[PATCH] zoned vm counters: conversion of nr_writeback to per zone counter
[linux-2.6.git] / 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 */