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16#include <linux/mm.h>
17#include <linux/sched.h>
18#include <linux/kernel_stat.h>
19#include <linux/swap.h>
20#include <linux/mman.h>
21#include <linux/pagemap.h>
22#include <linux/pagevec.h>
23#include <linux/init.h>
24#include <linux/module.h>
25#include <linux/mm_inline.h>
26#include <linux/buffer_head.h>
27#include <linux/percpu_counter.h>
28#include <linux/percpu.h>
29#include <linux/cpu.h>
30#include <linux/notifier.h>
31#include <linux/backing-dev.h>
32
33
34int page_cluster;
35
36static DEFINE_PER_CPU(struct pagevec, lru_add_pvecs) = { 0, };
37static DEFINE_PER_CPU(struct pagevec, lru_add_active_pvecs) = { 0, };
38static DEFINE_PER_CPU(struct pagevec, lru_rotate_pvecs) = { 0, };
39
40
41
42
43
44static void fastcall __page_cache_release(struct page *page)
45{
46 if (PageLRU(page)) {
47 unsigned long flags;
48 struct zone *zone = page_zone(page);
49
50 spin_lock_irqsave(&zone->lru_lock, flags);
51 VM_BUG_ON(!PageLRU(page));
52 __ClearPageLRU(page);
53 del_page_from_lru(zone, page);
54 spin_unlock_irqrestore(&zone->lru_lock, flags);
55 }
56 free_hot_page(page);
57}
58
59static void put_compound_page(struct page *page)
60{
61 page = compound_head(page);
62 if (put_page_testzero(page)) {
63 compound_page_dtor *dtor;
64
65 dtor = get_compound_page_dtor(page);
66 (*dtor)(page);
67 }
68}
69
70void put_page(struct page *page)
71{
72 if (unlikely(PageCompound(page)))
73 put_compound_page(page);
74 else if (put_page_testzero(page))
75 __page_cache_release(page);
76}
77EXPORT_SYMBOL(put_page);
78
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86
87void put_pages_list(struct list_head *pages)
88{
89 while (!list_empty(pages)) {
90 struct page *victim;
91
92 victim = list_entry(pages->prev, struct page, lru);
93 list_del(&victim->lru);
94 page_cache_release(victim);
95 }
96}
97EXPORT_SYMBOL(put_pages_list);
98
99
100
101
102
103static void pagevec_move_tail(struct pagevec *pvec)
104{
105 int i;
106 int pgmoved = 0;
107 struct zone *zone = NULL;
108
109 for (i = 0; i < pagevec_count(pvec); i++) {
110 struct page *page = pvec->pages[i];
111 struct zone *pagezone = page_zone(page);
112
113 if (pagezone != zone) {
114 if (zone)
115 spin_unlock(&zone->lru_lock);
116 zone = pagezone;
117 spin_lock(&zone->lru_lock);
118 }
119 if (PageLRU(page) && !PageActive(page)) {
120 list_move_tail(&page->lru, &zone->inactive_list);
121 pgmoved++;
122 }
123 }
124 if (zone)
125 spin_unlock(&zone->lru_lock);
126 __count_vm_events(PGROTATED, pgmoved);
127 release_pages(pvec->pages, pvec->nr, pvec->cold);
128 pagevec_reinit(pvec);
129}
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136
137
138int rotate_reclaimable_page(struct page *page)
139{
140 struct pagevec *pvec;
141 unsigned long flags;
142
143 if (PageLocked(page))
144 return 1;
145 if (PageDirty(page))
146 return 1;
147 if (PageActive(page))
148 return 1;
149 if (!PageLRU(page))
150 return 1;
151
152 page_cache_get(page);
153 local_irq_save(flags);
154 pvec = &__get_cpu_var(lru_rotate_pvecs);
155 if (!pagevec_add(pvec, page))
156 pagevec_move_tail(pvec);
157 local_irq_restore(flags);
158
159 if (!test_clear_page_writeback(page))
160 BUG();
161
162 return 0;
163}
164
165
166
167
168void fastcall activate_page(struct page *page)
169{
170 struct zone *zone = page_zone(page);
171
172 spin_lock_irq(&zone->lru_lock);
173 if (PageLRU(page) && !PageActive(page)) {
174 del_page_from_inactive_list(zone, page);
175 SetPageActive(page);
176 add_page_to_active_list(zone, page);
177 __count_vm_event(PGACTIVATE);
178 }
179 spin_unlock_irq(&zone->lru_lock);
180}
181
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188
189void fastcall mark_page_accessed(struct page *page)
190{
191 if (!PageActive(page) && PageReferenced(page) && PageLRU(page)) {
192 activate_page(page);
193 ClearPageReferenced(page);
194 } else if (!PageReferenced(page)) {
195 SetPageReferenced(page);
196 }
197}
198
199EXPORT_SYMBOL(mark_page_accessed);
200
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203
204
205void fastcall lru_cache_add(struct page *page)
206{
207 struct pagevec *pvec = &get_cpu_var(lru_add_pvecs);
208
209 page_cache_get(page);
210 if (!pagevec_add(pvec, page))
211 __pagevec_lru_add(pvec);
212 put_cpu_var(lru_add_pvecs);
213}
214
215void fastcall lru_cache_add_active(struct page *page)
216{
217 struct pagevec *pvec = &get_cpu_var(lru_add_active_pvecs);
218
219 page_cache_get(page);
220 if (!pagevec_add(pvec, page))
221 __pagevec_lru_add_active(pvec);
222 put_cpu_var(lru_add_active_pvecs);
223}
224
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228
229
230static void drain_cpu_pagevecs(int cpu)
231{
232 struct pagevec *pvec;
233
234 pvec = &per_cpu(lru_add_pvecs, cpu);
235 if (pagevec_count(pvec))
236 __pagevec_lru_add(pvec);
237
238 pvec = &per_cpu(lru_add_active_pvecs, cpu);
239 if (pagevec_count(pvec))
240 __pagevec_lru_add_active(pvec);
241
242 pvec = &per_cpu(lru_rotate_pvecs, cpu);
243 if (pagevec_count(pvec)) {
244 unsigned long flags;
245
246
247 local_irq_save(flags);
248 pagevec_move_tail(pvec);
249 local_irq_restore(flags);
250 }
251}
252
253void lru_add_drain(void)
254{
255 drain_cpu_pagevecs(get_cpu());
256 put_cpu();
257}
258
259#ifdef CONFIG_NUMA
260static void lru_add_drain_per_cpu(struct work_struct *dummy)
261{
262 lru_add_drain();
263}
264
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268int lru_add_drain_all(void)
269{
270 return schedule_on_each_cpu(lru_add_drain_per_cpu);
271}
272
273#else
274
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277
278int lru_add_drain_all(void)
279{
280 lru_add_drain();
281 return 0;
282}
283#endif
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296
297void release_pages(struct page **pages, int nr, int cold)
298{
299 int i;
300 struct pagevec pages_to_free;
301 struct zone *zone = NULL;
302 unsigned long uninitialized_var(flags);
303
304 pagevec_init(&pages_to_free, cold);
305 for (i = 0; i < nr; i++) {
306 struct page *page = pages[i];
307
308 if (unlikely(PageCompound(page))) {
309 if (zone) {
310 spin_unlock_irqrestore(&zone->lru_lock, flags);
311 zone = NULL;
312 }
313 put_compound_page(page);
314 continue;
315 }
316
317 if (!put_page_testzero(page))
318 continue;
319
320 if (PageLRU(page)) {
321 struct zone *pagezone = page_zone(page);
322 if (pagezone != zone) {
323 if (zone)
324 spin_unlock_irqrestore(&zone->lru_lock,
325 flags);
326 zone = pagezone;
327 spin_lock_irqsave(&zone->lru_lock, flags);
328 }
329 VM_BUG_ON(!PageLRU(page));
330 __ClearPageLRU(page);
331 del_page_from_lru(zone, page);
332 }
333
334 if (!pagevec_add(&pages_to_free, page)) {
335 if (zone) {
336 spin_unlock_irqrestore(&zone->lru_lock, flags);
337 zone = NULL;
338 }
339 __pagevec_free(&pages_to_free);
340 pagevec_reinit(&pages_to_free);
341 }
342 }
343 if (zone)
344 spin_unlock_irqrestore(&zone->lru_lock, flags);
345
346 pagevec_free(&pages_to_free);
347}
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358
359void __pagevec_release(struct pagevec *pvec)
360{
361 lru_add_drain();
362 release_pages(pvec->pages, pagevec_count(pvec), pvec->cold);
363 pagevec_reinit(pvec);
364}
365
366EXPORT_SYMBOL(__pagevec_release);
367
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372
373void __pagevec_release_nonlru(struct pagevec *pvec)
374{
375 int i;
376 struct pagevec pages_to_free;
377
378 pagevec_init(&pages_to_free, pvec->cold);
379 for (i = 0; i < pagevec_count(pvec); i++) {
380 struct page *page = pvec->pages[i];
381
382 VM_BUG_ON(PageLRU(page));
383 if (put_page_testzero(page))
384 pagevec_add(&pages_to_free, page);
385 }
386 pagevec_free(&pages_to_free);
387 pagevec_reinit(pvec);
388}
389
390
391
392
393
394void __pagevec_lru_add(struct pagevec *pvec)
395{
396 int i;
397 struct zone *zone = NULL;
398
399 for (i = 0; i < pagevec_count(pvec); i++) {
400 struct page *page = pvec->pages[i];
401 struct zone *pagezone = page_zone(page);
402
403 if (pagezone != zone) {
404 if (zone)
405 spin_unlock_irq(&zone->lru_lock);
406 zone = pagezone;
407 spin_lock_irq(&zone->lru_lock);
408 }
409 VM_BUG_ON(PageLRU(page));
410 SetPageLRU(page);
411 add_page_to_inactive_list(zone, page);
412 }
413 if (zone)
414 spin_unlock_irq(&zone->lru_lock);
415 release_pages(pvec->pages, pvec->nr, pvec->cold);
416 pagevec_reinit(pvec);
417}
418
419EXPORT_SYMBOL(__pagevec_lru_add);
420
421void __pagevec_lru_add_active(struct pagevec *pvec)
422{
423 int i;
424 struct zone *zone = NULL;
425
426 for (i = 0; i < pagevec_count(pvec); i++) {
427 struct page *page = pvec->pages[i];
428 struct zone *pagezone = page_zone(page);
429
430 if (pagezone != zone) {
431 if (zone)
432 spin_unlock_irq(&zone->lru_lock);
433 zone = pagezone;
434 spin_lock_irq(&zone->lru_lock);
435 }
436 VM_BUG_ON(PageLRU(page));
437 SetPageLRU(page);
438 VM_BUG_ON(PageActive(page));
439 SetPageActive(page);
440 add_page_to_active_list(zone, page);
441 }
442 if (zone)
443 spin_unlock_irq(&zone->lru_lock);
444 release_pages(pvec->pages, pvec->nr, pvec->cold);
445 pagevec_reinit(pvec);
446}
447
448
449
450
451void pagevec_strip(struct pagevec *pvec)
452{
453 int i;
454
455 for (i = 0; i < pagevec_count(pvec); i++) {
456 struct page *page = pvec->pages[i];
457
458 if (PagePrivate(page) && !TestSetPageLocked(page)) {
459 if (PagePrivate(page))
460 try_to_release_page(page, 0);
461 unlock_page(page);
462 }
463 }
464}
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482unsigned pagevec_lookup(struct pagevec *pvec, struct address_space *mapping,
483 pgoff_t start, unsigned nr_pages)
484{
485 pvec->nr = find_get_pages(mapping, start, nr_pages, pvec->pages);
486 return pagevec_count(pvec);
487}
488
489EXPORT_SYMBOL(pagevec_lookup);
490
491unsigned pagevec_lookup_tag(struct pagevec *pvec, struct address_space *mapping,
492 pgoff_t *index, int tag, unsigned nr_pages)
493{
494 pvec->nr = find_get_pages_tag(mapping, index, tag,
495 nr_pages, pvec->pages);
496 return pagevec_count(pvec);
497}
498
499EXPORT_SYMBOL(pagevec_lookup_tag);
500
501#ifdef CONFIG_SMP
502
503
504
505
506#define ACCT_THRESHOLD max(16, NR_CPUS * 2)
507
508static DEFINE_PER_CPU(long, committed_space) = 0;
509
510void vm_acct_memory(long pages)
511{
512 long *local;
513
514 preempt_disable();
515 local = &__get_cpu_var(committed_space);
516 *local += pages;
517 if (*local > ACCT_THRESHOLD || *local < -ACCT_THRESHOLD) {
518 atomic_add(*local, &vm_committed_space);
519 *local = 0;
520 }
521 preempt_enable();
522}
523
524#ifdef CONFIG_HOTPLUG_CPU
525
526
527static int cpu_swap_callback(struct notifier_block *nfb,
528 unsigned long action,
529 void *hcpu)
530{
531 long *committed;
532
533 committed = &per_cpu(committed_space, (long)hcpu);
534 if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) {
535 atomic_add(*committed, &vm_committed_space);
536 *committed = 0;
537 drain_cpu_pagevecs((long)hcpu);
538 }
539 return NOTIFY_OK;
540}
541#endif
542#endif
543
544
545
546
547void __init swap_setup(void)
548{
549 unsigned long megs = num_physpages >> (20 - PAGE_SHIFT);
550
551#ifdef CONFIG_SWAP
552 bdi_init(swapper_space.backing_dev_info);
553#endif
554
555
556 if (megs < 16)
557 page_cluster = 2;
558 else
559 page_cluster = 3;
560
561
562
563
564#ifdef CONFIG_HOTPLUG_CPU
565 hotcpu_notifier(cpu_swap_callback, 0);
566#endif
567}
568