--- /dev/null
+/*
+ * 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/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;
+
+ 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,
+};
+
+static char *vmstat_text[] = {
+ /* Zoned VM counters */
+ "nr_anon_pages",
+ "nr_mapped",
+ "nr_file_pages",
+ "nr_slab",
+ "nr_page_table_pages",
+ "nr_dirty",
+ "nr_writeback",
+ "nr_unstable",
+ "nr_bounce",
+
+#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",
+
+ "pgalloc_dma",
+ "pgalloc_dma32",
+ "pgalloc_normal",
+ "pgalloc_high",
+
+ "pgfree",
+ "pgactivate",
+ "pgdeactivate",
+
+ "pgfault",
+ "pgmajfault",
+
+ "pgrefill_dma",
+ "pgrefill_dma32",
+ "pgrefill_normal",
+ "pgrefill_high",
+
+ "pgsteal_dma",
+ "pgsteal_dma32",
+ "pgsteal_normal",
+ "pgsteal_high",
+
+ "pgscan_kswapd_dma",
+ "pgscan_kswapd_dma32",
+ "pgscan_kswapd_normal",
+ "pgscan_kswapd_high",
+
+ "pgscan_direct_dma",
+ "pgscan_direct_dma32",
+ "pgscan_direct_normal",
+ "pgscan_direct_high",
+
+ "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 start_pfn: %lu",
+ zone->all_unreclaimable,
+ zone->prev_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
git://git.onelab.eu / linux-2.6.git / blobdiff