mm/vmstat.c

   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 #include <linux/fs.h>
  12 #include <linux/mm.h>
  13 #include <linux/err.h>
  14 #include <linux/module.h>
  15 #include <linux/slab.h>
  16 #include <linux/cpu.h>
  17 #include <linux/vmstat.h>
  18 #include <linux/sched.h>
  19
  20 #ifdef CONFIG_VM_EVENT_COUNTERS
  21 DEFINE_PER_CPU(struct vm_event_state, vm_event_states) = {{0}};
  22 EXPORT_PER_CPU_SYMBOL(vm_event_states);
  23
  24 static void sum_vm_events(unsigned long *ret, const struct cpumask *cpumask)
  25 {
  26         int cpu;
  27         int i;
  28
  29         memset(ret, 0, NR_VM_EVENT_ITEMS * sizeof(unsigned long));
  30
  31         for_each_cpu(cpu, cpumask) {
  32                 struct vm_event_state *this = &per_cpu(vm_event_states, cpu);
  33
  34                 for (i = 0; i < NR_VM_EVENT_ITEMS; i++)
  35                         ret[i] += this->event[i];
  36         }
  37 }
  38
  39 /*
  40  * Accumulate the vm event counters across all CPUs.
  41  * The result is unavoidably approximate - it can change
  42  * during and after execution of this function.
  43 */
  44 void all_vm_events(unsigned long *ret)
  45 {
  46         get_online_cpus();
  47         sum_vm_events(ret, cpu_online_mask);
  48         put_online_cpus();
  49 }
  50 EXPORT_SYMBOL_GPL(all_vm_events);
  51
  52 #ifdef CONFIG_HOTPLUG
  53 /*
  54  * Fold the foreign cpu events into our own.
  55  *
  56  * This is adding to the events on one processor
  57  * but keeps the global counts constant.
  58  */
  59 void vm_events_fold_cpu(int cpu)
  60 {
  61         struct vm_event_state *fold_state = &per_cpu(vm_event_states, cpu);
  62         int i;
  63
  64         for (i = 0; i < NR_VM_EVENT_ITEMS; i++) {
  65                 count_vm_events(i, fold_state->event[i]);
  66                 fold_state->event[i] = 0;
  67         }
  68 }
  69 #endif /* CONFIG_HOTPLUG */
  70
  71 #endif /* CONFIG_VM_EVENT_COUNTERS */
  72
  73 /*
  74  * Manage combined zone based / global counters
  75  *
  76  * vm_stat contains the global counters
  77  */
  78 atomic_long_t vm_stat[NR_VM_ZONE_STAT_ITEMS];
  79 EXPORT_SYMBOL(vm_stat);
  80
  81 #ifdef CONFIG_SMP
  82
  83 static int calculate_threshold(struct zone *zone)
  84 {
  85         int threshold;
  86         int mem;        /* memory in 128 MB units */
  87
  88         /*
  89          * The threshold scales with the number of processors and the amount
  90          * of memory per zone. More memory means that we can defer updates for
  91          * longer, more processors could lead to more contention.
  92          * fls() is used to have a cheap way of logarithmic scaling.
  93          *
  94          * Some sample thresholds:
  95          *
  96          * Threshold    Processors      (fls)   Zonesize        fls(mem+1)
  97          * ------------------------------------------------------------------
  98          * 8            1               1       0.9-1 GB        4
  99          * 16           2               2       0.9-1 GB        4
 100          * 20           2               2       1-2 GB          5
 101          * 24           2               2       2-4 GB          6
 102          * 28           2               2       4-8 GB          7
 103          * 32           2               2       8-16 GB         8
 104          * 4            2               2       <128M           1
 105          * 30           4               3       2-4 GB          5
 106          * 48           4               3       8-16 GB         8
 107          * 32           8               4       1-2 GB          4
 108          * 32           8               4       0.9-1GB         4
 109          * 10           16              5       <128M           1
 110          * 40           16              5       900M            4
 111          * 70           64              7       2-4 GB          5
 112          * 84           64              7       4-8 GB          6
 113          * 108          512             9       4-8 GB          6
 114          * 125          1024            10      8-16 GB         8
 115          * 125          1024            10      16-32 GB        9
 116          */
 117
 118         mem = zone->present_pages >> (27 - PAGE_SHIFT);
 119
 120         threshold = 2 * fls(num_online_cpus()) * (1 + fls(mem));
 121
 122         /*
 123          * Maximum threshold is 125
 124          */
 125         threshold = min(125, threshold);
 126
 127         return threshold;
 128 }
 129
 130 /*
 131  * Refresh the thresholds for each zone.
 132  */
 133 static void refresh_zone_stat_thresholds(void)
 134 {
 135         struct zone *zone;
 136         int cpu;
 137         int threshold;
 138
 139         for_each_populated_zone(zone) {
 140                 threshold = calculate_threshold(zone);
 141
 142                 for_each_online_cpu(cpu)
 143                         per_cpu_ptr(zone->pageset, cpu)->stat_threshold
 144                                                         = threshold;
 145         }
 146 }
 147
 148 /*
 149  * For use when we know that interrupts are disabled.
 150  */
 151 void __mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
 152                                 int delta)
 153 {
 154         struct per_cpu_pageset *pcp = this_cpu_ptr(zone->pageset);
 155
 156         s8 *p = pcp->vm_stat_diff + item;
 157         long x;
 158
 159         x = delta + *p;
 160
 161         if (unlikely(x > pcp->stat_threshold || x < -pcp->stat_threshold)) {
 162                 zone_page_state_add(x, zone, item);
 163                 x = 0;
 164         }
 165         *p = x;
 166 }
 167 EXPORT_SYMBOL(__mod_zone_page_state);
 168
 169 /*
 170  * For an unknown interrupt state
 171  */
 172 void mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
 173                                         int delta)
 174 {
 175         unsigned long flags;
 176
 177         local_irq_save(flags);
 178         __mod_zone_page_state(zone, item, delta);
 179         local_irq_restore(flags);
 180 }
 181 EXPORT_SYMBOL(mod_zone_page_state);
 182
 183 /*
 184  * Optimized increment and decrement functions.
 185  *
 186  * These are only for a single page and therefore can take a struct page *
 187  * argument instead of struct zone *. This allows the inclusion of the code
 188  * generated for page_zone(page) into the optimized functions.
 189  *
 190  * No overflow check is necessary and therefore the differential can be
 191  * incremented or decremented in place which may allow the compilers to
 192  * generate better code.
 193  * The increment or decrement is known and therefore one boundary check can
 194  * be omitted.
 195  *
 196  * NOTE: These functions are very performance sensitive. Change only
 197  * with care.
 198  *
 199  * Some processors have inc/dec instructions that are atomic vs an interrupt.
 200  * However, the code must first determine the differential location in a zone
 201  * based on the processor number and then inc/dec the counter. There is no
 202  * guarantee without disabling preemption that the processor will not change
 203  * in between and therefore the atomicity vs. interrupt cannot be exploited
 204  * in a useful way here.
 205  */
 206 void __inc_zone_state(struct zone *zone, enum zone_stat_item item)
 207 {
 208         struct per_cpu_pageset *pcp = this_cpu_ptr(zone->pageset);
 209         s8 *p = pcp->vm_stat_diff + item;
 210
 211         (*p)++;
 212
 213         if (unlikely(*p > pcp->stat_threshold)) {
 214                 int overstep = pcp->stat_threshold / 2;
 215
 216                 zone_page_state_add(*p + overstep, zone, item);
 217                 *p = -overstep;
 218         }
 219 }
 220
 221 void __inc_zone_page_state(struct page *page, enum zone_stat_item item)
 222 {
 223         __inc_zone_state(page_zone(page), item);
 224 }
 225 EXPORT_SYMBOL(__inc_zone_page_state);
 226
 227 void __dec_zone_state(struct zone *zone, enum zone_stat_item item)
 228 {
 229         struct per_cpu_pageset *pcp = this_cpu_ptr(zone->pageset);
 230         s8 *p = pcp->vm_stat_diff + item;
 231
 232         (*p)--;
 233
 234         if (unlikely(*p < - pcp->stat_threshold)) {
 235                 int overstep = pcp->stat_threshold / 2;
 236
 237                 zone_page_state_add(*p - overstep, zone, item);
 238                 *p = overstep;
 239         }
 240 }
 241
 242 void __dec_zone_page_state(struct page *page, enum zone_stat_item item)
 243 {
 244         __dec_zone_state(page_zone(page), item);
 245 }
 246 EXPORT_SYMBOL(__dec_zone_page_state);
 247
 248 void inc_zone_state(struct zone *zone, enum zone_stat_item item)
 249 {
 250         unsigned long flags;
 251
 252         local_irq_save(flags);
 253         __inc_zone_state(zone, item);
 254         local_irq_restore(flags);
 255 }
 256
 257 void inc_zone_page_state(struct page *page, enum zone_stat_item item)
 258 {
 259         unsigned long flags;
 260         struct zone *zone;
 261
 262         zone = page_zone(page);
 263         local_irq_save(flags);
 264         __inc_zone_state(zone, item);
 265         local_irq_restore(flags);
 266 }
 267 EXPORT_SYMBOL(inc_zone_page_state);
 268
 269 void dec_zone_page_state(struct page *page, enum zone_stat_item item)
 270 {
 271         unsigned long flags;
 272
 273         local_irq_save(flags);
 274         __dec_zone_page_state(page, item);
 275         local_irq_restore(flags);
 276 }
 277 EXPORT_SYMBOL(dec_zone_page_state);
 278
 279 /*
 280  * Update the zone counters for one cpu.
 281  *
 282  * The cpu specified must be either the current cpu or a processor that
 283  * is not online. If it is the current cpu then the execution thread must
 284  * be pinned to the current cpu.
 285  *
 286  * Note that refresh_cpu_vm_stats strives to only access
 287  * node local memory. The per cpu pagesets on remote zones are placed
 288  * in the memory local to the processor using that pageset. So the
 289  * loop over all zones will access a series of cachelines local to
 290  * the processor.
 291  *
 292  * The call to zone_page_state_add updates the cachelines with the
 293  * statistics in the remote zone struct as well as the global cachelines
 294  * with the global counters. These could cause remote node cache line
 295  * bouncing and will have to be only done when necessary.
 296  */
 297 void refresh_cpu_vm_stats(int cpu)
 298 {
 299         struct zone *zone;
 300         int i;
 301         int global_diff[NR_VM_ZONE_STAT_ITEMS] = { 0, };
 302
 303         for_each_populated_zone(zone) {
 304                 struct per_cpu_pageset *p;
 305
 306                 p = per_cpu_ptr(zone->pageset, cpu);
 307
 308                 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
 309                         if (p->vm_stat_diff[i]) {
 310                                 unsigned long flags;
 311                                 int v;
 312
 313                                 local_irq_save(flags);
 314                                 v = p->vm_stat_diff[i];
 315                                 p->vm_stat_diff[i] = 0;
 316                                 local_irq_restore(flags);
 317                                 atomic_long_add(v, &zone->vm_stat[i]);
 318                                 global_diff[i] += v;
 319 #ifdef CONFIG_NUMA
 320                                 /* 3 seconds idle till flush */
 321                                 p->expire = 3;
 322 #endif
 323                         }
 324                 cond_resched();
 325 #ifdef CONFIG_NUMA
 326                 /*
 327                  * Deal with draining the remote pageset of this
 328                  * processor
 329                  *
 330                  * Check if there are pages remaining in this pageset
 331                  * if not then there is nothing to expire.
 332                  */
 333                 if (!p->expire || !p->pcp.count)
 334                         continue;
 335
 336                 /*
 337                  * We never drain zones local to this processor.
 338                  */
 339                 if (zone_to_nid(zone) == numa_node_id()) {
 340                         p->expire = 0;
 341                         continue;
 342                 }
 343
 344                 p->expire--;
 345                 if (p->expire)
 346                         continue;
 347
 348                 if (p->pcp.count)
 349                         drain_zone_pages(zone, &p->pcp);
 350 #endif
 351         }
 352
 353         for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
 354                 if (global_diff[i])
 355                         atomic_long_add(global_diff[i], &vm_stat[i]);
 356 }
 357
 358 #endif
 359
 360 #ifdef CONFIG_NUMA
 361 /*
 362  * zonelist = the list of zones passed to the allocator
 363  * z        = the zone from which the allocation occurred.
 364  *
 365  * Must be called with interrupts disabled.
 366  */
 367 void zone_statistics(struct zone *preferred_zone, struct zone *z)
 368 {
 369         if (z->zone_pgdat == preferred_zone->zone_pgdat) {
 370                 __inc_zone_state(z, NUMA_HIT);
 371         } else {
 372                 __inc_zone_state(z, NUMA_MISS);
 373                 __inc_zone_state(preferred_zone, NUMA_FOREIGN);
 374         }
 375         if (z->node == numa_node_id())
 376                 __inc_zone_state(z, NUMA_LOCAL);
 377         else
 378                 __inc_zone_state(z, NUMA_OTHER);
 379 }
 380 #endif
 381
 382 #ifdef CONFIG_PROC_FS
 383 #include <linux/proc_fs.h>
 384 #include <linux/seq_file.h>
 385
 386 static char * const migratetype_names[MIGRATE_TYPES] = {
 387         "Unmovable",
 388         "Reclaimable",
 389         "Movable",
 390         "Reserve",
 391         "Isolate",
 392 };
 393
 394 static void *frag_start(struct seq_file *m, loff_t *pos)
 395 {
 396         pg_data_t *pgdat;
 397         loff_t node = *pos;
 398         for (pgdat = first_online_pgdat();
 399              pgdat && node;
 400              pgdat = next_online_pgdat(pgdat))
 401                 --node;
 402
 403         return pgdat;
 404 }
 405
 406 static void *frag_next(struct seq_file *m, void *arg, loff_t *pos)
 407 {
 408         pg_data_t *pgdat = (pg_data_t *)arg;
 409
 410         (*pos)++;
 411         return next_online_pgdat(pgdat);
 412 }
 413
 414 static void frag_stop(struct seq_file *m, void *arg)
 415 {
 416 }
 417
 418 /* Walk all the zones in a node and print using a callback */
 419 static void walk_zones_in_node(struct seq_file *m, pg_data_t *pgdat,
 420                 void (*print)(struct seq_file *m, pg_data_t *, struct zone *))
 421 {
 422         struct zone *zone;
 423         struct zone *node_zones = pgdat->node_zones;
 424         unsigned long flags;
 425
 426         for (zone = node_zones; zone - node_zones < MAX_NR_ZONES; ++zone) {
 427                 if (!populated_zone(zone))
 428                         continue;
 429
 430                 spin_lock_irqsave(&zone->lock, flags);
 431                 print(m, pgdat, zone);
 432                 spin_unlock_irqrestore(&zone->lock, flags);
 433         }
 434 }
 435
 436 static void frag_show_print(struct seq_file *m, pg_data_t *pgdat,
 437                                                 struct zone *zone)
 438 {
 439         int order;
 440
 441         seq_printf(m, "Node %d, zone %8s ", pgdat->node_id, zone->name);
 442         for (order = 0; order < MAX_ORDER; ++order)
 443                 seq_printf(m, "%6lu ", zone->free_area[order].nr_free);
 444         seq_putc(m, '\n');
 445 }
 446
 447 /*
 448  * This walks the free areas for each zone.
 449  */
 450 static int frag_show(struct seq_file *m, void *arg)
 451 {
 452         pg_data_t *pgdat = (pg_data_t *)arg;
 453         walk_zones_in_node(m, pgdat, frag_show_print);
 454         return 0;
 455 }
 456
 457 static void pagetypeinfo_showfree_print(struct seq_file *m,
 458                                         pg_data_t *pgdat, struct zone *zone)
 459 {
 460         int order, mtype;
 461
 462         for (mtype = 0; mtype < MIGRATE_TYPES; mtype++) {
 463                 seq_printf(m, "Node %4d, zone %8s, type %12s ",
 464                                         pgdat->node_id,
 465                                         zone->name,
 466                                         migratetype_names[mtype]);
 467                 for (order = 0; order < MAX_ORDER; ++order) {
 468                         unsigned long freecount = 0;
 469                         struct free_area *area;
 470                         struct list_head *curr;
 471
 472                         area = &(zone->free_area[order]);
 473
 474                         list_for_each(curr, &area->free_list[mtype])
 475                                 freecount++;
 476                         seq_printf(m, "%6lu ", freecount);
 477                 }
 478                 seq_putc(m, '\n');
 479         }
 480 }
 481
 482 /* Print out the free pages at each order for each migatetype */
 483 static int pagetypeinfo_showfree(struct seq_file *m, void *arg)
 484 {
 485         int order;
 486         pg_data_t *pgdat = (pg_data_t *)arg;
 487
 488         /* Print header */
 489         seq_printf(m, "%-43s ", "Free pages count per migrate type at order");
 490         for (order = 0; order < MAX_ORDER; ++order)
 491                 seq_printf(m, "%6d ", order);
 492         seq_putc(m, '\n');
 493
 494         walk_zones_in_node(m, pgdat, pagetypeinfo_showfree_print);
 495
 496         return 0;
 497 }
 498
 499 static void pagetypeinfo_showblockcount_print(struct seq_file *m,
 500                                         pg_data_t *pgdat, struct zone *zone)
 501 {
 502         int mtype;
 503         unsigned long pfn;
 504         unsigned long start_pfn = zone->zone_start_pfn;
 505         unsigned long end_pfn = start_pfn + zone->spanned_pages;
 506         unsigned long count[MIGRATE_TYPES] = { 0, };
 507
 508         for (pfn = start_pfn; pfn < end_pfn; pfn += pageblock_nr_pages) {
 509                 struct page *page;
 510
 511                 if (!pfn_valid(pfn))
 512                         continue;
 513
 514                 page = pfn_to_page(pfn);
 515
 516                 /* Watch for unexpected holes punched in the memmap */
 517                 if (!memmap_valid_within(pfn, page, zone))
 518                         continue;
 519
 520                 mtype = get_pageblock_migratetype(page);
 521
 522                 if (mtype < MIGRATE_TYPES)
 523                         count[mtype]++;
 524         }
 525
 526         /* Print counts */
 527         seq_printf(m, "Node %d, zone %8s ", pgdat->node_id, zone->name);
 528         for (mtype = 0; mtype < MIGRATE_TYPES; mtype++)
 529                 seq_printf(m, "%12lu ", count[mtype]);
 530         seq_putc(m, '\n');
 531 }
 532
 533 /* Print out the free pages at each order for each migratetype */
 534 static int pagetypeinfo_showblockcount(struct seq_file *m, void *arg)
 535 {
 536         int mtype;
 537         pg_data_t *pgdat = (pg_data_t *)arg;
 538
 539         seq_printf(m, "\n%-23s", "Number of blocks type ");
 540         for (mtype = 0; mtype < MIGRATE_TYPES; mtype++)
 541                 seq_printf(m, "%12s ", migratetype_names[mtype]);
 542         seq_putc(m, '\n');
 543         walk_zones_in_node(m, pgdat, pagetypeinfo_showblockcount_print);
 544
 545         return 0;
 546 }
 547
 548 /*
 549  * This prints out statistics in relation to grouping pages by mobility.
 550  * It is expensive to collect so do not constantly read the file.
 551  */
 552 static int pagetypeinfo_show(struct seq_file *m, void *arg)
 553 {
 554         pg_data_t *pgdat = (pg_data_t *)arg;
 555
 556         /* check memoryless node */
 557         if (!node_state(pgdat->node_id, N_HIGH_MEMORY))
 558                 return 0;
 559
 560         seq_printf(m, "Page block order: %d\n", pageblock_order);
 561         seq_printf(m, "Pages per block:  %lu\n", pageblock_nr_pages);
 562         seq_putc(m, '\n');
 563         pagetypeinfo_showfree(m, pgdat);
 564         pagetypeinfo_showblockcount(m, pgdat);
 565
 566         return 0;
 567 }
 568
 569 static const struct seq_operations fragmentation_op = {
 570         .start  = frag_start,
 571         .next   = frag_next,
 572         .stop   = frag_stop,
 573         .show   = frag_show,
 574 };
 575
 576 static int fragmentation_open(struct inode *inode, struct file *file)
 577 {
 578         return seq_open(file, &fragmentation_op);
 579 }
 580
 581 static const struct file_operations fragmentation_file_operations = {
 582         .open           = fragmentation_open,
 583         .read           = seq_read,
 584         .llseek         = seq_lseek,
 585         .release        = seq_release,
 586 };
 587
 588 static const struct seq_operations pagetypeinfo_op = {
 589         .start  = frag_start,
 590         .next   = frag_next,
 591         .stop   = frag_stop,
 592         .show   = pagetypeinfo_show,
 593 };
 594
 595 static int pagetypeinfo_open(struct inode *inode, struct file *file)
 596 {
 597         return seq_open(file, &pagetypeinfo_op);
 598 }
 599
 600 static const struct file_operations pagetypeinfo_file_ops = {
 601         .open           = pagetypeinfo_open,
 602         .read           = seq_read,
 603         .llseek         = seq_lseek,
 604         .release        = seq_release,
 605 };
 606
 607 #ifdef CONFIG_ZONE_DMA
 608 #define TEXT_FOR_DMA(xx) xx "_dma",
 609 #else
 610 #define TEXT_FOR_DMA(xx)
 611 #endif
 612
 613 #ifdef CONFIG_ZONE_DMA32
 614 #define TEXT_FOR_DMA32(xx) xx "_dma32",
 615 #else
 616 #define TEXT_FOR_DMA32(xx)
 617 #endif
 618
 619 #ifdef CONFIG_HIGHMEM
 620 #define TEXT_FOR_HIGHMEM(xx) xx "_high",
 621 #else
 622 #define TEXT_FOR_HIGHMEM(xx)
 623 #endif
 624
 625 #define TEXTS_FOR_ZONES(xx) TEXT_FOR_DMA(xx) TEXT_FOR_DMA32(xx) xx "_normal", \
 626                                         TEXT_FOR_HIGHMEM(xx) xx "_movable",
 627
 628 static const char * const vmstat_text[] = {
 629         /* Zoned VM counters */
 630         "nr_free_pages",
 631         "nr_inactive_anon",
 632         "nr_active_anon",
 633         "nr_inactive_file",
 634         "nr_active_file",
 635         "nr_unevictable",
 636         "nr_mlock",
 637         "nr_anon_pages",
 638         "nr_mapped",
 639         "nr_file_pages",
 640         "nr_dirty",
 641         "nr_writeback",
 642         "nr_slab_reclaimable",
 643         "nr_slab_unreclaimable",
 644         "nr_page_table_pages",
 645         "nr_kernel_stack",
 646         "nr_unstable",
 647         "nr_bounce",
 648         "nr_vmscan_write",
 649         "nr_writeback_temp",
 650         "nr_isolated_anon",
 651         "nr_isolated_file",
 652         "nr_shmem",
 653 #ifdef CONFIG_NUMA
 654         "numa_hit",
 655         "numa_miss",
 656         "numa_foreign",
 657         "numa_interleave",
 658         "numa_local",
 659         "numa_other",
 660 #endif
 661
 662 #ifdef CONFIG_VM_EVENT_COUNTERS
 663         "pgpgin",
 664         "pgpgout",
 665         "pswpin",
 666         "pswpout",
 667
 668         TEXTS_FOR_ZONES("pgalloc")
 669
 670         "pgfree",
 671         "pgactivate",
 672         "pgdeactivate",
 673
 674         "pgfault",
 675         "pgmajfault",
 676
 677         TEXTS_FOR_ZONES("pgrefill")
 678         TEXTS_FOR_ZONES("pgsteal")
 679         TEXTS_FOR_ZONES("pgscan_kswapd")
 680         TEXTS_FOR_ZONES("pgscan_direct")
 681
 682 #ifdef CONFIG_NUMA
 683         "zone_reclaim_failed",
 684 #endif
 685         "pginodesteal",
 686         "slabs_scanned",
 687         "kswapd_steal",
 688         "kswapd_inodesteal",
 689         "kswapd_low_wmark_hit_quickly",
 690         "kswapd_high_wmark_hit_quickly",
 691         "kswapd_skip_congestion_wait",
 692         "pageoutrun",
 693         "allocstall",
 694
 695         "pgrotated",
 696 #ifdef CONFIG_HUGETLB_PAGE
 697         "htlb_buddy_alloc_success",
 698         "htlb_buddy_alloc_fail",
 699 #endif
 700         "unevictable_pgs_culled",
 701         "unevictable_pgs_scanned",
 702         "unevictable_pgs_rescued",
 703         "unevictable_pgs_mlocked",
 704         "unevictable_pgs_munlocked",
 705         "unevictable_pgs_cleared",
 706         "unevictable_pgs_stranded",
 707         "unevictable_pgs_mlockfreed",
 708 #endif
 709 };
 710
 711 static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat,
 712                                                         struct zone *zone)
 713 {
 714         int i;
 715         seq_printf(m, "Node %d, zone %8s", pgdat->node_id, zone->name);
 716         seq_printf(m,
 717                    "\n  pages free     %lu"
 718                    "\n        min      %lu"
 719                    "\n        low      %lu"
 720                    "\n        high     %lu"
 721                    "\n        scanned  %lu"
 722                    "\n        spanned  %lu"
 723                    "\n        present  %lu",
 724                    zone_page_state(zone, NR_FREE_PAGES),
 725                    min_wmark_pages(zone),
 726                    low_wmark_pages(zone),
 727                    high_wmark_pages(zone),
 728                    zone->pages_scanned,
 729                    zone->spanned_pages,
 730                    zone->present_pages);
 731
 732         for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
 733                 seq_printf(m, "\n    %-12s %lu", vmstat_text[i],
 734                                 zone_page_state(zone, i));
 735
 736         seq_printf(m,
 737                    "\n        protection: (%lu",
 738                    zone->lowmem_reserve[0]);
 739         for (i = 1; i < ARRAY_SIZE(zone->lowmem_reserve); i++)
 740                 seq_printf(m, ", %lu", zone->lowmem_reserve[i]);
 741         seq_printf(m,
 742                    ")"
 743                    "\n  pagesets");
 744         for_each_online_cpu(i) {
 745                 struct per_cpu_pageset *pageset;
 746
 747                 pageset = per_cpu_ptr(zone->pageset, i);
 748                 seq_printf(m,
 749                            "\n    cpu: %i"
 750                            "\n              count: %i"
 751                            "\n              high:  %i"
 752                            "\n              batch: %i",
 753                            i,
 754                            pageset->pcp.count,
 755                            pageset->pcp.high,
 756                            pageset->pcp.batch);
 757 #ifdef CONFIG_SMP
 758                 seq_printf(m, "\n  vm stats threshold: %d",
 759                                 pageset->stat_threshold);
 760 #endif
 761         }
 762         seq_printf(m,
 763                    "\n  all_unreclaimable: %u"
 764                    "\n  prev_priority:     %i"
 765                    "\n  start_pfn:         %lu"
 766                    "\n  inactive_ratio:    %u",
 767                    zone->all_unreclaimable,
 768                    zone->prev_priority,
 769                    zone->zone_start_pfn,
 770                    zone->inactive_ratio);
 771         seq_putc(m, '\n');
 772 }
 773
 774 /*
 775  * Output information about zones in @pgdat.
 776  */
 777 static int zoneinfo_show(struct seq_file *m, void *arg)
 778 {
 779         pg_data_t *pgdat = (pg_data_t *)arg;
 780         walk_zones_in_node(m, pgdat, zoneinfo_show_print);
 781         return 0;
 782 }
 783
 784 static const struct seq_operations zoneinfo_op = {
 785         .start  = frag_start, /* iterate over all zones. The same as in
 786                                * fragmentation. */
 787         .next   = frag_next,
 788         .stop   = frag_stop,
 789         .show   = zoneinfo_show,
 790 };
 791
 792 static int zoneinfo_open(struct inode *inode, struct file *file)
 793 {
 794         return seq_open(file, &zoneinfo_op);
 795 }
 796
 797 static const struct file_operations proc_zoneinfo_file_operations = {
 798         .open           = zoneinfo_open,
 799         .read           = seq_read,
 800         .llseek         = seq_lseek,
 801         .release        = seq_release,
 802 };
 803
 804 static void *vmstat_start(struct seq_file *m, loff_t *pos)
 805 {
 806         unsigned long *v;
 807 #ifdef CONFIG_VM_EVENT_COUNTERS
 808         unsigned long *e;
 809 #endif
 810         int i;
 811
 812         if (*pos >= ARRAY_SIZE(vmstat_text))
 813                 return NULL;
 814
 815 #ifdef CONFIG_VM_EVENT_COUNTERS
 816         v = kmalloc(NR_VM_ZONE_STAT_ITEMS * sizeof(unsigned long)
 817                         + sizeof(struct vm_event_state), GFP_KERNEL);
 818 #else
 819         v = kmalloc(NR_VM_ZONE_STAT_ITEMS * sizeof(unsigned long),
 820                         GFP_KERNEL);
 821 #endif
 822         m->private = v;
 823         if (!v)
 824                 return ERR_PTR(-ENOMEM);
 825         for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
 826                 v[i] = global_page_state(i);
 827 #ifdef CONFIG_VM_EVENT_COUNTERS
 828         e = v + NR_VM_ZONE_STAT_ITEMS;
 829         all_vm_events(e);
 830         e[PGPGIN] /= 2;         /* sectors -> kbytes */
 831         e[PGPGOUT] /= 2;
 832 #endif
 833         return v + *pos;
 834 }
 835
 836 static void *vmstat_next(struct seq_file *m, void *arg, loff_t *pos)
 837 {
 838         (*pos)++;
 839         if (*pos >= ARRAY_SIZE(vmstat_text))
 840                 return NULL;
 841         return (unsigned long *)m->private + *pos;
 842 }
 843
 844 static int vmstat_show(struct seq_file *m, void *arg)
 845 {
 846         unsigned long *l = arg;
 847         unsigned long off = l - (unsigned long *)m->private;
 848
 849         seq_printf(m, "%s %lu\n", vmstat_text[off], *l);
 850         return 0;
 851 }
 852
 853 static void vmstat_stop(struct seq_file *m, void *arg)
 854 {
 855         kfree(m->private);
 856         m->private = NULL;
 857 }
 858
 859 static const struct seq_operations vmstat_op = {
 860         .start  = vmstat_start,
 861         .next   = vmstat_next,
 862         .stop   = vmstat_stop,
 863         .show   = vmstat_show,
 864 };
 865
 866 static int vmstat_open(struct inode *inode, struct file *file)
 867 {
 868         return seq_open(file, &vmstat_op);
 869 }
 870
 871 static const struct file_operations proc_vmstat_file_operations = {
 872         .open           = vmstat_open,
 873         .read           = seq_read,
 874         .llseek         = seq_lseek,
 875         .release        = seq_release,
 876 };
 877 #endif /* CONFIG_PROC_FS */
 878
 879 #ifdef CONFIG_SMP
 880 static DEFINE_PER_CPU(struct delayed_work, vmstat_work);
 881 int sysctl_stat_interval __read_mostly = HZ;
 882
 883 static void vmstat_update(struct work_struct *w)
 884 {
 885         refresh_cpu_vm_stats(smp_processor_id());
 886         schedule_delayed_work(&__get_cpu_var(vmstat_work),
 887                 round_jiffies_relative(sysctl_stat_interval));
 888 }
 889
 890 static void __cpuinit start_cpu_timer(int cpu)
 891 {
 892         struct delayed_work *work = &per_cpu(vmstat_work, cpu);
 893
 894         INIT_DELAYED_WORK_DEFERRABLE(work, vmstat_update);
 895         schedule_delayed_work_on(cpu, work, __round_jiffies_relative(HZ, cpu));
 896 }
 897
 898 /*
 899  * Use the cpu notifier to insure that the thresholds are recalculated
 900  * when necessary.
 901  */
 902 static int __cpuinit vmstat_cpuup_callback(struct notifier_block *nfb,
 903                 unsigned long action,
 904                 void *hcpu)
 905 {
 906         long cpu = (long)hcpu;
 907
 908         switch (action) {
 909         case CPU_ONLINE:
 910         case CPU_ONLINE_FROZEN:
 911                 start_cpu_timer(cpu);
 912                 node_set_state(cpu_to_node(cpu), N_CPU);
 913                 break;
 914         case CPU_DOWN_PREPARE:
 915         case CPU_DOWN_PREPARE_FROZEN:
 916                 cancel_rearming_delayed_work(&per_cpu(vmstat_work, cpu));
 917                 per_cpu(vmstat_work, cpu).work.func = NULL;
 918                 break;
 919         case CPU_DOWN_FAILED:
 920         case CPU_DOWN_FAILED_FROZEN:
 921                 start_cpu_timer(cpu);
 922                 break;
 923         case CPU_DEAD:
 924         case CPU_DEAD_FROZEN:
 925                 refresh_zone_stat_thresholds();
 926                 break;
 927         default:
 928                 break;
 929         }
 930         return NOTIFY_OK;
 931 }
 932
 933 static struct notifier_block __cpuinitdata vmstat_notifier =
 934         { &vmstat_cpuup_callback, NULL, 0 };
 935 #endif
 936
 937 static int __init setup_vmstat(void)
 938 {
 939 #ifdef CONFIG_SMP
 940         int cpu;
 941
 942         refresh_zone_stat_thresholds();
 943         register_cpu_notifier(&vmstat_notifier);
 944
 945         for_each_online_cpu(cpu)
 946                 start_cpu_timer(cpu);
 947 #endif
 948 #ifdef CONFIG_PROC_FS
 949         proc_create("buddyinfo", S_IRUGO, NULL, &fragmentation_file_operations);
 950         proc_create("pagetypeinfo", S_IRUGO, NULL, &pagetypeinfo_file_ops);
 951         proc_create("vmstat", S_IRUGO, NULL, &proc_vmstat_file_operations);
 952         proc_create("zoneinfo", S_IRUGO, NULL, &proc_zoneinfo_file_operations);
 953 #endif
 954         return 0;
 955 }
 956 module_init(setup_vmstat)