include/linux/vmstat.h

   1 #ifndef _LINUX_VMSTAT_H
   2 #define _LINUX_VMSTAT_H
   3
   4 #include <linux/types.h>
   5 #include <linux/percpu.h>
   6 #include <linux/mm.h>
   7 #include <linux/mmzone.h>
   8 #include <linux/vm_event_item.h>
   9 #include <linux/atomic.h>
  10
  11 extern int sysctl_stat_interval;
  12
  13 #ifdef CONFIG_VM_EVENT_COUNTERS
  14 /*
  15  * Light weight per cpu counter implementation.
  16  *
  17  * Counters should only be incremented and no critical kernel component
  18  * should rely on the counter values.
  19  *
  20  * Counters are handled completely inline. On many platforms the code
  21  * generated will simply be the increment of a global address.
  22  */
  23
  24 struct vm_event_state {
  25         unsigned long event[NR_VM_EVENT_ITEMS];
  26 };
  27
  28 DECLARE_PER_CPU(struct vm_event_state, vm_event_states);
  29
  30 /*
  31  * vm counters are allowed to be racy. Use raw_cpu_ops to avoid the
  32  * local_irq_disable overhead.
  33  */
  34 static inline void __count_vm_event(enum vm_event_item item)
  35 {
  36         raw_cpu_inc(vm_event_states.event[item]);
  37 }
  38
  39 static inline void count_vm_event(enum vm_event_item item)
  40 {
  41         this_cpu_inc(vm_event_states.event[item]);
  42 }
  43
  44 static inline void __count_vm_events(enum vm_event_item item, long delta)
  45 {
  46         raw_cpu_add(vm_event_states.event[item], delta);
  47 }
  48
  49 static inline void count_vm_events(enum vm_event_item item, long delta)
  50 {
  51         this_cpu_add(vm_event_states.event[item], delta);
  52 }
  53
  54 extern void all_vm_events(unsigned long *);
  55
  56 extern void vm_events_fold_cpu(int cpu);
  57
  58 #else
  59
  60 /* Disable counters */
  61 static inline void count_vm_event(enum vm_event_item item)
  62 {
  63 }
  64 static inline void count_vm_events(enum vm_event_item item, long delta)
  65 {
  66 }
  67 static inline void __count_vm_event(enum vm_event_item item)
  68 {
  69 }
  70 static inline void __count_vm_events(enum vm_event_item item, long delta)
  71 {
  72 }
  73 static inline void all_vm_events(unsigned long *ret)
  74 {
  75 }
  76 static inline void vm_events_fold_cpu(int cpu)
  77 {
  78 }
  79
  80 #endif /* CONFIG_VM_EVENT_COUNTERS */
  81
  82 #ifdef CONFIG_NUMA_BALANCING
  83 #define count_vm_numa_event(x)     count_vm_event(x)
  84 #define count_vm_numa_events(x, y) count_vm_events(x, y)
  85 #else
  86 #define count_vm_numa_event(x) do {} while (0)
  87 #define count_vm_numa_events(x, y) do { (void)(y); } while (0)
  88 #endif /* CONFIG_NUMA_BALANCING */
  89
  90 #ifdef CONFIG_DEBUG_TLBFLUSH
  91 #define count_vm_tlb_event(x)      count_vm_event(x)
  92 #define count_vm_tlb_events(x, y)  count_vm_events(x, y)
  93 #else
  94 #define count_vm_tlb_event(x)     do {} while (0)
  95 #define count_vm_tlb_events(x, y) do { (void)(y); } while (0)
  96 #endif
  97
  98 #ifdef CONFIG_DEBUG_VM_VMACACHE
  99 #define count_vm_vmacache_event(x) count_vm_event(x)
 100 #else
 101 #define count_vm_vmacache_event(x) do {} while (0)
 102 #endif
 103
 104 #define __count_zone_vm_events(item, zone, delta) \
 105                 __count_vm_events(item##_NORMAL - ZONE_NORMAL + \
 106                 zone_idx(zone), delta)
 107
 108 /*
 109  * Zone based page accounting with per cpu differentials.
 110  */
 111 extern atomic_long_t vm_stat[NR_VM_ZONE_STAT_ITEMS];
 112
 113 static inline void zone_page_state_add(long x, struct zone *zone,
 114                                  enum zone_stat_item item)
 115 {
 116         atomic_long_add(x, &zone->vm_stat[item]);
 117         atomic_long_add(x, &vm_stat[item]);
 118 }
 119
 120 static inline unsigned long global_page_state(enum zone_stat_item item)
 121 {
 122         long x = atomic_long_read(&vm_stat[item]);
 123 #ifdef CONFIG_SMP
 124         if (x < 0)
 125                 x = 0;
 126 #endif
 127         return x;
 128 }
 129
 130 static inline unsigned long zone_page_state(struct zone *zone,
 131                                         enum zone_stat_item item)
 132 {
 133         long x = atomic_long_read(&zone->vm_stat[item]);
 134 #ifdef CONFIG_SMP
 135         if (x < 0)
 136                 x = 0;
 137 #endif
 138         return x;
 139 }
 140
 141 /*
 142  * More accurate version that also considers the currently pending
 143  * deltas. For that we need to loop over all cpus to find the current
 144  * deltas. There is no synchronization so the result cannot be
 145  * exactly accurate either.
 146  */
 147 static inline unsigned long zone_page_state_snapshot(struct zone *zone,
 148                                         enum zone_stat_item item)
 149 {
 150         long x = atomic_long_read(&zone->vm_stat[item]);
 151
 152 #ifdef CONFIG_SMP
 153         int cpu;
 154         for_each_online_cpu(cpu)
 155                 x += per_cpu_ptr(zone->pageset, cpu)->vm_stat_diff[item];
 156
 157         if (x < 0)
 158                 x = 0;
 159 #endif
 160         return x;
 161 }
 162
 163 #ifdef CONFIG_NUMA
 164 /*
 165  * Determine the per node value of a stat item. This function
 166  * is called frequently in a NUMA machine, so try to be as
 167  * frugal as possible.
 168  */
 169 static inline unsigned long node_page_state(int node,
 170                                  enum zone_stat_item item)
 171 {
 172         struct zone *zones = NODE_DATA(node)->node_zones;
 173
 174         return
 175 #ifdef CONFIG_ZONE_DMA
 176                 zone_page_state(&zones[ZONE_DMA], item) +
 177 #endif
 178 #ifdef CONFIG_ZONE_DMA32
 179                 zone_page_state(&zones[ZONE_DMA32], item) +
 180 #endif
 181 #ifdef CONFIG_HIGHMEM
 182                 zone_page_state(&zones[ZONE_HIGHMEM], item) +
 183 #endif
 184                 zone_page_state(&zones[ZONE_NORMAL], item) +
 185                 zone_page_state(&zones[ZONE_MOVABLE], item);
 186 }
 187
 188 extern void zone_statistics(struct zone *, struct zone *, gfp_t gfp);
 189
 190 #else
 191
 192 #define node_page_state(node, item) global_page_state(item)
 193 #define zone_statistics(_zl, _z, gfp) do { } while (0)
 194
 195 #endif /* CONFIG_NUMA */
 196
 197 #define add_zone_page_state(__z, __i, __d) mod_zone_page_state(__z, __i, __d)
 198 #define sub_zone_page_state(__z, __i, __d) mod_zone_page_state(__z, __i, -(__d))
 199
 200 #ifdef CONFIG_SMP
 201 void __mod_zone_page_state(struct zone *, enum zone_stat_item item, int);
 202 void __inc_zone_page_state(struct page *, enum zone_stat_item);
 203 void __dec_zone_page_state(struct page *, enum zone_stat_item);
 204
 205 void mod_zone_page_state(struct zone *, enum zone_stat_item, int);
 206 void inc_zone_page_state(struct page *, enum zone_stat_item);
 207 void dec_zone_page_state(struct page *, enum zone_stat_item);
 208
 209 extern void inc_zone_state(struct zone *, enum zone_stat_item);
 210 extern void __inc_zone_state(struct zone *, enum zone_stat_item);
 211 extern void dec_zone_state(struct zone *, enum zone_stat_item);
 212 extern void __dec_zone_state(struct zone *, enum zone_stat_item);
 213
 214 void cpu_vm_stats_fold(int cpu);
 215 void refresh_zone_stat_thresholds(void);
 216
 217 void drain_zonestat(struct zone *zone, struct per_cpu_pageset *);
 218
 219 int calculate_pressure_threshold(struct zone *zone);
 220 int calculate_normal_threshold(struct zone *zone);
 221 void set_pgdat_percpu_threshold(pg_data_t *pgdat,
 222                                 int (*calculate_pressure)(struct zone *));
 223 #else /* CONFIG_SMP */
 224
 225 /*
 226  * We do not maintain differentials in a single processor configuration.
 227  * The functions directly modify the zone and global counters.
 228  */
 229 static inline void __mod_zone_page_state(struct zone *zone,
 230                         enum zone_stat_item item, int delta)
 231 {
 232         zone_page_state_add(delta, zone, item);
 233 }
 234
 235 static inline void __inc_zone_state(struct zone *zone, enum zone_stat_item item)
 236 {
 237         atomic_long_inc(&zone->vm_stat[item]);
 238         atomic_long_inc(&vm_stat[item]);
 239 }
 240
 241 static inline void __dec_zone_state(struct zone *zone, enum zone_stat_item item)
 242 {
 243         atomic_long_dec(&zone->vm_stat[item]);
 244         atomic_long_dec(&vm_stat[item]);
 245 }
 246
 247 static inline void __inc_zone_page_state(struct page *page,
 248                         enum zone_stat_item item)
 249 {
 250         __inc_zone_state(page_zone(page), item);
 251 }
 252
 253 static inline void __dec_zone_page_state(struct page *page,
 254                         enum zone_stat_item item)
 255 {
 256         __dec_zone_state(page_zone(page), item);
 257 }
 258
 259 /*
 260  * We only use atomic operations to update counters. So there is no need to
 261  * disable interrupts.
 262  */
 263 #define inc_zone_page_state __inc_zone_page_state
 264 #define dec_zone_page_state __dec_zone_page_state
 265 #define mod_zone_page_state __mod_zone_page_state
 266
 267 #define inc_zone_state __inc_zone_state
 268 #define dec_zone_state __dec_zone_state
 269
 270 #define set_pgdat_percpu_threshold(pgdat, callback) { }
 271
 272 static inline void refresh_cpu_vm_stats(int cpu) { }
 273 static inline void refresh_zone_stat_thresholds(void) { }
 274 static inline void cpu_vm_stats_fold(int cpu) { }
 275
 276 static inline void drain_zonestat(struct zone *zone,
 277                         struct per_cpu_pageset *pset) { }
 278 #endif          /* CONFIG_SMP */
 279
 280 static inline void __mod_zone_freepage_state(struct zone *zone, int nr_pages,
 281                                              int migratetype)
 282 {
 283         __mod_zone_page_state(zone, NR_FREE_PAGES, nr_pages);
 284         if (is_migrate_cma(migratetype))
 285                 __mod_zone_page_state(zone, NR_FREE_CMA_PAGES, nr_pages);
 286 }
 287
 288 extern const char * const vmstat_text[];
 289
 290 #endif /* _LINUX_VMSTAT_H */