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[people/arne_f/kernel.git] / mm / vmstat.c
1 /*
2 * linux/mm/vmstat.c
3 *
4 * Manages VM statistics
5 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
6 *
7 * zoned VM statistics
8 * Copyright (C) 2006 Silicon Graphics, Inc.,
9 * Christoph Lameter <christoph@lameter.com>
10 * Copyright (C) 2008-2014 Christoph Lameter
11 */
12 #include <linux/fs.h>
13 #include <linux/mm.h>
14 #include <linux/err.h>
15 #include <linux/module.h>
16 #include <linux/slab.h>
17 #include <linux/cpu.h>
18 #include <linux/cpumask.h>
19 #include <linux/vmstat.h>
20 #include <linux/proc_fs.h>
21 #include <linux/seq_file.h>
22 #include <linux/debugfs.h>
23 #include <linux/sched.h>
24 #include <linux/math64.h>
25 #include <linux/writeback.h>
26 #include <linux/compaction.h>
27 #include <linux/mm_inline.h>
28 #include <linux/page_ext.h>
29 #include <linux/page_owner.h>
30
31 #include "internal.h"
32
33 #define NUMA_STATS_THRESHOLD (U16_MAX - 2)
34
35 #ifdef CONFIG_VM_EVENT_COUNTERS
36 DEFINE_PER_CPU(struct vm_event_state, vm_event_states) = {{0}};
37 EXPORT_PER_CPU_SYMBOL(vm_event_states);
38
39 static void sum_vm_events(unsigned long *ret)
40 {
41 int cpu;
42 int i;
43
44 memset(ret, 0, NR_VM_EVENT_ITEMS * sizeof(unsigned long));
45
46 for_each_online_cpu(cpu) {
47 struct vm_event_state *this = &per_cpu(vm_event_states, cpu);
48
49 for (i = 0; i < NR_VM_EVENT_ITEMS; i++)
50 ret[i] += this->event[i];
51 }
52 }
53
54 /*
55 * Accumulate the vm event counters across all CPUs.
56 * The result is unavoidably approximate - it can change
57 * during and after execution of this function.
58 */
59 void all_vm_events(unsigned long *ret)
60 {
61 get_online_cpus();
62 sum_vm_events(ret);
63 put_online_cpus();
64 }
65 EXPORT_SYMBOL_GPL(all_vm_events);
66
67 /*
68 * Fold the foreign cpu events into our own.
69 *
70 * This is adding to the events on one processor
71 * but keeps the global counts constant.
72 */
73 void vm_events_fold_cpu(int cpu)
74 {
75 struct vm_event_state *fold_state = &per_cpu(vm_event_states, cpu);
76 int i;
77
78 for (i = 0; i < NR_VM_EVENT_ITEMS; i++) {
79 count_vm_events(i, fold_state->event[i]);
80 fold_state->event[i] = 0;
81 }
82 }
83
84 #endif /* CONFIG_VM_EVENT_COUNTERS */
85
86 /*
87 * Manage combined zone based / global counters
88 *
89 * vm_stat contains the global counters
90 */
91 atomic_long_t vm_zone_stat[NR_VM_ZONE_STAT_ITEMS] __cacheline_aligned_in_smp;
92 atomic_long_t vm_numa_stat[NR_VM_NUMA_STAT_ITEMS] __cacheline_aligned_in_smp;
93 atomic_long_t vm_node_stat[NR_VM_NODE_STAT_ITEMS] __cacheline_aligned_in_smp;
94 EXPORT_SYMBOL(vm_zone_stat);
95 EXPORT_SYMBOL(vm_numa_stat);
96 EXPORT_SYMBOL(vm_node_stat);
97
98 #ifdef CONFIG_SMP
99
100 int calculate_pressure_threshold(struct zone *zone)
101 {
102 int threshold;
103 int watermark_distance;
104
105 /*
106 * As vmstats are not up to date, there is drift between the estimated
107 * and real values. For high thresholds and a high number of CPUs, it
108 * is possible for the min watermark to be breached while the estimated
109 * value looks fine. The pressure threshold is a reduced value such
110 * that even the maximum amount of drift will not accidentally breach
111 * the min watermark
112 */
113 watermark_distance = low_wmark_pages(zone) - min_wmark_pages(zone);
114 threshold = max(1, (int)(watermark_distance / num_online_cpus()));
115
116 /*
117 * Maximum threshold is 125
118 */
119 threshold = min(125, threshold);
120
121 return threshold;
122 }
123
124 int calculate_normal_threshold(struct zone *zone)
125 {
126 int threshold;
127 int mem; /* memory in 128 MB units */
128
129 /*
130 * The threshold scales with the number of processors and the amount
131 * of memory per zone. More memory means that we can defer updates for
132 * longer, more processors could lead to more contention.
133 * fls() is used to have a cheap way of logarithmic scaling.
134 *
135 * Some sample thresholds:
136 *
137 * Threshold Processors (fls) Zonesize fls(mem+1)
138 * ------------------------------------------------------------------
139 * 8 1 1 0.9-1 GB 4
140 * 16 2 2 0.9-1 GB 4
141 * 20 2 2 1-2 GB 5
142 * 24 2 2 2-4 GB 6
143 * 28 2 2 4-8 GB 7
144 * 32 2 2 8-16 GB 8
145 * 4 2 2 <128M 1
146 * 30 4 3 2-4 GB 5
147 * 48 4 3 8-16 GB 8
148 * 32 8 4 1-2 GB 4
149 * 32 8 4 0.9-1GB 4
150 * 10 16 5 <128M 1
151 * 40 16 5 900M 4
152 * 70 64 7 2-4 GB 5
153 * 84 64 7 4-8 GB 6
154 * 108 512 9 4-8 GB 6
155 * 125 1024 10 8-16 GB 8
156 * 125 1024 10 16-32 GB 9
157 */
158
159 mem = zone->managed_pages >> (27 - PAGE_SHIFT);
160
161 threshold = 2 * fls(num_online_cpus()) * (1 + fls(mem));
162
163 /*
164 * Maximum threshold is 125
165 */
166 threshold = min(125, threshold);
167
168 return threshold;
169 }
170
171 /*
172 * Refresh the thresholds for each zone.
173 */
174 void refresh_zone_stat_thresholds(void)
175 {
176 struct pglist_data *pgdat;
177 struct zone *zone;
178 int cpu;
179 int threshold;
180
181 /* Zero current pgdat thresholds */
182 for_each_online_pgdat(pgdat) {
183 for_each_online_cpu(cpu) {
184 per_cpu_ptr(pgdat->per_cpu_nodestats, cpu)->stat_threshold = 0;
185 }
186 }
187
188 for_each_populated_zone(zone) {
189 struct pglist_data *pgdat = zone->zone_pgdat;
190 unsigned long max_drift, tolerate_drift;
191
192 threshold = calculate_normal_threshold(zone);
193
194 for_each_online_cpu(cpu) {
195 int pgdat_threshold;
196
197 per_cpu_ptr(zone->pageset, cpu)->stat_threshold
198 = threshold;
199
200 /* Base nodestat threshold on the largest populated zone. */
201 pgdat_threshold = per_cpu_ptr(pgdat->per_cpu_nodestats, cpu)->stat_threshold;
202 per_cpu_ptr(pgdat->per_cpu_nodestats, cpu)->stat_threshold
203 = max(threshold, pgdat_threshold);
204 }
205
206 /*
207 * Only set percpu_drift_mark if there is a danger that
208 * NR_FREE_PAGES reports the low watermark is ok when in fact
209 * the min watermark could be breached by an allocation
210 */
211 tolerate_drift = low_wmark_pages(zone) - min_wmark_pages(zone);
212 max_drift = num_online_cpus() * threshold;
213 if (max_drift > tolerate_drift)
214 zone->percpu_drift_mark = high_wmark_pages(zone) +
215 max_drift;
216 }
217 }
218
219 void set_pgdat_percpu_threshold(pg_data_t *pgdat,
220 int (*calculate_pressure)(struct zone *))
221 {
222 struct zone *zone;
223 int cpu;
224 int threshold;
225 int i;
226
227 for (i = 0; i < pgdat->nr_zones; i++) {
228 zone = &pgdat->node_zones[i];
229 if (!zone->percpu_drift_mark)
230 continue;
231
232 threshold = (*calculate_pressure)(zone);
233 for_each_online_cpu(cpu)
234 per_cpu_ptr(zone->pageset, cpu)->stat_threshold
235 = threshold;
236 }
237 }
238
239 /*
240 * For use when we know that interrupts are disabled,
241 * or when we know that preemption is disabled and that
242 * particular counter cannot be updated from interrupt context.
243 */
244 void __mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
245 long delta)
246 {
247 struct per_cpu_pageset __percpu *pcp = zone->pageset;
248 s8 __percpu *p = pcp->vm_stat_diff + item;
249 long x;
250 long t;
251
252 x = delta + __this_cpu_read(*p);
253
254 t = __this_cpu_read(pcp->stat_threshold);
255
256 if (unlikely(x > t || x < -t)) {
257 zone_page_state_add(x, zone, item);
258 x = 0;
259 }
260 __this_cpu_write(*p, x);
261 }
262 EXPORT_SYMBOL(__mod_zone_page_state);
263
264 void __mod_node_page_state(struct pglist_data *pgdat, enum node_stat_item item,
265 long delta)
266 {
267 struct per_cpu_nodestat __percpu *pcp = pgdat->per_cpu_nodestats;
268 s8 __percpu *p = pcp->vm_node_stat_diff + item;
269 long x;
270 long t;
271
272 x = delta + __this_cpu_read(*p);
273
274 t = __this_cpu_read(pcp->stat_threshold);
275
276 if (unlikely(x > t || x < -t)) {
277 node_page_state_add(x, pgdat, item);
278 x = 0;
279 }
280 __this_cpu_write(*p, x);
281 }
282 EXPORT_SYMBOL(__mod_node_page_state);
283
284 /*
285 * Optimized increment and decrement functions.
286 *
287 * These are only for a single page and therefore can take a struct page *
288 * argument instead of struct zone *. This allows the inclusion of the code
289 * generated for page_zone(page) into the optimized functions.
290 *
291 * No overflow check is necessary and therefore the differential can be
292 * incremented or decremented in place which may allow the compilers to
293 * generate better code.
294 * The increment or decrement is known and therefore one boundary check can
295 * be omitted.
296 *
297 * NOTE: These functions are very performance sensitive. Change only
298 * with care.
299 *
300 * Some processors have inc/dec instructions that are atomic vs an interrupt.
301 * However, the code must first determine the differential location in a zone
302 * based on the processor number and then inc/dec the counter. There is no
303 * guarantee without disabling preemption that the processor will not change
304 * in between and therefore the atomicity vs. interrupt cannot be exploited
305 * in a useful way here.
306 */
307 void __inc_zone_state(struct zone *zone, enum zone_stat_item item)
308 {
309 struct per_cpu_pageset __percpu *pcp = zone->pageset;
310 s8 __percpu *p = pcp->vm_stat_diff + item;
311 s8 v, t;
312
313 v = __this_cpu_inc_return(*p);
314 t = __this_cpu_read(pcp->stat_threshold);
315 if (unlikely(v > t)) {
316 s8 overstep = t >> 1;
317
318 zone_page_state_add(v + overstep, zone, item);
319 __this_cpu_write(*p, -overstep);
320 }
321 }
322
323 void __inc_node_state(struct pglist_data *pgdat, enum node_stat_item item)
324 {
325 struct per_cpu_nodestat __percpu *pcp = pgdat->per_cpu_nodestats;
326 s8 __percpu *p = pcp->vm_node_stat_diff + item;
327 s8 v, t;
328
329 v = __this_cpu_inc_return(*p);
330 t = __this_cpu_read(pcp->stat_threshold);
331 if (unlikely(v > t)) {
332 s8 overstep = t >> 1;
333
334 node_page_state_add(v + overstep, pgdat, item);
335 __this_cpu_write(*p, -overstep);
336 }
337 }
338
339 void __inc_zone_page_state(struct page *page, enum zone_stat_item item)
340 {
341 __inc_zone_state(page_zone(page), item);
342 }
343 EXPORT_SYMBOL(__inc_zone_page_state);
344
345 void __inc_node_page_state(struct page *page, enum node_stat_item item)
346 {
347 __inc_node_state(page_pgdat(page), item);
348 }
349 EXPORT_SYMBOL(__inc_node_page_state);
350
351 void __dec_zone_state(struct zone *zone, enum zone_stat_item item)
352 {
353 struct per_cpu_pageset __percpu *pcp = zone->pageset;
354 s8 __percpu *p = pcp->vm_stat_diff + item;
355 s8 v, t;
356
357 v = __this_cpu_dec_return(*p);
358 t = __this_cpu_read(pcp->stat_threshold);
359 if (unlikely(v < - t)) {
360 s8 overstep = t >> 1;
361
362 zone_page_state_add(v - overstep, zone, item);
363 __this_cpu_write(*p, overstep);
364 }
365 }
366
367 void __dec_node_state(struct pglist_data *pgdat, enum node_stat_item item)
368 {
369 struct per_cpu_nodestat __percpu *pcp = pgdat->per_cpu_nodestats;
370 s8 __percpu *p = pcp->vm_node_stat_diff + item;
371 s8 v, t;
372
373 v = __this_cpu_dec_return(*p);
374 t = __this_cpu_read(pcp->stat_threshold);
375 if (unlikely(v < - t)) {
376 s8 overstep = t >> 1;
377
378 node_page_state_add(v - overstep, pgdat, item);
379 __this_cpu_write(*p, overstep);
380 }
381 }
382
383 void __dec_zone_page_state(struct page *page, enum zone_stat_item item)
384 {
385 __dec_zone_state(page_zone(page), item);
386 }
387 EXPORT_SYMBOL(__dec_zone_page_state);
388
389 void __dec_node_page_state(struct page *page, enum node_stat_item item)
390 {
391 __dec_node_state(page_pgdat(page), item);
392 }
393 EXPORT_SYMBOL(__dec_node_page_state);
394
395 #ifdef CONFIG_HAVE_CMPXCHG_LOCAL
396 /*
397 * If we have cmpxchg_local support then we do not need to incur the overhead
398 * that comes with local_irq_save/restore if we use this_cpu_cmpxchg.
399 *
400 * mod_state() modifies the zone counter state through atomic per cpu
401 * operations.
402 *
403 * Overstep mode specifies how overstep should handled:
404 * 0 No overstepping
405 * 1 Overstepping half of threshold
406 * -1 Overstepping minus half of threshold
407 */
408 static inline void mod_zone_state(struct zone *zone,
409 enum zone_stat_item item, long delta, int overstep_mode)
410 {
411 struct per_cpu_pageset __percpu *pcp = zone->pageset;
412 s8 __percpu *p = pcp->vm_stat_diff + item;
413 long o, n, t, z;
414
415 do {
416 z = 0; /* overflow to zone counters */
417
418 /*
419 * The fetching of the stat_threshold is racy. We may apply
420 * a counter threshold to the wrong the cpu if we get
421 * rescheduled while executing here. However, the next
422 * counter update will apply the threshold again and
423 * therefore bring the counter under the threshold again.
424 *
425 * Most of the time the thresholds are the same anyways
426 * for all cpus in a zone.
427 */
428 t = this_cpu_read(pcp->stat_threshold);
429
430 o = this_cpu_read(*p);
431 n = delta + o;
432
433 if (n > t || n < -t) {
434 int os = overstep_mode * (t >> 1) ;
435
436 /* Overflow must be added to zone counters */
437 z = n + os;
438 n = -os;
439 }
440 } while (this_cpu_cmpxchg(*p, o, n) != o);
441
442 if (z)
443 zone_page_state_add(z, zone, item);
444 }
445
446 void mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
447 long delta)
448 {
449 mod_zone_state(zone, item, delta, 0);
450 }
451 EXPORT_SYMBOL(mod_zone_page_state);
452
453 void inc_zone_page_state(struct page *page, enum zone_stat_item item)
454 {
455 mod_zone_state(page_zone(page), item, 1, 1);
456 }
457 EXPORT_SYMBOL(inc_zone_page_state);
458
459 void dec_zone_page_state(struct page *page, enum zone_stat_item item)
460 {
461 mod_zone_state(page_zone(page), item, -1, -1);
462 }
463 EXPORT_SYMBOL(dec_zone_page_state);
464
465 static inline void mod_node_state(struct pglist_data *pgdat,
466 enum node_stat_item item, int delta, int overstep_mode)
467 {
468 struct per_cpu_nodestat __percpu *pcp = pgdat->per_cpu_nodestats;
469 s8 __percpu *p = pcp->vm_node_stat_diff + item;
470 long o, n, t, z;
471
472 do {
473 z = 0; /* overflow to node counters */
474
475 /*
476 * The fetching of the stat_threshold is racy. We may apply
477 * a counter threshold to the wrong the cpu if we get
478 * rescheduled while executing here. However, the next
479 * counter update will apply the threshold again and
480 * therefore bring the counter under the threshold again.
481 *
482 * Most of the time the thresholds are the same anyways
483 * for all cpus in a node.
484 */
485 t = this_cpu_read(pcp->stat_threshold);
486
487 o = this_cpu_read(*p);
488 n = delta + o;
489
490 if (n > t || n < -t) {
491 int os = overstep_mode * (t >> 1) ;
492
493 /* Overflow must be added to node counters */
494 z = n + os;
495 n = -os;
496 }
497 } while (this_cpu_cmpxchg(*p, o, n) != o);
498
499 if (z)
500 node_page_state_add(z, pgdat, item);
501 }
502
503 void mod_node_page_state(struct pglist_data *pgdat, enum node_stat_item item,
504 long delta)
505 {
506 mod_node_state(pgdat, item, delta, 0);
507 }
508 EXPORT_SYMBOL(mod_node_page_state);
509
510 void inc_node_state(struct pglist_data *pgdat, enum node_stat_item item)
511 {
512 mod_node_state(pgdat, item, 1, 1);
513 }
514
515 void inc_node_page_state(struct page *page, enum node_stat_item item)
516 {
517 mod_node_state(page_pgdat(page), item, 1, 1);
518 }
519 EXPORT_SYMBOL(inc_node_page_state);
520
521 void dec_node_page_state(struct page *page, enum node_stat_item item)
522 {
523 mod_node_state(page_pgdat(page), item, -1, -1);
524 }
525 EXPORT_SYMBOL(dec_node_page_state);
526 #else
527 /*
528 * Use interrupt disable to serialize counter updates
529 */
530 void mod_zone_page_state(struct zone *zone, enum zone_stat_item item,
531 long delta)
532 {
533 unsigned long flags;
534
535 local_irq_save(flags);
536 __mod_zone_page_state(zone, item, delta);
537 local_irq_restore(flags);
538 }
539 EXPORT_SYMBOL(mod_zone_page_state);
540
541 void inc_zone_page_state(struct page *page, enum zone_stat_item item)
542 {
543 unsigned long flags;
544 struct zone *zone;
545
546 zone = page_zone(page);
547 local_irq_save(flags);
548 __inc_zone_state(zone, item);
549 local_irq_restore(flags);
550 }
551 EXPORT_SYMBOL(inc_zone_page_state);
552
553 void dec_zone_page_state(struct page *page, enum zone_stat_item item)
554 {
555 unsigned long flags;
556
557 local_irq_save(flags);
558 __dec_zone_page_state(page, item);
559 local_irq_restore(flags);
560 }
561 EXPORT_SYMBOL(dec_zone_page_state);
562
563 void inc_node_state(struct pglist_data *pgdat, enum node_stat_item item)
564 {
565 unsigned long flags;
566
567 local_irq_save(flags);
568 __inc_node_state(pgdat, item);
569 local_irq_restore(flags);
570 }
571 EXPORT_SYMBOL(inc_node_state);
572
573 void mod_node_page_state(struct pglist_data *pgdat, enum node_stat_item item,
574 long delta)
575 {
576 unsigned long flags;
577
578 local_irq_save(flags);
579 __mod_node_page_state(pgdat, item, delta);
580 local_irq_restore(flags);
581 }
582 EXPORT_SYMBOL(mod_node_page_state);
583
584 void inc_node_page_state(struct page *page, enum node_stat_item item)
585 {
586 unsigned long flags;
587 struct pglist_data *pgdat;
588
589 pgdat = page_pgdat(page);
590 local_irq_save(flags);
591 __inc_node_state(pgdat, item);
592 local_irq_restore(flags);
593 }
594 EXPORT_SYMBOL(inc_node_page_state);
595
596 void dec_node_page_state(struct page *page, enum node_stat_item item)
597 {
598 unsigned long flags;
599
600 local_irq_save(flags);
601 __dec_node_page_state(page, item);
602 local_irq_restore(flags);
603 }
604 EXPORT_SYMBOL(dec_node_page_state);
605 #endif
606
607 /*
608 * Fold a differential into the global counters.
609 * Returns the number of counters updated.
610 */
611 #ifdef CONFIG_NUMA
612 static int fold_diff(int *zone_diff, int *numa_diff, int *node_diff)
613 {
614 int i;
615 int changes = 0;
616
617 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
618 if (zone_diff[i]) {
619 atomic_long_add(zone_diff[i], &vm_zone_stat[i]);
620 changes++;
621 }
622
623 for (i = 0; i < NR_VM_NUMA_STAT_ITEMS; i++)
624 if (numa_diff[i]) {
625 atomic_long_add(numa_diff[i], &vm_numa_stat[i]);
626 changes++;
627 }
628
629 for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++)
630 if (node_diff[i]) {
631 atomic_long_add(node_diff[i], &vm_node_stat[i]);
632 changes++;
633 }
634 return changes;
635 }
636 #else
637 static int fold_diff(int *zone_diff, int *node_diff)
638 {
639 int i;
640 int changes = 0;
641
642 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
643 if (zone_diff[i]) {
644 atomic_long_add(zone_diff[i], &vm_zone_stat[i]);
645 changes++;
646 }
647
648 for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++)
649 if (node_diff[i]) {
650 atomic_long_add(node_diff[i], &vm_node_stat[i]);
651 changes++;
652 }
653 return changes;
654 }
655 #endif /* CONFIG_NUMA */
656
657 /*
658 * Update the zone counters for the current cpu.
659 *
660 * Note that refresh_cpu_vm_stats strives to only access
661 * node local memory. The per cpu pagesets on remote zones are placed
662 * in the memory local to the processor using that pageset. So the
663 * loop over all zones will access a series of cachelines local to
664 * the processor.
665 *
666 * The call to zone_page_state_add updates the cachelines with the
667 * statistics in the remote zone struct as well as the global cachelines
668 * with the global counters. These could cause remote node cache line
669 * bouncing and will have to be only done when necessary.
670 *
671 * The function returns the number of global counters updated.
672 */
673 static int refresh_cpu_vm_stats(bool do_pagesets)
674 {
675 struct pglist_data *pgdat;
676 struct zone *zone;
677 int i;
678 int global_zone_diff[NR_VM_ZONE_STAT_ITEMS] = { 0, };
679 #ifdef CONFIG_NUMA
680 int global_numa_diff[NR_VM_NUMA_STAT_ITEMS] = { 0, };
681 #endif
682 int global_node_diff[NR_VM_NODE_STAT_ITEMS] = { 0, };
683 int changes = 0;
684
685 for_each_populated_zone(zone) {
686 struct per_cpu_pageset __percpu *p = zone->pageset;
687
688 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) {
689 int v;
690
691 v = this_cpu_xchg(p->vm_stat_diff[i], 0);
692 if (v) {
693
694 atomic_long_add(v, &zone->vm_stat[i]);
695 global_zone_diff[i] += v;
696 #ifdef CONFIG_NUMA
697 /* 3 seconds idle till flush */
698 __this_cpu_write(p->expire, 3);
699 #endif
700 }
701 }
702 #ifdef CONFIG_NUMA
703 for (i = 0; i < NR_VM_NUMA_STAT_ITEMS; i++) {
704 int v;
705
706 v = this_cpu_xchg(p->vm_numa_stat_diff[i], 0);
707 if (v) {
708
709 atomic_long_add(v, &zone->vm_numa_stat[i]);
710 global_numa_diff[i] += v;
711 __this_cpu_write(p->expire, 3);
712 }
713 }
714
715 if (do_pagesets) {
716 cond_resched();
717 /*
718 * Deal with draining the remote pageset of this
719 * processor
720 *
721 * Check if there are pages remaining in this pageset
722 * if not then there is nothing to expire.
723 */
724 if (!__this_cpu_read(p->expire) ||
725 !__this_cpu_read(p->pcp.count))
726 continue;
727
728 /*
729 * We never drain zones local to this processor.
730 */
731 if (zone_to_nid(zone) == numa_node_id()) {
732 __this_cpu_write(p->expire, 0);
733 continue;
734 }
735
736 if (__this_cpu_dec_return(p->expire))
737 continue;
738
739 if (__this_cpu_read(p->pcp.count)) {
740 drain_zone_pages(zone, this_cpu_ptr(&p->pcp));
741 changes++;
742 }
743 }
744 #endif
745 }
746
747 for_each_online_pgdat(pgdat) {
748 struct per_cpu_nodestat __percpu *p = pgdat->per_cpu_nodestats;
749
750 for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) {
751 int v;
752
753 v = this_cpu_xchg(p->vm_node_stat_diff[i], 0);
754 if (v) {
755 atomic_long_add(v, &pgdat->vm_stat[i]);
756 global_node_diff[i] += v;
757 }
758 }
759 }
760
761 #ifdef CONFIG_NUMA
762 changes += fold_diff(global_zone_diff, global_numa_diff,
763 global_node_diff);
764 #else
765 changes += fold_diff(global_zone_diff, global_node_diff);
766 #endif
767 return changes;
768 }
769
770 /*
771 * Fold the data for an offline cpu into the global array.
772 * There cannot be any access by the offline cpu and therefore
773 * synchronization is simplified.
774 */
775 void cpu_vm_stats_fold(int cpu)
776 {
777 struct pglist_data *pgdat;
778 struct zone *zone;
779 int i;
780 int global_zone_diff[NR_VM_ZONE_STAT_ITEMS] = { 0, };
781 #ifdef CONFIG_NUMA
782 int global_numa_diff[NR_VM_NUMA_STAT_ITEMS] = { 0, };
783 #endif
784 int global_node_diff[NR_VM_NODE_STAT_ITEMS] = { 0, };
785
786 for_each_populated_zone(zone) {
787 struct per_cpu_pageset *p;
788
789 p = per_cpu_ptr(zone->pageset, cpu);
790
791 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
792 if (p->vm_stat_diff[i]) {
793 int v;
794
795 v = p->vm_stat_diff[i];
796 p->vm_stat_diff[i] = 0;
797 atomic_long_add(v, &zone->vm_stat[i]);
798 global_zone_diff[i] += v;
799 }
800
801 #ifdef CONFIG_NUMA
802 for (i = 0; i < NR_VM_NUMA_STAT_ITEMS; i++)
803 if (p->vm_numa_stat_diff[i]) {
804 int v;
805
806 v = p->vm_numa_stat_diff[i];
807 p->vm_numa_stat_diff[i] = 0;
808 atomic_long_add(v, &zone->vm_numa_stat[i]);
809 global_numa_diff[i] += v;
810 }
811 #endif
812 }
813
814 for_each_online_pgdat(pgdat) {
815 struct per_cpu_nodestat *p;
816
817 p = per_cpu_ptr(pgdat->per_cpu_nodestats, cpu);
818
819 for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++)
820 if (p->vm_node_stat_diff[i]) {
821 int v;
822
823 v = p->vm_node_stat_diff[i];
824 p->vm_node_stat_diff[i] = 0;
825 atomic_long_add(v, &pgdat->vm_stat[i]);
826 global_node_diff[i] += v;
827 }
828 }
829
830 #ifdef CONFIG_NUMA
831 fold_diff(global_zone_diff, global_numa_diff, global_node_diff);
832 #else
833 fold_diff(global_zone_diff, global_node_diff);
834 #endif
835 }
836
837 /*
838 * this is only called if !populated_zone(zone), which implies no other users of
839 * pset->vm_stat_diff[] exsist.
840 */
841 void drain_zonestat(struct zone *zone, struct per_cpu_pageset *pset)
842 {
843 int i;
844
845 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
846 if (pset->vm_stat_diff[i]) {
847 int v = pset->vm_stat_diff[i];
848 pset->vm_stat_diff[i] = 0;
849 atomic_long_add(v, &zone->vm_stat[i]);
850 atomic_long_add(v, &vm_zone_stat[i]);
851 }
852
853 #ifdef CONFIG_NUMA
854 for (i = 0; i < NR_VM_NUMA_STAT_ITEMS; i++)
855 if (pset->vm_numa_stat_diff[i]) {
856 int v = pset->vm_numa_stat_diff[i];
857
858 pset->vm_numa_stat_diff[i] = 0;
859 atomic_long_add(v, &zone->vm_numa_stat[i]);
860 atomic_long_add(v, &vm_numa_stat[i]);
861 }
862 #endif
863 }
864 #endif
865
866 #ifdef CONFIG_NUMA
867 void __inc_numa_state(struct zone *zone,
868 enum numa_stat_item item)
869 {
870 struct per_cpu_pageset __percpu *pcp = zone->pageset;
871 u16 __percpu *p = pcp->vm_numa_stat_diff + item;
872 u16 v;
873
874 v = __this_cpu_inc_return(*p);
875
876 if (unlikely(v > NUMA_STATS_THRESHOLD)) {
877 zone_numa_state_add(v, zone, item);
878 __this_cpu_write(*p, 0);
879 }
880 }
881
882 /*
883 * Determine the per node value of a stat item. This function
884 * is called frequently in a NUMA machine, so try to be as
885 * frugal as possible.
886 */
887 unsigned long sum_zone_node_page_state(int node,
888 enum zone_stat_item item)
889 {
890 struct zone *zones = NODE_DATA(node)->node_zones;
891 int i;
892 unsigned long count = 0;
893
894 for (i = 0; i < MAX_NR_ZONES; i++)
895 count += zone_page_state(zones + i, item);
896
897 return count;
898 }
899
900 /*
901 * Determine the per node value of a numa stat item. To avoid deviation,
902 * the per cpu stat number in vm_numa_stat_diff[] is also included.
903 */
904 unsigned long sum_zone_numa_state(int node,
905 enum numa_stat_item item)
906 {
907 struct zone *zones = NODE_DATA(node)->node_zones;
908 int i;
909 unsigned long count = 0;
910
911 for (i = 0; i < MAX_NR_ZONES; i++)
912 count += zone_numa_state_snapshot(zones + i, item);
913
914 return count;
915 }
916
917 /*
918 * Determine the per node value of a stat item.
919 */
920 unsigned long node_page_state(struct pglist_data *pgdat,
921 enum node_stat_item item)
922 {
923 long x = atomic_long_read(&pgdat->vm_stat[item]);
924 #ifdef CONFIG_SMP
925 if (x < 0)
926 x = 0;
927 #endif
928 return x;
929 }
930 #endif
931
932 #ifdef CONFIG_COMPACTION
933
934 struct contig_page_info {
935 unsigned long free_pages;
936 unsigned long free_blocks_total;
937 unsigned long free_blocks_suitable;
938 };
939
940 /*
941 * Calculate the number of free pages in a zone, how many contiguous
942 * pages are free and how many are large enough to satisfy an allocation of
943 * the target size. Note that this function makes no attempt to estimate
944 * how many suitable free blocks there *might* be if MOVABLE pages were
945 * migrated. Calculating that is possible, but expensive and can be
946 * figured out from userspace
947 */
948 static void fill_contig_page_info(struct zone *zone,
949 unsigned int suitable_order,
950 struct contig_page_info *info)
951 {
952 unsigned int order;
953
954 info->free_pages = 0;
955 info->free_blocks_total = 0;
956 info->free_blocks_suitable = 0;
957
958 for (order = 0; order < MAX_ORDER; order++) {
959 unsigned long blocks;
960
961 /* Count number of free blocks */
962 blocks = zone->free_area[order].nr_free;
963 info->free_blocks_total += blocks;
964
965 /* Count free base pages */
966 info->free_pages += blocks << order;
967
968 /* Count the suitable free blocks */
969 if (order >= suitable_order)
970 info->free_blocks_suitable += blocks <<
971 (order - suitable_order);
972 }
973 }
974
975 /*
976 * A fragmentation index only makes sense if an allocation of a requested
977 * size would fail. If that is true, the fragmentation index indicates
978 * whether external fragmentation or a lack of memory was the problem.
979 * The value can be used to determine if page reclaim or compaction
980 * should be used
981 */
982 static int __fragmentation_index(unsigned int order, struct contig_page_info *info)
983 {
984 unsigned long requested = 1UL << order;
985
986 if (WARN_ON_ONCE(order >= MAX_ORDER))
987 return 0;
988
989 if (!info->free_blocks_total)
990 return 0;
991
992 /* Fragmentation index only makes sense when a request would fail */
993 if (info->free_blocks_suitable)
994 return -1000;
995
996 /*
997 * Index is between 0 and 1 so return within 3 decimal places
998 *
999 * 0 => allocation would fail due to lack of memory
1000 * 1 => allocation would fail due to fragmentation
1001 */
1002 return 1000 - div_u64( (1000+(div_u64(info->free_pages * 1000ULL, requested))), info->free_blocks_total);
1003 }
1004
1005 /* Same as __fragmentation index but allocs contig_page_info on stack */
1006 int fragmentation_index(struct zone *zone, unsigned int order)
1007 {
1008 struct contig_page_info info;
1009
1010 fill_contig_page_info(zone, order, &info);
1011 return __fragmentation_index(order, &info);
1012 }
1013 #endif
1014
1015 #if defined(CONFIG_PROC_FS) || defined(CONFIG_SYSFS) || defined(CONFIG_NUMA)
1016 #ifdef CONFIG_ZONE_DMA
1017 #define TEXT_FOR_DMA(xx) xx "_dma",
1018 #else
1019 #define TEXT_FOR_DMA(xx)
1020 #endif
1021
1022 #ifdef CONFIG_ZONE_DMA32
1023 #define TEXT_FOR_DMA32(xx) xx "_dma32",
1024 #else
1025 #define TEXT_FOR_DMA32(xx)
1026 #endif
1027
1028 #ifdef CONFIG_HIGHMEM
1029 #define TEXT_FOR_HIGHMEM(xx) xx "_high",
1030 #else
1031 #define TEXT_FOR_HIGHMEM(xx)
1032 #endif
1033
1034 #define TEXTS_FOR_ZONES(xx) TEXT_FOR_DMA(xx) TEXT_FOR_DMA32(xx) xx "_normal", \
1035 TEXT_FOR_HIGHMEM(xx) xx "_movable",
1036
1037 const char * const vmstat_text[] = {
1038 /* enum zone_stat_item countes */
1039 "nr_free_pages",
1040 "nr_zone_inactive_anon",
1041 "nr_zone_active_anon",
1042 "nr_zone_inactive_file",
1043 "nr_zone_active_file",
1044 "nr_zone_unevictable",
1045 "nr_zone_write_pending",
1046 "nr_mlock",
1047 "nr_page_table_pages",
1048 "nr_kernel_stack",
1049 "nr_bounce",
1050 #if IS_ENABLED(CONFIG_ZSMALLOC)
1051 "nr_zspages",
1052 #endif
1053 "nr_free_cma",
1054
1055 /* enum numa_stat_item counters */
1056 #ifdef CONFIG_NUMA
1057 "numa_hit",
1058 "numa_miss",
1059 "numa_foreign",
1060 "numa_interleave",
1061 "numa_local",
1062 "numa_other",
1063 #endif
1064
1065 /* Node-based counters */
1066 "nr_inactive_anon",
1067 "nr_active_anon",
1068 "nr_inactive_file",
1069 "nr_active_file",
1070 "nr_unevictable",
1071 "nr_slab_reclaimable",
1072 "nr_slab_unreclaimable",
1073 "nr_isolated_anon",
1074 "nr_isolated_file",
1075 "workingset_refault",
1076 "workingset_activate",
1077 "workingset_nodereclaim",
1078 "nr_anon_pages",
1079 "nr_mapped",
1080 "nr_file_pages",
1081 "nr_dirty",
1082 "nr_writeback",
1083 "nr_writeback_temp",
1084 "nr_shmem",
1085 "nr_shmem_hugepages",
1086 "nr_shmem_pmdmapped",
1087 "nr_anon_transparent_hugepages",
1088 "nr_unstable",
1089 "nr_vmscan_write",
1090 "nr_vmscan_immediate_reclaim",
1091 "nr_dirtied",
1092 "nr_written",
1093
1094 /* enum writeback_stat_item counters */
1095 "nr_dirty_threshold",
1096 "nr_dirty_background_threshold",
1097
1098 #ifdef CONFIG_VM_EVENT_COUNTERS
1099 /* enum vm_event_item counters */
1100 "pgpgin",
1101 "pgpgout",
1102 "pswpin",
1103 "pswpout",
1104
1105 TEXTS_FOR_ZONES("pgalloc")
1106 TEXTS_FOR_ZONES("allocstall")
1107 TEXTS_FOR_ZONES("pgskip")
1108
1109 "pgfree",
1110 "pgactivate",
1111 "pgdeactivate",
1112 "pglazyfree",
1113
1114 "pgfault",
1115 "pgmajfault",
1116 "pglazyfreed",
1117
1118 "pgrefill",
1119 "pgsteal_kswapd",
1120 "pgsteal_direct",
1121 "pgscan_kswapd",
1122 "pgscan_direct",
1123 "pgscan_direct_throttle",
1124
1125 #ifdef CONFIG_NUMA
1126 "zone_reclaim_failed",
1127 #endif
1128 "pginodesteal",
1129 "slabs_scanned",
1130 "kswapd_inodesteal",
1131 "kswapd_low_wmark_hit_quickly",
1132 "kswapd_high_wmark_hit_quickly",
1133 "pageoutrun",
1134
1135 "pgrotated",
1136
1137 "drop_pagecache",
1138 "drop_slab",
1139 "oom_kill",
1140
1141 #ifdef CONFIG_NUMA_BALANCING
1142 "numa_pte_updates",
1143 "numa_huge_pte_updates",
1144 "numa_hint_faults",
1145 "numa_hint_faults_local",
1146 "numa_pages_migrated",
1147 #endif
1148 #ifdef CONFIG_MIGRATION
1149 "pgmigrate_success",
1150 "pgmigrate_fail",
1151 #endif
1152 #ifdef CONFIG_COMPACTION
1153 "compact_migrate_scanned",
1154 "compact_free_scanned",
1155 "compact_isolated",
1156 "compact_stall",
1157 "compact_fail",
1158 "compact_success",
1159 "compact_daemon_wake",
1160 "compact_daemon_migrate_scanned",
1161 "compact_daemon_free_scanned",
1162 #endif
1163
1164 #ifdef CONFIG_HUGETLB_PAGE
1165 "htlb_buddy_alloc_success",
1166 "htlb_buddy_alloc_fail",
1167 #endif
1168 "unevictable_pgs_culled",
1169 "unevictable_pgs_scanned",
1170 "unevictable_pgs_rescued",
1171 "unevictable_pgs_mlocked",
1172 "unevictable_pgs_munlocked",
1173 "unevictable_pgs_cleared",
1174 "unevictable_pgs_stranded",
1175
1176 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
1177 "thp_fault_alloc",
1178 "thp_fault_fallback",
1179 "thp_collapse_alloc",
1180 "thp_collapse_alloc_failed",
1181 "thp_file_alloc",
1182 "thp_file_mapped",
1183 "thp_split_page",
1184 "thp_split_page_failed",
1185 "thp_deferred_split_page",
1186 "thp_split_pmd",
1187 #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD
1188 "thp_split_pud",
1189 #endif
1190 "thp_zero_page_alloc",
1191 "thp_zero_page_alloc_failed",
1192 "thp_swpout",
1193 "thp_swpout_fallback",
1194 #endif
1195 #ifdef CONFIG_MEMORY_BALLOON
1196 "balloon_inflate",
1197 "balloon_deflate",
1198 #ifdef CONFIG_BALLOON_COMPACTION
1199 "balloon_migrate",
1200 #endif
1201 #endif /* CONFIG_MEMORY_BALLOON */
1202 #ifdef CONFIG_DEBUG_TLBFLUSH
1203 #ifdef CONFIG_SMP
1204 "nr_tlb_remote_flush",
1205 "nr_tlb_remote_flush_received",
1206 #endif /* CONFIG_SMP */
1207 "nr_tlb_local_flush_all",
1208 "nr_tlb_local_flush_one",
1209 #endif /* CONFIG_DEBUG_TLBFLUSH */
1210
1211 #ifdef CONFIG_DEBUG_VM_VMACACHE
1212 "vmacache_find_calls",
1213 "vmacache_find_hits",
1214 "vmacache_full_flushes",
1215 #endif
1216 #ifdef CONFIG_SWAP
1217 "swap_ra",
1218 "swap_ra_hit",
1219 #endif
1220 #endif /* CONFIG_VM_EVENTS_COUNTERS */
1221 };
1222 #endif /* CONFIG_PROC_FS || CONFIG_SYSFS || CONFIG_NUMA */
1223
1224 #if (defined(CONFIG_DEBUG_FS) && defined(CONFIG_COMPACTION)) || \
1225 defined(CONFIG_PROC_FS)
1226 static void *frag_start(struct seq_file *m, loff_t *pos)
1227 {
1228 pg_data_t *pgdat;
1229 loff_t node = *pos;
1230
1231 for (pgdat = first_online_pgdat();
1232 pgdat && node;
1233 pgdat = next_online_pgdat(pgdat))
1234 --node;
1235
1236 return pgdat;
1237 }
1238
1239 static void *frag_next(struct seq_file *m, void *arg, loff_t *pos)
1240 {
1241 pg_data_t *pgdat = (pg_data_t *)arg;
1242
1243 (*pos)++;
1244 return next_online_pgdat(pgdat);
1245 }
1246
1247 static void frag_stop(struct seq_file *m, void *arg)
1248 {
1249 }
1250
1251 /*
1252 * Walk zones in a node and print using a callback.
1253 * If @assert_populated is true, only use callback for zones that are populated.
1254 */
1255 static void walk_zones_in_node(struct seq_file *m, pg_data_t *pgdat,
1256 bool assert_populated, bool nolock,
1257 void (*print)(struct seq_file *m, pg_data_t *, struct zone *))
1258 {
1259 struct zone *zone;
1260 struct zone *node_zones = pgdat->node_zones;
1261 unsigned long flags;
1262
1263 for (zone = node_zones; zone - node_zones < MAX_NR_ZONES; ++zone) {
1264 if (assert_populated && !populated_zone(zone))
1265 continue;
1266
1267 if (!nolock)
1268 spin_lock_irqsave(&zone->lock, flags);
1269 print(m, pgdat, zone);
1270 if (!nolock)
1271 spin_unlock_irqrestore(&zone->lock, flags);
1272 }
1273 }
1274 #endif
1275
1276 #ifdef CONFIG_PROC_FS
1277 static void frag_show_print(struct seq_file *m, pg_data_t *pgdat,
1278 struct zone *zone)
1279 {
1280 int order;
1281
1282 seq_printf(m, "Node %d, zone %8s ", pgdat->node_id, zone->name);
1283 for (order = 0; order < MAX_ORDER; ++order)
1284 seq_printf(m, "%6lu ", zone->free_area[order].nr_free);
1285 seq_putc(m, '\n');
1286 }
1287
1288 /*
1289 * This walks the free areas for each zone.
1290 */
1291 static int frag_show(struct seq_file *m, void *arg)
1292 {
1293 pg_data_t *pgdat = (pg_data_t *)arg;
1294 walk_zones_in_node(m, pgdat, true, false, frag_show_print);
1295 return 0;
1296 }
1297
1298 static void pagetypeinfo_showfree_print(struct seq_file *m,
1299 pg_data_t *pgdat, struct zone *zone)
1300 {
1301 int order, mtype;
1302
1303 for (mtype = 0; mtype < MIGRATE_TYPES; mtype++) {
1304 seq_printf(m, "Node %4d, zone %8s, type %12s ",
1305 pgdat->node_id,
1306 zone->name,
1307 migratetype_names[mtype]);
1308 for (order = 0; order < MAX_ORDER; ++order) {
1309 unsigned long freecount = 0;
1310 struct free_area *area;
1311 struct list_head *curr;
1312
1313 area = &(zone->free_area[order]);
1314
1315 list_for_each(curr, &area->free_list[mtype])
1316 freecount++;
1317 seq_printf(m, "%6lu ", freecount);
1318 }
1319 seq_putc(m, '\n');
1320 }
1321 }
1322
1323 /* Print out the free pages at each order for each migatetype */
1324 static int pagetypeinfo_showfree(struct seq_file *m, void *arg)
1325 {
1326 int order;
1327 pg_data_t *pgdat = (pg_data_t *)arg;
1328
1329 /* Print header */
1330 seq_printf(m, "%-43s ", "Free pages count per migrate type at order");
1331 for (order = 0; order < MAX_ORDER; ++order)
1332 seq_printf(m, "%6d ", order);
1333 seq_putc(m, '\n');
1334
1335 walk_zones_in_node(m, pgdat, true, false, pagetypeinfo_showfree_print);
1336
1337 return 0;
1338 }
1339
1340 static void pagetypeinfo_showblockcount_print(struct seq_file *m,
1341 pg_data_t *pgdat, struct zone *zone)
1342 {
1343 int mtype;
1344 unsigned long pfn;
1345 unsigned long start_pfn = zone->zone_start_pfn;
1346 unsigned long end_pfn = zone_end_pfn(zone);
1347 unsigned long count[MIGRATE_TYPES] = { 0, };
1348
1349 for (pfn = start_pfn; pfn < end_pfn; pfn += pageblock_nr_pages) {
1350 struct page *page;
1351
1352 page = pfn_to_online_page(pfn);
1353 if (!page)
1354 continue;
1355
1356 /* Watch for unexpected holes punched in the memmap */
1357 if (!memmap_valid_within(pfn, page, zone))
1358 continue;
1359
1360 if (page_zone(page) != zone)
1361 continue;
1362
1363 mtype = get_pageblock_migratetype(page);
1364
1365 if (mtype < MIGRATE_TYPES)
1366 count[mtype]++;
1367 }
1368
1369 /* Print counts */
1370 seq_printf(m, "Node %d, zone %8s ", pgdat->node_id, zone->name);
1371 for (mtype = 0; mtype < MIGRATE_TYPES; mtype++)
1372 seq_printf(m, "%12lu ", count[mtype]);
1373 seq_putc(m, '\n');
1374 }
1375
1376 /* Print out the number of pageblocks for each migratetype */
1377 static int pagetypeinfo_showblockcount(struct seq_file *m, void *arg)
1378 {
1379 int mtype;
1380 pg_data_t *pgdat = (pg_data_t *)arg;
1381
1382 seq_printf(m, "\n%-23s", "Number of blocks type ");
1383 for (mtype = 0; mtype < MIGRATE_TYPES; mtype++)
1384 seq_printf(m, "%12s ", migratetype_names[mtype]);
1385 seq_putc(m, '\n');
1386 walk_zones_in_node(m, pgdat, true, false,
1387 pagetypeinfo_showblockcount_print);
1388
1389 return 0;
1390 }
1391
1392 /*
1393 * Print out the number of pageblocks for each migratetype that contain pages
1394 * of other types. This gives an indication of how well fallbacks are being
1395 * contained by rmqueue_fallback(). It requires information from PAGE_OWNER
1396 * to determine what is going on
1397 */
1398 static void pagetypeinfo_showmixedcount(struct seq_file *m, pg_data_t *pgdat)
1399 {
1400 #ifdef CONFIG_PAGE_OWNER
1401 int mtype;
1402
1403 if (!static_branch_unlikely(&page_owner_inited))
1404 return;
1405
1406 drain_all_pages(NULL);
1407
1408 seq_printf(m, "\n%-23s", "Number of mixed blocks ");
1409 for (mtype = 0; mtype < MIGRATE_TYPES; mtype++)
1410 seq_printf(m, "%12s ", migratetype_names[mtype]);
1411 seq_putc(m, '\n');
1412
1413 walk_zones_in_node(m, pgdat, true, true,
1414 pagetypeinfo_showmixedcount_print);
1415 #endif /* CONFIG_PAGE_OWNER */
1416 }
1417
1418 /*
1419 * This prints out statistics in relation to grouping pages by mobility.
1420 * It is expensive to collect so do not constantly read the file.
1421 */
1422 static int pagetypeinfo_show(struct seq_file *m, void *arg)
1423 {
1424 pg_data_t *pgdat = (pg_data_t *)arg;
1425
1426 /* check memoryless node */
1427 if (!node_state(pgdat->node_id, N_MEMORY))
1428 return 0;
1429
1430 seq_printf(m, "Page block order: %d\n", pageblock_order);
1431 seq_printf(m, "Pages per block: %lu\n", pageblock_nr_pages);
1432 seq_putc(m, '\n');
1433 pagetypeinfo_showfree(m, pgdat);
1434 pagetypeinfo_showblockcount(m, pgdat);
1435 pagetypeinfo_showmixedcount(m, pgdat);
1436
1437 return 0;
1438 }
1439
1440 static const struct seq_operations fragmentation_op = {
1441 .start = frag_start,
1442 .next = frag_next,
1443 .stop = frag_stop,
1444 .show = frag_show,
1445 };
1446
1447 static int fragmentation_open(struct inode *inode, struct file *file)
1448 {
1449 return seq_open(file, &fragmentation_op);
1450 }
1451
1452 static const struct file_operations buddyinfo_file_operations = {
1453 .open = fragmentation_open,
1454 .read = seq_read,
1455 .llseek = seq_lseek,
1456 .release = seq_release,
1457 };
1458
1459 static const struct seq_operations pagetypeinfo_op = {
1460 .start = frag_start,
1461 .next = frag_next,
1462 .stop = frag_stop,
1463 .show = pagetypeinfo_show,
1464 };
1465
1466 static int pagetypeinfo_open(struct inode *inode, struct file *file)
1467 {
1468 return seq_open(file, &pagetypeinfo_op);
1469 }
1470
1471 static const struct file_operations pagetypeinfo_file_operations = {
1472 .open = pagetypeinfo_open,
1473 .read = seq_read,
1474 .llseek = seq_lseek,
1475 .release = seq_release,
1476 };
1477
1478 static bool is_zone_first_populated(pg_data_t *pgdat, struct zone *zone)
1479 {
1480 int zid;
1481
1482 for (zid = 0; zid < MAX_NR_ZONES; zid++) {
1483 struct zone *compare = &pgdat->node_zones[zid];
1484
1485 if (populated_zone(compare))
1486 return zone == compare;
1487 }
1488
1489 return false;
1490 }
1491
1492 static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat,
1493 struct zone *zone)
1494 {
1495 int i;
1496 seq_printf(m, "Node %d, zone %8s", pgdat->node_id, zone->name);
1497 if (is_zone_first_populated(pgdat, zone)) {
1498 seq_printf(m, "\n per-node stats");
1499 for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) {
1500 seq_printf(m, "\n %-12s %lu",
1501 vmstat_text[i + NR_VM_ZONE_STAT_ITEMS +
1502 NR_VM_NUMA_STAT_ITEMS],
1503 node_page_state(pgdat, i));
1504 }
1505 }
1506 seq_printf(m,
1507 "\n pages free %lu"
1508 "\n min %lu"
1509 "\n low %lu"
1510 "\n high %lu"
1511 "\n spanned %lu"
1512 "\n present %lu"
1513 "\n managed %lu",
1514 zone_page_state(zone, NR_FREE_PAGES),
1515 min_wmark_pages(zone),
1516 low_wmark_pages(zone),
1517 high_wmark_pages(zone),
1518 zone->spanned_pages,
1519 zone->present_pages,
1520 zone->managed_pages);
1521
1522 seq_printf(m,
1523 "\n protection: (%ld",
1524 zone->lowmem_reserve[0]);
1525 for (i = 1; i < ARRAY_SIZE(zone->lowmem_reserve); i++)
1526 seq_printf(m, ", %ld", zone->lowmem_reserve[i]);
1527 seq_putc(m, ')');
1528
1529 /* If unpopulated, no other information is useful */
1530 if (!populated_zone(zone)) {
1531 seq_putc(m, '\n');
1532 return;
1533 }
1534
1535 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
1536 seq_printf(m, "\n %-12s %lu", vmstat_text[i],
1537 zone_page_state(zone, i));
1538
1539 #ifdef CONFIG_NUMA
1540 for (i = 0; i < NR_VM_NUMA_STAT_ITEMS; i++)
1541 seq_printf(m, "\n %-12s %lu",
1542 vmstat_text[i + NR_VM_ZONE_STAT_ITEMS],
1543 zone_numa_state_snapshot(zone, i));
1544 #endif
1545
1546 seq_printf(m, "\n pagesets");
1547 for_each_online_cpu(i) {
1548 struct per_cpu_pageset *pageset;
1549
1550 pageset = per_cpu_ptr(zone->pageset, i);
1551 seq_printf(m,
1552 "\n cpu: %i"
1553 "\n count: %i"
1554 "\n high: %i"
1555 "\n batch: %i",
1556 i,
1557 pageset->pcp.count,
1558 pageset->pcp.high,
1559 pageset->pcp.batch);
1560 #ifdef CONFIG_SMP
1561 seq_printf(m, "\n vm stats threshold: %d",
1562 pageset->stat_threshold);
1563 #endif
1564 }
1565 seq_printf(m,
1566 "\n node_unreclaimable: %u"
1567 "\n start_pfn: %lu"
1568 "\n node_inactive_ratio: %u",
1569 pgdat->kswapd_failures >= MAX_RECLAIM_RETRIES,
1570 zone->zone_start_pfn,
1571 zone->zone_pgdat->inactive_ratio);
1572 seq_putc(m, '\n');
1573 }
1574
1575 /*
1576 * Output information about zones in @pgdat. All zones are printed regardless
1577 * of whether they are populated or not: lowmem_reserve_ratio operates on the
1578 * set of all zones and userspace would not be aware of such zones if they are
1579 * suppressed here (zoneinfo displays the effect of lowmem_reserve_ratio).
1580 */
1581 static int zoneinfo_show(struct seq_file *m, void *arg)
1582 {
1583 pg_data_t *pgdat = (pg_data_t *)arg;
1584 walk_zones_in_node(m, pgdat, false, false, zoneinfo_show_print);
1585 return 0;
1586 }
1587
1588 static const struct seq_operations zoneinfo_op = {
1589 .start = frag_start, /* iterate over all zones. The same as in
1590 * fragmentation. */
1591 .next = frag_next,
1592 .stop = frag_stop,
1593 .show = zoneinfo_show,
1594 };
1595
1596 static int zoneinfo_open(struct inode *inode, struct file *file)
1597 {
1598 return seq_open(file, &zoneinfo_op);
1599 }
1600
1601 static const struct file_operations zoneinfo_file_operations = {
1602 .open = zoneinfo_open,
1603 .read = seq_read,
1604 .llseek = seq_lseek,
1605 .release = seq_release,
1606 };
1607
1608 enum writeback_stat_item {
1609 NR_DIRTY_THRESHOLD,
1610 NR_DIRTY_BG_THRESHOLD,
1611 NR_VM_WRITEBACK_STAT_ITEMS,
1612 };
1613
1614 static void *vmstat_start(struct seq_file *m, loff_t *pos)
1615 {
1616 unsigned long *v;
1617 int i, stat_items_size;
1618
1619 if (*pos >= ARRAY_SIZE(vmstat_text))
1620 return NULL;
1621 stat_items_size = NR_VM_ZONE_STAT_ITEMS * sizeof(unsigned long) +
1622 NR_VM_NUMA_STAT_ITEMS * sizeof(unsigned long) +
1623 NR_VM_NODE_STAT_ITEMS * sizeof(unsigned long) +
1624 NR_VM_WRITEBACK_STAT_ITEMS * sizeof(unsigned long);
1625
1626 #ifdef CONFIG_VM_EVENT_COUNTERS
1627 stat_items_size += sizeof(struct vm_event_state);
1628 #endif
1629
1630 v = kmalloc(stat_items_size, GFP_KERNEL);
1631 m->private = v;
1632 if (!v)
1633 return ERR_PTR(-ENOMEM);
1634 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
1635 v[i] = global_zone_page_state(i);
1636 v += NR_VM_ZONE_STAT_ITEMS;
1637
1638 #ifdef CONFIG_NUMA
1639 for (i = 0; i < NR_VM_NUMA_STAT_ITEMS; i++)
1640 v[i] = global_numa_state(i);
1641 v += NR_VM_NUMA_STAT_ITEMS;
1642 #endif
1643
1644 for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++)
1645 v[i] = global_node_page_state(i);
1646 v += NR_VM_NODE_STAT_ITEMS;
1647
1648 global_dirty_limits(v + NR_DIRTY_BG_THRESHOLD,
1649 v + NR_DIRTY_THRESHOLD);
1650 v += NR_VM_WRITEBACK_STAT_ITEMS;
1651
1652 #ifdef CONFIG_VM_EVENT_COUNTERS
1653 all_vm_events(v);
1654 v[PGPGIN] /= 2; /* sectors -> kbytes */
1655 v[PGPGOUT] /= 2;
1656 #endif
1657 return (unsigned long *)m->private + *pos;
1658 }
1659
1660 static void *vmstat_next(struct seq_file *m, void *arg, loff_t *pos)
1661 {
1662 (*pos)++;
1663 if (*pos >= ARRAY_SIZE(vmstat_text))
1664 return NULL;
1665 return (unsigned long *)m->private + *pos;
1666 }
1667
1668 static int vmstat_show(struct seq_file *m, void *arg)
1669 {
1670 unsigned long *l = arg;
1671 unsigned long off = l - (unsigned long *)m->private;
1672
1673 seq_puts(m, vmstat_text[off]);
1674 seq_put_decimal_ull(m, " ", *l);
1675 seq_putc(m, '\n');
1676 return 0;
1677 }
1678
1679 static void vmstat_stop(struct seq_file *m, void *arg)
1680 {
1681 kfree(m->private);
1682 m->private = NULL;
1683 }
1684
1685 static const struct seq_operations vmstat_op = {
1686 .start = vmstat_start,
1687 .next = vmstat_next,
1688 .stop = vmstat_stop,
1689 .show = vmstat_show,
1690 };
1691
1692 static int vmstat_open(struct inode *inode, struct file *file)
1693 {
1694 return seq_open(file, &vmstat_op);
1695 }
1696
1697 static const struct file_operations vmstat_file_operations = {
1698 .open = vmstat_open,
1699 .read = seq_read,
1700 .llseek = seq_lseek,
1701 .release = seq_release,
1702 };
1703 #endif /* CONFIG_PROC_FS */
1704
1705 #ifdef CONFIG_SMP
1706 static DEFINE_PER_CPU(struct delayed_work, vmstat_work);
1707 int sysctl_stat_interval __read_mostly = HZ;
1708
1709 #ifdef CONFIG_PROC_FS
1710 static void refresh_vm_stats(struct work_struct *work)
1711 {
1712 refresh_cpu_vm_stats(true);
1713 }
1714
1715 int vmstat_refresh(struct ctl_table *table, int write,
1716 void __user *buffer, size_t *lenp, loff_t *ppos)
1717 {
1718 long val;
1719 int err;
1720 int i;
1721
1722 /*
1723 * The regular update, every sysctl_stat_interval, may come later
1724 * than expected: leaving a significant amount in per_cpu buckets.
1725 * This is particularly misleading when checking a quantity of HUGE
1726 * pages, immediately after running a test. /proc/sys/vm/stat_refresh,
1727 * which can equally be echo'ed to or cat'ted from (by root),
1728 * can be used to update the stats just before reading them.
1729 *
1730 * Oh, and since global_zone_page_state() etc. are so careful to hide
1731 * transiently negative values, report an error here if any of
1732 * the stats is negative, so we know to go looking for imbalance.
1733 */
1734 err = schedule_on_each_cpu(refresh_vm_stats);
1735 if (err)
1736 return err;
1737 for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) {
1738 val = atomic_long_read(&vm_zone_stat[i]);
1739 if (val < 0) {
1740 pr_warn("%s: %s %ld\n",
1741 __func__, vmstat_text[i], val);
1742 err = -EINVAL;
1743 }
1744 }
1745 #ifdef CONFIG_NUMA
1746 for (i = 0; i < NR_VM_NUMA_STAT_ITEMS; i++) {
1747 val = atomic_long_read(&vm_numa_stat[i]);
1748 if (val < 0) {
1749 pr_warn("%s: %s %ld\n",
1750 __func__, vmstat_text[i + NR_VM_ZONE_STAT_ITEMS], val);
1751 err = -EINVAL;
1752 }
1753 }
1754 #endif
1755 if (err)
1756 return err;
1757 if (write)
1758 *ppos += *lenp;
1759 else
1760 *lenp = 0;
1761 return 0;
1762 }
1763 #endif /* CONFIG_PROC_FS */
1764
1765 static void vmstat_update(struct work_struct *w)
1766 {
1767 if (refresh_cpu_vm_stats(true)) {
1768 /*
1769 * Counters were updated so we expect more updates
1770 * to occur in the future. Keep on running the
1771 * update worker thread.
1772 */
1773 queue_delayed_work_on(smp_processor_id(), mm_percpu_wq,
1774 this_cpu_ptr(&vmstat_work),
1775 round_jiffies_relative(sysctl_stat_interval));
1776 }
1777 }
1778
1779 /*
1780 * Switch off vmstat processing and then fold all the remaining differentials
1781 * until the diffs stay at zero. The function is used by NOHZ and can only be
1782 * invoked when tick processing is not active.
1783 */
1784 /*
1785 * Check if the diffs for a certain cpu indicate that
1786 * an update is needed.
1787 */
1788 static bool need_update(int cpu)
1789 {
1790 struct zone *zone;
1791
1792 for_each_populated_zone(zone) {
1793 struct per_cpu_pageset *p = per_cpu_ptr(zone->pageset, cpu);
1794
1795 BUILD_BUG_ON(sizeof(p->vm_stat_diff[0]) != 1);
1796 #ifdef CONFIG_NUMA
1797 BUILD_BUG_ON(sizeof(p->vm_numa_stat_diff[0]) != 2);
1798 #endif
1799
1800 /*
1801 * The fast way of checking if there are any vmstat diffs.
1802 * This works because the diffs are byte sized items.
1803 */
1804 if (memchr_inv(p->vm_stat_diff, 0, NR_VM_ZONE_STAT_ITEMS))
1805 return true;
1806 #ifdef CONFIG_NUMA
1807 if (memchr_inv(p->vm_numa_stat_diff, 0, NR_VM_NUMA_STAT_ITEMS))
1808 return true;
1809 #endif
1810 }
1811 return false;
1812 }
1813
1814 /*
1815 * Switch off vmstat processing and then fold all the remaining differentials
1816 * until the diffs stay at zero. The function is used by NOHZ and can only be
1817 * invoked when tick processing is not active.
1818 */
1819 void quiet_vmstat(void)
1820 {
1821 if (system_state != SYSTEM_RUNNING)
1822 return;
1823
1824 if (!delayed_work_pending(this_cpu_ptr(&vmstat_work)))
1825 return;
1826
1827 if (!need_update(smp_processor_id()))
1828 return;
1829
1830 /*
1831 * Just refresh counters and do not care about the pending delayed
1832 * vmstat_update. It doesn't fire that often to matter and canceling
1833 * it would be too expensive from this path.
1834 * vmstat_shepherd will take care about that for us.
1835 */
1836 refresh_cpu_vm_stats(false);
1837 }
1838
1839 /*
1840 * Shepherd worker thread that checks the
1841 * differentials of processors that have their worker
1842 * threads for vm statistics updates disabled because of
1843 * inactivity.
1844 */
1845 static void vmstat_shepherd(struct work_struct *w);
1846
1847 static DECLARE_DEFERRABLE_WORK(shepherd, vmstat_shepherd);
1848
1849 static void vmstat_shepherd(struct work_struct *w)
1850 {
1851 int cpu;
1852
1853 get_online_cpus();
1854 /* Check processors whose vmstat worker threads have been disabled */
1855 for_each_online_cpu(cpu) {
1856 struct delayed_work *dw = &per_cpu(vmstat_work, cpu);
1857
1858 if (!delayed_work_pending(dw) && need_update(cpu))
1859 queue_delayed_work_on(cpu, mm_percpu_wq, dw, 0);
1860 }
1861 put_online_cpus();
1862
1863 schedule_delayed_work(&shepherd,
1864 round_jiffies_relative(sysctl_stat_interval));
1865 }
1866
1867 static void __init start_shepherd_timer(void)
1868 {
1869 int cpu;
1870
1871 for_each_possible_cpu(cpu)
1872 INIT_DEFERRABLE_WORK(per_cpu_ptr(&vmstat_work, cpu),
1873 vmstat_update);
1874
1875 schedule_delayed_work(&shepherd,
1876 round_jiffies_relative(sysctl_stat_interval));
1877 }
1878
1879 static void __init init_cpu_node_state(void)
1880 {
1881 int node;
1882
1883 for_each_online_node(node) {
1884 if (cpumask_weight(cpumask_of_node(node)) > 0)
1885 node_set_state(node, N_CPU);
1886 }
1887 }
1888
1889 static int vmstat_cpu_online(unsigned int cpu)
1890 {
1891 refresh_zone_stat_thresholds();
1892 node_set_state(cpu_to_node(cpu), N_CPU);
1893 return 0;
1894 }
1895
1896 static int vmstat_cpu_down_prep(unsigned int cpu)
1897 {
1898 cancel_delayed_work_sync(&per_cpu(vmstat_work, cpu));
1899 return 0;
1900 }
1901
1902 static int vmstat_cpu_dead(unsigned int cpu)
1903 {
1904 const struct cpumask *node_cpus;
1905 int node;
1906
1907 node = cpu_to_node(cpu);
1908
1909 refresh_zone_stat_thresholds();
1910 node_cpus = cpumask_of_node(node);
1911 if (cpumask_weight(node_cpus) > 0)
1912 return 0;
1913
1914 node_clear_state(node, N_CPU);
1915 return 0;
1916 }
1917
1918 #endif
1919
1920 struct workqueue_struct *mm_percpu_wq;
1921
1922 void __init init_mm_internals(void)
1923 {
1924 int ret __maybe_unused;
1925
1926 mm_percpu_wq = alloc_workqueue("mm_percpu_wq", WQ_MEM_RECLAIM, 0);
1927
1928 #ifdef CONFIG_SMP
1929 ret = cpuhp_setup_state_nocalls(CPUHP_MM_VMSTAT_DEAD, "mm/vmstat:dead",
1930 NULL, vmstat_cpu_dead);
1931 if (ret < 0)
1932 pr_err("vmstat: failed to register 'dead' hotplug state\n");
1933
1934 ret = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "mm/vmstat:online",
1935 vmstat_cpu_online,
1936 vmstat_cpu_down_prep);
1937 if (ret < 0)
1938 pr_err("vmstat: failed to register 'online' hotplug state\n");
1939
1940 get_online_cpus();
1941 init_cpu_node_state();
1942 put_online_cpus();
1943
1944 start_shepherd_timer();
1945 #endif
1946 #ifdef CONFIG_PROC_FS
1947 proc_create("buddyinfo", 0444, NULL, &buddyinfo_file_operations);
1948 proc_create("pagetypeinfo", 0444, NULL, &pagetypeinfo_file_operations);
1949 proc_create("vmstat", 0444, NULL, &vmstat_file_operations);
1950 proc_create("zoneinfo", 0444, NULL, &zoneinfo_file_operations);
1951 #endif
1952 }
1953
1954 #if defined(CONFIG_DEBUG_FS) && defined(CONFIG_COMPACTION)
1955
1956 /*
1957 * Return an index indicating how much of the available free memory is
1958 * unusable for an allocation of the requested size.
1959 */
1960 static int unusable_free_index(unsigned int order,
1961 struct contig_page_info *info)
1962 {
1963 /* No free memory is interpreted as all free memory is unusable */
1964 if (info->free_pages == 0)
1965 return 1000;
1966
1967 /*
1968 * Index should be a value between 0 and 1. Return a value to 3
1969 * decimal places.
1970 *
1971 * 0 => no fragmentation
1972 * 1 => high fragmentation
1973 */
1974 return div_u64((info->free_pages - (info->free_blocks_suitable << order)) * 1000ULL, info->free_pages);
1975
1976 }
1977
1978 static void unusable_show_print(struct seq_file *m,
1979 pg_data_t *pgdat, struct zone *zone)
1980 {
1981 unsigned int order;
1982 int index;
1983 struct contig_page_info info;
1984
1985 seq_printf(m, "Node %d, zone %8s ",
1986 pgdat->node_id,
1987 zone->name);
1988 for (order = 0; order < MAX_ORDER; ++order) {
1989 fill_contig_page_info(zone, order, &info);
1990 index = unusable_free_index(order, &info);
1991 seq_printf(m, "%d.%03d ", index / 1000, index % 1000);
1992 }
1993
1994 seq_putc(m, '\n');
1995 }
1996
1997 /*
1998 * Display unusable free space index
1999 *
2000 * The unusable free space index measures how much of the available free
2001 * memory cannot be used to satisfy an allocation of a given size and is a
2002 * value between 0 and 1. The higher the value, the more of free memory is
2003 * unusable and by implication, the worse the external fragmentation is. This
2004 * can be expressed as a percentage by multiplying by 100.
2005 */
2006 static int unusable_show(struct seq_file *m, void *arg)
2007 {
2008 pg_data_t *pgdat = (pg_data_t *)arg;
2009
2010 /* check memoryless node */
2011 if (!node_state(pgdat->node_id, N_MEMORY))
2012 return 0;
2013
2014 walk_zones_in_node(m, pgdat, true, false, unusable_show_print);
2015
2016 return 0;
2017 }
2018
2019 static const struct seq_operations unusable_op = {
2020 .start = frag_start,
2021 .next = frag_next,
2022 .stop = frag_stop,
2023 .show = unusable_show,
2024 };
2025
2026 static int unusable_open(struct inode *inode, struct file *file)
2027 {
2028 return seq_open(file, &unusable_op);
2029 }
2030
2031 static const struct file_operations unusable_file_ops = {
2032 .open = unusable_open,
2033 .read = seq_read,
2034 .llseek = seq_lseek,
2035 .release = seq_release,
2036 };
2037
2038 static void extfrag_show_print(struct seq_file *m,
2039 pg_data_t *pgdat, struct zone *zone)
2040 {
2041 unsigned int order;
2042 int index;
2043
2044 /* Alloc on stack as interrupts are disabled for zone walk */
2045 struct contig_page_info info;
2046
2047 seq_printf(m, "Node %d, zone %8s ",
2048 pgdat->node_id,
2049 zone->name);
2050 for (order = 0; order < MAX_ORDER; ++order) {
2051 fill_contig_page_info(zone, order, &info);
2052 index = __fragmentation_index(order, &info);
2053 seq_printf(m, "%d.%03d ", index / 1000, index % 1000);
2054 }
2055
2056 seq_putc(m, '\n');
2057 }
2058
2059 /*
2060 * Display fragmentation index for orders that allocations would fail for
2061 */
2062 static int extfrag_show(struct seq_file *m, void *arg)
2063 {
2064 pg_data_t *pgdat = (pg_data_t *)arg;
2065
2066 walk_zones_in_node(m, pgdat, true, false, extfrag_show_print);
2067
2068 return 0;
2069 }
2070
2071 static const struct seq_operations extfrag_op = {
2072 .start = frag_start,
2073 .next = frag_next,
2074 .stop = frag_stop,
2075 .show = extfrag_show,
2076 };
2077
2078 static int extfrag_open(struct inode *inode, struct file *file)
2079 {
2080 return seq_open(file, &extfrag_op);
2081 }
2082
2083 static const struct file_operations extfrag_file_ops = {
2084 .open = extfrag_open,
2085 .read = seq_read,
2086 .llseek = seq_lseek,
2087 .release = seq_release,
2088 };
2089
2090 static int __init extfrag_debug_init(void)
2091 {
2092 struct dentry *extfrag_debug_root;
2093
2094 extfrag_debug_root = debugfs_create_dir("extfrag", NULL);
2095 if (!extfrag_debug_root)
2096 return -ENOMEM;
2097
2098 if (!debugfs_create_file("unusable_index", 0444,
2099 extfrag_debug_root, NULL, &unusable_file_ops))
2100 goto fail;
2101
2102 if (!debugfs_create_file("extfrag_index", 0444,
2103 extfrag_debug_root, NULL, &extfrag_file_ops))
2104 goto fail;
2105
2106 return 0;
2107 fail:
2108 debugfs_remove_recursive(extfrag_debug_root);
2109 return -ENOMEM;
2110 }
2111
2112 module_init(extfrag_debug_init);
2113 #endif