Contents of /alx-src/tags/kernel26-2.6.12-alx-r9/mm/page_alloc.c
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Wed Mar 4 11:03:09 2009 UTC (15 years, 6 months ago) by niro
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Wed Mar 4 11:03:09 2009 UTC (15 years, 6 months ago) by niro
File MIME type: text/plain
File size: 56235 byte(s)
Tag kernel26-2.6.12-alx-r9
1 | /* |
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 | */ |
45 | nodemask_t node_online_map = { { [0] = 1UL } }; |
46 | EXPORT_SYMBOL(node_online_map); |
47 | nodemask_t node_possible_map = NODE_MASK_ALL; |
48 | EXPORT_SYMBOL(node_possible_map); |
49 | struct pglist_data *pgdat_list; |
50 | unsigned long totalram_pages; |
51 | unsigned long totalhigh_pages; |
52 | long 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 | */ |
62 | int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES-1] = { 256, 32 }; |
63 | |
64 | EXPORT_SYMBOL(totalram_pages); |
65 | EXPORT_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 | */ |
71 | struct zone *zone_table[1 << (ZONES_SHIFT + NODES_SHIFT)]; |
72 | EXPORT_SYMBOL(zone_table); |
73 | |
74 | static char *zone_names[MAX_NR_ZONES] = { "DMA", "Normal", "HighMem" }; |
75 | int min_free_kbytes = 1024; |
76 | |
77 | unsigned long __initdata nr_kernel_pages; |
78 | unsigned long __initdata nr_all_pages; |
79 | |
80 | /* |
81 | * Temporary debugging check for pages not lying within a given zone. |
82 | */ |
83 | static 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 | |
98 | static 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"); |
108 | page->flags &= ~(1 << PG_private | |
109 | 1 << PG_locked | |
110 | 1 << PG_lru | |
111 | 1 << PG_active | |
112 | 1 << PG_dirty | |
113 | 1 << PG_swapcache | |
114 | 1 << PG_writeback); |
115 | set_page_count(page, 0); |
116 | reset_page_mapcount(page); |
117 | page->mapping = NULL; |
118 | tainted |= TAINT_BAD_PAGE; |
119 | } |
120 | |
121 | #ifndef CONFIG_HUGETLB_PAGE |
122 | #define prep_compound_page(page, order) do { } while (0) |
123 | #define destroy_compound_page(page, order) do { } while (0) |
124 | #else |
125 | /* |
126 | * Higher-order pages are called "compound pages". They are structured thusly: |
127 | * |
128 | * The first PAGE_SIZE page is called the "head page". |
129 | * |
130 | * The remaining PAGE_SIZE pages are called "tail pages". |
131 | * |
132 | * All pages have PG_compound set. All pages have their ->private pointing at |
133 | * the head page (even the head page has this). |
134 | * |
135 | * The first tail page's ->mapping, if non-zero, holds the address of the |
136 | * compound page's put_page() function. |
137 | * |
138 | * The order of the allocation is stored in the first tail page's ->index |
139 | * This is only for debug at present. This usage means that zero-order pages |
140 | * may not be compound. |
141 | */ |
142 | static void prep_compound_page(struct page *page, unsigned long order) |
143 | { |
144 | int i; |
145 | int nr_pages = 1 << order; |
146 | |
147 | page[1].mapping = NULL; |
148 | page[1].index = order; |
149 | for (i = 0; i < nr_pages; i++) { |
150 | struct page *p = page + i; |
151 | |
152 | SetPageCompound(p); |
153 | p->private = (unsigned long)page; |
154 | } |
155 | } |
156 | |
157 | static void destroy_compound_page(struct page *page, unsigned long order) |
158 | { |
159 | int i; |
160 | int nr_pages = 1 << order; |
161 | |
162 | if (!PageCompound(page)) |
163 | return; |
164 | |
165 | if (page[1].index != order) |
166 | bad_page(__FUNCTION__, page); |
167 | |
168 | for (i = 0; i < nr_pages; i++) { |
169 | struct page *p = page + i; |
170 | |
171 | if (!PageCompound(p)) |
172 | bad_page(__FUNCTION__, page); |
173 | if (p->private != (unsigned long)page) |
174 | bad_page(__FUNCTION__, page); |
175 | ClearPageCompound(p); |
176 | } |
177 | } |
178 | #endif /* CONFIG_HUGETLB_PAGE */ |
179 | |
180 | /* |
181 | * function for dealing with page's order in buddy system. |
182 | * zone->lock is already acquired when we use these. |
183 | * So, we don't need atomic page->flags operations here. |
184 | */ |
185 | static inline unsigned long page_order(struct page *page) { |
186 | return page->private; |
187 | } |
188 | |
189 | static inline void set_page_order(struct page *page, int order) { |
190 | page->private = order; |
191 | __SetPagePrivate(page); |
192 | } |
193 | |
194 | static inline void rmv_page_order(struct page *page) |
195 | { |
196 | __ClearPagePrivate(page); |
197 | page->private = 0; |
198 | } |
199 | |
200 | /* |
201 | * Locate the struct page for both the matching buddy in our |
202 | * pair (buddy1) and the combined O(n+1) page they form (page). |
203 | * |
204 | * 1) Any buddy B1 will have an order O twin B2 which satisfies |
205 | * the following equation: |
206 | * B2 = B1 ^ (1 << O) |
207 | * For example, if the starting buddy (buddy2) is #8 its order |
208 | * 1 buddy is #10: |
209 | * B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10 |
210 | * |
211 | * 2) Any buddy B will have an order O+1 parent P which |
212 | * satisfies the following equation: |
213 | * P = B & ~(1 << O) |
214 | * |
215 | * Assumption: *_mem_map is contigious at least up to MAX_ORDER |
216 | */ |
217 | static inline struct page * |
218 | __page_find_buddy(struct page *page, unsigned long page_idx, unsigned int order) |
219 | { |
220 | unsigned long buddy_idx = page_idx ^ (1 << order); |
221 | |
222 | return page + (buddy_idx - page_idx); |
223 | } |
224 | |
225 | static inline unsigned long |
226 | __find_combined_index(unsigned long page_idx, unsigned int order) |
227 | { |
228 | return (page_idx & ~(1 << order)); |
229 | } |
230 | |
231 | /* |
232 | * This function checks whether a page is free && is the buddy |
233 | * we can do coalesce a page and its buddy if |
234 | * (a) the buddy is free && |
235 | * (b) the buddy is on the buddy system && |
236 | * (c) a page and its buddy have the same order. |
237 | * for recording page's order, we use page->private and PG_private. |
238 | * |
239 | */ |
240 | static inline int page_is_buddy(struct page *page, int order) |
241 | { |
242 | if (PagePrivate(page) && |
243 | (page_order(page) == order) && |
244 | !PageReserved(page) && |
245 | page_count(page) == 0) |
246 | return 1; |
247 | return 0; |
248 | } |
249 | |
250 | /* |
251 | * Freeing function for a buddy system allocator. |
252 | * |
253 | * The concept of a buddy system is to maintain direct-mapped table |
254 | * (containing bit values) for memory blocks of various "orders". |
255 | * The bottom level table contains the map for the smallest allocatable |
256 | * units of memory (here, pages), and each level above it describes |
257 | * pairs of units from the levels below, hence, "buddies". |
258 | * At a high level, all that happens here is marking the table entry |
259 | * at the bottom level available, and propagating the changes upward |
260 | * as necessary, plus some accounting needed to play nicely with other |
261 | * parts of the VM system. |
262 | * At each level, we keep a list of pages, which are heads of continuous |
263 | * free pages of length of (1 << order) and marked with PG_Private.Page's |
264 | * order is recorded in page->private field. |
265 | * So when we are allocating or freeing one, we can derive the state of the |
266 | * other. That is, if we allocate a small block, and both were |
267 | * free, the remainder of the region must be split into blocks. |
268 | * If a block is freed, and its buddy is also free, then this |
269 | * triggers coalescing into a block of larger size. |
270 | * |
271 | * -- wli |
272 | */ |
273 | |
274 | static inline void __free_pages_bulk (struct page *page, |
275 | struct zone *zone, unsigned int order) |
276 | { |
277 | unsigned long page_idx; |
278 | int order_size = 1 << order; |
279 | |
280 | if (unlikely(order)) |
281 | destroy_compound_page(page, order); |
282 | |
283 | page_idx = page_to_pfn(page) & ((1 << MAX_ORDER) - 1); |
284 | |
285 | BUG_ON(page_idx & (order_size - 1)); |
286 | BUG_ON(bad_range(zone, page)); |
287 | |
288 | zone->free_pages += order_size; |
289 | while (order < MAX_ORDER-1) { |
290 | unsigned long combined_idx; |
291 | struct free_area *area; |
292 | struct page *buddy; |
293 | |
294 | combined_idx = __find_combined_index(page_idx, order); |
295 | buddy = __page_find_buddy(page, page_idx, order); |
296 | |
297 | if (bad_range(zone, buddy)) |
298 | break; |
299 | if (!page_is_buddy(buddy, order)) |
300 | break; /* Move the buddy up one level. */ |
301 | list_del(&buddy->lru); |
302 | area = zone->free_area + order; |
303 | area->nr_free--; |
304 | rmv_page_order(buddy); |
305 | page = page + (combined_idx - page_idx); |
306 | page_idx = combined_idx; |
307 | order++; |
308 | } |
309 | set_page_order(page, order); |
310 | list_add(&page->lru, &zone->free_area[order].free_list); |
311 | zone->free_area[order].nr_free++; |
312 | } |
313 | |
314 | static inline void free_pages_check(const char *function, struct page *page) |
315 | { |
316 | if ( page_mapcount(page) || |
317 | page->mapping != NULL || |
318 | page_count(page) != 0 || |
319 | (page->flags & ( |
320 | 1 << PG_lru | |
321 | 1 << PG_private | |
322 | 1 << PG_locked | |
323 | 1 << PG_active | |
324 | 1 << PG_reclaim | |
325 | 1 << PG_slab | |
326 | 1 << PG_swapcache | |
327 | 1 << PG_writeback ))) |
328 | bad_page(function, page); |
329 | if (PageDirty(page)) |
330 | ClearPageDirty(page); |
331 | } |
332 | |
333 | /* |
334 | * Frees a list of pages. |
335 | * Assumes all pages on list are in same zone, and of same order. |
336 | * count is the number of pages to free, or 0 for all on the list. |
337 | * |
338 | * If the zone was previously in an "all pages pinned" state then look to |
339 | * see if this freeing clears that state. |
340 | * |
341 | * And clear the zone's pages_scanned counter, to hold off the "all pages are |
342 | * pinned" detection logic. |
343 | */ |
344 | static int |
345 | free_pages_bulk(struct zone *zone, int count, |
346 | struct list_head *list, unsigned int order) |
347 | { |
348 | unsigned long flags; |
349 | struct page *page = NULL; |
350 | int ret = 0; |
351 | |
352 | spin_lock_irqsave(&zone->lock, flags); |
353 | zone->all_unreclaimable = 0; |
354 | zone->pages_scanned = 0; |
355 | while (!list_empty(list) && count--) { |
356 | page = list_entry(list->prev, struct page, lru); |
357 | /* have to delete it as __free_pages_bulk list manipulates */ |
358 | list_del(&page->lru); |
359 | __free_pages_bulk(page, zone, order); |
360 | ret++; |
361 | } |
362 | spin_unlock_irqrestore(&zone->lock, flags); |
363 | return ret; |
364 | } |
365 | |
366 | void __free_pages_ok(struct page *page, unsigned int order) |
367 | { |
368 | LIST_HEAD(list); |
369 | int i; |
370 | |
371 | arch_free_page(page, order); |
372 | |
373 | mod_page_state(pgfree, 1 << order); |
374 | |
375 | #ifndef CONFIG_MMU |
376 | if (order > 0) |
377 | for (i = 1 ; i < (1 << order) ; ++i) |
378 | __put_page(page + i); |
379 | #endif |
380 | |
381 | for (i = 0 ; i < (1 << order) ; ++i) |
382 | free_pages_check(__FUNCTION__, page + i); |
383 | list_add(&page->lru, &list); |
384 | kernel_map_pages(page, 1<<order, 0); |
385 | free_pages_bulk(page_zone(page), 1, &list, order); |
386 | } |
387 | |
388 | |
389 | /* |
390 | * The order of subdivision here is critical for the IO subsystem. |
391 | * Please do not alter this order without good reasons and regression |
392 | * testing. Specifically, as large blocks of memory are subdivided, |
393 | * the order in which smaller blocks are delivered depends on the order |
394 | * they're subdivided in this function. This is the primary factor |
395 | * influencing the order in which pages are delivered to the IO |
396 | * subsystem according to empirical testing, and this is also justified |
397 | * by considering the behavior of a buddy system containing a single |
398 | * large block of memory acted on by a series of small allocations. |
399 | * This behavior is a critical factor in sglist merging's success. |
400 | * |
401 | * -- wli |
402 | */ |
403 | static inline struct page * |
404 | expand(struct zone *zone, struct page *page, |
405 | int low, int high, struct free_area *area) |
406 | { |
407 | unsigned long size = 1 << high; |
408 | |
409 | while (high > low) { |
410 | area--; |
411 | high--; |
412 | size >>= 1; |
413 | BUG_ON(bad_range(zone, &page[size])); |
414 | list_add(&page[size].lru, &area->free_list); |
415 | area->nr_free++; |
416 | set_page_order(&page[size], high); |
417 | } |
418 | return page; |
419 | } |
420 | |
421 | void set_page_refs(struct page *page, int order) |
422 | { |
423 | #ifdef CONFIG_MMU |
424 | set_page_count(page, 1); |
425 | #else |
426 | int i; |
427 | |
428 | /* |
429 | * We need to reference all the pages for this order, otherwise if |
430 | * anyone accesses one of the pages with (get/put) it will be freed. |
431 | * - eg: access_process_vm() |
432 | */ |
433 | for (i = 0; i < (1 << order); i++) |
434 | set_page_count(page + i, 1); |
435 | #endif /* CONFIG_MMU */ |
436 | } |
437 | |
438 | /* |
439 | * This page is about to be returned from the page allocator |
440 | */ |
441 | static void prep_new_page(struct page *page, int order) |
442 | { |
443 | if (page->mapping || page_mapcount(page) || |
444 | (page->flags & ( |
445 | 1 << PG_private | |
446 | 1 << PG_locked | |
447 | 1 << PG_lru | |
448 | 1 << PG_active | |
449 | 1 << PG_dirty | |
450 | 1 << PG_reclaim | |
451 | 1 << PG_swapcache | |
452 | 1 << PG_writeback ))) |
453 | bad_page(__FUNCTION__, page); |
454 | |
455 | page->flags &= ~(1 << PG_uptodate | 1 << PG_error | |
456 | 1 << PG_referenced | 1 << PG_arch_1 | |
457 | 1 << PG_checked | 1 << PG_mappedtodisk); |
458 | page->private = 0; |
459 | set_page_refs(page, order); |
460 | kernel_map_pages(page, 1 << order, 1); |
461 | } |
462 | |
463 | /* |
464 | * Do the hard work of removing an element from the buddy allocator. |
465 | * Call me with the zone->lock already held. |
466 | */ |
467 | static struct page *__rmqueue(struct zone *zone, unsigned int order) |
468 | { |
469 | struct free_area * area; |
470 | unsigned int current_order; |
471 | struct page *page; |
472 | |
473 | for (current_order = order; current_order < MAX_ORDER; ++current_order) { |
474 | area = zone->free_area + current_order; |
475 | if (list_empty(&area->free_list)) |
476 | continue; |
477 | |
478 | page = list_entry(area->free_list.next, struct page, lru); |
479 | list_del(&page->lru); |
480 | rmv_page_order(page); |
481 | area->nr_free--; |
482 | zone->free_pages -= 1UL << order; |
483 | return expand(zone, page, order, current_order, area); |
484 | } |
485 | |
486 | return NULL; |
487 | } |
488 | |
489 | /* |
490 | * Obtain a specified number of elements from the buddy allocator, all under |
491 | * a single hold of the lock, for efficiency. Add them to the supplied list. |
492 | * Returns the number of new pages which were placed at *list. |
493 | */ |
494 | static int rmqueue_bulk(struct zone *zone, unsigned int order, |
495 | unsigned long count, struct list_head *list) |
496 | { |
497 | unsigned long flags; |
498 | int i; |
499 | int allocated = 0; |
500 | struct page *page; |
501 | |
502 | spin_lock_irqsave(&zone->lock, flags); |
503 | for (i = 0; i < count; ++i) { |
504 | page = __rmqueue(zone, order); |
505 | if (page == NULL) |
506 | break; |
507 | allocated++; |
508 | list_add_tail(&page->lru, list); |
509 | } |
510 | spin_unlock_irqrestore(&zone->lock, flags); |
511 | return allocated; |
512 | } |
513 | |
514 | #if defined(CONFIG_PM) || defined(CONFIG_HOTPLUG_CPU) |
515 | static void __drain_pages(unsigned int cpu) |
516 | { |
517 | struct zone *zone; |
518 | int i; |
519 | |
520 | for_each_zone(zone) { |
521 | struct per_cpu_pageset *pset; |
522 | |
523 | pset = &zone->pageset[cpu]; |
524 | for (i = 0; i < ARRAY_SIZE(pset->pcp); i++) { |
525 | struct per_cpu_pages *pcp; |
526 | |
527 | pcp = &pset->pcp[i]; |
528 | pcp->count -= free_pages_bulk(zone, pcp->count, |
529 | &pcp->list, 0); |
530 | } |
531 | } |
532 | } |
533 | #endif /* CONFIG_PM || CONFIG_HOTPLUG_CPU */ |
534 | |
535 | #ifdef CONFIG_PM |
536 | |
537 | void mark_free_pages(struct zone *zone) |
538 | { |
539 | unsigned long zone_pfn, flags; |
540 | int order; |
541 | struct list_head *curr; |
542 | |
543 | if (!zone->spanned_pages) |
544 | return; |
545 | |
546 | spin_lock_irqsave(&zone->lock, flags); |
547 | for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) |
548 | ClearPageNosaveFree(pfn_to_page(zone_pfn + zone->zone_start_pfn)); |
549 | |
550 | for (order = MAX_ORDER - 1; order >= 0; --order) |
551 | list_for_each(curr, &zone->free_area[order].free_list) { |
552 | unsigned long start_pfn, i; |
553 | |
554 | start_pfn = page_to_pfn(list_entry(curr, struct page, lru)); |
555 | |
556 | for (i=0; i < (1<<order); i++) |
557 | SetPageNosaveFree(pfn_to_page(start_pfn+i)); |
558 | } |
559 | spin_unlock_irqrestore(&zone->lock, flags); |
560 | } |
561 | |
562 | /* |
563 | * Spill all of this CPU's per-cpu pages back into the buddy allocator. |
564 | */ |
565 | void drain_local_pages(void) |
566 | { |
567 | unsigned long flags; |
568 | |
569 | local_irq_save(flags); |
570 | __drain_pages(smp_processor_id()); |
571 | local_irq_restore(flags); |
572 | } |
573 | #endif /* CONFIG_PM */ |
574 | |
575 | static void zone_statistics(struct zonelist *zonelist, struct zone *z) |
576 | { |
577 | #ifdef CONFIG_NUMA |
578 | unsigned long flags; |
579 | int cpu; |
580 | pg_data_t *pg = z->zone_pgdat; |
581 | pg_data_t *orig = zonelist->zones[0]->zone_pgdat; |
582 | struct per_cpu_pageset *p; |
583 | |
584 | local_irq_save(flags); |
585 | cpu = smp_processor_id(); |
586 | p = &z->pageset[cpu]; |
587 | if (pg == orig) { |
588 | z->pageset[cpu].numa_hit++; |
589 | } else { |
590 | p->numa_miss++; |
591 | zonelist->zones[0]->pageset[cpu].numa_foreign++; |
592 | } |
593 | if (pg == NODE_DATA(numa_node_id())) |
594 | p->local_node++; |
595 | else |
596 | p->other_node++; |
597 | local_irq_restore(flags); |
598 | #endif |
599 | } |
600 | |
601 | /* |
602 | * Free a 0-order page |
603 | */ |
604 | static void FASTCALL(free_hot_cold_page(struct page *page, int cold)); |
605 | static void fastcall free_hot_cold_page(struct page *page, int cold) |
606 | { |
607 | struct zone *zone = page_zone(page); |
608 | struct per_cpu_pages *pcp; |
609 | unsigned long flags; |
610 | |
611 | arch_free_page(page, 0); |
612 | |
613 | kernel_map_pages(page, 1, 0); |
614 | inc_page_state(pgfree); |
615 | if (PageAnon(page)) |
616 | page->mapping = NULL; |
617 | free_pages_check(__FUNCTION__, page); |
618 | pcp = &zone->pageset[get_cpu()].pcp[cold]; |
619 | local_irq_save(flags); |
620 | if (pcp->count >= pcp->high) |
621 | pcp->count -= free_pages_bulk(zone, pcp->batch, &pcp->list, 0); |
622 | list_add(&page->lru, &pcp->list); |
623 | pcp->count++; |
624 | local_irq_restore(flags); |
625 | put_cpu(); |
626 | } |
627 | |
628 | void fastcall free_hot_page(struct page *page) |
629 | { |
630 | free_hot_cold_page(page, 0); |
631 | } |
632 | |
633 | void fastcall free_cold_page(struct page *page) |
634 | { |
635 | free_hot_cold_page(page, 1); |
636 | } |
637 | |
638 | static inline void prep_zero_page(struct page *page, int order, unsigned int __nocast gfp_flags) |
639 | { |
640 | int i; |
641 | |
642 | BUG_ON((gfp_flags & (__GFP_WAIT | __GFP_HIGHMEM)) == __GFP_HIGHMEM); |
643 | for(i = 0; i < (1 << order); i++) |
644 | clear_highpage(page + i); |
645 | } |
646 | |
647 | /* |
648 | * Really, prep_compound_page() should be called from __rmqueue_bulk(). But |
649 | * we cheat by calling it from here, in the order > 0 path. Saves a branch |
650 | * or two. |
651 | */ |
652 | static struct page * |
653 | buffered_rmqueue(struct zone *zone, int order, unsigned int __nocast gfp_flags) |
654 | { |
655 | unsigned long flags; |
656 | struct page *page = NULL; |
657 | int cold = !!(gfp_flags & __GFP_COLD); |
658 | |
659 | if (order == 0) { |
660 | struct per_cpu_pages *pcp; |
661 | |
662 | pcp = &zone->pageset[get_cpu()].pcp[cold]; |
663 | local_irq_save(flags); |
664 | if (pcp->count <= pcp->low) |
665 | pcp->count += rmqueue_bulk(zone, 0, |
666 | pcp->batch, &pcp->list); |
667 | if (pcp->count) { |
668 | page = list_entry(pcp->list.next, struct page, lru); |
669 | list_del(&page->lru); |
670 | pcp->count--; |
671 | } |
672 | local_irq_restore(flags); |
673 | put_cpu(); |
674 | } |
675 | |
676 | if (page == NULL) { |
677 | spin_lock_irqsave(&zone->lock, flags); |
678 | page = __rmqueue(zone, order); |
679 | spin_unlock_irqrestore(&zone->lock, flags); |
680 | } |
681 | |
682 | if (page != NULL) { |
683 | BUG_ON(bad_range(zone, page)); |
684 | mod_page_state_zone(zone, pgalloc, 1 << order); |
685 | prep_new_page(page, order); |
686 | |
687 | if (gfp_flags & __GFP_ZERO) |
688 | prep_zero_page(page, order, gfp_flags); |
689 | |
690 | if (order && (gfp_flags & __GFP_COMP)) |
691 | prep_compound_page(page, order); |
692 | } |
693 | return page; |
694 | } |
695 | |
696 | /* |
697 | * Return 1 if free pages are above 'mark'. This takes into account the order |
698 | * of the allocation. |
699 | */ |
700 | int zone_watermark_ok(struct zone *z, int order, unsigned long mark, |
701 | int classzone_idx, int can_try_harder, int gfp_high) |
702 | { |
703 | /* free_pages my go negative - that's OK */ |
704 | long min = mark, free_pages = z->free_pages - (1 << order) + 1; |
705 | int o; |
706 | |
707 | if (gfp_high) |
708 | min -= min / 2; |
709 | if (can_try_harder) |
710 | min -= min / 4; |
711 | |
712 | if (free_pages <= min + z->lowmem_reserve[classzone_idx]) |
713 | return 0; |
714 | for (o = 0; o < order; o++) { |
715 | /* At the next order, this order's pages become unavailable */ |
716 | free_pages -= z->free_area[o].nr_free << o; |
717 | |
718 | /* Require fewer higher order pages to be free */ |
719 | min >>= 1; |
720 | |
721 | if (free_pages <= min) |
722 | return 0; |
723 | } |
724 | return 1; |
725 | } |
726 | |
727 | /* |
728 | * This is the 'heart' of the zoned buddy allocator. |
729 | */ |
730 | struct page * fastcall |
731 | __alloc_pages(unsigned int __nocast gfp_mask, unsigned int order, |
732 | struct zonelist *zonelist) |
733 | { |
734 | const int wait = gfp_mask & __GFP_WAIT; |
735 | struct zone **zones, *z; |
736 | struct page *page; |
737 | struct reclaim_state reclaim_state; |
738 | struct task_struct *p = current; |
739 | int i; |
740 | int classzone_idx; |
741 | int do_retry; |
742 | int can_try_harder; |
743 | int did_some_progress; |
744 | |
745 | might_sleep_if(wait); |
746 | |
747 | /* |
748 | * The caller may dip into page reserves a bit more if the caller |
749 | * cannot run direct reclaim, or is the caller has realtime scheduling |
750 | * policy |
751 | */ |
752 | can_try_harder = (unlikely(rt_task(p)) && !in_interrupt()) || !wait; |
753 | |
754 | zones = zonelist->zones; /* the list of zones suitable for gfp_mask */ |
755 | |
756 | if (unlikely(zones[0] == NULL)) { |
757 | /* Should this ever happen?? */ |
758 | return NULL; |
759 | } |
760 | |
761 | classzone_idx = zone_idx(zones[0]); |
762 | |
763 | restart: |
764 | /* Go through the zonelist once, looking for a zone with enough free */ |
765 | for (i = 0; (z = zones[i]) != NULL; i++) { |
766 | |
767 | if (!zone_watermark_ok(z, order, z->pages_low, |
768 | classzone_idx, 0, 0)) |
769 | continue; |
770 | |
771 | if (!cpuset_zone_allowed(z)) |
772 | continue; |
773 | |
774 | page = buffered_rmqueue(z, order, gfp_mask); |
775 | if (page) |
776 | goto got_pg; |
777 | } |
778 | |
779 | for (i = 0; (z = zones[i]) != NULL; i++) |
780 | wakeup_kswapd(z, order); |
781 | |
782 | /* |
783 | * Go through the zonelist again. Let __GFP_HIGH and allocations |
784 | * coming from realtime tasks to go deeper into reserves |
785 | * |
786 | * This is the last chance, in general, before the goto nopage. |
787 | * Ignore cpuset if GFP_ATOMIC (!wait) rather than fail alloc. |
788 | */ |
789 | for (i = 0; (z = zones[i]) != NULL; i++) { |
790 | if (!zone_watermark_ok(z, order, z->pages_min, |
791 | classzone_idx, can_try_harder, |
792 | gfp_mask & __GFP_HIGH)) |
793 | continue; |
794 | |
795 | if (wait && !cpuset_zone_allowed(z)) |
796 | continue; |
797 | |
798 | page = buffered_rmqueue(z, order, gfp_mask); |
799 | if (page) |
800 | goto got_pg; |
801 | } |
802 | |
803 | /* This allocation should allow future memory freeing. */ |
804 | |
805 | if (((p->flags & PF_MEMALLOC) || unlikely(test_thread_flag(TIF_MEMDIE))) |
806 | && !in_interrupt()) { |
807 | if (!(gfp_mask & __GFP_NOMEMALLOC)) { |
808 | /* go through the zonelist yet again, ignoring mins */ |
809 | for (i = 0; (z = zones[i]) != NULL; i++) { |
810 | if (!cpuset_zone_allowed(z)) |
811 | continue; |
812 | page = buffered_rmqueue(z, order, gfp_mask); |
813 | if (page) |
814 | goto got_pg; |
815 | } |
816 | } |
817 | goto nopage; |
818 | } |
819 | |
820 | /* Atomic allocations - we can't balance anything */ |
821 | if (!wait) |
822 | goto nopage; |
823 | |
824 | rebalance: |
825 | cond_resched(); |
826 | |
827 | /* We now go into synchronous reclaim */ |
828 | p->flags |= PF_MEMALLOC; |
829 | reclaim_state.reclaimed_slab = 0; |
830 | p->reclaim_state = &reclaim_state; |
831 | |
832 | did_some_progress = try_to_free_pages(zones, gfp_mask, order); |
833 | |
834 | p->reclaim_state = NULL; |
835 | p->flags &= ~PF_MEMALLOC; |
836 | |
837 | cond_resched(); |
838 | |
839 | if (likely(did_some_progress)) { |
840 | /* |
841 | * Go through the zonelist yet one more time, keep |
842 | * very high watermark here, this is only to catch |
843 | * a parallel oom killing, we must fail if we're still |
844 | * under heavy pressure. |
845 | */ |
846 | for (i = 0; (z = zones[i]) != NULL; i++) { |
847 | if (!zone_watermark_ok(z, order, z->pages_min, |
848 | classzone_idx, can_try_harder, |
849 | gfp_mask & __GFP_HIGH)) |
850 | continue; |
851 | |
852 | if (!cpuset_zone_allowed(z)) |
853 | continue; |
854 | |
855 | page = buffered_rmqueue(z, order, gfp_mask); |
856 | if (page) |
857 | goto got_pg; |
858 | } |
859 | } else if ((gfp_mask & __GFP_FS) && !(gfp_mask & __GFP_NORETRY)) { |
860 | /* |
861 | * Go through the zonelist yet one more time, keep |
862 | * very high watermark here, this is only to catch |
863 | * a parallel oom killing, we must fail if we're still |
864 | * under heavy pressure. |
865 | */ |
866 | for (i = 0; (z = zones[i]) != NULL; i++) { |
867 | if (!zone_watermark_ok(z, order, z->pages_high, |
868 | classzone_idx, 0, 0)) |
869 | continue; |
870 | |
871 | if (!cpuset_zone_allowed(z)) |
872 | continue; |
873 | |
874 | page = buffered_rmqueue(z, order, gfp_mask); |
875 | if (page) |
876 | goto got_pg; |
877 | } |
878 | |
879 | out_of_memory(gfp_mask); |
880 | goto restart; |
881 | } |
882 | |
883 | /* |
884 | * Don't let big-order allocations loop unless the caller explicitly |
885 | * requests that. Wait for some write requests to complete then retry. |
886 | * |
887 | * In this implementation, __GFP_REPEAT means __GFP_NOFAIL for order |
888 | * <= 3, but that may not be true in other implementations. |
889 | */ |
890 | do_retry = 0; |
891 | if (!(gfp_mask & __GFP_NORETRY)) { |
892 | if ((order <= 3) || (gfp_mask & __GFP_REPEAT)) |
893 | do_retry = 1; |
894 | if (gfp_mask & __GFP_NOFAIL) |
895 | do_retry = 1; |
896 | } |
897 | if (do_retry) { |
898 | blk_congestion_wait(WRITE, HZ/50); |
899 | goto rebalance; |
900 | } |
901 | |
902 | nopage: |
903 | if (!(gfp_mask & __GFP_NOWARN) && printk_ratelimit()) { |
904 | printk(KERN_WARNING "%s: page allocation failure." |
905 | " order:%d, mode:0x%x\n", |
906 | p->comm, order, gfp_mask); |
907 | dump_stack(); |
908 | } |
909 | return NULL; |
910 | got_pg: |
911 | zone_statistics(zonelist, z); |
912 | return page; |
913 | } |
914 | |
915 | EXPORT_SYMBOL(__alloc_pages); |
916 | |
917 | /* |
918 | * Common helper functions. |
919 | */ |
920 | fastcall unsigned long __get_free_pages(unsigned int __nocast gfp_mask, unsigned int order) |
921 | { |
922 | struct page * page; |
923 | page = alloc_pages(gfp_mask, order); |
924 | if (!page) |
925 | return 0; |
926 | return (unsigned long) page_address(page); |
927 | } |
928 | |
929 | EXPORT_SYMBOL(__get_free_pages); |
930 | |
931 | fastcall unsigned long get_zeroed_page(unsigned int __nocast gfp_mask) |
932 | { |
933 | struct page * page; |
934 | |
935 | /* |
936 | * get_zeroed_page() returns a 32-bit address, which cannot represent |
937 | * a highmem page |
938 | */ |
939 | BUG_ON(gfp_mask & __GFP_HIGHMEM); |
940 | |
941 | page = alloc_pages(gfp_mask | __GFP_ZERO, 0); |
942 | if (page) |
943 | return (unsigned long) page_address(page); |
944 | return 0; |
945 | } |
946 | |
947 | EXPORT_SYMBOL(get_zeroed_page); |
948 | |
949 | void __pagevec_free(struct pagevec *pvec) |
950 | { |
951 | int i = pagevec_count(pvec); |
952 | |
953 | while (--i >= 0) |
954 | free_hot_cold_page(pvec->pages[i], pvec->cold); |
955 | } |
956 | |
957 | fastcall void __free_pages(struct page *page, unsigned int order) |
958 | { |
959 | if (!PageReserved(page) && put_page_testzero(page)) { |
960 | if (order == 0) |
961 | free_hot_page(page); |
962 | else |
963 | __free_pages_ok(page, order); |
964 | } |
965 | } |
966 | |
967 | EXPORT_SYMBOL(__free_pages); |
968 | |
969 | fastcall void free_pages(unsigned long addr, unsigned int order) |
970 | { |
971 | if (addr != 0) { |
972 | BUG_ON(!virt_addr_valid((void *)addr)); |
973 | __free_pages(virt_to_page((void *)addr), order); |
974 | } |
975 | } |
976 | |
977 | EXPORT_SYMBOL(free_pages); |
978 | |
979 | /* |
980 | * Total amount of free (allocatable) RAM: |
981 | */ |
982 | unsigned int nr_free_pages(void) |
983 | { |
984 | unsigned int sum = 0; |
985 | struct zone *zone; |
986 | |
987 | for_each_zone(zone) |
988 | sum += zone->free_pages; |
989 | |
990 | return sum; |
991 | } |
992 | |
993 | EXPORT_SYMBOL(nr_free_pages); |
994 | |
995 | #ifdef CONFIG_NUMA |
996 | unsigned int nr_free_pages_pgdat(pg_data_t *pgdat) |
997 | { |
998 | unsigned int i, sum = 0; |
999 | |
1000 | for (i = 0; i < MAX_NR_ZONES; i++) |
1001 | sum += pgdat->node_zones[i].free_pages; |
1002 | |
1003 | return sum; |
1004 | } |
1005 | #endif |
1006 | |
1007 | static unsigned int nr_free_zone_pages(int offset) |
1008 | { |
1009 | pg_data_t *pgdat; |
1010 | unsigned int sum = 0; |
1011 | |
1012 | for_each_pgdat(pgdat) { |
1013 | struct zonelist *zonelist = pgdat->node_zonelists + offset; |
1014 | struct zone **zonep = zonelist->zones; |
1015 | struct zone *zone; |
1016 | |
1017 | for (zone = *zonep++; zone; zone = *zonep++) { |
1018 | unsigned long size = zone->present_pages; |
1019 | unsigned long high = zone->pages_high; |
1020 | if (size > high) |
1021 | sum += size - high; |
1022 | } |
1023 | } |
1024 | |
1025 | return sum; |
1026 | } |
1027 | |
1028 | /* |
1029 | * Amount of free RAM allocatable within ZONE_DMA and ZONE_NORMAL |
1030 | */ |
1031 | unsigned int nr_free_buffer_pages(void) |
1032 | { |
1033 | return nr_free_zone_pages(GFP_USER & GFP_ZONEMASK); |
1034 | } |
1035 | |
1036 | /* |
1037 | * Amount of free RAM allocatable within all zones |
1038 | */ |
1039 | unsigned int nr_free_pagecache_pages(void) |
1040 | { |
1041 | return nr_free_zone_pages(GFP_HIGHUSER & GFP_ZONEMASK); |
1042 | } |
1043 | |
1044 | #ifdef CONFIG_HIGHMEM |
1045 | unsigned int nr_free_highpages (void) |
1046 | { |
1047 | pg_data_t *pgdat; |
1048 | unsigned int pages = 0; |
1049 | |
1050 | for_each_pgdat(pgdat) |
1051 | pages += pgdat->node_zones[ZONE_HIGHMEM].free_pages; |
1052 | |
1053 | return pages; |
1054 | } |
1055 | #endif |
1056 | |
1057 | #ifdef CONFIG_NUMA |
1058 | static void show_node(struct zone *zone) |
1059 | { |
1060 | printk("Node %d ", zone->zone_pgdat->node_id); |
1061 | } |
1062 | #else |
1063 | #define show_node(zone) do { } while (0) |
1064 | #endif |
1065 | |
1066 | /* |
1067 | * Accumulate the page_state information across all CPUs. |
1068 | * The result is unavoidably approximate - it can change |
1069 | * during and after execution of this function. |
1070 | */ |
1071 | static DEFINE_PER_CPU(struct page_state, page_states) = {0}; |
1072 | |
1073 | atomic_t nr_pagecache = ATOMIC_INIT(0); |
1074 | EXPORT_SYMBOL(nr_pagecache); |
1075 | #ifdef CONFIG_SMP |
1076 | DEFINE_PER_CPU(long, nr_pagecache_local) = 0; |
1077 | #endif |
1078 | |
1079 | void __get_page_state(struct page_state *ret, int nr) |
1080 | { |
1081 | int cpu = 0; |
1082 | |
1083 | memset(ret, 0, sizeof(*ret)); |
1084 | |
1085 | cpu = first_cpu(cpu_online_map); |
1086 | while (cpu < NR_CPUS) { |
1087 | unsigned long *in, *out, off; |
1088 | |
1089 | in = (unsigned long *)&per_cpu(page_states, cpu); |
1090 | |
1091 | cpu = next_cpu(cpu, cpu_online_map); |
1092 | |
1093 | if (cpu < NR_CPUS) |
1094 | prefetch(&per_cpu(page_states, cpu)); |
1095 | |
1096 | out = (unsigned long *)ret; |
1097 | for (off = 0; off < nr; off++) |
1098 | *out++ += *in++; |
1099 | } |
1100 | } |
1101 | |
1102 | void get_page_state(struct page_state *ret) |
1103 | { |
1104 | int nr; |
1105 | |
1106 | nr = offsetof(struct page_state, GET_PAGE_STATE_LAST); |
1107 | nr /= sizeof(unsigned long); |
1108 | |
1109 | __get_page_state(ret, nr + 1); |
1110 | } |
1111 | |
1112 | void get_full_page_state(struct page_state *ret) |
1113 | { |
1114 | __get_page_state(ret, sizeof(*ret) / sizeof(unsigned long)); |
1115 | } |
1116 | |
1117 | unsigned long __read_page_state(unsigned offset) |
1118 | { |
1119 | unsigned long ret = 0; |
1120 | int cpu; |
1121 | |
1122 | for_each_online_cpu(cpu) { |
1123 | unsigned long in; |
1124 | |
1125 | in = (unsigned long)&per_cpu(page_states, cpu) + offset; |
1126 | ret += *((unsigned long *)in); |
1127 | } |
1128 | return ret; |
1129 | } |
1130 | |
1131 | void __mod_page_state(unsigned offset, unsigned long delta) |
1132 | { |
1133 | unsigned long flags; |
1134 | void* ptr; |
1135 | |
1136 | local_irq_save(flags); |
1137 | ptr = &__get_cpu_var(page_states); |
1138 | *(unsigned long*)(ptr + offset) += delta; |
1139 | local_irq_restore(flags); |
1140 | } |
1141 | |
1142 | EXPORT_SYMBOL(__mod_page_state); |
1143 | |
1144 | void __get_zone_counts(unsigned long *active, unsigned long *inactive, |
1145 | unsigned long *free, struct pglist_data *pgdat) |
1146 | { |
1147 | struct zone *zones = pgdat->node_zones; |
1148 | int i; |
1149 | |
1150 | *active = 0; |
1151 | *inactive = 0; |
1152 | *free = 0; |
1153 | for (i = 0; i < MAX_NR_ZONES; i++) { |
1154 | *active += zones[i].nr_active; |
1155 | *inactive += zones[i].nr_inactive; |
1156 | *free += zones[i].free_pages; |
1157 | } |
1158 | } |
1159 | |
1160 | void get_zone_counts(unsigned long *active, |
1161 | unsigned long *inactive, unsigned long *free) |
1162 | { |
1163 | struct pglist_data *pgdat; |
1164 | |
1165 | *active = 0; |
1166 | *inactive = 0; |
1167 | *free = 0; |
1168 | for_each_pgdat(pgdat) { |
1169 | unsigned long l, m, n; |
1170 | __get_zone_counts(&l, &m, &n, pgdat); |
1171 | *active += l; |
1172 | *inactive += m; |
1173 | *free += n; |
1174 | } |
1175 | } |
1176 | |
1177 | void si_meminfo(struct sysinfo *val) |
1178 | { |
1179 | val->totalram = totalram_pages; |
1180 | val->sharedram = 0; |
1181 | val->freeram = nr_free_pages(); |
1182 | val->bufferram = nr_blockdev_pages(); |
1183 | #ifdef CONFIG_HIGHMEM |
1184 | val->totalhigh = totalhigh_pages; |
1185 | val->freehigh = nr_free_highpages(); |
1186 | #else |
1187 | val->totalhigh = 0; |
1188 | val->freehigh = 0; |
1189 | #endif |
1190 | val->mem_unit = PAGE_SIZE; |
1191 | } |
1192 | |
1193 | EXPORT_SYMBOL(si_meminfo); |
1194 | |
1195 | #ifdef CONFIG_NUMA |
1196 | void si_meminfo_node(struct sysinfo *val, int nid) |
1197 | { |
1198 | pg_data_t *pgdat = NODE_DATA(nid); |
1199 | |
1200 | val->totalram = pgdat->node_present_pages; |
1201 | val->freeram = nr_free_pages_pgdat(pgdat); |
1202 | val->totalhigh = pgdat->node_zones[ZONE_HIGHMEM].present_pages; |
1203 | val->freehigh = pgdat->node_zones[ZONE_HIGHMEM].free_pages; |
1204 | val->mem_unit = PAGE_SIZE; |
1205 | } |
1206 | #endif |
1207 | |
1208 | #define K(x) ((x) << (PAGE_SHIFT-10)) |
1209 | |
1210 | /* |
1211 | * Show free area list (used inside shift_scroll-lock stuff) |
1212 | * We also calculate the percentage fragmentation. We do this by counting the |
1213 | * memory on each free list with the exception of the first item on the list. |
1214 | */ |
1215 | void show_free_areas(void) |
1216 | { |
1217 | struct page_state ps; |
1218 | int cpu, temperature; |
1219 | unsigned long active; |
1220 | unsigned long inactive; |
1221 | unsigned long free; |
1222 | struct zone *zone; |
1223 | |
1224 | for_each_zone(zone) { |
1225 | show_node(zone); |
1226 | printk("%s per-cpu:", zone->name); |
1227 | |
1228 | if (!zone->present_pages) { |
1229 | printk(" empty\n"); |
1230 | continue; |
1231 | } else |
1232 | printk("\n"); |
1233 | |
1234 | for (cpu = 0; cpu < NR_CPUS; ++cpu) { |
1235 | struct per_cpu_pageset *pageset; |
1236 | |
1237 | if (!cpu_possible(cpu)) |
1238 | continue; |
1239 | |
1240 | pageset = zone->pageset + cpu; |
1241 | |
1242 | for (temperature = 0; temperature < 2; temperature++) |
1243 | printk("cpu %d %s: low %d, high %d, batch %d\n", |
1244 | cpu, |
1245 | temperature ? "cold" : "hot", |
1246 | pageset->pcp[temperature].low, |
1247 | pageset->pcp[temperature].high, |
1248 | pageset->pcp[temperature].batch); |
1249 | } |
1250 | } |
1251 | |
1252 | get_page_state(&ps); |
1253 | get_zone_counts(&active, &inactive, &free); |
1254 | |
1255 | printk("\nFree pages: %11ukB (%ukB HighMem)\n", |
1256 | K(nr_free_pages()), |
1257 | K(nr_free_highpages())); |
1258 | |
1259 | printk("Active:%lu inactive:%lu dirty:%lu writeback:%lu " |
1260 | "unstable:%lu free:%u slab:%lu mapped:%lu pagetables:%lu\n", |
1261 | active, |
1262 | inactive, |
1263 | ps.nr_dirty, |
1264 | ps.nr_writeback, |
1265 | ps.nr_unstable, |
1266 | nr_free_pages(), |
1267 | ps.nr_slab, |
1268 | ps.nr_mapped, |
1269 | ps.nr_page_table_pages); |
1270 | |
1271 | for_each_zone(zone) { |
1272 | int i; |
1273 | |
1274 | show_node(zone); |
1275 | printk("%s" |
1276 | " free:%lukB" |
1277 | " min:%lukB" |
1278 | " low:%lukB" |
1279 | " high:%lukB" |
1280 | " active:%lukB" |
1281 | " inactive:%lukB" |
1282 | " present:%lukB" |
1283 | " pages_scanned:%lu" |
1284 | " all_unreclaimable? %s" |
1285 | "\n", |
1286 | zone->name, |
1287 | K(zone->free_pages), |
1288 | K(zone->pages_min), |
1289 | K(zone->pages_low), |
1290 | K(zone->pages_high), |
1291 | K(zone->nr_active), |
1292 | K(zone->nr_inactive), |
1293 | K(zone->present_pages), |
1294 | zone->pages_scanned, |
1295 | (zone->all_unreclaimable ? "yes" : "no") |
1296 | ); |
1297 | printk("lowmem_reserve[]:"); |
1298 | for (i = 0; i < MAX_NR_ZONES; i++) |
1299 | printk(" %lu", zone->lowmem_reserve[i]); |
1300 | printk("\n"); |
1301 | } |
1302 | |
1303 | for_each_zone(zone) { |
1304 | unsigned long nr, flags, order, total = 0; |
1305 | |
1306 | show_node(zone); |
1307 | printk("%s: ", zone->name); |
1308 | if (!zone->present_pages) { |
1309 | printk("empty\n"); |
1310 | continue; |
1311 | } |
1312 | |
1313 | spin_lock_irqsave(&zone->lock, flags); |
1314 | for (order = 0; order < MAX_ORDER; order++) { |
1315 | nr = zone->free_area[order].nr_free; |
1316 | total += nr << order; |
1317 | printk("%lu*%lukB ", nr, K(1UL) << order); |
1318 | } |
1319 | spin_unlock_irqrestore(&zone->lock, flags); |
1320 | printk("= %lukB\n", K(total)); |
1321 | } |
1322 | |
1323 | show_swap_cache_info(); |
1324 | } |
1325 | |
1326 | /* |
1327 | * Builds allocation fallback zone lists. |
1328 | */ |
1329 | static int __init build_zonelists_node(pg_data_t *pgdat, struct zonelist *zonelist, int j, int k) |
1330 | { |
1331 | switch (k) { |
1332 | struct zone *zone; |
1333 | default: |
1334 | BUG(); |
1335 | case ZONE_HIGHMEM: |
1336 | zone = pgdat->node_zones + ZONE_HIGHMEM; |
1337 | if (zone->present_pages) { |
1338 | #ifndef CONFIG_HIGHMEM |
1339 | BUG(); |
1340 | #endif |
1341 | zonelist->zones[j++] = zone; |
1342 | } |
1343 | case ZONE_NORMAL: |
1344 | zone = pgdat->node_zones + ZONE_NORMAL; |
1345 | if (zone->present_pages) |
1346 | zonelist->zones[j++] = zone; |
1347 | case ZONE_DMA: |
1348 | zone = pgdat->node_zones + ZONE_DMA; |
1349 | if (zone->present_pages) |
1350 | zonelist->zones[j++] = zone; |
1351 | } |
1352 | |
1353 | return j; |
1354 | } |
1355 | |
1356 | #ifdef CONFIG_NUMA |
1357 | #define MAX_NODE_LOAD (num_online_nodes()) |
1358 | static int __initdata node_load[MAX_NUMNODES]; |
1359 | /** |
1360 | * find_next_best_node - find the next node that should appear in a given node's fallback list |
1361 | * @node: node whose fallback list we're appending |
1362 | * @used_node_mask: nodemask_t of already used nodes |
1363 | * |
1364 | * We use a number of factors to determine which is the next node that should |
1365 | * appear on a given node's fallback list. The node should not have appeared |
1366 | * already in @node's fallback list, and it should be the next closest node |
1367 | * according to the distance array (which contains arbitrary distance values |
1368 | * from each node to each node in the system), and should also prefer nodes |
1369 | * with no CPUs, since presumably they'll have very little allocation pressure |
1370 | * on them otherwise. |
1371 | * It returns -1 if no node is found. |
1372 | */ |
1373 | static int __init find_next_best_node(int node, nodemask_t *used_node_mask) |
1374 | { |
1375 | int i, n, val; |
1376 | int min_val = INT_MAX; |
1377 | int best_node = -1; |
1378 | |
1379 | for_each_online_node(i) { |
1380 | cpumask_t tmp; |
1381 | |
1382 | /* Start from local node */ |
1383 | n = (node+i) % num_online_nodes(); |
1384 | |
1385 | /* Don't want a node to appear more than once */ |
1386 | if (node_isset(n, *used_node_mask)) |
1387 | continue; |
1388 | |
1389 | /* Use the local node if we haven't already */ |
1390 | if (!node_isset(node, *used_node_mask)) { |
1391 | best_node = node; |
1392 | break; |
1393 | } |
1394 | |
1395 | /* Use the distance array to find the distance */ |
1396 | val = node_distance(node, n); |
1397 | |
1398 | /* Give preference to headless and unused nodes */ |
1399 | tmp = node_to_cpumask(n); |
1400 | if (!cpus_empty(tmp)) |
1401 | val += PENALTY_FOR_NODE_WITH_CPUS; |
1402 | |
1403 | /* Slight preference for less loaded node */ |
1404 | val *= (MAX_NODE_LOAD*MAX_NUMNODES); |
1405 | val += node_load[n]; |
1406 | |
1407 | if (val < min_val) { |
1408 | min_val = val; |
1409 | best_node = n; |
1410 | } |
1411 | } |
1412 | |
1413 | if (best_node >= 0) |
1414 | node_set(best_node, *used_node_mask); |
1415 | |
1416 | return best_node; |
1417 | } |
1418 | |
1419 | static void __init build_zonelists(pg_data_t *pgdat) |
1420 | { |
1421 | int i, j, k, node, local_node; |
1422 | int prev_node, load; |
1423 | struct zonelist *zonelist; |
1424 | nodemask_t used_mask; |
1425 | |
1426 | /* initialize zonelists */ |
1427 | for (i = 0; i < GFP_ZONETYPES; i++) { |
1428 | zonelist = pgdat->node_zonelists + i; |
1429 | zonelist->zones[0] = NULL; |
1430 | } |
1431 | |
1432 | /* NUMA-aware ordering of nodes */ |
1433 | local_node = pgdat->node_id; |
1434 | load = num_online_nodes(); |
1435 | prev_node = local_node; |
1436 | nodes_clear(used_mask); |
1437 | while ((node = find_next_best_node(local_node, &used_mask)) >= 0) { |
1438 | /* |
1439 | * We don't want to pressure a particular node. |
1440 | * So adding penalty to the first node in same |
1441 | * distance group to make it round-robin. |
1442 | */ |
1443 | if (node_distance(local_node, node) != |
1444 | node_distance(local_node, prev_node)) |
1445 | node_load[node] += load; |
1446 | prev_node = node; |
1447 | load--; |
1448 | for (i = 0; i < GFP_ZONETYPES; i++) { |
1449 | zonelist = pgdat->node_zonelists + i; |
1450 | for (j = 0; zonelist->zones[j] != NULL; j++); |
1451 | |
1452 | k = ZONE_NORMAL; |
1453 | if (i & __GFP_HIGHMEM) |
1454 | k = ZONE_HIGHMEM; |
1455 | if (i & __GFP_DMA) |
1456 | k = ZONE_DMA; |
1457 | |
1458 | j = build_zonelists_node(NODE_DATA(node), zonelist, j, k); |
1459 | zonelist->zones[j] = NULL; |
1460 | } |
1461 | } |
1462 | } |
1463 | |
1464 | #else /* CONFIG_NUMA */ |
1465 | |
1466 | static void __init build_zonelists(pg_data_t *pgdat) |
1467 | { |
1468 | int i, j, k, node, local_node; |
1469 | |
1470 | local_node = pgdat->node_id; |
1471 | for (i = 0; i < GFP_ZONETYPES; i++) { |
1472 | struct zonelist *zonelist; |
1473 | |
1474 | zonelist = pgdat->node_zonelists + i; |
1475 | |
1476 | j = 0; |
1477 | k = ZONE_NORMAL; |
1478 | if (i & __GFP_HIGHMEM) |
1479 | k = ZONE_HIGHMEM; |
1480 | if (i & __GFP_DMA) |
1481 | k = ZONE_DMA; |
1482 | |
1483 | j = build_zonelists_node(pgdat, zonelist, j, k); |
1484 | /* |
1485 | * Now we build the zonelist so that it contains the zones |
1486 | * of all the other nodes. |
1487 | * We don't want to pressure a particular node, so when |
1488 | * building the zones for node N, we make sure that the |
1489 | * zones coming right after the local ones are those from |
1490 | * node N+1 (modulo N) |
1491 | */ |
1492 | for (node = local_node + 1; node < MAX_NUMNODES; node++) { |
1493 | if (!node_online(node)) |
1494 | continue; |
1495 | j = build_zonelists_node(NODE_DATA(node), zonelist, j, k); |
1496 | } |
1497 | for (node = 0; node < local_node; node++) { |
1498 | if (!node_online(node)) |
1499 | continue; |
1500 | j = build_zonelists_node(NODE_DATA(node), zonelist, j, k); |
1501 | } |
1502 | |
1503 | zonelist->zones[j] = NULL; |
1504 | } |
1505 | } |
1506 | |
1507 | #endif /* CONFIG_NUMA */ |
1508 | |
1509 | void __init build_all_zonelists(void) |
1510 | { |
1511 | int i; |
1512 | |
1513 | for_each_online_node(i) |
1514 | build_zonelists(NODE_DATA(i)); |
1515 | printk("Built %i zonelists\n", num_online_nodes()); |
1516 | cpuset_init_current_mems_allowed(); |
1517 | } |
1518 | |
1519 | /* |
1520 | * Helper functions to size the waitqueue hash table. |
1521 | * Essentially these want to choose hash table sizes sufficiently |
1522 | * large so that collisions trying to wait on pages are rare. |
1523 | * But in fact, the number of active page waitqueues on typical |
1524 | * systems is ridiculously low, less than 200. So this is even |
1525 | * conservative, even though it seems large. |
1526 | * |
1527 | * The constant PAGES_PER_WAITQUEUE specifies the ratio of pages to |
1528 | * waitqueues, i.e. the size of the waitq table given the number of pages. |
1529 | */ |
1530 | #define PAGES_PER_WAITQUEUE 256 |
1531 | |
1532 | static inline unsigned long wait_table_size(unsigned long pages) |
1533 | { |
1534 | unsigned long size = 1; |
1535 | |
1536 | pages /= PAGES_PER_WAITQUEUE; |
1537 | |
1538 | while (size < pages) |
1539 | size <<= 1; |
1540 | |
1541 | /* |
1542 | * Once we have dozens or even hundreds of threads sleeping |
1543 | * on IO we've got bigger problems than wait queue collision. |
1544 | * Limit the size of the wait table to a reasonable size. |
1545 | */ |
1546 | size = min(size, 4096UL); |
1547 | |
1548 | return max(size, 4UL); |
1549 | } |
1550 | |
1551 | /* |
1552 | * This is an integer logarithm so that shifts can be used later |
1553 | * to extract the more random high bits from the multiplicative |
1554 | * hash function before the remainder is taken. |
1555 | */ |
1556 | static inline unsigned long wait_table_bits(unsigned long size) |
1557 | { |
1558 | return ffz(~size); |
1559 | } |
1560 | |
1561 | #define LONG_ALIGN(x) (((x)+(sizeof(long))-1)&~((sizeof(long))-1)) |
1562 | |
1563 | static void __init calculate_zone_totalpages(struct pglist_data *pgdat, |
1564 | unsigned long *zones_size, unsigned long *zholes_size) |
1565 | { |
1566 | unsigned long realtotalpages, totalpages = 0; |
1567 | int i; |
1568 | |
1569 | for (i = 0; i < MAX_NR_ZONES; i++) |
1570 | totalpages += zones_size[i]; |
1571 | pgdat->node_spanned_pages = totalpages; |
1572 | |
1573 | realtotalpages = totalpages; |
1574 | if (zholes_size) |
1575 | for (i = 0; i < MAX_NR_ZONES; i++) |
1576 | realtotalpages -= zholes_size[i]; |
1577 | pgdat->node_present_pages = realtotalpages; |
1578 | printk(KERN_DEBUG "On node %d totalpages: %lu\n", pgdat->node_id, realtotalpages); |
1579 | } |
1580 | |
1581 | |
1582 | /* |
1583 | * Initially all pages are reserved - free ones are freed |
1584 | * up by free_all_bootmem() once the early boot process is |
1585 | * done. Non-atomic initialization, single-pass. |
1586 | */ |
1587 | void __init memmap_init_zone(unsigned long size, int nid, unsigned long zone, |
1588 | unsigned long start_pfn) |
1589 | { |
1590 | struct page *start = pfn_to_page(start_pfn); |
1591 | struct page *page; |
1592 | |
1593 | for (page = start; page < (start + size); page++) { |
1594 | set_page_zone(page, NODEZONE(nid, zone)); |
1595 | set_page_count(page, 0); |
1596 | reset_page_mapcount(page); |
1597 | SetPageReserved(page); |
1598 | INIT_LIST_HEAD(&page->lru); |
1599 | #ifdef WANT_PAGE_VIRTUAL |
1600 | /* The shift won't overflow because ZONE_NORMAL is below 4G. */ |
1601 | if (!is_highmem_idx(zone)) |
1602 | set_page_address(page, __va(start_pfn << PAGE_SHIFT)); |
1603 | #endif |
1604 | start_pfn++; |
1605 | } |
1606 | } |
1607 | |
1608 | void zone_init_free_lists(struct pglist_data *pgdat, struct zone *zone, |
1609 | unsigned long size) |
1610 | { |
1611 | int order; |
1612 | for (order = 0; order < MAX_ORDER ; order++) { |
1613 | INIT_LIST_HEAD(&zone->free_area[order].free_list); |
1614 | zone->free_area[order].nr_free = 0; |
1615 | } |
1616 | } |
1617 | |
1618 | #ifndef __HAVE_ARCH_MEMMAP_INIT |
1619 | #define memmap_init(size, nid, zone, start_pfn) \ |
1620 | memmap_init_zone((size), (nid), (zone), (start_pfn)) |
1621 | #endif |
1622 | |
1623 | /* |
1624 | * Set up the zone data structures: |
1625 | * - mark all pages reserved |
1626 | * - mark all memory queues empty |
1627 | * - clear the memory bitmaps |
1628 | */ |
1629 | static void __init free_area_init_core(struct pglist_data *pgdat, |
1630 | unsigned long *zones_size, unsigned long *zholes_size) |
1631 | { |
1632 | unsigned long i, j; |
1633 | const unsigned long zone_required_alignment = 1UL << (MAX_ORDER-1); |
1634 | int cpu, nid = pgdat->node_id; |
1635 | unsigned long zone_start_pfn = pgdat->node_start_pfn; |
1636 | |
1637 | pgdat->nr_zones = 0; |
1638 | init_waitqueue_head(&pgdat->kswapd_wait); |
1639 | pgdat->kswapd_max_order = 0; |
1640 | |
1641 | for (j = 0; j < MAX_NR_ZONES; j++) { |
1642 | struct zone *zone = pgdat->node_zones + j; |
1643 | unsigned long size, realsize; |
1644 | unsigned long batch; |
1645 | |
1646 | zone_table[NODEZONE(nid, j)] = zone; |
1647 | realsize = size = zones_size[j]; |
1648 | if (zholes_size) |
1649 | realsize -= zholes_size[j]; |
1650 | |
1651 | if (j == ZONE_DMA || j == ZONE_NORMAL) |
1652 | nr_kernel_pages += realsize; |
1653 | nr_all_pages += realsize; |
1654 | |
1655 | zone->spanned_pages = size; |
1656 | zone->present_pages = realsize; |
1657 | zone->name = zone_names[j]; |
1658 | spin_lock_init(&zone->lock); |
1659 | spin_lock_init(&zone->lru_lock); |
1660 | zone->zone_pgdat = pgdat; |
1661 | zone->free_pages = 0; |
1662 | |
1663 | zone->temp_priority = zone->prev_priority = DEF_PRIORITY; |
1664 | |
1665 | /* |
1666 | * The per-cpu-pages pools are set to around 1000th of the |
1667 | * size of the zone. But no more than 1/4 of a meg - there's |
1668 | * no point in going beyond the size of L2 cache. |
1669 | * |
1670 | * OK, so we don't know how big the cache is. So guess. |
1671 | */ |
1672 | batch = zone->present_pages / 1024; |
1673 | if (batch * PAGE_SIZE > 256 * 1024) |
1674 | batch = (256 * 1024) / PAGE_SIZE; |
1675 | batch /= 4; /* We effectively *= 4 below */ |
1676 | if (batch < 1) |
1677 | batch = 1; |
1678 | |
1679 | /* |
1680 | * Clamp the batch to a 2^n - 1 value. Having a power |
1681 | * of 2 value was found to be more likely to have |
1682 | * suboptimal cache aliasing properties in some cases. |
1683 | * |
1684 | * For example if 2 tasks are alternately allocating |
1685 | * batches of pages, one task can end up with a lot |
1686 | * of pages of one half of the possible page colors |
1687 | * and the other with pages of the other colors. |
1688 | */ |
1689 | batch = (1 << fls(batch + batch/2)) - 1; |
1690 | |
1691 | for (cpu = 0; cpu < NR_CPUS; cpu++) { |
1692 | struct per_cpu_pages *pcp; |
1693 | |
1694 | pcp = &zone->pageset[cpu].pcp[0]; /* hot */ |
1695 | pcp->count = 0; |
1696 | pcp->low = 2 * batch; |
1697 | pcp->high = 6 * batch; |
1698 | pcp->batch = 1 * batch; |
1699 | INIT_LIST_HEAD(&pcp->list); |
1700 | |
1701 | pcp = &zone->pageset[cpu].pcp[1]; /* cold */ |
1702 | pcp->count = 0; |
1703 | pcp->low = 0; |
1704 | pcp->high = 2 * batch; |
1705 | pcp->batch = 1 * batch; |
1706 | INIT_LIST_HEAD(&pcp->list); |
1707 | } |
1708 | printk(KERN_DEBUG " %s zone: %lu pages, LIFO batch:%lu\n", |
1709 | zone_names[j], realsize, batch); |
1710 | INIT_LIST_HEAD(&zone->active_list); |
1711 | INIT_LIST_HEAD(&zone->inactive_list); |
1712 | zone->nr_scan_active = 0; |
1713 | zone->nr_scan_inactive = 0; |
1714 | zone->nr_active = 0; |
1715 | zone->nr_inactive = 0; |
1716 | if (!size) |
1717 | continue; |
1718 | |
1719 | /* |
1720 | * The per-page waitqueue mechanism uses hashed waitqueues |
1721 | * per zone. |
1722 | */ |
1723 | zone->wait_table_size = wait_table_size(size); |
1724 | zone->wait_table_bits = |
1725 | wait_table_bits(zone->wait_table_size); |
1726 | zone->wait_table = (wait_queue_head_t *) |
1727 | alloc_bootmem_node(pgdat, zone->wait_table_size |
1728 | * sizeof(wait_queue_head_t)); |
1729 | |
1730 | for(i = 0; i < zone->wait_table_size; ++i) |
1731 | init_waitqueue_head(zone->wait_table + i); |
1732 | |
1733 | pgdat->nr_zones = j+1; |
1734 | |
1735 | zone->zone_mem_map = pfn_to_page(zone_start_pfn); |
1736 | zone->zone_start_pfn = zone_start_pfn; |
1737 | |
1738 | if ((zone_start_pfn) & (zone_required_alignment-1)) |
1739 | printk(KERN_CRIT "BUG: wrong zone alignment, it will crash\n"); |
1740 | |
1741 | memmap_init(size, nid, j, zone_start_pfn); |
1742 | |
1743 | zone_start_pfn += size; |
1744 | |
1745 | zone_init_free_lists(pgdat, zone, zone->spanned_pages); |
1746 | } |
1747 | } |
1748 | |
1749 | static void __init alloc_node_mem_map(struct pglist_data *pgdat) |
1750 | { |
1751 | unsigned long size; |
1752 | |
1753 | /* Skip empty nodes */ |
1754 | if (!pgdat->node_spanned_pages) |
1755 | return; |
1756 | |
1757 | /* ia64 gets its own node_mem_map, before this, without bootmem */ |
1758 | if (!pgdat->node_mem_map) { |
1759 | size = (pgdat->node_spanned_pages + 1) * sizeof(struct page); |
1760 | pgdat->node_mem_map = alloc_bootmem_node(pgdat, size); |
1761 | } |
1762 | #ifndef CONFIG_DISCONTIGMEM |
1763 | /* |
1764 | * With no DISCONTIG, the global mem_map is just set as node 0's |
1765 | */ |
1766 | if (pgdat == NODE_DATA(0)) |
1767 | mem_map = NODE_DATA(0)->node_mem_map; |
1768 | #endif |
1769 | } |
1770 | |
1771 | void __init free_area_init_node(int nid, struct pglist_data *pgdat, |
1772 | unsigned long *zones_size, unsigned long node_start_pfn, |
1773 | unsigned long *zholes_size) |
1774 | { |
1775 | pgdat->node_id = nid; |
1776 | pgdat->node_start_pfn = node_start_pfn; |
1777 | calculate_zone_totalpages(pgdat, zones_size, zholes_size); |
1778 | |
1779 | alloc_node_mem_map(pgdat); |
1780 | |
1781 | free_area_init_core(pgdat, zones_size, zholes_size); |
1782 | } |
1783 | |
1784 | #ifndef CONFIG_DISCONTIGMEM |
1785 | static bootmem_data_t contig_bootmem_data; |
1786 | struct pglist_data contig_page_data = { .bdata = &contig_bootmem_data }; |
1787 | |
1788 | EXPORT_SYMBOL(contig_page_data); |
1789 | |
1790 | void __init free_area_init(unsigned long *zones_size) |
1791 | { |
1792 | free_area_init_node(0, &contig_page_data, zones_size, |
1793 | __pa(PAGE_OFFSET) >> PAGE_SHIFT, NULL); |
1794 | } |
1795 | #endif |
1796 | |
1797 | #ifdef CONFIG_PROC_FS |
1798 | |
1799 | #include <linux/seq_file.h> |
1800 | |
1801 | static void *frag_start(struct seq_file *m, loff_t *pos) |
1802 | { |
1803 | pg_data_t *pgdat; |
1804 | loff_t node = *pos; |
1805 | |
1806 | for (pgdat = pgdat_list; pgdat && node; pgdat = pgdat->pgdat_next) |
1807 | --node; |
1808 | |
1809 | return pgdat; |
1810 | } |
1811 | |
1812 | static void *frag_next(struct seq_file *m, void *arg, loff_t *pos) |
1813 | { |
1814 | pg_data_t *pgdat = (pg_data_t *)arg; |
1815 | |
1816 | (*pos)++; |
1817 | return pgdat->pgdat_next; |
1818 | } |
1819 | |
1820 | static void frag_stop(struct seq_file *m, void *arg) |
1821 | { |
1822 | } |
1823 | |
1824 | /* |
1825 | * This walks the free areas for each zone. |
1826 | */ |
1827 | static int frag_show(struct seq_file *m, void *arg) |
1828 | { |
1829 | pg_data_t *pgdat = (pg_data_t *)arg; |
1830 | struct zone *zone; |
1831 | struct zone *node_zones = pgdat->node_zones; |
1832 | unsigned long flags; |
1833 | int order; |
1834 | |
1835 | for (zone = node_zones; zone - node_zones < MAX_NR_ZONES; ++zone) { |
1836 | if (!zone->present_pages) |
1837 | continue; |
1838 | |
1839 | spin_lock_irqsave(&zone->lock, flags); |
1840 | seq_printf(m, "Node %d, zone %8s ", pgdat->node_id, zone->name); |
1841 | for (order = 0; order < MAX_ORDER; ++order) |
1842 | seq_printf(m, "%6lu ", zone->free_area[order].nr_free); |
1843 | spin_unlock_irqrestore(&zone->lock, flags); |
1844 | seq_putc(m, '\n'); |
1845 | } |
1846 | return 0; |
1847 | } |
1848 | |
1849 | struct seq_operations fragmentation_op = { |
1850 | .start = frag_start, |
1851 | .next = frag_next, |
1852 | .stop = frag_stop, |
1853 | .show = frag_show, |
1854 | }; |
1855 | |
1856 | static char *vmstat_text[] = { |
1857 | "nr_dirty", |
1858 | "nr_writeback", |
1859 | "nr_unstable", |
1860 | "nr_page_table_pages", |
1861 | "nr_mapped", |
1862 | "nr_slab", |
1863 | |
1864 | "pgpgin", |
1865 | "pgpgout", |
1866 | "pswpin", |
1867 | "pswpout", |
1868 | "pgalloc_high", |
1869 | |
1870 | "pgalloc_normal", |
1871 | "pgalloc_dma", |
1872 | "pgfree", |
1873 | "pgactivate", |
1874 | "pgdeactivate", |
1875 | |
1876 | "pgfault", |
1877 | "pgmajfault", |
1878 | "pgrefill_high", |
1879 | "pgrefill_normal", |
1880 | "pgrefill_dma", |
1881 | |
1882 | "pgsteal_high", |
1883 | "pgsteal_normal", |
1884 | "pgsteal_dma", |
1885 | "pgscan_kswapd_high", |
1886 | "pgscan_kswapd_normal", |
1887 | |
1888 | "pgscan_kswapd_dma", |
1889 | "pgscan_direct_high", |
1890 | "pgscan_direct_normal", |
1891 | "pgscan_direct_dma", |
1892 | "pginodesteal", |
1893 | |
1894 | "slabs_scanned", |
1895 | "kswapd_steal", |
1896 | "kswapd_inodesteal", |
1897 | "pageoutrun", |
1898 | "allocstall", |
1899 | |
1900 | "pgrotated", |
1901 | "nr_bounce", |
1902 | }; |
1903 | |
1904 | static void *vmstat_start(struct seq_file *m, loff_t *pos) |
1905 | { |
1906 | struct page_state *ps; |
1907 | |
1908 | if (*pos >= ARRAY_SIZE(vmstat_text)) |
1909 | return NULL; |
1910 | |
1911 | ps = kmalloc(sizeof(*ps), GFP_KERNEL); |
1912 | m->private = ps; |
1913 | if (!ps) |
1914 | return ERR_PTR(-ENOMEM); |
1915 | get_full_page_state(ps); |
1916 | ps->pgpgin /= 2; /* sectors -> kbytes */ |
1917 | ps->pgpgout /= 2; |
1918 | return (unsigned long *)ps + *pos; |
1919 | } |
1920 | |
1921 | static void *vmstat_next(struct seq_file *m, void *arg, loff_t *pos) |
1922 | { |
1923 | (*pos)++; |
1924 | if (*pos >= ARRAY_SIZE(vmstat_text)) |
1925 | return NULL; |
1926 | return (unsigned long *)m->private + *pos; |
1927 | } |
1928 | |
1929 | static int vmstat_show(struct seq_file *m, void *arg) |
1930 | { |
1931 | unsigned long *l = arg; |
1932 | unsigned long off = l - (unsigned long *)m->private; |
1933 | |
1934 | seq_printf(m, "%s %lu\n", vmstat_text[off], *l); |
1935 | return 0; |
1936 | } |
1937 | |
1938 | static void vmstat_stop(struct seq_file *m, void *arg) |
1939 | { |
1940 | kfree(m->private); |
1941 | m->private = NULL; |
1942 | } |
1943 | |
1944 | struct seq_operations vmstat_op = { |
1945 | .start = vmstat_start, |
1946 | .next = vmstat_next, |
1947 | .stop = vmstat_stop, |
1948 | .show = vmstat_show, |
1949 | }; |
1950 | |
1951 | #endif /* CONFIG_PROC_FS */ |
1952 | |
1953 | #ifdef CONFIG_HOTPLUG_CPU |
1954 | static int page_alloc_cpu_notify(struct notifier_block *self, |
1955 | unsigned long action, void *hcpu) |
1956 | { |
1957 | int cpu = (unsigned long)hcpu; |
1958 | long *count; |
1959 | unsigned long *src, *dest; |
1960 | |
1961 | if (action == CPU_DEAD) { |
1962 | int i; |
1963 | |
1964 | /* Drain local pagecache count. */ |
1965 | count = &per_cpu(nr_pagecache_local, cpu); |
1966 | atomic_add(*count, &nr_pagecache); |
1967 | *count = 0; |
1968 | local_irq_disable(); |
1969 | __drain_pages(cpu); |
1970 | |
1971 | /* Add dead cpu's page_states to our own. */ |
1972 | dest = (unsigned long *)&__get_cpu_var(page_states); |
1973 | src = (unsigned long *)&per_cpu(page_states, cpu); |
1974 | |
1975 | for (i = 0; i < sizeof(struct page_state)/sizeof(unsigned long); |
1976 | i++) { |
1977 | dest[i] += src[i]; |
1978 | src[i] = 0; |
1979 | } |
1980 | |
1981 | local_irq_enable(); |
1982 | } |
1983 | return NOTIFY_OK; |
1984 | } |
1985 | #endif /* CONFIG_HOTPLUG_CPU */ |
1986 | |
1987 | void __init page_alloc_init(void) |
1988 | { |
1989 | hotcpu_notifier(page_alloc_cpu_notify, 0); |
1990 | } |
1991 | |
1992 | /* |
1993 | * setup_per_zone_lowmem_reserve - called whenever |
1994 | * sysctl_lower_zone_reserve_ratio changes. Ensures that each zone |
1995 | * has a correct pages reserved value, so an adequate number of |
1996 | * pages are left in the zone after a successful __alloc_pages(). |
1997 | */ |
1998 | static void setup_per_zone_lowmem_reserve(void) |
1999 | { |
2000 | struct pglist_data *pgdat; |
2001 | int j, idx; |
2002 | |
2003 | for_each_pgdat(pgdat) { |
2004 | for (j = 0; j < MAX_NR_ZONES; j++) { |
2005 | struct zone *zone = pgdat->node_zones + j; |
2006 | unsigned long present_pages = zone->present_pages; |
2007 | |
2008 | zone->lowmem_reserve[j] = 0; |
2009 | |
2010 | for (idx = j-1; idx >= 0; idx--) { |
2011 | struct zone *lower_zone; |
2012 | |
2013 | if (sysctl_lowmem_reserve_ratio[idx] < 1) |
2014 | sysctl_lowmem_reserve_ratio[idx] = 1; |
2015 | |
2016 | lower_zone = pgdat->node_zones + idx; |
2017 | lower_zone->lowmem_reserve[j] = present_pages / |
2018 | sysctl_lowmem_reserve_ratio[idx]; |
2019 | present_pages += lower_zone->present_pages; |
2020 | } |
2021 | } |
2022 | } |
2023 | } |
2024 | |
2025 | /* |
2026 | * setup_per_zone_pages_min - called when min_free_kbytes changes. Ensures |
2027 | * that the pages_{min,low,high} values for each zone are set correctly |
2028 | * with respect to min_free_kbytes. |
2029 | */ |
2030 | static void setup_per_zone_pages_min(void) |
2031 | { |
2032 | unsigned long pages_min = min_free_kbytes >> (PAGE_SHIFT - 10); |
2033 | unsigned long lowmem_pages = 0; |
2034 | struct zone *zone; |
2035 | unsigned long flags; |
2036 | |
2037 | /* Calculate total number of !ZONE_HIGHMEM pages */ |
2038 | for_each_zone(zone) { |
2039 | if (!is_highmem(zone)) |
2040 | lowmem_pages += zone->present_pages; |
2041 | } |
2042 | |
2043 | for_each_zone(zone) { |
2044 | spin_lock_irqsave(&zone->lru_lock, flags); |
2045 | if (is_highmem(zone)) { |
2046 | /* |
2047 | * Often, highmem doesn't need to reserve any pages. |
2048 | * But the pages_min/low/high values are also used for |
2049 | * batching up page reclaim activity so we need a |
2050 | * decent value here. |
2051 | */ |
2052 | int min_pages; |
2053 | |
2054 | min_pages = zone->present_pages / 1024; |
2055 | if (min_pages < SWAP_CLUSTER_MAX) |
2056 | min_pages = SWAP_CLUSTER_MAX; |
2057 | if (min_pages > 128) |
2058 | min_pages = 128; |
2059 | zone->pages_min = min_pages; |
2060 | } else { |
2061 | /* if it's a lowmem zone, reserve a number of pages |
2062 | * proportionate to the zone's size. |
2063 | */ |
2064 | zone->pages_min = (pages_min * zone->present_pages) / |
2065 | lowmem_pages; |
2066 | } |
2067 | |
2068 | /* |
2069 | * When interpreting these watermarks, just keep in mind that: |
2070 | * zone->pages_min == (zone->pages_min * 4) / 4; |
2071 | */ |
2072 | zone->pages_low = (zone->pages_min * 5) / 4; |
2073 | zone->pages_high = (zone->pages_min * 6) / 4; |
2074 | spin_unlock_irqrestore(&zone->lru_lock, flags); |
2075 | } |
2076 | } |
2077 | |
2078 | /* |
2079 | * Initialise min_free_kbytes. |
2080 | * |
2081 | * For small machines we want it small (128k min). For large machines |
2082 | * we want it large (64MB max). But it is not linear, because network |
2083 | * bandwidth does not increase linearly with machine size. We use |
2084 | * |
2085 | * min_free_kbytes = 4 * sqrt(lowmem_kbytes), for better accuracy: |
2086 | * min_free_kbytes = sqrt(lowmem_kbytes * 16) |
2087 | * |
2088 | * which yields |
2089 | * |
2090 | * 16MB: 512k |
2091 | * 32MB: 724k |
2092 | * 64MB: 1024k |
2093 | * 128MB: 1448k |
2094 | * 256MB: 2048k |
2095 | * 512MB: 2896k |
2096 | * 1024MB: 4096k |
2097 | * 2048MB: 5792k |
2098 | * 4096MB: 8192k |
2099 | * 8192MB: 11584k |
2100 | * 16384MB: 16384k |
2101 | */ |
2102 | static int __init init_per_zone_pages_min(void) |
2103 | { |
2104 | unsigned long lowmem_kbytes; |
2105 | |
2106 | lowmem_kbytes = nr_free_buffer_pages() * (PAGE_SIZE >> 10); |
2107 | |
2108 | min_free_kbytes = int_sqrt(lowmem_kbytes * 16); |
2109 | if (min_free_kbytes < 128) |
2110 | min_free_kbytes = 128; |
2111 | if (min_free_kbytes > 65536) |
2112 | min_free_kbytes = 65536; |
2113 | setup_per_zone_pages_min(); |
2114 | setup_per_zone_lowmem_reserve(); |
2115 | return 0; |
2116 | } |
2117 | module_init(init_per_zone_pages_min) |
2118 | |
2119 | /* |
2120 | * min_free_kbytes_sysctl_handler - just a wrapper around proc_dointvec() so |
2121 | * that we can call two helper functions whenever min_free_kbytes |
2122 | * changes. |
2123 | */ |
2124 | int min_free_kbytes_sysctl_handler(ctl_table *table, int write, |
2125 | struct file *file, void __user *buffer, size_t *length, loff_t *ppos) |
2126 | { |
2127 | proc_dointvec(table, write, file, buffer, length, ppos); |
2128 | setup_per_zone_pages_min(); |
2129 | return 0; |
2130 | } |
2131 | |
2132 | /* |
2133 | * lowmem_reserve_ratio_sysctl_handler - just a wrapper around |
2134 | * proc_dointvec() so that we can call setup_per_zone_lowmem_reserve() |
2135 | * whenever sysctl_lowmem_reserve_ratio changes. |
2136 | * |
2137 | * The reserve ratio obviously has absolutely no relation with the |
2138 | * pages_min watermarks. The lowmem reserve ratio can only make sense |
2139 | * if in function of the boot time zone sizes. |
2140 | */ |
2141 | int lowmem_reserve_ratio_sysctl_handler(ctl_table *table, int write, |
2142 | struct file *file, void __user *buffer, size_t *length, loff_t *ppos) |
2143 | { |
2144 | proc_dointvec_minmax(table, write, file, buffer, length, ppos); |
2145 | setup_per_zone_lowmem_reserve(); |
2146 | return 0; |
2147 | } |
2148 | |
2149 | __initdata int hashdist = HASHDIST_DEFAULT; |
2150 | |
2151 | #ifdef CONFIG_NUMA |
2152 | static int __init set_hashdist(char *str) |
2153 | { |
2154 | if (!str) |
2155 | return 0; |
2156 | hashdist = simple_strtoul(str, &str, 0); |
2157 | return 1; |
2158 | } |
2159 | __setup("hashdist=", set_hashdist); |
2160 | #endif |
2161 | |
2162 | /* |
2163 | * allocate a large system hash table from bootmem |
2164 | * - it is assumed that the hash table must contain an exact power-of-2 |
2165 | * quantity of entries |
2166 | * - limit is the number of hash buckets, not the total allocation size |
2167 | */ |
2168 | void *__init alloc_large_system_hash(const char *tablename, |
2169 | unsigned long bucketsize, |
2170 | unsigned long numentries, |
2171 | int scale, |
2172 | int flags, |
2173 | unsigned int *_hash_shift, |
2174 | unsigned int *_hash_mask, |
2175 | unsigned long limit) |
2176 | { |
2177 | unsigned long long max = limit; |
2178 | unsigned long log2qty, size; |
2179 | void *table = NULL; |
2180 | |
2181 | /* allow the kernel cmdline to have a say */ |
2182 | if (!numentries) { |
2183 | /* round applicable memory size up to nearest megabyte */ |
2184 | numentries = (flags & HASH_HIGHMEM) ? nr_all_pages : nr_kernel_pages; |
2185 | numentries += (1UL << (20 - PAGE_SHIFT)) - 1; |
2186 | numentries >>= 20 - PAGE_SHIFT; |
2187 | numentries <<= 20 - PAGE_SHIFT; |
2188 | |
2189 | /* limit to 1 bucket per 2^scale bytes of low memory */ |
2190 | if (scale > PAGE_SHIFT) |
2191 | numentries >>= (scale - PAGE_SHIFT); |
2192 | else |
2193 | numentries <<= (PAGE_SHIFT - scale); |
2194 | } |
2195 | /* rounded up to nearest power of 2 in size */ |
2196 | numentries = 1UL << (long_log2(numentries) + 1); |
2197 | |
2198 | /* limit allocation size to 1/16 total memory by default */ |
2199 | if (max == 0) { |
2200 | max = ((unsigned long long)nr_all_pages << PAGE_SHIFT) >> 4; |
2201 | do_div(max, bucketsize); |
2202 | } |
2203 | |
2204 | if (numentries > max) |
2205 | numentries = max; |
2206 | |
2207 | log2qty = long_log2(numentries); |
2208 | |
2209 | do { |
2210 | size = bucketsize << log2qty; |
2211 | if (flags & HASH_EARLY) |
2212 | table = alloc_bootmem(size); |
2213 | else if (hashdist) |
2214 | table = __vmalloc(size, GFP_ATOMIC, PAGE_KERNEL); |
2215 | else { |
2216 | unsigned long order; |
2217 | for (order = 0; ((1UL << order) << PAGE_SHIFT) < size; order++) |
2218 | ; |
2219 | table = (void*) __get_free_pages(GFP_ATOMIC, order); |
2220 | } |
2221 | } while (!table && size > PAGE_SIZE && --log2qty); |
2222 | |
2223 | if (!table) |
2224 | panic("Failed to allocate %s hash table\n", tablename); |
2225 | |
2226 | printk("%s hash table entries: %d (order: %d, %lu bytes)\n", |
2227 | tablename, |
2228 | (1U << log2qty), |
2229 | long_log2(size) - PAGE_SHIFT, |
2230 | size); |
2231 | |
2232 | if (_hash_shift) |
2233 | *_hash_shift = log2qty; |
2234 | if (_hash_mask) |
2235 | *_hash_mask = (1 << log2qty) - 1; |
2236 | |
2237 | return table; |
2238 | } |