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
11extern 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
24struct vm_event_state {
25	unsigned long event[NR_VM_EVENT_ITEMS];
26};
27
28DECLARE_PER_CPU(struct vm_event_state, vm_event_states);
29
30/*
31 * vm counters are allowed to be racy. Use raw_cpu_ops to avoid the
32 * local_irq_disable overhead.
33 */
34static inline void __count_vm_event(enum vm_event_item item)
35{
36	raw_cpu_inc(vm_event_states.event[item]);
37}
38
39static inline void count_vm_event(enum vm_event_item item)
40{
41	this_cpu_inc(vm_event_states.event[item]);
42}
43
44static inline void __count_vm_events(enum vm_event_item item, long delta)
45{
46	raw_cpu_add(vm_event_states.event[item], delta);
47}
48
49static inline void count_vm_events(enum vm_event_item item, long delta)
50{
51	this_cpu_add(vm_event_states.event[item], delta);
52}
53
54extern void all_vm_events(unsigned long *);
55
56extern void vm_events_fold_cpu(int cpu);
57
58#else
59
60/* Disable counters */
61static inline void count_vm_event(enum vm_event_item item)
62{
63}
64static inline void count_vm_events(enum vm_event_item item, long delta)
65{
66}
67static inline void __count_vm_event(enum vm_event_item item)
68{
69}
70static inline void __count_vm_events(enum vm_event_item item, long delta)
71{
72}
73static inline void all_vm_events(unsigned long *ret)
74{
75}
76static inline void vm_events_fold_cpu(int cpu)
77{
78}
79
80#endif /* CONFIG_VM_EVENT_COUNTERS */
81
82#ifdef CONFIG_NUMA_BALANCING
83#define count_vm_numa_event(x)     count_vm_event(x)
84#define count_vm_numa_events(x, y) count_vm_events(x, y)
85#else
86#define count_vm_numa_event(x) do {} while (0)
87#define count_vm_numa_events(x, y) do { (void)(y); } while (0)
88#endif /* CONFIG_NUMA_BALANCING */
89
90#ifdef CONFIG_DEBUG_TLBFLUSH
91#define count_vm_tlb_event(x)	   count_vm_event(x)
92#define count_vm_tlb_events(x, y)  count_vm_events(x, y)
93#else
94#define count_vm_tlb_event(x)     do {} while (0)
95#define count_vm_tlb_events(x, y) do { (void)(y); } while (0)
96#endif
97
98#ifdef CONFIG_DEBUG_VM_VMACACHE
99#define count_vm_vmacache_event(x) count_vm_event(x)
100#else
101#define count_vm_vmacache_event(x) do {} while (0)
102#endif
103
104#define __count_zone_vm_events(item, zone, delta) \
105		__count_vm_events(item##_NORMAL - ZONE_NORMAL + \
106		zone_idx(zone), delta)
107
108/*
109 * Zone based page accounting with per cpu differentials.
110 */
111extern atomic_long_t vm_stat[NR_VM_ZONE_STAT_ITEMS];
112
113static inline void zone_page_state_add(long x, struct zone *zone,
114				 enum zone_stat_item item)
115{
116	atomic_long_add(x, &zone->vm_stat[item]);
117	atomic_long_add(x, &vm_stat[item]);
118}
119
120static inline unsigned long global_page_state(enum zone_stat_item item)
121{
122	long x = atomic_long_read(&vm_stat[item]);
123#ifdef CONFIG_SMP
124	if (x < 0)
125		x = 0;
126#endif
127	return x;
128}
129
130static inline unsigned long zone_page_state(struct zone *zone,
131					enum zone_stat_item item)
132{
133	long x = atomic_long_read(&zone->vm_stat[item]);
134#ifdef CONFIG_SMP
135	if (x < 0)
136		x = 0;
137#endif
138	return x;
139}
140
141/*
142 * More accurate version that also considers the currently pending
143 * deltas. For that we need to loop over all cpus to find the current
144 * deltas. There is no synchronization so the result cannot be
145 * exactly accurate either.
146 */
147static inline unsigned long zone_page_state_snapshot(struct zone *zone,
148					enum zone_stat_item item)
149{
150	long x = atomic_long_read(&zone->vm_stat[item]);
151
152#ifdef CONFIG_SMP
153	int cpu;
154	for_each_online_cpu(cpu)
155		x += per_cpu_ptr(zone->pageset, cpu)->vm_stat_diff[item];
156
157	if (x < 0)
158		x = 0;
159#endif
160	return x;
161}
162
163#ifdef CONFIG_NUMA
164/*
165 * Determine the per node value of a stat item. This function
166 * is called frequently in a NUMA machine, so try to be as
167 * frugal as possible.
168 */
169static inline unsigned long node_page_state(int node,
170				 enum zone_stat_item item)
171{
172	struct zone *zones = NODE_DATA(node)->node_zones;
173
174	return
175#ifdef CONFIG_ZONE_DMA
176		zone_page_state(&zones[ZONE_DMA], item) +
177#endif
178#ifdef CONFIG_ZONE_DMA32
179		zone_page_state(&zones[ZONE_DMA32], item) +
180#endif
181#ifdef CONFIG_HIGHMEM
182		zone_page_state(&zones[ZONE_HIGHMEM], item) +
183#endif
184		zone_page_state(&zones[ZONE_NORMAL], item) +
185		zone_page_state(&zones[ZONE_MOVABLE], item);
186}
187
188extern void zone_statistics(struct zone *, struct zone *, gfp_t gfp);
189
190#else
191
192#define node_page_state(node, item) global_page_state(item)
193#define zone_statistics(_zl, _z, gfp) do { } while (0)
194
195#endif /* CONFIG_NUMA */
196
197#define add_zone_page_state(__z, __i, __d) mod_zone_page_state(__z, __i, __d)
198#define sub_zone_page_state(__z, __i, __d) mod_zone_page_state(__z, __i, -(__d))
199
200#ifdef CONFIG_SMP
201void __mod_zone_page_state(struct zone *, enum zone_stat_item item, int);
202void __inc_zone_page_state(struct page *, enum zone_stat_item);
203void __dec_zone_page_state(struct page *, enum zone_stat_item);
204
205void mod_zone_page_state(struct zone *, enum zone_stat_item, int);
206void inc_zone_page_state(struct page *, enum zone_stat_item);
207void dec_zone_page_state(struct page *, enum zone_stat_item);
208
209extern void inc_zone_state(struct zone *, enum zone_stat_item);
210extern void __inc_zone_state(struct zone *, enum zone_stat_item);
211extern void dec_zone_state(struct zone *, enum zone_stat_item);
212extern void __dec_zone_state(struct zone *, enum zone_stat_item);
213
214void cpu_vm_stats_fold(int cpu);
215void refresh_zone_stat_thresholds(void);
216
217void drain_zonestat(struct zone *zone, struct per_cpu_pageset *);
218
219int calculate_pressure_threshold(struct zone *zone);
220int calculate_normal_threshold(struct zone *zone);
221void set_pgdat_percpu_threshold(pg_data_t *pgdat,
222				int (*calculate_pressure)(struct zone *));
223#else /* CONFIG_SMP */
224
225/*
226 * We do not maintain differentials in a single processor configuration.
227 * The functions directly modify the zone and global counters.
228 */
229static inline void __mod_zone_page_state(struct zone *zone,
230			enum zone_stat_item item, int delta)
231{
232	zone_page_state_add(delta, zone, item);
233}
234
235static inline void __inc_zone_state(struct zone *zone, enum zone_stat_item item)
236{
237	atomic_long_inc(&zone->vm_stat[item]);
238	atomic_long_inc(&vm_stat[item]);
239}
240
241static inline void __dec_zone_state(struct zone *zone, enum zone_stat_item item)
242{
243	atomic_long_dec(&zone->vm_stat[item]);
244	atomic_long_dec(&vm_stat[item]);
245}
246
247static inline void __inc_zone_page_state(struct page *page,
248			enum zone_stat_item item)
249{
250	__inc_zone_state(page_zone(page), item);
251}
252
253static inline void __dec_zone_page_state(struct page *page,
254			enum zone_stat_item item)
255{
256	__dec_zone_state(page_zone(page), item);
257}
258
259/*
260 * We only use atomic operations to update counters. So there is no need to
261 * disable interrupts.
262 */
263#define inc_zone_page_state __inc_zone_page_state
264#define dec_zone_page_state __dec_zone_page_state
265#define mod_zone_page_state __mod_zone_page_state
266
267#define inc_zone_state __inc_zone_state
268#define dec_zone_state __dec_zone_state
269
270#define set_pgdat_percpu_threshold(pgdat, callback) { }
271
272static inline void refresh_cpu_vm_stats(int cpu) { }
273static inline void refresh_zone_stat_thresholds(void) { }
274static inline void cpu_vm_stats_fold(int cpu) { }
275
276static inline void drain_zonestat(struct zone *zone,
277			struct per_cpu_pageset *pset) { }
278#endif		/* CONFIG_SMP */
279
280static inline void __mod_zone_freepage_state(struct zone *zone, int nr_pages,
281					     int migratetype)
282{
283	__mod_zone_page_state(zone, NR_FREE_PAGES, nr_pages);
284	if (is_migrate_cma(migratetype))
285		__mod_zone_page_state(zone, NR_FREE_CMA_PAGES, nr_pages);
286}
287
288extern const char * const vmstat_text[];
289
290#endif /* _LINUX_VMSTAT_H */
291