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lockdep: BFS cleanup
[linux-2.6-block.git] / kernel / lockdep_proc.c
CommitLineData
a8f24a39
IM		 1/*
2 * kernel/lockdep_proc.c
3 *
4 * Runtime locking correctness validator
5 *
6 * Started by Ingo Molnar:
7 *
4b32d0a4
PZ		 8 * Copyright (C) 2006,2007 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
9 * Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
a8f24a39
IM		 10 *
11 * Code for /proc/lockdep and /proc/lockdep_stats:
12 *
13 */
a8f24a39
IM		 14#include <linux/module.h>
15#include <linux/proc_fs.h>
16#include <linux/seq_file.h>
17#include <linux/kallsyms.h>
18#include <linux/debug_locks.h>
c46261de
PZ		 19#include <linux/vmalloc.h>
20#include <linux/sort.h>
21#include <asm/uaccess.h>
22#include <asm/div64.h>
a8f24a39
IM		 23
24#include "lockdep_internals.h"
25
26static void *l_next(struct seq_file *m, void *v, loff_t *pos)
27{
94c61c0a 28 struct lock_class *class;
a8f24a39
IM		 29
30 (*pos)++;
31
94c61c0a
TP		 32 if (v == SEQ_START_TOKEN)
33 class = m->private;
34 else {
35 class = v;
36
37 if (class->lock_entry.next != &all_lock_classes)
38 class = list_entry(class->lock_entry.next,
39 struct lock_class, lock_entry);
40 else
41 class = NULL;
42 }
a8f24a39
IM		 43
44 return class;
45}
46
47static void *l_start(struct seq_file *m, loff_t *pos)
48{
94c61c0a
TP		 49 struct lock_class *class;
50 loff_t i = 0;
a8f24a39 51
94c61c0a
TP		 52 if (*pos == 0)
53 return SEQ_START_TOKEN;
a8f24a39 54
94c61c0a
TP		 55 list_for_each_entry(class, &all_lock_classes, lock_entry) {
56 if (++i == *pos)
57 return class;
58 }
59 return NULL;
a8f24a39
IM		 60}
61
62static void l_stop(struct seq_file *m, void *v)
63{
64}
65
068135e6
JB		 66static void print_name(struct seq_file *m, struct lock_class *class)
67{
68 char str[128];
69 const char *name = class->name;
70
71 if (!name) {
72 name = __get_key_name(class->key, str);
73 seq_printf(m, "%s", name);
74 } else{
75 seq_printf(m, "%s", name);
76 if (class->name_version > 1)
77 seq_printf(m, "#%d", class->name_version);
78 if (class->subclass)
79 seq_printf(m, "/%d", class->subclass);
80 }
81}
82
a8f24a39
IM		 83static int l_show(struct seq_file *m, void *v)
84{
94c61c0a 85 struct lock_class *class = v;
068135e6 86 struct lock_list *entry;
f510b233 87 char usage[LOCK_USAGE_CHARS];
a8f24a39 88
94c61c0a
TP		 89 if (v == SEQ_START_TOKEN) {
90 seq_printf(m, "all lock classes:\n");
91 return 0;
92 }
93
a8f24a39
IM		 94 seq_printf(m, "%p", class->key);
95#ifdef CONFIG_DEBUG_LOCKDEP
96 seq_printf(m, " OPS:%8ld", class->ops);
97#endif
df60a844
SH		 98#ifdef CONFIG_PROVE_LOCKING
99 seq_printf(m, " FD:%5ld", lockdep_count_forward_deps(class));
100 seq_printf(m, " BD:%5ld", lockdep_count_backward_deps(class));
101#endif
a8f24a39 102
f510b233
PZ		 103 get_usage_chars(class, usage);
104 seq_printf(m, " %s", usage);
a8f24a39 105
068135e6
JB		 106 seq_printf(m, ": ");
107 print_name(m, class);
108 seq_puts(m, "\n");
109
110 list_for_each_entry(entry, &class->locks_after, entry) {
111 if (entry->distance == 1) {
2429e4ee 112 seq_printf(m, " -> [%p] ", entry->class->key);
068135e6
JB		 113 print_name(m, entry->class);
114 seq_puts(m, "\n");
115 }
a8f24a39
IM		 116 }
117 seq_puts(m, "\n");
118
119 return 0;
120}
121
15ad7cdc 122static const struct seq_operations lockdep_ops = {
a8f24a39
IM		 123 .start = l_start,
124 .next = l_next,
125 .stop = l_stop,
126 .show = l_show,
127};
128
129static int lockdep_open(struct inode *inode, struct file *file)
130{
131 int res = seq_open(file, &lockdep_ops);
132 if (!res) {
133 struct seq_file *m = file->private_data;
134
135 if (!list_empty(&all_lock_classes))
136 m->private = list_entry(all_lock_classes.next,
137 struct lock_class, lock_entry);
138 else
139 m->private = NULL;
140 }
141 return res;
142}
143
15ad7cdc 144static const struct file_operations proc_lockdep_operations = {
a8f24a39
IM		 145 .open = lockdep_open,
146 .read = seq_read,
147 .llseek = seq_lseek,
148 .release = seq_release,
149};
150
cd1a28e8 151#ifdef CONFIG_PROVE_LOCKING
443cd507
HY		 152static void *lc_next(struct seq_file *m, void *v, loff_t *pos)
153{
154 struct lock_chain *chain;
155
156 (*pos)++;
157
158 if (v == SEQ_START_TOKEN)
159 chain = m->private;
160 else {
161 chain = v;
162
163 if (*pos < nr_lock_chains)
164 chain = lock_chains + *pos;
165 else
166 chain = NULL;
167 }
168
169 return chain;
170}
171
172static void *lc_start(struct seq_file *m, loff_t *pos)
173{
174 if (*pos == 0)
175 return SEQ_START_TOKEN;
176
177 if (*pos < nr_lock_chains)
178 return lock_chains + *pos;
179
180 return NULL;
181}
182
183static void lc_stop(struct seq_file *m, void *v)
184{
185}
186
187static int lc_show(struct seq_file *m, void *v)
188{
189 struct lock_chain *chain = v;
190 struct lock_class *class;
191 int i;
192
193 if (v == SEQ_START_TOKEN) {
194 seq_printf(m, "all lock chains:\n");
195 return 0;
196 }
197
198 seq_printf(m, "irq_context: %d\n", chain->irq_context);
199
200 for (i = 0; i < chain->depth; i++) {
201 class = lock_chain_get_class(chain, i);
8bfe0298
RV		 202 if (!class->key)
203 continue;
204
443cd507
HY		 205 seq_printf(m, "[%p] ", class->key);
206 print_name(m, class);
207 seq_puts(m, "\n");
208 }
209 seq_puts(m, "\n");
210
211 return 0;
212}
213
214static const struct seq_operations lockdep_chains_ops = {
215 .start = lc_start,
216 .next = lc_next,
217 .stop = lc_stop,
218 .show = lc_show,
219};
220
221static int lockdep_chains_open(struct inode *inode, struct file *file)
222{
223 int res = seq_open(file, &lockdep_chains_ops);
224 if (!res) {
225 struct seq_file *m = file->private_data;
226
227 if (nr_lock_chains)
228 m->private = lock_chains;
229 else
230 m->private = NULL;
231 }
232 return res;
233}
234
235static const struct file_operations proc_lockdep_chains_operations = {
236 .open = lockdep_chains_open,
237 .read = seq_read,
238 .llseek = seq_lseek,
239 .release = seq_release,
240};
cd1a28e8 241#endif /* CONFIG_PROVE_LOCKING */
443cd507 242
a8f24a39
IM		 243static void lockdep_stats_debug_show(struct seq_file *m)
244{
245#ifdef CONFIG_DEBUG_LOCKDEP
246 unsigned int hi1 = debug_atomic_read(&hardirqs_on_events),
247 hi2 = debug_atomic_read(&hardirqs_off_events),
248 hr1 = debug_atomic_read(&redundant_hardirqs_on),
249 hr2 = debug_atomic_read(&redundant_hardirqs_off),
250 si1 = debug_atomic_read(&softirqs_on_events),
251 si2 = debug_atomic_read(&softirqs_off_events),
252 sr1 = debug_atomic_read(&redundant_softirqs_on),
253 sr2 = debug_atomic_read(&redundant_softirqs_off);
254
255 seq_printf(m, " chain lookup misses: %11u\n",
256 debug_atomic_read(&chain_lookup_misses));
257 seq_printf(m, " chain lookup hits: %11u\n",
258 debug_atomic_read(&chain_lookup_hits));
259 seq_printf(m, " cyclic checks: %11u\n",
260 debug_atomic_read(&nr_cyclic_checks));
261 seq_printf(m, " cyclic-check recursions: %11u\n",
262 debug_atomic_read(&nr_cyclic_check_recursions));
263 seq_printf(m, " find-mask forwards checks: %11u\n",
264 debug_atomic_read(&nr_find_usage_forwards_checks));
265 seq_printf(m, " find-mask forwards recursions: %11u\n",
266 debug_atomic_read(&nr_find_usage_forwards_recursions));
267 seq_printf(m, " find-mask backwards checks: %11u\n",
268 debug_atomic_read(&nr_find_usage_backwards_checks));
269 seq_printf(m, " find-mask backwards recursions:%11u\n",
270 debug_atomic_read(&nr_find_usage_backwards_recursions));
271
272 seq_printf(m, " hardirq on events: %11u\n", hi1);
273 seq_printf(m, " hardirq off events: %11u\n", hi2);
274 seq_printf(m, " redundant hardirq ons: %11u\n", hr1);
275 seq_printf(m, " redundant hardirq offs: %11u\n", hr2);
276 seq_printf(m, " softirq on events: %11u\n", si1);
277 seq_printf(m, " softirq off events: %11u\n", si2);
278 seq_printf(m, " redundant softirq ons: %11u\n", sr1);
279 seq_printf(m, " redundant softirq offs: %11u\n", sr2);
280#endif
281}
282
283static int lockdep_stats_show(struct seq_file *m, void *v)
284{
285 struct lock_class *class;
286 unsigned long nr_unused = 0, nr_uncategorized = 0,
287 nr_irq_safe = 0, nr_irq_unsafe = 0,
288 nr_softirq_safe = 0, nr_softirq_unsafe = 0,
289 nr_hardirq_safe = 0, nr_hardirq_unsafe = 0,
290 nr_irq_read_safe = 0, nr_irq_read_unsafe = 0,
291 nr_softirq_read_safe = 0, nr_softirq_read_unsafe = 0,
292 nr_hardirq_read_safe = 0, nr_hardirq_read_unsafe = 0,
293 sum_forward_deps = 0, factor = 0;
294
295 list_for_each_entry(class, &all_lock_classes, lock_entry) {
296
297 if (class->usage_mask == 0)
298 nr_unused++;
299 if (class->usage_mask == LOCKF_USED)
300 nr_uncategorized++;
301 if (class->usage_mask & LOCKF_USED_IN_IRQ)
302 nr_irq_safe++;
4fc95e86 303 if (class->usage_mask & LOCKF_ENABLED_IRQ)
a8f24a39
IM		 304 nr_irq_unsafe++;
305 if (class->usage_mask & LOCKF_USED_IN_SOFTIRQ)
306 nr_softirq_safe++;
4fc95e86 307 if (class->usage_mask & LOCKF_ENABLED_SOFTIRQ)
a8f24a39
IM		 308 nr_softirq_unsafe++;
309 if (class->usage_mask & LOCKF_USED_IN_HARDIRQ)
310 nr_hardirq_safe++;
4fc95e86 311 if (class->usage_mask & LOCKF_ENABLED_HARDIRQ)
a8f24a39
IM		 312 nr_hardirq_unsafe++;
313 if (class->usage_mask & LOCKF_USED_IN_IRQ_READ)
314 nr_irq_read_safe++;
4fc95e86 315 if (class->usage_mask & LOCKF_ENABLED_IRQ_READ)
a8f24a39
IM		 316 nr_irq_read_unsafe++;
317 if (class->usage_mask & LOCKF_USED_IN_SOFTIRQ_READ)
318 nr_softirq_read_safe++;
4fc95e86 319 if (class->usage_mask & LOCKF_ENABLED_SOFTIRQ_READ)
a8f24a39
IM		 320 nr_softirq_read_unsafe++;
321 if (class->usage_mask & LOCKF_USED_IN_HARDIRQ_READ)
322 nr_hardirq_read_safe++;
4fc95e86 323 if (class->usage_mask & LOCKF_ENABLED_HARDIRQ_READ)
a8f24a39
IM		 324 nr_hardirq_read_unsafe++;
325
df60a844 326#ifdef CONFIG_PROVE_LOCKING
419ca3f1 327 sum_forward_deps += lockdep_count_forward_deps(class);
df60a844 328#endif
a8f24a39 329 }
501b9ebf 330#ifdef CONFIG_DEBUG_LOCKDEP
a8f24a39
IM		 331 DEBUG_LOCKS_WARN_ON(debug_atomic_read(&nr_unused_locks) != nr_unused);
332#endif
333 seq_printf(m, " lock-classes: %11lu [max: %lu]\n",
334 nr_lock_classes, MAX_LOCKDEP_KEYS);
335 seq_printf(m, " direct dependencies: %11lu [max: %lu]\n",
336 nr_list_entries, MAX_LOCKDEP_ENTRIES);
337 seq_printf(m, " indirect dependencies: %11lu\n",
338 sum_forward_deps);
339
340 /*
341 * Total number of dependencies:
342 *
343 * All irq-safe locks may nest inside irq-unsafe locks,
344 * plus all the other known dependencies:
345 */
346 seq_printf(m, " all direct dependencies: %11lu\n",
347 nr_irq_unsafe * nr_irq_safe +
348 nr_hardirq_unsafe * nr_hardirq_safe +
349 nr_list_entries);
350
351 /*
352 * Estimated factor between direct and indirect
353 * dependencies:
354 */
355 if (nr_list_entries)
356 factor = sum_forward_deps / nr_list_entries;
357
8e18257d 358#ifdef CONFIG_PROVE_LOCKING
a8f24a39
IM		 359 seq_printf(m, " dependency chains: %11lu [max: %lu]\n",
360 nr_lock_chains, MAX_LOCKDEP_CHAINS);
443cd507 361 seq_printf(m, " dependency chain hlocks: %11d [max: %lu]\n",
cd1a28e8 362 nr_chain_hlocks, MAX_LOCKDEP_CHAIN_HLOCKS);
8e18257d 363#endif
a8f24a39
IM		 364
365#ifdef CONFIG_TRACE_IRQFLAGS
366 seq_printf(m, " in-hardirq chains: %11u\n",
367 nr_hardirq_chains);
368 seq_printf(m, " in-softirq chains: %11u\n",
369 nr_softirq_chains);
370#endif
371 seq_printf(m, " in-process chains: %11u\n",
372 nr_process_chains);
373 seq_printf(m, " stack-trace entries: %11lu [max: %lu]\n",
374 nr_stack_trace_entries, MAX_STACK_TRACE_ENTRIES);
375 seq_printf(m, " combined max dependencies: %11u\n",
376 (nr_hardirq_chains + 1) *
377 (nr_softirq_chains + 1) *
378 (nr_process_chains + 1)
379 );
380 seq_printf(m, " hardirq-safe locks: %11lu\n",
381 nr_hardirq_safe);
382 seq_printf(m, " hardirq-unsafe locks: %11lu\n",
383 nr_hardirq_unsafe);
384 seq_printf(m, " softirq-safe locks: %11lu\n",
385 nr_softirq_safe);
386 seq_printf(m, " softirq-unsafe locks: %11lu\n",
387 nr_softirq_unsafe);
388 seq_printf(m, " irq-safe locks: %11lu\n",
389 nr_irq_safe);
390 seq_printf(m, " irq-unsafe locks: %11lu\n",
391 nr_irq_unsafe);
392
393 seq_printf(m, " hardirq-read-safe locks: %11lu\n",
394 nr_hardirq_read_safe);
395 seq_printf(m, " hardirq-read-unsafe locks: %11lu\n",
396 nr_hardirq_read_unsafe);
397 seq_printf(m, " softirq-read-safe locks: %11lu\n",
398 nr_softirq_read_safe);
399 seq_printf(m, " softirq-read-unsafe locks: %11lu\n",
400 nr_softirq_read_unsafe);
401 seq_printf(m, " irq-read-safe locks: %11lu\n",
402 nr_irq_read_safe);
403 seq_printf(m, " irq-read-unsafe locks: %11lu\n",
404 nr_irq_read_unsafe);
405
406 seq_printf(m, " uncategorized locks: %11lu\n",
407 nr_uncategorized);
408 seq_printf(m, " unused locks: %11lu\n",
409 nr_unused);
410 seq_printf(m, " max locking depth: %11u\n",
411 max_lockdep_depth);
412 seq_printf(m, " max recursion depth: %11u\n",
413 max_recursion_depth);
12f3dfd0
ML		 414 seq_printf(m, " max bfs queue depth: %11u\n",
415 max_bfs_queue_depth);
a8f24a39
IM		 416 lockdep_stats_debug_show(m);
417 seq_printf(m, " debug_locks: %11u\n",
418 debug_locks);
419
420 return 0;
421}
422
423static int lockdep_stats_open(struct inode *inode, struct file *file)
424{
425 return single_open(file, lockdep_stats_show, NULL);
426}
427
15ad7cdc 428static const struct file_operations proc_lockdep_stats_operations = {
a8f24a39
IM		 429 .open = lockdep_stats_open,
430 .read = seq_read,
431 .llseek = seq_lseek,
c0f33586 432 .release = single_release,
a8f24a39
IM		 433};
434
c46261de
PZ		 435#ifdef CONFIG_LOCK_STAT
436
437struct lock_stat_data {
438 struct lock_class *class;
439 struct lock_class_stats stats;
440};
441
442struct lock_stat_seq {
443 struct lock_stat_data *iter;
444 struct lock_stat_data *iter_end;
445 struct lock_stat_data stats[MAX_LOCKDEP_KEYS];
446};
447
448/*
449 * sort on absolute number of contentions
450 */
451static int lock_stat_cmp(const void *l, const void *r)
452{
453 const struct lock_stat_data *dl = l, *dr = r;
454 unsigned long nl, nr;
455
456 nl = dl->stats.read_waittime.nr + dl->stats.write_waittime.nr;
457 nr = dr->stats.read_waittime.nr + dr->stats.write_waittime.nr;
458
459 return nr - nl;
460}
461
462static void seq_line(struct seq_file *m, char c, int offset, int length)
463{
464 int i;
465
466 for (i = 0; i < offset; i++)
467 seq_puts(m, " ");
468 for (i = 0; i < length; i++)
469 seq_printf(m, "%c", c);
470 seq_puts(m, "\n");
471}
472
473static void snprint_time(char *buf, size_t bufsiz, s64 nr)
474{
6918bc5c
PZ		 475 s64 div;
476 s32 rem;
c46261de 477
2189459d 478 nr += 5; /* for display rounding */
6918bc5c
PZ		 479 div = div_s64_rem(nr, 1000, &rem);
480 snprintf(buf, bufsiz, "%lld.%02d", (long long)div, (int)rem/10);
c46261de
PZ		 481}
482
483static void seq_time(struct seq_file *m, s64 time)
484{
485 char num[15];
486
487 snprint_time(num, sizeof(num), time);
488 seq_printf(m, " %14s", num);
489}
490
491static void seq_lock_time(struct seq_file *m, struct lock_time *lt)
492{
493 seq_printf(m, "%14lu", lt->nr);
494 seq_time(m, lt->min);
495 seq_time(m, lt->max);
496 seq_time(m, lt->total);
497}
498
499static void seq_stats(struct seq_file *m, struct lock_stat_data *data)
500{
501 char name[39];
502 struct lock_class *class;
503 struct lock_class_stats *stats;
504 int i, namelen;
505
506 class = data->class;
507 stats = &data->stats;
508
d38e1d5a
PZ		 509 namelen = 38;
510 if (class->name_version > 1)
511 namelen -= 2; /* XXX truncates versions > 9 */
512 if (class->subclass)
513 namelen -= 2;
514
515 if (!class->name) {
516 char str[KSYM_NAME_LEN];
517 const char *key_name;
518
519 key_name = __get_key_name(class->key, str);
520 snprintf(name, namelen, "%s", key_name);
521 } else {
522 snprintf(name, namelen, "%s", class->name);
523 }
c46261de 524 namelen = strlen(name);
d38e1d5a
PZ		 525 if (class->name_version > 1) {
526 snprintf(name+namelen, 3, "#%d", class->name_version);
527 namelen += 2;
528 }
529 if (class->subclass) {
530 snprintf(name+namelen, 3, "/%d", class->subclass);
531 namelen += 2;
532 }
c46261de
PZ		 533
534 if (stats->write_holdtime.nr) {
535 if (stats->read_holdtime.nr)
536 seq_printf(m, "%38s-W:", name);
537 else
538 seq_printf(m, "%40s:", name);
539
96645678 540 seq_printf(m, "%14lu ", stats->bounces[bounce_contended_write]);
c46261de 541 seq_lock_time(m, &stats->write_waittime);
96645678 542 seq_printf(m, " %14lu ", stats->bounces[bounce_acquired_write]);
c46261de
PZ		 543 seq_lock_time(m, &stats->write_holdtime);
544 seq_puts(m, "\n");
545 }
546
547 if (stats->read_holdtime.nr) {
548 seq_printf(m, "%38s-R:", name);
96645678 549 seq_printf(m, "%14lu ", stats->bounces[bounce_contended_read]);
c46261de 550 seq_lock_time(m, &stats->read_waittime);
96645678 551 seq_printf(m, " %14lu ", stats->bounces[bounce_acquired_read]);
c46261de
PZ		 552 seq_lock_time(m, &stats->read_holdtime);
553 seq_puts(m, "\n");
554 }
555
556 if (stats->read_waittime.nr + stats->write_waittime.nr == 0)
557 return;
558
559 if (stats->read_holdtime.nr)
560 namelen += 2;
561
c7e78cff 562 for (i = 0; i < LOCKSTAT_POINTS; i++) {
c46261de
PZ		 563 char sym[KSYM_SYMBOL_LEN];
564 char ip[32];
565
566 if (class->contention_point[i] == 0)
567 break;
568
569 if (!i)
570 seq_line(m, '-', 40-namelen, namelen);
571
572 sprint_symbol(sym, class->contention_point[i]);
573 snprintf(ip, sizeof(ip), "[<%p>]",
574 (void *)class->contention_point[i]);
575 seq_printf(m, "%40s %14lu %29s %s\n", name,
576 stats->contention_point[i],
577 ip, sym);
578 }
c7e78cff
PZ		 579 for (i = 0; i < LOCKSTAT_POINTS; i++) {
580 char sym[KSYM_SYMBOL_LEN];
581 char ip[32];
582
583 if (class->contending_point[i] == 0)
584 break;
585
586 if (!i)
587 seq_line(m, '-', 40-namelen, namelen);
588
589 sprint_symbol(sym, class->contending_point[i]);
590 snprintf(ip, sizeof(ip), "[<%p>]",
591 (void *)class->contending_point[i]);
592 seq_printf(m, "%40s %14lu %29s %s\n", name,
593 stats->contending_point[i],
594 ip, sym);
595 }
c46261de
PZ		 596 if (i) {
597 seq_puts(m, "\n");
96645678 598 seq_line(m, '.', 0, 40 + 1 + 10 * (14 + 1));
c46261de
PZ		 599 seq_puts(m, "\n");
600 }
601}
602
603static void seq_header(struct seq_file *m)
604{
c7e78cff 605 seq_printf(m, "lock_stat version 0.3\n");
9833f8cb
PZ		 606
607 if (unlikely(!debug_locks))
608 seq_printf(m, "*WARNING* lock debugging disabled!! - possibly due to a lockdep warning\n");
609
96645678
PZ		 610 seq_line(m, '-', 0, 40 + 1 + 10 * (14 + 1));
611 seq_printf(m, "%40s %14s %14s %14s %14s %14s %14s %14s %14s "
612 "%14s %14s\n",
c46261de 613 "class name",
96645678 614 "con-bounces",
c46261de
PZ		 615 "contentions",
616 "waittime-min",
617 "waittime-max",
618 "waittime-total",
96645678 619 "acq-bounces",
c46261de
PZ		 620 "acquisitions",
621 "holdtime-min",
622 "holdtime-max",
623 "holdtime-total");
96645678 624 seq_line(m, '-', 0, 40 + 1 + 10 * (14 + 1));
c46261de
PZ		 625 seq_printf(m, "\n");
626}
627
628static void *ls_start(struct seq_file *m, loff_t *pos)
629{
630 struct lock_stat_seq *data = m->private;
631
94c61c0a
TP		 632 if (*pos == 0)
633 return SEQ_START_TOKEN;
c46261de 634
94c61c0a
TP		 635 data->iter = data->stats + *pos;
636 if (data->iter >= data->iter_end)
4b32d0a4
PZ		 637 data->iter = NULL;
638
c46261de
PZ		 639 return data->iter;
640}
641
642static void *ls_next(struct seq_file *m, void *v, loff_t *pos)
643{
644 struct lock_stat_seq *data = m->private;
645
646 (*pos)++;
647
94c61c0a
TP		 648 if (v == SEQ_START_TOKEN)
649 data->iter = data->stats;
650 else {
651 data->iter = v;
652 data->iter++;
653 }
654
c46261de
PZ		 655 if (data->iter == data->iter_end)
656 data->iter = NULL;
657
658 return data->iter;
659}
660
661static void ls_stop(struct seq_file *m, void *v)
662{
663}
664
665static int ls_show(struct seq_file *m, void *v)
666{
94c61c0a
TP		 667 if (v == SEQ_START_TOKEN)
668 seq_header(m);
669 else
670 seq_stats(m, v);
c46261de 671
c46261de
PZ		 672 return 0;
673}
674
675static struct seq_operations lockstat_ops = {
676 .start = ls_start,
677 .next = ls_next,
678 .stop = ls_stop,
679 .show = ls_show,
680};
681
682static int lock_stat_open(struct inode *inode, struct file *file)
683{
684 int res;
685 struct lock_class *class;
686 struct lock_stat_seq *data = vmalloc(sizeof(struct lock_stat_seq));
687
688 if (!data)
689 return -ENOMEM;
690
691 res = seq_open(file, &lockstat_ops);
692 if (!res) {
693 struct lock_stat_data *iter = data->stats;
694 struct seq_file *m = file->private_data;
695
696 data->iter = iter;
697 list_for_each_entry(class, &all_lock_classes, lock_entry) {
698 iter->class = class;
699 iter->stats = lock_stats(class);
700 iter++;
701 }
702 data->iter_end = iter;
703
704 sort(data->stats, data->iter_end - data->iter,
705 sizeof(struct lock_stat_data),
706 lock_stat_cmp, NULL);
707
708 m->private = data;
709 } else
710 vfree(data);
711
712 return res;
713}
714
715static ssize_t lock_stat_write(struct file *file, const char __user *buf,
716 size_t count, loff_t *ppos)
717{
718 struct lock_class *class;
719 char c;
720
721 if (count) {
722 if (get_user(c, buf))
723 return -EFAULT;
724
725 if (c != '0')
726 return count;
727
728 list_for_each_entry(class, &all_lock_classes, lock_entry)
729 clear_lock_stats(class);
730 }
731 return count;
732}
733
734static int lock_stat_release(struct inode *inode, struct file *file)
735{
736 struct seq_file *seq = file->private_data;
737
738 vfree(seq->private);
739 seq->private = NULL;
740 return seq_release(inode, file);
741}
742
743static const struct file_operations proc_lock_stat_operations = {
744 .open = lock_stat_open,
745 .write = lock_stat_write,
746 .read = seq_read,
747 .llseek = seq_lseek,
748 .release = lock_stat_release,
749};
750#endif /* CONFIG_LOCK_STAT */
751
a8f24a39
IM		 752static int __init lockdep_proc_init(void)
753{
c33fff0a 754 proc_create("lockdep", S_IRUSR, NULL, &proc_lockdep_operations);
cd1a28e8 755#ifdef CONFIG_PROVE_LOCKING
443cd507
HY		 756 proc_create("lockdep_chains", S_IRUSR, NULL,
757 &proc_lockdep_chains_operations);
cd1a28e8 758#endif
c33fff0a
DL		 759 proc_create("lockdep_stats", S_IRUSR, NULL,
760 &proc_lockdep_stats_operations);
a8f24a39 761
c46261de 762#ifdef CONFIG_LOCK_STAT
c33fff0a 763 proc_create("lock_stat", S_IRUSR, NULL, &proc_lock_stat_operations);
c46261de
PZ		 764#endif
765
a8f24a39
IM		 766 return 0;
767}
768
769__initcall(lockdep_proc_init);
770
Linux 6.x block layer and io_uring tree(s)