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/config.h>
   7 #include <linux/mmzone.h>
   8 #include <asm/atomic.h>
   9
  10 /*
  11  * Global page accounting.  One instance per CPU.  Only unsigned longs are
  12  * allowed.
  13  *
  14  * - Fields can be modified with xxx_page_state and xxx_page_state_zone at
  15  * any time safely (which protects the instance from modification by
  16  * interrupt.
  17  * - The __xxx_page_state variants can be used safely when interrupts are
  18  * disabled.
  19  * - The __xxx_page_state variants can be used if the field is only
  20  * modified from process context and protected from preemption, or only
  21  * modified from interrupt context.  In this case, the field should be
  22  * commented here.
  23  */
  24 struct page_state {
  25         unsigned long pgpgin;           /* Disk reads */
  26         unsigned long pgpgout;          /* Disk writes */
  27         unsigned long pswpin;           /* swap reads */
  28         unsigned long pswpout;          /* swap writes */
  29
  30         unsigned long pgalloc_high;     /* page allocations */
  31         unsigned long pgalloc_normal;
  32         unsigned long pgalloc_dma32;
  33         unsigned long pgalloc_dma;
  34
  35         unsigned long pgfree;           /* page freeings */
  36         unsigned long pgactivate;       /* pages moved inactive->active */
  37         unsigned long pgdeactivate;     /* pages moved active->inactive */
  38
  39         unsigned long pgfault;          /* faults (major+minor) */
  40         unsigned long pgmajfault;       /* faults (major only) */
  41
  42         unsigned long pgrefill_high;    /* inspected in refill_inactive_zone */
  43         unsigned long pgrefill_normal;
  44         unsigned long pgrefill_dma32;
  45         unsigned long pgrefill_dma;
  46
  47         unsigned long pgsteal_high;     /* total highmem pages reclaimed */
  48         unsigned long pgsteal_normal;
  49         unsigned long pgsteal_dma32;
  50         unsigned long pgsteal_dma;
  51
  52         unsigned long pgscan_kswapd_high;/* total highmem pages scanned */
  53         unsigned long pgscan_kswapd_normal;
  54         unsigned long pgscan_kswapd_dma32;
  55         unsigned long pgscan_kswapd_dma;
  56
  57         unsigned long pgscan_direct_high;/* total highmem pages scanned */
  58         unsigned long pgscan_direct_normal;
  59         unsigned long pgscan_direct_dma32;
  60         unsigned long pgscan_direct_dma;
  61
  62         unsigned long pginodesteal;     /* pages reclaimed via inode freeing */
  63         unsigned long slabs_scanned;    /* slab objects scanned */
  64         unsigned long kswapd_steal;     /* pages reclaimed by kswapd */
  65         unsigned long kswapd_inodesteal;/* reclaimed via kswapd inode freeing */
  66         unsigned long pageoutrun;       /* kswapd's calls to page reclaim */
  67         unsigned long allocstall;       /* direct reclaim calls */
  68
  69         unsigned long pgrotated;        /* pages rotated to tail of the LRU */
  70 };
  71
  72 extern void get_full_page_state(struct page_state *ret);
  73 extern void mod_page_state_offset(unsigned long offset, unsigned long delta);
  74 extern void __mod_page_state_offset(unsigned long offset, unsigned long delta);
  75
  76 #define mod_page_state(member, delta)   \
  77         mod_page_state_offset(offsetof(struct page_state, member), (delta))
  78
  79 #define __mod_page_state(member, delta) \
  80         __mod_page_state_offset(offsetof(struct page_state, member), (delta))
  81
  82 #define inc_page_state(member)          mod_page_state(member, 1UL)
  83 #define dec_page_state(member)          mod_page_state(member, 0UL - 1)
  84 #define add_page_state(member,delta)    mod_page_state(member, (delta))
  85 #define sub_page_state(member,delta)    mod_page_state(member, 0UL - (delta))
  86
  87 #define __inc_page_state(member)        __mod_page_state(member, 1UL)
  88 #define __dec_page_state(member)        __mod_page_state(member, 0UL - 1)
  89 #define __add_page_state(member,delta)  __mod_page_state(member, (delta))
  90 #define __sub_page_state(member,delta)  __mod_page_state(member, 0UL - (delta))
  91
  92 #define page_state(member) (*__page_state(offsetof(struct page_state, member)))
  93
  94 #define state_zone_offset(zone, member)                                 \
  95 ({                                                                      \
  96         unsigned offset;                                                \
  97         if (is_highmem(zone))                                           \
  98                 offset = offsetof(struct page_state, member##_high);    \
  99         else if (is_normal(zone))                                       \
 100                 offset = offsetof(struct page_state, member##_normal);  \
 101         else if (is_dma32(zone))                                        \
 102                 offset = offsetof(struct page_state, member##_dma32);   \
 103         else                                                            \
 104                 offset = offsetof(struct page_state, member##_dma);     \
 105         offset;                                                         \
 106 })
 107
 108 #define __mod_page_state_zone(zone, member, delta)                      \
 109  do {                                                                   \
 110         __mod_page_state_offset(state_zone_offset(zone, member), (delta)); \
 111  } while (0)
 112
 113 #define mod_page_state_zone(zone, member, delta)                        \
 114  do {                                                                   \
 115         mod_page_state_offset(state_zone_offset(zone, member), (delta)); \
 116  } while (0)
 117
 118 DECLARE_PER_CPU(struct page_state, page_states);
 119
 120 /*
 121  * Zone based page accounting with per cpu differentials.
 122  */
 123 extern atomic_long_t vm_stat[NR_VM_ZONE_STAT_ITEMS];
 124
 125 static inline void zone_page_state_add(long x, struct zone *zone,
 126                                  enum zone_stat_item item)
 127 {
 128         atomic_long_add(x, &zone->vm_stat[item]);
 129         atomic_long_add(x, &vm_stat[item]);
 130 }
 131
 132 static inline unsigned long global_page_state(enum zone_stat_item item)
 133 {
 134         long x = atomic_long_read(&vm_stat[item]);
 135 #ifdef CONFIG_SMP
 136         if (x < 0)
 137                 x = 0;
 138 #endif
 139         return x;
 140 }
 141
 142 static inline unsigned long zone_page_state(struct zone *zone,
 143                                         enum zone_stat_item item)
 144 {
 145         long x = atomic_long_read(&zone->vm_stat[item]);
 146 #ifdef CONFIG_SMP
 147         if (x < 0)
 148                 x = 0;
 149 #endif
 150         return x;
 151 }
 152
 153 #ifdef CONFIG_NUMA
 154 /*
 155  * Determine the per node value of a stat item. This function
 156  * is called frequently in a NUMA machine, so try to be as
 157  * frugal as possible.
 158  */
 159 static inline unsigned long node_page_state(int node,
 160                                  enum zone_stat_item item)
 161 {
 162         struct zone *zones = NODE_DATA(node)->node_zones;
 163
 164         return
 165 #ifndef CONFIG_DMA_IS_NORMAL
 166 #if !defined(CONFIG_DMA_IS_DMA32) && BITS_PER_LONG >= 64
 167                 zone_page_state(&zones[ZONE_DMA32], item) +
 168 #endif
 169                 zone_page_state(&zones[ZONE_NORMAL], item) +
 170 #endif
 171 #ifdef CONFIG_HIGHMEM
 172                 zone_page_state(&zones[ZONE_HIGHMEM], item) +
 173 #endif
 174                 zone_page_state(&zones[ZONE_DMA], item);
 175 }
 176
 177 extern void zone_statistics(struct zonelist *, struct zone *);
 178
 179 #else
 180
 181 #define node_page_state(node, item) global_page_state(item)
 182 #define zone_statistics(_zl,_z) do { } while (0)
 183
 184 #endif /* CONFIG_NUMA */
 185
 186 #define __add_zone_page_state(__z, __i, __d)    \
 187                 __mod_zone_page_state(__z, __i, __d)
 188 #define __sub_zone_page_state(__z, __i, __d)    \
 189                 __mod_zone_page_state(__z, __i,-(__d))
 190
 191 #define add_zone_page_state(__z, __i, __d) mod_zone_page_state(__z, __i, __d)
 192 #define sub_zone_page_state(__z, __i, __d) mod_zone_page_state(__z, __i, -(__d))
 193
 194 static inline void zap_zone_vm_stats(struct zone *zone)
 195 {
 196         memset(zone->vm_stat, 0, sizeof(zone->vm_stat));
 197 }
 198
 199 extern void inc_zone_state(struct zone *, enum zone_stat_item);
 200
 201 #ifdef CONFIG_SMP
 202 void __mod_zone_page_state(struct zone *, enum zone_stat_item item, int);
 203 void __inc_zone_page_state(struct page *, enum zone_stat_item);
 204 void __dec_zone_page_state(struct page *, enum zone_stat_item);
 205
 206 void mod_zone_page_state(struct zone *, enum zone_stat_item, int);
 207 void inc_zone_page_state(struct page *, enum zone_stat_item);
 208 void dec_zone_page_state(struct page *, enum zone_stat_item);
 209
 210 extern void inc_zone_state(struct zone *, enum zone_stat_item);
 211
 212 void refresh_cpu_vm_stats(int);
 213 void refresh_vm_stats(void);
 214
 215 #else /* CONFIG_SMP */
 216
 217 /*
 218  * We do not maintain differentials in a single processor configuration.
 219  * The functions directly modify the zone and global counters.
 220  */
 221 static inline void __mod_zone_page_state(struct zone *zone,
 222                         enum zone_stat_item item, int delta)
 223 {
 224         zone_page_state_add(delta, zone, item);
 225 }
 226
 227 static inline void __inc_zone_page_state(struct page *page,
 228                         enum zone_stat_item item)
 229 {
 230         atomic_long_inc(&page_zone(page)->vm_stat[item]);
 231         atomic_long_inc(&vm_stat[item]);
 232 }
 233
 234 static inline void __dec_zone_page_state(struct page *page,
 235                         enum zone_stat_item item)
 236 {
 237         atomic_long_dec(&page_zone(page)->vm_stat[item]);
 238         atomic_long_dec(&vm_stat[item]);
 239 }
 240
 241 /*
 242  * We only use atomic operations to update counters. So there is no need to
 243  * disable interrupts.
 244  */
 245 #define inc_zone_page_state __inc_zone_page_state
 246 #define dec_zone_page_state __dec_zone_page_state
 247 #define mod_zone_page_state __mod_zone_page_state
 248
 249 static inline void refresh_cpu_vm_stats(int cpu) { }
 250 static inline void refresh_vm_stats(void) { }
 251 #endif
 252
 253 #endif /* _LINUX_VMSTAT_H */