 return;
166
167 if (page[1].index != order)
168 bad_page(__FUNCTION__, page);
169
170 for (i = 0; i < nr_pages; i++) {
171 struct page *p = page + i;
172
173 if (!PageCompound(p))
174 bad_page(__FUNCTION__, page);
175 if (p->private != (unsigned long)page)
176 bad_page(__FUNCTION__, page);
177 ClearPageCompound(p);
178 }
179}
180#endif /* CONFIG_HUGETLB_PAGE */
181
182/*
183 * function for dealing with page's order in buddy system.
184 * zone->lock is already acquired when we use these.
185 * So, we don't need atomic page->flags operations here.
186 */
187static inline unsigned long page_order(struct page *page) {
188 return page->private;
189}
190
191static inline void set_page_order(struct page *page, int order) {
192 page->private = order;
193 __SetPagePrivate(page);
194}
195
196static inline void rmv_page_order(struct page *page)
197{
198 __ClearPagePrivate(page);
199 page->private = 0;
200}
201
202/*
203 * Locate the struct page for both the matching buddy in our
204 * pair (buddy1) and the combined O(n+1) page they form (page).
205 *
206 * 1) Any buddy B1 will have an order O twin B2 which satisfies
207 * the following equation:
208 * B2 = B1 ^ (1 << O)
209 * For example, if the starting buddy (buddy2) is #8 its order
210 * 1 buddy is #10:
211 * B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10
212 *
213 * 2) Any buddy B will have an order O+1 parent P which
214 * satisfies the following equation:
215 * P = B & ~(1 << O)
216 *
217 * Assumption: *_mem_map is contigious at least up to MAX_ORDER
218 */
219static inline struct page *
220__page_find_buddy(struct page *page, unsigned long page_idx, unsigned int order)
221{
222 unsigned long buddy_idx = page_idx ^ (1 << order);
223
224 return page + (buddy_idx - page_idx);
225}
226
227static inline unsigned long
228__find_combined_index(unsigned long page_idx, unsigned int order)
229{
230 return (page_idx & ~(1 << order));
231}
232
233/*
234 * This function checks whether a page is free && is the buddy
235 * we can do coalesce a page and its buddy if
236 * (a) the buddy is free &&
237 * (b) the buddy is on the buddy system &&
238 * (c) a page and its buddy have the same order.
239 * for recording page's order, we use page->private and PG_private.
240 *
241 */
242static inline int page_is_buddy(struct page *page, int order)
243{
244 if (PagePrivate(page) &&
245 (page_order(page) == order) &&
246 !PageReserved(page) &&
247 page_count(page) == 0)
248 return 1;
249 return 0;
250}
251
252/*
253 * Freeing function for a buddy system allocator.
254 *
255 * The concept of a buddy system is to maintain direct-mapped table
256 * (containing bit values) for memory blocks of various "orders".
257 * The bottom level table contains the map for the smallest allocatable
258 * units of memory (here, pages), and each level above it describes
259 * pairs of units from the levels below, hence, "buddies".
260 * At a high level, all that happens here is marking the table entry
261 * at the bottom level available, and propagating the changes upward
262 * as necessary, plus some accounting needed to play nicely with other
263 * parts of the VM system.
264 * At each level, we keep a list of pages, which are heads of continuous
265 * free pages of length of (1 << order) and marked with PG_Private.Page's
266 * order is recorded in page->private field.
267 * So when we are allocating or freeing one, we can derive the state of the
268 * other. That is, if we allocate a small block, and both were
269 * free, the remainder of the region must be split into blocks.
270 * If a block is freed, and its buddy is also free, then this
271 * triggers coalescing into a block of larger size.
272 *
273 * -- wli
274 */
275
276static inline void __free_pages_bulk (struct page *page,
277 struct zone *zone, unsigned int order)
278{
279 unsigned long page_idx;
280 int order_size = 1 << order;
281
282 if (unlikely(order))
283 destroy_compound_page(page, order);
284
285 page_idx = page_to_pfn(page) & ((1 << MAX_ORDER) - 1);
286
287 BUG_ON(page_idx & (order_size - 1));
288 BUG_ON(bad_range(zone, page));
289
290 zone->free_pages += order_size;
291 while (order < MAX_ORDER-1) {
292 unsigned long combined_idx;
293 struct free_area *area;
294 struct page *buddy;
295
296 combined_idx = __find_combined_index(page_idx, order);
297 buddy = __page_find_buddy(page, page_idx, order);
298
299 if (bad_range(zone, buddy))
300 break;
301 if (!page_is_buddy(buddy, order))
302 break; /* Move the buddy up one level. */
303 list_del(&buddy->lru);
304 area = zone->free_area + order;
305 area->nr_free--;
306 rmv_page_order(buddy);
307 page = page + (combined_idx - page_idx);
308 page_idx = combined_idx;
309 order++;
310 }
311 set_page_order(page, order);
312 list_add(&page->lru, &zone->free_area[order].free_list);
313 zone->free_area[order].nr_free++;
314}
315
316static inline void free_pages_check(const char *function, struct page *page)
317{
318 if ( page_mapcount(page) ||
319 page->mapping != NULL ||
320 page_count(page) != 0 ||
321 (page->flags & (
322 1 << PG_lru |
323 1 << PG_private |
324 1 << PG_locked |
325 1 << PG_active |
326 1 << PG_reclaim |
327 1 << PG_slab |
328 1 << PG_swapcache |
329 1 << PG_writeback )))
330 bad_page(function, page);
331 if (PageDirty(page))
332 ClearPageDirty(page);
333}
334
335/*
336 * Frees a list of pages.
337 * Assumes all pages on list are in same zone, and of same order.
338 * count is the number of pages to free, or 0 for all on the list.
339 *
340 * If the zone was previously in an "all pages pinned" state then look to
341 * see if this freeing clears that state.
342 *
343 * And clear the zone's pages_scanned counter, to hold off the "all pages are
344 * pinned" detection logic.
345 */
346static int
347free_pages_bulk(struct zone *zone, int count,
348 struct list_head *list, unsigned int order)
349{
350 unsigned long flags;
351 struct page *page = NULL;
352 int ret = 0;
353
354 spin_lock_irqsave(&zone->lock, flags);
355 zone->all_unreclaimable = 0;
356 zone->pages_scanned = 0;
357 while (!list_empty(list) && count--) {
358 page = list_entry(list->prev, struct page, lru);
359 /* have to delete it as __free_pages_bulk list manipulates */
360 list_del(&page->lru);
361 __free_pages_bulk(page, zone, order);
362 ret++;
363 }
364 spin_unlock_irqrestore(&zone->lock, flags);
365 return ret;
366}
367
368void __free_pages_ok(struct page *page, unsigned int order)
369{
370 LIST_HEAD(list);
371 int i;
372
373 arch_free_page(page, order);
374
375 mod_page_state(pgfree, 1 << order);
376
377#ifndef CONFIG_MMU
378 if (order > 0)
379 for (i = 1 ; i < (1 << order) ; ++i)
380 __put_page(page + i);
381#endif
382
383 for (i = 0 ; i < (1 << order) ; ++i)
384 free_pages_check(__FUNCTION__, page + i);
385 list_add(&page->lru, &list);
386 kernel_map_pages(page, 1<<order, 0);
387 free_pages_bulk(page_zone(page), 1, &list, order);
388}
389
390
391/*
392 * The order of subdivision here is critical for the IO subsystem.
393 * Please do not alter this order without good reasons and regression
394 * testing. Specifically, as large blocks of memory are subdivided,
395 * the order in which smaller blocks are delivered depends on the order
396 * they're subdivided in this function. This is the primary factor
397 * influencing the order in which pages are delivered to the IO
398 * subsystem according to empirical testing, and this is also justified
399 * by considering the behavior of a buddy system containing a single
400 * large block of memory acted on by a series of small allocations.
401 * This behavior is a critical factor in sglist merging's success.
402 *
403 * -- wli
404 */
405static inline struct page *
406expand(struct zone *zone, struct page *page,
407 int low, int high, struct free_area *area)
408{
409 unsigned long size = 1 << high;
410
411 while (high > low) {
412 area--;
413 high--;
414 size >>= 1;
415 BUG_ON(bad_range(zone, &page[size]));
416 list_add(&page[size].lru, &area->free_list);
417 area->nr_free++;
418 set_page_order(&page[size], high);
419 }
420 return page;
421}
422
423void set_page_refs(struct page *page, int order)
424{
425#ifdef CONFIG_MMU
426 set_page_count(page, 1);
427#else
428 int i;
429
430 /*
431 * We need to reference all the pages for this order, otherwise if
432 * anyone accesses one of the pages with (get/put) it will be freed.
433 * - eg: access_process_vm()
434 */
435 for (i = 0; i < (1 << order); i++)
436 set_page_count(page + i, 1);
437#endif /* CONFIG_MMU */
438}
439
440/*
441 * This page is about to be returned from the page allocator
442 */
443static void prep_new_page(struct page *page, int order)
444{
Hugh Dickins334795e2005-06-21 17:15:08 -0700445 if ( page_mapcount(page) ||
446 page->mapping != NULL ||
447 page_count(page) != 0 ||
448 (page->flags & (
449 1 << PG_lru |
Linus Torvalds1da177e2005-04-16 15:20:36 -0700450 1 << PG_private |
451 1 << PG_locked |
Linus Torvalds1da177e2005-04-16 15:20:36 -0700452 1 << PG_active |
453 1 << PG_dirty |
454 1 << PG_reclaim |
Hugh Dickins334795e2005-06-21 17:15:08 -0700455 1 << PG_slab |
Linus Torvalds1da177e2005-04-16 15:20:36 -0700456 1 << PG_swapcache |
457 1 << PG_writeback )))
458 bad_page(__FUNCTION__, page);
459
460 page->flags &= ~(1 << PG_uptodate | 1 << PG_error |
461 1 << PG_referenced | 1 << PG_arch_1 |
462 1 << PG_checked | 1 << PG_mappedtodisk);
463 page->private = 0;
464 set_page_refs(page, order);
465 kernel_map_pages(page, 1 << order, 1);
466}
467
468/*
469 * Do the hard work of removing an element from the buddy allocator.
470 * Call me with the zone->lock already held.
471 */
472static struct page *__rmqueue(struct zone *zone, unsigned int order)
473{
474 struct free_area * area;
475 unsigned int current_order;
476 struct page *page;
477
478 for (current_order = order; current_order < MAX_ORDER; ++current_order) {
479 area = zone->free_area + current_order;
480 if (list_empty(&area->free_list))
481 continue;
482
483 page = list_entry(area->free_list.next, struct page, lru);
484 list_del(&page->lru);
485 rmv_page_order(page);
486 area->nr_free--;
487 zone->free_pages -= 1UL << order;
488 return expand(zone, page, order, current_order, area);
489 }
490
491 return NULL;
492}
493
494/*
495 * Obtain a specified number of elements from the buddy allocator, all under
496 * a single hold of the lock, for efficiency. Add them to the supplied list.
497 * Returns the number of new pages which were placed at *list.
498 */
499static int rmqueue_bulk(struct zone *zone, unsigned int order,
500 unsigned long count, struct list_head *list)
501{
502 unsigned long flags;
503 int i;
504 int allocated = 0;
505 struct page *page;
506
507 spin_lock_irqsave(&zone->lock, flags);
508 for (i = 0; i < count; ++i) {
509 page = __rmqueue(zone, order);
510 if (page == NULL)
511 break;
512 allocated++;
513 list_add_tail(&page->lru, list);
514 }
515 spin_unlock_irqrestore(&zone->lock, flags);
516 return allocated;
517}
518
Christoph Lameter4ae7c032005-06-21 17:14:57 -0700519#ifdef CONFIG_NUMA
520/* Called from the slab reaper to drain remote pagesets */
521void drain_remote_pages(void)
522{
523 struct zone *zone;
524 int i;
525 unsigned long flags;
526
527 local_irq_save(flags);
528 for_each_zone(zone) {
529 struct per_cpu_pageset *pset;
530
531 /* Do not drain local pagesets */
532 if (zone->zone_pgdat->node_id == numa_node_id())
533 continue;
534
535 pset = zone->pageset[smp_processor_id()];
536 for (i = 0; i < ARRAY_SIZE(pset->pcp); i++) {
537 struct per_cpu_pages *pcp;
538
539 pcp = &pset->pcp[i];
540 if (pcp->count)
541 pcp->count -= free_pages_bulk(zone, pcp->count,
542 &pcp->list, 0);
543 }
544 }
545 local_irq_restore(flags);
546}
547#endif
548
Linus Torvalds1da177e2005-04-16 15:20:36 -0700549#if defined(CONFIG_PM) || defined(CONFIG_HOTPLUG_CPU)
550static void __drain_pages(unsigned int cpu)
551{
552 struct zone *zone;
553 int i;
554
555 for_each_zone(zone) {
556 struct per_cpu_pageset *pset;
557
Christoph Lametere7c8d5c2005-06-21 17:14:47 -0700558 pset = zone_pcp(zone, cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700559 for (i = 0; i < ARRAY_SIZE(pset->pcp); i++) {
560 struct per_cpu_pages *pcp;
561
562 pcp = &pset->pcp[i];
563 pcp->count -= free_pages_bulk(zone, pcp->count,
564 &pcp->list, 0);
565 }
566 }
567}
568#endif /* CONFIG_PM || CONFIG_HOTPLUG_CPU */
569
570#ifdef CONFIG_PM
571
572void mark_free_pages(struct zone *zone)
573{
574 unsigned long zone_pfn, flags;
575 int order;
576 struct list_head *curr;
577
578 if (!zone->spanned_pages)
579 return;
580
581 spin_lock_irqsave(&zone->lock, flags);
582 for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn)
583 ClearPageNosaveFree(pfn_to_page(zone_pfn + zone->zone_start_pfn));
584
585 for (order = MAX_ORDER - 1; order >= 0; --order)
586 list_for_each(curr, &zone->free_area[order].free_list) {
587 unsigned long start_pfn, i;
588
589 start_pfn = page_to_pfn(list_entry(curr, struct page, lru));
590
591 for (i=0; i < (1<<order); i++)
592 SetPageNosaveFree(pfn_to_page(start_pfn+i));
593 }
594 spin_unlock_irqrestore(&zone->lock, flags);
595}
596
597/*
598 * Spill all of this CPU's per-cpu pages back into the buddy allocator.
599 */
600void drain_local_pages(void)
601{
602 unsigned long flags;
603
604 local_irq_save(flags);
605 __drain_pages(smp_processor_id());
606 local_irq_restore(flags);
607}
608#endif /* CONFIG_PM */
609
610static void zone_statistics(struct zonelist *zonelist, struct zone *z)
611{
612#ifdef CONFIG_NUMA
613 unsigned long flags;
614 int cpu;
615 pg_data_t *pg = z->zone_pgdat;
616 pg_data_t *orig = zonelist->zones[0]->zone_pgdat;
617 struct per_cpu_pageset *p;
618
619 local_irq_save(flags);
620 cpu = smp_processor_id();
Christoph Lametere7c8d5c2005-06-21 17:14:47 -0700621 p = zone_pcp(z,cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700622 if (pg == orig) {
Christoph Lametere7c8d5c2005-06-21 17:14:47 -0700623 p->numa_hit++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700624 } else {
625 p->numa_miss++;
Christoph Lametere7c8d5c2005-06-21 17:14:47 -0700626 zone_pcp(zonelist->zones[0], cpu)->numa_foreign++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700627 }
628 if (pg == NODE_DATA(numa_node_id()))
629 p->local_node++;
630 else
631 p->other_node++;
632 local_irq_restore(flags);
633#endif
634}
635
636/*
637 * Free a 0-order page
638 */
639static void FASTCALL(free_hot_cold_page(struct page *page, int cold));
640static void fastcall free_hot_cold_page(struct page *page, int cold)
641{
642 struct zone *zone = page_zone(page);
643 struct per_cpu_pages *pcp;
644 unsigned long flags;
645
646 arch_free_page(page, 0);
647
648 kernel_map_pages(page, 1, 0);
649 inc_page_state(pgfree);
650 if (PageAnon(page))
651 page->mapping = NULL;
652 free_pages_check(__FUNCTION__, page);
Christoph Lametere7c8d5c2005-06-21 17:14:47 -0700653 pcp = &zone_pcp(zone, get_cpu())->pcp[cold];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700654 local_irq_save(flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700655 list_add(&page->lru, &pcp->list);
656 pcp->count++;
Christoph Lameter2caaad42005-06-21 17:15:00 -0700657 if (pcp->count >= pcp->high)
658 pcp->count -= free_pages_bulk(zone, pcp->batch, &pcp->list, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700659 local_irq_restore(flags);
660 put_cpu();
661}
662
663void fastcall free_hot_page(struct page *page)
664{
665 free_hot_cold_page(page, 0);
666}
667
668void fastcall free_cold_page(struct page *page)
669{
670 free_hot_cold_page(page, 1);
671}
672
673static inline void prep_zero_page(struct page *page, int order, unsigned int __nocast gfp_flags)
674{
675 int i;
676
677 BUG_ON((gfp_flags & (__GFP_WAIT | __GFP_HIGHMEM)) == __GFP_HIGHMEM);
678 for(i = 0; i < (1 << order); i++)
679 clear_highpage(page + i);
680}
681
682/*
683 * Really, prep_compound_page() should be called from __rmqueue_bulk(). But
684 * we cheat by calling it from here, in the order > 0 path. Saves a branch
685 * or two.
686 */
687static struct page *
688buffered_rmqueue(struct zone *zone, int order, unsigned int __nocast gfp_flags)
689{
690 unsigned long flags;
691 struct page *page = NULL;
692 int cold = !!(gfp_flags & __GFP_COLD);
693
694 if (order == 0) {
695 struct per_cpu_pages *pcp;
696
Christoph Lametere7c8d5c2005-06-21 17:14:47 -0700697 pcp = &zone_pcp(zone, get_cpu())->pcp[cold];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700698 local_irq_save(flags);
699 if (pcp->count <= pcp->low)
700 pcp->count += rmqueue_bulk(zone, 0,
701 pcp->batch, &pcp->list);
702 if (pcp->count) {
703 page = list_entry(pcp->list.next, struct page, lru);
704 list_del(&page->lru);
705 pcp->count--;
706 }
707 local_irq_restore(flags);
708 put_cpu();
709 }
710
711 if (page == NULL) {
712 spin_lock_irqsave(&zone->lock, flags);
713 page = __rmqueue(zone, order);
714 spin_unlock_irqrestore(&zone->lock, flags);
715 }
716
717 if (page != NULL) {
718 BUG_ON(bad_range(zone, page));
719 mod_page_state_zone(zone, pgalloc, 1 << order);
720 prep_new_page(page, order);
721
722 if (gfp_flags & __GFP_ZERO)
723 prep_zero_page(page, order, gfp_flags);
724
725 if (order && (gfp_flags & __GFP_COMP))
726 prep_compound_page(page, order);
727 }
728 return page;
729}
730
731/*
732 * Return 1 if free pages are above 'mark'. This takes into account the order
733 * of the allocation.
734 */
735int zone_watermark_ok(struct zone *z, int order, unsigned long mark,
736 int classzone_idx, int can_try_harder, int gfp_high)
737{
738 /* free_pages my go negative - that's OK */
739 long min = mark, free_pages = z->free_pages - (1 << order) + 1;
740 int o;
741
742 if (gfp_high)
743 min -= min / 2;
744 if (can_try_harder)
745 min -= min / 4;
746
747 if (free_pages <= min + z->lowmem_reserve[classzone_idx])
748 return 0;
749 for (o = 0; o < order; o++) {
750 /* At the next order, this order's pages become unavailable */
751 free_pages -= z->free_area[o].nr_free << o;
752
753 /* Require fewer higher order pages to be free */
754 min >>= 1;
755
756 if (free_pages <= min)
757 return 0;
758 }
759 return 1;
760}
761
Martin Hicks753ee722005-06-21 17:14:41 -0700762static inline int
763should_reclaim_zone(struct zone *z, unsigned int gfp_mask)
764{
765 if (!z->reclaim_pages)
766 return 0;
Martin Hicks0c35bba2005-06-21 17:14:42 -0700767 if (gfp_mask & __GFP_NORECLAIM)
768 return 0;
Martin Hicks753ee722005-06-21 17:14:41 -0700769 return 1;
770}
771
Linus Torvalds1da177e2005-04-16 15:20:36 -0700772/*
773 * This is the 'heart' of the zoned buddy allocator.
774 */
775struct page * fastcall
776__alloc_pages(unsigned int __nocast gfp_mask, unsigned int order,
777 struct zonelist *zonelist)
778{
779 const int wait = gfp_mask & __GFP_WAIT;
780 struct zone **zones, *z;
781 struct page *page;
782 struct reclaim_state reclaim_state;
783 struct task_struct *p = current;
784 int i;
785 int classzone_idx;
786 int do_retry;
787 int can_try_harder;
788 int did_some_progress;
789
790 might_sleep_if(wait);
791
792 /*
793 * The caller may dip into page reserves a bit more if the caller
794 * cannot run direct reclaim, or is the caller has realtime scheduling
795 * policy
796 */
797 can_try_harder = (unlikely(rt_task(p)) && !in_interrupt()) || !wait;
798
799 zones = zonelist->zones; /* the list of zones suitable for gfp_mask */
800
801 if (unlikely(zones[0] == NULL)) {
802 /* Should this ever happen?? */
803 return NULL;
804 }
805
806 classzone_idx = zone_idx(zones[0]);
807
Martin Hicks753ee722005-06-21 17:14:41 -0700808restart:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700809 /* Go through the zonelist once, looking for a zone with enough free */
810 for (i = 0; (z = zones[i]) != NULL; i++) {
Martin Hicks753ee722005-06-21 17:14:41 -0700811 int do_reclaim = should_reclaim_zone(z, gfp_mask);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700812
813 if (!cpuset_zone_allowed(z))
814 continue;
815
Martin Hicks753ee722005-06-21 17:14:41 -0700816 /*
817 * If the zone is to attempt early page reclaim then this loop
818 * will try to reclaim pages and check the watermark a second
819 * time before giving up and falling back to the next zone.
820 */
821zone_reclaim_retry:
822 if (!zone_watermark_ok(z, order, z->pages_low,
823 classzone_idx, 0, 0)) {
824 if (!do_reclaim)
825 continue;
826 else {
827 zone_reclaim(z, gfp_mask, order);
828 /* Only try reclaim once */
829 do_reclaim = 0;
830 goto zone_reclaim_retry;
831 }
832 }
833
Linus Torvalds1da177e2005-04-16 15:20:36 -0700834 page = buffered_rmqueue(z, order, gfp_mask);
835 if (page)
836 goto got_pg;
837 }
838
839 for (i = 0; (z = zones[i]) != NULL; i++)
840 wakeup_kswapd(z, order);
841
842 /*
843 * Go through the zonelist again. Let __GFP_HIGH and allocations
844 * coming from realtime tasks to go deeper into reserves
845 *
846 * This is the last chance, in general, before the goto nopage.
847 * Ignore cpuset if GFP_ATOMIC (!wait) rather than fail alloc.
848 */
849 for (i = 0; (z = zones[i]) != NULL; i++) {
850 if (!zone_watermark_ok(z, order, z->pages_min,
851 classzone_idx, can_try_harder,
852 gfp_mask & __GFP_HIGH))
853 continue;
854
855 if (wait && !cpuset_zone_allowed(z))
856 continue;
857
858 page = buffered_rmqueue(z, order, gfp_mask);
859 if (page)
860 goto got_pg;
861 }
862
863 /* This allocation should allow future memory freeing. */
Nick Pigginb84a35b2005-05-01 08:58:36 -0700864
865 if (((p->flags & PF_MEMALLOC) || unlikely(test_thread_flag(TIF_MEMDIE)))
866 && !in_interrupt()) {
867 if (!(gfp_mask & __GFP_NOMEMALLOC)) {
868 /* go through the zonelist yet again, ignoring mins */
869 for (i = 0; (z = zones[i]) != NULL; i++) {
870 if (!cpuset_zone_allowed(z))
871 continue;
872 page = buffered_rmqueue(z, order, gfp_mask);
873 if (page)
874 goto got_pg;
875 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700876 }
877 goto nopage;
878 }
879
880 /* Atomic allocations - we can't balance anything */
881 if (!wait)
882 goto nopage;
883
884rebalance:
885 cond_resched();
886
887 /* We now go into synchronous reclaim */
888 p->flags |= PF_MEMALLOC;
889 reclaim_state.reclaimed_slab = 0;
890 p->reclaim_state = &reclaim_state;
891
Darren Hart1ad539b2005-06-21 17:14:53 -0700892 did_some_progress = try_to_free_pages(zones, gfp_mask);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700893
894 p->reclaim_state = NULL;
895 p->flags &= ~PF_MEMALLOC;
896
897 cond_resched();
898
899 if (likely(did_some_progress)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700900 for (i = 0; (z = zones[i]) != NULL; i++) {
901 if (!zone_watermark_ok(z, order, z->pages_min,
902 classzone_idx, can_try_harder,
903 gfp_mask & __GFP_HIGH))
904 continue;
905
906 if (!cpuset_zone_allowed(z))
907 continue;
908
909 page = buffered_rmqueue(z, order, gfp_mask);
910 if (page)
911 goto got_pg;
912 }
913 } else if ((gfp_mask & __GFP_FS) && !(gfp_mask & __GFP_NORETRY)) {
914 /*
915 * Go through the zonelist yet one more time, keep
916 * very high watermark here, this is only to catch
917 * a parallel oom killing, we must fail if we're still
918 * under heavy pressure.
919 */
920 for (i = 0; (z = zones[i]) != NULL; i++) {
921 if (!zone_watermark_ok(z, order, z->pages_high,
922 classzone_idx, 0, 0))
923 continue;
924
925 if (!cpuset_zone_allowed(z))
926 continue;
927
928 page = buffered_rmqueue(z, order, gfp_mask);
929 if (page)
930 goto got_pg;
931 }
932
Marcelo Tosatti79b9ce32005-07-07 17:56:04 -0700933 out_of_memory(gfp_mask, order);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700934 goto restart;
935 }
936
937 /*
938 * Don't let big-order allocations loop unless the caller explicitly
939 * requests that. Wait for some write requests to complete then retry.
940 *
941 * In this implementation, __GFP_REPEAT means __GFP_NOFAIL for order
942 * <= 3, but that may not be true in other implementations.
943 */
944 do_retry = 0;
945 if (!(gfp_mask & __GFP_NORETRY)) {
946 if ((order <= 3) || (gfp_mask & __GFP_REPEAT))
947 do_retry = 1;
948 if (gfp_mask & __GFP_NOFAIL)
949 do_retry = 1;
950 }
951 if (do_retry) {
952 blk_congestion_wait(WRITE, HZ/50);
953 goto rebalance;
954 }
955
956nopage:
957 if (!(gfp_mask & __GFP_NOWARN) && printk_ratelimit()) {
958 printk(KERN_WARNING "%s: page allocation failure."
959 " order:%d, mode:0x%x\n",
960 p->comm, order, gfp_mask);
961 dump_stack();
Janet Morgan578c2fd2005-06-21 17:14:56 -0700962 show_mem();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700963 }
964 return NULL;
965got_pg:
966 zone_statistics(zonelist, z);
967 return page;
968}
969
970EXPORT_SYMBOL(__alloc_pages);
971
972/*
973 * Common helper functions.
974 */
975fastcall unsigned long __get_free_pages(unsigned int __nocast gfp_mask, unsigned int order)
976{
977 struct page * page;
978 page = alloc_pages(gfp_mask, order);
979 if (!page)
980 return 0;
981 return (unsigned long) page_address(page);
982}
983
984EXPORT_SYMBOL(__get_free_pages);
985
986fastcall unsigned long get_zeroed_page(unsigned int __nocast gfp_mask)
987{
988 struct page * page;
989
990 /*
991 * get_zeroed_page() returns a 32-bit address, which cannot represent
992 * a highmem page
993 */
994 BUG_ON(gfp_mask & __GFP_HIGHMEM);
995
996 page = alloc_pages(gfp_mask | __GFP_ZERO, 0);
997 if (page)
998 return (unsigned long) page_address(page);
999 return 0;
1000}
1001
1002EXPORT_SYMBOL(get_zeroed_page);
1003
1004void __pagevec_free(struct pagevec *pvec)
1005{
1006 int i = pagevec_count(pvec);
1007
1008 while (--i >= 0)
1009 free_hot_cold_page(pvec->pages[i], pvec->cold);
1010}
1011
1012fastcall void __free_pages(struct page *page, unsigned int order)
1013{
1014 if (!PageReserved(page) && put_page_testzero(page)) {
1015 if (order == 0)
1016 free_hot_page(page);
1017 else
1018 __free_pages_ok(page, order);
1019 }
1020}
1021
1022EXPORT_SYMBOL(__free_pages);
1023
1024fastcall void free_pages(unsigned long addr, unsigned int order)
1025{
1026 if (addr != 0) {
1027 BUG_ON(!virt_addr_valid((void *)addr));
1028 __free_pages(virt_to_page((void *)addr), order);
1029 }
1030}
1031
1032EXPORT_SYMBOL(free_pages);
1033
1034/*
1035 * Total amount of free (allocatable) RAM:
1036 */
1037unsigned int nr_free_pages(void)
1038{
1039 unsigned int sum = 0;
1040 struct zone *zone;
1041
1042 for_each_zone(zone)
1043 sum += zone->free_pages;
1044
1045 return sum;
1046}
1047
1048EXPORT_SYMBOL(nr_free_pages);
1049
1050#ifdef CONFIG_NUMA
1051unsigned int nr_free_pages_pgdat(pg_data_t *pgdat)
1052{
1053 unsigned int i, sum = 0;
1054
1055 for (i = 0; i < MAX_NR_ZONES; i++)
1056 sum += pgdat->node_zones[i].free_pages;
1057
1058 return sum;
1059}
1060#endif
1061
1062static unsigned int nr_free_zone_pages(int offset)
1063{
1064 pg_data_t *pgdat;
1065 unsigned int sum = 0;
1066
1067 for_each_pgdat(pgdat) {
1068 struct zonelist *zonelist = pgdat->node_zonelists + offset;
1069 struct zone **zonep = zonelist->zones;
1070 struct zone *zone;
1071
1072 for (zone = *zonep++; zone; zone = *zonep++) {
1073 unsigned long size = zone->present_pages;
1074 unsigned long high = zone->pages_high;
1075 if (size > high)
1076 sum += size - high;
1077 }
1078 }
1079
1080 return sum;
1081}
1082
1083/*
1084 * Amount of free RAM allocatable within ZONE_DMA and ZONE_NORMAL
1085 */
1086unsigned int nr_free_buffer_pages(void)
1087{
1088 return nr_free_zone_pages(GFP_USER & GFP_ZONEMASK);
1089}
1090
1091/*
1092 * Amount of free RAM allocatable within all zones
1093 */
1094unsigned int nr_free_pagecache_pages(void)
1095{
1096 return nr_free_zone_pages(GFP_HIGHUSER & GFP_ZONEMASK);
1097}
1098
1099#ifdef CONFIG_HIGHMEM
1100unsigned int nr_free_highpages (void)
1101{
1102 pg_data_t *pgdat;
1103 unsigned int pages = 0;
1104
1105 for_each_pgdat(pgdat)
1106 pages += pgdat->node_zones[ZONE_HIGHMEM].free_pages;
1107
1108 return pages;
1109}
1110#endif
1111
1112#ifdef CONFIG_NUMA
1113static void show_node(struct zone *zone)
1114{
1115 printk("Node %d ", zone->zone_pgdat->node_id);
1116}
1117#else
1118#define show_node(zone) do { } while (0)
1119#endif
1120
1121/*
1122 * Accumulate the page_state information across all CPUs.
1123 * The result is unavoidably approximate - it can change
1124 * during and after execution of this function.
1125 */
1126static DEFINE_PER_CPU(struct page_state, page_states) = {0};
1127
1128atomic_t nr_pagecache = ATOMIC_INIT(0);
1129EXPORT_SYMBOL(nr_pagecache);
1130#ifdef CONFIG_SMP
1131DEFINE_PER_CPU(long, nr_pagecache_local) = 0;
1132#endif
1133
1134void __get_page_state(struct page_state *ret, int nr)
1135{
1136 int cpu = 0;
1137
1138 memset(ret, 0, sizeof(*ret));
1139
1140 cpu = first_cpu(cpu_online_map);
1141 while (cpu < NR_CPUS) {
1142 unsigned long *in, *out, off;
1143
1144 in = (unsigned long *)&per_cpu(page_states, cpu);
1145
1146 cpu = next_cpu(cpu, cpu_online_map);
1147
1148 if (cpu < NR_CPUS)
1149 prefetch(&per_cpu(page_states, cpu));
1150
1151 out = (unsigned long *)ret;
1152 for (off = 0; off < nr; off++)
1153 *out++ += *in++;
1154 }
1155}
1156
1157void get_page_state(struct page_state *ret)
1158{
1159 int nr;
1160
1161 nr = offsetof(struct page_state, GET_PAGE_STATE_LAST);
1162 nr /= sizeof(unsigned long);
1163
1164 __get_page_state(ret, nr + 1);
1165}
1166
1167void get_full_page_state(struct page_state *ret)
1168{
1169 __get_page_state(ret, sizeof(*ret) / sizeof(unsigned long));
1170}
1171
Benjamin LaHaisec2f29ea2005-06-21 17:14:55 -07001172unsigned long __read_page_state(unsigned long offset)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001173{
1174 unsigned long ret = 0;
1175 int cpu;
1176
1177 for_each_online_cpu(cpu) {
1178 unsigned long in;
1179
1180 in = (unsigned long)&per_cpu(page_states, cpu) + offset;
1181 ret += *((unsigned long *)in);
1182 }
1183 return ret;
1184}
1185
Benjamin LaHaise83e5d8f2005-06-21 17:14:54 -07001186void __mod_page_state(unsigned long offset, unsigned long delta)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001187{
1188 unsigned long flags;
1189 void* ptr;
1190
1191 local_irq_save(flags);
1192 ptr = &__get_cpu_var(page_states);
1193 *(unsigned long*)(ptr + offset) += delta;
1194 local_irq_restore(flags);
1195}
1196
1197EXPORT_SYMBOL(__mod_page_state);
1198
1199void __get_zone_counts(unsigned long *active, unsigned long *inactive,
1200 unsigned long *free, struct pglist_data *pgdat)
1201{
1202 struct zone *zones = pgdat->node_zones;
1203 int i;
1204
1205 *active = 0;
1206 *inactive = 0;
1207 *free = 0;
1208 for (i = 0; i < MAX_NR_ZONES; i++) {
1209 *active += zones[i].nr_active;
1210 *inactive += zones[i].nr_inactive;
1211 *free += zones[i].free_pages;
1212 }
1213}
1214
1215void get_zone_counts(unsigned long *active,
1216 unsigned long *inactive, unsigned long *free)
1217{
1218 struct pglist_data *pgdat;
1219
1220 *active = 0;
1221 *inactive = 0;
1222 *free = 0;
1223 for_each_pgdat(pgdat) {
1224 unsigned long l, m, n;
1225 __get_zone_counts(&l, &m, &n, pgdat);
1226 *active += l;
1227 *inactive += m;
1228 *free += n;
1229 }
1230}
1231
1232void si_meminfo(struct sysinfo *val)
1233{
1234 val->totalram = totalram_pages;
1235 val->sharedram = 0;
1236 val->freeram = nr_free_pages();
1237 val->bufferram = nr_blockdev_pages();
1238#ifdef CONFIG_HIGHMEM
1239 val->totalhigh = totalhigh_pages;
1240 val->freehigh = nr_free_highpages();
1241#else
1242 val->totalhigh = 0;
1243 val->freehigh = 0;
1244#endif
1245 val->mem_unit = PAGE_SIZE;
1246}
1247
1248EXPORT_SYMBOL(si_meminfo);
1249
1250#ifdef CONFIG_NUMA
1251void si_meminfo_node(struct sysinfo *val, int nid)
1252{
1253 pg_data_t *pgdat = NODE_DATA(nid);
1254
1255 val->totalram = pgdat->node_present_pages;
1256 val->freeram = nr_free_pages_pgdat(pgdat);
1257 val->totalhigh = pgdat->node_zones[ZONE_HIGHMEM].present_pages;
1258 val->freehigh = pgdat->node_zones[ZONE_HIGHMEM].free_pages;
1259 val->mem_unit = PAGE_SIZE;
1260}
1261#endif
1262
1263#define K(x) ((x) << (PAGE_SHIFT-10))
1264
1265/*
1266 * Show free area list (used inside shift_scroll-lock stuff)
1267 * We also calculate the percentage fragmentation. We do this by counting the
1268 * memory on each free list with the exception of the first item on the list.
1269 */
1270void show_free_areas(void)
1271{
1272 struct page_state ps;
1273 int cpu, temperature;
1274 unsigned long active;
1275 unsigned long inactive;
1276 unsigned long free;
1277 struct zone *zone;
1278
1279 for_each_zone(zone) {
1280 show_node(zone);
1281 printk("%s per-cpu:", zone->name);
1282
1283 if (!zone->present_pages) {
1284 printk(" empty\n");
1285 continue;
1286 } else
1287 printk("\n");
1288
1289 for (cpu = 0; cpu < NR_CPUS; ++cpu) {
1290 struct per_cpu_pageset *pageset;
1291
1292 if (!cpu_possible(cpu))
1293 continue;
1294
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07001295 pageset = zone_pcp(zone, cpu);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001296
1297 for (temperature = 0; temperature < 2; temperature++)
Christoph Lameter4ae7c032005-06-21 17:14:57 -07001298 printk("cpu %d %s: low %d, high %d, batch %d used:%d\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -07001299 cpu,
1300 temperature ? "cold" : "hot",
1301 pageset->pcp[temperature].low,
1302 pageset->pcp[temperature].high,
Christoph Lameter4ae7c032005-06-21 17:14:57 -07001303 pageset->pcp[temperature].batch,
1304 pageset->pcp[temperature].count);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001305 }
1306 }
1307
1308 get_page_state(&ps);
1309 get_zone_counts(&active, &inactive, &free);
1310
Denis Vlasenkoc0d62212005-06-21 17:15:14 -07001311 printk("Free pages: %11ukB (%ukB HighMem)\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -07001312 K(nr_free_pages()),
1313 K(nr_free_highpages()));
1314
1315 printk("Active:%lu inactive:%lu dirty:%lu writeback:%lu "
1316 "unstable:%lu free:%u slab:%lu mapped:%lu pagetables:%lu\n",
1317 active,
1318 inactive,
1319 ps.nr_dirty,
1320 ps.nr_writeback,
1321 ps.nr_unstable,
1322 nr_free_pages(),
1323 ps.nr_slab,
1324 ps.nr_mapped,
1325 ps.nr_page_table_pages);
1326
1327 for_each_zone(zone) {
1328 int i;
1329
1330 show_node(zone);
1331 printk("%s"
1332 " free:%lukB"
1333 " min:%lukB"
1334 " low:%lukB"
1335 " high:%lukB"
1336 " active:%lukB"
1337 " inactive:%lukB"
1338 " present:%lukB"
1339 " pages_scanned:%lu"
1340 " all_unreclaimable? %s"
1341 "\n",
1342 zone->name,
1343 K(zone->free_pages),
1344 K(zone->pages_min),
1345 K(zone->pages_low),
1346 K(zone->pages_high),
1347 K(zone->nr_active),
1348 K(zone->nr_inactive),
1349 K(zone->present_pages),
1350 zone->pages_scanned,
1351 (zone->all_unreclaimable ? "yes" : "no")
1352 );
1353 printk("lowmem_reserve[]:");
1354 for (i = 0; i < MAX_NR_ZONES; i++)
1355 printk(" %lu", zone->lowmem_reserve[i]);
1356 printk("\n");
1357 }
1358
1359 for_each_zone(zone) {
1360 unsigned long nr, flags, order, total = 0;
1361
1362 show_node(zone);
1363 printk("%s: ", zone->name);
1364 if (!zone->present_pages) {
1365 printk("empty\n");
1366 continue;
1367 }
1368
1369 spin_lock_irqsave(&zone->lock, flags);
1370 for (order = 0; order < MAX_ORDER; order++) {
1371 nr = zone->free_area[order].nr_free;
1372 total += nr << order;
1373 printk("%lu*%lukB ", nr, K(1UL) << order);
1374 }
1375 spin_unlock_irqrestore(&zone->lock, flags);
1376 printk("= %lukB\n", K(total));
1377 }
1378
1379 show_swap_cache_info();
1380}
1381
1382/*
1383 * Builds allocation fallback zone lists.
1384 */
1385static int __init build_zonelists_node(pg_data_t *pgdat, struct zonelist *zonelist, int j, int k)
1386{
1387 switch (k) {
1388 struct zone *zone;
1389 default:
1390 BUG();
1391 case ZONE_HIGHMEM:
1392 zone = pgdat->node_zones + ZONE_HIGHMEM;
1393 if (zone->present_pages) {
1394#ifndef CONFIG_HIGHMEM
1395 BUG();
1396#endif
1397 zonelist->zones[j++] = zone;
1398 }
1399 case ZONE_NORMAL:
1400 zone = pgdat->node_zones + ZONE_NORMAL;
1401 if (zone->present_pages)
1402 zonelist->zones[j++] = zone;
1403 case ZONE_DMA:
1404 zone = pgdat->node_zones + ZONE_DMA;
1405 if (zone->present_pages)
1406 zonelist->zones[j++] = zone;
1407 }
1408
1409 return j;
1410}
1411
1412#ifdef CONFIG_NUMA
1413#define MAX_NODE_LOAD (num_online_nodes())
1414static int __initdata node_load[MAX_NUMNODES];
1415/**
Pavel Pisa4dc3b162005-05-01 08:59:25 -07001416 * find_next_best_node - find the next node that should appear in a given node's fallback list
Linus Torvalds1da177e2005-04-16 15:20:36 -07001417 * @node: node whose fallback list we're appending
1418 * @used_node_mask: nodemask_t of already used nodes
1419 *
1420 * We use a number of factors to determine which is the next node that should
1421 * appear on a given node's fallback list. The node should not have appeared
1422 * already in @node's fallback list, and it should be the next closest node
1423 * according to the distance array (which contains arbitrary distance values
1424 * from each node to each node in the system), and should also prefer nodes
1425 * with no CPUs, since presumably they'll have very little allocation pressure
1426 * on them otherwise.
1427 * It returns -1 if no node is found.
1428 */
1429static int __init find_next_best_node(int node, nodemask_t *used_node_mask)
1430{
1431 int i, n, val;
1432 int min_val = INT_MAX;
1433 int best_node = -1;
1434
1435 for_each_online_node(i) {
1436 cpumask_t tmp;
1437
1438 /* Start from local node */
1439 n = (node+i) % num_online_nodes();
1440
1441 /* Don't want a node to appear more than once */
1442 if (node_isset(n, *used_node_mask))
1443 continue;
1444
1445 /* Use the local node if we haven't already */
1446 if (!node_isset(node, *used_node_mask)) {
1447 best_node = node;
1448 break;
1449 }
1450
1451 /* Use the distance array to find the distance */
1452 val = node_distance(node, n);
1453
1454 /* Give preference to headless and unused nodes */
1455 tmp = node_to_cpumask(n);
1456 if (!cpus_empty(tmp))
1457 val += PENALTY_FOR_NODE_WITH_CPUS;
1458
1459 /* Slight preference for less loaded node */
1460 val *= (MAX_NODE_LOAD*MAX_NUMNODES);
1461 val += node_load[n];
1462
1463 if (val < min_val) {
1464 min_val = val;
1465 best_node = n;
1466 }
1467 }
1468
1469 if (best_node >= 0)
1470 node_set(best_node, *used_node_mask);
1471
1472 return best_node;
1473}
1474
1475static void __init build_zonelists(pg_data_t *pgdat)
1476{
1477 int i, j, k, node, local_node;
1478 int prev_node, load;
1479 struct zonelist *zonelist;
1480 nodemask_t used_mask;
1481
1482 /* initialize zonelists */
1483 for (i = 0; i < GFP_ZONETYPES; i++) {
1484 zonelist = pgdat->node_zonelists + i;
1485 zonelist->zones[0] = NULL;
1486 }
1487
1488 /* NUMA-aware ordering of nodes */
1489 local_node = pgdat->node_id;
1490 load = num_online_nodes();
1491 prev_node = local_node;
1492 nodes_clear(used_mask);
1493 while ((node = find_next_best_node(local_node, &used_mask)) >= 0) {
1494 /*
1495 * We don't want to pressure a particular node.
1496 * So adding penalty to the first node in same
1497 * distance group to make it round-robin.
1498 */
1499 if (node_distance(local_node, node) !=
1500 node_distance(local_node, prev_node))
1501 node_load[node] += load;
1502 prev_node = node;
1503 load--;
1504 for (i = 0; i < GFP_ZONETYPES; i++) {
1505 zonelist = pgdat->node_zonelists + i;
1506 for (j = 0; zonelist->zones[j] != NULL; j++);
1507
1508 k = ZONE_NORMAL;
1509 if (i & __GFP_HIGHMEM)
1510 k = ZONE_HIGHMEM;
1511 if (i & __GFP_DMA)
1512 k = ZONE_DMA;
1513
1514 j = build_zonelists_node(NODE_DATA(node), zonelist, j, k);
1515 zonelist->zones[j] = NULL;
1516 }
1517 }
1518}
1519
1520#else /* CONFIG_NUMA */
1521
1522static void __init build_zonelists(pg_data_t *pgdat)
1523{
1524 int i, j, k, node, local_node;
1525
1526 local_node = pgdat->node_id;
1527 for (i = 0; i < GFP_ZONETYPES; i++) {
1528 struct zonelist *zonelist;
1529
1530 zonelist = pgdat->node_zonelists + i;
1531
1532 j = 0;
1533 k = ZONE_NORMAL;
1534 if (i & __GFP_HIGHMEM)
1535 k = ZONE_HIGHMEM;
1536 if (i & __GFP_DMA)
1537 k = ZONE_DMA;
1538
1539 j = build_zonelists_node(pgdat, zonelist, j, k);
1540 /*
1541 * Now we build the zonelist so that it contains the zones
1542 * of all the other nodes.
1543 * We don't want to pressure a particular node, so when
1544 * building the zones for node N, we make sure that the
1545 * zones coming right after the local ones are those from
1546 * node N+1 (modulo N)
1547 */
1548 for (node = local_node + 1; node < MAX_NUMNODES; node++) {
1549 if (!node_online(node))
1550 continue;
1551 j = build_zonelists_node(NODE_DATA(node), zonelist, j, k);
1552 }
1553 for (node = 0; node < local_node; node++) {
1554 if (!node_online(node))
1555 continue;
1556 j = build_zonelists_node(NODE_DATA(node), zonelist, j, k);
1557 }
1558
1559 zonelist->zones[j] = NULL;
1560 }
1561}
1562
1563#endif /* CONFIG_NUMA */
1564
1565void __init build_all_zonelists(void)
1566{
1567 int i;
1568
1569 for_each_online_node(i)
1570 build_zonelists(NODE_DATA(i));
1571 printk("Built %i zonelists\n", num_online_nodes());
1572 cpuset_init_current_mems_allowed();
1573}
1574
1575/*
1576 * Helper functions to size the waitqueue hash table.
1577 * Essentially these want to choose hash table sizes sufficiently
1578 * large so that collisions trying to wait on pages are rare.
1579 * But in fact, the number of active page waitqueues on typical
1580 * systems is ridiculously low, less than 200. So this is even
1581 * conservative, even though it seems large.
1582 *
1583 * The constant PAGES_PER_WAITQUEUE specifies the ratio of pages to
1584 * waitqueues, i.e. the size of the waitq table given the number of pages.
1585 */
1586#define PAGES_PER_WAITQUEUE 256
1587
1588static inline unsigned long wait_table_size(unsigned long pages)
1589{
1590 unsigned long size = 1;
1591
1592 pages /= PAGES_PER_WAITQUEUE;
1593
1594 while (size < pages)
1595 size <<= 1;
1596
1597 /*
1598 * Once we have dozens or even hundreds of threads sleeping
1599 * on IO we've got bigger problems than wait queue collision.
1600 * Limit the size of the wait table to a reasonable size.
1601 */
1602 size = min(size, 4096UL);
1603
1604 return max(size, 4UL);
1605}
1606
1607/*
1608 * This is an integer logarithm so that shifts can be used later
1609 * to extract the more random high bits from the multiplicative
1610 * hash function before the remainder is taken.
1611 */
1612static inline unsigned long wait_table_bits(unsigned long size)
1613{
1614 return ffz(~size);
1615}
1616
1617#define LONG_ALIGN(x) (((x)+(sizeof(long))-1)&~((sizeof(long))-1))
1618
1619static void __init calculate_zone_totalpages(struct pglist_data *pgdat,
1620 unsigned long *zones_size, unsigned long *zholes_size)
1621{
1622 unsigned long realtotalpages, totalpages = 0;
1623 int i;
1624
1625 for (i = 0; i < MAX_NR_ZONES; i++)
1626 totalpages += zones_size[i];
1627 pgdat->node_spanned_pages = totalpages;
1628
1629 realtotalpages = totalpages;
1630 if (zholes_size)
1631 for (i = 0; i < MAX_NR_ZONES; i++)
1632 realtotalpages -= zholes_size[i];
1633 pgdat->node_present_pages = realtotalpages;
1634 printk(KERN_DEBUG "On node %d totalpages: %lu\n", pgdat->node_id, realtotalpages);
1635}
1636
1637
1638/*
1639 * Initially all pages are reserved - free ones are freed
1640 * up by free_all_bootmem() once the early boot process is
1641 * done. Non-atomic initialization, single-pass.
1642 */
1643void __init memmap_init_zone(unsigned long size, int nid, unsigned long zone,
1644 unsigned long start_pfn)
1645{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001646 struct page *page;
Andy Whitcroft29751f62005-06-23 00:08:00 -07001647 unsigned long end_pfn = start_pfn + size;
1648 unsigned long pfn;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001649
Andy Whitcroftd41dee32005-06-23 00:07:54 -07001650 for (pfn = start_pfn; pfn < end_pfn; pfn++, page++) {
1651 if (!early_pfn_valid(pfn))
1652 continue;
Andy Whitcroft641c7672005-06-23 00:07:59 -07001653 if (!early_pfn_in_nid(pfn, nid))
1654 continue;
Andy Whitcroftd41dee32005-06-23 00:07:54 -07001655 page = pfn_to_page(pfn);
1656 set_page_links(page, zone, nid, pfn);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001657 set_page_count(page, 0);
1658 reset_page_mapcount(page);
1659 SetPageReserved(page);
1660 INIT_LIST_HEAD(&page->lru);
1661#ifdef WANT_PAGE_VIRTUAL
1662 /* The shift won't overflow because ZONE_NORMAL is below 4G. */
1663 if (!is_highmem_idx(zone))
Bob Picco3212c6b2005-06-27 14:36:28 -07001664 set_page_address(page, __va(pfn << PAGE_SHIFT));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001665#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001666 }
1667}
1668
1669void zone_init_free_lists(struct pglist_data *pgdat, struct zone *zone,
1670 unsigned long size)
1671{
1672 int order;
1673 for (order = 0; order < MAX_ORDER ; order++) {
1674 INIT_LIST_HEAD(&zone->free_area[order].free_list);
1675 zone->free_area[order].nr_free = 0;
1676 }
1677}
1678
Andy Whitcroftd41dee32005-06-23 00:07:54 -07001679#define ZONETABLE_INDEX(x, zone_nr) ((x << ZONES_SHIFT) | zone_nr)
1680void zonetable_add(struct zone *zone, int nid, int zid, unsigned long pfn,
1681 unsigned long size)
1682{
1683 unsigned long snum = pfn_to_section_nr(pfn);
1684 unsigned long end = pfn_to_section_nr(pfn + size);
1685
1686 if (FLAGS_HAS_NODE)
1687 zone_table[ZONETABLE_INDEX(nid, zid)] = zone;
1688 else
1689 for (; snum <= end; snum++)
1690 zone_table[ZONETABLE_INDEX(snum, zid)] = zone;
1691}
1692
Linus Torvalds1da177e2005-04-16 15:20:36 -07001693#ifndef __HAVE_ARCH_MEMMAP_INIT
1694#define memmap_init(size, nid, zone, start_pfn) \
1695 memmap_init_zone((size), (nid), (zone), (start_pfn))
1696#endif
1697
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07001698static int __devinit zone_batchsize(struct zone *zone)
1699{
1700 int batch;
1701
1702 /*
1703 * The per-cpu-pages pools are set to around 1000th of the
1704 * size of the zone. But no more than 1/4 of a meg - there's
1705 * no point in going beyond the size of L2 cache.
1706 *
1707 * OK, so we don't know how big the cache is. So guess.
1708 */
1709 batch = zone->present_pages / 1024;
1710 if (batch * PAGE_SIZE > 256 * 1024)
1711 batch = (256 * 1024) / PAGE_SIZE;
1712 batch /= 4; /* We effectively *= 4 below */
1713 if (batch < 1)
1714 batch = 1;
1715
1716 /*
1717 * Clamp the batch to a 2^n - 1 value. Having a power
1718 * of 2 value was found to be more likely to have
1719 * suboptimal cache aliasing properties in some cases.
1720 *
1721 * For example if 2 tasks are alternately allocating
1722 * batches of pages, one task can end up with a lot
1723 * of pages of one half of the possible page colors
1724 * and the other with pages of the other colors.
1725 */
1726 batch = (1 << fls(batch + batch/2)) - 1;
1727 return batch;
1728}
1729
Christoph Lameter2caaad42005-06-21 17:15:00 -07001730inline void setup_pageset(struct per_cpu_pageset *p, unsigned long batch)
1731{
1732 struct per_cpu_pages *pcp;
1733
1734 pcp = &p->pcp[0]; /* hot */
1735 pcp->count = 0;
1736 pcp->low = 2 * batch;
1737 pcp->high = 6 * batch;
1738 pcp->batch = max(1UL, 1 * batch);
1739 INIT_LIST_HEAD(&pcp->list);
1740
1741 pcp = &p->pcp[1]; /* cold*/
1742 pcp->count = 0;
1743 pcp->low = 0;
1744 pcp->high = 2 * batch;
1745 pcp->batch = max(1UL, 1 * batch);
1746 INIT_LIST_HEAD(&pcp->list);
1747}
1748
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07001749#ifdef CONFIG_NUMA
1750/*
Christoph Lameter2caaad42005-06-21 17:15:00 -07001751 * Boot pageset table. One per cpu which is going to be used for all
1752 * zones and all nodes. The parameters will be set in such a way
1753 * that an item put on a list will immediately be handed over to
1754 * the buddy list. This is safe since pageset manipulation is done
1755 * with interrupts disabled.
1756 *
1757 * Some NUMA counter updates may also be caught by the boot pagesets.
Christoph Lameterb7c84c62005-06-22 20:26:07 -07001758 *
1759 * The boot_pagesets must be kept even after bootup is complete for
1760 * unused processors and/or zones. They do play a role for bootstrapping
1761 * hotplugged processors.
1762 *
1763 * zoneinfo_show() and maybe other functions do
1764 * not check if the processor is online before following the pageset pointer.
1765 * Other parts of the kernel may not check if the zone is available.
Christoph Lameter2caaad42005-06-21 17:15:00 -07001766 */
1767static struct per_cpu_pageset
Christoph Lameterb7c84c62005-06-22 20:26:07 -07001768 boot_pageset[NR_CPUS];
Christoph Lameter2caaad42005-06-21 17:15:00 -07001769
1770/*
1771 * Dynamically allocate memory for the
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07001772 * per cpu pageset array in struct zone.
1773 */
1774static int __devinit process_zones(int cpu)
1775{
1776 struct zone *zone, *dzone;
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07001777
1778 for_each_zone(zone) {
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07001779
Christoph Lameter2caaad42005-06-21 17:15:00 -07001780 zone->pageset[cpu] = kmalloc_node(sizeof(struct per_cpu_pageset),
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07001781 GFP_KERNEL, cpu_to_node(cpu));
Christoph Lameter2caaad42005-06-21 17:15:00 -07001782 if (!zone->pageset[cpu])
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07001783 goto bad;
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07001784
Christoph Lameter2caaad42005-06-21 17:15:00 -07001785 setup_pageset(zone->pageset[cpu], zone_batchsize(zone));
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07001786 }
1787
1788 return 0;
1789bad:
1790 for_each_zone(dzone) {
1791 if (dzone == zone)
1792 break;
1793 kfree(dzone->pageset[cpu]);
1794 dzone->pageset[cpu] = NULL;
1795 }
1796 return -ENOMEM;
1797}
1798
1799static inline void free_zone_pagesets(int cpu)
1800{
1801#ifdef CONFIG_NUMA
1802 struct zone *zone;
1803
1804 for_each_zone(zone) {
1805 struct per_cpu_pageset *pset = zone_pcp(zone, cpu);
1806
1807 zone_pcp(zone, cpu) = NULL;
1808 kfree(pset);
1809 }
1810#endif
1811}
1812
1813static int __devinit pageset_cpuup_callback(struct notifier_block *nfb,
1814 unsigned long action,
1815 void *hcpu)
1816{
1817 int cpu = (long)hcpu;
1818 int ret = NOTIFY_OK;
1819
1820 switch (action) {
1821 case CPU_UP_PREPARE:
1822 if (process_zones(cpu))
1823 ret = NOTIFY_BAD;
1824 break;
1825#ifdef CONFIG_HOTPLUG_CPU
1826 case CPU_DEAD:
1827 free_zone_pagesets(cpu);
1828 break;
1829#endif
1830 default:
1831 break;
1832 }
1833 return ret;
1834}
1835
1836static struct notifier_block pageset_notifier =
1837 { &pageset_cpuup_callback, NULL, 0 };
1838
1839void __init setup_per_cpu_pageset()
1840{
1841 int err;
1842
1843 /* Initialize per_cpu_pageset for cpu 0.
1844 * A cpuup callback will do this for every cpu
1845 * as it comes online
1846 */
1847 err = process_zones(smp_processor_id());
1848 BUG_ON(err);
1849 register_cpu_notifier(&pageset_notifier);
1850}
1851
1852#endif
1853
Linus Torvalds1da177e2005-04-16 15:20:36 -07001854/*
1855 * Set up the zone data structures:
1856 * - mark all pages reserved
1857 * - mark all memory queues empty
1858 * - clear the memory bitmaps
1859 */
1860static void __init free_area_init_core(struct pglist_data *pgdat,
1861 unsigned long *zones_size, unsigned long *zholes_size)
1862{
1863 unsigned long i, j;
1864 const unsigned long zone_required_alignment = 1UL << (MAX_ORDER-1);
1865 int cpu, nid = pgdat->node_id;
1866 unsigned long zone_start_pfn = pgdat->node_start_pfn;
1867
1868 pgdat->nr_zones = 0;
1869 init_waitqueue_head(&pgdat->kswapd_wait);
1870 pgdat->kswapd_max_order = 0;
1871
1872 for (j = 0; j < MAX_NR_ZONES; j++) {
1873 struct zone *zone = pgdat->node_zones + j;
1874 unsigned long size, realsize;
1875 unsigned long batch;
1876
Linus Torvalds1da177e2005-04-16 15:20:36 -07001877 realsize = size = zones_size[j];
1878 if (zholes_size)
1879 realsize -= zholes_size[j];
1880
1881 if (j == ZONE_DMA || j == ZONE_NORMAL)
1882 nr_kernel_pages += realsize;
1883 nr_all_pages += realsize;
1884
1885 zone->spanned_pages = size;
1886 zone->present_pages = realsize;
1887 zone->name = zone_names[j];
1888 spin_lock_init(&zone->lock);
1889 spin_lock_init(&zone->lru_lock);
1890 zone->zone_pgdat = pgdat;
1891 zone->free_pages = 0;
1892
1893 zone->temp_priority = zone->prev_priority = DEF_PRIORITY;
1894
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07001895 batch = zone_batchsize(zone);
Nick Piggin8e30f272005-05-01 08:58:36 -07001896
Linus Torvalds1da177e2005-04-16 15:20:36 -07001897 for (cpu = 0; cpu < NR_CPUS; cpu++) {
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07001898#ifdef CONFIG_NUMA
Christoph Lameter2caaad42005-06-21 17:15:00 -07001899 /* Early boot. Slab allocator not functional yet */
1900 zone->pageset[cpu] = &boot_pageset[cpu];
1901 setup_pageset(&boot_pageset[cpu],0);
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07001902#else
Christoph Lameter2caaad42005-06-21 17:15:00 -07001903 setup_pageset(zone_pcp(zone,cpu), batch);
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07001904#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001905 }
1906 printk(KERN_DEBUG " %s zone: %lu pages, LIFO batch:%lu\n",
1907 zone_names[j], realsize, batch);
1908 INIT_LIST_HEAD(&zone->active_list);
1909 INIT_LIST_HEAD(&zone->inactive_list);
1910 zone->nr_scan_active = 0;
1911 zone->nr_scan_inactive = 0;
1912 zone->nr_active = 0;
1913 zone->nr_inactive = 0;
Martin Hicks1e7e5a92005-06-21 17:14:43 -07001914 atomic_set(&zone->reclaim_in_progress, -1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001915 if (!size)
1916 continue;
1917
1918 /*
1919 * The per-page waitqueue mechanism uses hashed waitqueues
1920 * per zone.
1921 */
1922 zone->wait_table_size = wait_table_size(size);
1923 zone->wait_table_bits =
1924 wait_table_bits(zone->wait_table_size);
1925 zone->wait_table = (wait_queue_head_t *)
1926 alloc_bootmem_node(pgdat, zone->wait_table_size
1927 * sizeof(wait_queue_head_t));
1928
1929 for(i = 0; i < zone->wait_table_size; ++i)
1930 init_waitqueue_head(zone->wait_table + i);
1931
1932 pgdat->nr_zones = j+1;
1933
1934 zone->zone_mem_map = pfn_to_page(zone_start_pfn);
1935 zone->zone_start_pfn = zone_start_pfn;
1936
1937 if ((zone_start_pfn) & (zone_required_alignment-1))
1938 printk(KERN_CRIT "BUG: wrong zone alignment, it will crash\n");
1939
1940 memmap_init(size, nid, j, zone_start_pfn);
1941
Andy Whitcroftd41dee32005-06-23 00:07:54 -07001942 zonetable_add(zone, nid, j, zone_start_pfn, size);
1943
Linus Torvalds1da177e2005-04-16 15:20:36 -07001944 zone_start_pfn += size;
1945
1946 zone_init_free_lists(pgdat, zone, zone->spanned_pages);
1947 }
1948}
1949
1950static void __init alloc_node_mem_map(struct pglist_data *pgdat)
1951{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001952 /* Skip empty nodes */
1953 if (!pgdat->node_spanned_pages)
1954 return;
1955
Andy Whitcroftd41dee32005-06-23 00:07:54 -07001956#ifdef CONFIG_FLAT_NODE_MEM_MAP
Linus Torvalds1da177e2005-04-16 15:20:36 -07001957 /* ia64 gets its own node_mem_map, before this, without bootmem */
1958 if (!pgdat->node_mem_map) {
Andy Whitcroftd41dee32005-06-23 00:07:54 -07001959 unsigned long size;
1960 struct page *map;
1961
Linus Torvalds1da177e2005-04-16 15:20:36 -07001962 size = (pgdat->node_spanned_pages + 1) * sizeof(struct page);
Dave Hansen6f167ec2005-06-23 00:07:39 -07001963 map = alloc_remap(pgdat->node_id, size);
1964 if (!map)
1965 map = alloc_bootmem_node(pgdat, size);
1966 pgdat->node_mem_map = map;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001967 }
Andy Whitcroftd41dee32005-06-23 00:07:54 -07001968#ifdef CONFIG_FLATMEM
Linus Torvalds1da177e2005-04-16 15:20:36 -07001969 /*
1970 * With no DISCONTIG, the global mem_map is just set as node 0's
1971 */
1972 if (pgdat == NODE_DATA(0))
1973 mem_map = NODE_DATA(0)->node_mem_map;
1974#endif
Andy Whitcroftd41dee32005-06-23 00:07:54 -07001975#endif /* CONFIG_FLAT_NODE_MEM_MAP */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001976}
1977
1978void __init free_area_init_node(int nid, struct pglist_data *pgdat,
1979 unsigned long *zones_size, unsigned long node_start_pfn,
1980 unsigned long *zholes_size)
1981{
1982 pgdat->node_id = nid;
1983 pgdat->node_start_pfn = node_start_pfn;
1984 calculate_zone_totalpages(pgdat, zones_size, zholes_size);
1985
1986 alloc_node_mem_map(pgdat);
1987
1988 free_area_init_core(pgdat, zones_size, zholes_size);
1989}
1990
Dave Hansen93b75042005-06-23 00:07:47 -07001991#ifndef CONFIG_NEED_MULTIPLE_NODES
Linus Torvalds1da177e2005-04-16 15:20:36 -07001992static bootmem_data_t contig_bootmem_data;
1993struct pglist_data contig_page_data = { .bdata = &contig_bootmem_data };
1994
1995EXPORT_SYMBOL(contig_page_data);
Dave Hansen93b75042005-06-23 00:07:47 -07001996#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07001997
1998void __init free_area_init(unsigned long *zones_size)
1999{
Dave Hansen93b75042005-06-23 00:07:47 -07002000 free_area_init_node(0, NODE_DATA(0), zones_size,
Linus Torvalds1da177e2005-04-16 15:20:36 -07002001 __pa(PAGE_OFFSET) >> PAGE_SHIFT, NULL);
2002}
Linus Torvalds1da177e2005-04-16 15:20:36 -07002003
2004#ifdef CONFIG_PROC_FS
2005
2006#include <linux/seq_file.h>
2007
2008static void *frag_start(struct seq_file *m, loff_t *pos)
2009{
2010 pg_data_t *pgdat;
2011 loff_t node = *pos;
2012
2013 for (pgdat = pgdat_list; pgdat && node; pgdat = pgdat->pgdat_next)
2014 --node;
2015
2016 return pgdat;
2017}
2018
2019static void *frag_next(struct seq_file *m, void *arg, loff_t *pos)
2020{
2021 pg_data_t *pgdat = (pg_data_t *)arg;
2022
2023 (*pos)++;
2024 return pgdat->pgdat_next;
2025}
2026
2027static void frag_stop(struct seq_file *m, void *arg)
2028{
2029}
2030
2031/*
2032 * This walks the free areas for each zone.
2033 */
2034static int frag_show(struct seq_file *m, void *arg)
2035{
2036 pg_data_t *pgdat = (pg_data_t *)arg;
2037 struct zone *zone;
2038 struct zone *node_zones = pgdat->node_zones;
2039 unsigned long flags;
2040 int order;
2041
2042 for (zone = node_zones; zone - node_zones < MAX_NR_ZONES; ++zone) {
2043 if (!zone->present_pages)
2044 continue;
2045
2046 spin_lock_irqsave(&zone->lock, flags);
2047 seq_printf(m, "Node %d, zone %8s ", pgdat->node_id, zone->name);
2048 for (order = 0; order < MAX_ORDER; ++order)
2049 seq_printf(m, "%6lu ", zone->free_area[order].nr_free);
2050 spin_unlock_irqrestore(&zone->lock, flags);
2051 seq_putc(m, '\n');
2052 }
2053 return 0;
2054}
2055
2056struct seq_operations fragmentation_op = {
2057 .start = frag_start,
2058 .next = frag_next,
2059 .stop = frag_stop,
2060 .show = frag_show,
2061};
2062
Nikita Danilov295ab932005-06-21 17:14:38 -07002063/*
2064 * Output information about zones in @pgdat.
2065 */
2066static int zoneinfo_show(struct seq_file *m, void *arg)
2067{
2068 pg_data_t *pgdat = arg;
2069 struct zone *zone;
2070 struct zone *node_zones = pgdat->node_zones;
2071 unsigned long flags;
2072
2073 for (zone = node_zones; zone - node_zones < MAX_NR_ZONES; zone++) {
2074 int i;
2075
2076 if (!zone->present_pages)
2077 continue;
2078
2079 spin_lock_irqsave(&zone->lock, flags);
2080 seq_printf(m, "Node %d, zone %8s", pgdat->node_id, zone->name);
2081 seq_printf(m,
2082 "\n pages free %lu"
2083 "\n min %lu"
2084 "\n low %lu"
2085 "\n high %lu"
2086 "\n active %lu"
2087 "\n inactive %lu"
2088 "\n scanned %lu (a: %lu i: %lu)"
2089 "\n spanned %lu"
2090 "\n present %lu",
2091 zone->free_pages,
2092 zone->pages_min,
2093 zone->pages_low,
2094 zone->pages_high,
2095 zone->nr_active,
2096 zone->nr_inactive,
2097 zone->pages_scanned,
2098 zone->nr_scan_active, zone->nr_scan_inactive,
2099 zone->spanned_pages,
2100 zone->present_pages);
2101 seq_printf(m,
2102 "\n protection: (%lu",
2103 zone->lowmem_reserve[0]);
2104 for (i = 1; i < ARRAY_SIZE(zone->lowmem_reserve); i++)
2105 seq_printf(m, ", %lu", zone->lowmem_reserve[i]);
2106 seq_printf(m,
2107 ")"
2108 "\n pagesets");
2109 for (i = 0; i < ARRAY_SIZE(zone->pageset); i++) {
2110 struct per_cpu_pageset *pageset;
2111 int j;
2112
Christoph Lametere7c8d5c2005-06-21 17:14:47 -07002113 pageset = zone_pcp(zone, i);
Nikita Danilov295ab932005-06-21 17:14:38 -07002114 for (j = 0; j < ARRAY_SIZE(pageset->pcp); j++) {
2115 if (pageset->pcp[j].count)
2116 break;
2117 }
2118 if (j == ARRAY_SIZE(pageset->pcp))
2119 continue;
2120 for (j = 0; j < ARRAY_SIZE(pageset->pcp); j++) {
2121 seq_printf(m,
2122 "\n cpu: %i pcp: %i"
2123 "\n count: %i"
2124 "\n low: %i"
2125 "\n high: %i"
2126 "\n batch: %i",
2127 i, j,
2128 pageset->pcp[j].count,
2129 pageset->pcp[j].low,
2130 pageset->pcp[j].high,
2131 pageset->pcp[j].batch);
2132 }
2133#ifdef CONFIG_NUMA
2134 seq_printf(m,
2135 "\n numa_hit: %lu"
2136 "\n numa_miss: %lu"
2137 "\n numa_foreign: %lu"
2138 "\n interleave_hit: %lu"
2139 "\n local_node: %lu"
2140 "\n other_node: %lu",
2141 pageset->numa_hit,
2142 pageset->numa_miss,
2143 pageset->numa_foreign,
2144 pageset->interleave_hit,
2145 pageset->local_node,
2146 pageset->other_node);
2147#endif
2148 }
2149 seq_printf(m,
2150 "\n all_unreclaimable: %u"
2151 "\n prev_priority: %i"
2152 "\n temp_priority: %i"
2153 "\n start_pfn: %lu",
2154 zone->all_unreclaimable,
2155 zone->prev_priority,
2156 zone->temp_priority,
2157 zone->zone_start_pfn);
2158 spin_unlock_irqrestore(&zone->lock, flags);
2159 seq_putc(m, '\n');
2160 }
2161 return 0;
2162}
2163
2164struct seq_operations zoneinfo_op = {
2165 .start = frag_start, /* iterate over all zones. The same as in
2166 * fragmentation. */
2167 .next = frag_next,
2168 .stop = frag_stop,
2169 .show = zoneinfo_show,
2170};
2171
Linus Torvalds1da177e2005-04-16 15:20:36 -07002172static char *vmstat_text[] = {
2173 "nr_dirty",
2174 "nr_writeback",
2175 "nr_unstable",
2176 "nr_page_table_pages",
2177 "nr_mapped",
2178 "nr_slab",
2179
2180 "pgpgin",
2181 "pgpgout",
2182 "pswpin",
2183 "pswpout",
2184 "pgalloc_high",
2185
2186 "pgalloc_normal",
2187 "pgalloc_dma",
2188 "pgfree",
2189 "pgactivate",
2190 "pgdeactivate",
2191
2192 "pgfault",
2193 "pgmajfault",
2194 "pgrefill_high",
2195 "pgrefill_normal",
2196 "pgrefill_dma",
2197
2198 "pgsteal_high",
2199 "pgsteal_normal",
2200 "pgsteal_dma",
2201 "pgscan_kswapd_high",
2202 "pgscan_kswapd_normal",
2203
2204 "pgscan_kswapd_dma",
2205 "pgscan_direct_high",
2206 "pgscan_direct_normal",
2207 "pgscan_direct_dma",
2208 "pginodesteal",
2209
2210 "slabs_scanned",
2211 "kswapd_steal",
2212 "kswapd_inodesteal",
2213 "pageoutrun",
2214 "allocstall",
2215
2216 "pgrotated",
KAMEZAWA Hiroyukiedfbe2b2005-05-01 08:58:37 -07002217 "nr_bounce",
Linus Torvalds1da177e2005-04-16 15:20:36 -07002218};
2219
2220static void *vmstat_start(struct seq_file *m, loff_t *pos)
2221{
2222 struct page_state *ps;
2223
2224 if (*pos >= ARRAY_SIZE(vmstat_text))
2225 return NULL;
2226
2227 ps = kmalloc(sizeof(*ps), GFP_KERNEL);
2228 m->private = ps;
2229 if (!ps)
2230 return ERR_PTR(-ENOMEM);
2231 get_full_page_state(ps);
2232 ps->pgpgin /= 2; /* sectors -> kbytes */
2233 ps->pgpgout /= 2;
2234 return (unsigned long *)ps + *pos;
2235}
2236
2237static void *vmstat_next(struct seq_file *m, void *arg, loff_t *pos)
2238{
2239 (*pos)++;
2240 if (*pos >= ARRAY_SIZE(vmstat_text))
2241 return NULL;
2242 return (unsigned long *)m->private + *pos;
2243}
2244
2245static int vmstat_show(struct seq_file *m, void *arg)
2246{
2247 unsigned long *l = arg;
2248 unsigned long off = l - (unsigned long *)m->private;
2249
2250 seq_printf(m, "%s %lu\n", vmstat_text[off], *l);
2251 return 0;
2252}
2253
2254static void vmstat_stop(struct seq_file *m, void *arg)
2255{
2256 kfree(m->private);
2257 m->private = NULL;
2258}
2259
2260struct seq_operations vmstat_op = {
2261 .start = vmstat_start,
2262 .next = vmstat_next,
2263 .stop = vmstat_stop,
2264 .show = vmstat_show,
2265};
2266
2267#endif /* CONFIG_PROC_FS */
2268
2269#ifdef CONFIG_HOTPLUG_CPU
2270static int page_alloc_cpu_notify(struct notifier_block *self,
2271 unsigned long action, void *hcpu)
2272{
2273 int cpu = (unsigned long)hcpu;
2274 long *count;
2275 unsigned long *src, *dest;
2276
2277 if (action == CPU_DEAD) {
2278 int i;
2279
2280 /* Drain local pagecache count. */
2281 count = &per_cpu(nr_pagecache_local, cpu);
2282 atomic_add(*count, &nr_pagecache);
2283 *count = 0;
2284 local_irq_disable();
2285 __drain_pages(cpu);
2286
2287 /* Add dead cpu's page_states to our own. */
2288 dest = (unsigned long *)&__get_cpu_var(page_states);
2289 src = (unsigned long *)&per_cpu(page_states, cpu);
2290
2291 for (i = 0; i < sizeof(struct page_state)/sizeof(unsigned long);
2292 i++) {
2293 dest[i] += src[i];
2294 src[i] = 0;
2295 }
2296
2297 local_irq_enable();
2298 }
2299 return NOTIFY_OK;
2300}
2301#endif /* CONFIG_HOTPLUG_CPU */
2302
2303void __init page_alloc_init(void)
2304{
2305 hotcpu_notifier(page_alloc_cpu_notify, 0);
2306}
2307
2308/*
2309 * setup_per_zone_lowmem_reserve - called whenever
2310 * sysctl_lower_zone_reserve_ratio changes. Ensures that each zone
2311 * has a correct pages reserved value, so an adequate number of
2312 * pages are left in the zone after a successful __alloc_pages().
2313 */
2314static void setup_per_zone_lowmem_reserve(void)
2315{
2316 struct pglist_data *pgdat;
2317 int j, idx;
2318
2319 for_each_pgdat(pgdat) {
2320 for (j = 0; j < MAX_NR_ZONES; j++) {
2321 struct zone *zone = pgdat->node_zones + j;
2322 unsigned long present_pages = zone->present_pages;
2323
2324 zone->lowmem_reserve[j] = 0;
2325
2326 for (idx = j-1; idx >= 0; idx--) {
2327 struct zone *lower_zone;
2328
2329 if (sysctl_lowmem_reserve_ratio[idx] < 1)
2330 sysctl_lowmem_reserve_ratio[idx] = 1;
2331
2332 lower_zone = pgdat->node_zones + idx;
2333 lower_zone->lowmem_reserve[j] = present_pages /
2334 sysctl_lowmem_reserve_ratio[idx];
2335 present_pages += lower_zone->present_pages;
2336 }
2337 }
2338 }
2339}
2340
2341/*
2342 * setup_per_zone_pages_min - called when min_free_kbytes changes. Ensures
2343 * that the pages_{min,low,high} values for each zone are set correctly
2344 * with respect to min_free_kbytes.
2345 */
2346static void setup_per_zone_pages_min(void)
2347{
2348 unsigned long pages_min = min_free_kbytes >> (PAGE_SHIFT - 10);
2349 unsigned long lowmem_pages = 0;
2350 struct zone *zone;
2351 unsigned long flags;
2352
2353 /* Calculate total number of !ZONE_HIGHMEM pages */
2354 for_each_zone(zone) {
2355 if (!is_highmem(zone))
2356 lowmem_pages += zone->present_pages;
2357 }
2358
2359 for_each_zone(zone) {
2360 spin_lock_irqsave(&zone->lru_lock, flags);
2361 if (is_highmem(zone)) {
2362 /*
2363 * Often, highmem doesn't need to reserve any pages.
2364 * But the pages_min/low/high values are also used for
2365 * batching up page reclaim activity so we need a
2366 * decent value here.
2367 */
2368 int min_pages;
2369
2370 min_pages = zone->present_pages / 1024;
2371 if (min_pages < SWAP_CLUSTER_MAX)
2372 min_pages = SWAP_CLUSTER_MAX;
2373 if (min_pages > 128)
2374 min_pages = 128;
2375 zone->pages_min = min_pages;
2376 } else {
Nikita Danilov295ab932005-06-21 17:14:38 -07002377 /* if it's a lowmem zone, reserve a number of pages
Linus Torvalds1da177e2005-04-16 15:20:36 -07002378 * proportionate to the zone's size.
2379 */
Nikita Danilov295ab932005-06-21 17:14:38 -07002380 zone->pages_min = (pages_min * zone->present_pages) /
Linus Torvalds1da177e2005-04-16 15:20:36 -07002381 lowmem_pages;
2382 }
2383
2384 /*
2385 * When interpreting these watermarks, just keep in mind that:
2386 * zone->pages_min == (zone->pages_min * 4) / 4;
2387 */
2388 zone->pages_low = (zone->pages_min * 5) / 4;
2389 zone->pages_high = (zone->pages_min * 6) / 4;
2390 spin_unlock_irqrestore(&zone->lru_lock, flags);
2391 }
2392}
2393
2394/*
2395 * Initialise min_free_kbytes.
2396 *
2397 * For small machines we want it small (128k min). For large machines
2398 * we want it large (64MB max). But it is not linear, because network
2399 * bandwidth does not increase linearly with machine size. We use
2400 *
2401 * min_free_kbytes = 4 * sqrt(lowmem_kbytes), for better accuracy:
2402 * min_free_kbytes = sqrt(lowmem_kbytes * 16)
2403 *
2404 * which yields
2405 *
2406 * 16MB: 512k
2407 * 32MB: 724k
2408 * 64MB: 1024k
2409 * 128MB: 1448k
2410 * 256MB: 2048k
2411 * 512MB: 2896k
2412 * 1024MB: 4096k
2413 * 2048MB: 5792k
2414 * 4096MB: 8192k
2415 * 8192MB: 11584k
2416 * 16384MB: 16384k
2417 */
2418static int __init init_per_zone_pages_min(void)
2419{
2420 unsigned long lowmem_kbytes;
2421
2422 lowmem_kbytes = nr_free_buffer_pages() * (PAGE_SIZE >> 10);
2423
2424 min_free_kbytes = int_sqrt(lowmem_kbytes * 16);
2425 if (min_free_kbytes < 128)
2426 min_free_kbytes = 128;
2427 if (min_free_kbytes > 65536)
2428 min_free_kbytes = 65536;
2429 setup_per_zone_pages_min();
2430 setup_per_zone_lowmem_reserve();
2431 return 0;
2432}
2433module_init(init_per_zone_pages_min)
2434
2435/*
2436 * min_free_kbytes_sysctl_handler - just a wrapper around proc_dointvec() so
2437 * that we can call two helper functions whenever min_free_kbytes
2438 * changes.
2439 */
2440int min_free_kbytes_sysctl_handler(ctl_table *table, int write,
2441 struct file *file, void __user *buffer, size_t *length, loff_t *ppos)
2442{
2443 proc_dointvec(table, write, file, buffer, length, ppos);
2444 setup_per_zone_pages_min();
2445 return 0;
2446}
2447
2448/*
2449 * lowmem_reserve_ratio_sysctl_handler - just a wrapper around
2450 * proc_dointvec() so that we can call setup_per_zone_lowmem_reserve()
2451 * whenever sysctl_lowmem_reserve_ratio changes.
2452 *
2453 * The reserve ratio obviously has absolutely no relation with the
2454 * pages_min watermarks. The lowmem reserve ratio can only make sense
2455 * if in function of the boot time zone sizes.
2456 */
2457int lowmem_reserve_ratio_sysctl_handler(ctl_table *table, int write,
2458 struct file *file, void __user *buffer, size_t *length, loff_t *ppos)
2459{
2460 proc_dointvec_minmax(table, write, file, buffer, length, ppos);
2461 setup_per_zone_lowmem_reserve();
2462 return 0;
2463}
2464
2465__initdata int hashdist = HASHDIST_DEFAULT;
2466
2467#ifdef CONFIG_NUMA
2468static int __init set_hashdist(char *str)
2469{
2470 if (!str)
2471 return 0;
2472 hashdist = simple_strtoul(str, &str, 0);
2473 return 1;
2474}
2475__setup("hashdist=", set_hashdist);
2476#endif
2477
2478/*
2479 * allocate a large system hash table from bootmem
2480 * - it is assumed that the hash table must contain an exact power-of-2
2481 * quantity of entries
2482 * - limit is the number of hash buckets, not the total allocation size
2483 */
2484void *__init alloc_large_system_hash(const char *tablename,
2485 unsigned long bucketsize,
2486 unsigned long numentries,
2487 int scale,
2488 int flags,
2489 unsigned int *_hash_shift,
2490 unsigned int *_hash_mask,
2491 unsigned long limit)
2492{
2493 unsigned long long max = limit;
2494 unsigned long log2qty, size;
2495 void *table = NULL;
2496
2497 /* allow the kernel cmdline to have a say */
2498 if (!numentries) {
2499 /* round applicable memory size up to nearest megabyte */
2500 numentries = (flags & HASH_HIGHMEM) ? nr_all_pages : nr_kernel_pages;
2501 numentries += (1UL << (20 - PAGE_SHIFT)) - 1;
2502 numentries >>= 20 - PAGE_SHIFT;
2503 numentries <<= 20 - PAGE_SHIFT;
2504
2505 /* limit to 1 bucket per 2^scale bytes of low memory */
2506 if (scale > PAGE_SHIFT)
2507 numentries >>= (scale - PAGE_SHIFT);
2508 else
2509 numentries <<= (PAGE_SHIFT - scale);
2510 }
2511 /* rounded up to nearest power of 2 in size */
2512 numentries = 1UL << (long_log2(numentries) + 1);
2513
2514 /* limit allocation size to 1/16 total memory by default */
2515 if (max == 0) {
2516 max = ((unsigned long long)nr_all_pages << PAGE_SHIFT) >> 4;
2517 do_div(max, bucketsize);
2518 }
2519
2520 if (numentries > max)
2521 numentries = max;
2522
2523 log2qty = long_log2(numentries);
2524
2525 do {
2526 size = bucketsize << log2qty;
2527 if (flags & HASH_EARLY)
2528 table = alloc_bootmem(size);
2529 else if (hashdist)
2530 table = __vmalloc(size, GFP_ATOMIC, PAGE_KERNEL);
2531 else {
2532 unsigned long order;
2533 for (order = 0; ((1UL << order) << PAGE_SHIFT) < size; order++)
2534 ;
2535 table = (void*) __get_free_pages(GFP_ATOMIC, order);
2536 }
2537 } while (!table && size > PAGE_SIZE && --log2qty);
2538
2539 if (!table)
2540 panic("Failed to allocate %s hash table\n", tablename);
2541
2542 printk("%s hash table entries: %d (order: %d, %lu bytes)\n",
2543 tablename,
2544 (1U << log2qty),
2545 long_log2(size) - PAGE_SHIFT,
2546 size);
2547
2548 if (_hash_shift)
2549 *_hash_shift = log2qty;
2550 if (_hash_mask)
2551 *_hash_mask = (1 << log2qty) - 1;
2552
2553 return table;
2554}