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vmstat.h
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1 #ifndef _LINUX_VMSTAT_H
2 #define _LINUX_VMSTAT_H
3 
4 #include <linux/types.h>
5 #include <linux/percpu.h>
6 #include <linux/mm.h>
7 #include <linux/mmzone.h>
8 #include <linux/vm_event_item.h>
9 #include <linux/atomic.h>
10 
11 extern int sysctl_stat_interval;
12 
13 #ifdef CONFIG_VM_EVENT_COUNTERS
14 /*
15  * Light weight per cpu counter implementation.
16  *
17  * Counters should only be incremented and no critical kernel component
18  * should rely on the counter values.
19  *
20  * Counters are handled completely inline. On many platforms the code
21  * generated will simply be the increment of a global address.
22  */
23 
24 struct vm_event_state {
25  unsigned long event[NR_VM_EVENT_ITEMS];
26 };
27 
28 DECLARE_PER_CPU(struct vm_event_state, vm_event_states);
29 
30 static inline void __count_vm_event(enum vm_event_item item)
31 {
32  __this_cpu_inc(vm_event_states.event[item]);
33 }
34 
35 static inline void count_vm_event(enum vm_event_item item)
36 {
37  this_cpu_inc(vm_event_states.event[item]);
38 }
39 
40 static inline void __count_vm_events(enum vm_event_item item, long delta)
41 {
42  __this_cpu_add(vm_event_states.event[item], delta);
43 }
44 
45 static inline void count_vm_events(enum vm_event_item item, long delta)
46 {
47  this_cpu_add(vm_event_states.event[item], delta);
48 }
49 
50 extern void all_vm_events(unsigned long *);
51 #ifdef CONFIG_HOTPLUG
52 extern void vm_events_fold_cpu(int cpu);
53 #else
54 static inline void vm_events_fold_cpu(int cpu)
55 {
56 }
57 #endif
58 
59 #else
60 
61 /* Disable counters */
62 static inline void count_vm_event(enum vm_event_item item)
63 {
64 }
65 static inline void count_vm_events(enum vm_event_item item, long delta)
66 {
67 }
68 static inline void __count_vm_event(enum vm_event_item item)
69 {
70 }
71 static inline void __count_vm_events(enum vm_event_item item, long delta)
72 {
73 }
74 static inline void all_vm_events(unsigned long *ret)
75 {
76 }
77 static inline void vm_events_fold_cpu(int cpu)
78 {
79 }
80 
81 #endif /* CONFIG_VM_EVENT_COUNTERS */
82 
83 #define __count_zone_vm_events(item, zone, delta) \
84  __count_vm_events(item##_NORMAL - ZONE_NORMAL + \
85  zone_idx(zone), delta)
86 
87 /*
88  * Zone based page accounting with per cpu differentials.
89  */
91 
92 static inline void zone_page_state_add(long x, struct zone *zone,
93  enum zone_stat_item item)
94 {
95  atomic_long_add(x, &zone->vm_stat[item]);
96  atomic_long_add(x, &vm_stat[item]);
97 }
98 
99 static inline unsigned long global_page_state(enum zone_stat_item item)
100 {
101  long x = atomic_long_read(&vm_stat[item]);
102 #ifdef CONFIG_SMP
103  if (x < 0)
104  x = 0;
105 #endif
106  return x;
107 }
108 
109 static inline unsigned long zone_page_state(struct zone *zone,
110  enum zone_stat_item item)
111 {
112  long x = atomic_long_read(&zone->vm_stat[item]);
113 #ifdef CONFIG_SMP
114  if (x < 0)
115  x = 0;
116 #endif
117  return x;
118 }
119 
120 /*
121  * More accurate version that also considers the currently pending
122  * deltas. For that we need to loop over all cpus to find the current
123  * deltas. There is no synchronization so the result cannot be
124  * exactly accurate either.
125  */
126 static inline unsigned long zone_page_state_snapshot(struct zone *zone,
127  enum zone_stat_item item)
128 {
129  long x = atomic_long_read(&zone->vm_stat[item]);
130 
131 #ifdef CONFIG_SMP
132  int cpu;
134  x += per_cpu_ptr(zone->pageset, cpu)->vm_stat_diff[item];
135 
136  if (x < 0)
137  x = 0;
138 #endif
139  return x;
140 }
141 
142 extern unsigned long global_reclaimable_pages(void);
143 extern unsigned long zone_reclaimable_pages(struct zone *zone);
144 
145 #ifdef CONFIG_NUMA
146 /*
147  * Determine the per node value of a stat item. This function
148  * is called frequently in a NUMA machine, so try to be as
149  * frugal as possible.
150  */
151 static inline unsigned long node_page_state(int node,
152  enum zone_stat_item item)
153 {
154  struct zone *zones = NODE_DATA(node)->node_zones;
155 
156  return
157 #ifdef CONFIG_ZONE_DMA
158  zone_page_state(&zones[ZONE_DMA], item) +
159 #endif
160 #ifdef CONFIG_ZONE_DMA32
161  zone_page_state(&zones[ZONE_DMA32], item) +
162 #endif
163 #ifdef CONFIG_HIGHMEM
164  zone_page_state(&zones[ZONE_HIGHMEM], item) +
165 #endif
166  zone_page_state(&zones[ZONE_NORMAL], item) +
167  zone_page_state(&zones[ZONE_MOVABLE], item);
168 }
169 
170 extern void zone_statistics(struct zone *, struct zone *, gfp_t gfp);
171 
172 #else
173 
174 #define node_page_state(node, item) global_page_state(item)
175 #define zone_statistics(_zl, _z, gfp) do { } while (0)
176 
177 #endif /* CONFIG_NUMA */
178 
179 #define add_zone_page_state(__z, __i, __d) mod_zone_page_state(__z, __i, __d)
180 #define sub_zone_page_state(__z, __i, __d) mod_zone_page_state(__z, __i, -(__d))
181 
182 extern void inc_zone_state(struct zone *, enum zone_stat_item);
183 
184 #ifdef CONFIG_SMP
185 void __mod_zone_page_state(struct zone *, enum zone_stat_item item, int);
186 void __inc_zone_page_state(struct page *, enum zone_stat_item);
187 void __dec_zone_page_state(struct page *, enum zone_stat_item);
188 
189 void mod_zone_page_state(struct zone *, enum zone_stat_item, int);
190 void inc_zone_page_state(struct page *, enum zone_stat_item);
191 void dec_zone_page_state(struct page *, enum zone_stat_item);
192 
193 extern void inc_zone_state(struct zone *, enum zone_stat_item);
194 extern void __inc_zone_state(struct zone *, enum zone_stat_item);
195 extern void dec_zone_state(struct zone *, enum zone_stat_item);
196 extern void __dec_zone_state(struct zone *, enum zone_stat_item);
197 
198 void refresh_cpu_vm_stats(int);
199 void refresh_zone_stat_thresholds(void);
200 
201 void drain_zonestat(struct zone *zone, struct per_cpu_pageset *);
202 
203 int calculate_pressure_threshold(struct zone *zone);
204 int calculate_normal_threshold(struct zone *zone);
206  int (*calculate_pressure)(struct zone *));
207 #else /* CONFIG_SMP */
208 
209 /*
210  * We do not maintain differentials in a single processor configuration.
211  * The functions directly modify the zone and global counters.
212  */
213 static inline void __mod_zone_page_state(struct zone *zone,
214  enum zone_stat_item item, int delta)
215 {
216  zone_page_state_add(delta, zone, item);
217 }
218 
219 static inline void __inc_zone_state(struct zone *zone, enum zone_stat_item item)
220 {
221  atomic_long_inc(&zone->vm_stat[item]);
222  atomic_long_inc(&vm_stat[item]);
223 }
224 
225 static inline void __inc_zone_page_state(struct page *page,
226  enum zone_stat_item item)
227 {
228  __inc_zone_state(page_zone(page), item);
229 }
230 
231 static inline void __dec_zone_state(struct zone *zone, enum zone_stat_item item)
232 {
233  atomic_long_dec(&zone->vm_stat[item]);
234  atomic_long_dec(&vm_stat[item]);
235 }
236 
237 static inline void __dec_zone_page_state(struct page *page,
238  enum zone_stat_item item)
239 {
240  __dec_zone_state(page_zone(page), item);
241 }
242 
243 /*
244  * We only use atomic operations to update counters. So there is no need to
245  * disable interrupts.
246  */
247 #define inc_zone_page_state __inc_zone_page_state
248 #define dec_zone_page_state __dec_zone_page_state
249 #define mod_zone_page_state __mod_zone_page_state
250 
251 #define set_pgdat_percpu_threshold(pgdat, callback) { }
252 
253 static inline void refresh_cpu_vm_stats(int cpu) { }
254 static inline void refresh_zone_stat_thresholds(void) { }
255 
256 static inline void drain_zonestat(struct zone *zone,
257  struct per_cpu_pageset *pset) { }
258 #endif /* CONFIG_SMP */
259 
260 static inline void __mod_zone_freepage_state(struct zone *zone, int nr_pages,
261  int migratetype)
262 {
263  __mod_zone_page_state(zone, NR_FREE_PAGES, nr_pages);
264  if (is_migrate_cma(migratetype))
265  __mod_zone_page_state(zone, NR_FREE_CMA_PAGES, nr_pages);
266 }
267 
268 extern const char * const vmstat_text[];
269 
270 #endif /* _LINUX_VMSTAT_H */