cgroups: make cftype.unregister_event() void-returning
[safe/jmp/linux-2.6] / mm / vmstat.c
index 9dc270a..7759941 100644 (file)
  *  Copyright (C) 2006 Silicon Graphics, Inc.,
  *             Christoph Lameter <christoph@lameter.com>
  */
-
-#include <linux/config.h>
+#include <linux/fs.h>
 #include <linux/mm.h>
+#include <linux/err.h>
 #include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/cpu.h>
+#include <linux/vmstat.h>
+#include <linux/sched.h>
+#include <linux/math64.h>
 
-/*
- * Accumulate the page_state information across all CPUs.
- * The result is unavoidably approximate - it can change
- * during and after execution of this function.
- */
-DEFINE_PER_CPU(struct page_state, page_states) = {0};
-
-static void __get_page_state(struct page_state *ret, int nr, cpumask_t *cpumask)
-{
-       unsigned cpu;
-
-       memset(ret, 0, nr * sizeof(unsigned long));
-       cpus_and(*cpumask, *cpumask, cpu_online_map);
-
-       for_each_cpu_mask(cpu, *cpumask) {
-               unsigned long *in;
-               unsigned long *out;
-               unsigned off;
-               unsigned next_cpu;
-
-               in = (unsigned long *)&per_cpu(page_states, cpu);
-
-               next_cpu = next_cpu(cpu, *cpumask);
-               if (likely(next_cpu < NR_CPUS))
-                       prefetch(&per_cpu(page_states, next_cpu));
-
-               out = (unsigned long *)ret;
-               for (off = 0; off < nr; off++)
-                       *out++ += *in++;
-       }
-}
-
-void get_full_page_state(struct page_state *ret)
-{
-       cpumask_t mask = CPU_MASK_ALL;
-
-       __get_page_state(ret, sizeof(*ret) / sizeof(unsigned long), &mask);
-}
+#ifdef CONFIG_VM_EVENT_COUNTERS
+DEFINE_PER_CPU(struct vm_event_state, vm_event_states) = {{0}};
+EXPORT_PER_CPU_SYMBOL(vm_event_states);
 
-unsigned long read_page_state_offset(unsigned long offset)
+static void sum_vm_events(unsigned long *ret, const struct cpumask *cpumask)
 {
-       unsigned long ret = 0;
        int cpu;
+       int i;
 
-       for_each_online_cpu(cpu) {
-               unsigned long in;
-
-               in = (unsigned long)&per_cpu(page_states, cpu) + offset;
-               ret += *((unsigned long *)in);
-       }
-       return ret;
-}
+       memset(ret, 0, NR_VM_EVENT_ITEMS * sizeof(unsigned long));
 
-void __mod_page_state_offset(unsigned long offset, unsigned long delta)
-{
-       void *ptr;
+       for_each_cpu(cpu, cpumask) {
+               struct vm_event_state *this = &per_cpu(vm_event_states, cpu);
 
-       ptr = &__get_cpu_var(page_states);
-       *(unsigned long *)(ptr + offset) += delta;
+               for (i = 0; i < NR_VM_EVENT_ITEMS; i++)
+                       ret[i] += this->event[i];
+       }
 }
-EXPORT_SYMBOL(__mod_page_state_offset);
 
-void mod_page_state_offset(unsigned long offset, unsigned long delta)
+/*
+ * 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)
 {
-       unsigned long flags;
-       void *ptr;
-
-       local_irq_save(flags);
-       ptr = &__get_cpu_var(page_states);
-       *(unsigned long *)(ptr + offset) += delta;
-       local_irq_restore(flags);
+       get_online_cpus();
+       sum_vm_events(ret, cpu_online_mask);
+       put_online_cpus();
 }
-EXPORT_SYMBOL(mod_page_state_offset);
+EXPORT_SYMBOL_GPL(all_vm_events);
 
-void __get_zone_counts(unsigned long *active, unsigned long *inactive,
-                       unsigned long *free, struct pglist_data *pgdat)
+#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 zone *zones = pgdat->node_zones;
+       struct vm_event_state *fold_state = &per_cpu(vm_event_states, cpu);
        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;
+       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 */
 
-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;
-       }
-}
+#endif /* CONFIG_VM_EVENT_COUNTERS */
 
 /*
  * Manage combined zone based / global counters
@@ -130,17 +81,69 @@ EXPORT_SYMBOL(vm_stat);
 
 #ifdef CONFIG_SMP
 
-#define STAT_THRESHOLD 32
+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;
+}
 
 /*
- * Determine pointer to currently valid differential byte given a zone and
- * the item number.
- *
- * Preemption must be off
+ * Refresh the thresholds for each zone.
  */
-static inline s8 *diff_pointer(struct zone *zone, enum zone_stat_item item)
+static void refresh_zone_stat_thresholds(void)
 {
-       return &zone_pcp(zone, smp_processor_id())->vm_stat_diff[item];
+       struct zone *zone;
+       int cpu;
+       int threshold;
+
+       for_each_populated_zone(zone) {
+               threshold = calculate_threshold(zone);
+
+               for_each_online_cpu(cpu)
+                       per_cpu_ptr(zone->pageset, cpu)->stat_threshold
+                                                       = threshold;
+       }
 }
 
 /*
@@ -149,17 +152,17 @@ static inline s8 *diff_pointer(struct zone *zone, enum zone_stat_item item)
 void __mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
                                int delta)
 {
-       s8 *p;
+       struct per_cpu_pageset *pcp = this_cpu_ptr(zone->pageset);
+
+       s8 *p = pcp->vm_stat_diff + item;
        long x;
 
-       p = diff_pointer(zone, item);
        x = delta + *p;
 
-       if (unlikely(x > STAT_THRESHOLD || x < -STAT_THRESHOLD)) {
+       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);
@@ -188,10 +191,12 @@ EXPORT_SYMBOL(mod_zone_page_state);
  * 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
@@ -199,50 +204,65 @@ EXPORT_SYMBOL(mod_zone_page_state);
  * in between and therefore the atomicity vs. interrupt cannot be exploited
  * in a useful way here.
  */
-void __inc_zone_page_state(struct page *page, enum zone_stat_item item)
+void __inc_zone_state(struct zone *zone, enum zone_stat_item item)
 {
-       struct zone *zone = page_zone(page);
-       s8 *p = diff_pointer(zone, item);
+       struct per_cpu_pageset *pcp = this_cpu_ptr(zone->pageset);
+       s8 *p = pcp->vm_stat_diff + item;
 
        (*p)++;
 
-       if (unlikely(*p > STAT_THRESHOLD)) {
-               zone_page_state_add(*p, zone, item);
-               *p = 0;
+       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)
+void __dec_zone_state(struct zone *zone, enum zone_stat_item item)
 {
-       struct zone *zone = page_zone(page);
-       s8 *p = diff_pointer(zone, item);
+       struct per_cpu_pageset *pcp = this_cpu_ptr(zone->pageset);
+       s8 *p = pcp->vm_stat_diff + item;
 
        (*p)--;
 
-       if (unlikely(*p < -STAT_THRESHOLD)) {
-               zone_page_state_add(*p, zone, item);
-               *p = 0;
+       if (unlikely(*p < - pcp->stat_threshold)) {
+               int overstep = pcp->stat_threshold / 2;
+
+               zone_page_state_add(*p - overstep, zone, item);
+               *p = overstep;
        }
 }
+
+void __dec_zone_page_state(struct page *page, enum zone_stat_item item)
+{
+       __dec_zone_state(page_zone(page), item);
+}
 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;
-       s8 *p;
 
        zone = page_zone(page);
        local_irq_save(flags);
-       p = diff_pointer(zone, item);
-
-       (*p)++;
-
-       if (unlikely(*p > STAT_THRESHOLD)) {
-               zone_page_state_add(*p, zone, item);
-               *p = 0;
-       }
+       __inc_zone_state(zone, item);
        local_irq_restore(flags);
 }
 EXPORT_SYMBOL(inc_zone_page_state);
@@ -250,71 +270,207 @@ EXPORT_SYMBOL(inc_zone_page_state);
 void dec_zone_page_state(struct page *page, enum zone_stat_item item)
 {
        unsigned long flags;
-       struct zone *zone;
-       s8 *p;
 
-       zone = page_zone(page);
        local_irq_save(flags);
-       p = diff_pointer(zone, item);
-
-       (*p)--;
-
-       if (unlikely(*p < -STAT_THRESHOLD)) {
-               zone_page_state_add(*p, zone, item);
-               *p = 0;
-       }
+       __dec_zone_page_state(page, item);
        local_irq_restore(flags);
 }
 EXPORT_SYMBOL(dec_zone_page_state);
 
 /*
  * Update the zone counters for one cpu.
+ *
+ * The cpu specified must be either the current cpu or a processor that
+ * is not online. If it is the current cpu then the execution thread must
+ * be pinned to the current cpu.
+ *
+ * Note that refresh_cpu_vm_stats strives to only access
+ * node local memory. The per cpu pagesets on remote zones are placed
+ * in the memory local to the processor using that pageset. So the
+ * loop over all zones will access a series of cachelines local to
+ * the processor.
+ *
+ * The call to zone_page_state_add updates the cachelines with the
+ * statistics in the remote zone struct as well as the global cachelines
+ * with the global counters. These could cause remote node cache line
+ * bouncing and will have to be only done when necessary.
  */
 void refresh_cpu_vm_stats(int cpu)
 {
        struct zone *zone;
        int i;
-       unsigned long flags;
+       int global_diff[NR_VM_ZONE_STAT_ITEMS] = { 0, };
 
-       for_each_zone(zone) {
-               struct per_cpu_pageset *pcp;
+       for_each_populated_zone(zone) {
+               struct per_cpu_pageset *p;
 
-               pcp = zone_pcp(zone, cpu);
+               p = per_cpu_ptr(zone->pageset, cpu);
 
                for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
-                       if (pcp->vm_stat_diff[i]) {
+                       if (p->vm_stat_diff[i]) {
+                               unsigned long flags;
+                               int v;
+
                                local_irq_save(flags);
-                               zone_page_state_add(pcp->vm_stat_diff[i],
-                                       zone, i);
-                               pcp->vm_stat_diff[i] = 0;
+                               v = p->vm_stat_diff[i];
+                               p->vm_stat_diff[i] = 0;
                                local_irq_restore(flags);
+                               atomic_long_add(v, &zone->vm_stat[i]);
+                               global_diff[i] += v;
+#ifdef CONFIG_NUMA
+                               /* 3 seconds idle till flush */
+                               p->expire = 3;
+#endif
                        }
+               cond_resched();
+#ifdef CONFIG_NUMA
+               /*
+                * Deal with draining the remote pageset of this
+                * processor
+                *
+                * Check if there are pages remaining in this pageset
+                * if not then there is nothing to expire.
+                */
+               if (!p->expire || !p->pcp.count)
+                       continue;
+
+               /*
+                * We never drain zones local to this processor.
+                */
+               if (zone_to_nid(zone) == numa_node_id()) {
+                       p->expire = 0;
+                       continue;
+               }
+
+               p->expire--;
+               if (p->expire)
+                       continue;
+
+               if (p->pcp.count)
+                       drain_zone_pages(zone, &p->pcp);
+#endif
        }
+
+       for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
+               if (global_diff[i])
+                       atomic_long_add(global_diff[i], &vm_stat[i]);
 }
 
-static void __refresh_cpu_vm_stats(void *dummy)
+#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 zone *preferred_zone, struct zone *z)
 {
-       refresh_cpu_vm_stats(smp_processor_id());
+       if (z->zone_pgdat == preferred_zone->zone_pgdat) {
+               __inc_zone_state(z, NUMA_HIT);
+       } else {
+               __inc_zone_state(z, NUMA_MISS);
+               __inc_zone_state(preferred_zone, NUMA_FOREIGN);
+       }
+       if (z->node == numa_node_id())
+               __inc_zone_state(z, NUMA_LOCAL);
+       else
+               __inc_zone_state(z, NUMA_OTHER);
 }
+#endif
+
+#ifdef CONFIG_COMPACTION
+struct contig_page_info {
+       unsigned long free_pages;
+       unsigned long free_blocks_total;
+       unsigned long free_blocks_suitable;
+};
 
 /*
- * Consolidate all counters.
- *
- * Note that the result is less inaccurate but still inaccurate
- * if concurrent processes are allowed to run.
+ * Calculate the number of free pages in a zone, how many contiguous
+ * pages are free and how many are large enough to satisfy an allocation of
+ * the target size. Note that this function makes no attempt to estimate
+ * how many suitable free blocks there *might* be if MOVABLE pages were
+ * migrated. Calculating that is possible, but expensive and can be
+ * figured out from userspace
  */
-void refresh_vm_stats(void)
+static void fill_contig_page_info(struct zone *zone,
+                               unsigned int suitable_order,
+                               struct contig_page_info *info)
 {
-       on_each_cpu(__refresh_cpu_vm_stats, NULL, 0, 1);
+       unsigned int order;
+
+       info->free_pages = 0;
+       info->free_blocks_total = 0;
+       info->free_blocks_suitable = 0;
+
+       for (order = 0; order < MAX_ORDER; order++) {
+               unsigned long blocks;
+
+               /* Count number of free blocks */
+               blocks = zone->free_area[order].nr_free;
+               info->free_blocks_total += blocks;
+
+               /* Count free base pages */
+               info->free_pages += blocks << order;
+
+               /* Count the suitable free blocks */
+               if (order >= suitable_order)
+                       info->free_blocks_suitable += blocks <<
+                                               (order - suitable_order);
+       }
 }
-EXPORT_SYMBOL(refresh_vm_stats);
 
-#endif
+/*
+ * A fragmentation index only makes sense if an allocation of a requested
+ * size would fail. If that is true, the fragmentation index indicates
+ * whether external fragmentation or a lack of memory was the problem.
+ * The value can be used to determine if page reclaim or compaction
+ * should be used
+ */
+static int __fragmentation_index(unsigned int order, struct contig_page_info *info)
+{
+       unsigned long requested = 1UL << order;
+
+       if (!info->free_blocks_total)
+               return 0;
+
+       /* Fragmentation index only makes sense when a request would fail */
+       if (info->free_blocks_suitable)
+               return -1000;
+
+       /*
+        * Index is between 0 and 1 so return within 3 decimal places
+        *
+        * 0 => allocation would fail due to lack of memory
+        * 1 => allocation would fail due to fragmentation
+        */
+       return 1000 - div_u64( (1000+(div_u64(info->free_pages * 1000ULL, requested))), info->free_blocks_total);
+}
 
-#ifdef CONFIG_PROC_FS
+/* Same as __fragmentation index but allocs contig_page_info on stack */
+int fragmentation_index(struct zone *zone, unsigned int order)
+{
+       struct contig_page_info info;
+
+       fill_contig_page_info(zone, order, &info);
+       return __fragmentation_index(order, &info);
+}
+#endif
 
+#if defined(CONFIG_PROC_FS) || defined(CONFIG_COMPACTION)
+#include <linux/proc_fs.h>
 #include <linux/seq_file.h>
 
+static char * const migratetype_names[MIGRATE_TYPES] = {
+       "Unmovable",
+       "Reclaimable",
+       "Movable",
+       "Reserve",
+       "Isolate",
+};
+
 static void *frag_start(struct seq_file *m, loff_t *pos)
 {
        pg_data_t *pgdat;
@@ -339,59 +495,259 @@ 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)
+/* Walk all the zones in a node and print using a callback */
+static void walk_zones_in_node(struct seq_file *m, pg_data_t *pgdat,
+               void (*print)(struct seq_file *m, pg_data_t *, struct zone *))
 {
-       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);
+               print(m, pgdat, zone);
                spin_unlock_irqrestore(&zone->lock, flags);
+       }
+}
+#endif
+
+#ifdef CONFIG_PROC_FS
+static void frag_show_print(struct seq_file *m, pg_data_t *pgdat,
+                                               struct zone *zone)
+{
+       int order;
+
+       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);
+       seq_putc(m, '\n');
+}
+
+/*
+ * 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;
+       walk_zones_in_node(m, pgdat, frag_show_print);
+       return 0;
+}
+
+static void pagetypeinfo_showfree_print(struct seq_file *m,
+                                       pg_data_t *pgdat, struct zone *zone)
+{
+       int order, mtype;
+
+       for (mtype = 0; mtype < MIGRATE_TYPES; mtype++) {
+               seq_printf(m, "Node %4d, zone %8s, type %12s ",
+                                       pgdat->node_id,
+                                       zone->name,
+                                       migratetype_names[mtype]);
+               for (order = 0; order < MAX_ORDER; ++order) {
+                       unsigned long freecount = 0;
+                       struct free_area *area;
+                       struct list_head *curr;
+
+                       area = &(zone->free_area[order]);
+
+                       list_for_each(curr, &area->free_list[mtype])
+                               freecount++;
+                       seq_printf(m, "%6lu ", freecount);
+               }
                seq_putc(m, '\n');
        }
+}
+
+/* Print out the free pages at each order for each migatetype */
+static int pagetypeinfo_showfree(struct seq_file *m, void *arg)
+{
+       int order;
+       pg_data_t *pgdat = (pg_data_t *)arg;
+
+       /* Print header */
+       seq_printf(m, "%-43s ", "Free pages count per migrate type at order");
+       for (order = 0; order < MAX_ORDER; ++order)
+               seq_printf(m, "%6d ", order);
+       seq_putc(m, '\n');
+
+       walk_zones_in_node(m, pgdat, pagetypeinfo_showfree_print);
+
+       return 0;
+}
+
+static void pagetypeinfo_showblockcount_print(struct seq_file *m,
+                                       pg_data_t *pgdat, struct zone *zone)
+{
+       int mtype;
+       unsigned long pfn;
+       unsigned long start_pfn = zone->zone_start_pfn;
+       unsigned long end_pfn = start_pfn + zone->spanned_pages;
+       unsigned long count[MIGRATE_TYPES] = { 0, };
+
+       for (pfn = start_pfn; pfn < end_pfn; pfn += pageblock_nr_pages) {
+               struct page *page;
+
+               if (!pfn_valid(pfn))
+                       continue;
+
+               page = pfn_to_page(pfn);
+
+               /* Watch for unexpected holes punched in the memmap */
+               if (!memmap_valid_within(pfn, page, zone))
+                       continue;
+
+               mtype = get_pageblock_migratetype(page);
+
+               if (mtype < MIGRATE_TYPES)
+                       count[mtype]++;
+       }
+
+       /* Print counts */
+       seq_printf(m, "Node %d, zone %8s ", pgdat->node_id, zone->name);
+       for (mtype = 0; mtype < MIGRATE_TYPES; mtype++)
+               seq_printf(m, "%12lu ", count[mtype]);
+       seq_putc(m, '\n');
+}
+
+/* Print out the free pages at each order for each migratetype */
+static int pagetypeinfo_showblockcount(struct seq_file *m, void *arg)
+{
+       int mtype;
+       pg_data_t *pgdat = (pg_data_t *)arg;
+
+       seq_printf(m, "\n%-23s", "Number of blocks type ");
+       for (mtype = 0; mtype < MIGRATE_TYPES; mtype++)
+               seq_printf(m, "%12s ", migratetype_names[mtype]);
+       seq_putc(m, '\n');
+       walk_zones_in_node(m, pgdat, pagetypeinfo_showblockcount_print);
+
+       return 0;
+}
+
+/*
+ * This prints out statistics in relation to grouping pages by mobility.
+ * It is expensive to collect so do not constantly read the file.
+ */
+static int pagetypeinfo_show(struct seq_file *m, void *arg)
+{
+       pg_data_t *pgdat = (pg_data_t *)arg;
+
+       /* check memoryless node */
+       if (!node_state(pgdat->node_id, N_HIGH_MEMORY))
+               return 0;
+
+       seq_printf(m, "Page block order: %d\n", pageblock_order);
+       seq_printf(m, "Pages per block:  %lu\n", pageblock_nr_pages);
+       seq_putc(m, '\n');
+       pagetypeinfo_showfree(m, pgdat);
+       pagetypeinfo_showblockcount(m, pgdat);
+
        return 0;
 }
 
-struct seq_operations fragmentation_op = {
+static const struct seq_operations fragmentation_op = {
        .start  = frag_start,
        .next   = frag_next,
        .stop   = frag_stop,
        .show   = frag_show,
 };
 
-static char *vmstat_text[] = {
+static int fragmentation_open(struct inode *inode, struct file *file)
+{
+       return seq_open(file, &fragmentation_op);
+}
+
+static const struct file_operations fragmentation_file_operations = {
+       .open           = fragmentation_open,
+       .read           = seq_read,
+       .llseek         = seq_lseek,
+       .release        = seq_release,
+};
+
+static const struct seq_operations pagetypeinfo_op = {
+       .start  = frag_start,
+       .next   = frag_next,
+       .stop   = frag_stop,
+       .show   = pagetypeinfo_show,
+};
+
+static int pagetypeinfo_open(struct inode *inode, struct file *file)
+{
+       return seq_open(file, &pagetypeinfo_op);
+}
+
+static const struct file_operations pagetypeinfo_file_ops = {
+       .open           = pagetypeinfo_open,
+       .read           = seq_read,
+       .llseek         = seq_lseek,
+       .release        = seq_release,
+};
+
+#ifdef CONFIG_ZONE_DMA
+#define TEXT_FOR_DMA(xx) xx "_dma",
+#else
+#define TEXT_FOR_DMA(xx)
+#endif
+
+#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) TEXT_FOR_DMA(xx) TEXT_FOR_DMA32(xx) xx "_normal", \
+                                       TEXT_FOR_HIGHMEM(xx) xx "_movable",
+
+static const char * const vmstat_text[] = {
        /* Zoned VM counters */
+       "nr_free_pages",
+       "nr_inactive_anon",
+       "nr_active_anon",
+       "nr_inactive_file",
+       "nr_active_file",
+       "nr_unevictable",
+       "nr_mlock",
        "nr_anon_pages",
        "nr_mapped",
        "nr_file_pages",
-       "nr_slab",
-       "nr_page_table_pages",
        "nr_dirty",
        "nr_writeback",
+       "nr_slab_reclaimable",
+       "nr_slab_unreclaimable",
+       "nr_page_table_pages",
+       "nr_kernel_stack",
        "nr_unstable",
+       "nr_bounce",
+       "nr_vmscan_write",
+       "nr_writeback_temp",
+       "nr_isolated_anon",
+       "nr_isolated_file",
+       "nr_shmem",
+#ifdef CONFIG_NUMA
+       "numa_hit",
+       "numa_miss",
+       "numa_foreign",
+       "numa_interleave",
+       "numa_local",
+       "numa_other",
+#endif
 
-       /* Event counters */
+#ifdef CONFIG_VM_EVENT_COUNTERS
        "pgpgin",
        "pgpgout",
        "pswpin",
        "pswpout",
 
-       "pgalloc_high",
-       "pgalloc_normal",
-       "pgalloc_dma32",
-       "pgalloc_dma",
+       TEXTS_FOR_ZONES("pgalloc")
 
        "pgfree",
        "pgactivate",
@@ -400,142 +756,124 @@ static char *vmstat_text[] = {
        "pgfault",
        "pgmajfault",
 
-       "pgrefill_high",
-       "pgrefill_normal",
-       "pgrefill_dma32",
-       "pgrefill_dma",
-
-       "pgsteal_high",
-       "pgsteal_normal",
-       "pgsteal_dma32",
-       "pgsteal_dma",
-
-       "pgscan_kswapd_high",
-       "pgscan_kswapd_normal",
-       "pgscan_kswapd_dma32",
-       "pgscan_kswapd_dma",
-
-       "pgscan_direct_high",
-       "pgscan_direct_normal",
-       "pgscan_direct_dma32",
-       "pgscan_direct_dma",
+       TEXTS_FOR_ZONES("pgrefill")
+       TEXTS_FOR_ZONES("pgsteal")
+       TEXTS_FOR_ZONES("pgscan_kswapd")
+       TEXTS_FOR_ZONES("pgscan_direct")
 
+#ifdef CONFIG_NUMA
+       "zone_reclaim_failed",
+#endif
        "pginodesteal",
        "slabs_scanned",
        "kswapd_steal",
        "kswapd_inodesteal",
+       "kswapd_low_wmark_hit_quickly",
+       "kswapd_high_wmark_hit_quickly",
+       "kswapd_skip_congestion_wait",
        "pageoutrun",
        "allocstall",
 
        "pgrotated",
-       "nr_bounce",
-};
 
-/*
- * 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;
+#ifdef CONFIG_COMPACTION
+       "compact_blocks_moved",
+       "compact_pages_moved",
+       "compact_pagemigrate_failed",
+       "compact_stall",
+       "compact_fail",
+       "compact_success",
+#endif
 
-               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);
+#ifdef CONFIG_HUGETLB_PAGE
+       "htlb_buddy_alloc_success",
+       "htlb_buddy_alloc_fail",
+#endif
+       "unevictable_pgs_culled",
+       "unevictable_pgs_scanned",
+       "unevictable_pgs_rescued",
+       "unevictable_pgs_mlocked",
+       "unevictable_pgs_munlocked",
+       "unevictable_pgs_cleared",
+       "unevictable_pgs_stranded",
+       "unevictable_pgs_mlockfreed",
+#endif
+};
 
-               for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
-                       seq_printf(m, "\n    %-12s %lu", vmstat_text[i],
-                                       zone_page_state(zone, i));
+static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat,
+                                                       struct zone *zone)
+{
+       int i;
+       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        scanned  %lu"
+                  "\n        spanned  %lu"
+                  "\n        present  %lu",
+                  zone_page_state(zone, NR_FREE_PAGES),
+                  min_wmark_pages(zone),
+                  low_wmark_pages(zone),
+                  high_wmark_pages(zone),
+                  zone->pages_scanned,
+                  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;
+
+               pageset = per_cpu_ptr(zone->pageset, 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_NUMA
-                       seq_printf(m,
-                                  "\n            numa_hit:       %lu"
-                                  "\n            numa_miss:      %lu"
-                                  "\n            numa_foreign:   %lu"
-                                  "\n            interleave_hit: %lu"
-                                  "\n            local_node:     %lu"
-                                  "\n            other_node:     %lu",
-                                  pageset->numa_hit,
-                                  pageset->numa_miss,
-                                  pageset->numa_foreign,
-                                  pageset->interleave_hit,
-                                  pageset->local_node,
-                                  pageset->other_node);
+                          "\n    cpu: %i"
+                          "\n              count: %i"
+                          "\n              high:  %i"
+                          "\n              batch: %i",
+                          i,
+                          pageset->pcp.count,
+                          pageset->pcp.high,
+                          pageset->pcp.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');
        }
+       seq_printf(m,
+                  "\n  all_unreclaimable: %u"
+                  "\n  prev_priority:     %i"
+                  "\n  start_pfn:         %lu"
+                  "\n  inactive_ratio:    %u",
+                  zone->all_unreclaimable,
+                  zone->prev_priority,
+                  zone->zone_start_pfn,
+                  zone->inactive_ratio);
+       seq_putc(m, '\n');
+}
+
+/*
+ * Output information about zones in @pgdat.
+ */
+static int zoneinfo_show(struct seq_file *m, void *arg)
+{
+       pg_data_t *pgdat = (pg_data_t *)arg;
+       walk_zones_in_node(m, pgdat, zoneinfo_show_print);
        return 0;
 }
 
-struct seq_operations zoneinfo_op = {
+static const struct seq_operations zoneinfo_op = {
        .start  = frag_start, /* iterate over all zones. The same as in
                               * fragmentation. */
        .next   = frag_next,
@@ -543,26 +881,47 @@ struct seq_operations zoneinfo_op = {
        .show   = zoneinfo_show,
 };
 
+static int zoneinfo_open(struct inode *inode, struct file *file)
+{
+       return seq_open(file, &zoneinfo_op);
+}
+
+static const struct file_operations proc_zoneinfo_file_operations = {
+       .open           = zoneinfo_open,
+       .read           = seq_read,
+       .llseek         = seq_lseek,
+       .release        = seq_release,
+};
+
 static void *vmstat_start(struct seq_file *m, loff_t *pos)
 {
        unsigned long *v;
-       struct page_state *ps;
+#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(*ps), GFP_KERNEL);
+                       + 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);
-       ps = (struct page_state *)(v + NR_VM_ZONE_STAT_ITEMS);
-       get_full_page_state(ps);
-       ps->pgpgin /= 2;                /* sectors -> kbytes */
-       ps->pgpgout /= 2;
+#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;
 }
 
@@ -589,12 +948,260 @@ static void vmstat_stop(struct seq_file *m, void *arg)
        m->private = NULL;
 }
 
-struct seq_operations vmstat_op = {
+static const struct seq_operations vmstat_op = {
        .start  = vmstat_start,
        .next   = vmstat_next,
        .stop   = vmstat_stop,
        .show   = vmstat_show,
 };
 
+static int vmstat_open(struct inode *inode, struct file *file)
+{
+       return seq_open(file, &vmstat_op);
+}
+
+static const struct file_operations proc_vmstat_file_operations = {
+       .open           = vmstat_open,
+       .read           = seq_read,
+       .llseek         = seq_lseek,
+       .release        = seq_release,
+};
 #endif /* CONFIG_PROC_FS */
 
+#ifdef CONFIG_SMP
+static DEFINE_PER_CPU(struct delayed_work, vmstat_work);
+int sysctl_stat_interval __read_mostly = HZ;
+
+static void vmstat_update(struct work_struct *w)
+{
+       refresh_cpu_vm_stats(smp_processor_id());
+       schedule_delayed_work(&__get_cpu_var(vmstat_work),
+               round_jiffies_relative(sysctl_stat_interval));
+}
+
+static void __cpuinit start_cpu_timer(int cpu)
+{
+       struct delayed_work *work = &per_cpu(vmstat_work, cpu);
+
+       INIT_DELAYED_WORK_DEFERRABLE(work, vmstat_update);
+       schedule_delayed_work_on(cpu, work, __round_jiffies_relative(HZ, cpu));
+}
+
+/*
+ * 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)
+{
+       long cpu = (long)hcpu;
+
+       switch (action) {
+       case CPU_ONLINE:
+       case CPU_ONLINE_FROZEN:
+               start_cpu_timer(cpu);
+               node_set_state(cpu_to_node(cpu), N_CPU);
+               break;
+       case CPU_DOWN_PREPARE:
+       case CPU_DOWN_PREPARE_FROZEN:
+               cancel_rearming_delayed_work(&per_cpu(vmstat_work, cpu));
+               per_cpu(vmstat_work, cpu).work.func = NULL;
+               break;
+       case CPU_DOWN_FAILED:
+       case CPU_DOWN_FAILED_FROZEN:
+               start_cpu_timer(cpu);
+               break;
+       case CPU_DEAD:
+       case CPU_DEAD_FROZEN:
+               refresh_zone_stat_thresholds();
+               break;
+       default:
+               break;
+       }
+       return NOTIFY_OK;
+}
+
+static struct notifier_block __cpuinitdata vmstat_notifier =
+       { &vmstat_cpuup_callback, NULL, 0 };
+#endif
+
+static int __init setup_vmstat(void)
+{
+#ifdef CONFIG_SMP
+       int cpu;
+
+       refresh_zone_stat_thresholds();
+       register_cpu_notifier(&vmstat_notifier);
+
+       for_each_online_cpu(cpu)
+               start_cpu_timer(cpu);
+#endif
+#ifdef CONFIG_PROC_FS
+       proc_create("buddyinfo", S_IRUGO, NULL, &fragmentation_file_operations);
+       proc_create("pagetypeinfo", S_IRUGO, NULL, &pagetypeinfo_file_ops);
+       proc_create("vmstat", S_IRUGO, NULL, &proc_vmstat_file_operations);
+       proc_create("zoneinfo", S_IRUGO, NULL, &proc_zoneinfo_file_operations);
+#endif
+       return 0;
+}
+module_init(setup_vmstat)
+
+#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_COMPACTION)
+#include <linux/debugfs.h>
+
+static struct dentry *extfrag_debug_root;
+
+/*
+ * Return an index indicating how much of the available free memory is
+ * unusable for an allocation of the requested size.
+ */
+static int unusable_free_index(unsigned int order,
+                               struct contig_page_info *info)
+{
+       /* No free memory is interpreted as all free memory is unusable */
+       if (info->free_pages == 0)
+               return 1000;
+
+       /*
+        * Index should be a value between 0 and 1. Return a value to 3
+        * decimal places.
+        *
+        * 0 => no fragmentation
+        * 1 => high fragmentation
+        */
+       return div_u64((info->free_pages - (info->free_blocks_suitable << order)) * 1000ULL, info->free_pages);
+
+}
+
+static void unusable_show_print(struct seq_file *m,
+                                       pg_data_t *pgdat, struct zone *zone)
+{
+       unsigned int order;
+       int index;
+       struct contig_page_info info;
+
+       seq_printf(m, "Node %d, zone %8s ",
+                               pgdat->node_id,
+                               zone->name);
+       for (order = 0; order < MAX_ORDER; ++order) {
+               fill_contig_page_info(zone, order, &info);
+               index = unusable_free_index(order, &info);
+               seq_printf(m, "%d.%03d ", index / 1000, index % 1000);
+       }
+
+       seq_putc(m, '\n');
+}
+
+/*
+ * Display unusable free space index
+ *
+ * The unusable free space index measures how much of the available free
+ * memory cannot be used to satisfy an allocation of a given size and is a
+ * value between 0 and 1. The higher the value, the more of free memory is
+ * unusable and by implication, the worse the external fragmentation is. This
+ * can be expressed as a percentage by multiplying by 100.
+ */
+static int unusable_show(struct seq_file *m, void *arg)
+{
+       pg_data_t *pgdat = (pg_data_t *)arg;
+
+       /* check memoryless node */
+       if (!node_state(pgdat->node_id, N_HIGH_MEMORY))
+               return 0;
+
+       walk_zones_in_node(m, pgdat, unusable_show_print);
+
+       return 0;
+}
+
+static const struct seq_operations unusable_op = {
+       .start  = frag_start,
+       .next   = frag_next,
+       .stop   = frag_stop,
+       .show   = unusable_show,
+};
+
+static int unusable_open(struct inode *inode, struct file *file)
+{
+       return seq_open(file, &unusable_op);
+}
+
+static const struct file_operations unusable_file_ops = {
+       .open           = unusable_open,
+       .read           = seq_read,
+       .llseek         = seq_lseek,
+       .release        = seq_release,
+};
+
+static void extfrag_show_print(struct seq_file *m,
+                                       pg_data_t *pgdat, struct zone *zone)
+{
+       unsigned int order;
+       int index;
+
+       /* Alloc on stack as interrupts are disabled for zone walk */
+       struct contig_page_info info;
+
+       seq_printf(m, "Node %d, zone %8s ",
+                               pgdat->node_id,
+                               zone->name);
+       for (order = 0; order < MAX_ORDER; ++order) {
+               fill_contig_page_info(zone, order, &info);
+               index = __fragmentation_index(order, &info);
+               seq_printf(m, "%d.%03d ", index / 1000, index % 1000);
+       }
+
+       seq_putc(m, '\n');
+}
+
+/*
+ * Display fragmentation index for orders that allocations would fail for
+ */
+static int extfrag_show(struct seq_file *m, void *arg)
+{
+       pg_data_t *pgdat = (pg_data_t *)arg;
+
+       walk_zones_in_node(m, pgdat, extfrag_show_print);
+
+       return 0;
+}
+
+static const struct seq_operations extfrag_op = {
+       .start  = frag_start,
+       .next   = frag_next,
+       .stop   = frag_stop,
+       .show   = extfrag_show,
+};
+
+static int extfrag_open(struct inode *inode, struct file *file)
+{
+       return seq_open(file, &extfrag_op);
+}
+
+static const struct file_operations extfrag_file_ops = {
+       .open           = extfrag_open,
+       .read           = seq_read,
+       .llseek         = seq_lseek,
+       .release        = seq_release,
+};
+
+static int __init extfrag_debug_init(void)
+{
+       extfrag_debug_root = debugfs_create_dir("extfrag", NULL);
+       if (!extfrag_debug_root)
+               return -ENOMEM;
+
+       if (!debugfs_create_file("unusable_index", 0444,
+                       extfrag_debug_root, NULL, &unusable_file_ops))
+               return -ENOMEM;
+
+       if (!debugfs_create_file("extfrag_index", 0444,
+                       extfrag_debug_root, NULL, &extfrag_file_ops))
+               return -ENOMEM;
+
+       return 0;
+}
+
+module_init(extfrag_debug_init);
+#endif