[Bluetooth] Remove unused host controller attributes
[pandora-kernel.git] / mm / vmstat.c
index ee7f896..a2b6a9f 100644 (file)
 #include <linux/config.h>
 #include <linux/mm.h>
 #include <linux/module.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);
-}
-
-void __mod_page_state_offset(unsigned long offset, unsigned long delta)
-{
-       void *ptr;
-
-       ptr = &__get_cpu_var(page_states);
-       *(unsigned long *)(ptr + offset) += delta;
-}
-EXPORT_SYMBOL(__mod_page_state_offset);
-
-void mod_page_state_offset(unsigned long offset, unsigned long delta)
-{
-       unsigned long flags;
-       void *ptr;
-
-       local_irq_save(flags);
-       ptr = &__get_cpu_var(page_states);
-       *(unsigned long *)(ptr + offset) += delta;
-       local_irq_restore(flags);
-}
-EXPORT_SYMBOL(mod_page_state_offset);
+#include <linux/cpu.h>
 
 void __get_zone_counts(unsigned long *active, unsigned long *inactive,
                        unsigned long *free, struct pglist_data *pgdat)
@@ -106,6 +47,64 @@ void get_zone_counts(unsigned long *active,
        }
 }
 
+#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
  *
@@ -116,17 +115,72 @@ 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_zone(zone) {
+
+               if (!zone->present_pages)
+                       continue;
+
+               threshold = calculate_threshold(zone);
+
+               for_each_online_cpu(cpu)
+                       zone_pcp(zone, cpu)->stat_threshold = threshold;
+       }
 }
 
 /*
@@ -135,17 +189,16 @@ 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 = zone_pcp(zone, smp_processor_id());
+       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);
@@ -174,10 +227,12 @@ 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
@@ -187,13 +242,16 @@ EXPORT_SYMBOL(mod_zone_page_state);
  */
 static void __inc_zone_state(struct zone *zone, enum zone_stat_item item)
 {
-       s8 *p = diff_pointer(zone, item);
+       struct per_cpu_pageset *pcp = zone_pcp(zone, smp_processor_id());
+       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;
        }
 }
 
@@ -206,13 +264,16 @@ 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);
-       s8 *p = diff_pointer(zone, item);
+       struct per_cpu_pageset *pcp = zone_pcp(zone, smp_processor_id());
+       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;
        }
 }
 EXPORT_SYMBOL(__dec_zone_page_state);
@@ -241,19 +302,9 @@ 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);
@@ -270,6 +321,9 @@ void refresh_cpu_vm_stats(int cpu)
        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++)
@@ -317,7 +371,7 @@ void zone_statistics(struct zonelist *zonelist, struct zone *z)
                __inc_zone_state(z, NUMA_MISS);
                __inc_zone_state(zonelist->zones[0], NUMA_FOREIGN);
        }
-       if (z->zone_pgdat == NODE_DATA(numa_node_id()))
+       if (z->node == numa_node_id())
                __inc_zone_state(z, NUMA_LOCAL);
        else
                __inc_zone_state(z, NUMA_OTHER);
@@ -384,17 +438,34 @@ struct seq_operations fragmentation_op = {
        .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",
+       "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",
@@ -405,16 +476,13 @@ static char *vmstat_text[] = {
        "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",
@@ -423,25 +491,10 @@ 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")
 
        "pginodesteal",
        "slabs_scanned",
@@ -451,6 +504,7 @@ static char *vmstat_text[] = {
        "allocstall",
 
        "pgrotated",
+#endif
 };
 
 /*
@@ -526,6 +580,10 @@ static int zoneinfo_show(struct seq_file *m, void *arg)
                                           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"
@@ -553,23 +611,32 @@ struct seq_operations zoneinfo_op = {
 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;
 }
 
@@ -605,3 +672,35 @@ struct seq_operations vmstat_op = {
 
 #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