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-rw-r--r--mm/vmstat.c614
1 files changed, 614 insertions, 0 deletions
diff --git a/mm/vmstat.c b/mm/vmstat.c
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1/*
2 * linux/mm/vmstat.c
3 *
4 * Manages VM statistics
5 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
6 *
7 * zoned VM statistics
8 * Copyright (C) 2006 Silicon Graphics, Inc.,
9 * Christoph Lameter <christoph@lameter.com>
10 */
11
12#include <linux/config.h>
13#include <linux/mm.h>
14#include <linux/module.h>
15
16void __get_zone_counts(unsigned long *active, unsigned long *inactive,
17 unsigned long *free, struct pglist_data *pgdat)
18{
19 struct zone *zones = pgdat->node_zones;
20 int i;
21
22 *active = 0;
23 *inactive = 0;
24 *free = 0;
25 for (i = 0; i < MAX_NR_ZONES; i++) {
26 *active += zones[i].nr_active;
27 *inactive += zones[i].nr_inactive;
28 *free += zones[i].free_pages;
29 }
30}
31
32void get_zone_counts(unsigned long *active,
33 unsigned long *inactive, unsigned long *free)
34{
35 struct pglist_data *pgdat;
36
37 *active = 0;
38 *inactive = 0;
39 *free = 0;
40 for_each_online_pgdat(pgdat) {
41 unsigned long l, m, n;
42 __get_zone_counts(&l, &m, &n, pgdat);
43 *active += l;
44 *inactive += m;
45 *free += n;
46 }
47}
48
49#ifdef CONFIG_VM_EVENT_COUNTERS
50DEFINE_PER_CPU(struct vm_event_state, vm_event_states) = {{0}};
51EXPORT_PER_CPU_SYMBOL(vm_event_states);
52
53static void sum_vm_events(unsigned long *ret, cpumask_t *cpumask)
54{
55 int cpu = 0;
56 int i;
57
58 memset(ret, 0, NR_VM_EVENT_ITEMS * sizeof(unsigned long));
59
60 cpu = first_cpu(*cpumask);
61 while (cpu < NR_CPUS) {
62 struct vm_event_state *this = &per_cpu(vm_event_states, cpu);
63
64 cpu = next_cpu(cpu, *cpumask);
65
66 if (cpu < NR_CPUS)
67 prefetch(&per_cpu(vm_event_states, cpu));
68
69
70 for (i = 0; i < NR_VM_EVENT_ITEMS; i++)
71 ret[i] += this->event[i];
72 }
73}
74
75/*
76 * Accumulate the vm event counters across all CPUs.
77 * The result is unavoidably approximate - it can change
78 * during and after execution of this function.
79*/
80void all_vm_events(unsigned long *ret)
81{
82 sum_vm_events(ret, &cpu_online_map);
83}
84
85#ifdef CONFIG_HOTPLUG
86/*
87 * Fold the foreign cpu events into our own.
88 *
89 * This is adding to the events on one processor
90 * but keeps the global counts constant.
91 */
92void vm_events_fold_cpu(int cpu)
93{
94 struct vm_event_state *fold_state = &per_cpu(vm_event_states, cpu);
95 int i;
96
97 for (i = 0; i < NR_VM_EVENT_ITEMS; i++) {
98 count_vm_events(i, fold_state->event[i]);
99 fold_state->event[i] = 0;
100 }
101}
102#endif /* CONFIG_HOTPLUG */
103
104#endif /* CONFIG_VM_EVENT_COUNTERS */
105
106/*
107 * Manage combined zone based / global counters
108 *
109 * vm_stat contains the global counters
110 */
111atomic_long_t vm_stat[NR_VM_ZONE_STAT_ITEMS];
112EXPORT_SYMBOL(vm_stat);
113
114#ifdef CONFIG_SMP
115
116#define STAT_THRESHOLD 32
117
118/*
119 * Determine pointer to currently valid differential byte given a zone and
120 * the item number.
121 *
122 * Preemption must be off
123 */
124static inline s8 *diff_pointer(struct zone *zone, enum zone_stat_item item)
125{
126 return &zone_pcp(zone, smp_processor_id())->vm_stat_diff[item];
127}
128
129/*
130 * For use when we know that interrupts are disabled.
131 */
132void __mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
133 int delta)
134{
135 s8 *p;
136 long x;
137
138 p = diff_pointer(zone, item);
139 x = delta + *p;
140
141 if (unlikely(x > STAT_THRESHOLD || x < -STAT_THRESHOLD)) {
142 zone_page_state_add(x, zone, item);
143 x = 0;
144 }
145
146 *p = x;
147}
148EXPORT_SYMBOL(__mod_zone_page_state);
149
150/*
151 * For an unknown interrupt state
152 */
153void mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
154 int delta)
155{
156 unsigned long flags;
157
158 local_irq_save(flags);
159 __mod_zone_page_state(zone, item, delta);
160 local_irq_restore(flags);
161}
162EXPORT_SYMBOL(mod_zone_page_state);
163
164/*
165 * Optimized increment and decrement functions.
166 *
167 * These are only for a single page and therefore can take a struct page *
168 * argument instead of struct zone *. This allows the inclusion of the code
169 * generated for page_zone(page) into the optimized functions.
170 *
171 * No overflow check is necessary and therefore the differential can be
172 * incremented or decremented in place which may allow the compilers to
173 * generate better code.
174 *
175 * The increment or decrement is known and therefore one boundary check can
176 * be omitted.
177 *
178 * Some processors have inc/dec instructions that are atomic vs an interrupt.
179 * However, the code must first determine the differential location in a zone
180 * based on the processor number and then inc/dec the counter. There is no
181 * guarantee without disabling preemption that the processor will not change
182 * in between and therefore the atomicity vs. interrupt cannot be exploited
183 * in a useful way here.
184 */
185static void __inc_zone_state(struct zone *zone, enum zone_stat_item item)
186{
187 s8 *p = diff_pointer(zone, item);
188
189 (*p)++;
190
191 if (unlikely(*p > STAT_THRESHOLD)) {
192 zone_page_state_add(*p, zone, item);
193 *p = 0;
194 }
195}
196
197void __inc_zone_page_state(struct page *page, enum zone_stat_item item)
198{
199 __inc_zone_state(page_zone(page), item);
200}
201EXPORT_SYMBOL(__inc_zone_page_state);
202
203void __dec_zone_page_state(struct page *page, enum zone_stat_item item)
204{
205 struct zone *zone = page_zone(page);
206 s8 *p = diff_pointer(zone, item);
207
208 (*p)--;
209
210 if (unlikely(*p < -STAT_THRESHOLD)) {
211 zone_page_state_add(*p, zone, item);
212 *p = 0;
213 }
214}
215EXPORT_SYMBOL(__dec_zone_page_state);
216
217void inc_zone_state(struct zone *zone, enum zone_stat_item item)
218{
219 unsigned long flags;
220
221 local_irq_save(flags);
222 __inc_zone_state(zone, item);
223 local_irq_restore(flags);
224}
225
226void inc_zone_page_state(struct page *page, enum zone_stat_item item)
227{
228 unsigned long flags;
229 struct zone *zone;
230
231 zone = page_zone(page);
232 local_irq_save(flags);
233 __inc_zone_state(zone, item);
234 local_irq_restore(flags);
235}
236EXPORT_SYMBOL(inc_zone_page_state);
237
238void dec_zone_page_state(struct page *page, enum zone_stat_item item)
239{
240 unsigned long flags;
241 struct zone *zone;
242 s8 *p;
243
244 zone = page_zone(page);
245 local_irq_save(flags);
246 p = diff_pointer(zone, item);
247
248 (*p)--;
249
250 if (unlikely(*p < -STAT_THRESHOLD)) {
251 zone_page_state_add(*p, zone, item);
252 *p = 0;
253 }
254 local_irq_restore(flags);
255}
256EXPORT_SYMBOL(dec_zone_page_state);
257
258/*
259 * Update the zone counters for one cpu.
260 */
261void refresh_cpu_vm_stats(int cpu)
262{
263 struct zone *zone;
264 int i;
265 unsigned long flags;
266
267 for_each_zone(zone) {
268 struct per_cpu_pageset *pcp;
269
270 pcp = zone_pcp(zone, cpu);
271
272 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
273 if (pcp->vm_stat_diff[i]) {
274 local_irq_save(flags);
275 zone_page_state_add(pcp->vm_stat_diff[i],
276 zone, i);
277 pcp->vm_stat_diff[i] = 0;
278 local_irq_restore(flags);
279 }
280 }
281}
282
283static void __refresh_cpu_vm_stats(void *dummy)
284{
285 refresh_cpu_vm_stats(smp_processor_id());
286}
287
288/*
289 * Consolidate all counters.
290 *
291 * Note that the result is less inaccurate but still inaccurate
292 * if concurrent processes are allowed to run.
293 */
294void refresh_vm_stats(void)
295{
296 on_each_cpu(__refresh_cpu_vm_stats, NULL, 0, 1);
297}
298EXPORT_SYMBOL(refresh_vm_stats);
299
300#endif
301
302#ifdef CONFIG_NUMA
303/*
304 * zonelist = the list of zones passed to the allocator
305 * z = the zone from which the allocation occurred.
306 *
307 * Must be called with interrupts disabled.
308 */
309void zone_statistics(struct zonelist *zonelist, struct zone *z)
310{
311 if (z->zone_pgdat == zonelist->zones[0]->zone_pgdat) {
312 __inc_zone_state(z, NUMA_HIT);
313 } else {
314 __inc_zone_state(z, NUMA_MISS);
315 __inc_zone_state(zonelist->zones[0], NUMA_FOREIGN);
316 }
317 if (z->zone_pgdat == NODE_DATA(numa_node_id()))
318 __inc_zone_state(z, NUMA_LOCAL);
319 else
320 __inc_zone_state(z, NUMA_OTHER);
321}
322#endif
323
324#ifdef CONFIG_PROC_FS
325
326#include <linux/seq_file.h>
327
328static void *frag_start(struct seq_file *m, loff_t *pos)
329{
330 pg_data_t *pgdat;
331 loff_t node = *pos;
332 for (pgdat = first_online_pgdat();
333 pgdat && node;
334 pgdat = next_online_pgdat(pgdat))
335 --node;
336
337 return pgdat;
338}
339
340static void *frag_next(struct seq_file *m, void *arg, loff_t *pos)
341{
342 pg_data_t *pgdat = (pg_data_t *)arg;
343
344 (*pos)++;
345 return next_online_pgdat(pgdat);
346}
347
348static void frag_stop(struct seq_file *m, void *arg)
349{
350}
351
352/*
353 * This walks the free areas for each zone.
354 */
355static int frag_show(struct seq_file *m, void *arg)
356{
357 pg_data_t *pgdat = (pg_data_t *)arg;
358 struct zone *zone;
359 struct zone *node_zones = pgdat->node_zones;
360 unsigned long flags;
361 int order;
362
363 for (zone = node_zones; zone - node_zones < MAX_NR_ZONES; ++zone) {
364 if (!populated_zone(zone))
365 continue;
366
367 spin_lock_irqsave(&zone->lock, flags);
368 seq_printf(m, "Node %d, zone %8s ", pgdat->node_id, zone->name);
369 for (order = 0; order < MAX_ORDER; ++order)
370 seq_printf(m, "%6lu ", zone->free_area[order].nr_free);
371 spin_unlock_irqrestore(&zone->lock, flags);
372 seq_putc(m, '\n');
373 }
374 return 0;
375}
376
377struct seq_operations fragmentation_op = {
378 .start = frag_start,
379 .next = frag_next,
380 .stop = frag_stop,
381 .show = frag_show,
382};
383
384static char *vmstat_text[] = {
385 /* Zoned VM counters */
386 "nr_anon_pages",
387 "nr_mapped",
388 "nr_file_pages",
389 "nr_slab",
390 "nr_page_table_pages",
391 "nr_dirty",
392 "nr_writeback",
393 "nr_unstable",
394 "nr_bounce",
395
396#ifdef CONFIG_NUMA
397 "numa_hit",
398 "numa_miss",
399 "numa_foreign",
400 "numa_interleave",
401 "numa_local",
402 "numa_other",
403#endif
404
405#ifdef CONFIG_VM_EVENT_COUNTERS
406 "pgpgin",
407 "pgpgout",
408 "pswpin",
409 "pswpout",
410
411 "pgalloc_dma",
412 "pgalloc_dma32",
413 "pgalloc_normal",
414 "pgalloc_high",
415
416 "pgfree",
417 "pgactivate",
418 "pgdeactivate",
419
420 "pgfault",
421 "pgmajfault",
422
423 "pgrefill_dma",
424 "pgrefill_dma32",
425 "pgrefill_normal",
426 "pgrefill_high",
427
428 "pgsteal_dma",
429 "pgsteal_dma32",
430 "pgsteal_normal",
431 "pgsteal_high",
432
433 "pgscan_kswapd_dma",
434 "pgscan_kswapd_dma32",
435 "pgscan_kswapd_normal",
436 "pgscan_kswapd_high",
437
438 "pgscan_direct_dma",
439 "pgscan_direct_dma32",
440 "pgscan_direct_normal",
441 "pgscan_direct_high",
442
443 "pginodesteal",
444 "slabs_scanned",
445 "kswapd_steal",
446 "kswapd_inodesteal",
447 "pageoutrun",
448 "allocstall",
449
450 "pgrotated",
451#endif
452};
453
454/*
455 * Output information about zones in @pgdat.
456 */
457static int zoneinfo_show(struct seq_file *m, void *arg)
458{
459 pg_data_t *pgdat = arg;
460 struct zone *zone;
461 struct zone *node_zones = pgdat->node_zones;
462 unsigned long flags;
463
464 for (zone = node_zones; zone - node_zones < MAX_NR_ZONES; zone++) {
465 int i;
466
467 if (!populated_zone(zone))
468 continue;
469
470 spin_lock_irqsave(&zone->lock, flags);
471 seq_printf(m, "Node %d, zone %8s", pgdat->node_id, zone->name);
472 seq_printf(m,
473 "\n pages free %lu"
474 "\n min %lu"
475 "\n low %lu"
476 "\n high %lu"
477 "\n active %lu"
478 "\n inactive %lu"
479 "\n scanned %lu (a: %lu i: %lu)"
480 "\n spanned %lu"
481 "\n present %lu",
482 zone->free_pages,
483 zone->pages_min,
484 zone->pages_low,
485 zone->pages_high,
486 zone->nr_active,
487 zone->nr_inactive,
488 zone->pages_scanned,
489 zone->nr_scan_active, zone->nr_scan_inactive,
490 zone->spanned_pages,
491 zone->present_pages);
492
493 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
494 seq_printf(m, "\n %-12s %lu", vmstat_text[i],
495 zone_page_state(zone, i));
496
497 seq_printf(m,
498 "\n protection: (%lu",
499 zone->lowmem_reserve[0]);
500 for (i = 1; i < ARRAY_SIZE(zone->lowmem_reserve); i++)
501 seq_printf(m, ", %lu", zone->lowmem_reserve[i]);
502 seq_printf(m,
503 ")"
504 "\n pagesets");
505 for_each_online_cpu(i) {
506 struct per_cpu_pageset *pageset;
507 int j;
508
509 pageset = zone_pcp(zone, i);
510 for (j = 0; j < ARRAY_SIZE(pageset->pcp); j++) {
511 if (pageset->pcp[j].count)
512 break;
513 }
514 if (j == ARRAY_SIZE(pageset->pcp))
515 continue;
516 for (j = 0; j < ARRAY_SIZE(pageset->pcp); j++) {
517 seq_printf(m,
518 "\n cpu: %i pcp: %i"
519 "\n count: %i"
520 "\n high: %i"
521 "\n batch: %i",
522 i, j,
523 pageset->pcp[j].count,
524 pageset->pcp[j].high,
525 pageset->pcp[j].batch);
526 }
527 }
528 seq_printf(m,
529 "\n all_unreclaimable: %u"
530 "\n prev_priority: %i"
531 "\n temp_priority: %i"
532 "\n start_pfn: %lu",
533 zone->all_unreclaimable,
534 zone->prev_priority,
535 zone->temp_priority,
536 zone->zone_start_pfn);
537 spin_unlock_irqrestore(&zone->lock, flags);
538 seq_putc(m, '\n');
539 }
540 return 0;
541}
542
543struct seq_operations zoneinfo_op = {
544 .start = frag_start, /* iterate over all zones. The same as in
545 * fragmentation. */
546 .next = frag_next,
547 .stop = frag_stop,
548 .show = zoneinfo_show,
549};
550
551static void *vmstat_start(struct seq_file *m, loff_t *pos)
552{
553 unsigned long *v;
554#ifdef CONFIG_VM_EVENT_COUNTERS
555 unsigned long *e;
556#endif
557 int i;
558
559 if (*pos >= ARRAY_SIZE(vmstat_text))
560 return NULL;
561
562#ifdef CONFIG_VM_EVENT_COUNTERS
563 v = kmalloc(NR_VM_ZONE_STAT_ITEMS * sizeof(unsigned long)
564 + sizeof(struct vm_event_state), GFP_KERNEL);
565#else
566 v = kmalloc(NR_VM_ZONE_STAT_ITEMS * sizeof(unsigned long),
567 GFP_KERNEL);
568#endif
569 m->private = v;
570 if (!v)
571 return ERR_PTR(-ENOMEM);
572 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
573 v[i] = global_page_state(i);
574#ifdef CONFIG_VM_EVENT_COUNTERS
575 e = v + NR_VM_ZONE_STAT_ITEMS;
576 all_vm_events(e);
577 e[PGPGIN] /= 2; /* sectors -> kbytes */
578 e[PGPGOUT] /= 2;
579#endif
580 return v + *pos;
581}
582
583static void *vmstat_next(struct seq_file *m, void *arg, loff_t *pos)
584{
585 (*pos)++;
586 if (*pos >= ARRAY_SIZE(vmstat_text))
587 return NULL;
588 return (unsigned long *)m->private + *pos;
589}
590
591static int vmstat_show(struct seq_file *m, void *arg)
592{
593 unsigned long *l = arg;
594 unsigned long off = l - (unsigned long *)m->private;
595
596 seq_printf(m, "%s %lu\n", vmstat_text[off], *l);
597 return 0;
598}
599
600static void vmstat_stop(struct seq_file *m, void *arg)
601{
602 kfree(m->private);
603 m->private = NULL;
604}
605
606struct seq_operations vmstat_op = {
607 .start = vmstat_start,
608 .next = vmstat_next,
609 .stop = vmstat_stop,
610 .show = vmstat_show,
611};
612
613#endif /* CONFIG_PROC_FS */
614