vmstat.c 13.2 KB
Newer Older
1 2 3 4 5
/*
 *  linux/mm/vmstat.c
 *
 *  Manages VM statistics
 *  Copyright (C) 1991, 1992, 1993, 1994  Linus Torvalds
6 7 8 9
 *
 *  zoned VM statistics
 *  Copyright (C) 2006 Silicon Graphics, Inc.,
 *		Christoph Lameter <christoph@lameter.com>
10 11 12 13
 */

#include <linux/config.h>
#include <linux/mm.h>
14
#include <linux/module.h>
15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48

void __get_zone_counts(unsigned long *active, unsigned long *inactive,
			unsigned long *free, struct pglist_data *pgdat)
{
	struct zone *zones = pgdat->node_zones;
	int i;

	*active = 0;
	*inactive = 0;
	*free = 0;
	for (i = 0; i < MAX_NR_ZONES; i++) {
		*active += zones[i].nr_active;
		*inactive += zones[i].nr_inactive;
		*free += zones[i].free_pages;
	}
}

void get_zone_counts(unsigned long *active,
		unsigned long *inactive, unsigned long *free)
{
	struct pglist_data *pgdat;

	*active = 0;
	*inactive = 0;
	*free = 0;
	for_each_online_pgdat(pgdat) {
		unsigned long l, m, n;
		__get_zone_counts(&l, &m, &n, pgdat);
		*active += l;
		*inactive += m;
		*free += n;
	}
}

49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105
#ifdef CONFIG_VM_EVENT_COUNTERS
DEFINE_PER_CPU(struct vm_event_state, vm_event_states) = {{0}};
EXPORT_PER_CPU_SYMBOL(vm_event_states);

static void sum_vm_events(unsigned long *ret, cpumask_t *cpumask)
{
	int cpu = 0;
	int i;

	memset(ret, 0, NR_VM_EVENT_ITEMS * sizeof(unsigned long));

	cpu = first_cpu(*cpumask);
	while (cpu < NR_CPUS) {
		struct vm_event_state *this = &per_cpu(vm_event_states, cpu);

		cpu = next_cpu(cpu, *cpumask);

		if (cpu < NR_CPUS)
			prefetch(&per_cpu(vm_event_states, cpu));


		for (i = 0; i < NR_VM_EVENT_ITEMS; i++)
			ret[i] += this->event[i];
	}
}

/*
 * Accumulate the vm event counters across all CPUs.
 * The result is unavoidably approximate - it can change
 * during and after execution of this function.
*/
void all_vm_events(unsigned long *ret)
{
	sum_vm_events(ret, &cpu_online_map);
}

#ifdef CONFIG_HOTPLUG
/*
 * Fold the foreign cpu events into our own.
 *
 * This is adding to the events on one processor
 * but keeps the global counts constant.
 */
void vm_events_fold_cpu(int cpu)
{
	struct vm_event_state *fold_state = &per_cpu(vm_event_states, cpu);
	int i;

	for (i = 0; i < NR_VM_EVENT_ITEMS; i++) {
		count_vm_events(i, fold_state->event[i]);
		fold_state->event[i] = 0;
	}
}
#endif /* CONFIG_HOTPLUG */

#endif /* CONFIG_VM_EVENT_COUNTERS */

106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184
/*
 * Manage combined zone based / global counters
 *
 * vm_stat contains the global counters
 */
atomic_long_t vm_stat[NR_VM_ZONE_STAT_ITEMS];
EXPORT_SYMBOL(vm_stat);

#ifdef CONFIG_SMP

#define STAT_THRESHOLD 32

/*
 * Determine pointer to currently valid differential byte given a zone and
 * the item number.
 *
 * Preemption must be off
 */
static inline s8 *diff_pointer(struct zone *zone, enum zone_stat_item item)
{
	return &zone_pcp(zone, smp_processor_id())->vm_stat_diff[item];
}

/*
 * For use when we know that interrupts are disabled.
 */
void __mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
				int delta)
{
	s8 *p;
	long x;

	p = diff_pointer(zone, item);
	x = delta + *p;

	if (unlikely(x > STAT_THRESHOLD || x < -STAT_THRESHOLD)) {
		zone_page_state_add(x, zone, item);
		x = 0;
	}

	*p = x;
}
EXPORT_SYMBOL(__mod_zone_page_state);

/*
 * For an unknown interrupt state
 */
void mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
					int delta)
{
	unsigned long flags;

	local_irq_save(flags);
	__mod_zone_page_state(zone, item, delta);
	local_irq_restore(flags);
}
EXPORT_SYMBOL(mod_zone_page_state);

/*
 * Optimized increment and decrement functions.
 *
 * These are only for a single page and therefore can take a struct page *
 * argument instead of struct zone *. This allows the inclusion of the code
 * generated for page_zone(page) into the optimized functions.
 *
 * No overflow check is necessary and therefore the differential can be
 * incremented or decremented in place which may allow the compilers to
 * generate better code.
 *
 * The increment or decrement is known and therefore one boundary check can
 * be omitted.
 *
 * Some processors have inc/dec instructions that are atomic vs an interrupt.
 * However, the code must first determine the differential location in a zone
 * based on the processor number and then inc/dec the counter. There is no
 * guarantee without disabling preemption that the processor will not change
 * in between and therefore the atomicity vs. interrupt cannot be exploited
 * in a useful way here.
 */
185
static void __inc_zone_state(struct zone *zone, enum zone_stat_item item)
186 187 188 189 190 191 192 193 194 195
{
	s8 *p = diff_pointer(zone, item);

	(*p)++;

	if (unlikely(*p > STAT_THRESHOLD)) {
		zone_page_state_add(*p, zone, item);
		*p = 0;
	}
}
196 197 198 199 200

void __inc_zone_page_state(struct page *page, enum zone_stat_item item)
{
	__inc_zone_state(page_zone(page), item);
}
201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216
EXPORT_SYMBOL(__inc_zone_page_state);

void __dec_zone_page_state(struct page *page, enum zone_stat_item item)
{
	struct zone *zone = page_zone(page);
	s8 *p = diff_pointer(zone, item);

	(*p)--;

	if (unlikely(*p < -STAT_THRESHOLD)) {
		zone_page_state_add(*p, zone, item);
		*p = 0;
	}
}
EXPORT_SYMBOL(__dec_zone_page_state);

217 218 219 220 221 222 223 224 225
void inc_zone_state(struct zone *zone, enum zone_stat_item item)
{
	unsigned long flags;

	local_irq_save(flags);
	__inc_zone_state(zone, item);
	local_irq_restore(flags);
}

226 227 228 229 230 231 232
void inc_zone_page_state(struct page *page, enum zone_stat_item item)
{
	unsigned long flags;
	struct zone *zone;

	zone = page_zone(page);
	local_irq_save(flags);
233
	__inc_zone_state(zone, item);
234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301
	local_irq_restore(flags);
}
EXPORT_SYMBOL(inc_zone_page_state);

void dec_zone_page_state(struct page *page, enum zone_stat_item item)
{
	unsigned long flags;
	struct zone *zone;
	s8 *p;

	zone = page_zone(page);
	local_irq_save(flags);
	p = diff_pointer(zone, item);

	(*p)--;

	if (unlikely(*p < -STAT_THRESHOLD)) {
		zone_page_state_add(*p, zone, item);
		*p = 0;
	}
	local_irq_restore(flags);
}
EXPORT_SYMBOL(dec_zone_page_state);

/*
 * Update the zone counters for one cpu.
 */
void refresh_cpu_vm_stats(int cpu)
{
	struct zone *zone;
	int i;
	unsigned long flags;

	for_each_zone(zone) {
		struct per_cpu_pageset *pcp;

		pcp = zone_pcp(zone, cpu);

		for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
			if (pcp->vm_stat_diff[i]) {
				local_irq_save(flags);
				zone_page_state_add(pcp->vm_stat_diff[i],
					zone, i);
				pcp->vm_stat_diff[i] = 0;
				local_irq_restore(flags);
			}
	}
}

static void __refresh_cpu_vm_stats(void *dummy)
{
	refresh_cpu_vm_stats(smp_processor_id());
}

/*
 * Consolidate all counters.
 *
 * Note that the result is less inaccurate but still inaccurate
 * if concurrent processes are allowed to run.
 */
void refresh_vm_stats(void)
{
	on_each_cpu(__refresh_cpu_vm_stats, NULL, 0, 1);
}
EXPORT_SYMBOL(refresh_vm_stats);

#endif

302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323
#ifdef CONFIG_NUMA
/*
 * zonelist = the list of zones passed to the allocator
 * z 	    = the zone from which the allocation occurred.
 *
 * Must be called with interrupts disabled.
 */
void zone_statistics(struct zonelist *zonelist, struct zone *z)
{
	if (z->zone_pgdat == zonelist->zones[0]->zone_pgdat) {
		__inc_zone_state(z, NUMA_HIT);
	} else {
		__inc_zone_state(z, NUMA_MISS);
		__inc_zone_state(zonelist->zones[0], NUMA_FOREIGN);
	}
	if (z->zone_pgdat == NODE_DATA(numa_node_id()))
		__inc_zone_state(z, NUMA_LOCAL);
	else
		__inc_zone_state(z, NUMA_OTHER);
}
#endif

324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384
#ifdef CONFIG_PROC_FS

#include <linux/seq_file.h>

static void *frag_start(struct seq_file *m, loff_t *pos)
{
	pg_data_t *pgdat;
	loff_t node = *pos;
	for (pgdat = first_online_pgdat();
	     pgdat && node;
	     pgdat = next_online_pgdat(pgdat))
		--node;

	return pgdat;
}

static void *frag_next(struct seq_file *m, void *arg, loff_t *pos)
{
	pg_data_t *pgdat = (pg_data_t *)arg;

	(*pos)++;
	return next_online_pgdat(pgdat);
}

static void frag_stop(struct seq_file *m, void *arg)
{
}

/*
 * This walks the free areas for each zone.
 */
static int frag_show(struct seq_file *m, void *arg)
{
	pg_data_t *pgdat = (pg_data_t *)arg;
	struct zone *zone;
	struct zone *node_zones = pgdat->node_zones;
	unsigned long flags;
	int order;

	for (zone = node_zones; zone - node_zones < MAX_NR_ZONES; ++zone) {
		if (!populated_zone(zone))
			continue;

		spin_lock_irqsave(&zone->lock, flags);
		seq_printf(m, "Node %d, zone %8s ", pgdat->node_id, zone->name);
		for (order = 0; order < MAX_ORDER; ++order)
			seq_printf(m, "%6lu ", zone->free_area[order].nr_free);
		spin_unlock_irqrestore(&zone->lock, flags);
		seq_putc(m, '\n');
	}
	return 0;
}

struct seq_operations fragmentation_op = {
	.start	= frag_start,
	.next	= frag_next,
	.stop	= frag_stop,
	.show	= frag_show,
};

static 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

396 397 398 399 400 401 402 403 404
#ifdef CONFIG_NUMA
	"numa_hit",
	"numa_miss",
	"numa_foreign",
	"numa_interleave",
	"numa_local",
	"numa_other",
#endif

405
#ifdef CONFIG_VM_EVENT_COUNTERS
406 407 408 409 410 411
	"pgpgin",
	"pgpgout",
	"pswpin",
	"pswpout",

	"pgalloc_dma",
412 413 414
	"pgalloc_dma32",
	"pgalloc_normal",
	"pgalloc_high",
415 416 417 418 419 420 421 422 423

	"pgfree",
	"pgactivate",
	"pgdeactivate",

	"pgfault",
	"pgmajfault",

	"pgrefill_dma",
424 425 426
	"pgrefill_dma32",
	"pgrefill_normal",
	"pgrefill_high",
427 428

	"pgsteal_dma",
429 430 431
	"pgsteal_dma32",
	"pgsteal_normal",
	"pgsteal_high",
432 433

	"pgscan_kswapd_dma",
434 435 436
	"pgscan_kswapd_dma32",
	"pgscan_kswapd_normal",
	"pgscan_kswapd_high",
437 438

	"pgscan_direct_dma",
439 440 441
	"pgscan_direct_dma32",
	"pgscan_direct_normal",
	"pgscan_direct_high",
442 443 444 445 446 447 448 449 450

	"pginodesteal",
	"slabs_scanned",
	"kswapd_steal",
	"kswapd_inodesteal",
	"pageoutrun",
	"allocstall",

	"pgrotated",
451
#endif
452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491
};

/*
 * Output information about zones in @pgdat.
 */
static int zoneinfo_show(struct seq_file *m, void *arg)
{
	pg_data_t *pgdat = arg;
	struct zone *zone;
	struct zone *node_zones = pgdat->node_zones;
	unsigned long flags;

	for (zone = node_zones; zone - node_zones < MAX_NR_ZONES; zone++) {
		int i;

		if (!populated_zone(zone))
			continue;

		spin_lock_irqsave(&zone->lock, flags);
		seq_printf(m, "Node %d, zone %8s", pgdat->node_id, zone->name);
		seq_printf(m,
			   "\n  pages free     %lu"
			   "\n        min      %lu"
			   "\n        low      %lu"
			   "\n        high     %lu"
			   "\n        active   %lu"
			   "\n        inactive %lu"
			   "\n        scanned  %lu (a: %lu i: %lu)"
			   "\n        spanned  %lu"
			   "\n        present  %lu",
			   zone->free_pages,
			   zone->pages_min,
			   zone->pages_low,
			   zone->pages_high,
			   zone->nr_active,
			   zone->nr_inactive,
			   zone->pages_scanned,
			   zone->nr_scan_active, zone->nr_scan_inactive,
			   zone->spanned_pages,
			   zone->present_pages);
492 493 494 495 496

		for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
			seq_printf(m, "\n    %-12s %lu", vmstat_text[i],
					zone_page_state(zone, i));

497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552
		seq_printf(m,
			   "\n        protection: (%lu",
			   zone->lowmem_reserve[0]);
		for (i = 1; i < ARRAY_SIZE(zone->lowmem_reserve); i++)
			seq_printf(m, ", %lu", zone->lowmem_reserve[i]);
		seq_printf(m,
			   ")"
			   "\n  pagesets");
		for_each_online_cpu(i) {
			struct per_cpu_pageset *pageset;
			int j;

			pageset = zone_pcp(zone, i);
			for (j = 0; j < ARRAY_SIZE(pageset->pcp); j++) {
				if (pageset->pcp[j].count)
					break;
			}
			if (j == ARRAY_SIZE(pageset->pcp))
				continue;
			for (j = 0; j < ARRAY_SIZE(pageset->pcp); j++) {
				seq_printf(m,
					   "\n    cpu: %i pcp: %i"
					   "\n              count: %i"
					   "\n              high:  %i"
					   "\n              batch: %i",
					   i, j,
					   pageset->pcp[j].count,
					   pageset->pcp[j].high,
					   pageset->pcp[j].batch);
			}
		}
		seq_printf(m,
			   "\n  all_unreclaimable: %u"
			   "\n  prev_priority:     %i"
			   "\n  temp_priority:     %i"
			   "\n  start_pfn:         %lu",
			   zone->all_unreclaimable,
			   zone->prev_priority,
			   zone->temp_priority,
			   zone->zone_start_pfn);
		spin_unlock_irqrestore(&zone->lock, flags);
		seq_putc(m, '\n');
	}
	return 0;
}

struct seq_operations zoneinfo_op = {
	.start	= frag_start, /* iterate over all zones. The same as in
			       * fragmentation. */
	.next	= frag_next,
	.stop	= frag_stop,
	.show	= zoneinfo_show,
};

static void *vmstat_start(struct seq_file *m, loff_t *pos)
{
553
	unsigned long *v;
554 555 556
#ifdef CONFIG_VM_EVENT_COUNTERS
	unsigned long *e;
#endif
557
	int i;
558 559 560 561

	if (*pos >= ARRAY_SIZE(vmstat_text))
		return NULL;

562
#ifdef CONFIG_VM_EVENT_COUNTERS
563
	v = kmalloc(NR_VM_ZONE_STAT_ITEMS * sizeof(unsigned long)
564 565 566 567 568
			+ sizeof(struct vm_event_state), GFP_KERNEL);
#else
	v = kmalloc(NR_VM_ZONE_STAT_ITEMS * sizeof(unsigned long),
			GFP_KERNEL);
#endif
569 570
	m->private = v;
	if (!v)
571
		return ERR_PTR(-ENOMEM);
572 573
	for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
		v[i] = global_page_state(i);
574 575 576 577 578 579
#ifdef CONFIG_VM_EVENT_COUNTERS
	e = v + NR_VM_ZONE_STAT_ITEMS;
	all_vm_events(e);
	e[PGPGIN] /= 2;		/* sectors -> kbytes */
	e[PGPGOUT] /= 2;
#endif
580
	return v + *pos;
581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614
}

static void *vmstat_next(struct seq_file *m, void *arg, loff_t *pos)
{
	(*pos)++;
	if (*pos >= ARRAY_SIZE(vmstat_text))
		return NULL;
	return (unsigned long *)m->private + *pos;
}

static int vmstat_show(struct seq_file *m, void *arg)
{
	unsigned long *l = arg;
	unsigned long off = l - (unsigned long *)m->private;

	seq_printf(m, "%s %lu\n", vmstat_text[off], *l);
	return 0;
}

static void vmstat_stop(struct seq_file *m, void *arg)
{
	kfree(m->private);
	m->private = NULL;
}

struct seq_operations vmstat_op = {
	.start	= vmstat_start,
	.next	= vmstat_next,
	.stop	= vmstat_stop,
	.show	= vmstat_show,
};

#endif /* CONFIG_PROC_FS */