| /* |
| * linux/mm/vmstat.c |
| * |
| * Manages VM statistics |
| * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds |
| * |
| * zoned VM statistics |
| * Copyright (C) 2006 Silicon Graphics, Inc., |
| * Christoph Lameter <christoph@lameter.com> |
| */ |
| |
| #include <linux/config.h> |
| #include <linux/mm.h> |
| #include <linux/module.h> |
| #include <linux/cpu.h> |
| |
| 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; |
| } |
| } |
| |
| #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); |
| } |
| EXPORT_SYMBOL_GPL(all_vm_events); |
| |
| #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 */ |
| |
| /* |
| * 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 |
| |
| static int calculate_threshold(struct zone *zone) |
| { |
| int threshold; |
| int mem; /* memory in 128 MB units */ |
| |
| /* |
| * The threshold scales with the number of processors and the amount |
| * of memory per zone. More memory means that we can defer updates for |
| * longer, more processors could lead to more contention. |
| * fls() is used to have a cheap way of logarithmic scaling. |
| * |
| * Some sample thresholds: |
| * |
| * Threshold Processors (fls) Zonesize fls(mem+1) |
| * ------------------------------------------------------------------ |
| * 8 1 1 0.9-1 GB 4 |
| * 16 2 2 0.9-1 GB 4 |
| * 20 2 2 1-2 GB 5 |
| * 24 2 2 2-4 GB 6 |
| * 28 2 2 4-8 GB 7 |
| * 32 2 2 8-16 GB 8 |
| * 4 2 2 <128M 1 |
| * 30 4 3 2-4 GB 5 |
| * 48 4 3 8-16 GB 8 |
| * 32 8 4 1-2 GB 4 |
| * 32 8 4 0.9-1GB 4 |
| * 10 16 5 <128M 1 |
| * 40 16 5 900M 4 |
| * 70 64 7 2-4 GB 5 |
| * 84 64 7 4-8 GB 6 |
| * 108 512 9 4-8 GB 6 |
| * 125 1024 10 8-16 GB 8 |
| * 125 1024 10 16-32 GB 9 |
| */ |
| |
| mem = zone->present_pages >> (27 - PAGE_SHIFT); |
| |
| threshold = 2 * fls(num_online_cpus()) * (1 + fls(mem)); |
| |
| /* |
| * Maximum threshold is 125 |
| */ |
| threshold = min(125, threshold); |
| |
| return threshold; |
| } |
| |
| /* |
| * Refresh the thresholds for each zone. |
| */ |
| static void refresh_zone_stat_thresholds(void) |
| { |
| struct zone *zone; |
| int cpu; |
| int threshold; |
| |
| for_each_zone(zone) { |
| |
| if (!zone->present_pages) |
| continue; |
| |
| threshold = calculate_threshold(zone); |
| |
| for_each_online_cpu(cpu) |
| zone_pcp(zone, cpu)->stat_threshold = threshold; |
| } |
| } |
| |
| /* |
| * For use when we know that interrupts are disabled. |
| */ |
| void __mod_zone_page_state(struct zone *zone, enum zone_stat_item item, |
| int delta) |
| { |
| struct per_cpu_pageset *pcp = zone_pcp(zone, smp_processor_id()); |
| s8 *p = pcp->vm_stat_diff + item; |
| long x; |
| |
| x = delta + *p; |
| |
| if (unlikely(x > pcp->stat_threshold || x < -pcp->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. |
| * |
| * NOTE: These functions are very performance sensitive. Change only |
| * with care. |
| * |
| * 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. |
| */ |
| static void __inc_zone_state(struct zone *zone, enum zone_stat_item item) |
| { |
| struct per_cpu_pageset *pcp = zone_pcp(zone, smp_processor_id()); |
| s8 *p = pcp->vm_stat_diff + item; |
| |
| (*p)++; |
| |
| if (unlikely(*p > pcp->stat_threshold)) { |
| int overstep = pcp->stat_threshold / 2; |
| |
| zone_page_state_add(*p + overstep, zone, item); |
| *p = -overstep; |
| } |
| } |
| |
| void __inc_zone_page_state(struct page *page, enum zone_stat_item item) |
| { |
| __inc_zone_state(page_zone(page), item); |
| } |
| 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); |
| struct per_cpu_pageset *pcp = zone_pcp(zone, smp_processor_id()); |
| s8 *p = pcp->vm_stat_diff + item; |
| |
| (*p)--; |
| |
| if (unlikely(*p < - pcp->stat_threshold)) { |
| int overstep = pcp->stat_threshold / 2; |
| |
| zone_page_state_add(*p - overstep, zone, item); |
| *p = overstep; |
| } |
| } |
| EXPORT_SYMBOL(__dec_zone_page_state); |
| |
| 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); |
| } |
| |
| 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); |
| __inc_zone_state(zone, item); |
| 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; |
| |
| local_irq_save(flags); |
| __dec_zone_page_state(page, item); |
| 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; |
| |
| if (!populated_zone(zone)) |
| continue; |
| |
| 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 |
| |
| #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 |
| |
| #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, |
| }; |
| |
| #ifdef CONFIG_ZONE_DMA32 |
| #define TEXT_FOR_DMA32(xx) xx "_dma32", |
| #else |
| #define TEXT_FOR_DMA32(xx) |
| #endif |
| |
| #ifdef CONFIG_HIGHMEM |
| #define TEXT_FOR_HIGHMEM(xx) xx "_high", |
| #else |
| #define TEXT_FOR_HIGHMEM(xx) |
| #endif |
| |
| #define TEXTS_FOR_ZONES(xx) xx "_dma", TEXT_FOR_DMA32(xx) xx "_normal", \ |
| TEXT_FOR_HIGHMEM(xx) |
| |
| static char *vmstat_text[] = { |
| /* Zoned VM counters */ |
| "nr_anon_pages", |
| "nr_mapped", |
| "nr_file_pages", |
| "nr_slab_reclaimable", |
| "nr_slab_unreclaimable", |
| "nr_page_table_pages", |
| "nr_dirty", |
| "nr_writeback", |
| "nr_unstable", |
| "nr_bounce", |
| "nr_vmscan_write", |
| |
| #ifdef CONFIG_NUMA |
| "numa_hit", |
| "numa_miss", |
| "numa_foreign", |
| "numa_interleave", |
| "numa_local", |
| "numa_other", |
| #endif |
| |
| #ifdef CONFIG_VM_EVENT_COUNTERS |
| "pgpgin", |
| "pgpgout", |
| "pswpin", |
| "pswpout", |
| |
| TEXTS_FOR_ZONES("pgalloc") |
| |
| "pgfree", |
| "pgactivate", |
| "pgdeactivate", |
| |
| "pgfault", |
| "pgmajfault", |
| |
| TEXTS_FOR_ZONES("pgrefill") |
| TEXTS_FOR_ZONES("pgsteal") |
| TEXTS_FOR_ZONES("pgscan_kswapd") |
| TEXTS_FOR_ZONES("pgscan_direct") |
| |
| "pginodesteal", |
| "slabs_scanned", |
| "kswapd_steal", |
| "kswapd_inodesteal", |
| "pageoutrun", |
| "allocstall", |
| |
| "pgrotated", |
| #endif |
| }; |
| |
| /* |
| * 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); |
| |
| for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) |
| seq_printf(m, "\n %-12s %lu", vmstat_text[i], |
| zone_page_state(zone, i)); |
| |
| 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); |
| } |
| #ifdef CONFIG_SMP |
| seq_printf(m, "\n vm stats threshold: %d", |
| pageset->stat_threshold); |
| #endif |
| } |
| 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) |
| { |
| unsigned long *v; |
| #ifdef CONFIG_VM_EVENT_COUNTERS |
| unsigned long *e; |
| #endif |
| int i; |
| |
| if (*pos >= ARRAY_SIZE(vmstat_text)) |
| return NULL; |
| |
| #ifdef CONFIG_VM_EVENT_COUNTERS |
| v = kmalloc(NR_VM_ZONE_STAT_ITEMS * sizeof(unsigned long) |
| + sizeof(struct vm_event_state), GFP_KERNEL); |
| #else |
| v = kmalloc(NR_VM_ZONE_STAT_ITEMS * sizeof(unsigned long), |
| GFP_KERNEL); |
| #endif |
| m->private = v; |
| if (!v) |
| return ERR_PTR(-ENOMEM); |
| for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) |
| v[i] = global_page_state(i); |
| #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 |
| return v + *pos; |
| } |
| |
| 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 */ |
| |
| #ifdef CONFIG_SMP |
| /* |
| * Use the cpu notifier to insure that the thresholds are recalculated |
| * when necessary. |
| */ |
| static int __cpuinit vmstat_cpuup_callback(struct notifier_block *nfb, |
| unsigned long action, |
| void *hcpu) |
| { |
| switch (action) { |
| case CPU_UP_PREPARE: |
| case CPU_UP_CANCELED: |
| case CPU_DEAD: |
| refresh_zone_stat_thresholds(); |
| break; |
| default: |
| break; |
| } |
| return NOTIFY_OK; |
| } |
| |
| static struct notifier_block __cpuinitdata vmstat_notifier = |
| { &vmstat_cpuup_callback, NULL, 0 }; |
| |
| int __init setup_vmstat(void) |
| { |
| refresh_zone_stat_thresholds(); |
| register_cpu_notifier(&vmstat_notifier); |
| return 0; |
| } |
| module_init(setup_vmstat) |
| #endif |