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