sysfs: Fail bin file mmap if vma close is implemented.
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / mm / vmstat.c
blob355a9e669aaa800d62fa31d2b83110bf76cce9d7
1 /*
2 * linux/mm/vmstat.c
4 * Manages VM statistics
5 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
7 * zoned VM statistics
8 * Copyright (C) 2006 Silicon Graphics, Inc.,
9 * Christoph Lameter <christoph@lameter.com>
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 #include <linux/math64.h>
21 #ifdef CONFIG_VM_EVENT_COUNTERS
22 DEFINE_PER_CPU(struct vm_event_state, vm_event_states) = {{0}};
23 EXPORT_PER_CPU_SYMBOL(vm_event_states);
25 static void sum_vm_events(unsigned long *ret)
27 int cpu;
28 int i;
30 memset(ret, 0, NR_VM_EVENT_ITEMS * sizeof(unsigned long));
32 for_each_online_cpu(cpu) {
33 struct vm_event_state *this = &per_cpu(vm_event_states, cpu);
35 for (i = 0; i < NR_VM_EVENT_ITEMS; i++)
36 ret[i] += this->event[i];
41 * Accumulate the vm event counters across all CPUs.
42 * The result is unavoidably approximate - it can change
43 * during and after execution of this function.
45 void all_vm_events(unsigned long *ret)
47 get_online_cpus();
48 sum_vm_events(ret);
49 put_online_cpus();
51 EXPORT_SYMBOL_GPL(all_vm_events);
53 #ifdef CONFIG_HOTPLUG
55 * Fold the foreign cpu events into our own.
57 * This is adding to the events on one processor
58 * but keeps the global counts constant.
60 void vm_events_fold_cpu(int cpu)
62 struct vm_event_state *fold_state = &per_cpu(vm_event_states, cpu);
63 int i;
65 for (i = 0; i < NR_VM_EVENT_ITEMS; i++) {
66 count_vm_events(i, fold_state->event[i]);
67 fold_state->event[i] = 0;
70 #endif /* CONFIG_HOTPLUG */
72 #endif /* CONFIG_VM_EVENT_COUNTERS */
75 * Manage combined zone based / global counters
77 * vm_stat contains the global counters
79 atomic_long_t vm_stat[NR_VM_ZONE_STAT_ITEMS];
80 EXPORT_SYMBOL(vm_stat);
82 #ifdef CONFIG_SMP
84 static int calculate_threshold(struct zone *zone)
86 int threshold;
87 int mem; /* memory in 128 MB units */
90 * The threshold scales with the number of processors and the amount
91 * of memory per zone. More memory means that we can defer updates for
92 * longer, more processors could lead to more contention.
93 * fls() is used to have a cheap way of logarithmic scaling.
95 * Some sample thresholds:
97 * Threshold Processors (fls) Zonesize fls(mem+1)
98 * ------------------------------------------------------------------
99 * 8 1 1 0.9-1 GB 4
100 * 16 2 2 0.9-1 GB 4
101 * 20 2 2 1-2 GB 5
102 * 24 2 2 2-4 GB 6
103 * 28 2 2 4-8 GB 7
104 * 32 2 2 8-16 GB 8
105 * 4 2 2 <128M 1
106 * 30 4 3 2-4 GB 5
107 * 48 4 3 8-16 GB 8
108 * 32 8 4 1-2 GB 4
109 * 32 8 4 0.9-1GB 4
110 * 10 16 5 <128M 1
111 * 40 16 5 900M 4
112 * 70 64 7 2-4 GB 5
113 * 84 64 7 4-8 GB 6
114 * 108 512 9 4-8 GB 6
115 * 125 1024 10 8-16 GB 8
116 * 125 1024 10 16-32 GB 9
119 mem = zone->present_pages >> (27 - PAGE_SHIFT);
121 threshold = 2 * fls(num_online_cpus()) * (1 + fls(mem));
124 * Maximum threshold is 125
126 threshold = min(125, threshold);
128 return threshold;
132 * Refresh the thresholds for each zone.
134 static void refresh_zone_stat_thresholds(void)
136 struct zone *zone;
137 int cpu;
138 int threshold;
140 for_each_populated_zone(zone) {
141 unsigned long max_drift, tolerate_drift;
143 threshold = calculate_threshold(zone);
145 for_each_online_cpu(cpu)
146 per_cpu_ptr(zone->pageset, cpu)->stat_threshold
147 = threshold;
150 * Only set percpu_drift_mark if there is a danger that
151 * NR_FREE_PAGES reports the low watermark is ok when in fact
152 * the min watermark could be breached by an allocation
154 tolerate_drift = low_wmark_pages(zone) - min_wmark_pages(zone);
155 max_drift = num_online_cpus() * threshold;
156 if (max_drift > tolerate_drift)
157 zone->percpu_drift_mark = high_wmark_pages(zone) +
158 max_drift;
163 * For use when we know that interrupts are disabled.
165 void __mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
166 int delta)
168 struct per_cpu_pageset *pcp = this_cpu_ptr(zone->pageset);
170 s8 *p = pcp->vm_stat_diff + item;
171 long x;
173 x = delta + *p;
175 if (unlikely(x > pcp->stat_threshold || x < -pcp->stat_threshold)) {
176 zone_page_state_add(x, zone, item);
177 x = 0;
179 *p = x;
181 EXPORT_SYMBOL(__mod_zone_page_state);
184 * For an unknown interrupt state
186 void mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
187 int delta)
189 unsigned long flags;
191 local_irq_save(flags);
192 __mod_zone_page_state(zone, item, delta);
193 local_irq_restore(flags);
195 EXPORT_SYMBOL(mod_zone_page_state);
198 * Optimized increment and decrement functions.
200 * These are only for a single page and therefore can take a struct page *
201 * argument instead of struct zone *. This allows the inclusion of the code
202 * generated for page_zone(page) into the optimized functions.
204 * No overflow check is necessary and therefore the differential can be
205 * incremented or decremented in place which may allow the compilers to
206 * generate better code.
207 * The increment or decrement is known and therefore one boundary check can
208 * be omitted.
210 * NOTE: These functions are very performance sensitive. Change only
211 * with care.
213 * Some processors have inc/dec instructions that are atomic vs an interrupt.
214 * However, the code must first determine the differential location in a zone
215 * based on the processor number and then inc/dec the counter. There is no
216 * guarantee without disabling preemption that the processor will not change
217 * in between and therefore the atomicity vs. interrupt cannot be exploited
218 * in a useful way here.
220 void __inc_zone_state(struct zone *zone, enum zone_stat_item item)
222 struct per_cpu_pageset *pcp = this_cpu_ptr(zone->pageset);
223 s8 *p = pcp->vm_stat_diff + item;
225 (*p)++;
227 if (unlikely(*p > pcp->stat_threshold)) {
228 int overstep = pcp->stat_threshold / 2;
230 zone_page_state_add(*p + overstep, zone, item);
231 *p = -overstep;
235 void __inc_zone_page_state(struct page *page, enum zone_stat_item item)
237 __inc_zone_state(page_zone(page), item);
239 EXPORT_SYMBOL(__inc_zone_page_state);
241 void __dec_zone_state(struct zone *zone, enum zone_stat_item item)
243 struct per_cpu_pageset *pcp = this_cpu_ptr(zone->pageset);
244 s8 *p = pcp->vm_stat_diff + item;
246 (*p)--;
248 if (unlikely(*p < - pcp->stat_threshold)) {
249 int overstep = pcp->stat_threshold / 2;
251 zone_page_state_add(*p - overstep, zone, item);
252 *p = overstep;
256 void __dec_zone_page_state(struct page *page, enum zone_stat_item item)
258 __dec_zone_state(page_zone(page), item);
260 EXPORT_SYMBOL(__dec_zone_page_state);
262 void inc_zone_state(struct zone *zone, enum zone_stat_item item)
264 unsigned long flags;
266 local_irq_save(flags);
267 __inc_zone_state(zone, item);
268 local_irq_restore(flags);
271 void inc_zone_page_state(struct page *page, enum zone_stat_item item)
273 unsigned long flags;
274 struct zone *zone;
276 zone = page_zone(page);
277 local_irq_save(flags);
278 __inc_zone_state(zone, item);
279 local_irq_restore(flags);
281 EXPORT_SYMBOL(inc_zone_page_state);
283 void dec_zone_page_state(struct page *page, enum zone_stat_item item)
285 unsigned long flags;
287 local_irq_save(flags);
288 __dec_zone_page_state(page, item);
289 local_irq_restore(flags);
291 EXPORT_SYMBOL(dec_zone_page_state);
294 * Update the zone counters for one cpu.
296 * The cpu specified must be either the current cpu or a processor that
297 * is not online. If it is the current cpu then the execution thread must
298 * be pinned to the current cpu.
300 * Note that refresh_cpu_vm_stats strives to only access
301 * node local memory. The per cpu pagesets on remote zones are placed
302 * in the memory local to the processor using that pageset. So the
303 * loop over all zones will access a series of cachelines local to
304 * the processor.
306 * The call to zone_page_state_add updates the cachelines with the
307 * statistics in the remote zone struct as well as the global cachelines
308 * with the global counters. These could cause remote node cache line
309 * bouncing and will have to be only done when necessary.
311 void refresh_cpu_vm_stats(int cpu)
313 struct zone *zone;
314 int i;
315 int global_diff[NR_VM_ZONE_STAT_ITEMS] = { 0, };
317 for_each_populated_zone(zone) {
318 struct per_cpu_pageset *p;
320 p = per_cpu_ptr(zone->pageset, cpu);
322 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
323 if (p->vm_stat_diff[i]) {
324 unsigned long flags;
325 int v;
327 local_irq_save(flags);
328 v = p->vm_stat_diff[i];
329 p->vm_stat_diff[i] = 0;
330 local_irq_restore(flags);
331 atomic_long_add(v, &zone->vm_stat[i]);
332 global_diff[i] += v;
333 #ifdef CONFIG_NUMA
334 /* 3 seconds idle till flush */
335 p->expire = 3;
336 #endif
338 cond_resched();
339 #ifdef CONFIG_NUMA
341 * Deal with draining the remote pageset of this
342 * processor
344 * Check if there are pages remaining in this pageset
345 * if not then there is nothing to expire.
347 if (!p->expire || !p->pcp.count)
348 continue;
351 * We never drain zones local to this processor.
353 if (zone_to_nid(zone) == numa_node_id()) {
354 p->expire = 0;
355 continue;
358 p->expire--;
359 if (p->expire)
360 continue;
362 if (p->pcp.count)
363 drain_zone_pages(zone, &p->pcp);
364 #endif
367 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
368 if (global_diff[i])
369 atomic_long_add(global_diff[i], &vm_stat[i]);
372 #endif
374 #ifdef CONFIG_NUMA
376 * zonelist = the list of zones passed to the allocator
377 * z = the zone from which the allocation occurred.
379 * Must be called with interrupts disabled.
381 void zone_statistics(struct zone *preferred_zone, struct zone *z)
383 if (z->zone_pgdat == preferred_zone->zone_pgdat) {
384 __inc_zone_state(z, NUMA_HIT);
385 } else {
386 __inc_zone_state(z, NUMA_MISS);
387 __inc_zone_state(preferred_zone, NUMA_FOREIGN);
389 if (z->node == numa_node_id())
390 __inc_zone_state(z, NUMA_LOCAL);
391 else
392 __inc_zone_state(z, NUMA_OTHER);
394 #endif
396 #ifdef CONFIG_COMPACTION
397 struct contig_page_info {
398 unsigned long free_pages;
399 unsigned long free_blocks_total;
400 unsigned long free_blocks_suitable;
404 * Calculate the number of free pages in a zone, how many contiguous
405 * pages are free and how many are large enough to satisfy an allocation of
406 * the target size. Note that this function makes no attempt to estimate
407 * how many suitable free blocks there *might* be if MOVABLE pages were
408 * migrated. Calculating that is possible, but expensive and can be
409 * figured out from userspace
411 static void fill_contig_page_info(struct zone *zone,
412 unsigned int suitable_order,
413 struct contig_page_info *info)
415 unsigned int order;
417 info->free_pages = 0;
418 info->free_blocks_total = 0;
419 info->free_blocks_suitable = 0;
421 for (order = 0; order < MAX_ORDER; order++) {
422 unsigned long blocks;
424 /* Count number of free blocks */
425 blocks = zone->free_area[order].nr_free;
426 info->free_blocks_total += blocks;
428 /* Count free base pages */
429 info->free_pages += blocks << order;
431 /* Count the suitable free blocks */
432 if (order >= suitable_order)
433 info->free_blocks_suitable += blocks <<
434 (order - suitable_order);
439 * A fragmentation index only makes sense if an allocation of a requested
440 * size would fail. If that is true, the fragmentation index indicates
441 * whether external fragmentation or a lack of memory was the problem.
442 * The value can be used to determine if page reclaim or compaction
443 * should be used
445 static int __fragmentation_index(unsigned int order, struct contig_page_info *info)
447 unsigned long requested = 1UL << order;
449 if (!info->free_blocks_total)
450 return 0;
452 /* Fragmentation index only makes sense when a request would fail */
453 if (info->free_blocks_suitable)
454 return -1000;
457 * Index is between 0 and 1 so return within 3 decimal places
459 * 0 => allocation would fail due to lack of memory
460 * 1 => allocation would fail due to fragmentation
462 return 1000 - div_u64( (1000+(div_u64(info->free_pages * 1000ULL, requested))), info->free_blocks_total);
465 /* Same as __fragmentation index but allocs contig_page_info on stack */
466 int fragmentation_index(struct zone *zone, unsigned int order)
468 struct contig_page_info info;
470 fill_contig_page_info(zone, order, &info);
471 return __fragmentation_index(order, &info);
473 #endif
475 #if defined(CONFIG_PROC_FS) || defined(CONFIG_COMPACTION)
476 #include <linux/proc_fs.h>
477 #include <linux/seq_file.h>
479 static char * const migratetype_names[MIGRATE_TYPES] = {
480 "Unmovable",
481 "Reclaimable",
482 "Movable",
483 "Reserve",
484 "Isolate",
487 static void *frag_start(struct seq_file *m, loff_t *pos)
489 pg_data_t *pgdat;
490 loff_t node = *pos;
491 for (pgdat = first_online_pgdat();
492 pgdat && node;
493 pgdat = next_online_pgdat(pgdat))
494 --node;
496 return pgdat;
499 static void *frag_next(struct seq_file *m, void *arg, loff_t *pos)
501 pg_data_t *pgdat = (pg_data_t *)arg;
503 (*pos)++;
504 return next_online_pgdat(pgdat);
507 static void frag_stop(struct seq_file *m, void *arg)
511 /* Walk all the zones in a node and print using a callback */
512 static void walk_zones_in_node(struct seq_file *m, pg_data_t *pgdat,
513 void (*print)(struct seq_file *m, pg_data_t *, struct zone *))
515 struct zone *zone;
516 struct zone *node_zones = pgdat->node_zones;
517 unsigned long flags;
519 for (zone = node_zones; zone - node_zones < MAX_NR_ZONES; ++zone) {
520 if (!populated_zone(zone))
521 continue;
523 spin_lock_irqsave(&zone->lock, flags);
524 print(m, pgdat, zone);
525 spin_unlock_irqrestore(&zone->lock, flags);
528 #endif
530 #ifdef CONFIG_PROC_FS
531 static void frag_show_print(struct seq_file *m, pg_data_t *pgdat,
532 struct zone *zone)
534 int order;
536 seq_printf(m, "Node %d, zone %8s ", pgdat->node_id, zone->name);
537 for (order = 0; order < MAX_ORDER; ++order)
538 seq_printf(m, "%6lu ", zone->free_area[order].nr_free);
539 seq_putc(m, '\n');
543 * This walks the free areas for each zone.
545 static int frag_show(struct seq_file *m, void *arg)
547 pg_data_t *pgdat = (pg_data_t *)arg;
548 walk_zones_in_node(m, pgdat, frag_show_print);
549 return 0;
552 static void pagetypeinfo_showfree_print(struct seq_file *m,
553 pg_data_t *pgdat, struct zone *zone)
555 int order, mtype;
557 for (mtype = 0; mtype < MIGRATE_TYPES; mtype++) {
558 seq_printf(m, "Node %4d, zone %8s, type %12s ",
559 pgdat->node_id,
560 zone->name,
561 migratetype_names[mtype]);
562 for (order = 0; order < MAX_ORDER; ++order) {
563 unsigned long freecount = 0;
564 struct free_area *area;
565 struct list_head *curr;
567 area = &(zone->free_area[order]);
569 list_for_each(curr, &area->free_list[mtype])
570 freecount++;
571 seq_printf(m, "%6lu ", freecount);
573 seq_putc(m, '\n');
577 /* Print out the free pages at each order for each migatetype */
578 static int pagetypeinfo_showfree(struct seq_file *m, void *arg)
580 int order;
581 pg_data_t *pgdat = (pg_data_t *)arg;
583 /* Print header */
584 seq_printf(m, "%-43s ", "Free pages count per migrate type at order");
585 for (order = 0; order < MAX_ORDER; ++order)
586 seq_printf(m, "%6d ", order);
587 seq_putc(m, '\n');
589 walk_zones_in_node(m, pgdat, pagetypeinfo_showfree_print);
591 return 0;
594 static void pagetypeinfo_showblockcount_print(struct seq_file *m,
595 pg_data_t *pgdat, struct zone *zone)
597 int mtype;
598 unsigned long pfn;
599 unsigned long start_pfn = zone->zone_start_pfn;
600 unsigned long end_pfn = start_pfn + zone->spanned_pages;
601 unsigned long count[MIGRATE_TYPES] = { 0, };
603 for (pfn = start_pfn; pfn < end_pfn; pfn += pageblock_nr_pages) {
604 struct page *page;
606 if (!pfn_valid(pfn))
607 continue;
609 page = pfn_to_page(pfn);
611 /* Watch for unexpected holes punched in the memmap */
612 if (!memmap_valid_within(pfn, page, zone))
613 continue;
615 mtype = get_pageblock_migratetype(page);
617 if (mtype < MIGRATE_TYPES)
618 count[mtype]++;
621 /* Print counts */
622 seq_printf(m, "Node %d, zone %8s ", pgdat->node_id, zone->name);
623 for (mtype = 0; mtype < MIGRATE_TYPES; mtype++)
624 seq_printf(m, "%12lu ", count[mtype]);
625 seq_putc(m, '\n');
628 /* Print out the free pages at each order for each migratetype */
629 static int pagetypeinfo_showblockcount(struct seq_file *m, void *arg)
631 int mtype;
632 pg_data_t *pgdat = (pg_data_t *)arg;
634 seq_printf(m, "\n%-23s", "Number of blocks type ");
635 for (mtype = 0; mtype < MIGRATE_TYPES; mtype++)
636 seq_printf(m, "%12s ", migratetype_names[mtype]);
637 seq_putc(m, '\n');
638 walk_zones_in_node(m, pgdat, pagetypeinfo_showblockcount_print);
640 return 0;
644 * This prints out statistics in relation to grouping pages by mobility.
645 * It is expensive to collect so do not constantly read the file.
647 static int pagetypeinfo_show(struct seq_file *m, void *arg)
649 pg_data_t *pgdat = (pg_data_t *)arg;
651 /* check memoryless node */
652 if (!node_state(pgdat->node_id, N_HIGH_MEMORY))
653 return 0;
655 seq_printf(m, "Page block order: %d\n", pageblock_order);
656 seq_printf(m, "Pages per block: %lu\n", pageblock_nr_pages);
657 seq_putc(m, '\n');
658 pagetypeinfo_showfree(m, pgdat);
659 pagetypeinfo_showblockcount(m, pgdat);
661 return 0;
664 static const struct seq_operations fragmentation_op = {
665 .start = frag_start,
666 .next = frag_next,
667 .stop = frag_stop,
668 .show = frag_show,
671 static int fragmentation_open(struct inode *inode, struct file *file)
673 return seq_open(file, &fragmentation_op);
676 static const struct file_operations fragmentation_file_operations = {
677 .open = fragmentation_open,
678 .read = seq_read,
679 .llseek = seq_lseek,
680 .release = seq_release,
683 static const struct seq_operations pagetypeinfo_op = {
684 .start = frag_start,
685 .next = frag_next,
686 .stop = frag_stop,
687 .show = pagetypeinfo_show,
690 static int pagetypeinfo_open(struct inode *inode, struct file *file)
692 return seq_open(file, &pagetypeinfo_op);
695 static const struct file_operations pagetypeinfo_file_ops = {
696 .open = pagetypeinfo_open,
697 .read = seq_read,
698 .llseek = seq_lseek,
699 .release = seq_release,
702 #ifdef CONFIG_ZONE_DMA
703 #define TEXT_FOR_DMA(xx) xx "_dma",
704 #else
705 #define TEXT_FOR_DMA(xx)
706 #endif
708 #ifdef CONFIG_ZONE_DMA32
709 #define TEXT_FOR_DMA32(xx) xx "_dma32",
710 #else
711 #define TEXT_FOR_DMA32(xx)
712 #endif
714 #ifdef CONFIG_HIGHMEM
715 #define TEXT_FOR_HIGHMEM(xx) xx "_high",
716 #else
717 #define TEXT_FOR_HIGHMEM(xx)
718 #endif
720 #define TEXTS_FOR_ZONES(xx) TEXT_FOR_DMA(xx) TEXT_FOR_DMA32(xx) xx "_normal", \
721 TEXT_FOR_HIGHMEM(xx) xx "_movable",
723 static const char * const vmstat_text[] = {
724 /* Zoned VM counters */
725 "nr_free_pages",
726 "nr_inactive_anon",
727 "nr_active_anon",
728 "nr_inactive_file",
729 "nr_active_file",
730 "nr_unevictable",
731 "nr_mlock",
732 "nr_anon_pages",
733 "nr_mapped",
734 "nr_file_pages",
735 "nr_dirty",
736 "nr_writeback",
737 "nr_slab_reclaimable",
738 "nr_slab_unreclaimable",
739 "nr_page_table_pages",
740 "nr_kernel_stack",
741 "nr_unstable",
742 "nr_bounce",
743 "nr_vmscan_write",
744 "nr_writeback_temp",
745 "nr_isolated_anon",
746 "nr_isolated_file",
747 "nr_shmem",
748 #ifdef CONFIG_NUMA
749 "numa_hit",
750 "numa_miss",
751 "numa_foreign",
752 "numa_interleave",
753 "numa_local",
754 "numa_other",
755 #endif
757 #ifdef CONFIG_VM_EVENT_COUNTERS
758 "pgpgin",
759 "pgpgout",
760 "pswpin",
761 "pswpout",
763 TEXTS_FOR_ZONES("pgalloc")
765 "pgfree",
766 "pgactivate",
767 "pgdeactivate",
769 "pgfault",
770 "pgmajfault",
772 TEXTS_FOR_ZONES("pgrefill")
773 TEXTS_FOR_ZONES("pgsteal")
774 TEXTS_FOR_ZONES("pgscan_kswapd")
775 TEXTS_FOR_ZONES("pgscan_direct")
777 #ifdef CONFIG_NUMA
778 "zone_reclaim_failed",
779 #endif
780 "pginodesteal",
781 "slabs_scanned",
782 "kswapd_steal",
783 "kswapd_inodesteal",
784 "kswapd_low_wmark_hit_quickly",
785 "kswapd_high_wmark_hit_quickly",
786 "kswapd_skip_congestion_wait",
787 "pageoutrun",
788 "allocstall",
790 "pgrotated",
792 #ifdef CONFIG_COMPACTION
793 "compact_blocks_moved",
794 "compact_pages_moved",
795 "compact_pagemigrate_failed",
796 "compact_stall",
797 "compact_fail",
798 "compact_success",
799 #endif
801 #ifdef CONFIG_HUGETLB_PAGE
802 "htlb_buddy_alloc_success",
803 "htlb_buddy_alloc_fail",
804 #endif
805 "unevictable_pgs_culled",
806 "unevictable_pgs_scanned",
807 "unevictable_pgs_rescued",
808 "unevictable_pgs_mlocked",
809 "unevictable_pgs_munlocked",
810 "unevictable_pgs_cleared",
811 "unevictable_pgs_stranded",
812 "unevictable_pgs_mlockfreed",
813 #endif
816 static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat,
817 struct zone *zone)
819 int i;
820 seq_printf(m, "Node %d, zone %8s", pgdat->node_id, zone->name);
821 seq_printf(m,
822 "\n pages free %lu"
823 "\n min %lu"
824 "\n low %lu"
825 "\n high %lu"
826 "\n scanned %lu"
827 "\n spanned %lu"
828 "\n present %lu",
829 zone_nr_free_pages(zone),
830 min_wmark_pages(zone),
831 low_wmark_pages(zone),
832 high_wmark_pages(zone),
833 zone->pages_scanned,
834 zone->spanned_pages,
835 zone->present_pages);
837 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
838 seq_printf(m, "\n %-12s %lu", vmstat_text[i],
839 zone_page_state(zone, i));
841 seq_printf(m,
842 "\n protection: (%lu",
843 zone->lowmem_reserve[0]);
844 for (i = 1; i < ARRAY_SIZE(zone->lowmem_reserve); i++)
845 seq_printf(m, ", %lu", zone->lowmem_reserve[i]);
846 seq_printf(m,
848 "\n pagesets");
849 for_each_online_cpu(i) {
850 struct per_cpu_pageset *pageset;
852 pageset = per_cpu_ptr(zone->pageset, i);
853 seq_printf(m,
854 "\n cpu: %i"
855 "\n count: %i"
856 "\n high: %i"
857 "\n batch: %i",
859 pageset->pcp.count,
860 pageset->pcp.high,
861 pageset->pcp.batch);
862 #ifdef CONFIG_SMP
863 seq_printf(m, "\n vm stats threshold: %d",
864 pageset->stat_threshold);
865 #endif
867 seq_printf(m,
868 "\n all_unreclaimable: %u"
869 "\n start_pfn: %lu"
870 "\n inactive_ratio: %u",
871 zone->all_unreclaimable,
872 zone->zone_start_pfn,
873 zone->inactive_ratio);
874 seq_putc(m, '\n');
878 * Output information about zones in @pgdat.
880 static int zoneinfo_show(struct seq_file *m, void *arg)
882 pg_data_t *pgdat = (pg_data_t *)arg;
883 walk_zones_in_node(m, pgdat, zoneinfo_show_print);
884 return 0;
887 static const struct seq_operations zoneinfo_op = {
888 .start = frag_start, /* iterate over all zones. The same as in
889 * fragmentation. */
890 .next = frag_next,
891 .stop = frag_stop,
892 .show = zoneinfo_show,
895 static int zoneinfo_open(struct inode *inode, struct file *file)
897 return seq_open(file, &zoneinfo_op);
900 static const struct file_operations proc_zoneinfo_file_operations = {
901 .open = zoneinfo_open,
902 .read = seq_read,
903 .llseek = seq_lseek,
904 .release = seq_release,
907 static void *vmstat_start(struct seq_file *m, loff_t *pos)
909 unsigned long *v;
910 #ifdef CONFIG_VM_EVENT_COUNTERS
911 unsigned long *e;
912 #endif
913 int i;
915 if (*pos >= ARRAY_SIZE(vmstat_text))
916 return NULL;
918 #ifdef CONFIG_VM_EVENT_COUNTERS
919 v = kmalloc(NR_VM_ZONE_STAT_ITEMS * sizeof(unsigned long)
920 + sizeof(struct vm_event_state), GFP_KERNEL);
921 #else
922 v = kmalloc(NR_VM_ZONE_STAT_ITEMS * sizeof(unsigned long),
923 GFP_KERNEL);
924 #endif
925 m->private = v;
926 if (!v)
927 return ERR_PTR(-ENOMEM);
928 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
929 v[i] = global_page_state(i);
930 #ifdef CONFIG_VM_EVENT_COUNTERS
931 e = v + NR_VM_ZONE_STAT_ITEMS;
932 all_vm_events(e);
933 e[PGPGIN] /= 2; /* sectors -> kbytes */
934 e[PGPGOUT] /= 2;
935 #endif
936 return v + *pos;
939 static void *vmstat_next(struct seq_file *m, void *arg, loff_t *pos)
941 (*pos)++;
942 if (*pos >= ARRAY_SIZE(vmstat_text))
943 return NULL;
944 return (unsigned long *)m->private + *pos;
947 static int vmstat_show(struct seq_file *m, void *arg)
949 unsigned long *l = arg;
950 unsigned long off = l - (unsigned long *)m->private;
952 seq_printf(m, "%s %lu\n", vmstat_text[off], *l);
953 return 0;
956 static void vmstat_stop(struct seq_file *m, void *arg)
958 kfree(m->private);
959 m->private = NULL;
962 static const struct seq_operations vmstat_op = {
963 .start = vmstat_start,
964 .next = vmstat_next,
965 .stop = vmstat_stop,
966 .show = vmstat_show,
969 static int vmstat_open(struct inode *inode, struct file *file)
971 return seq_open(file, &vmstat_op);
974 static const struct file_operations proc_vmstat_file_operations = {
975 .open = vmstat_open,
976 .read = seq_read,
977 .llseek = seq_lseek,
978 .release = seq_release,
980 #endif /* CONFIG_PROC_FS */
982 #ifdef CONFIG_SMP
983 static DEFINE_PER_CPU(struct delayed_work, vmstat_work);
984 int sysctl_stat_interval __read_mostly = HZ;
986 static void vmstat_update(struct work_struct *w)
988 refresh_cpu_vm_stats(smp_processor_id());
989 schedule_delayed_work(&__get_cpu_var(vmstat_work),
990 round_jiffies_relative(sysctl_stat_interval));
993 static void __cpuinit start_cpu_timer(int cpu)
995 struct delayed_work *work = &per_cpu(vmstat_work, cpu);
997 INIT_DELAYED_WORK_DEFERRABLE(work, vmstat_update);
998 schedule_delayed_work_on(cpu, work, __round_jiffies_relative(HZ, cpu));
1002 * Use the cpu notifier to insure that the thresholds are recalculated
1003 * when necessary.
1005 static int __cpuinit vmstat_cpuup_callback(struct notifier_block *nfb,
1006 unsigned long action,
1007 void *hcpu)
1009 long cpu = (long)hcpu;
1011 switch (action) {
1012 case CPU_ONLINE:
1013 case CPU_ONLINE_FROZEN:
1014 refresh_zone_stat_thresholds();
1015 start_cpu_timer(cpu);
1016 node_set_state(cpu_to_node(cpu), N_CPU);
1017 break;
1018 case CPU_DOWN_PREPARE:
1019 case CPU_DOWN_PREPARE_FROZEN:
1020 cancel_rearming_delayed_work(&per_cpu(vmstat_work, cpu));
1021 per_cpu(vmstat_work, cpu).work.func = NULL;
1022 break;
1023 case CPU_DOWN_FAILED:
1024 case CPU_DOWN_FAILED_FROZEN:
1025 start_cpu_timer(cpu);
1026 break;
1027 case CPU_DEAD:
1028 case CPU_DEAD_FROZEN:
1029 refresh_zone_stat_thresholds();
1030 break;
1031 default:
1032 break;
1034 return NOTIFY_OK;
1037 static struct notifier_block __cpuinitdata vmstat_notifier =
1038 { &vmstat_cpuup_callback, NULL, 0 };
1039 #endif
1041 static int __init setup_vmstat(void)
1043 #ifdef CONFIG_SMP
1044 int cpu;
1046 refresh_zone_stat_thresholds();
1047 register_cpu_notifier(&vmstat_notifier);
1049 for_each_online_cpu(cpu)
1050 start_cpu_timer(cpu);
1051 #endif
1052 #ifdef CONFIG_PROC_FS
1053 proc_create("buddyinfo", S_IRUGO, NULL, &fragmentation_file_operations);
1054 proc_create("pagetypeinfo", S_IRUGO, NULL, &pagetypeinfo_file_ops);
1055 proc_create("vmstat", S_IRUGO, NULL, &proc_vmstat_file_operations);
1056 proc_create("zoneinfo", S_IRUGO, NULL, &proc_zoneinfo_file_operations);
1057 #endif
1058 return 0;
1060 module_init(setup_vmstat)
1062 #if defined(CONFIG_DEBUG_FS) && defined(CONFIG_COMPACTION)
1063 #include <linux/debugfs.h>
1065 static struct dentry *extfrag_debug_root;
1068 * Return an index indicating how much of the available free memory is
1069 * unusable for an allocation of the requested size.
1071 static int unusable_free_index(unsigned int order,
1072 struct contig_page_info *info)
1074 /* No free memory is interpreted as all free memory is unusable */
1075 if (info->free_pages == 0)
1076 return 1000;
1079 * Index should be a value between 0 and 1. Return a value to 3
1080 * decimal places.
1082 * 0 => no fragmentation
1083 * 1 => high fragmentation
1085 return div_u64((info->free_pages - (info->free_blocks_suitable << order)) * 1000ULL, info->free_pages);
1089 static void unusable_show_print(struct seq_file *m,
1090 pg_data_t *pgdat, struct zone *zone)
1092 unsigned int order;
1093 int index;
1094 struct contig_page_info info;
1096 seq_printf(m, "Node %d, zone %8s ",
1097 pgdat->node_id,
1098 zone->name);
1099 for (order = 0; order < MAX_ORDER; ++order) {
1100 fill_contig_page_info(zone, order, &info);
1101 index = unusable_free_index(order, &info);
1102 seq_printf(m, "%d.%03d ", index / 1000, index % 1000);
1105 seq_putc(m, '\n');
1109 * Display unusable free space index
1111 * The unusable free space index measures how much of the available free
1112 * memory cannot be used to satisfy an allocation of a given size and is a
1113 * value between 0 and 1. The higher the value, the more of free memory is
1114 * unusable and by implication, the worse the external fragmentation is. This
1115 * can be expressed as a percentage by multiplying by 100.
1117 static int unusable_show(struct seq_file *m, void *arg)
1119 pg_data_t *pgdat = (pg_data_t *)arg;
1121 /* check memoryless node */
1122 if (!node_state(pgdat->node_id, N_HIGH_MEMORY))
1123 return 0;
1125 walk_zones_in_node(m, pgdat, unusable_show_print);
1127 return 0;
1130 static const struct seq_operations unusable_op = {
1131 .start = frag_start,
1132 .next = frag_next,
1133 .stop = frag_stop,
1134 .show = unusable_show,
1137 static int unusable_open(struct inode *inode, struct file *file)
1139 return seq_open(file, &unusable_op);
1142 static const struct file_operations unusable_file_ops = {
1143 .open = unusable_open,
1144 .read = seq_read,
1145 .llseek = seq_lseek,
1146 .release = seq_release,
1149 static void extfrag_show_print(struct seq_file *m,
1150 pg_data_t *pgdat, struct zone *zone)
1152 unsigned int order;
1153 int index;
1155 /* Alloc on stack as interrupts are disabled for zone walk */
1156 struct contig_page_info info;
1158 seq_printf(m, "Node %d, zone %8s ",
1159 pgdat->node_id,
1160 zone->name);
1161 for (order = 0; order < MAX_ORDER; ++order) {
1162 fill_contig_page_info(zone, order, &info);
1163 index = __fragmentation_index(order, &info);
1164 seq_printf(m, "%d.%03d ", index / 1000, index % 1000);
1167 seq_putc(m, '\n');
1171 * Display fragmentation index for orders that allocations would fail for
1173 static int extfrag_show(struct seq_file *m, void *arg)
1175 pg_data_t *pgdat = (pg_data_t *)arg;
1177 walk_zones_in_node(m, pgdat, extfrag_show_print);
1179 return 0;
1182 static const struct seq_operations extfrag_op = {
1183 .start = frag_start,
1184 .next = frag_next,
1185 .stop = frag_stop,
1186 .show = extfrag_show,
1189 static int extfrag_open(struct inode *inode, struct file *file)
1191 return seq_open(file, &extfrag_op);
1194 static const struct file_operations extfrag_file_ops = {
1195 .open = extfrag_open,
1196 .read = seq_read,
1197 .llseek = seq_lseek,
1198 .release = seq_release,
1201 static int __init extfrag_debug_init(void)
1203 extfrag_debug_root = debugfs_create_dir("extfrag", NULL);
1204 if (!extfrag_debug_root)
1205 return -ENOMEM;
1207 if (!debugfs_create_file("unusable_index", 0444,
1208 extfrag_debug_root, NULL, &unusable_file_ops))
1209 return -ENOMEM;
1211 if (!debugfs_create_file("extfrag_index", 0444,
1212 extfrag_debug_root, NULL, &extfrag_file_ops))
1213 return -ENOMEM;
1215 return 0;
1218 module_init(extfrag_debug_init);
1219 #endif