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Christoph Lameterf6ac2352006-06-30 01:55:32 -07001/*
2 * linux/mm/vmstat.c
3 *
4 * Manages VM statistics
5 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
Christoph Lameter2244b952006-06-30 01:55:33 -07006 *
7 * zoned VM statistics
8 * Copyright (C) 2006 Silicon Graphics, Inc.,
9 * Christoph Lameter <christoph@lameter.com>
Christoph Lameterf6ac2352006-06-30 01:55:32 -070010 */
Alexey Dobriyan8f32f7e2008-10-06 04:13:52 +040011#include <linux/fs.h>
Christoph Lameterf6ac2352006-06-30 01:55:32 -070012#include <linux/mm.h>
Alexey Dobriyan4e950f62007-07-30 02:36:13 +040013#include <linux/err.h>
Christoph Lameter2244b952006-06-30 01:55:33 -070014#include <linux/module.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090015#include <linux/slab.h>
Christoph Lameterdf9ecab2006-08-31 21:27:35 -070016#include <linux/cpu.h>
Adrian Bunkc748e132008-07-23 21:27:03 -070017#include <linux/vmstat.h>
Alexey Dobriyane8edc6e2007-05-21 01:22:52 +040018#include <linux/sched.h>
Mel Gormanf1a5ab12010-05-24 14:32:26 -070019#include <linux/math64.h>
Michael Rubin79da8262010-10-26 14:21:36 -070020#include <linux/writeback.h>
Namhyung Kim36deb0b2010-10-26 14:22:04 -070021#include <linux/compaction.h>
Christoph Lameterf6ac2352006-06-30 01:55:32 -070022
Christoph Lameterf8891e52006-06-30 01:55:45 -070023#ifdef CONFIG_VM_EVENT_COUNTERS
24DEFINE_PER_CPU(struct vm_event_state, vm_event_states) = {{0}};
25EXPORT_PER_CPU_SYMBOL(vm_event_states);
26
Minchan Kim31f961a2010-08-09 17:18:59 -070027static void sum_vm_events(unsigned long *ret)
Christoph Lameterf8891e52006-06-30 01:55:45 -070028{
Christoph Lameter9eccf2a2008-02-04 22:29:22 -080029 int cpu;
Christoph Lameterf8891e52006-06-30 01:55:45 -070030 int i;
31
32 memset(ret, 0, NR_VM_EVENT_ITEMS * sizeof(unsigned long));
33
Minchan Kim31f961a2010-08-09 17:18:59 -070034 for_each_online_cpu(cpu) {
Christoph Lameterf8891e52006-06-30 01:55:45 -070035 struct vm_event_state *this = &per_cpu(vm_event_states, cpu);
36
Christoph Lameterf8891e52006-06-30 01:55:45 -070037 for (i = 0; i < NR_VM_EVENT_ITEMS; i++)
38 ret[i] += this->event[i];
39 }
40}
41
42/*
43 * Accumulate the vm event counters across all CPUs.
44 * The result is unavoidably approximate - it can change
45 * during and after execution of this function.
46*/
47void all_vm_events(unsigned long *ret)
48{
KOSAKI Motohirob5be1132008-05-12 14:02:06 -070049 get_online_cpus();
Minchan Kim31f961a2010-08-09 17:18:59 -070050 sum_vm_events(ret);
KOSAKI Motohirob5be1132008-05-12 14:02:06 -070051 put_online_cpus();
Christoph Lameterf8891e52006-06-30 01:55:45 -070052}
Heiko Carstens32dd66f2006-07-10 04:44:31 -070053EXPORT_SYMBOL_GPL(all_vm_events);
Christoph Lameterf8891e52006-06-30 01:55:45 -070054
Christoph Lameterf8891e52006-06-30 01:55:45 -070055/*
56 * Fold the foreign cpu events into our own.
57 *
58 * This is adding to the events on one processor
59 * but keeps the global counts constant.
60 */
61void vm_events_fold_cpu(int cpu)
62{
63 struct vm_event_state *fold_state = &per_cpu(vm_event_states, cpu);
64 int i;
65
66 for (i = 0; i < NR_VM_EVENT_ITEMS; i++) {
67 count_vm_events(i, fold_state->event[i]);
68 fold_state->event[i] = 0;
69 }
70}
Christoph Lameterf8891e52006-06-30 01:55:45 -070071
72#endif /* CONFIG_VM_EVENT_COUNTERS */
73
Christoph Lameter2244b952006-06-30 01:55:33 -070074/*
75 * Manage combined zone based / global counters
76 *
77 * vm_stat contains the global counters
78 */
Dimitri Sivanicha1cb2c62011-10-31 17:09:46 -070079atomic_long_t vm_stat[NR_VM_ZONE_STAT_ITEMS] __cacheline_aligned_in_smp;
Christoph Lameter2244b952006-06-30 01:55:33 -070080EXPORT_SYMBOL(vm_stat);
81
82#ifdef CONFIG_SMP
83
Mel Gormanb44129b2011-01-13 15:45:43 -080084int calculate_pressure_threshold(struct zone *zone)
Mel Gorman88f5acf2011-01-13 15:45:41 -080085{
86 int threshold;
87 int watermark_distance;
88
89 /*
90 * As vmstats are not up to date, there is drift between the estimated
91 * and real values. For high thresholds and a high number of CPUs, it
92 * is possible for the min watermark to be breached while the estimated
93 * value looks fine. The pressure threshold is a reduced value such
94 * that even the maximum amount of drift will not accidentally breach
95 * the min watermark
96 */
97 watermark_distance = low_wmark_pages(zone) - min_wmark_pages(zone);
98 threshold = max(1, (int)(watermark_distance / num_online_cpus()));
99
100 /*
101 * Maximum threshold is 125
102 */
103 threshold = min(125, threshold);
104
105 return threshold;
106}
107
Mel Gormanb44129b2011-01-13 15:45:43 -0800108int calculate_normal_threshold(struct zone *zone)
Christoph Lameterdf9ecab2006-08-31 21:27:35 -0700109{
110 int threshold;
111 int mem; /* memory in 128 MB units */
112
113 /*
114 * The threshold scales with the number of processors and the amount
115 * of memory per zone. More memory means that we can defer updates for
116 * longer, more processors could lead to more contention.
117 * fls() is used to have a cheap way of logarithmic scaling.
118 *
119 * Some sample thresholds:
120 *
121 * Threshold Processors (fls) Zonesize fls(mem+1)
122 * ------------------------------------------------------------------
123 * 8 1 1 0.9-1 GB 4
124 * 16 2 2 0.9-1 GB 4
125 * 20 2 2 1-2 GB 5
126 * 24 2 2 2-4 GB 6
127 * 28 2 2 4-8 GB 7
128 * 32 2 2 8-16 GB 8
129 * 4 2 2 <128M 1
130 * 30 4 3 2-4 GB 5
131 * 48 4 3 8-16 GB 8
132 * 32 8 4 1-2 GB 4
133 * 32 8 4 0.9-1GB 4
134 * 10 16 5 <128M 1
135 * 40 16 5 900M 4
136 * 70 64 7 2-4 GB 5
137 * 84 64 7 4-8 GB 6
138 * 108 512 9 4-8 GB 6
139 * 125 1024 10 8-16 GB 8
140 * 125 1024 10 16-32 GB 9
141 */
142
Jiang Liub40da042013-02-22 16:33:52 -0800143 mem = zone->managed_pages >> (27 - PAGE_SHIFT);
Christoph Lameterdf9ecab2006-08-31 21:27:35 -0700144
145 threshold = 2 * fls(num_online_cpus()) * (1 + fls(mem));
146
147 /*
148 * Maximum threshold is 125
149 */
150 threshold = min(125, threshold);
151
152 return threshold;
153}
Christoph Lameter2244b952006-06-30 01:55:33 -0700154
155/*
Christoph Lameterdf9ecab2006-08-31 21:27:35 -0700156 * Refresh the thresholds for each zone.
Christoph Lameter2244b952006-06-30 01:55:33 -0700157 */
KOSAKI Motohiroa6cccdc2011-05-24 17:11:33 -0700158void refresh_zone_stat_thresholds(void)
Christoph Lameter2244b952006-06-30 01:55:33 -0700159{
Christoph Lameterdf9ecab2006-08-31 21:27:35 -0700160 struct zone *zone;
161 int cpu;
162 int threshold;
163
KOSAKI Motohiroee99c712009-03-31 15:19:31 -0700164 for_each_populated_zone(zone) {
Christoph Lameteraa454842010-09-09 16:38:17 -0700165 unsigned long max_drift, tolerate_drift;
166
Mel Gormanb44129b2011-01-13 15:45:43 -0800167 threshold = calculate_normal_threshold(zone);
Christoph Lameterdf9ecab2006-08-31 21:27:35 -0700168
169 for_each_online_cpu(cpu)
Christoph Lameter99dcc3e2010-01-05 15:34:51 +0900170 per_cpu_ptr(zone->pageset, cpu)->stat_threshold
171 = threshold;
Christoph Lameteraa454842010-09-09 16:38:17 -0700172
173 /*
174 * Only set percpu_drift_mark if there is a danger that
175 * NR_FREE_PAGES reports the low watermark is ok when in fact
176 * the min watermark could be breached by an allocation
177 */
178 tolerate_drift = low_wmark_pages(zone) - min_wmark_pages(zone);
179 max_drift = num_online_cpus() * threshold;
180 if (max_drift > tolerate_drift)
181 zone->percpu_drift_mark = high_wmark_pages(zone) +
182 max_drift;
Christoph Lameterdf9ecab2006-08-31 21:27:35 -0700183 }
Christoph Lameter2244b952006-06-30 01:55:33 -0700184}
185
Mel Gormanb44129b2011-01-13 15:45:43 -0800186void set_pgdat_percpu_threshold(pg_data_t *pgdat,
187 int (*calculate_pressure)(struct zone *))
Mel Gorman88f5acf2011-01-13 15:45:41 -0800188{
189 struct zone *zone;
190 int cpu;
191 int threshold;
192 int i;
193
Mel Gorman88f5acf2011-01-13 15:45:41 -0800194 for (i = 0; i < pgdat->nr_zones; i++) {
195 zone = &pgdat->node_zones[i];
196 if (!zone->percpu_drift_mark)
197 continue;
198
Mel Gormanb44129b2011-01-13 15:45:43 -0800199 threshold = (*calculate_pressure)(zone);
200 for_each_possible_cpu(cpu)
Mel Gorman88f5acf2011-01-13 15:45:41 -0800201 per_cpu_ptr(zone->pageset, cpu)->stat_threshold
202 = threshold;
203 }
Mel Gorman88f5acf2011-01-13 15:45:41 -0800204}
205
Christoph Lameter2244b952006-06-30 01:55:33 -0700206/*
207 * For use when we know that interrupts are disabled.
208 */
209void __mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
210 int delta)
211{
Christoph Lameter12938a92010-12-06 11:16:20 -0600212 struct per_cpu_pageset __percpu *pcp = zone->pageset;
213 s8 __percpu *p = pcp->vm_stat_diff + item;
Christoph Lameter2244b952006-06-30 01:55:33 -0700214 long x;
Christoph Lameter12938a92010-12-06 11:16:20 -0600215 long t;
Christoph Lameter2244b952006-06-30 01:55:33 -0700216
Christoph Lameter12938a92010-12-06 11:16:20 -0600217 x = delta + __this_cpu_read(*p);
Christoph Lameter2244b952006-06-30 01:55:33 -0700218
Christoph Lameter12938a92010-12-06 11:16:20 -0600219 t = __this_cpu_read(pcp->stat_threshold);
220
221 if (unlikely(x > t || x < -t)) {
Christoph Lameter2244b952006-06-30 01:55:33 -0700222 zone_page_state_add(x, zone, item);
223 x = 0;
224 }
Christoph Lameter12938a92010-12-06 11:16:20 -0600225 __this_cpu_write(*p, x);
Christoph Lameter2244b952006-06-30 01:55:33 -0700226}
227EXPORT_SYMBOL(__mod_zone_page_state);
228
229/*
Christoph Lameter2244b952006-06-30 01:55:33 -0700230 * Optimized increment and decrement functions.
231 *
232 * These are only for a single page and therefore can take a struct page *
233 * argument instead of struct zone *. This allows the inclusion of the code
234 * generated for page_zone(page) into the optimized functions.
235 *
236 * No overflow check is necessary and therefore the differential can be
237 * incremented or decremented in place which may allow the compilers to
238 * generate better code.
Christoph Lameter2244b952006-06-30 01:55:33 -0700239 * The increment or decrement is known and therefore one boundary check can
240 * be omitted.
241 *
Christoph Lameterdf9ecab2006-08-31 21:27:35 -0700242 * NOTE: These functions are very performance sensitive. Change only
243 * with care.
244 *
Christoph Lameter2244b952006-06-30 01:55:33 -0700245 * Some processors have inc/dec instructions that are atomic vs an interrupt.
246 * However, the code must first determine the differential location in a zone
247 * based on the processor number and then inc/dec the counter. There is no
248 * guarantee without disabling preemption that the processor will not change
249 * in between and therefore the atomicity vs. interrupt cannot be exploited
250 * in a useful way here.
251 */
Christoph Lameterc8785382007-02-10 01:43:01 -0800252void __inc_zone_state(struct zone *zone, enum zone_stat_item item)
Christoph Lameter2244b952006-06-30 01:55:33 -0700253{
Christoph Lameter12938a92010-12-06 11:16:20 -0600254 struct per_cpu_pageset __percpu *pcp = zone->pageset;
255 s8 __percpu *p = pcp->vm_stat_diff + item;
256 s8 v, t;
Christoph Lameter2244b952006-06-30 01:55:33 -0700257
Christoph Lameter908ee0f2010-12-06 11:40:02 -0600258 v = __this_cpu_inc_return(*p);
Christoph Lameter12938a92010-12-06 11:16:20 -0600259 t = __this_cpu_read(pcp->stat_threshold);
260 if (unlikely(v > t)) {
261 s8 overstep = t >> 1;
Christoph Lameter2244b952006-06-30 01:55:33 -0700262
Christoph Lameter12938a92010-12-06 11:16:20 -0600263 zone_page_state_add(v + overstep, zone, item);
264 __this_cpu_write(*p, -overstep);
Christoph Lameter2244b952006-06-30 01:55:33 -0700265 }
266}
Christoph Lameterca889e62006-06-30 01:55:44 -0700267
268void __inc_zone_page_state(struct page *page, enum zone_stat_item item)
269{
270 __inc_zone_state(page_zone(page), item);
271}
Christoph Lameter2244b952006-06-30 01:55:33 -0700272EXPORT_SYMBOL(__inc_zone_page_state);
273
Christoph Lameterc8785382007-02-10 01:43:01 -0800274void __dec_zone_state(struct zone *zone, enum zone_stat_item item)
Christoph Lameter2244b952006-06-30 01:55:33 -0700275{
Christoph Lameter12938a92010-12-06 11:16:20 -0600276 struct per_cpu_pageset __percpu *pcp = zone->pageset;
277 s8 __percpu *p = pcp->vm_stat_diff + item;
278 s8 v, t;
Christoph Lameter2244b952006-06-30 01:55:33 -0700279
Christoph Lameter908ee0f2010-12-06 11:40:02 -0600280 v = __this_cpu_dec_return(*p);
Christoph Lameter12938a92010-12-06 11:16:20 -0600281 t = __this_cpu_read(pcp->stat_threshold);
282 if (unlikely(v < - t)) {
283 s8 overstep = t >> 1;
Christoph Lameter2244b952006-06-30 01:55:33 -0700284
Christoph Lameter12938a92010-12-06 11:16:20 -0600285 zone_page_state_add(v - overstep, zone, item);
286 __this_cpu_write(*p, overstep);
Christoph Lameter2244b952006-06-30 01:55:33 -0700287 }
288}
Christoph Lameterc8785382007-02-10 01:43:01 -0800289
290void __dec_zone_page_state(struct page *page, enum zone_stat_item item)
291{
292 __dec_zone_state(page_zone(page), item);
293}
Christoph Lameter2244b952006-06-30 01:55:33 -0700294EXPORT_SYMBOL(__dec_zone_page_state);
295
Heiko Carstens41561532012-01-12 17:17:30 -0800296#ifdef CONFIG_HAVE_CMPXCHG_LOCAL
Christoph Lameter7c839122010-12-14 10:28:46 -0600297/*
298 * If we have cmpxchg_local support then we do not need to incur the overhead
299 * that comes with local_irq_save/restore if we use this_cpu_cmpxchg.
300 *
301 * mod_state() modifies the zone counter state through atomic per cpu
302 * operations.
303 *
304 * Overstep mode specifies how overstep should handled:
305 * 0 No overstepping
306 * 1 Overstepping half of threshold
307 * -1 Overstepping minus half of threshold
308*/
309static inline void mod_state(struct zone *zone,
310 enum zone_stat_item item, int delta, int overstep_mode)
311{
312 struct per_cpu_pageset __percpu *pcp = zone->pageset;
313 s8 __percpu *p = pcp->vm_stat_diff + item;
314 long o, n, t, z;
315
316 do {
317 z = 0; /* overflow to zone counters */
318
319 /*
320 * The fetching of the stat_threshold is racy. We may apply
321 * a counter threshold to the wrong the cpu if we get
Christoph Lameterd3bc2362011-04-14 15:21:58 -0700322 * rescheduled while executing here. However, the next
323 * counter update will apply the threshold again and
324 * therefore bring the counter under the threshold again.
325 *
326 * Most of the time the thresholds are the same anyways
327 * for all cpus in a zone.
Christoph Lameter7c839122010-12-14 10:28:46 -0600328 */
329 t = this_cpu_read(pcp->stat_threshold);
330
331 o = this_cpu_read(*p);
332 n = delta + o;
333
334 if (n > t || n < -t) {
335 int os = overstep_mode * (t >> 1) ;
336
337 /* Overflow must be added to zone counters */
338 z = n + os;
339 n = -os;
340 }
341 } while (this_cpu_cmpxchg(*p, o, n) != o);
342
343 if (z)
344 zone_page_state_add(z, zone, item);
345}
346
347void mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
348 int delta)
349{
350 mod_state(zone, item, delta, 0);
351}
352EXPORT_SYMBOL(mod_zone_page_state);
353
354void inc_zone_state(struct zone *zone, enum zone_stat_item item)
355{
356 mod_state(zone, item, 1, 1);
357}
358
359void inc_zone_page_state(struct page *page, enum zone_stat_item item)
360{
361 mod_state(page_zone(page), item, 1, 1);
362}
363EXPORT_SYMBOL(inc_zone_page_state);
364
365void dec_zone_page_state(struct page *page, enum zone_stat_item item)
366{
367 mod_state(page_zone(page), item, -1, -1);
368}
369EXPORT_SYMBOL(dec_zone_page_state);
370#else
371/*
372 * Use interrupt disable to serialize counter updates
373 */
374void mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
375 int delta)
376{
377 unsigned long flags;
378
379 local_irq_save(flags);
380 __mod_zone_page_state(zone, item, delta);
381 local_irq_restore(flags);
382}
383EXPORT_SYMBOL(mod_zone_page_state);
384
Christoph Lameterca889e62006-06-30 01:55:44 -0700385void inc_zone_state(struct zone *zone, enum zone_stat_item item)
386{
387 unsigned long flags;
388
389 local_irq_save(flags);
390 __inc_zone_state(zone, item);
391 local_irq_restore(flags);
392}
393
Christoph Lameter2244b952006-06-30 01:55:33 -0700394void inc_zone_page_state(struct page *page, enum zone_stat_item item)
395{
396 unsigned long flags;
397 struct zone *zone;
Christoph Lameter2244b952006-06-30 01:55:33 -0700398
399 zone = page_zone(page);
400 local_irq_save(flags);
Christoph Lameterca889e62006-06-30 01:55:44 -0700401 __inc_zone_state(zone, item);
Christoph Lameter2244b952006-06-30 01:55:33 -0700402 local_irq_restore(flags);
403}
404EXPORT_SYMBOL(inc_zone_page_state);
405
406void dec_zone_page_state(struct page *page, enum zone_stat_item item)
407{
408 unsigned long flags;
Christoph Lameter2244b952006-06-30 01:55:33 -0700409
Christoph Lameter2244b952006-06-30 01:55:33 -0700410 local_irq_save(flags);
Christoph Lametera302eb42006-08-31 21:27:34 -0700411 __dec_zone_page_state(page, item);
Christoph Lameter2244b952006-06-30 01:55:33 -0700412 local_irq_restore(flags);
413}
414EXPORT_SYMBOL(dec_zone_page_state);
Christoph Lameter7c839122010-12-14 10:28:46 -0600415#endif
Christoph Lameter2244b952006-06-30 01:55:33 -0700416
417/*
418 * Update the zone counters for one cpu.
Christoph Lameter4037d452007-05-09 02:35:14 -0700419 *
Christoph Lametera7f75e22008-02-04 22:29:16 -0800420 * The cpu specified must be either the current cpu or a processor that
421 * is not online. If it is the current cpu then the execution thread must
422 * be pinned to the current cpu.
423 *
Christoph Lameter4037d452007-05-09 02:35:14 -0700424 * Note that refresh_cpu_vm_stats strives to only access
425 * node local memory. The per cpu pagesets on remote zones are placed
426 * in the memory local to the processor using that pageset. So the
427 * loop over all zones will access a series of cachelines local to
428 * the processor.
429 *
430 * The call to zone_page_state_add updates the cachelines with the
431 * statistics in the remote zone struct as well as the global cachelines
432 * with the global counters. These could cause remote node cache line
433 * bouncing and will have to be only done when necessary.
Christoph Lameter2244b952006-06-30 01:55:33 -0700434 */
435void refresh_cpu_vm_stats(int cpu)
436{
437 struct zone *zone;
438 int i;
Christoph Lametera7f75e22008-02-04 22:29:16 -0800439 int global_diff[NR_VM_ZONE_STAT_ITEMS] = { 0, };
Christoph Lameter2244b952006-06-30 01:55:33 -0700440
KOSAKI Motohiroee99c712009-03-31 15:19:31 -0700441 for_each_populated_zone(zone) {
Christoph Lameter4037d452007-05-09 02:35:14 -0700442 struct per_cpu_pageset *p;
Christoph Lameter2244b952006-06-30 01:55:33 -0700443
Christoph Lameter99dcc3e2010-01-05 15:34:51 +0900444 p = per_cpu_ptr(zone->pageset, cpu);
Christoph Lameter2244b952006-06-30 01:55:33 -0700445
446 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
Christoph Lameter4037d452007-05-09 02:35:14 -0700447 if (p->vm_stat_diff[i]) {
Christoph Lametera7f75e22008-02-04 22:29:16 -0800448 unsigned long flags;
449 int v;
450
Christoph Lameter2244b952006-06-30 01:55:33 -0700451 local_irq_save(flags);
Christoph Lametera7f75e22008-02-04 22:29:16 -0800452 v = p->vm_stat_diff[i];
Christoph Lameter4037d452007-05-09 02:35:14 -0700453 p->vm_stat_diff[i] = 0;
Christoph Lametera7f75e22008-02-04 22:29:16 -0800454 local_irq_restore(flags);
455 atomic_long_add(v, &zone->vm_stat[i]);
456 global_diff[i] += v;
Christoph Lameter4037d452007-05-09 02:35:14 -0700457#ifdef CONFIG_NUMA
458 /* 3 seconds idle till flush */
459 p->expire = 3;
460#endif
Christoph Lameter2244b952006-06-30 01:55:33 -0700461 }
Dimitri Sivanich468fd622008-04-28 02:13:37 -0700462 cond_resched();
Christoph Lameter4037d452007-05-09 02:35:14 -0700463#ifdef CONFIG_NUMA
464 /*
465 * Deal with draining the remote pageset of this
466 * processor
467 *
468 * Check if there are pages remaining in this pageset
469 * if not then there is nothing to expire.
470 */
Christoph Lameter3dfa5722008-02-04 22:29:19 -0800471 if (!p->expire || !p->pcp.count)
Christoph Lameter4037d452007-05-09 02:35:14 -0700472 continue;
473
474 /*
475 * We never drain zones local to this processor.
476 */
477 if (zone_to_nid(zone) == numa_node_id()) {
478 p->expire = 0;
479 continue;
480 }
481
482 p->expire--;
483 if (p->expire)
484 continue;
485
Christoph Lameter3dfa5722008-02-04 22:29:19 -0800486 if (p->pcp.count)
487 drain_zone_pages(zone, &p->pcp);
Christoph Lameter4037d452007-05-09 02:35:14 -0700488#endif
Christoph Lameter2244b952006-06-30 01:55:33 -0700489 }
Christoph Lametera7f75e22008-02-04 22:29:16 -0800490
491 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
492 if (global_diff[i])
493 atomic_long_add(global_diff[i], &vm_stat[i]);
Christoph Lameter2244b952006-06-30 01:55:33 -0700494}
495
Cody P Schafer40f4b1e2013-04-29 15:08:38 -0700496/*
497 * this is only called if !populated_zone(zone), which implies no other users of
498 * pset->vm_stat_diff[] exsist.
499 */
Minchan Kim5a883812012-10-08 16:33:39 -0700500void drain_zonestat(struct zone *zone, struct per_cpu_pageset *pset)
501{
502 int i;
503
504 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
505 if (pset->vm_stat_diff[i]) {
506 int v = pset->vm_stat_diff[i];
507 pset->vm_stat_diff[i] = 0;
508 atomic_long_add(v, &zone->vm_stat[i]);
509 atomic_long_add(v, &vm_stat[i]);
510 }
511}
Christoph Lameter2244b952006-06-30 01:55:33 -0700512#endif
513
Christoph Lameterca889e62006-06-30 01:55:44 -0700514#ifdef CONFIG_NUMA
515/*
516 * zonelist = the list of zones passed to the allocator
517 * z = the zone from which the allocation occurred.
518 *
519 * Must be called with interrupts disabled.
Andi Kleen78afd562011-03-22 16:33:12 -0700520 *
521 * When __GFP_OTHER_NODE is set assume the node of the preferred
522 * zone is the local node. This is useful for daemons who allocate
523 * memory on behalf of other processes.
Christoph Lameterca889e62006-06-30 01:55:44 -0700524 */
Andi Kleen78afd562011-03-22 16:33:12 -0700525void zone_statistics(struct zone *preferred_zone, struct zone *z, gfp_t flags)
Christoph Lameterca889e62006-06-30 01:55:44 -0700526{
Mel Gorman18ea7e72008-04-28 02:12:14 -0700527 if (z->zone_pgdat == preferred_zone->zone_pgdat) {
Christoph Lameterca889e62006-06-30 01:55:44 -0700528 __inc_zone_state(z, NUMA_HIT);
529 } else {
530 __inc_zone_state(z, NUMA_MISS);
Mel Gorman18ea7e72008-04-28 02:12:14 -0700531 __inc_zone_state(preferred_zone, NUMA_FOREIGN);
Christoph Lameterca889e62006-06-30 01:55:44 -0700532 }
Andi Kleen78afd562011-03-22 16:33:12 -0700533 if (z->node == ((flags & __GFP_OTHER_NODE) ?
534 preferred_zone->node : numa_node_id()))
Christoph Lameterca889e62006-06-30 01:55:44 -0700535 __inc_zone_state(z, NUMA_LOCAL);
536 else
537 __inc_zone_state(z, NUMA_OTHER);
538}
539#endif
540
Mel Gormand7a57522010-05-24 14:32:25 -0700541#ifdef CONFIG_COMPACTION
Namhyung Kim36deb0b2010-10-26 14:22:04 -0700542
Mel Gormand7a57522010-05-24 14:32:25 -0700543struct contig_page_info {
544 unsigned long free_pages;
545 unsigned long free_blocks_total;
546 unsigned long free_blocks_suitable;
547};
548
549/*
550 * Calculate the number of free pages in a zone, how many contiguous
551 * pages are free and how many are large enough to satisfy an allocation of
552 * the target size. Note that this function makes no attempt to estimate
553 * how many suitable free blocks there *might* be if MOVABLE pages were
554 * migrated. Calculating that is possible, but expensive and can be
555 * figured out from userspace
556 */
557static void fill_contig_page_info(struct zone *zone,
558 unsigned int suitable_order,
559 struct contig_page_info *info)
560{
561 unsigned int order;
562
563 info->free_pages = 0;
564 info->free_blocks_total = 0;
565 info->free_blocks_suitable = 0;
566
567 for (order = 0; order < MAX_ORDER; order++) {
568 unsigned long blocks;
569
570 /* Count number of free blocks */
571 blocks = zone->free_area[order].nr_free;
572 info->free_blocks_total += blocks;
573
574 /* Count free base pages */
575 info->free_pages += blocks << order;
576
577 /* Count the suitable free blocks */
578 if (order >= suitable_order)
579 info->free_blocks_suitable += blocks <<
580 (order - suitable_order);
581 }
582}
Mel Gormanf1a5ab12010-05-24 14:32:26 -0700583
584/*
585 * A fragmentation index only makes sense if an allocation of a requested
586 * size would fail. If that is true, the fragmentation index indicates
587 * whether external fragmentation or a lack of memory was the problem.
588 * The value can be used to determine if page reclaim or compaction
589 * should be used
590 */
Mel Gorman56de7262010-05-24 14:32:30 -0700591static int __fragmentation_index(unsigned int order, struct contig_page_info *info)
Mel Gormanf1a5ab12010-05-24 14:32:26 -0700592{
593 unsigned long requested = 1UL << order;
594
595 if (!info->free_blocks_total)
596 return 0;
597
598 /* Fragmentation index only makes sense when a request would fail */
599 if (info->free_blocks_suitable)
600 return -1000;
601
602 /*
603 * Index is between 0 and 1 so return within 3 decimal places
604 *
605 * 0 => allocation would fail due to lack of memory
606 * 1 => allocation would fail due to fragmentation
607 */
608 return 1000 - div_u64( (1000+(div_u64(info->free_pages * 1000ULL, requested))), info->free_blocks_total);
609}
Mel Gorman56de7262010-05-24 14:32:30 -0700610
611/* Same as __fragmentation index but allocs contig_page_info on stack */
612int fragmentation_index(struct zone *zone, unsigned int order)
613{
614 struct contig_page_info info;
615
616 fill_contig_page_info(zone, order, &info);
617 return __fragmentation_index(order, &info);
618}
Mel Gormand7a57522010-05-24 14:32:25 -0700619#endif
620
621#if defined(CONFIG_PROC_FS) || defined(CONFIG_COMPACTION)
Alexey Dobriyan8f32f7e2008-10-06 04:13:52 +0400622#include <linux/proc_fs.h>
Christoph Lameterf6ac2352006-06-30 01:55:32 -0700623#include <linux/seq_file.h>
624
Mel Gorman467c9962007-10-16 01:26:02 -0700625static char * const migratetype_names[MIGRATE_TYPES] = {
626 "Unmovable",
627 "Reclaimable",
628 "Movable",
629 "Reserve",
Michal Nazarewicz47118af2011-12-29 13:09:50 +0100630#ifdef CONFIG_CMA
631 "CMA",
632#endif
Minchan Kim194159f2013-02-22 16:33:58 -0800633#ifdef CONFIG_MEMORY_ISOLATION
KOSAKI Motohiro91446b02008-04-15 14:34:42 -0700634 "Isolate",
Minchan Kim194159f2013-02-22 16:33:58 -0800635#endif
Mel Gorman467c9962007-10-16 01:26:02 -0700636};
637
Christoph Lameterf6ac2352006-06-30 01:55:32 -0700638static void *frag_start(struct seq_file *m, loff_t *pos)
639{
640 pg_data_t *pgdat;
641 loff_t node = *pos;
642 for (pgdat = first_online_pgdat();
643 pgdat && node;
644 pgdat = next_online_pgdat(pgdat))
645 --node;
646
647 return pgdat;
648}
649
650static void *frag_next(struct seq_file *m, void *arg, loff_t *pos)
651{
652 pg_data_t *pgdat = (pg_data_t *)arg;
653
654 (*pos)++;
655 return next_online_pgdat(pgdat);
656}
657
658static void frag_stop(struct seq_file *m, void *arg)
659{
660}
661
Mel Gorman467c9962007-10-16 01:26:02 -0700662/* Walk all the zones in a node and print using a callback */
663static void walk_zones_in_node(struct seq_file *m, pg_data_t *pgdat,
664 void (*print)(struct seq_file *m, pg_data_t *, struct zone *))
Christoph Lameterf6ac2352006-06-30 01:55:32 -0700665{
Christoph Lameterf6ac2352006-06-30 01:55:32 -0700666 struct zone *zone;
667 struct zone *node_zones = pgdat->node_zones;
668 unsigned long flags;
Christoph Lameterf6ac2352006-06-30 01:55:32 -0700669
670 for (zone = node_zones; zone - node_zones < MAX_NR_ZONES; ++zone) {
671 if (!populated_zone(zone))
672 continue;
673
674 spin_lock_irqsave(&zone->lock, flags);
Mel Gorman467c9962007-10-16 01:26:02 -0700675 print(m, pgdat, zone);
Christoph Lameterf6ac2352006-06-30 01:55:32 -0700676 spin_unlock_irqrestore(&zone->lock, flags);
Mel Gorman467c9962007-10-16 01:26:02 -0700677 }
678}
Mel Gormand7a57522010-05-24 14:32:25 -0700679#endif
Mel Gorman467c9962007-10-16 01:26:02 -0700680
David Rientjes0d6617c2011-09-14 16:21:05 -0700681#if defined(CONFIG_PROC_FS) || defined(CONFIG_SYSFS) || defined(CONFIG_NUMA)
KOSAKI Motohirofa25c502011-05-24 17:11:28 -0700682#ifdef CONFIG_ZONE_DMA
683#define TEXT_FOR_DMA(xx) xx "_dma",
684#else
685#define TEXT_FOR_DMA(xx)
686#endif
687
688#ifdef CONFIG_ZONE_DMA32
689#define TEXT_FOR_DMA32(xx) xx "_dma32",
690#else
691#define TEXT_FOR_DMA32(xx)
692#endif
693
694#ifdef CONFIG_HIGHMEM
695#define TEXT_FOR_HIGHMEM(xx) xx "_high",
696#else
697#define TEXT_FOR_HIGHMEM(xx)
698#endif
699
700#define TEXTS_FOR_ZONES(xx) TEXT_FOR_DMA(xx) TEXT_FOR_DMA32(xx) xx "_normal", \
701 TEXT_FOR_HIGHMEM(xx) xx "_movable",
702
703const char * const vmstat_text[] = {
704 /* Zoned VM counters */
705 "nr_free_pages",
706 "nr_inactive_anon",
707 "nr_active_anon",
708 "nr_inactive_file",
709 "nr_active_file",
710 "nr_unevictable",
711 "nr_mlock",
712 "nr_anon_pages",
713 "nr_mapped",
714 "nr_file_pages",
715 "nr_dirty",
716 "nr_writeback",
717 "nr_slab_reclaimable",
718 "nr_slab_unreclaimable",
719 "nr_page_table_pages",
720 "nr_kernel_stack",
721 "nr_unstable",
722 "nr_bounce",
723 "nr_vmscan_write",
Mel Gorman49ea7eb2011-10-31 17:07:59 -0700724 "nr_vmscan_immediate_reclaim",
KOSAKI Motohirofa25c502011-05-24 17:11:28 -0700725 "nr_writeback_temp",
726 "nr_isolated_anon",
727 "nr_isolated_file",
728 "nr_shmem",
729 "nr_dirtied",
730 "nr_written",
731
732#ifdef CONFIG_NUMA
733 "numa_hit",
734 "numa_miss",
735 "numa_foreign",
736 "numa_interleave",
737 "numa_local",
738 "numa_other",
739#endif
740 "nr_anon_transparent_hugepages",
Bartlomiej Zolnierkiewiczd1ce7492012-10-08 16:32:02 -0700741 "nr_free_cma",
KOSAKI Motohirofa25c502011-05-24 17:11:28 -0700742 "nr_dirty_threshold",
743 "nr_dirty_background_threshold",
744
745#ifdef CONFIG_VM_EVENT_COUNTERS
746 "pgpgin",
747 "pgpgout",
748 "pswpin",
749 "pswpout",
750
751 TEXTS_FOR_ZONES("pgalloc")
752
753 "pgfree",
754 "pgactivate",
755 "pgdeactivate",
756
757 "pgfault",
758 "pgmajfault",
759
760 TEXTS_FOR_ZONES("pgrefill")
Ying Han904249a2012-04-25 16:01:48 -0700761 TEXTS_FOR_ZONES("pgsteal_kswapd")
762 TEXTS_FOR_ZONES("pgsteal_direct")
KOSAKI Motohirofa25c502011-05-24 17:11:28 -0700763 TEXTS_FOR_ZONES("pgscan_kswapd")
764 TEXTS_FOR_ZONES("pgscan_direct")
Mel Gorman68243e72012-07-31 16:44:39 -0700765 "pgscan_direct_throttle",
KOSAKI Motohirofa25c502011-05-24 17:11:28 -0700766
767#ifdef CONFIG_NUMA
768 "zone_reclaim_failed",
769#endif
770 "pginodesteal",
771 "slabs_scanned",
KOSAKI Motohirofa25c502011-05-24 17:11:28 -0700772 "kswapd_inodesteal",
773 "kswapd_low_wmark_hit_quickly",
774 "kswapd_high_wmark_hit_quickly",
KOSAKI Motohirofa25c502011-05-24 17:11:28 -0700775 "pageoutrun",
776 "allocstall",
777
778 "pgrotated",
779
Mel Gorman03c5a6e2012-11-02 14:52:48 +0000780#ifdef CONFIG_NUMA_BALANCING
781 "numa_pte_updates",
782 "numa_hint_faults",
783 "numa_hint_faults_local",
784 "numa_pages_migrated",
785#endif
Mel Gorman5647bc22012-10-19 10:46:20 +0100786#ifdef CONFIG_MIGRATION
787 "pgmigrate_success",
788 "pgmigrate_fail",
789#endif
KOSAKI Motohirofa25c502011-05-24 17:11:28 -0700790#ifdef CONFIG_COMPACTION
Mel Gorman397487d2012-10-19 12:00:10 +0100791 "compact_migrate_scanned",
792 "compact_free_scanned",
793 "compact_isolated",
KOSAKI Motohirofa25c502011-05-24 17:11:28 -0700794 "compact_stall",
795 "compact_fail",
796 "compact_success",
797#endif
798
799#ifdef CONFIG_HUGETLB_PAGE
800 "htlb_buddy_alloc_success",
801 "htlb_buddy_alloc_fail",
802#endif
803 "unevictable_pgs_culled",
804 "unevictable_pgs_scanned",
805 "unevictable_pgs_rescued",
806 "unevictable_pgs_mlocked",
807 "unevictable_pgs_munlocked",
808 "unevictable_pgs_cleared",
809 "unevictable_pgs_stranded",
KOSAKI Motohirofa25c502011-05-24 17:11:28 -0700810
811#ifdef CONFIG_TRANSPARENT_HUGEPAGE
812 "thp_fault_alloc",
813 "thp_fault_fallback",
814 "thp_collapse_alloc",
815 "thp_collapse_alloc_failed",
816 "thp_split",
Kirill A. Shutemovd8a8e1f2012-12-12 13:51:09 -0800817 "thp_zero_page_alloc",
818 "thp_zero_page_alloc_failed",
KOSAKI Motohirofa25c502011-05-24 17:11:28 -0700819#endif
820
821#endif /* CONFIG_VM_EVENTS_COUNTERS */
822};
David Rientjes0d6617c2011-09-14 16:21:05 -0700823#endif /* CONFIG_PROC_FS || CONFIG_SYSFS || CONFIG_NUMA */
KOSAKI Motohirofa25c502011-05-24 17:11:28 -0700824
825
Mel Gormand7a57522010-05-24 14:32:25 -0700826#ifdef CONFIG_PROC_FS
Mel Gorman467c9962007-10-16 01:26:02 -0700827static void frag_show_print(struct seq_file *m, pg_data_t *pgdat,
828 struct zone *zone)
829{
830 int order;
831
832 seq_printf(m, "Node %d, zone %8s ", pgdat->node_id, zone->name);
833 for (order = 0; order < MAX_ORDER; ++order)
834 seq_printf(m, "%6lu ", zone->free_area[order].nr_free);
835 seq_putc(m, '\n');
836}
837
838/*
839 * This walks the free areas for each zone.
840 */
841static int frag_show(struct seq_file *m, void *arg)
842{
843 pg_data_t *pgdat = (pg_data_t *)arg;
844 walk_zones_in_node(m, pgdat, frag_show_print);
845 return 0;
846}
847
848static void pagetypeinfo_showfree_print(struct seq_file *m,
849 pg_data_t *pgdat, struct zone *zone)
850{
851 int order, mtype;
852
853 for (mtype = 0; mtype < MIGRATE_TYPES; mtype++) {
854 seq_printf(m, "Node %4d, zone %8s, type %12s ",
855 pgdat->node_id,
856 zone->name,
857 migratetype_names[mtype]);
858 for (order = 0; order < MAX_ORDER; ++order) {
859 unsigned long freecount = 0;
860 struct free_area *area;
861 struct list_head *curr;
862
863 area = &(zone->free_area[order]);
864
865 list_for_each(curr, &area->free_list[mtype])
866 freecount++;
867 seq_printf(m, "%6lu ", freecount);
868 }
Christoph Lameterf6ac2352006-06-30 01:55:32 -0700869 seq_putc(m, '\n');
870 }
Mel Gorman467c9962007-10-16 01:26:02 -0700871}
872
873/* Print out the free pages at each order for each migatetype */
874static int pagetypeinfo_showfree(struct seq_file *m, void *arg)
875{
876 int order;
877 pg_data_t *pgdat = (pg_data_t *)arg;
878
879 /* Print header */
880 seq_printf(m, "%-43s ", "Free pages count per migrate type at order");
881 for (order = 0; order < MAX_ORDER; ++order)
882 seq_printf(m, "%6d ", order);
883 seq_putc(m, '\n');
884
885 walk_zones_in_node(m, pgdat, pagetypeinfo_showfree_print);
886
887 return 0;
888}
889
890static void pagetypeinfo_showblockcount_print(struct seq_file *m,
891 pg_data_t *pgdat, struct zone *zone)
892{
893 int mtype;
894 unsigned long pfn;
895 unsigned long start_pfn = zone->zone_start_pfn;
Cody P Schafer108bcc92013-02-22 16:35:23 -0800896 unsigned long end_pfn = zone_end_pfn(zone);
Mel Gorman467c9962007-10-16 01:26:02 -0700897 unsigned long count[MIGRATE_TYPES] = { 0, };
898
899 for (pfn = start_pfn; pfn < end_pfn; pfn += pageblock_nr_pages) {
900 struct page *page;
901
902 if (!pfn_valid(pfn))
903 continue;
904
905 page = pfn_to_page(pfn);
Mel Gormaneb335752009-05-13 17:34:48 +0100906
907 /* Watch for unexpected holes punched in the memmap */
908 if (!memmap_valid_within(pfn, page, zone))
Mel Gormane80d6a22008-08-14 11:10:14 +0100909 continue;
Mel Gormaneb335752009-05-13 17:34:48 +0100910
Mel Gorman467c9962007-10-16 01:26:02 -0700911 mtype = get_pageblock_migratetype(page);
912
Mel Gormane80d6a22008-08-14 11:10:14 +0100913 if (mtype < MIGRATE_TYPES)
914 count[mtype]++;
Mel Gorman467c9962007-10-16 01:26:02 -0700915 }
916
917 /* Print counts */
918 seq_printf(m, "Node %d, zone %8s ", pgdat->node_id, zone->name);
919 for (mtype = 0; mtype < MIGRATE_TYPES; mtype++)
920 seq_printf(m, "%12lu ", count[mtype]);
921 seq_putc(m, '\n');
922}
923
924/* Print out the free pages at each order for each migratetype */
925static int pagetypeinfo_showblockcount(struct seq_file *m, void *arg)
926{
927 int mtype;
928 pg_data_t *pgdat = (pg_data_t *)arg;
929
930 seq_printf(m, "\n%-23s", "Number of blocks type ");
931 for (mtype = 0; mtype < MIGRATE_TYPES; mtype++)
932 seq_printf(m, "%12s ", migratetype_names[mtype]);
933 seq_putc(m, '\n');
934 walk_zones_in_node(m, pgdat, pagetypeinfo_showblockcount_print);
935
936 return 0;
937}
938
939/*
940 * This prints out statistics in relation to grouping pages by mobility.
941 * It is expensive to collect so do not constantly read the file.
942 */
943static int pagetypeinfo_show(struct seq_file *m, void *arg)
944{
945 pg_data_t *pgdat = (pg_data_t *)arg;
946
KOSAKI Motohiro41b25a32008-04-30 00:52:13 -0700947 /* check memoryless node */
Lai Jiangshana47b53c2012-12-12 13:51:37 -0800948 if (!node_state(pgdat->node_id, N_MEMORY))
KOSAKI Motohiro41b25a32008-04-30 00:52:13 -0700949 return 0;
950
Mel Gorman467c9962007-10-16 01:26:02 -0700951 seq_printf(m, "Page block order: %d\n", pageblock_order);
952 seq_printf(m, "Pages per block: %lu\n", pageblock_nr_pages);
953 seq_putc(m, '\n');
954 pagetypeinfo_showfree(m, pgdat);
955 pagetypeinfo_showblockcount(m, pgdat);
956
Christoph Lameterf6ac2352006-06-30 01:55:32 -0700957 return 0;
958}
959
Alexey Dobriyan8f32f7e2008-10-06 04:13:52 +0400960static const struct seq_operations fragmentation_op = {
Christoph Lameterf6ac2352006-06-30 01:55:32 -0700961 .start = frag_start,
962 .next = frag_next,
963 .stop = frag_stop,
964 .show = frag_show,
965};
966
Alexey Dobriyan8f32f7e2008-10-06 04:13:52 +0400967static int fragmentation_open(struct inode *inode, struct file *file)
968{
969 return seq_open(file, &fragmentation_op);
970}
971
972static const struct file_operations fragmentation_file_operations = {
973 .open = fragmentation_open,
974 .read = seq_read,
975 .llseek = seq_lseek,
976 .release = seq_release,
977};
978
Alexey Dobriyan74e2e8e2008-10-06 04:15:36 +0400979static const struct seq_operations pagetypeinfo_op = {
Mel Gorman467c9962007-10-16 01:26:02 -0700980 .start = frag_start,
981 .next = frag_next,
982 .stop = frag_stop,
983 .show = pagetypeinfo_show,
984};
985
Alexey Dobriyan74e2e8e2008-10-06 04:15:36 +0400986static int pagetypeinfo_open(struct inode *inode, struct file *file)
987{
988 return seq_open(file, &pagetypeinfo_op);
989}
990
991static const struct file_operations pagetypeinfo_file_ops = {
992 .open = pagetypeinfo_open,
993 .read = seq_read,
994 .llseek = seq_lseek,
995 .release = seq_release,
996};
997
Mel Gorman467c9962007-10-16 01:26:02 -0700998static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat,
999 struct zone *zone)
1000{
1001 int i;
1002 seq_printf(m, "Node %d, zone %8s", pgdat->node_id, zone->name);
1003 seq_printf(m,
1004 "\n pages free %lu"
1005 "\n min %lu"
1006 "\n low %lu"
1007 "\n high %lu"
Wu Fengguang08d9ae72009-06-16 15:32:30 -07001008 "\n scanned %lu"
Mel Gorman467c9962007-10-16 01:26:02 -07001009 "\n spanned %lu"
Jiang Liu9feedc92012-12-12 13:52:12 -08001010 "\n present %lu"
1011 "\n managed %lu",
Mel Gorman88f5acf2011-01-13 15:45:41 -08001012 zone_page_state(zone, NR_FREE_PAGES),
Mel Gorman41858962009-06-16 15:32:12 -07001013 min_wmark_pages(zone),
1014 low_wmark_pages(zone),
1015 high_wmark_pages(zone),
Mel Gorman467c9962007-10-16 01:26:02 -07001016 zone->pages_scanned,
Mel Gorman467c9962007-10-16 01:26:02 -07001017 zone->spanned_pages,
Jiang Liu9feedc92012-12-12 13:52:12 -08001018 zone->present_pages,
1019 zone->managed_pages);
Mel Gorman467c9962007-10-16 01:26:02 -07001020
1021 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
1022 seq_printf(m, "\n %-12s %lu", vmstat_text[i],
1023 zone_page_state(zone, i));
1024
1025 seq_printf(m,
1026 "\n protection: (%lu",
1027 zone->lowmem_reserve[0]);
1028 for (i = 1; i < ARRAY_SIZE(zone->lowmem_reserve); i++)
1029 seq_printf(m, ", %lu", zone->lowmem_reserve[i]);
1030 seq_printf(m,
1031 ")"
1032 "\n pagesets");
1033 for_each_online_cpu(i) {
1034 struct per_cpu_pageset *pageset;
Mel Gorman467c9962007-10-16 01:26:02 -07001035
Christoph Lameter99dcc3e2010-01-05 15:34:51 +09001036 pageset = per_cpu_ptr(zone->pageset, i);
Christoph Lameter3dfa5722008-02-04 22:29:19 -08001037 seq_printf(m,
1038 "\n cpu: %i"
1039 "\n count: %i"
1040 "\n high: %i"
1041 "\n batch: %i",
1042 i,
1043 pageset->pcp.count,
1044 pageset->pcp.high,
1045 pageset->pcp.batch);
Mel Gorman467c9962007-10-16 01:26:02 -07001046#ifdef CONFIG_SMP
1047 seq_printf(m, "\n vm stats threshold: %d",
1048 pageset->stat_threshold);
1049#endif
1050 }
1051 seq_printf(m,
1052 "\n all_unreclaimable: %u"
Rik van Riel556adec2008-10-18 20:26:34 -07001053 "\n start_pfn: %lu"
1054 "\n inactive_ratio: %u",
KOSAKI Motohiro93e4a892010-03-05 13:41:55 -08001055 zone->all_unreclaimable,
Rik van Riel556adec2008-10-18 20:26:34 -07001056 zone->zone_start_pfn,
1057 zone->inactive_ratio);
Mel Gorman467c9962007-10-16 01:26:02 -07001058 seq_putc(m, '\n');
1059}
1060
Christoph Lameterf6ac2352006-06-30 01:55:32 -07001061/*
1062 * Output information about zones in @pgdat.
1063 */
1064static int zoneinfo_show(struct seq_file *m, void *arg)
1065{
Mel Gorman467c9962007-10-16 01:26:02 -07001066 pg_data_t *pgdat = (pg_data_t *)arg;
1067 walk_zones_in_node(m, pgdat, zoneinfo_show_print);
Christoph Lameterf6ac2352006-06-30 01:55:32 -07001068 return 0;
1069}
1070
Alexey Dobriyan5c9fe622008-10-06 04:19:42 +04001071static const struct seq_operations zoneinfo_op = {
Christoph Lameterf6ac2352006-06-30 01:55:32 -07001072 .start = frag_start, /* iterate over all zones. The same as in
1073 * fragmentation. */
1074 .next = frag_next,
1075 .stop = frag_stop,
1076 .show = zoneinfo_show,
1077};
1078
Alexey Dobriyan5c9fe622008-10-06 04:19:42 +04001079static int zoneinfo_open(struct inode *inode, struct file *file)
1080{
1081 return seq_open(file, &zoneinfo_op);
1082}
1083
1084static const struct file_operations proc_zoneinfo_file_operations = {
1085 .open = zoneinfo_open,
1086 .read = seq_read,
1087 .llseek = seq_lseek,
1088 .release = seq_release,
1089};
1090
Michael Rubin79da8262010-10-26 14:21:36 -07001091enum writeback_stat_item {
1092 NR_DIRTY_THRESHOLD,
1093 NR_DIRTY_BG_THRESHOLD,
1094 NR_VM_WRITEBACK_STAT_ITEMS,
1095};
1096
Christoph Lameterf6ac2352006-06-30 01:55:32 -07001097static void *vmstat_start(struct seq_file *m, loff_t *pos)
1098{
Christoph Lameter2244b952006-06-30 01:55:33 -07001099 unsigned long *v;
Michael Rubin79da8262010-10-26 14:21:36 -07001100 int i, stat_items_size;
Christoph Lameterf6ac2352006-06-30 01:55:32 -07001101
1102 if (*pos >= ARRAY_SIZE(vmstat_text))
1103 return NULL;
Michael Rubin79da8262010-10-26 14:21:36 -07001104 stat_items_size = NR_VM_ZONE_STAT_ITEMS * sizeof(unsigned long) +
1105 NR_VM_WRITEBACK_STAT_ITEMS * sizeof(unsigned long);
Christoph Lameterf6ac2352006-06-30 01:55:32 -07001106
Christoph Lameterf8891e52006-06-30 01:55:45 -07001107#ifdef CONFIG_VM_EVENT_COUNTERS
Michael Rubin79da8262010-10-26 14:21:36 -07001108 stat_items_size += sizeof(struct vm_event_state);
Christoph Lameterf8891e52006-06-30 01:55:45 -07001109#endif
Michael Rubin79da8262010-10-26 14:21:36 -07001110
1111 v = kmalloc(stat_items_size, GFP_KERNEL);
Christoph Lameter2244b952006-06-30 01:55:33 -07001112 m->private = v;
1113 if (!v)
Christoph Lameterf6ac2352006-06-30 01:55:32 -07001114 return ERR_PTR(-ENOMEM);
Christoph Lameter2244b952006-06-30 01:55:33 -07001115 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
1116 v[i] = global_page_state(i);
Michael Rubin79da8262010-10-26 14:21:36 -07001117 v += NR_VM_ZONE_STAT_ITEMS;
1118
1119 global_dirty_limits(v + NR_DIRTY_BG_THRESHOLD,
1120 v + NR_DIRTY_THRESHOLD);
1121 v += NR_VM_WRITEBACK_STAT_ITEMS;
1122
Christoph Lameterf8891e52006-06-30 01:55:45 -07001123#ifdef CONFIG_VM_EVENT_COUNTERS
Michael Rubin79da8262010-10-26 14:21:36 -07001124 all_vm_events(v);
1125 v[PGPGIN] /= 2; /* sectors -> kbytes */
1126 v[PGPGOUT] /= 2;
Christoph Lameterf8891e52006-06-30 01:55:45 -07001127#endif
Wu Fengguangff8b16d2010-11-04 01:56:49 +08001128 return (unsigned long *)m->private + *pos;
Christoph Lameterf6ac2352006-06-30 01:55:32 -07001129}
1130
1131static void *vmstat_next(struct seq_file *m, void *arg, loff_t *pos)
1132{
1133 (*pos)++;
1134 if (*pos >= ARRAY_SIZE(vmstat_text))
1135 return NULL;
1136 return (unsigned long *)m->private + *pos;
1137}
1138
1139static int vmstat_show(struct seq_file *m, void *arg)
1140{
1141 unsigned long *l = arg;
1142 unsigned long off = l - (unsigned long *)m->private;
1143
1144 seq_printf(m, "%s %lu\n", vmstat_text[off], *l);
1145 return 0;
1146}
1147
1148static void vmstat_stop(struct seq_file *m, void *arg)
1149{
1150 kfree(m->private);
1151 m->private = NULL;
1152}
1153
Alexey Dobriyanb6aa44a2008-10-06 04:17:48 +04001154static const struct seq_operations vmstat_op = {
Christoph Lameterf6ac2352006-06-30 01:55:32 -07001155 .start = vmstat_start,
1156 .next = vmstat_next,
1157 .stop = vmstat_stop,
1158 .show = vmstat_show,
1159};
1160
Alexey Dobriyanb6aa44a2008-10-06 04:17:48 +04001161static int vmstat_open(struct inode *inode, struct file *file)
1162{
1163 return seq_open(file, &vmstat_op);
1164}
1165
1166static const struct file_operations proc_vmstat_file_operations = {
1167 .open = vmstat_open,
1168 .read = seq_read,
1169 .llseek = seq_lseek,
1170 .release = seq_release,
1171};
Christoph Lameterf6ac2352006-06-30 01:55:32 -07001172#endif /* CONFIG_PROC_FS */
1173
Christoph Lameterdf9ecab2006-08-31 21:27:35 -07001174#ifdef CONFIG_SMP
Christoph Lameterd1187ed2007-05-09 02:35:12 -07001175static DEFINE_PER_CPU(struct delayed_work, vmstat_work);
Christoph Lameter77461ab2007-05-09 02:35:13 -07001176int sysctl_stat_interval __read_mostly = HZ;
Christoph Lameterd1187ed2007-05-09 02:35:12 -07001177
1178static void vmstat_update(struct work_struct *w)
1179{
1180 refresh_cpu_vm_stats(smp_processor_id());
Christoph Lameter77461ab2007-05-09 02:35:13 -07001181 schedule_delayed_work(&__get_cpu_var(vmstat_work),
Anton Blanchard98f4ebb2009-04-02 16:56:39 -07001182 round_jiffies_relative(sysctl_stat_interval));
Christoph Lameterd1187ed2007-05-09 02:35:12 -07001183}
1184
Randy Dunlap42614fc2007-11-14 17:00:12 -08001185static void __cpuinit start_cpu_timer(int cpu)
Christoph Lameterd1187ed2007-05-09 02:35:12 -07001186{
Tejun Heo1871e522009-10-29 22:34:13 +09001187 struct delayed_work *work = &per_cpu(vmstat_work, cpu);
Christoph Lameterd1187ed2007-05-09 02:35:12 -07001188
Tejun Heo203b42f2012-08-21 13:18:23 -07001189 INIT_DEFERRABLE_WORK(work, vmstat_update);
Tejun Heo1871e522009-10-29 22:34:13 +09001190 schedule_delayed_work_on(cpu, work, __round_jiffies_relative(HZ, cpu));
Christoph Lameterd1187ed2007-05-09 02:35:12 -07001191}
1192
Christoph Lameterdf9ecab2006-08-31 21:27:35 -07001193/*
1194 * Use the cpu notifier to insure that the thresholds are recalculated
1195 * when necessary.
1196 */
1197static int __cpuinit vmstat_cpuup_callback(struct notifier_block *nfb,
1198 unsigned long action,
1199 void *hcpu)
1200{
Christoph Lameterd1187ed2007-05-09 02:35:12 -07001201 long cpu = (long)hcpu;
1202
Christoph Lameterdf9ecab2006-08-31 21:27:35 -07001203 switch (action) {
Christoph Lameterd1187ed2007-05-09 02:35:12 -07001204 case CPU_ONLINE:
1205 case CPU_ONLINE_FROZEN:
KAMEZAWA Hiroyuki5ee28a42010-09-09 16:38:14 -07001206 refresh_zone_stat_thresholds();
Christoph Lameterd1187ed2007-05-09 02:35:12 -07001207 start_cpu_timer(cpu);
Christoph Lameterad596922010-01-05 15:34:51 +09001208 node_set_state(cpu_to_node(cpu), N_CPU);
Christoph Lameterd1187ed2007-05-09 02:35:12 -07001209 break;
1210 case CPU_DOWN_PREPARE:
1211 case CPU_DOWN_PREPARE_FROZEN:
Tejun Heoafe2c512010-12-14 16:21:17 +01001212 cancel_delayed_work_sync(&per_cpu(vmstat_work, cpu));
Christoph Lameterd1187ed2007-05-09 02:35:12 -07001213 per_cpu(vmstat_work, cpu).work.func = NULL;
1214 break;
1215 case CPU_DOWN_FAILED:
1216 case CPU_DOWN_FAILED_FROZEN:
1217 start_cpu_timer(cpu);
1218 break;
Andy Whitcroftce421c72006-12-06 20:33:08 -08001219 case CPU_DEAD:
Rafael J. Wysocki8bb78442007-05-09 02:35:10 -07001220 case CPU_DEAD_FROZEN:
Andy Whitcroftce421c72006-12-06 20:33:08 -08001221 refresh_zone_stat_thresholds();
1222 break;
1223 default:
1224 break;
Christoph Lameterdf9ecab2006-08-31 21:27:35 -07001225 }
1226 return NOTIFY_OK;
1227}
1228
1229static struct notifier_block __cpuinitdata vmstat_notifier =
1230 { &vmstat_cpuup_callback, NULL, 0 };
Alexey Dobriyan8f32f7e2008-10-06 04:13:52 +04001231#endif
Christoph Lameterdf9ecab2006-08-31 21:27:35 -07001232
Adrian Bunke2fc88d2007-10-16 01:26:27 -07001233static int __init setup_vmstat(void)
Christoph Lameterdf9ecab2006-08-31 21:27:35 -07001234{
Alexey Dobriyan8f32f7e2008-10-06 04:13:52 +04001235#ifdef CONFIG_SMP
Christoph Lameterd1187ed2007-05-09 02:35:12 -07001236 int cpu;
1237
Christoph Lameterdf9ecab2006-08-31 21:27:35 -07001238 register_cpu_notifier(&vmstat_notifier);
Christoph Lameterd1187ed2007-05-09 02:35:12 -07001239
1240 for_each_online_cpu(cpu)
1241 start_cpu_timer(cpu);
Alexey Dobriyan8f32f7e2008-10-06 04:13:52 +04001242#endif
1243#ifdef CONFIG_PROC_FS
1244 proc_create("buddyinfo", S_IRUGO, NULL, &fragmentation_file_operations);
Alexey Dobriyan74e2e8e2008-10-06 04:15:36 +04001245 proc_create("pagetypeinfo", S_IRUGO, NULL, &pagetypeinfo_file_ops);
Alexey Dobriyanb6aa44a2008-10-06 04:17:48 +04001246 proc_create("vmstat", S_IRUGO, NULL, &proc_vmstat_file_operations);
Alexey Dobriyan5c9fe622008-10-06 04:19:42 +04001247 proc_create("zoneinfo", S_IRUGO, NULL, &proc_zoneinfo_file_operations);
Alexey Dobriyan8f32f7e2008-10-06 04:13:52 +04001248#endif
Christoph Lameterdf9ecab2006-08-31 21:27:35 -07001249 return 0;
1250}
1251module_init(setup_vmstat)
Mel Gormand7a57522010-05-24 14:32:25 -07001252
1253#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_COMPACTION)
1254#include <linux/debugfs.h>
1255
Mel Gormand7a57522010-05-24 14:32:25 -07001256
1257/*
1258 * Return an index indicating how much of the available free memory is
1259 * unusable for an allocation of the requested size.
1260 */
1261static int unusable_free_index(unsigned int order,
1262 struct contig_page_info *info)
1263{
1264 /* No free memory is interpreted as all free memory is unusable */
1265 if (info->free_pages == 0)
1266 return 1000;
1267
1268 /*
1269 * Index should be a value between 0 and 1. Return a value to 3
1270 * decimal places.
1271 *
1272 * 0 => no fragmentation
1273 * 1 => high fragmentation
1274 */
1275 return div_u64((info->free_pages - (info->free_blocks_suitable << order)) * 1000ULL, info->free_pages);
1276
1277}
1278
1279static void unusable_show_print(struct seq_file *m,
1280 pg_data_t *pgdat, struct zone *zone)
1281{
1282 unsigned int order;
1283 int index;
1284 struct contig_page_info info;
1285
1286 seq_printf(m, "Node %d, zone %8s ",
1287 pgdat->node_id,
1288 zone->name);
1289 for (order = 0; order < MAX_ORDER; ++order) {
1290 fill_contig_page_info(zone, order, &info);
1291 index = unusable_free_index(order, &info);
1292 seq_printf(m, "%d.%03d ", index / 1000, index % 1000);
1293 }
1294
1295 seq_putc(m, '\n');
1296}
1297
1298/*
1299 * Display unusable free space index
1300 *
1301 * The unusable free space index measures how much of the available free
1302 * memory cannot be used to satisfy an allocation of a given size and is a
1303 * value between 0 and 1. The higher the value, the more of free memory is
1304 * unusable and by implication, the worse the external fragmentation is. This
1305 * can be expressed as a percentage by multiplying by 100.
1306 */
1307static int unusable_show(struct seq_file *m, void *arg)
1308{
1309 pg_data_t *pgdat = (pg_data_t *)arg;
1310
1311 /* check memoryless node */
Lai Jiangshana47b53c2012-12-12 13:51:37 -08001312 if (!node_state(pgdat->node_id, N_MEMORY))
Mel Gormand7a57522010-05-24 14:32:25 -07001313 return 0;
1314
1315 walk_zones_in_node(m, pgdat, unusable_show_print);
1316
1317 return 0;
1318}
1319
1320static const struct seq_operations unusable_op = {
1321 .start = frag_start,
1322 .next = frag_next,
1323 .stop = frag_stop,
1324 .show = unusable_show,
1325};
1326
1327static int unusable_open(struct inode *inode, struct file *file)
1328{
1329 return seq_open(file, &unusable_op);
1330}
1331
1332static const struct file_operations unusable_file_ops = {
1333 .open = unusable_open,
1334 .read = seq_read,
1335 .llseek = seq_lseek,
1336 .release = seq_release,
1337};
1338
Mel Gormanf1a5ab12010-05-24 14:32:26 -07001339static void extfrag_show_print(struct seq_file *m,
1340 pg_data_t *pgdat, struct zone *zone)
1341{
1342 unsigned int order;
1343 int index;
1344
1345 /* Alloc on stack as interrupts are disabled for zone walk */
1346 struct contig_page_info info;
1347
1348 seq_printf(m, "Node %d, zone %8s ",
1349 pgdat->node_id,
1350 zone->name);
1351 for (order = 0; order < MAX_ORDER; ++order) {
1352 fill_contig_page_info(zone, order, &info);
Mel Gorman56de7262010-05-24 14:32:30 -07001353 index = __fragmentation_index(order, &info);
Mel Gormanf1a5ab12010-05-24 14:32:26 -07001354 seq_printf(m, "%d.%03d ", index / 1000, index % 1000);
1355 }
1356
1357 seq_putc(m, '\n');
1358}
1359
1360/*
1361 * Display fragmentation index for orders that allocations would fail for
1362 */
1363static int extfrag_show(struct seq_file *m, void *arg)
1364{
1365 pg_data_t *pgdat = (pg_data_t *)arg;
1366
1367 walk_zones_in_node(m, pgdat, extfrag_show_print);
1368
1369 return 0;
1370}
1371
1372static const struct seq_operations extfrag_op = {
1373 .start = frag_start,
1374 .next = frag_next,
1375 .stop = frag_stop,
1376 .show = extfrag_show,
1377};
1378
1379static int extfrag_open(struct inode *inode, struct file *file)
1380{
1381 return seq_open(file, &extfrag_op);
1382}
1383
1384static const struct file_operations extfrag_file_ops = {
1385 .open = extfrag_open,
1386 .read = seq_read,
1387 .llseek = seq_lseek,
1388 .release = seq_release,
1389};
1390
Mel Gormand7a57522010-05-24 14:32:25 -07001391static int __init extfrag_debug_init(void)
1392{
Sasikantha babubde8bd82012-05-29 15:06:22 -07001393 struct dentry *extfrag_debug_root;
1394
Mel Gormand7a57522010-05-24 14:32:25 -07001395 extfrag_debug_root = debugfs_create_dir("extfrag", NULL);
1396 if (!extfrag_debug_root)
1397 return -ENOMEM;
1398
1399 if (!debugfs_create_file("unusable_index", 0444,
1400 extfrag_debug_root, NULL, &unusable_file_ops))
Sasikantha babubde8bd82012-05-29 15:06:22 -07001401 goto fail;
Mel Gormand7a57522010-05-24 14:32:25 -07001402
Mel Gormanf1a5ab12010-05-24 14:32:26 -07001403 if (!debugfs_create_file("extfrag_index", 0444,
1404 extfrag_debug_root, NULL, &extfrag_file_ops))
Sasikantha babubde8bd82012-05-29 15:06:22 -07001405 goto fail;
Mel Gormanf1a5ab12010-05-24 14:32:26 -07001406
Mel Gormand7a57522010-05-24 14:32:25 -07001407 return 0;
Sasikantha babubde8bd82012-05-29 15:06:22 -07001408fail:
1409 debugfs_remove_recursive(extfrag_debug_root);
1410 return -ENOMEM;
Mel Gormand7a57522010-05-24 14:32:25 -07001411}
1412
1413module_init(extfrag_debug_init);
1414#endif