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 nr_unstable;      /* NFS unstable pages */
  26 #define GET_PAGE_STATE_LAST nr_unstable
  27
  28         /*
  29          * The below are zeroed by get_page_state().  Use get_full_page_state()
  30          * to add up all these.
  31          */
  32         unsigned long pgpgin;           /* Disk reads */
  33         unsigned long pgpgout;          /* Disk writes */
  34         unsigned long pswpin;           /* swap reads */
  35         unsigned long pswpout;          /* swap writes */
  36
  37         unsigned long pgalloc_high;     /* page allocations */
  38         unsigned long pgalloc_normal;
  39         unsigned long pgalloc_dma32;
  40         unsigned long pgalloc_dma;
  41
  42         unsigned long pgfree;           /* page freeings */
  43         unsigned long pgactivate;       /* pages moved inactive->active */
  44         unsigned long pgdeactivate;     /* pages moved active->inactive */
  45
  46         unsigned long pgfault;          /* faults (major+minor) */
  47         unsigned long pgmajfault;       /* faults (major only) */
  48
  49         unsigned long pgrefill_high;    /* inspected in refill_inactive_zone */
  50         unsigned long pgrefill_normal;
  51         unsigned long pgrefill_dma32;
  52         unsigned long pgrefill_dma;
  53
  54         unsigned long pgsteal_high;     /* total highmem pages reclaimed */
  55         unsigned long pgsteal_normal;
  56         unsigned long pgsteal_dma32;
  57         unsigned long pgsteal_dma;
  58
  59         unsigned long pgscan_kswapd_high;/* total highmem pages scanned */
  60         unsigned long pgscan_kswapd_normal;
  61         unsigned long pgscan_kswapd_dma32;
  62         unsigned long pgscan_kswapd_dma;
  63
  64         unsigned long pgscan_direct_high;/* total highmem pages scanned */
  65         unsigned long pgscan_direct_normal;
  66         unsigned long pgscan_direct_dma32;
  67         unsigned long pgscan_direct_dma;
  68
  69         unsigned long pginodesteal;     /* pages reclaimed via inode freeing */
  70         unsigned long slabs_scanned;    /* slab objects scanned */
  71         unsigned long kswapd_steal;     /* pages reclaimed by kswapd */
  72         unsigned long kswapd_inodesteal;/* reclaimed via kswapd inode freeing */
  73         unsigned long pageoutrun;       /* kswapd's calls to page reclaim */
  74         unsigned long allocstall;       /* direct reclaim calls */
  75
  76         unsigned long pgrotated;        /* pages rotated to tail of the LRU */
  77         unsigned long nr_bounce;        /* pages for bounce buffers */
  78 };
  79
  80 extern void get_page_state(struct page_state *ret);
  81 extern void get_page_state_node(struct page_state *ret, int node);
  82 extern void get_full_page_state(struct page_state *ret);
  83 extern unsigned long read_page_state_offset(unsigned long offset);
  84 extern void mod_page_state_offset(unsigned long offset, unsigned long delta);
  85 extern void __mod_page_state_offset(unsigned long offset, unsigned long delta);
  86
  87 #define read_page_state(member) \
  88         read_page_state_offset(offsetof(struct page_state, member))
  89
  90 #define mod_page_state(member, delta)   \
  91         mod_page_state_offset(offsetof(struct page_state, member), (delta))
  92
  93 #define __mod_page_state(member, delta) \
  94         __mod_page_state_offset(offsetof(struct page_state, member), (delta))
  95
  96 #define inc_page_state(member)          mod_page_state(member, 1UL)
  97 #define dec_page_state(member)          mod_page_state(member, 0UL - 1)
  98 #define add_page_state(member,delta)    mod_page_state(member, (delta))
  99 #define sub_page_state(member,delta)    mod_page_state(member, 0UL - (delta))
 100
 101 #define __inc_page_state(member)        __mod_page_state(member, 1UL)
 102 #define __dec_page_state(member)        __mod_page_state(member, 0UL - 1)
 103 #define __add_page_state(member,delta)  __mod_page_state(member, (delta))
 104 #define __sub_page_state(member,delta)  __mod_page_state(member, 0UL - (delta))
 105
 106 #define page_state(member) (*__page_state(offsetof(struct page_state, member)))
 107
 108 #define state_zone_offset(zone, member)                                 \
 109 ({                                                                      \
 110         unsigned offset;                                                \
 111         if (is_highmem(zone))                                           \
 112                 offset = offsetof(struct page_state, member##_high);    \
 113         else if (is_normal(zone))                                       \
 114                 offset = offsetof(struct page_state, member##_normal);  \
 115         else if (is_dma32(zone))                                        \
 116                 offset = offsetof(struct page_state, member##_dma32);   \
 117         else                                                            \
 118                 offset = offsetof(struct page_state, member##_dma);     \
 119         offset;                                                         \
 120 })
 121
 122 #define __mod_page_state_zone(zone, member, delta)                      \
 123  do {                                                                   \
 124         __mod_page_state_offset(state_zone_offset(zone, member), (delta)); \
 125  } while (0)
 126
 127 #define mod_page_state_zone(zone, member, delta)                        \
 128  do {                                                                   \
 129         mod_page_state_offset(state_zone_offset(zone, member), (delta)); \
 130  } while (0)
 131
 132 DECLARE_PER_CPU(struct page_state, page_states);
 133
 134 /*
 135  * Zone based page accounting with per cpu differentials.
 136  */
 137 extern atomic_long_t vm_stat[NR_VM_ZONE_STAT_ITEMS];
 138
 139 static inline void zone_page_state_add(long x, struct zone *zone,
 140                                  enum zone_stat_item item)
 141 {
 142         atomic_long_add(x, &zone->vm_stat[item]);
 143         atomic_long_add(x, &vm_stat[item]);
 144 }
 145
 146 static inline unsigned long global_page_state(enum zone_stat_item item)
 147 {
 148         long x = atomic_long_read(&vm_stat[item]);
 149 #ifdef CONFIG_SMP
 150         if (x < 0)
 151                 x = 0;
 152 #endif
 153         return x;
 154 }
 155
 156 static inline unsigned long zone_page_state(struct zone *zone,
 157                                         enum zone_stat_item item)
 158 {
 159         long x = atomic_long_read(&zone->vm_stat[item]);
 160 #ifdef CONFIG_SMP
 161         if (x < 0)
 162                 x = 0;
 163 #endif
 164         return x;
 165 }
 166
 167 #ifdef CONFIG_NUMA
 168 /*
 169  * Determine the per node value of a stat item. This function
 170  * is called frequently in a NUMA machine, so try to be as
 171  * frugal as possible.
 172  */
 173 static inline unsigned long node_page_state(int node,
 174                                  enum zone_stat_item item)
 175 {
 176         struct zone *zones = NODE_DATA(node)->node_zones;
 177
 178         return
 179 #ifndef CONFIG_DMA_IS_NORMAL
 180 #if !defined(CONFIG_DMA_IS_DMA32) && BITS_PER_LONG >= 64
 181                 zone_page_state(&zones[ZONE_DMA32], item) +
 182 #endif
 183                 zone_page_state(&zones[ZONE_NORMAL], item) +
 184 #endif
 185 #ifdef CONFIG_HIGHMEM
 186                 zone_page_state(&zones[ZONE_HIGHMEM], item) +
 187 #endif
 188                 zone_page_state(&zones[ZONE_DMA], item);
 189 }
 190 #else
 191 #define node_page_state(node, item) global_page_state(item)
 192 #endif
 193
 194 #define __add_zone_page_state(__z, __i, __d)    \
 195                 __mod_zone_page_state(__z, __i, __d)
 196 #define __sub_zone_page_state(__z, __i, __d)    \
 197                 __mod_zone_page_state(__z, __i,-(__d))
 198
 199 #define add_zone_page_state(__z, __i, __d) mod_zone_page_state(__z, __i, __d)
 200 #define sub_zone_page_state(__z, __i, __d) mod_zone_page_state(__z, __i, -(__d))
 201
 202 static inline void zap_zone_vm_stats(struct zone *zone)
 203 {
 204         memset(zone->vm_stat, 0, sizeof(zone->vm_stat));
 205 }
 206
 207 #ifdef CONFIG_SMP
 208 void __mod_zone_page_state(struct zone *, enum zone_stat_item item, int);
 209 void __inc_zone_page_state(struct page *, enum zone_stat_item);
 210 void __dec_zone_page_state(struct page *, enum zone_stat_item);
 211
 212 void mod_zone_page_state(struct zone *, enum zone_stat_item, int);
 213 void inc_zone_page_state(struct page *, enum zone_stat_item);
 214 void dec_zone_page_state(struct page *, enum zone_stat_item);
 215
 216 extern void inc_zone_state(struct zone *, enum zone_stat_item);
 217
 218 void refresh_cpu_vm_stats(int);
 219 void refresh_vm_stats(void);
 220
 221 #else /* CONFIG_SMP */
 222
 223 /*
 224  * We do not maintain differentials in a single processor configuration.
 225  * The functions directly modify the zone and global counters.
 226  */
 227 static inline void __mod_zone_page_state(struct zone *zone,
 228                         enum zone_stat_item item, int delta)
 229 {
 230         zone_page_state_add(delta, zone, item);
 231 }
 232
 233 static inline void __inc_zone_page_state(struct page *page,
 234                         enum zone_stat_item item)
 235 {
 236         atomic_long_inc(&page_zone(page)->vm_stat[item]);
 237         atomic_long_inc(&vm_stat[item]);
 238 }
 239
 240 static inline void __dec_zone_page_state(struct page *page,
 241                         enum zone_stat_item item)
 242 {
 243         atomic_long_dec(&page_zone(page)->vm_stat[item]);
 244         atomic_long_dec(&vm_stat[item]);
 245 }
 246
 247 /*
 248  * We only use atomic operations to update counters. So there is no need to
 249  * disable interrupts.
 250  */
 251 #define inc_zone_page_state __inc_zone_page_state
 252 #define dec_zone_page_state __dec_zone_page_state
 253 #define mod_zone_page_state __mod_zone_page_state
 254
 255 static inline void refresh_cpu_vm_stats(int cpu) { }
 256 static inline void refresh_vm_stats(void) { }
 257 #endif
 258
 259 #endif /* _LINUX_VMSTAT_H */