1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * linux/mm/vmstat.c |
4 | * |
5 | * Manages VM statistics |
6 | * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds |
7 | * |
8 | * zoned VM statistics |
9 | * Copyright (C) 2006 Silicon Graphics, Inc., |
10 | * Christoph Lameter <christoph@lameter.com> |
11 | * Copyright (C) 2008-2014 Christoph Lameter |
12 | */ |
13 | #include <linux/fs.h> |
14 | #include <linux/mm.h> |
15 | #include <linux/err.h> |
16 | #include <linux/module.h> |
17 | #include <linux/slab.h> |
18 | #include <linux/cpu.h> |
19 | #include <linux/cpumask.h> |
20 | #include <linux/vmstat.h> |
21 | #include <linux/proc_fs.h> |
22 | #include <linux/seq_file.h> |
23 | #include <linux/debugfs.h> |
24 | #include <linux/sched.h> |
25 | #include <linux/math64.h> |
26 | #include <linux/writeback.h> |
27 | #include <linux/compaction.h> |
28 | #include <linux/mm_inline.h> |
29 | #include <linux/page_owner.h> |
30 | #include <linux/sched/isolation.h> |
31 | |
32 | #include "internal.h" |
33 | |
34 | #ifdef CONFIG_NUMA |
35 | int sysctl_vm_numa_stat = ENABLE_NUMA_STAT; |
36 | |
37 | /* zero numa counters within a zone */ |
38 | static void zero_zone_numa_counters(struct zone *zone) |
39 | { |
40 | int item, cpu; |
41 | |
42 | for (item = 0; item < NR_VM_NUMA_EVENT_ITEMS; item++) { |
43 | atomic_long_set(v: &zone->vm_numa_event[item], i: 0); |
44 | for_each_online_cpu(cpu) { |
45 | per_cpu_ptr(zone->per_cpu_zonestats, cpu)->vm_numa_event[item] |
46 | = 0; |
47 | } |
48 | } |
49 | } |
50 | |
51 | /* zero numa counters of all the populated zones */ |
52 | static void zero_zones_numa_counters(void) |
53 | { |
54 | struct zone *zone; |
55 | |
56 | for_each_populated_zone(zone) |
57 | zero_zone_numa_counters(zone); |
58 | } |
59 | |
60 | /* zero global numa counters */ |
61 | static void zero_global_numa_counters(void) |
62 | { |
63 | int item; |
64 | |
65 | for (item = 0; item < NR_VM_NUMA_EVENT_ITEMS; item++) |
66 | atomic_long_set(v: &vm_numa_event[item], i: 0); |
67 | } |
68 | |
69 | static void invalid_numa_statistics(void) |
70 | { |
71 | zero_zones_numa_counters(); |
72 | zero_global_numa_counters(); |
73 | } |
74 | |
75 | static DEFINE_MUTEX(vm_numa_stat_lock); |
76 | |
77 | int sysctl_vm_numa_stat_handler(struct ctl_table *table, int write, |
78 | void *buffer, size_t *length, loff_t *ppos) |
79 | { |
80 | int ret, oldval; |
81 | |
82 | mutex_lock(&vm_numa_stat_lock); |
83 | if (write) |
84 | oldval = sysctl_vm_numa_stat; |
85 | ret = proc_dointvec_minmax(table, write, buffer, length, ppos); |
86 | if (ret || !write) |
87 | goto out; |
88 | |
89 | if (oldval == sysctl_vm_numa_stat) |
90 | goto out; |
91 | else if (sysctl_vm_numa_stat == ENABLE_NUMA_STAT) { |
92 | static_branch_enable(&vm_numa_stat_key); |
93 | pr_info("enable numa statistics\n" ); |
94 | } else { |
95 | static_branch_disable(&vm_numa_stat_key); |
96 | invalid_numa_statistics(); |
97 | pr_info("disable numa statistics, and clear numa counters\n" ); |
98 | } |
99 | |
100 | out: |
101 | mutex_unlock(lock: &vm_numa_stat_lock); |
102 | return ret; |
103 | } |
104 | #endif |
105 | |
106 | #ifdef CONFIG_VM_EVENT_COUNTERS |
107 | DEFINE_PER_CPU(struct vm_event_state, vm_event_states) = {{0}}; |
108 | EXPORT_PER_CPU_SYMBOL(vm_event_states); |
109 | |
110 | static void sum_vm_events(unsigned long *ret) |
111 | { |
112 | int cpu; |
113 | int i; |
114 | |
115 | memset(ret, 0, NR_VM_EVENT_ITEMS * sizeof(unsigned long)); |
116 | |
117 | for_each_online_cpu(cpu) { |
118 | struct vm_event_state *this = &per_cpu(vm_event_states, cpu); |
119 | |
120 | for (i = 0; i < NR_VM_EVENT_ITEMS; i++) |
121 | ret[i] += this->event[i]; |
122 | } |
123 | } |
124 | |
125 | /* |
126 | * Accumulate the vm event counters across all CPUs. |
127 | * The result is unavoidably approximate - it can change |
128 | * during and after execution of this function. |
129 | */ |
130 | void all_vm_events(unsigned long *ret) |
131 | { |
132 | cpus_read_lock(); |
133 | sum_vm_events(ret); |
134 | cpus_read_unlock(); |
135 | } |
136 | EXPORT_SYMBOL_GPL(all_vm_events); |
137 | |
138 | /* |
139 | * Fold the foreign cpu events into our own. |
140 | * |
141 | * This is adding to the events on one processor |
142 | * but keeps the global counts constant. |
143 | */ |
144 | void vm_events_fold_cpu(int cpu) |
145 | { |
146 | struct vm_event_state *fold_state = &per_cpu(vm_event_states, cpu); |
147 | int i; |
148 | |
149 | for (i = 0; i < NR_VM_EVENT_ITEMS; i++) { |
150 | count_vm_events(item: i, delta: fold_state->event[i]); |
151 | fold_state->event[i] = 0; |
152 | } |
153 | } |
154 | |
155 | #endif /* CONFIG_VM_EVENT_COUNTERS */ |
156 | |
157 | /* |
158 | * Manage combined zone based / global counters |
159 | * |
160 | * vm_stat contains the global counters |
161 | */ |
162 | atomic_long_t vm_zone_stat[NR_VM_ZONE_STAT_ITEMS] __cacheline_aligned_in_smp; |
163 | atomic_long_t vm_node_stat[NR_VM_NODE_STAT_ITEMS] __cacheline_aligned_in_smp; |
164 | atomic_long_t vm_numa_event[NR_VM_NUMA_EVENT_ITEMS] __cacheline_aligned_in_smp; |
165 | EXPORT_SYMBOL(vm_zone_stat); |
166 | EXPORT_SYMBOL(vm_node_stat); |
167 | |
168 | #ifdef CONFIG_NUMA |
169 | static void fold_vm_zone_numa_events(struct zone *zone) |
170 | { |
171 | unsigned long zone_numa_events[NR_VM_NUMA_EVENT_ITEMS] = { 0, }; |
172 | int cpu; |
173 | enum numa_stat_item item; |
174 | |
175 | for_each_online_cpu(cpu) { |
176 | struct per_cpu_zonestat *pzstats; |
177 | |
178 | pzstats = per_cpu_ptr(zone->per_cpu_zonestats, cpu); |
179 | for (item = 0; item < NR_VM_NUMA_EVENT_ITEMS; item++) |
180 | zone_numa_events[item] += xchg(&pzstats->vm_numa_event[item], 0); |
181 | } |
182 | |
183 | for (item = 0; item < NR_VM_NUMA_EVENT_ITEMS; item++) |
184 | zone_numa_event_add(x: zone_numa_events[item], zone, item); |
185 | } |
186 | |
187 | void fold_vm_numa_events(void) |
188 | { |
189 | struct zone *zone; |
190 | |
191 | for_each_populated_zone(zone) |
192 | fold_vm_zone_numa_events(zone); |
193 | } |
194 | #endif |
195 | |
196 | #ifdef CONFIG_SMP |
197 | |
198 | int calculate_pressure_threshold(struct zone *zone) |
199 | { |
200 | int threshold; |
201 | int watermark_distance; |
202 | |
203 | /* |
204 | * As vmstats are not up to date, there is drift between the estimated |
205 | * and real values. For high thresholds and a high number of CPUs, it |
206 | * is possible for the min watermark to be breached while the estimated |
207 | * value looks fine. The pressure threshold is a reduced value such |
208 | * that even the maximum amount of drift will not accidentally breach |
209 | * the min watermark |
210 | */ |
211 | watermark_distance = low_wmark_pages(zone) - min_wmark_pages(zone); |
212 | threshold = max(1, (int)(watermark_distance / num_online_cpus())); |
213 | |
214 | /* |
215 | * Maximum threshold is 125 |
216 | */ |
217 | threshold = min(125, threshold); |
218 | |
219 | return threshold; |
220 | } |
221 | |
222 | int calculate_normal_threshold(struct zone *zone) |
223 | { |
224 | int threshold; |
225 | int mem; /* memory in 128 MB units */ |
226 | |
227 | /* |
228 | * The threshold scales with the number of processors and the amount |
229 | * of memory per zone. More memory means that we can defer updates for |
230 | * longer, more processors could lead to more contention. |
231 | * fls() is used to have a cheap way of logarithmic scaling. |
232 | * |
233 | * Some sample thresholds: |
234 | * |
235 | * Threshold Processors (fls) Zonesize fls(mem)+1 |
236 | * ------------------------------------------------------------------ |
237 | * 8 1 1 0.9-1 GB 4 |
238 | * 16 2 2 0.9-1 GB 4 |
239 | * 20 2 2 1-2 GB 5 |
240 | * 24 2 2 2-4 GB 6 |
241 | * 28 2 2 4-8 GB 7 |
242 | * 32 2 2 8-16 GB 8 |
243 | * 4 2 2 <128M 1 |
244 | * 30 4 3 2-4 GB 5 |
245 | * 48 4 3 8-16 GB 8 |
246 | * 32 8 4 1-2 GB 4 |
247 | * 32 8 4 0.9-1GB 4 |
248 | * 10 16 5 <128M 1 |
249 | * 40 16 5 900M 4 |
250 | * 70 64 7 2-4 GB 5 |
251 | * 84 64 7 4-8 GB 6 |
252 | * 108 512 9 4-8 GB 6 |
253 | * 125 1024 10 8-16 GB 8 |
254 | * 125 1024 10 16-32 GB 9 |
255 | */ |
256 | |
257 | mem = zone_managed_pages(zone) >> (27 - PAGE_SHIFT); |
258 | |
259 | threshold = 2 * fls(x: num_online_cpus()) * (1 + fls(x: mem)); |
260 | |
261 | /* |
262 | * Maximum threshold is 125 |
263 | */ |
264 | threshold = min(125, threshold); |
265 | |
266 | return threshold; |
267 | } |
268 | |
269 | /* |
270 | * Refresh the thresholds for each zone. |
271 | */ |
272 | void refresh_zone_stat_thresholds(void) |
273 | { |
274 | struct pglist_data *pgdat; |
275 | struct zone *zone; |
276 | int cpu; |
277 | int threshold; |
278 | |
279 | /* Zero current pgdat thresholds */ |
280 | for_each_online_pgdat(pgdat) { |
281 | for_each_online_cpu(cpu) { |
282 | per_cpu_ptr(pgdat->per_cpu_nodestats, cpu)->stat_threshold = 0; |
283 | } |
284 | } |
285 | |
286 | for_each_populated_zone(zone) { |
287 | struct pglist_data *pgdat = zone->zone_pgdat; |
288 | unsigned long max_drift, tolerate_drift; |
289 | |
290 | threshold = calculate_normal_threshold(zone); |
291 | |
292 | for_each_online_cpu(cpu) { |
293 | int pgdat_threshold; |
294 | |
295 | per_cpu_ptr(zone->per_cpu_zonestats, cpu)->stat_threshold |
296 | = threshold; |
297 | |
298 | /* Base nodestat threshold on the largest populated zone. */ |
299 | pgdat_threshold = per_cpu_ptr(pgdat->per_cpu_nodestats, cpu)->stat_threshold; |
300 | per_cpu_ptr(pgdat->per_cpu_nodestats, cpu)->stat_threshold |
301 | = max(threshold, pgdat_threshold); |
302 | } |
303 | |
304 | /* |
305 | * Only set percpu_drift_mark if there is a danger that |
306 | * NR_FREE_PAGES reports the low watermark is ok when in fact |
307 | * the min watermark could be breached by an allocation |
308 | */ |
309 | tolerate_drift = low_wmark_pages(zone) - min_wmark_pages(zone); |
310 | max_drift = num_online_cpus() * threshold; |
311 | if (max_drift > tolerate_drift) |
312 | zone->percpu_drift_mark = high_wmark_pages(zone) + |
313 | max_drift; |
314 | } |
315 | } |
316 | |
317 | void set_pgdat_percpu_threshold(pg_data_t *pgdat, |
318 | int (*calculate_pressure)(struct zone *)) |
319 | { |
320 | struct zone *zone; |
321 | int cpu; |
322 | int threshold; |
323 | int i; |
324 | |
325 | for (i = 0; i < pgdat->nr_zones; i++) { |
326 | zone = &pgdat->node_zones[i]; |
327 | if (!zone->percpu_drift_mark) |
328 | continue; |
329 | |
330 | threshold = (*calculate_pressure)(zone); |
331 | for_each_online_cpu(cpu) |
332 | per_cpu_ptr(zone->per_cpu_zonestats, cpu)->stat_threshold |
333 | = threshold; |
334 | } |
335 | } |
336 | |
337 | /* |
338 | * For use when we know that interrupts are disabled, |
339 | * or when we know that preemption is disabled and that |
340 | * particular counter cannot be updated from interrupt context. |
341 | */ |
342 | void __mod_zone_page_state(struct zone *zone, enum zone_stat_item item, |
343 | long delta) |
344 | { |
345 | struct per_cpu_zonestat __percpu *pcp = zone->per_cpu_zonestats; |
346 | s8 __percpu *p = pcp->vm_stat_diff + item; |
347 | long x; |
348 | long t; |
349 | |
350 | /* |
351 | * Accurate vmstat updates require a RMW. On !PREEMPT_RT kernels, |
352 | * atomicity is provided by IRQs being disabled -- either explicitly |
353 | * or via local_lock_irq. On PREEMPT_RT, local_lock_irq only disables |
354 | * CPU migrations and preemption potentially corrupts a counter so |
355 | * disable preemption. |
356 | */ |
357 | preempt_disable_nested(); |
358 | |
359 | x = delta + __this_cpu_read(*p); |
360 | |
361 | t = __this_cpu_read(pcp->stat_threshold); |
362 | |
363 | if (unlikely(abs(x) > t)) { |
364 | zone_page_state_add(x, zone, item); |
365 | x = 0; |
366 | } |
367 | __this_cpu_write(*p, x); |
368 | |
369 | preempt_enable_nested(); |
370 | } |
371 | EXPORT_SYMBOL(__mod_zone_page_state); |
372 | |
373 | void __mod_node_page_state(struct pglist_data *pgdat, enum node_stat_item item, |
374 | long delta) |
375 | { |
376 | struct per_cpu_nodestat __percpu *pcp = pgdat->per_cpu_nodestats; |
377 | s8 __percpu *p = pcp->vm_node_stat_diff + item; |
378 | long x; |
379 | long t; |
380 | |
381 | if (vmstat_item_in_bytes(idx: item)) { |
382 | /* |
383 | * Only cgroups use subpage accounting right now; at |
384 | * the global level, these items still change in |
385 | * multiples of whole pages. Store them as pages |
386 | * internally to keep the per-cpu counters compact. |
387 | */ |
388 | VM_WARN_ON_ONCE(delta & (PAGE_SIZE - 1)); |
389 | delta >>= PAGE_SHIFT; |
390 | } |
391 | |
392 | /* See __mod_node_page_state */ |
393 | preempt_disable_nested(); |
394 | |
395 | x = delta + __this_cpu_read(*p); |
396 | |
397 | t = __this_cpu_read(pcp->stat_threshold); |
398 | |
399 | if (unlikely(abs(x) > t)) { |
400 | node_page_state_add(x, pgdat, item); |
401 | x = 0; |
402 | } |
403 | __this_cpu_write(*p, x); |
404 | |
405 | preempt_enable_nested(); |
406 | } |
407 | EXPORT_SYMBOL(__mod_node_page_state); |
408 | |
409 | /* |
410 | * Optimized increment and decrement functions. |
411 | * |
412 | * These are only for a single page and therefore can take a struct page * |
413 | * argument instead of struct zone *. This allows the inclusion of the code |
414 | * generated for page_zone(page) into the optimized functions. |
415 | * |
416 | * No overflow check is necessary and therefore the differential can be |
417 | * incremented or decremented in place which may allow the compilers to |
418 | * generate better code. |
419 | * The increment or decrement is known and therefore one boundary check can |
420 | * be omitted. |
421 | * |
422 | * NOTE: These functions are very performance sensitive. Change only |
423 | * with care. |
424 | * |
425 | * Some processors have inc/dec instructions that are atomic vs an interrupt. |
426 | * However, the code must first determine the differential location in a zone |
427 | * based on the processor number and then inc/dec the counter. There is no |
428 | * guarantee without disabling preemption that the processor will not change |
429 | * in between and therefore the atomicity vs. interrupt cannot be exploited |
430 | * in a useful way here. |
431 | */ |
432 | void __inc_zone_state(struct zone *zone, enum zone_stat_item item) |
433 | { |
434 | struct per_cpu_zonestat __percpu *pcp = zone->per_cpu_zonestats; |
435 | s8 __percpu *p = pcp->vm_stat_diff + item; |
436 | s8 v, t; |
437 | |
438 | /* See __mod_node_page_state */ |
439 | preempt_disable_nested(); |
440 | |
441 | v = __this_cpu_inc_return(*p); |
442 | t = __this_cpu_read(pcp->stat_threshold); |
443 | if (unlikely(v > t)) { |
444 | s8 overstep = t >> 1; |
445 | |
446 | zone_page_state_add(x: v + overstep, zone, item); |
447 | __this_cpu_write(*p, -overstep); |
448 | } |
449 | |
450 | preempt_enable_nested(); |
451 | } |
452 | |
453 | void __inc_node_state(struct pglist_data *pgdat, enum node_stat_item item) |
454 | { |
455 | struct per_cpu_nodestat __percpu *pcp = pgdat->per_cpu_nodestats; |
456 | s8 __percpu *p = pcp->vm_node_stat_diff + item; |
457 | s8 v, t; |
458 | |
459 | VM_WARN_ON_ONCE(vmstat_item_in_bytes(item)); |
460 | |
461 | /* See __mod_node_page_state */ |
462 | preempt_disable_nested(); |
463 | |
464 | v = __this_cpu_inc_return(*p); |
465 | t = __this_cpu_read(pcp->stat_threshold); |
466 | if (unlikely(v > t)) { |
467 | s8 overstep = t >> 1; |
468 | |
469 | node_page_state_add(x: v + overstep, pgdat, item); |
470 | __this_cpu_write(*p, -overstep); |
471 | } |
472 | |
473 | preempt_enable_nested(); |
474 | } |
475 | |
476 | void __inc_zone_page_state(struct page *page, enum zone_stat_item item) |
477 | { |
478 | __inc_zone_state(zone: page_zone(page), item); |
479 | } |
480 | EXPORT_SYMBOL(__inc_zone_page_state); |
481 | |
482 | void __inc_node_page_state(struct page *page, enum node_stat_item item) |
483 | { |
484 | __inc_node_state(pgdat: page_pgdat(page), item); |
485 | } |
486 | EXPORT_SYMBOL(__inc_node_page_state); |
487 | |
488 | void __dec_zone_state(struct zone *zone, enum zone_stat_item item) |
489 | { |
490 | struct per_cpu_zonestat __percpu *pcp = zone->per_cpu_zonestats; |
491 | s8 __percpu *p = pcp->vm_stat_diff + item; |
492 | s8 v, t; |
493 | |
494 | /* See __mod_node_page_state */ |
495 | preempt_disable_nested(); |
496 | |
497 | v = __this_cpu_dec_return(*p); |
498 | t = __this_cpu_read(pcp->stat_threshold); |
499 | if (unlikely(v < - t)) { |
500 | s8 overstep = t >> 1; |
501 | |
502 | zone_page_state_add(x: v - overstep, zone, item); |
503 | __this_cpu_write(*p, overstep); |
504 | } |
505 | |
506 | preempt_enable_nested(); |
507 | } |
508 | |
509 | void __dec_node_state(struct pglist_data *pgdat, enum node_stat_item item) |
510 | { |
511 | struct per_cpu_nodestat __percpu *pcp = pgdat->per_cpu_nodestats; |
512 | s8 __percpu *p = pcp->vm_node_stat_diff + item; |
513 | s8 v, t; |
514 | |
515 | VM_WARN_ON_ONCE(vmstat_item_in_bytes(item)); |
516 | |
517 | /* See __mod_node_page_state */ |
518 | preempt_disable_nested(); |
519 | |
520 | v = __this_cpu_dec_return(*p); |
521 | t = __this_cpu_read(pcp->stat_threshold); |
522 | if (unlikely(v < - t)) { |
523 | s8 overstep = t >> 1; |
524 | |
525 | node_page_state_add(x: v - overstep, pgdat, item); |
526 | __this_cpu_write(*p, overstep); |
527 | } |
528 | |
529 | preempt_enable_nested(); |
530 | } |
531 | |
532 | void __dec_zone_page_state(struct page *page, enum zone_stat_item item) |
533 | { |
534 | __dec_zone_state(zone: page_zone(page), item); |
535 | } |
536 | EXPORT_SYMBOL(__dec_zone_page_state); |
537 | |
538 | void __dec_node_page_state(struct page *page, enum node_stat_item item) |
539 | { |
540 | __dec_node_state(pgdat: page_pgdat(page), item); |
541 | } |
542 | EXPORT_SYMBOL(__dec_node_page_state); |
543 | |
544 | #ifdef CONFIG_HAVE_CMPXCHG_LOCAL |
545 | /* |
546 | * If we have cmpxchg_local support then we do not need to incur the overhead |
547 | * that comes with local_irq_save/restore if we use this_cpu_cmpxchg. |
548 | * |
549 | * mod_state() modifies the zone counter state through atomic per cpu |
550 | * operations. |
551 | * |
552 | * Overstep mode specifies how overstep should handled: |
553 | * 0 No overstepping |
554 | * 1 Overstepping half of threshold |
555 | * -1 Overstepping minus half of threshold |
556 | */ |
557 | static inline void mod_zone_state(struct zone *zone, |
558 | enum zone_stat_item item, long delta, int overstep_mode) |
559 | { |
560 | struct per_cpu_zonestat __percpu *pcp = zone->per_cpu_zonestats; |
561 | s8 __percpu *p = pcp->vm_stat_diff + item; |
562 | long n, t, z; |
563 | s8 o; |
564 | |
565 | o = this_cpu_read(*p); |
566 | do { |
567 | z = 0; /* overflow to zone counters */ |
568 | |
569 | /* |
570 | * The fetching of the stat_threshold is racy. We may apply |
571 | * a counter threshold to the wrong the cpu if we get |
572 | * rescheduled while executing here. However, the next |
573 | * counter update will apply the threshold again and |
574 | * therefore bring the counter under the threshold again. |
575 | * |
576 | * Most of the time the thresholds are the same anyways |
577 | * for all cpus in a zone. |
578 | */ |
579 | t = this_cpu_read(pcp->stat_threshold); |
580 | |
581 | n = delta + (long)o; |
582 | |
583 | if (abs(n) > t) { |
584 | int os = overstep_mode * (t >> 1) ; |
585 | |
586 | /* Overflow must be added to zone counters */ |
587 | z = n + os; |
588 | n = -os; |
589 | } |
590 | } while (!this_cpu_try_cmpxchg(*p, &o, n)); |
591 | |
592 | if (z) |
593 | zone_page_state_add(x: z, zone, item); |
594 | } |
595 | |
596 | void mod_zone_page_state(struct zone *zone, enum zone_stat_item item, |
597 | long delta) |
598 | { |
599 | mod_zone_state(zone, item, delta, overstep_mode: 0); |
600 | } |
601 | EXPORT_SYMBOL(mod_zone_page_state); |
602 | |
603 | void inc_zone_page_state(struct page *page, enum zone_stat_item item) |
604 | { |
605 | mod_zone_state(zone: page_zone(page), item, delta: 1, overstep_mode: 1); |
606 | } |
607 | EXPORT_SYMBOL(inc_zone_page_state); |
608 | |
609 | void dec_zone_page_state(struct page *page, enum zone_stat_item item) |
610 | { |
611 | mod_zone_state(zone: page_zone(page), item, delta: -1, overstep_mode: -1); |
612 | } |
613 | EXPORT_SYMBOL(dec_zone_page_state); |
614 | |
615 | static inline void mod_node_state(struct pglist_data *pgdat, |
616 | enum node_stat_item item, int delta, int overstep_mode) |
617 | { |
618 | struct per_cpu_nodestat __percpu *pcp = pgdat->per_cpu_nodestats; |
619 | s8 __percpu *p = pcp->vm_node_stat_diff + item; |
620 | long n, t, z; |
621 | s8 o; |
622 | |
623 | if (vmstat_item_in_bytes(idx: item)) { |
624 | /* |
625 | * Only cgroups use subpage accounting right now; at |
626 | * the global level, these items still change in |
627 | * multiples of whole pages. Store them as pages |
628 | * internally to keep the per-cpu counters compact. |
629 | */ |
630 | VM_WARN_ON_ONCE(delta & (PAGE_SIZE - 1)); |
631 | delta >>= PAGE_SHIFT; |
632 | } |
633 | |
634 | o = this_cpu_read(*p); |
635 | do { |
636 | z = 0; /* overflow to node counters */ |
637 | |
638 | /* |
639 | * The fetching of the stat_threshold is racy. We may apply |
640 | * a counter threshold to the wrong the cpu if we get |
641 | * rescheduled while executing here. However, the next |
642 | * counter update will apply the threshold again and |
643 | * therefore bring the counter under the threshold again. |
644 | * |
645 | * Most of the time the thresholds are the same anyways |
646 | * for all cpus in a node. |
647 | */ |
648 | t = this_cpu_read(pcp->stat_threshold); |
649 | |
650 | n = delta + (long)o; |
651 | |
652 | if (abs(n) > t) { |
653 | int os = overstep_mode * (t >> 1) ; |
654 | |
655 | /* Overflow must be added to node counters */ |
656 | z = n + os; |
657 | n = -os; |
658 | } |
659 | } while (!this_cpu_try_cmpxchg(*p, &o, n)); |
660 | |
661 | if (z) |
662 | node_page_state_add(x: z, pgdat, item); |
663 | } |
664 | |
665 | void mod_node_page_state(struct pglist_data *pgdat, enum node_stat_item item, |
666 | long delta) |
667 | { |
668 | mod_node_state(pgdat, item, delta, overstep_mode: 0); |
669 | } |
670 | EXPORT_SYMBOL(mod_node_page_state); |
671 | |
672 | void inc_node_state(struct pglist_data *pgdat, enum node_stat_item item) |
673 | { |
674 | mod_node_state(pgdat, item, delta: 1, overstep_mode: 1); |
675 | } |
676 | |
677 | void inc_node_page_state(struct page *page, enum node_stat_item item) |
678 | { |
679 | mod_node_state(pgdat: page_pgdat(page), item, delta: 1, overstep_mode: 1); |
680 | } |
681 | EXPORT_SYMBOL(inc_node_page_state); |
682 | |
683 | void dec_node_page_state(struct page *page, enum node_stat_item item) |
684 | { |
685 | mod_node_state(pgdat: page_pgdat(page), item, delta: -1, overstep_mode: -1); |
686 | } |
687 | EXPORT_SYMBOL(dec_node_page_state); |
688 | #else |
689 | /* |
690 | * Use interrupt disable to serialize counter updates |
691 | */ |
692 | void mod_zone_page_state(struct zone *zone, enum zone_stat_item item, |
693 | long delta) |
694 | { |
695 | unsigned long flags; |
696 | |
697 | local_irq_save(flags); |
698 | __mod_zone_page_state(zone, item, delta); |
699 | local_irq_restore(flags); |
700 | } |
701 | EXPORT_SYMBOL(mod_zone_page_state); |
702 | |
703 | void inc_zone_page_state(struct page *page, enum zone_stat_item item) |
704 | { |
705 | unsigned long flags; |
706 | struct zone *zone; |
707 | |
708 | zone = page_zone(page); |
709 | local_irq_save(flags); |
710 | __inc_zone_state(zone, item); |
711 | local_irq_restore(flags); |
712 | } |
713 | EXPORT_SYMBOL(inc_zone_page_state); |
714 | |
715 | void dec_zone_page_state(struct page *page, enum zone_stat_item item) |
716 | { |
717 | unsigned long flags; |
718 | |
719 | local_irq_save(flags); |
720 | __dec_zone_page_state(page, item); |
721 | local_irq_restore(flags); |
722 | } |
723 | EXPORT_SYMBOL(dec_zone_page_state); |
724 | |
725 | void inc_node_state(struct pglist_data *pgdat, enum node_stat_item item) |
726 | { |
727 | unsigned long flags; |
728 | |
729 | local_irq_save(flags); |
730 | __inc_node_state(pgdat, item); |
731 | local_irq_restore(flags); |
732 | } |
733 | EXPORT_SYMBOL(inc_node_state); |
734 | |
735 | void mod_node_page_state(struct pglist_data *pgdat, enum node_stat_item item, |
736 | long delta) |
737 | { |
738 | unsigned long flags; |
739 | |
740 | local_irq_save(flags); |
741 | __mod_node_page_state(pgdat, item, delta); |
742 | local_irq_restore(flags); |
743 | } |
744 | EXPORT_SYMBOL(mod_node_page_state); |
745 | |
746 | void inc_node_page_state(struct page *page, enum node_stat_item item) |
747 | { |
748 | unsigned long flags; |
749 | struct pglist_data *pgdat; |
750 | |
751 | pgdat = page_pgdat(page); |
752 | local_irq_save(flags); |
753 | __inc_node_state(pgdat, item); |
754 | local_irq_restore(flags); |
755 | } |
756 | EXPORT_SYMBOL(inc_node_page_state); |
757 | |
758 | void dec_node_page_state(struct page *page, enum node_stat_item item) |
759 | { |
760 | unsigned long flags; |
761 | |
762 | local_irq_save(flags); |
763 | __dec_node_page_state(page, item); |
764 | local_irq_restore(flags); |
765 | } |
766 | EXPORT_SYMBOL(dec_node_page_state); |
767 | #endif |
768 | |
769 | /* |
770 | * Fold a differential into the global counters. |
771 | * Returns the number of counters updated. |
772 | */ |
773 | static int fold_diff(int *zone_diff, int *node_diff) |
774 | { |
775 | int i; |
776 | int changes = 0; |
777 | |
778 | for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) |
779 | if (zone_diff[i]) { |
780 | atomic_long_add(i: zone_diff[i], v: &vm_zone_stat[i]); |
781 | changes++; |
782 | } |
783 | |
784 | for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) |
785 | if (node_diff[i]) { |
786 | atomic_long_add(i: node_diff[i], v: &vm_node_stat[i]); |
787 | changes++; |
788 | } |
789 | return changes; |
790 | } |
791 | |
792 | /* |
793 | * Update the zone counters for the current cpu. |
794 | * |
795 | * Note that refresh_cpu_vm_stats strives to only access |
796 | * node local memory. The per cpu pagesets on remote zones are placed |
797 | * in the memory local to the processor using that pageset. So the |
798 | * loop over all zones will access a series of cachelines local to |
799 | * the processor. |
800 | * |
801 | * The call to zone_page_state_add updates the cachelines with the |
802 | * statistics in the remote zone struct as well as the global cachelines |
803 | * with the global counters. These could cause remote node cache line |
804 | * bouncing and will have to be only done when necessary. |
805 | * |
806 | * The function returns the number of global counters updated. |
807 | */ |
808 | static int refresh_cpu_vm_stats(bool do_pagesets) |
809 | { |
810 | struct pglist_data *pgdat; |
811 | struct zone *zone; |
812 | int i; |
813 | int global_zone_diff[NR_VM_ZONE_STAT_ITEMS] = { 0, }; |
814 | int global_node_diff[NR_VM_NODE_STAT_ITEMS] = { 0, }; |
815 | int changes = 0; |
816 | |
817 | for_each_populated_zone(zone) { |
818 | struct per_cpu_zonestat __percpu *pzstats = zone->per_cpu_zonestats; |
819 | struct per_cpu_pages __percpu *pcp = zone->per_cpu_pageset; |
820 | |
821 | for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) { |
822 | int v; |
823 | |
824 | v = this_cpu_xchg(pzstats->vm_stat_diff[i], 0); |
825 | if (v) { |
826 | |
827 | atomic_long_add(i: v, v: &zone->vm_stat[i]); |
828 | global_zone_diff[i] += v; |
829 | #ifdef CONFIG_NUMA |
830 | /* 3 seconds idle till flush */ |
831 | __this_cpu_write(pcp->expire, 3); |
832 | #endif |
833 | } |
834 | } |
835 | |
836 | if (do_pagesets) { |
837 | cond_resched(); |
838 | |
839 | changes += decay_pcp_high(zone, this_cpu_ptr(pcp)); |
840 | #ifdef CONFIG_NUMA |
841 | /* |
842 | * Deal with draining the remote pageset of this |
843 | * processor |
844 | * |
845 | * Check if there are pages remaining in this pageset |
846 | * if not then there is nothing to expire. |
847 | */ |
848 | if (!__this_cpu_read(pcp->expire) || |
849 | !__this_cpu_read(pcp->count)) |
850 | continue; |
851 | |
852 | /* |
853 | * We never drain zones local to this processor. |
854 | */ |
855 | if (zone_to_nid(zone) == numa_node_id()) { |
856 | __this_cpu_write(pcp->expire, 0); |
857 | continue; |
858 | } |
859 | |
860 | if (__this_cpu_dec_return(pcp->expire)) { |
861 | changes++; |
862 | continue; |
863 | } |
864 | |
865 | if (__this_cpu_read(pcp->count)) { |
866 | drain_zone_pages(zone, this_cpu_ptr(pcp)); |
867 | changes++; |
868 | } |
869 | #endif |
870 | } |
871 | } |
872 | |
873 | for_each_online_pgdat(pgdat) { |
874 | struct per_cpu_nodestat __percpu *p = pgdat->per_cpu_nodestats; |
875 | |
876 | for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) { |
877 | int v; |
878 | |
879 | v = this_cpu_xchg(p->vm_node_stat_diff[i], 0); |
880 | if (v) { |
881 | atomic_long_add(i: v, v: &pgdat->vm_stat[i]); |
882 | global_node_diff[i] += v; |
883 | } |
884 | } |
885 | } |
886 | |
887 | changes += fold_diff(zone_diff: global_zone_diff, node_diff: global_node_diff); |
888 | return changes; |
889 | } |
890 | |
891 | /* |
892 | * Fold the data for an offline cpu into the global array. |
893 | * There cannot be any access by the offline cpu and therefore |
894 | * synchronization is simplified. |
895 | */ |
896 | void cpu_vm_stats_fold(int cpu) |
897 | { |
898 | struct pglist_data *pgdat; |
899 | struct zone *zone; |
900 | int i; |
901 | int global_zone_diff[NR_VM_ZONE_STAT_ITEMS] = { 0, }; |
902 | int global_node_diff[NR_VM_NODE_STAT_ITEMS] = { 0, }; |
903 | |
904 | for_each_populated_zone(zone) { |
905 | struct per_cpu_zonestat *pzstats; |
906 | |
907 | pzstats = per_cpu_ptr(zone->per_cpu_zonestats, cpu); |
908 | |
909 | for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) { |
910 | if (pzstats->vm_stat_diff[i]) { |
911 | int v; |
912 | |
913 | v = pzstats->vm_stat_diff[i]; |
914 | pzstats->vm_stat_diff[i] = 0; |
915 | atomic_long_add(i: v, v: &zone->vm_stat[i]); |
916 | global_zone_diff[i] += v; |
917 | } |
918 | } |
919 | #ifdef CONFIG_NUMA |
920 | for (i = 0; i < NR_VM_NUMA_EVENT_ITEMS; i++) { |
921 | if (pzstats->vm_numa_event[i]) { |
922 | unsigned long v; |
923 | |
924 | v = pzstats->vm_numa_event[i]; |
925 | pzstats->vm_numa_event[i] = 0; |
926 | zone_numa_event_add(x: v, zone, item: i); |
927 | } |
928 | } |
929 | #endif |
930 | } |
931 | |
932 | for_each_online_pgdat(pgdat) { |
933 | struct per_cpu_nodestat *p; |
934 | |
935 | p = per_cpu_ptr(pgdat->per_cpu_nodestats, cpu); |
936 | |
937 | for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) |
938 | if (p->vm_node_stat_diff[i]) { |
939 | int v; |
940 | |
941 | v = p->vm_node_stat_diff[i]; |
942 | p->vm_node_stat_diff[i] = 0; |
943 | atomic_long_add(i: v, v: &pgdat->vm_stat[i]); |
944 | global_node_diff[i] += v; |
945 | } |
946 | } |
947 | |
948 | fold_diff(zone_diff: global_zone_diff, node_diff: global_node_diff); |
949 | } |
950 | |
951 | /* |
952 | * this is only called if !populated_zone(zone), which implies no other users of |
953 | * pset->vm_stat_diff[] exist. |
954 | */ |
955 | void drain_zonestat(struct zone *zone, struct per_cpu_zonestat *pzstats) |
956 | { |
957 | unsigned long v; |
958 | int i; |
959 | |
960 | for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) { |
961 | if (pzstats->vm_stat_diff[i]) { |
962 | v = pzstats->vm_stat_diff[i]; |
963 | pzstats->vm_stat_diff[i] = 0; |
964 | zone_page_state_add(x: v, zone, item: i); |
965 | } |
966 | } |
967 | |
968 | #ifdef CONFIG_NUMA |
969 | for (i = 0; i < NR_VM_NUMA_EVENT_ITEMS; i++) { |
970 | if (pzstats->vm_numa_event[i]) { |
971 | v = pzstats->vm_numa_event[i]; |
972 | pzstats->vm_numa_event[i] = 0; |
973 | zone_numa_event_add(x: v, zone, item: i); |
974 | } |
975 | } |
976 | #endif |
977 | } |
978 | #endif |
979 | |
980 | #ifdef CONFIG_NUMA |
981 | /* |
982 | * Determine the per node value of a stat item. This function |
983 | * is called frequently in a NUMA machine, so try to be as |
984 | * frugal as possible. |
985 | */ |
986 | unsigned long sum_zone_node_page_state(int node, |
987 | enum zone_stat_item item) |
988 | { |
989 | struct zone *zones = NODE_DATA(node)->node_zones; |
990 | int i; |
991 | unsigned long count = 0; |
992 | |
993 | for (i = 0; i < MAX_NR_ZONES; i++) |
994 | count += zone_page_state(zone: zones + i, item); |
995 | |
996 | return count; |
997 | } |
998 | |
999 | /* Determine the per node value of a numa stat item. */ |
1000 | unsigned long sum_zone_numa_event_state(int node, |
1001 | enum numa_stat_item item) |
1002 | { |
1003 | struct zone *zones = NODE_DATA(node)->node_zones; |
1004 | unsigned long count = 0; |
1005 | int i; |
1006 | |
1007 | for (i = 0; i < MAX_NR_ZONES; i++) |
1008 | count += zone_numa_event_state(zone: zones + i, item); |
1009 | |
1010 | return count; |
1011 | } |
1012 | |
1013 | /* |
1014 | * Determine the per node value of a stat item. |
1015 | */ |
1016 | unsigned long node_page_state_pages(struct pglist_data *pgdat, |
1017 | enum node_stat_item item) |
1018 | { |
1019 | long x = atomic_long_read(v: &pgdat->vm_stat[item]); |
1020 | #ifdef CONFIG_SMP |
1021 | if (x < 0) |
1022 | x = 0; |
1023 | #endif |
1024 | return x; |
1025 | } |
1026 | |
1027 | unsigned long node_page_state(struct pglist_data *pgdat, |
1028 | enum node_stat_item item) |
1029 | { |
1030 | VM_WARN_ON_ONCE(vmstat_item_in_bytes(item)); |
1031 | |
1032 | return node_page_state_pages(pgdat, item); |
1033 | } |
1034 | #endif |
1035 | |
1036 | #ifdef CONFIG_COMPACTION |
1037 | |
1038 | struct contig_page_info { |
1039 | unsigned long free_pages; |
1040 | unsigned long free_blocks_total; |
1041 | unsigned long free_blocks_suitable; |
1042 | }; |
1043 | |
1044 | /* |
1045 | * Calculate the number of free pages in a zone, how many contiguous |
1046 | * pages are free and how many are large enough to satisfy an allocation of |
1047 | * the target size. Note that this function makes no attempt to estimate |
1048 | * how many suitable free blocks there *might* be if MOVABLE pages were |
1049 | * migrated. Calculating that is possible, but expensive and can be |
1050 | * figured out from userspace |
1051 | */ |
1052 | static void fill_contig_page_info(struct zone *zone, |
1053 | unsigned int suitable_order, |
1054 | struct contig_page_info *info) |
1055 | { |
1056 | unsigned int order; |
1057 | |
1058 | info->free_pages = 0; |
1059 | info->free_blocks_total = 0; |
1060 | info->free_blocks_suitable = 0; |
1061 | |
1062 | for (order = 0; order <= MAX_ORDER; order++) { |
1063 | unsigned long blocks; |
1064 | |
1065 | /* |
1066 | * Count number of free blocks. |
1067 | * |
1068 | * Access to nr_free is lockless as nr_free is used only for |
1069 | * diagnostic purposes. Use data_race to avoid KCSAN warning. |
1070 | */ |
1071 | blocks = data_race(zone->free_area[order].nr_free); |
1072 | info->free_blocks_total += blocks; |
1073 | |
1074 | /* Count free base pages */ |
1075 | info->free_pages += blocks << order; |
1076 | |
1077 | /* Count the suitable free blocks */ |
1078 | if (order >= suitable_order) |
1079 | info->free_blocks_suitable += blocks << |
1080 | (order - suitable_order); |
1081 | } |
1082 | } |
1083 | |
1084 | /* |
1085 | * A fragmentation index only makes sense if an allocation of a requested |
1086 | * size would fail. If that is true, the fragmentation index indicates |
1087 | * whether external fragmentation or a lack of memory was the problem. |
1088 | * The value can be used to determine if page reclaim or compaction |
1089 | * should be used |
1090 | */ |
1091 | static int __fragmentation_index(unsigned int order, struct contig_page_info *info) |
1092 | { |
1093 | unsigned long requested = 1UL << order; |
1094 | |
1095 | if (WARN_ON_ONCE(order > MAX_ORDER)) |
1096 | return 0; |
1097 | |
1098 | if (!info->free_blocks_total) |
1099 | return 0; |
1100 | |
1101 | /* Fragmentation index only makes sense when a request would fail */ |
1102 | if (info->free_blocks_suitable) |
1103 | return -1000; |
1104 | |
1105 | /* |
1106 | * Index is between 0 and 1 so return within 3 decimal places |
1107 | * |
1108 | * 0 => allocation would fail due to lack of memory |
1109 | * 1 => allocation would fail due to fragmentation |
1110 | */ |
1111 | return 1000 - div_u64( dividend: (1000+(div_u64(dividend: info->free_pages * 1000ULL, divisor: requested))), divisor: info->free_blocks_total); |
1112 | } |
1113 | |
1114 | /* |
1115 | * Calculates external fragmentation within a zone wrt the given order. |
1116 | * It is defined as the percentage of pages found in blocks of size |
1117 | * less than 1 << order. It returns values in range [0, 100]. |
1118 | */ |
1119 | unsigned int extfrag_for_order(struct zone *zone, unsigned int order) |
1120 | { |
1121 | struct contig_page_info info; |
1122 | |
1123 | fill_contig_page_info(zone, suitable_order: order, info: &info); |
1124 | if (info.free_pages == 0) |
1125 | return 0; |
1126 | |
1127 | return div_u64(dividend: (info.free_pages - |
1128 | (info.free_blocks_suitable << order)) * 100, |
1129 | divisor: info.free_pages); |
1130 | } |
1131 | |
1132 | /* Same as __fragmentation index but allocs contig_page_info on stack */ |
1133 | int fragmentation_index(struct zone *zone, unsigned int order) |
1134 | { |
1135 | struct contig_page_info info; |
1136 | |
1137 | fill_contig_page_info(zone, suitable_order: order, info: &info); |
1138 | return __fragmentation_index(order, info: &info); |
1139 | } |
1140 | #endif |
1141 | |
1142 | #if defined(CONFIG_PROC_FS) || defined(CONFIG_SYSFS) || \ |
1143 | defined(CONFIG_NUMA) || defined(CONFIG_MEMCG) |
1144 | #ifdef CONFIG_ZONE_DMA |
1145 | #define TEXT_FOR_DMA(xx) xx "_dma", |
1146 | #else |
1147 | #define TEXT_FOR_DMA(xx) |
1148 | #endif |
1149 | |
1150 | #ifdef CONFIG_ZONE_DMA32 |
1151 | #define TEXT_FOR_DMA32(xx) xx "_dma32", |
1152 | #else |
1153 | #define TEXT_FOR_DMA32(xx) |
1154 | #endif |
1155 | |
1156 | #ifdef CONFIG_HIGHMEM |
1157 | #define TEXT_FOR_HIGHMEM(xx) xx "_high", |
1158 | #else |
1159 | #define TEXT_FOR_HIGHMEM(xx) |
1160 | #endif |
1161 | |
1162 | #ifdef CONFIG_ZONE_DEVICE |
1163 | #define TEXT_FOR_DEVICE(xx) xx "_device", |
1164 | #else |
1165 | #define TEXT_FOR_DEVICE(xx) |
1166 | #endif |
1167 | |
1168 | #define TEXTS_FOR_ZONES(xx) TEXT_FOR_DMA(xx) TEXT_FOR_DMA32(xx) xx "_normal", \ |
1169 | TEXT_FOR_HIGHMEM(xx) xx "_movable", \ |
1170 | TEXT_FOR_DEVICE(xx) |
1171 | |
1172 | const char * const vmstat_text[] = { |
1173 | /* enum zone_stat_item counters */ |
1174 | "nr_free_pages" , |
1175 | "nr_zone_inactive_anon" , |
1176 | "nr_zone_active_anon" , |
1177 | "nr_zone_inactive_file" , |
1178 | "nr_zone_active_file" , |
1179 | "nr_zone_unevictable" , |
1180 | "nr_zone_write_pending" , |
1181 | "nr_mlock" , |
1182 | "nr_bounce" , |
1183 | #if IS_ENABLED(CONFIG_ZSMALLOC) |
1184 | "nr_zspages" , |
1185 | #endif |
1186 | "nr_free_cma" , |
1187 | #ifdef CONFIG_UNACCEPTED_MEMORY |
1188 | "nr_unaccepted" , |
1189 | #endif |
1190 | |
1191 | /* enum numa_stat_item counters */ |
1192 | #ifdef CONFIG_NUMA |
1193 | "numa_hit" , |
1194 | "numa_miss" , |
1195 | "numa_foreign" , |
1196 | "numa_interleave" , |
1197 | "numa_local" , |
1198 | "numa_other" , |
1199 | #endif |
1200 | |
1201 | /* enum node_stat_item counters */ |
1202 | "nr_inactive_anon" , |
1203 | "nr_active_anon" , |
1204 | "nr_inactive_file" , |
1205 | "nr_active_file" , |
1206 | "nr_unevictable" , |
1207 | "nr_slab_reclaimable" , |
1208 | "nr_slab_unreclaimable" , |
1209 | "nr_isolated_anon" , |
1210 | "nr_isolated_file" , |
1211 | "workingset_nodes" , |
1212 | "workingset_refault_anon" , |
1213 | "workingset_refault_file" , |
1214 | "workingset_activate_anon" , |
1215 | "workingset_activate_file" , |
1216 | "workingset_restore_anon" , |
1217 | "workingset_restore_file" , |
1218 | "workingset_nodereclaim" , |
1219 | "nr_anon_pages" , |
1220 | "nr_mapped" , |
1221 | "nr_file_pages" , |
1222 | "nr_dirty" , |
1223 | "nr_writeback" , |
1224 | "nr_writeback_temp" , |
1225 | "nr_shmem" , |
1226 | "nr_shmem_hugepages" , |
1227 | "nr_shmem_pmdmapped" , |
1228 | "nr_file_hugepages" , |
1229 | "nr_file_pmdmapped" , |
1230 | "nr_anon_transparent_hugepages" , |
1231 | "nr_vmscan_write" , |
1232 | "nr_vmscan_immediate_reclaim" , |
1233 | "nr_dirtied" , |
1234 | "nr_written" , |
1235 | "nr_throttled_written" , |
1236 | "nr_kernel_misc_reclaimable" , |
1237 | "nr_foll_pin_acquired" , |
1238 | "nr_foll_pin_released" , |
1239 | "nr_kernel_stack" , |
1240 | #if IS_ENABLED(CONFIG_SHADOW_CALL_STACK) |
1241 | "nr_shadow_call_stack" , |
1242 | #endif |
1243 | "nr_page_table_pages" , |
1244 | "nr_sec_page_table_pages" , |
1245 | #ifdef CONFIG_SWAP |
1246 | "nr_swapcached" , |
1247 | #endif |
1248 | #ifdef CONFIG_NUMA_BALANCING |
1249 | "pgpromote_success" , |
1250 | "pgpromote_candidate" , |
1251 | #endif |
1252 | |
1253 | /* enum writeback_stat_item counters */ |
1254 | "nr_dirty_threshold" , |
1255 | "nr_dirty_background_threshold" , |
1256 | |
1257 | #if defined(CONFIG_VM_EVENT_COUNTERS) || defined(CONFIG_MEMCG) |
1258 | /* enum vm_event_item counters */ |
1259 | "pgpgin" , |
1260 | "pgpgout" , |
1261 | "pswpin" , |
1262 | "pswpout" , |
1263 | |
1264 | TEXTS_FOR_ZONES("pgalloc" ) |
1265 | TEXTS_FOR_ZONES("allocstall" ) |
1266 | TEXTS_FOR_ZONES("pgskip" ) |
1267 | |
1268 | "pgfree" , |
1269 | "pgactivate" , |
1270 | "pgdeactivate" , |
1271 | "pglazyfree" , |
1272 | |
1273 | "pgfault" , |
1274 | "pgmajfault" , |
1275 | "pglazyfreed" , |
1276 | |
1277 | "pgrefill" , |
1278 | "pgreuse" , |
1279 | "pgsteal_kswapd" , |
1280 | "pgsteal_direct" , |
1281 | "pgsteal_khugepaged" , |
1282 | "pgdemote_kswapd" , |
1283 | "pgdemote_direct" , |
1284 | "pgdemote_khugepaged" , |
1285 | "pgscan_kswapd" , |
1286 | "pgscan_direct" , |
1287 | "pgscan_khugepaged" , |
1288 | "pgscan_direct_throttle" , |
1289 | "pgscan_anon" , |
1290 | "pgscan_file" , |
1291 | "pgsteal_anon" , |
1292 | "pgsteal_file" , |
1293 | |
1294 | #ifdef CONFIG_NUMA |
1295 | "zone_reclaim_failed" , |
1296 | #endif |
1297 | "pginodesteal" , |
1298 | "slabs_scanned" , |
1299 | "kswapd_inodesteal" , |
1300 | "kswapd_low_wmark_hit_quickly" , |
1301 | "kswapd_high_wmark_hit_quickly" , |
1302 | "pageoutrun" , |
1303 | |
1304 | "pgrotated" , |
1305 | |
1306 | "drop_pagecache" , |
1307 | "drop_slab" , |
1308 | "oom_kill" , |
1309 | |
1310 | #ifdef CONFIG_NUMA_BALANCING |
1311 | "numa_pte_updates" , |
1312 | "numa_huge_pte_updates" , |
1313 | "numa_hint_faults" , |
1314 | "numa_hint_faults_local" , |
1315 | "numa_pages_migrated" , |
1316 | #endif |
1317 | #ifdef CONFIG_MIGRATION |
1318 | "pgmigrate_success" , |
1319 | "pgmigrate_fail" , |
1320 | "thp_migration_success" , |
1321 | "thp_migration_fail" , |
1322 | "thp_migration_split" , |
1323 | #endif |
1324 | #ifdef CONFIG_COMPACTION |
1325 | "compact_migrate_scanned" , |
1326 | "compact_free_scanned" , |
1327 | "compact_isolated" , |
1328 | "compact_stall" , |
1329 | "compact_fail" , |
1330 | "compact_success" , |
1331 | "compact_daemon_wake" , |
1332 | "compact_daemon_migrate_scanned" , |
1333 | "compact_daemon_free_scanned" , |
1334 | #endif |
1335 | |
1336 | #ifdef CONFIG_HUGETLB_PAGE |
1337 | "htlb_buddy_alloc_success" , |
1338 | "htlb_buddy_alloc_fail" , |
1339 | #endif |
1340 | #ifdef CONFIG_CMA |
1341 | "cma_alloc_success" , |
1342 | "cma_alloc_fail" , |
1343 | #endif |
1344 | "unevictable_pgs_culled" , |
1345 | "unevictable_pgs_scanned" , |
1346 | "unevictable_pgs_rescued" , |
1347 | "unevictable_pgs_mlocked" , |
1348 | "unevictable_pgs_munlocked" , |
1349 | "unevictable_pgs_cleared" , |
1350 | "unevictable_pgs_stranded" , |
1351 | |
1352 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
1353 | "thp_fault_alloc" , |
1354 | "thp_fault_fallback" , |
1355 | "thp_fault_fallback_charge" , |
1356 | "thp_collapse_alloc" , |
1357 | "thp_collapse_alloc_failed" , |
1358 | "thp_file_alloc" , |
1359 | "thp_file_fallback" , |
1360 | "thp_file_fallback_charge" , |
1361 | "thp_file_mapped" , |
1362 | "thp_split_page" , |
1363 | "thp_split_page_failed" , |
1364 | "thp_deferred_split_page" , |
1365 | "thp_split_pmd" , |
1366 | "thp_scan_exceed_none_pte" , |
1367 | "thp_scan_exceed_swap_pte" , |
1368 | "thp_scan_exceed_share_pte" , |
1369 | #ifdef CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD |
1370 | "thp_split_pud" , |
1371 | #endif |
1372 | "thp_zero_page_alloc" , |
1373 | "thp_zero_page_alloc_failed" , |
1374 | "thp_swpout" , |
1375 | "thp_swpout_fallback" , |
1376 | #endif |
1377 | #ifdef CONFIG_MEMORY_BALLOON |
1378 | "balloon_inflate" , |
1379 | "balloon_deflate" , |
1380 | #ifdef CONFIG_BALLOON_COMPACTION |
1381 | "balloon_migrate" , |
1382 | #endif |
1383 | #endif /* CONFIG_MEMORY_BALLOON */ |
1384 | #ifdef CONFIG_DEBUG_TLBFLUSH |
1385 | "nr_tlb_remote_flush" , |
1386 | "nr_tlb_remote_flush_received" , |
1387 | "nr_tlb_local_flush_all" , |
1388 | "nr_tlb_local_flush_one" , |
1389 | #endif /* CONFIG_DEBUG_TLBFLUSH */ |
1390 | |
1391 | #ifdef CONFIG_SWAP |
1392 | "swap_ra" , |
1393 | "swap_ra_hit" , |
1394 | #ifdef CONFIG_KSM |
1395 | "ksm_swpin_copy" , |
1396 | #endif |
1397 | #endif |
1398 | #ifdef CONFIG_KSM |
1399 | "cow_ksm" , |
1400 | #endif |
1401 | #ifdef CONFIG_ZSWAP |
1402 | "zswpin" , |
1403 | "zswpout" , |
1404 | #endif |
1405 | #ifdef CONFIG_X86 |
1406 | "direct_map_level2_splits" , |
1407 | "direct_map_level3_splits" , |
1408 | #endif |
1409 | #ifdef CONFIG_PER_VMA_LOCK_STATS |
1410 | "vma_lock_success" , |
1411 | "vma_lock_abort" , |
1412 | "vma_lock_retry" , |
1413 | "vma_lock_miss" , |
1414 | #endif |
1415 | #endif /* CONFIG_VM_EVENT_COUNTERS || CONFIG_MEMCG */ |
1416 | }; |
1417 | #endif /* CONFIG_PROC_FS || CONFIG_SYSFS || CONFIG_NUMA || CONFIG_MEMCG */ |
1418 | |
1419 | #if (defined(CONFIG_DEBUG_FS) && defined(CONFIG_COMPACTION)) || \ |
1420 | defined(CONFIG_PROC_FS) |
1421 | static void *frag_start(struct seq_file *m, loff_t *pos) |
1422 | { |
1423 | pg_data_t *pgdat; |
1424 | loff_t node = *pos; |
1425 | |
1426 | for (pgdat = first_online_pgdat(); |
1427 | pgdat && node; |
1428 | pgdat = next_online_pgdat(pgdat)) |
1429 | --node; |
1430 | |
1431 | return pgdat; |
1432 | } |
1433 | |
1434 | static void *frag_next(struct seq_file *m, void *arg, loff_t *pos) |
1435 | { |
1436 | pg_data_t *pgdat = (pg_data_t *)arg; |
1437 | |
1438 | (*pos)++; |
1439 | return next_online_pgdat(pgdat); |
1440 | } |
1441 | |
1442 | static void frag_stop(struct seq_file *m, void *arg) |
1443 | { |
1444 | } |
1445 | |
1446 | /* |
1447 | * Walk zones in a node and print using a callback. |
1448 | * If @assert_populated is true, only use callback for zones that are populated. |
1449 | */ |
1450 | static void walk_zones_in_node(struct seq_file *m, pg_data_t *pgdat, |
1451 | bool assert_populated, bool nolock, |
1452 | void (*print)(struct seq_file *m, pg_data_t *, struct zone *)) |
1453 | { |
1454 | struct zone *zone; |
1455 | struct zone *node_zones = pgdat->node_zones; |
1456 | unsigned long flags; |
1457 | |
1458 | for (zone = node_zones; zone - node_zones < MAX_NR_ZONES; ++zone) { |
1459 | if (assert_populated && !populated_zone(zone)) |
1460 | continue; |
1461 | |
1462 | if (!nolock) |
1463 | spin_lock_irqsave(&zone->lock, flags); |
1464 | print(m, pgdat, zone); |
1465 | if (!nolock) |
1466 | spin_unlock_irqrestore(lock: &zone->lock, flags); |
1467 | } |
1468 | } |
1469 | #endif |
1470 | |
1471 | #ifdef CONFIG_PROC_FS |
1472 | static void frag_show_print(struct seq_file *m, pg_data_t *pgdat, |
1473 | struct zone *zone) |
1474 | { |
1475 | int order; |
1476 | |
1477 | seq_printf(m, fmt: "Node %d, zone %8s " , pgdat->node_id, zone->name); |
1478 | for (order = 0; order <= MAX_ORDER; ++order) |
1479 | /* |
1480 | * Access to nr_free is lockless as nr_free is used only for |
1481 | * printing purposes. Use data_race to avoid KCSAN warning. |
1482 | */ |
1483 | seq_printf(m, fmt: "%6lu " , data_race(zone->free_area[order].nr_free)); |
1484 | seq_putc(m, c: '\n'); |
1485 | } |
1486 | |
1487 | /* |
1488 | * This walks the free areas for each zone. |
1489 | */ |
1490 | static int frag_show(struct seq_file *m, void *arg) |
1491 | { |
1492 | pg_data_t *pgdat = (pg_data_t *)arg; |
1493 | walk_zones_in_node(m, pgdat, assert_populated: true, nolock: false, print: frag_show_print); |
1494 | return 0; |
1495 | } |
1496 | |
1497 | static void pagetypeinfo_showfree_print(struct seq_file *m, |
1498 | pg_data_t *pgdat, struct zone *zone) |
1499 | { |
1500 | int order, mtype; |
1501 | |
1502 | for (mtype = 0; mtype < MIGRATE_TYPES; mtype++) { |
1503 | seq_printf(m, fmt: "Node %4d, zone %8s, type %12s " , |
1504 | pgdat->node_id, |
1505 | zone->name, |
1506 | migratetype_names[mtype]); |
1507 | for (order = 0; order <= MAX_ORDER; ++order) { |
1508 | unsigned long freecount = 0; |
1509 | struct free_area *area; |
1510 | struct list_head *curr; |
1511 | bool overflow = false; |
1512 | |
1513 | area = &(zone->free_area[order]); |
1514 | |
1515 | list_for_each(curr, &area->free_list[mtype]) { |
1516 | /* |
1517 | * Cap the free_list iteration because it might |
1518 | * be really large and we are under a spinlock |
1519 | * so a long time spent here could trigger a |
1520 | * hard lockup detector. Anyway this is a |
1521 | * debugging tool so knowing there is a handful |
1522 | * of pages of this order should be more than |
1523 | * sufficient. |
1524 | */ |
1525 | if (++freecount >= 100000) { |
1526 | overflow = true; |
1527 | break; |
1528 | } |
1529 | } |
1530 | seq_printf(m, fmt: "%s%6lu " , overflow ? ">" : "" , freecount); |
1531 | spin_unlock_irq(lock: &zone->lock); |
1532 | cond_resched(); |
1533 | spin_lock_irq(lock: &zone->lock); |
1534 | } |
1535 | seq_putc(m, c: '\n'); |
1536 | } |
1537 | } |
1538 | |
1539 | /* Print out the free pages at each order for each migatetype */ |
1540 | static void pagetypeinfo_showfree(struct seq_file *m, void *arg) |
1541 | { |
1542 | int order; |
1543 | pg_data_t *pgdat = (pg_data_t *)arg; |
1544 | |
1545 | /* Print header */ |
1546 | seq_printf(m, fmt: "%-43s " , "Free pages count per migrate type at order" ); |
1547 | for (order = 0; order <= MAX_ORDER; ++order) |
1548 | seq_printf(m, fmt: "%6d " , order); |
1549 | seq_putc(m, c: '\n'); |
1550 | |
1551 | walk_zones_in_node(m, pgdat, assert_populated: true, nolock: false, print: pagetypeinfo_showfree_print); |
1552 | } |
1553 | |
1554 | static void pagetypeinfo_showblockcount_print(struct seq_file *m, |
1555 | pg_data_t *pgdat, struct zone *zone) |
1556 | { |
1557 | int mtype; |
1558 | unsigned long pfn; |
1559 | unsigned long start_pfn = zone->zone_start_pfn; |
1560 | unsigned long end_pfn = zone_end_pfn(zone); |
1561 | unsigned long count[MIGRATE_TYPES] = { 0, }; |
1562 | |
1563 | for (pfn = start_pfn; pfn < end_pfn; pfn += pageblock_nr_pages) { |
1564 | struct page *page; |
1565 | |
1566 | page = pfn_to_online_page(pfn); |
1567 | if (!page) |
1568 | continue; |
1569 | |
1570 | if (page_zone(page) != zone) |
1571 | continue; |
1572 | |
1573 | mtype = get_pageblock_migratetype(page); |
1574 | |
1575 | if (mtype < MIGRATE_TYPES) |
1576 | count[mtype]++; |
1577 | } |
1578 | |
1579 | /* Print counts */ |
1580 | seq_printf(m, fmt: "Node %d, zone %8s " , pgdat->node_id, zone->name); |
1581 | for (mtype = 0; mtype < MIGRATE_TYPES; mtype++) |
1582 | seq_printf(m, fmt: "%12lu " , count[mtype]); |
1583 | seq_putc(m, c: '\n'); |
1584 | } |
1585 | |
1586 | /* Print out the number of pageblocks for each migratetype */ |
1587 | static void pagetypeinfo_showblockcount(struct seq_file *m, void *arg) |
1588 | { |
1589 | int mtype; |
1590 | pg_data_t *pgdat = (pg_data_t *)arg; |
1591 | |
1592 | seq_printf(m, fmt: "\n%-23s" , "Number of blocks type " ); |
1593 | for (mtype = 0; mtype < MIGRATE_TYPES; mtype++) |
1594 | seq_printf(m, fmt: "%12s " , migratetype_names[mtype]); |
1595 | seq_putc(m, c: '\n'); |
1596 | walk_zones_in_node(m, pgdat, assert_populated: true, nolock: false, |
1597 | print: pagetypeinfo_showblockcount_print); |
1598 | } |
1599 | |
1600 | /* |
1601 | * Print out the number of pageblocks for each migratetype that contain pages |
1602 | * of other types. This gives an indication of how well fallbacks are being |
1603 | * contained by rmqueue_fallback(). It requires information from PAGE_OWNER |
1604 | * to determine what is going on |
1605 | */ |
1606 | static void pagetypeinfo_showmixedcount(struct seq_file *m, pg_data_t *pgdat) |
1607 | { |
1608 | #ifdef CONFIG_PAGE_OWNER |
1609 | int mtype; |
1610 | |
1611 | if (!static_branch_unlikely(&page_owner_inited)) |
1612 | return; |
1613 | |
1614 | drain_all_pages(NULL); |
1615 | |
1616 | seq_printf(m, fmt: "\n%-23s" , "Number of mixed blocks " ); |
1617 | for (mtype = 0; mtype < MIGRATE_TYPES; mtype++) |
1618 | seq_printf(m, fmt: "%12s " , migratetype_names[mtype]); |
1619 | seq_putc(m, c: '\n'); |
1620 | |
1621 | walk_zones_in_node(m, pgdat, assert_populated: true, nolock: true, |
1622 | print: pagetypeinfo_showmixedcount_print); |
1623 | #endif /* CONFIG_PAGE_OWNER */ |
1624 | } |
1625 | |
1626 | /* |
1627 | * This prints out statistics in relation to grouping pages by mobility. |
1628 | * It is expensive to collect so do not constantly read the file. |
1629 | */ |
1630 | static int pagetypeinfo_show(struct seq_file *m, void *arg) |
1631 | { |
1632 | pg_data_t *pgdat = (pg_data_t *)arg; |
1633 | |
1634 | /* check memoryless node */ |
1635 | if (!node_state(node: pgdat->node_id, state: N_MEMORY)) |
1636 | return 0; |
1637 | |
1638 | seq_printf(m, fmt: "Page block order: %d\n" , pageblock_order); |
1639 | seq_printf(m, fmt: "Pages per block: %lu\n" , pageblock_nr_pages); |
1640 | seq_putc(m, c: '\n'); |
1641 | pagetypeinfo_showfree(m, arg: pgdat); |
1642 | pagetypeinfo_showblockcount(m, arg: pgdat); |
1643 | pagetypeinfo_showmixedcount(m, pgdat); |
1644 | |
1645 | return 0; |
1646 | } |
1647 | |
1648 | static const struct seq_operations fragmentation_op = { |
1649 | .start = frag_start, |
1650 | .next = frag_next, |
1651 | .stop = frag_stop, |
1652 | .show = frag_show, |
1653 | }; |
1654 | |
1655 | static const struct seq_operations pagetypeinfo_op = { |
1656 | .start = frag_start, |
1657 | .next = frag_next, |
1658 | .stop = frag_stop, |
1659 | .show = pagetypeinfo_show, |
1660 | }; |
1661 | |
1662 | static bool is_zone_first_populated(pg_data_t *pgdat, struct zone *zone) |
1663 | { |
1664 | int zid; |
1665 | |
1666 | for (zid = 0; zid < MAX_NR_ZONES; zid++) { |
1667 | struct zone *compare = &pgdat->node_zones[zid]; |
1668 | |
1669 | if (populated_zone(zone: compare)) |
1670 | return zone == compare; |
1671 | } |
1672 | |
1673 | return false; |
1674 | } |
1675 | |
1676 | static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat, |
1677 | struct zone *zone) |
1678 | { |
1679 | int i; |
1680 | seq_printf(m, fmt: "Node %d, zone %8s" , pgdat->node_id, zone->name); |
1681 | if (is_zone_first_populated(pgdat, zone)) { |
1682 | seq_printf(m, fmt: "\n per-node stats" ); |
1683 | for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) { |
1684 | unsigned long pages = node_page_state_pages(pgdat, item: i); |
1685 | |
1686 | if (vmstat_item_print_in_thp(item: i)) |
1687 | pages /= HPAGE_PMD_NR; |
1688 | seq_printf(m, fmt: "\n %-12s %lu" , node_stat_name(item: i), |
1689 | pages); |
1690 | } |
1691 | } |
1692 | seq_printf(m, |
1693 | fmt: "\n pages free %lu" |
1694 | "\n boost %lu" |
1695 | "\n min %lu" |
1696 | "\n low %lu" |
1697 | "\n high %lu" |
1698 | "\n spanned %lu" |
1699 | "\n present %lu" |
1700 | "\n managed %lu" |
1701 | "\n cma %lu" , |
1702 | zone_page_state(zone, item: NR_FREE_PAGES), |
1703 | zone->watermark_boost, |
1704 | min_wmark_pages(zone), |
1705 | low_wmark_pages(zone), |
1706 | high_wmark_pages(zone), |
1707 | zone->spanned_pages, |
1708 | zone->present_pages, |
1709 | zone_managed_pages(zone), |
1710 | zone_cma_pages(zone)); |
1711 | |
1712 | seq_printf(m, |
1713 | fmt: "\n protection: (%ld" , |
1714 | zone->lowmem_reserve[0]); |
1715 | for (i = 1; i < ARRAY_SIZE(zone->lowmem_reserve); i++) |
1716 | seq_printf(m, fmt: ", %ld" , zone->lowmem_reserve[i]); |
1717 | seq_putc(m, c: ')'); |
1718 | |
1719 | /* If unpopulated, no other information is useful */ |
1720 | if (!populated_zone(zone)) { |
1721 | seq_putc(m, c: '\n'); |
1722 | return; |
1723 | } |
1724 | |
1725 | for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) |
1726 | seq_printf(m, fmt: "\n %-12s %lu" , zone_stat_name(item: i), |
1727 | zone_page_state(zone, item: i)); |
1728 | |
1729 | #ifdef CONFIG_NUMA |
1730 | for (i = 0; i < NR_VM_NUMA_EVENT_ITEMS; i++) |
1731 | seq_printf(m, fmt: "\n %-12s %lu" , numa_stat_name(item: i), |
1732 | zone_numa_event_state(zone, item: i)); |
1733 | #endif |
1734 | |
1735 | seq_printf(m, fmt: "\n pagesets" ); |
1736 | for_each_online_cpu(i) { |
1737 | struct per_cpu_pages *pcp; |
1738 | struct per_cpu_zonestat __maybe_unused *pzstats; |
1739 | |
1740 | pcp = per_cpu_ptr(zone->per_cpu_pageset, i); |
1741 | seq_printf(m, |
1742 | fmt: "\n cpu: %i" |
1743 | "\n count: %i" |
1744 | "\n high: %i" |
1745 | "\n batch: %i" , |
1746 | i, |
1747 | pcp->count, |
1748 | pcp->high, |
1749 | pcp->batch); |
1750 | #ifdef CONFIG_SMP |
1751 | pzstats = per_cpu_ptr(zone->per_cpu_zonestats, i); |
1752 | seq_printf(m, fmt: "\n vm stats threshold: %d" , |
1753 | pzstats->stat_threshold); |
1754 | #endif |
1755 | } |
1756 | seq_printf(m, |
1757 | fmt: "\n node_unreclaimable: %u" |
1758 | "\n start_pfn: %lu" , |
1759 | pgdat->kswapd_failures >= MAX_RECLAIM_RETRIES, |
1760 | zone->zone_start_pfn); |
1761 | seq_putc(m, c: '\n'); |
1762 | } |
1763 | |
1764 | /* |
1765 | * Output information about zones in @pgdat. All zones are printed regardless |
1766 | * of whether they are populated or not: lowmem_reserve_ratio operates on the |
1767 | * set of all zones and userspace would not be aware of such zones if they are |
1768 | * suppressed here (zoneinfo displays the effect of lowmem_reserve_ratio). |
1769 | */ |
1770 | static int zoneinfo_show(struct seq_file *m, void *arg) |
1771 | { |
1772 | pg_data_t *pgdat = (pg_data_t *)arg; |
1773 | walk_zones_in_node(m, pgdat, assert_populated: false, nolock: false, print: zoneinfo_show_print); |
1774 | return 0; |
1775 | } |
1776 | |
1777 | static const struct seq_operations zoneinfo_op = { |
1778 | .start = frag_start, /* iterate over all zones. The same as in |
1779 | * fragmentation. */ |
1780 | .next = frag_next, |
1781 | .stop = frag_stop, |
1782 | .show = zoneinfo_show, |
1783 | }; |
1784 | |
1785 | #define NR_VMSTAT_ITEMS (NR_VM_ZONE_STAT_ITEMS + \ |
1786 | NR_VM_NUMA_EVENT_ITEMS + \ |
1787 | NR_VM_NODE_STAT_ITEMS + \ |
1788 | NR_VM_WRITEBACK_STAT_ITEMS + \ |
1789 | (IS_ENABLED(CONFIG_VM_EVENT_COUNTERS) ? \ |
1790 | NR_VM_EVENT_ITEMS : 0)) |
1791 | |
1792 | static void *vmstat_start(struct seq_file *m, loff_t *pos) |
1793 | { |
1794 | unsigned long *v; |
1795 | int i; |
1796 | |
1797 | if (*pos >= NR_VMSTAT_ITEMS) |
1798 | return NULL; |
1799 | |
1800 | BUILD_BUG_ON(ARRAY_SIZE(vmstat_text) < NR_VMSTAT_ITEMS); |
1801 | fold_vm_numa_events(); |
1802 | v = kmalloc_array(NR_VMSTAT_ITEMS, size: sizeof(unsigned long), GFP_KERNEL); |
1803 | m->private = v; |
1804 | if (!v) |
1805 | return ERR_PTR(error: -ENOMEM); |
1806 | for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) |
1807 | v[i] = global_zone_page_state(item: i); |
1808 | v += NR_VM_ZONE_STAT_ITEMS; |
1809 | |
1810 | #ifdef CONFIG_NUMA |
1811 | for (i = 0; i < NR_VM_NUMA_EVENT_ITEMS; i++) |
1812 | v[i] = global_numa_event_state(item: i); |
1813 | v += NR_VM_NUMA_EVENT_ITEMS; |
1814 | #endif |
1815 | |
1816 | for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) { |
1817 | v[i] = global_node_page_state_pages(item: i); |
1818 | if (vmstat_item_print_in_thp(item: i)) |
1819 | v[i] /= HPAGE_PMD_NR; |
1820 | } |
1821 | v += NR_VM_NODE_STAT_ITEMS; |
1822 | |
1823 | global_dirty_limits(pbackground: v + NR_DIRTY_BG_THRESHOLD, |
1824 | pdirty: v + NR_DIRTY_THRESHOLD); |
1825 | v += NR_VM_WRITEBACK_STAT_ITEMS; |
1826 | |
1827 | #ifdef CONFIG_VM_EVENT_COUNTERS |
1828 | all_vm_events(v); |
1829 | v[PGPGIN] /= 2; /* sectors -> kbytes */ |
1830 | v[PGPGOUT] /= 2; |
1831 | #endif |
1832 | return (unsigned long *)m->private + *pos; |
1833 | } |
1834 | |
1835 | static void *vmstat_next(struct seq_file *m, void *arg, loff_t *pos) |
1836 | { |
1837 | (*pos)++; |
1838 | if (*pos >= NR_VMSTAT_ITEMS) |
1839 | return NULL; |
1840 | return (unsigned long *)m->private + *pos; |
1841 | } |
1842 | |
1843 | static int vmstat_show(struct seq_file *m, void *arg) |
1844 | { |
1845 | unsigned long *l = arg; |
1846 | unsigned long off = l - (unsigned long *)m->private; |
1847 | |
1848 | seq_puts(m, s: vmstat_text[off]); |
1849 | seq_put_decimal_ull(m, delimiter: " " , num: *l); |
1850 | seq_putc(m, c: '\n'); |
1851 | |
1852 | if (off == NR_VMSTAT_ITEMS - 1) { |
1853 | /* |
1854 | * We've come to the end - add any deprecated counters to avoid |
1855 | * breaking userspace which might depend on them being present. |
1856 | */ |
1857 | seq_puts(m, s: "nr_unstable 0\n" ); |
1858 | } |
1859 | return 0; |
1860 | } |
1861 | |
1862 | static void vmstat_stop(struct seq_file *m, void *arg) |
1863 | { |
1864 | kfree(objp: m->private); |
1865 | m->private = NULL; |
1866 | } |
1867 | |
1868 | static const struct seq_operations vmstat_op = { |
1869 | .start = vmstat_start, |
1870 | .next = vmstat_next, |
1871 | .stop = vmstat_stop, |
1872 | .show = vmstat_show, |
1873 | }; |
1874 | #endif /* CONFIG_PROC_FS */ |
1875 | |
1876 | #ifdef CONFIG_SMP |
1877 | static DEFINE_PER_CPU(struct delayed_work, vmstat_work); |
1878 | int sysctl_stat_interval __read_mostly = HZ; |
1879 | |
1880 | #ifdef CONFIG_PROC_FS |
1881 | static void refresh_vm_stats(struct work_struct *work) |
1882 | { |
1883 | refresh_cpu_vm_stats(do_pagesets: true); |
1884 | } |
1885 | |
1886 | int vmstat_refresh(struct ctl_table *table, int write, |
1887 | void *buffer, size_t *lenp, loff_t *ppos) |
1888 | { |
1889 | long val; |
1890 | int err; |
1891 | int i; |
1892 | |
1893 | /* |
1894 | * The regular update, every sysctl_stat_interval, may come later |
1895 | * than expected: leaving a significant amount in per_cpu buckets. |
1896 | * This is particularly misleading when checking a quantity of HUGE |
1897 | * pages, immediately after running a test. /proc/sys/vm/stat_refresh, |
1898 | * which can equally be echo'ed to or cat'ted from (by root), |
1899 | * can be used to update the stats just before reading them. |
1900 | * |
1901 | * Oh, and since global_zone_page_state() etc. are so careful to hide |
1902 | * transiently negative values, report an error here if any of |
1903 | * the stats is negative, so we know to go looking for imbalance. |
1904 | */ |
1905 | err = schedule_on_each_cpu(func: refresh_vm_stats); |
1906 | if (err) |
1907 | return err; |
1908 | for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) { |
1909 | /* |
1910 | * Skip checking stats known to go negative occasionally. |
1911 | */ |
1912 | switch (i) { |
1913 | case NR_ZONE_WRITE_PENDING: |
1914 | case NR_FREE_CMA_PAGES: |
1915 | continue; |
1916 | } |
1917 | val = atomic_long_read(v: &vm_zone_stat[i]); |
1918 | if (val < 0) { |
1919 | pr_warn("%s: %s %ld\n" , |
1920 | __func__, zone_stat_name(i), val); |
1921 | } |
1922 | } |
1923 | for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++) { |
1924 | /* |
1925 | * Skip checking stats known to go negative occasionally. |
1926 | */ |
1927 | switch (i) { |
1928 | case NR_WRITEBACK: |
1929 | continue; |
1930 | } |
1931 | val = atomic_long_read(v: &vm_node_stat[i]); |
1932 | if (val < 0) { |
1933 | pr_warn("%s: %s %ld\n" , |
1934 | __func__, node_stat_name(i), val); |
1935 | } |
1936 | } |
1937 | if (write) |
1938 | *ppos += *lenp; |
1939 | else |
1940 | *lenp = 0; |
1941 | return 0; |
1942 | } |
1943 | #endif /* CONFIG_PROC_FS */ |
1944 | |
1945 | static void vmstat_update(struct work_struct *w) |
1946 | { |
1947 | if (refresh_cpu_vm_stats(do_pagesets: true)) { |
1948 | /* |
1949 | * Counters were updated so we expect more updates |
1950 | * to occur in the future. Keep on running the |
1951 | * update worker thread. |
1952 | */ |
1953 | queue_delayed_work_on(smp_processor_id(), wq: mm_percpu_wq, |
1954 | this_cpu_ptr(&vmstat_work), |
1955 | delay: round_jiffies_relative(j: sysctl_stat_interval)); |
1956 | } |
1957 | } |
1958 | |
1959 | /* |
1960 | * Check if the diffs for a certain cpu indicate that |
1961 | * an update is needed. |
1962 | */ |
1963 | static bool need_update(int cpu) |
1964 | { |
1965 | pg_data_t *last_pgdat = NULL; |
1966 | struct zone *zone; |
1967 | |
1968 | for_each_populated_zone(zone) { |
1969 | struct per_cpu_zonestat *pzstats = per_cpu_ptr(zone->per_cpu_zonestats, cpu); |
1970 | struct per_cpu_nodestat *n; |
1971 | |
1972 | /* |
1973 | * The fast way of checking if there are any vmstat diffs. |
1974 | */ |
1975 | if (memchr_inv(p: pzstats->vm_stat_diff, c: 0, size: sizeof(pzstats->vm_stat_diff))) |
1976 | return true; |
1977 | |
1978 | if (last_pgdat == zone->zone_pgdat) |
1979 | continue; |
1980 | last_pgdat = zone->zone_pgdat; |
1981 | n = per_cpu_ptr(zone->zone_pgdat->per_cpu_nodestats, cpu); |
1982 | if (memchr_inv(p: n->vm_node_stat_diff, c: 0, size: sizeof(n->vm_node_stat_diff))) |
1983 | return true; |
1984 | } |
1985 | return false; |
1986 | } |
1987 | |
1988 | /* |
1989 | * Switch off vmstat processing and then fold all the remaining differentials |
1990 | * until the diffs stay at zero. The function is used by NOHZ and can only be |
1991 | * invoked when tick processing is not active. |
1992 | */ |
1993 | void quiet_vmstat(void) |
1994 | { |
1995 | if (system_state != SYSTEM_RUNNING) |
1996 | return; |
1997 | |
1998 | if (!delayed_work_pending(this_cpu_ptr(&vmstat_work))) |
1999 | return; |
2000 | |
2001 | if (!need_update(smp_processor_id())) |
2002 | return; |
2003 | |
2004 | /* |
2005 | * Just refresh counters and do not care about the pending delayed |
2006 | * vmstat_update. It doesn't fire that often to matter and canceling |
2007 | * it would be too expensive from this path. |
2008 | * vmstat_shepherd will take care about that for us. |
2009 | */ |
2010 | refresh_cpu_vm_stats(do_pagesets: false); |
2011 | } |
2012 | |
2013 | /* |
2014 | * Shepherd worker thread that checks the |
2015 | * differentials of processors that have their worker |
2016 | * threads for vm statistics updates disabled because of |
2017 | * inactivity. |
2018 | */ |
2019 | static void vmstat_shepherd(struct work_struct *w); |
2020 | |
2021 | static DECLARE_DEFERRABLE_WORK(shepherd, vmstat_shepherd); |
2022 | |
2023 | static void vmstat_shepherd(struct work_struct *w) |
2024 | { |
2025 | int cpu; |
2026 | |
2027 | cpus_read_lock(); |
2028 | /* Check processors whose vmstat worker threads have been disabled */ |
2029 | for_each_online_cpu(cpu) { |
2030 | struct delayed_work *dw = &per_cpu(vmstat_work, cpu); |
2031 | |
2032 | /* |
2033 | * In kernel users of vmstat counters either require the precise value and |
2034 | * they are using zone_page_state_snapshot interface or they can live with |
2035 | * an imprecision as the regular flushing can happen at arbitrary time and |
2036 | * cumulative error can grow (see calculate_normal_threshold). |
2037 | * |
2038 | * From that POV the regular flushing can be postponed for CPUs that have |
2039 | * been isolated from the kernel interference without critical |
2040 | * infrastructure ever noticing. Skip regular flushing from vmstat_shepherd |
2041 | * for all isolated CPUs to avoid interference with the isolated workload. |
2042 | */ |
2043 | if (cpu_is_isolated(cpu)) |
2044 | continue; |
2045 | |
2046 | if (!delayed_work_pending(dw) && need_update(cpu)) |
2047 | queue_delayed_work_on(cpu, wq: mm_percpu_wq, work: dw, delay: 0); |
2048 | |
2049 | cond_resched(); |
2050 | } |
2051 | cpus_read_unlock(); |
2052 | |
2053 | schedule_delayed_work(dwork: &shepherd, |
2054 | delay: round_jiffies_relative(j: sysctl_stat_interval)); |
2055 | } |
2056 | |
2057 | static void __init start_shepherd_timer(void) |
2058 | { |
2059 | int cpu; |
2060 | |
2061 | for_each_possible_cpu(cpu) |
2062 | INIT_DEFERRABLE_WORK(per_cpu_ptr(&vmstat_work, cpu), |
2063 | vmstat_update); |
2064 | |
2065 | schedule_delayed_work(dwork: &shepherd, |
2066 | delay: round_jiffies_relative(j: sysctl_stat_interval)); |
2067 | } |
2068 | |
2069 | static void __init init_cpu_node_state(void) |
2070 | { |
2071 | int node; |
2072 | |
2073 | for_each_online_node(node) { |
2074 | if (!cpumask_empty(srcp: cpumask_of_node(node))) |
2075 | node_set_state(node, state: N_CPU); |
2076 | } |
2077 | } |
2078 | |
2079 | static int vmstat_cpu_online(unsigned int cpu) |
2080 | { |
2081 | refresh_zone_stat_thresholds(); |
2082 | |
2083 | if (!node_state(cpu_to_node(cpu), state: N_CPU)) { |
2084 | node_set_state(cpu_to_node(cpu), state: N_CPU); |
2085 | } |
2086 | |
2087 | return 0; |
2088 | } |
2089 | |
2090 | static int vmstat_cpu_down_prep(unsigned int cpu) |
2091 | { |
2092 | cancel_delayed_work_sync(dwork: &per_cpu(vmstat_work, cpu)); |
2093 | return 0; |
2094 | } |
2095 | |
2096 | static int vmstat_cpu_dead(unsigned int cpu) |
2097 | { |
2098 | const struct cpumask *node_cpus; |
2099 | int node; |
2100 | |
2101 | node = cpu_to_node(cpu); |
2102 | |
2103 | refresh_zone_stat_thresholds(); |
2104 | node_cpus = cpumask_of_node(node); |
2105 | if (!cpumask_empty(srcp: node_cpus)) |
2106 | return 0; |
2107 | |
2108 | node_clear_state(node, state: N_CPU); |
2109 | |
2110 | return 0; |
2111 | } |
2112 | |
2113 | #endif |
2114 | |
2115 | struct workqueue_struct *mm_percpu_wq; |
2116 | |
2117 | void __init init_mm_internals(void) |
2118 | { |
2119 | int ret __maybe_unused; |
2120 | |
2121 | mm_percpu_wq = alloc_workqueue(fmt: "mm_percpu_wq" , flags: WQ_MEM_RECLAIM, max_active: 0); |
2122 | |
2123 | #ifdef CONFIG_SMP |
2124 | ret = cpuhp_setup_state_nocalls(state: CPUHP_MM_VMSTAT_DEAD, name: "mm/vmstat:dead" , |
2125 | NULL, teardown: vmstat_cpu_dead); |
2126 | if (ret < 0) |
2127 | pr_err("vmstat: failed to register 'dead' hotplug state\n" ); |
2128 | |
2129 | ret = cpuhp_setup_state_nocalls(state: CPUHP_AP_ONLINE_DYN, name: "mm/vmstat:online" , |
2130 | startup: vmstat_cpu_online, |
2131 | teardown: vmstat_cpu_down_prep); |
2132 | if (ret < 0) |
2133 | pr_err("vmstat: failed to register 'online' hotplug state\n" ); |
2134 | |
2135 | cpus_read_lock(); |
2136 | init_cpu_node_state(); |
2137 | cpus_read_unlock(); |
2138 | |
2139 | start_shepherd_timer(); |
2140 | #endif |
2141 | #ifdef CONFIG_PROC_FS |
2142 | proc_create_seq("buddyinfo" , 0444, NULL, &fragmentation_op); |
2143 | proc_create_seq("pagetypeinfo" , 0400, NULL, &pagetypeinfo_op); |
2144 | proc_create_seq("vmstat" , 0444, NULL, &vmstat_op); |
2145 | proc_create_seq("zoneinfo" , 0444, NULL, &zoneinfo_op); |
2146 | #endif |
2147 | } |
2148 | |
2149 | #if defined(CONFIG_DEBUG_FS) && defined(CONFIG_COMPACTION) |
2150 | |
2151 | /* |
2152 | * Return an index indicating how much of the available free memory is |
2153 | * unusable for an allocation of the requested size. |
2154 | */ |
2155 | static int unusable_free_index(unsigned int order, |
2156 | struct contig_page_info *info) |
2157 | { |
2158 | /* No free memory is interpreted as all free memory is unusable */ |
2159 | if (info->free_pages == 0) |
2160 | return 1000; |
2161 | |
2162 | /* |
2163 | * Index should be a value between 0 and 1. Return a value to 3 |
2164 | * decimal places. |
2165 | * |
2166 | * 0 => no fragmentation |
2167 | * 1 => high fragmentation |
2168 | */ |
2169 | return div_u64(dividend: (info->free_pages - (info->free_blocks_suitable << order)) * 1000ULL, divisor: info->free_pages); |
2170 | |
2171 | } |
2172 | |
2173 | static void unusable_show_print(struct seq_file *m, |
2174 | pg_data_t *pgdat, struct zone *zone) |
2175 | { |
2176 | unsigned int order; |
2177 | int index; |
2178 | struct contig_page_info info; |
2179 | |
2180 | seq_printf(m, fmt: "Node %d, zone %8s " , |
2181 | pgdat->node_id, |
2182 | zone->name); |
2183 | for (order = 0; order <= MAX_ORDER; ++order) { |
2184 | fill_contig_page_info(zone, suitable_order: order, info: &info); |
2185 | index = unusable_free_index(order, info: &info); |
2186 | seq_printf(m, fmt: "%d.%03d " , index / 1000, index % 1000); |
2187 | } |
2188 | |
2189 | seq_putc(m, c: '\n'); |
2190 | } |
2191 | |
2192 | /* |
2193 | * Display unusable free space index |
2194 | * |
2195 | * The unusable free space index measures how much of the available free |
2196 | * memory cannot be used to satisfy an allocation of a given size and is a |
2197 | * value between 0 and 1. The higher the value, the more of free memory is |
2198 | * unusable and by implication, the worse the external fragmentation is. This |
2199 | * can be expressed as a percentage by multiplying by 100. |
2200 | */ |
2201 | static int unusable_show(struct seq_file *m, void *arg) |
2202 | { |
2203 | pg_data_t *pgdat = (pg_data_t *)arg; |
2204 | |
2205 | /* check memoryless node */ |
2206 | if (!node_state(node: pgdat->node_id, state: N_MEMORY)) |
2207 | return 0; |
2208 | |
2209 | walk_zones_in_node(m, pgdat, assert_populated: true, nolock: false, print: unusable_show_print); |
2210 | |
2211 | return 0; |
2212 | } |
2213 | |
2214 | static const struct seq_operations unusable_sops = { |
2215 | .start = frag_start, |
2216 | .next = frag_next, |
2217 | .stop = frag_stop, |
2218 | .show = unusable_show, |
2219 | }; |
2220 | |
2221 | DEFINE_SEQ_ATTRIBUTE(unusable); |
2222 | |
2223 | static void extfrag_show_print(struct seq_file *m, |
2224 | pg_data_t *pgdat, struct zone *zone) |
2225 | { |
2226 | unsigned int order; |
2227 | int index; |
2228 | |
2229 | /* Alloc on stack as interrupts are disabled for zone walk */ |
2230 | struct contig_page_info info; |
2231 | |
2232 | seq_printf(m, fmt: "Node %d, zone %8s " , |
2233 | pgdat->node_id, |
2234 | zone->name); |
2235 | for (order = 0; order <= MAX_ORDER; ++order) { |
2236 | fill_contig_page_info(zone, suitable_order: order, info: &info); |
2237 | index = __fragmentation_index(order, info: &info); |
2238 | seq_printf(m, fmt: "%2d.%03d " , index / 1000, index % 1000); |
2239 | } |
2240 | |
2241 | seq_putc(m, c: '\n'); |
2242 | } |
2243 | |
2244 | /* |
2245 | * Display fragmentation index for orders that allocations would fail for |
2246 | */ |
2247 | static int extfrag_show(struct seq_file *m, void *arg) |
2248 | { |
2249 | pg_data_t *pgdat = (pg_data_t *)arg; |
2250 | |
2251 | walk_zones_in_node(m, pgdat, assert_populated: true, nolock: false, print: extfrag_show_print); |
2252 | |
2253 | return 0; |
2254 | } |
2255 | |
2256 | static const struct seq_operations extfrag_sops = { |
2257 | .start = frag_start, |
2258 | .next = frag_next, |
2259 | .stop = frag_stop, |
2260 | .show = extfrag_show, |
2261 | }; |
2262 | |
2263 | DEFINE_SEQ_ATTRIBUTE(extfrag); |
2264 | |
2265 | static int __init extfrag_debug_init(void) |
2266 | { |
2267 | struct dentry *extfrag_debug_root; |
2268 | |
2269 | extfrag_debug_root = debugfs_create_dir(name: "extfrag" , NULL); |
2270 | |
2271 | debugfs_create_file(name: "unusable_index" , mode: 0444, parent: extfrag_debug_root, NULL, |
2272 | fops: &unusable_fops); |
2273 | |
2274 | debugfs_create_file(name: "extfrag_index" , mode: 0444, parent: extfrag_debug_root, NULL, |
2275 | fops: &extfrag_fops); |
2276 | |
2277 | return 0; |
2278 | } |
2279 | |
2280 | module_init(extfrag_debug_init); |
2281 | #endif |
2282 | |