1 files changed, 263 insertions, 0 deletions
diff --git a/include/linux/vmstat.h b/include/linux/vmstat.h
new file mode 100644
index 00000000..65efb92d
--- /dev/null
+++ b/include/linux/vmstat.h
@@ -0,0 +1,263 @@
+#ifndef _LINUX_VMSTAT_H
+#define _LINUX_VMSTAT_H
+
+#include <linux/types.h>
+#include <linux/percpu.h>
+#include <linux/mm.h>
+#include <linux/mmzone.h>
+#include <linux/vm_event_item.h>
+#include <linux/atomic.h>
+
+extern int sysctl_stat_interval;
+
+#ifdef CONFIG_VM_EVENT_COUNTERS
+/*
+ * Light weight per cpu counter implementation.
+ *
+ * Counters should only be incremented and no critical kernel component
+ * should rely on the counter values.
+ *
+ * Counters are handled completely inline. On many platforms the code
+ * generated will simply be the increment of a global address.
+ */
+
+struct vm_event_state {
+	unsigned long event[NR_VM_EVENT_ITEMS];
+};
+
+DECLARE_PER_CPU(struct vm_event_state, vm_event_states);
+
+static inline void __count_vm_event(enum vm_event_item item)
+{
+	__this_cpu_inc(vm_event_states.event[item]);
+}
+
+static inline void count_vm_event(enum vm_event_item item)
+{
+	this_cpu_inc(vm_event_states.event[item]);
+}
+
+static inline void __count_vm_events(enum vm_event_item item, long delta)
+{
+	__this_cpu_add(vm_event_states.event[item], delta);
+}
+
+static inline void count_vm_events(enum vm_event_item item, long delta)
+{
+	this_cpu_add(vm_event_states.event[item], delta);
+}
+
+extern void all_vm_events(unsigned long *);
+#ifdef CONFIG_HOTPLUG
+extern void vm_events_fold_cpu(int cpu);
+#else
+static inline void vm_events_fold_cpu(int cpu)
+{
+}
+#endif
+
+#else
+
+/* Disable counters */
+static inline void count_vm_event(enum vm_event_item item)
+{
+}
+static inline void count_vm_events(enum vm_event_item item, long delta)
+{
+}
+static inline void __count_vm_event(enum vm_event_item item)
+{
+}
+static inline void __count_vm_events(enum vm_event_item item, long delta)
+{
+}
+static inline void all_vm_events(unsigned long *ret)
+{
+}
+static inline void vm_events_fold_cpu(int cpu)
+{
+}
+
+#endif /* CONFIG_VM_EVENT_COUNTERS */
+
+#define __count_zone_vm_events(item, zone, delta) \
+		__count_vm_events(item##_NORMAL - ZONE_NORMAL + \
+		zone_idx(zone), delta)
+
+/*
+ * Zone based page accounting with per cpu differentials.
+ */
+extern atomic_long_t vm_stat[NR_VM_ZONE_STAT_ITEMS];
+
+static inline void zone_page_state_add(long x, struct zone *zone,
+				 enum zone_stat_item item)
+{
+	atomic_long_add(x, &zone->vm_stat[item]);
+	atomic_long_add(x, &vm_stat[item]);
+}
+
+static inline unsigned long global_page_state(enum zone_stat_item item)
+{
+	long x = atomic_long_read(&vm_stat[item]);
+#ifdef CONFIG_SMP
+	if (x < 0)
+		x = 0;
+#endif
+	return x;
+}
+
+static inline unsigned long zone_page_state(struct zone *zone,
+					enum zone_stat_item item)
+{
+	long x = atomic_long_read(&zone->vm_stat[item]);
+#ifdef CONFIG_SMP
+	if (x < 0)
+		x = 0;
+#endif
+	return x;
+}
+
+/*
+ * More accurate version that also considers the currently pending
+ * deltas. For that we need to loop over all cpus to find the current
+ * deltas. There is no synchronization so the result cannot be
+ * exactly accurate either.
+ */
+static inline unsigned long zone_page_state_snapshot(struct zone *zone,
+					enum zone_stat_item item)
+{
+	long x = atomic_long_read(&zone->vm_stat[item]);
+
+#ifdef CONFIG_SMP
+	int cpu;
+	for_each_online_cpu(cpu)
+		x += per_cpu_ptr(zone->pageset, cpu)->vm_stat_diff[item];
+
+	if (x < 0)
+		x = 0;
+#endif
+	return x;
+}
+
+extern unsigned long global_reclaimable_pages(void);
+extern unsigned long zone_reclaimable_pages(struct zone *zone);
+
+#ifdef CONFIG_NUMA
+/*
+ * Determine the per node value of a stat item. This function
+ * is called frequently in a NUMA machine, so try to be as
+ * frugal as possible.
+ */
+static inline unsigned long node_page_state(int node,
+				 enum zone_stat_item item)
+{
+	struct zone *zones = NODE_DATA(node)->node_zones;
+
+	return
+#ifdef CONFIG_ZONE_DMA
+		zone_page_state(&zones[ZONE_DMA], item) +
+#endif
+#ifdef CONFIG_ZONE_DMA32
+		zone_page_state(&zones[ZONE_DMA32], item) +
+#endif
+#ifdef CONFIG_HIGHMEM
+		zone_page_state(&zones[ZONE_HIGHMEM], item) +
+#endif
+		zone_page_state(&zones[ZONE_NORMAL], item) +
+		zone_page_state(&zones[ZONE_MOVABLE], item);
+}
+
+extern void zone_statistics(struct zone *, struct zone *, gfp_t gfp);
+
+#else
+
+#define node_page_state(node, item) global_page_state(item)
+#define zone_statistics(_zl, _z, gfp) do { } while (0)
+
+#endif /* CONFIG_NUMA */
+
+#define add_zone_page_state(__z, __i, __d) mod_zone_page_state(__z, __i, __d)
+#define sub_zone_page_state(__z, __i, __d) mod_zone_page_state(__z, __i, -(__d))
+
+static inline void zap_zone_vm_stats(struct zone *zone)
+{
+	memset(zone->vm_stat, 0, sizeof(zone->vm_stat));
+}
+
+extern void inc_zone_state(struct zone *, enum zone_stat_item);
+
+#ifdef CONFIG_SMP
+void __mod_zone_page_state(struct zone *, enum zone_stat_item item, int);
+void __inc_zone_page_state(struct page *, enum zone_stat_item);
+void __dec_zone_page_state(struct page *, enum zone_stat_item);
+
+void mod_zone_page_state(struct zone *, enum zone_stat_item, int);
+void inc_zone_page_state(struct page *, enum zone_stat_item);
+void dec_zone_page_state(struct page *, enum zone_stat_item);
+
+extern void inc_zone_state(struct zone *, enum zone_stat_item);
+extern void __inc_zone_state(struct zone *, enum zone_stat_item);
+extern void dec_zone_state(struct zone *, enum zone_stat_item);
+extern void __dec_zone_state(struct zone *, enum zone_stat_item);
+
+void refresh_cpu_vm_stats(int);
+void refresh_zone_stat_thresholds(void);
+
+int calculate_pressure_threshold(struct zone *zone);
+int calculate_normal_threshold(struct zone *zone);
+void set_pgdat_percpu_threshold(pg_data_t *pgdat,
+				int (*calculate_pressure)(struct zone *));
+#else /* CONFIG_SMP */
+
+/*
+ * We do not maintain differentials in a single processor configuration.
+ * The functions directly modify the zone and global counters.
+ */
+static inline void __mod_zone_page_state(struct zone *zone,
+			enum zone_stat_item item, int delta)
+{
+	zone_page_state_add(delta, zone, item);
+}
+
+static inline void __inc_zone_state(struct zone *zone, enum zone_stat_item item)
+{
+	atomic_long_inc(&zone->vm_stat[item]);
+	atomic_long_inc(&vm_stat[item]);
+}
+
+static inline void __inc_zone_page_state(struct page *page,
+			enum zone_stat_item item)
+{
+	__inc_zone_state(page_zone(page), item);
+}
+
+static inline void __dec_zone_state(struct zone *zone, enum zone_stat_item item)
+{
+	atomic_long_dec(&zone->vm_stat[item]);
+	atomic_long_dec(&vm_stat[item]);
+}
+
+static inline void __dec_zone_page_state(struct page *page,
+			enum zone_stat_item item)
+{
+	__dec_zone_state(page_zone(page), item);
+}
+
+/*
+ * We only use atomic operations to update counters. So there is no need to
+ * disable interrupts.
+ */
+#define inc_zone_page_state __inc_zone_page_state
+#define dec_zone_page_state __dec_zone_page_state
+#define mod_zone_page_state __mod_zone_page_state
+
+#define set_pgdat_percpu_threshold(pgdat, callback) { }
+
+static inline void refresh_cpu_vm_stats(int cpu) { }
+static inline void refresh_zone_stat_thresholds(void) { }
+
+#endif		/* CONFIG_SMP */
+
+extern const char * const vmstat_text[];
+
+#endif /* _LINUX_VMSTAT_H */