1 files changed, 706 insertions, 0 deletions

diff --git a/mm/vmstat.c b/mm/vmstat.c
new file mode 100644
index 000000000000..a2b6a9f96e5c
--- /dev/null
+++ b/mm/vmstat.c
@@ -0,0 +1,706 @@
+/*
+ *  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->node == 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