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_dirty;         /* Dirty writeable pages */
  26         unsigned long nr_writeback;     /* Pages under writeback */
  27         unsigned long nr_unstable;      /* NFS unstable pages */
  28         unsigned long nr_page_table_pages;/* Pages used for pagetables */
  29         unsigned long nr_slab;          /* In slab */
  30 #define GET_PAGE_STATE_LAST nr_slab
  31
  32         /*
  33          * The below are zeroed by get_page_state().  Use get_full_page_state()
  34          * to add up all these.
  35          */
  36         unsigned long pgpgin;           /* Disk reads */
  37         unsigned long pgpgout;          /* Disk writes */
  38         unsigned long pswpin;           /* swap reads */
  39         unsigned long pswpout;          /* swap writes */
  40
  41         unsigned long pgalloc_high;     /* page allocations */
  42         unsigned long pgalloc_normal;
  43         unsigned long pgalloc_dma32;
  44         unsigned long pgalloc_dma;
  45
  46         unsigned long pgfree;           /* page freeings */
  47         unsigned long pgactivate;       /* pages moved inactive->active */
  48         unsigned long pgdeactivate;     /* pages moved active->inactive */
  49
  50         unsigned long pgfault;          /* faults (major+minor) */
  51         unsigned long pgmajfault;       /* faults (major only) */
  52
  53         unsigned long pgrefill_high;    /* inspected in refill_inactive_zone */
  54         unsigned long pgrefill_normal;
  55         unsigned long pgrefill_dma32;
  56         unsigned long pgrefill_dma;
  57
  58         unsigned long pgsteal_high;     /* total highmem pages reclaimed */
  59         unsigned long pgsteal_normal;
  60         unsigned long pgsteal_dma32;
  61         unsigned long pgsteal_dma;
  62
  63         unsigned long pgscan_kswapd_high;/* total highmem pages scanned */
  64         unsigned long pgscan_kswapd_normal;
  65         unsigned long pgscan_kswapd_dma32;
  66         unsigned long pgscan_kswapd_dma;
  67
  68         unsigned long pgscan_direct_high;/* total highmem pages scanned */
  69         unsigned long pgscan_direct_normal;
  70         unsigned long pgscan_direct_dma32;
  71         unsigned long pgscan_direct_dma;
  72
  73         unsigned long pginodesteal;     /* pages reclaimed via inode freeing */
  74         unsigned long slabs_scanned;    /* slab objects scanned */
  75         unsigned long kswapd_steal;     /* pages reclaimed by kswapd */
  76         unsigned long kswapd_inodesteal;/* reclaimed via kswapd inode freeing */
  77         unsigned long pageoutrun;       /* kswapd's calls to page reclaim */
  78         unsigned long allocstall;       /* direct reclaim calls */
  79
  80         unsigned long pgrotated;        /* pages rotated to tail of the LRU */
  81         unsigned long nr_bounce;        /* pages for bounce buffers */
  82 };
  83
  84 extern void get_page_state(struct page_state *ret);
  85 extern void get_page_state_node(struct page_state *ret, int node);
  86 extern void get_full_page_state(struct page_state *ret);
  87 extern unsigned long read_page_state_offset(unsigned long offset);
  88 extern void mod_page_state_offset(unsigned long offset, unsigned long delta);
  89 extern void __mod_page_state_offset(unsigned long offset, unsigned long delta);
  90
  91 #define read_page_state(member) \
  92         read_page_state_offset(offsetof(struct page_state, member))
  93
  94 #define mod_page_state(member, delta)   \
  95         mod_page_state_offset(offsetof(struct page_state, member), (delta))
  96
  97 #define __mod_page_state(member, delta) \
  98         __mod_page_state_offset(offsetof(struct page_state, member), (delta))
  99
 100 #define inc_page_state(member)          mod_page_state(member, 1UL)
 101 #define dec_page_state(member)          mod_page_state(member, 0UL - 1)
 102 #define add_page_state(member,delta)    mod_page_state(member, (delta))
 103 #define sub_page_state(member,delta)    mod_page_state(member, 0UL - (delta))
 104
 105 #define __inc_page_state(member)        __mod_page_state(member, 1UL)
 106 #define __dec_page_state(member)        __mod_page_state(member, 0UL - 1)
 107 #define __add_page_state(member,delta)  __mod_page_state(member, (delta))
 108 #define __sub_page_state(member,delta)  __mod_page_state(member, 0UL - (delta))
 109
 110 #define page_state(member) (*__page_state(offsetof(struct page_state, member)))
 111
 112 #define state_zone_offset(zone, member)                                 \
 113 ({                                                                      \
 114         unsigned offset;                                                \
 115         if (is_highmem(zone))                                           \
 116                 offset = offsetof(struct page_state, member##_high);    \
 117         else if (is_normal(zone))                                       \
 118                 offset = offsetof(struct page_state, member##_normal);  \
 119         else if (is_dma32(zone))                                        \
 120                 offset = offsetof(struct page_state, member##_dma32);   \
 121         else                                                            \
 122                 offset = offsetof(struct page_state, member##_dma);     \
 123         offset;                                                         \
 124 })
 125
 126 #define __mod_page_state_zone(zone, member, delta)                      \
 127  do {                                                                   \
 128         __mod_page_state_offset(state_zone_offset(zone, member), (delta)); \
 129  } while (0)
 130
 131 #define mod_page_state_zone(zone, member, delta)                        \
 132  do {                                                                   \
 133         mod_page_state_offset(state_zone_offset(zone, member), (delta)); \
 134  } while (0)
 135
 136 DECLARE_PER_CPU(struct page_state, page_states);
 137
 138 /*
 139  * Zone based page accounting with per cpu differentials.
 140  */
 141 extern atomic_long_t vm_stat[NR_VM_ZONE_STAT_ITEMS];
 142
 143 static inline void zone_page_state_add(long x, struct zone *zone,
 144                                  enum zone_stat_item item)
 145 {
 146         atomic_long_add(x, &zone->vm_stat[item]);
 147         atomic_long_add(x, &vm_stat[item]);
 148 }
 149
 150 static inline unsigned long global_page_state(enum zone_stat_item item)
 151 {
 152         long x = atomic_long_read(&vm_stat[item]);
 153 #ifdef CONFIG_SMP
 154         if (x < 0)
 155                 x = 0;
 156 #endif
 157         return x;
 158 }
 159
 160 static inline unsigned long zone_page_state(struct zone *zone,
 161                                         enum zone_stat_item item)
 162 {
 163         long x = atomic_long_read(&zone->vm_stat[item]);
 164 #ifdef CONFIG_SMP
 165         if (x < 0)
 166                 x = 0;
 167 #endif
 168         return x;
 169 }
 170
 171 #ifdef CONFIG_NUMA
 172 /*
 173  * Determine the per node value of a stat item. This function
 174  * is called frequently in a NUMA machine, so try to be as
 175  * frugal as possible.
 176  */
 177 static inline unsigned long node_page_state(int node,
 178                                  enum zone_stat_item item)
 179 {
 180         struct zone *zones = NODE_DATA(node)->node_zones;
 181
 182         return
 183 #ifndef CONFIG_DMA_IS_NORMAL
 184 #if !defined(CONFIG_DMA_IS_DMA32) && BITS_PER_LONG >= 64
 185                 zone_page_state(&zones[ZONE_DMA32], item) +
 186 #endif
 187                 zone_page_state(&zones[ZONE_NORMAL], item) +
 188 #endif
 189 #ifdef CONFIG_HIGHMEM
 190                 zone_page_state(&zones[ZONE_HIGHMEM], item) +
 191 #endif
 192                 zone_page_state(&zones[ZONE_DMA], item);
 193 }
 194 #else
 195 #define node_page_state(node, item) global_page_state(item)
 196 #endif
 197
 198 #define __add_zone_page_state(__z, __i, __d)    \
 199                 __mod_zone_page_state(__z, __i, __d)
 200 #define __sub_zone_page_state(__z, __i, __d)    \
 201                 __mod_zone_page_state(__z, __i,-(__d))
 202
 203 #define add_zone_page_state(__z, __i, __d) mod_zone_page_state(__z, __i, __d)
 204 #define sub_zone_page_state(__z, __i, __d) mod_zone_page_state(__z, __i, -(__d))
 205
 206 static inline void zap_zone_vm_stats(struct zone *zone)
 207 {
 208         memset(zone->vm_stat, 0, sizeof(zone->vm_stat));
 209 }
 210
 211 #ifdef CONFIG_SMP
 212 void __mod_zone_page_state(struct zone *, enum zone_stat_item 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 void mod_zone_page_state(struct zone *, enum zone_stat_item, int);
 217 void inc_zone_page_state(struct page *, enum zone_stat_item);
 218 void dec_zone_page_state(struct page *, enum zone_stat_item);
 219
 220 extern void inc_zone_state(struct zone *, enum zone_stat_item);
 221
 222 void refresh_cpu_vm_stats(int);
 223 void refresh_vm_stats(void);
 224
 225 #else /* CONFIG_SMP */
 226
 227 /*
 228  * We do not maintain differentials in a single processor configuration.
 229  * The functions directly modify the zone and global counters.
 230  */
 231 static inline void __mod_zone_page_state(struct zone *zone,
 232                         enum zone_stat_item item, int delta)
 233 {
 234         zone_page_state_add(delta, zone, item);
 235 }
 236
 237 static inline void __inc_zone_page_state(struct page *page,
 238                         enum zone_stat_item item)
 239 {
 240         atomic_long_inc(&page_zone(page)->vm_stat[item]);
 241         atomic_long_inc(&vm_stat[item]);
 242 }
 243
 244 static inline void __dec_zone_page_state(struct page *page,
 245                         enum zone_stat_item item)
 246 {
 247         atomic_long_dec(&page_zone(page)->vm_stat[item]);
 248         atomic_long_dec(&vm_stat[item]);
 249 }
 250
 251 /*
 252  * We only use atomic operations to update counters. So there is no need to
 253  * disable interrupts.
 254  */
 255 #define inc_zone_page_state __inc_zone_page_state
 256 #define dec_zone_page_state __dec_zone_page_state
 257 #define mod_zone_page_state __mod_zone_page_state
 258
 259 static inline void refresh_cpu_vm_stats(int cpu) { }
 260 static inline void refresh_vm_stats(void) { }
 261 #endif
 262
 263 #endif /* _LINUX_VMSTAT_H */