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 unsigned long read_page_state_offset(unsigned long offset);
  74 extern void mod_page_state_offset(unsigned long offset, unsigned long delta);
  75 extern void __mod_page_state_offset(unsigned long offset, unsigned long delta);
  76
  77 #define read_page_state(member) \
  78         read_page_state_offset(offsetof(struct page_state, member))
  79
  80 #define mod_page_state(member, delta)   \
  81         mod_page_state_offset(offsetof(struct page_state, member), (delta))
  82
  83 #define __mod_page_state(member, delta) \
  84         __mod_page_state_offset(offsetof(struct page_state, member), (delta))
  85
  86 #define inc_page_state(member)          mod_page_state(member, 1UL)
  87 #define dec_page_state(member)          mod_page_state(member, 0UL - 1)
  88 #define add_page_state(member,delta)    mod_page_state(member, (delta))
  89 #define sub_page_state(member,delta)    mod_page_state(member, 0UL - (delta))
  90
  91 #define __inc_page_state(member)        __mod_page_state(member, 1UL)
  92 #define __dec_page_state(member)        __mod_page_state(member, 0UL - 1)
  93 #define __add_page_state(member,delta)  __mod_page_state(member, (delta))
  94 #define __sub_page_state(member,delta)  __mod_page_state(member, 0UL - (delta))
  95
  96 #define page_state(member) (*__page_state(offsetof(struct page_state, member)))
  97
  98 #define state_zone_offset(zone, member)                                 \
  99 ({                                                                      \
 100         unsigned offset;                                                \
 101         if (is_highmem(zone))                                           \
 102                 offset = offsetof(struct page_state, member##_high);    \
 103         else if (is_normal(zone))                                       \
 104                 offset = offsetof(struct page_state, member##_normal);  \
 105         else if (is_dma32(zone))                                        \
 106                 offset = offsetof(struct page_state, member##_dma32);   \
 107         else                                                            \
 108                 offset = offsetof(struct page_state, member##_dma);     \
 109         offset;                                                         \
 110 })
 111
 112 #define __mod_page_state_zone(zone, member, delta)                      \
 113  do {                                                                   \
 114         __mod_page_state_offset(state_zone_offset(zone, member), (delta)); \
 115  } while (0)
 116
 117 #define mod_page_state_zone(zone, member, delta)                        \
 118  do {                                                                   \
 119         mod_page_state_offset(state_zone_offset(zone, member), (delta)); \
 120  } while (0)
 121
 122 DECLARE_PER_CPU(struct page_state, page_states);
 123
 124 /*
 125  * Zone based page accounting with per cpu differentials.
 126  */
 127 extern atomic_long_t vm_stat[NR_VM_ZONE_STAT_ITEMS];
 128
 129 static inline void zone_page_state_add(long x, struct zone *zone,
 130                                  enum zone_stat_item item)
 131 {
 132         atomic_long_add(x, &zone->vm_stat[item]);
 133         atomic_long_add(x, &vm_stat[item]);
 134 }
 135
 136 static inline unsigned long global_page_state(enum zone_stat_item item)
 137 {
 138         long x = atomic_long_read(&vm_stat[item]);
 139 #ifdef CONFIG_SMP
 140         if (x < 0)
 141                 x = 0;
 142 #endif
 143         return x;
 144 }
 145
 146 static inline unsigned long zone_page_state(struct zone *zone,
 147                                         enum zone_stat_item item)
 148 {
 149         long x = atomic_long_read(&zone->vm_stat[item]);
 150 #ifdef CONFIG_SMP
 151         if (x < 0)
 152                 x = 0;
 153 #endif
 154         return x;
 155 }
 156
 157 #ifdef CONFIG_NUMA
 158 /*
 159  * Determine the per node value of a stat item. This function
 160  * is called frequently in a NUMA machine, so try to be as
 161  * frugal as possible.
 162  */
 163 static inline unsigned long node_page_state(int node,
 164                                  enum zone_stat_item item)
 165 {
 166         struct zone *zones = NODE_DATA(node)->node_zones;
 167
 168         return
 169 #ifndef CONFIG_DMA_IS_NORMAL
 170 #if !defined(CONFIG_DMA_IS_DMA32) && BITS_PER_LONG >= 64
 171                 zone_page_state(&zones[ZONE_DMA32], item) +
 172 #endif
 173                 zone_page_state(&zones[ZONE_NORMAL], item) +
 174 #endif
 175 #ifdef CONFIG_HIGHMEM
 176                 zone_page_state(&zones[ZONE_HIGHMEM], item) +
 177 #endif
 178                 zone_page_state(&zones[ZONE_DMA], item);
 179 }
 180 #else
 181 #define node_page_state(node, item) global_page_state(item)
 182 #endif
 183
 184 #define __add_zone_page_state(__z, __i, __d)    \
 185                 __mod_zone_page_state(__z, __i, __d)
 186 #define __sub_zone_page_state(__z, __i, __d)    \
 187                 __mod_zone_page_state(__z, __i,-(__d))
 188
 189 #define add_zone_page_state(__z, __i, __d) mod_zone_page_state(__z, __i, __d)
 190 #define sub_zone_page_state(__z, __i, __d) mod_zone_page_state(__z, __i, -(__d))
 191
 192 static inline void zap_zone_vm_stats(struct zone *zone)
 193 {
 194         memset(zone->vm_stat, 0, sizeof(zone->vm_stat));
 195 }
 196
 197 #ifdef CONFIG_SMP
 198 void __mod_zone_page_state(struct zone *, enum zone_stat_item item, int);
 199 void __inc_zone_page_state(struct page *, enum zone_stat_item);
 200 void __dec_zone_page_state(struct page *, enum zone_stat_item);
 201
 202 void mod_zone_page_state(struct zone *, enum zone_stat_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 extern void inc_zone_state(struct zone *, enum zone_stat_item);
 207
 208 void refresh_cpu_vm_stats(int);
 209 void refresh_vm_stats(void);
 210
 211 #else /* CONFIG_SMP */
 212
 213 /*
 214  * We do not maintain differentials in a single processor configuration.
 215  * The functions directly modify the zone and global counters.
 216  */
 217 static inline void __mod_zone_page_state(struct zone *zone,
 218                         enum zone_stat_item item, int delta)
 219 {
 220         zone_page_state_add(delta, zone, item);
 221 }
 222
 223 static inline void __inc_zone_page_state(struct page *page,
 224                         enum zone_stat_item item)
 225 {
 226         atomic_long_inc(&page_zone(page)->vm_stat[item]);
 227         atomic_long_inc(&vm_stat[item]);
 228 }
 229
 230 static inline void __dec_zone_page_state(struct page *page,
 231                         enum zone_stat_item item)
 232 {
 233         atomic_long_dec(&page_zone(page)->vm_stat[item]);
 234         atomic_long_dec(&vm_stat[item]);
 235 }
 236
 237 /*
 238  * We only use atomic operations to update counters. So there is no need to
 239  * disable interrupts.
 240  */
 241 #define inc_zone_page_state __inc_zone_page_state
 242 #define dec_zone_page_state __dec_zone_page_state
 243 #define mod_zone_page_state __mod_zone_page_state
 244
 245 static inline void refresh_cpu_vm_stats(int cpu) { }
 246 static inline void refresh_vm_stats(void) { }
 247 #endif
 248
 249 #endif /* _LINUX_VMSTAT_H */