Commit | Line | Data |
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b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
a8f24a39 IM |
2 | /* |
3 | * kernel/lockdep_proc.c | |
4 | * | |
5 | * Runtime locking correctness validator | |
6 | * | |
7 | * Started by Ingo Molnar: | |
8 | * | |
4b32d0a4 | 9 | * Copyright (C) 2006,2007 Red Hat, Inc., Ingo Molnar <mingo@redhat.com> |
90eec103 | 10 | * Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra |
a8f24a39 IM |
11 | * |
12 | * Code for /proc/lockdep and /proc/lockdep_stats: | |
13 | * | |
14 | */ | |
9984de1a | 15 | #include <linux/export.h> |
a8f24a39 IM |
16 | #include <linux/proc_fs.h> |
17 | #include <linux/seq_file.h> | |
18 | #include <linux/kallsyms.h> | |
19 | #include <linux/debug_locks.h> | |
c46261de PZ |
20 | #include <linux/vmalloc.h> |
21 | #include <linux/sort.h> | |
7c0f6ba6 | 22 | #include <linux/uaccess.h> |
c46261de | 23 | #include <asm/div64.h> |
a8f24a39 IM |
24 | |
25 | #include "lockdep_internals.h" | |
26 | ||
fb7275ac WL |
27 | /* |
28 | * Since iteration of lock_classes is done without holding the lockdep lock, | |
29 | * it is not safe to iterate all_lock_classes list directly as the iteration | |
30 | * may branch off to free_lock_classes or the zapped list. Iteration is done | |
31 | * directly on the lock_classes array by checking the lock_classes_in_use | |
32 | * bitmap and max_lock_class_idx. | |
33 | */ | |
34 | #define iterate_lock_classes(idx, class) \ | |
35 | for (idx = 0, class = lock_classes; idx <= max_lock_class_idx; \ | |
36 | idx++, class++) | |
37 | ||
a8f24a39 IM |
38 | static void *l_next(struct seq_file *m, void *v, loff_t *pos) |
39 | { | |
fb7275ac WL |
40 | struct lock_class *class = v; |
41 | ||
42 | ++class; | |
43 | *pos = class - lock_classes; | |
44 | return (*pos > max_lock_class_idx) ? NULL : class; | |
a8f24a39 IM |
45 | } |
46 | ||
47 | static void *l_start(struct seq_file *m, loff_t *pos) | |
48 | { | |
fb7275ac WL |
49 | unsigned long idx = *pos; |
50 | ||
51 | if (idx > max_lock_class_idx) | |
52 | return NULL; | |
53 | return lock_classes + idx; | |
a8f24a39 IM |
54 | } |
55 | ||
56 | static void l_stop(struct seq_file *m, void *v) | |
57 | { | |
58 | } | |
59 | ||
068135e6 JB |
60 | static void print_name(struct seq_file *m, struct lock_class *class) |
61 | { | |
99fb4a12 | 62 | char str[KSYM_NAME_LEN]; |
068135e6 JB |
63 | const char *name = class->name; |
64 | ||
65 | if (!name) { | |
66 | name = __get_key_name(class->key, str); | |
67 | seq_printf(m, "%s", name); | |
68 | } else{ | |
69 | seq_printf(m, "%s", name); | |
70 | if (class->name_version > 1) | |
71 | seq_printf(m, "#%d", class->name_version); | |
72 | if (class->subclass) | |
73 | seq_printf(m, "/%d", class->subclass); | |
74 | } | |
75 | } | |
76 | ||
a8f24a39 IM |
77 | static int l_show(struct seq_file *m, void *v) |
78 | { | |
fb7275ac | 79 | struct lock_class *class = v; |
068135e6 | 80 | struct lock_list *entry; |
f510b233 | 81 | char usage[LOCK_USAGE_CHARS]; |
fb7275ac | 82 | int idx = class - lock_classes; |
a8f24a39 | 83 | |
fb7275ac | 84 | if (v == lock_classes) |
94c61c0a | 85 | seq_printf(m, "all lock classes:\n"); |
fb7275ac WL |
86 | |
87 | if (!test_bit(idx, lock_classes_in_use)) | |
94c61c0a | 88 | return 0; |
94c61c0a | 89 | |
a8f24a39 IM |
90 | seq_printf(m, "%p", class->key); |
91 | #ifdef CONFIG_DEBUG_LOCKDEP | |
8ca2b56c | 92 | seq_printf(m, " OPS:%8ld", debug_class_ops_read(class)); |
a8f24a39 | 93 | #endif |
4840ce22 XS |
94 | if (IS_ENABLED(CONFIG_PROVE_LOCKING)) { |
95 | seq_printf(m, " FD:%5ld", lockdep_count_forward_deps(class)); | |
96 | seq_printf(m, " BD:%5ld", lockdep_count_backward_deps(class)); | |
a8f24a39 | 97 | |
4840ce22 XS |
98 | get_usage_chars(class, usage); |
99 | seq_printf(m, " %s", usage); | |
100 | } | |
a8f24a39 | 101 | |
068135e6 JB |
102 | seq_printf(m, ": "); |
103 | print_name(m, class); | |
104 | seq_puts(m, "\n"); | |
105 | ||
4840ce22 XS |
106 | if (IS_ENABLED(CONFIG_PROVE_LOCKING)) { |
107 | list_for_each_entry(entry, &class->locks_after, entry) { | |
108 | if (entry->distance == 1) { | |
109 | seq_printf(m, " -> [%p] ", entry->class->key); | |
110 | print_name(m, entry->class); | |
111 | seq_puts(m, "\n"); | |
112 | } | |
068135e6 | 113 | } |
4840ce22 | 114 | seq_puts(m, "\n"); |
a8f24a39 | 115 | } |
a8f24a39 IM |
116 | |
117 | return 0; | |
118 | } | |
119 | ||
15ad7cdc | 120 | static const struct seq_operations lockdep_ops = { |
a8f24a39 IM |
121 | .start = l_start, |
122 | .next = l_next, | |
123 | .stop = l_stop, | |
124 | .show = l_show, | |
125 | }; | |
126 | ||
cd1a28e8 | 127 | #ifdef CONFIG_PROVE_LOCKING |
443cd507 HY |
128 | static void *lc_start(struct seq_file *m, loff_t *pos) |
129 | { | |
2212684a BVA |
130 | if (*pos < 0) |
131 | return NULL; | |
132 | ||
443cd507 HY |
133 | if (*pos == 0) |
134 | return SEQ_START_TOKEN; | |
135 | ||
2212684a | 136 | return lock_chains + (*pos - 1); |
443cd507 HY |
137 | } |
138 | ||
12aac19d LZ |
139 | static void *lc_next(struct seq_file *m, void *v, loff_t *pos) |
140 | { | |
2212684a | 141 | *pos = lockdep_next_lockchain(*pos - 1) + 1; |
12aac19d LZ |
142 | return lc_start(m, pos); |
143 | } | |
144 | ||
443cd507 HY |
145 | static void lc_stop(struct seq_file *m, void *v) |
146 | { | |
147 | } | |
148 | ||
149 | static int lc_show(struct seq_file *m, void *v) | |
150 | { | |
151 | struct lock_chain *chain = v; | |
152 | struct lock_class *class; | |
153 | int i; | |
b9875e98 WL |
154 | static const char * const irq_strs[] = { |
155 | [0] = "0", | |
156 | [LOCK_CHAIN_HARDIRQ_CONTEXT] = "hardirq", | |
157 | [LOCK_CHAIN_SOFTIRQ_CONTEXT] = "softirq", | |
158 | [LOCK_CHAIN_SOFTIRQ_CONTEXT| | |
159 | LOCK_CHAIN_HARDIRQ_CONTEXT] = "hardirq|softirq", | |
160 | }; | |
443cd507 HY |
161 | |
162 | if (v == SEQ_START_TOKEN) { | |
810507fe | 163 | if (!nr_free_chain_hlocks) |
75dd602a | 164 | seq_printf(m, "(buggered) "); |
443cd507 HY |
165 | seq_printf(m, "all lock chains:\n"); |
166 | return 0; | |
167 | } | |
168 | ||
b9875e98 | 169 | seq_printf(m, "irq_context: %s\n", irq_strs[chain->irq_context]); |
443cd507 HY |
170 | |
171 | for (i = 0; i < chain->depth; i++) { | |
172 | class = lock_chain_get_class(chain, i); | |
8bfe0298 RV |
173 | if (!class->key) |
174 | continue; | |
175 | ||
443cd507 HY |
176 | seq_printf(m, "[%p] ", class->key); |
177 | print_name(m, class); | |
178 | seq_puts(m, "\n"); | |
179 | } | |
180 | seq_puts(m, "\n"); | |
181 | ||
182 | return 0; | |
183 | } | |
184 | ||
185 | static const struct seq_operations lockdep_chains_ops = { | |
186 | .start = lc_start, | |
187 | .next = lc_next, | |
188 | .stop = lc_stop, | |
189 | .show = lc_show, | |
190 | }; | |
cd1a28e8 | 191 | #endif /* CONFIG_PROVE_LOCKING */ |
443cd507 | 192 | |
a8f24a39 IM |
193 | static void lockdep_stats_debug_show(struct seq_file *m) |
194 | { | |
195 | #ifdef CONFIG_DEBUG_LOCKDEP | |
bd6d29c2 FW |
196 | unsigned long long hi1 = debug_atomic_read(hardirqs_on_events), |
197 | hi2 = debug_atomic_read(hardirqs_off_events), | |
198 | hr1 = debug_atomic_read(redundant_hardirqs_on), | |
199 | hr2 = debug_atomic_read(redundant_hardirqs_off), | |
200 | si1 = debug_atomic_read(softirqs_on_events), | |
201 | si2 = debug_atomic_read(softirqs_off_events), | |
202 | sr1 = debug_atomic_read(redundant_softirqs_on), | |
203 | sr2 = debug_atomic_read(redundant_softirqs_off); | |
204 | ||
205 | seq_printf(m, " chain lookup misses: %11llu\n", | |
206 | debug_atomic_read(chain_lookup_misses)); | |
207 | seq_printf(m, " chain lookup hits: %11llu\n", | |
208 | debug_atomic_read(chain_lookup_hits)); | |
209 | seq_printf(m, " cyclic checks: %11llu\n", | |
210 | debug_atomic_read(nr_cyclic_checks)); | |
ae813308 PZ |
211 | seq_printf(m, " redundant checks: %11llu\n", |
212 | debug_atomic_read(nr_redundant_checks)); | |
213 | seq_printf(m, " redundant links: %11llu\n", | |
214 | debug_atomic_read(nr_redundant)); | |
bd6d29c2 FW |
215 | seq_printf(m, " find-mask forwards checks: %11llu\n", |
216 | debug_atomic_read(nr_find_usage_forwards_checks)); | |
217 | seq_printf(m, " find-mask backwards checks: %11llu\n", | |
218 | debug_atomic_read(nr_find_usage_backwards_checks)); | |
219 | ||
220 | seq_printf(m, " hardirq on events: %11llu\n", hi1); | |
221 | seq_printf(m, " hardirq off events: %11llu\n", hi2); | |
222 | seq_printf(m, " redundant hardirq ons: %11llu\n", hr1); | |
223 | seq_printf(m, " redundant hardirq offs: %11llu\n", hr2); | |
224 | seq_printf(m, " softirq on events: %11llu\n", si1); | |
225 | seq_printf(m, " softirq off events: %11llu\n", si2); | |
226 | seq_printf(m, " redundant softirq ons: %11llu\n", sr1); | |
227 | seq_printf(m, " redundant softirq offs: %11llu\n", sr2); | |
a8f24a39 IM |
228 | #endif |
229 | } | |
230 | ||
231 | static int lockdep_stats_show(struct seq_file *m, void *v) | |
232 | { | |
a8f24a39 IM |
233 | unsigned long nr_unused = 0, nr_uncategorized = 0, |
234 | nr_irq_safe = 0, nr_irq_unsafe = 0, | |
235 | nr_softirq_safe = 0, nr_softirq_unsafe = 0, | |
236 | nr_hardirq_safe = 0, nr_hardirq_unsafe = 0, | |
237 | nr_irq_read_safe = 0, nr_irq_read_unsafe = 0, | |
238 | nr_softirq_read_safe = 0, nr_softirq_read_unsafe = 0, | |
239 | nr_hardirq_read_safe = 0, nr_hardirq_read_unsafe = 0, | |
dec29608 | 240 | sum_forward_deps = 0; |
a8f24a39 | 241 | |
68d41d8c | 242 | #ifdef CONFIG_PROVE_LOCKING |
68037aa7 | 243 | struct lock_class *class; |
fb7275ac | 244 | unsigned long idx; |
68037aa7 | 245 | |
fb7275ac WL |
246 | iterate_lock_classes(idx, class) { |
247 | if (!test_bit(idx, lock_classes_in_use)) | |
248 | continue; | |
a8f24a39 IM |
249 | |
250 | if (class->usage_mask == 0) | |
251 | nr_unused++; | |
252 | if (class->usage_mask == LOCKF_USED) | |
253 | nr_uncategorized++; | |
254 | if (class->usage_mask & LOCKF_USED_IN_IRQ) | |
255 | nr_irq_safe++; | |
4fc95e86 | 256 | if (class->usage_mask & LOCKF_ENABLED_IRQ) |
a8f24a39 IM |
257 | nr_irq_unsafe++; |
258 | if (class->usage_mask & LOCKF_USED_IN_SOFTIRQ) | |
259 | nr_softirq_safe++; | |
4fc95e86 | 260 | if (class->usage_mask & LOCKF_ENABLED_SOFTIRQ) |
a8f24a39 IM |
261 | nr_softirq_unsafe++; |
262 | if (class->usage_mask & LOCKF_USED_IN_HARDIRQ) | |
263 | nr_hardirq_safe++; | |
4fc95e86 | 264 | if (class->usage_mask & LOCKF_ENABLED_HARDIRQ) |
a8f24a39 IM |
265 | nr_hardirq_unsafe++; |
266 | if (class->usage_mask & LOCKF_USED_IN_IRQ_READ) | |
267 | nr_irq_read_safe++; | |
4fc95e86 | 268 | if (class->usage_mask & LOCKF_ENABLED_IRQ_READ) |
a8f24a39 IM |
269 | nr_irq_read_unsafe++; |
270 | if (class->usage_mask & LOCKF_USED_IN_SOFTIRQ_READ) | |
271 | nr_softirq_read_safe++; | |
4fc95e86 | 272 | if (class->usage_mask & LOCKF_ENABLED_SOFTIRQ_READ) |
a8f24a39 IM |
273 | nr_softirq_read_unsafe++; |
274 | if (class->usage_mask & LOCKF_USED_IN_HARDIRQ_READ) | |
275 | nr_hardirq_read_safe++; | |
4fc95e86 | 276 | if (class->usage_mask & LOCKF_ENABLED_HARDIRQ_READ) |
a8f24a39 IM |
277 | nr_hardirq_read_unsafe++; |
278 | ||
419ca3f1 | 279 | sum_forward_deps += lockdep_count_forward_deps(class); |
a8f24a39 | 280 | } |
fb7275ac | 281 | |
501b9ebf | 282 | #ifdef CONFIG_DEBUG_LOCKDEP |
bd6d29c2 | 283 | DEBUG_LOCKS_WARN_ON(debug_atomic_read(nr_unused_locks) != nr_unused); |
68d41d8c YD |
284 | #endif |
285 | ||
a8f24a39 IM |
286 | #endif |
287 | seq_printf(m, " lock-classes: %11lu [max: %lu]\n", | |
288 | nr_lock_classes, MAX_LOCKDEP_KEYS); | |
289 | seq_printf(m, " direct dependencies: %11lu [max: %lu]\n", | |
290 | nr_list_entries, MAX_LOCKDEP_ENTRIES); | |
291 | seq_printf(m, " indirect dependencies: %11lu\n", | |
292 | sum_forward_deps); | |
293 | ||
294 | /* | |
295 | * Total number of dependencies: | |
296 | * | |
297 | * All irq-safe locks may nest inside irq-unsafe locks, | |
298 | * plus all the other known dependencies: | |
299 | */ | |
300 | seq_printf(m, " all direct dependencies: %11lu\n", | |
301 | nr_irq_unsafe * nr_irq_safe + | |
302 | nr_hardirq_unsafe * nr_hardirq_safe + | |
303 | nr_list_entries); | |
304 | ||
8e18257d | 305 | #ifdef CONFIG_PROVE_LOCKING |
a8f24a39 | 306 | seq_printf(m, " dependency chains: %11lu [max: %lu]\n", |
2212684a | 307 | lock_chain_count(), MAX_LOCKDEP_CHAINS); |
810507fe WL |
308 | seq_printf(m, " dependency chain hlocks used: %11lu [max: %lu]\n", |
309 | MAX_LOCKDEP_CHAIN_HLOCKS - | |
310 | (nr_free_chain_hlocks + nr_lost_chain_hlocks), | |
311 | MAX_LOCKDEP_CHAIN_HLOCKS); | |
312 | seq_printf(m, " dependency chain hlocks lost: %11u\n", | |
313 | nr_lost_chain_hlocks); | |
8e18257d | 314 | #endif |
a8f24a39 IM |
315 | |
316 | #ifdef CONFIG_TRACE_IRQFLAGS | |
317 | seq_printf(m, " in-hardirq chains: %11u\n", | |
318 | nr_hardirq_chains); | |
319 | seq_printf(m, " in-softirq chains: %11u\n", | |
320 | nr_softirq_chains); | |
321 | #endif | |
322 | seq_printf(m, " in-process chains: %11u\n", | |
323 | nr_process_chains); | |
324 | seq_printf(m, " stack-trace entries: %11lu [max: %lu]\n", | |
325 | nr_stack_trace_entries, MAX_STACK_TRACE_ENTRIES); | |
8c779229 | 326 | #if defined(CONFIG_TRACE_IRQFLAGS) && defined(CONFIG_PROVE_LOCKING) |
a030f976 | 327 | seq_printf(m, " number of stack traces: %11llu\n", |
8c779229 | 328 | lockdep_stack_trace_count()); |
a030f976 | 329 | seq_printf(m, " number of stack hash chains: %11llu\n", |
8c779229 BVA |
330 | lockdep_stack_hash_count()); |
331 | #endif | |
a8f24a39 IM |
332 | seq_printf(m, " combined max dependencies: %11u\n", |
333 | (nr_hardirq_chains + 1) * | |
334 | (nr_softirq_chains + 1) * | |
335 | (nr_process_chains + 1) | |
336 | ); | |
337 | seq_printf(m, " hardirq-safe locks: %11lu\n", | |
338 | nr_hardirq_safe); | |
339 | seq_printf(m, " hardirq-unsafe locks: %11lu\n", | |
340 | nr_hardirq_unsafe); | |
341 | seq_printf(m, " softirq-safe locks: %11lu\n", | |
342 | nr_softirq_safe); | |
343 | seq_printf(m, " softirq-unsafe locks: %11lu\n", | |
344 | nr_softirq_unsafe); | |
345 | seq_printf(m, " irq-safe locks: %11lu\n", | |
346 | nr_irq_safe); | |
347 | seq_printf(m, " irq-unsafe locks: %11lu\n", | |
348 | nr_irq_unsafe); | |
349 | ||
350 | seq_printf(m, " hardirq-read-safe locks: %11lu\n", | |
351 | nr_hardirq_read_safe); | |
352 | seq_printf(m, " hardirq-read-unsafe locks: %11lu\n", | |
353 | nr_hardirq_read_unsafe); | |
354 | seq_printf(m, " softirq-read-safe locks: %11lu\n", | |
355 | nr_softirq_read_safe); | |
356 | seq_printf(m, " softirq-read-unsafe locks: %11lu\n", | |
357 | nr_softirq_read_unsafe); | |
358 | seq_printf(m, " irq-read-safe locks: %11lu\n", | |
359 | nr_irq_read_safe); | |
360 | seq_printf(m, " irq-read-unsafe locks: %11lu\n", | |
361 | nr_irq_read_unsafe); | |
362 | ||
363 | seq_printf(m, " uncategorized locks: %11lu\n", | |
364 | nr_uncategorized); | |
365 | seq_printf(m, " unused locks: %11lu\n", | |
366 | nr_unused); | |
367 | seq_printf(m, " max locking depth: %11u\n", | |
368 | max_lockdep_depth); | |
bbfa2622 | 369 | #ifdef CONFIG_PROVE_LOCKING |
12f3dfd0 ML |
370 | seq_printf(m, " max bfs queue depth: %11u\n", |
371 | max_bfs_queue_depth); | |
bbfa2622 | 372 | #endif |
fb7275ac WL |
373 | seq_printf(m, " max lock class index: %11lu\n", |
374 | max_lock_class_idx); | |
a8f24a39 IM |
375 | lockdep_stats_debug_show(m); |
376 | seq_printf(m, " debug_locks: %11u\n", | |
377 | debug_locks); | |
378 | ||
1d44bcb4 | 379 | /* |
e2db7592 | 380 | * Zapped classes and lockdep data buffers reuse statistics. |
1d44bcb4 WL |
381 | */ |
382 | seq_puts(m, "\n"); | |
383 | seq_printf(m, " zapped classes: %11lu\n", | |
384 | nr_zapped_classes); | |
797b82eb WL |
385 | #ifdef CONFIG_PROVE_LOCKING |
386 | seq_printf(m, " zapped lock chains: %11lu\n", | |
387 | nr_zapped_lock_chains); | |
810507fe WL |
388 | seq_printf(m, " large chain blocks: %11u\n", |
389 | nr_large_chain_blocks); | |
797b82eb | 390 | #endif |
a8f24a39 IM |
391 | return 0; |
392 | } | |
393 | ||
c46261de PZ |
394 | #ifdef CONFIG_LOCK_STAT |
395 | ||
396 | struct lock_stat_data { | |
397 | struct lock_class *class; | |
398 | struct lock_class_stats stats; | |
399 | }; | |
400 | ||
401 | struct lock_stat_seq { | |
c46261de PZ |
402 | struct lock_stat_data *iter_end; |
403 | struct lock_stat_data stats[MAX_LOCKDEP_KEYS]; | |
404 | }; | |
405 | ||
406 | /* | |
407 | * sort on absolute number of contentions | |
408 | */ | |
409 | static int lock_stat_cmp(const void *l, const void *r) | |
410 | { | |
411 | const struct lock_stat_data *dl = l, *dr = r; | |
412 | unsigned long nl, nr; | |
413 | ||
414 | nl = dl->stats.read_waittime.nr + dl->stats.write_waittime.nr; | |
415 | nr = dr->stats.read_waittime.nr + dr->stats.write_waittime.nr; | |
416 | ||
417 | return nr - nl; | |
418 | } | |
419 | ||
420 | static void seq_line(struct seq_file *m, char c, int offset, int length) | |
421 | { | |
422 | int i; | |
423 | ||
424 | for (i = 0; i < offset; i++) | |
425 | seq_puts(m, " "); | |
426 | for (i = 0; i < length; i++) | |
427 | seq_printf(m, "%c", c); | |
428 | seq_puts(m, "\n"); | |
429 | } | |
430 | ||
431 | static void snprint_time(char *buf, size_t bufsiz, s64 nr) | |
432 | { | |
6918bc5c PZ |
433 | s64 div; |
434 | s32 rem; | |
c46261de | 435 | |
2189459d | 436 | nr += 5; /* for display rounding */ |
6918bc5c PZ |
437 | div = div_s64_rem(nr, 1000, &rem); |
438 | snprintf(buf, bufsiz, "%lld.%02d", (long long)div, (int)rem/10); | |
c46261de PZ |
439 | } |
440 | ||
441 | static void seq_time(struct seq_file *m, s64 time) | |
442 | { | |
443 | char num[15]; | |
444 | ||
445 | snprint_time(num, sizeof(num), time); | |
446 | seq_printf(m, " %14s", num); | |
447 | } | |
448 | ||
449 | static void seq_lock_time(struct seq_file *m, struct lock_time *lt) | |
450 | { | |
451 | seq_printf(m, "%14lu", lt->nr); | |
452 | seq_time(m, lt->min); | |
453 | seq_time(m, lt->max); | |
454 | seq_time(m, lt->total); | |
a7ef9b28 | 455 | seq_time(m, lt->nr ? div64_u64(lt->total, lt->nr) : 0); |
c46261de PZ |
456 | } |
457 | ||
458 | static void seq_stats(struct seq_file *m, struct lock_stat_data *data) | |
459 | { | |
364f6afc | 460 | const struct lockdep_subclass_key *ckey; |
c46261de | 461 | struct lock_class_stats *stats; |
cee34d88 PZ |
462 | struct lock_class *class; |
463 | const char *cname; | |
c46261de | 464 | int i, namelen; |
cee34d88 | 465 | char name[39]; |
c46261de PZ |
466 | |
467 | class = data->class; | |
468 | stats = &data->stats; | |
469 | ||
d38e1d5a PZ |
470 | namelen = 38; |
471 | if (class->name_version > 1) | |
472 | namelen -= 2; /* XXX truncates versions > 9 */ | |
473 | if (class->subclass) | |
474 | namelen -= 2; | |
475 | ||
cee34d88 PZ |
476 | rcu_read_lock_sched(); |
477 | cname = rcu_dereference_sched(class->name); | |
478 | ckey = rcu_dereference_sched(class->key); | |
479 | ||
480 | if (!cname && !ckey) { | |
481 | rcu_read_unlock_sched(); | |
482 | return; | |
483 | ||
484 | } else if (!cname) { | |
d38e1d5a PZ |
485 | char str[KSYM_NAME_LEN]; |
486 | const char *key_name; | |
487 | ||
cee34d88 | 488 | key_name = __get_key_name(ckey, str); |
d38e1d5a PZ |
489 | snprintf(name, namelen, "%s", key_name); |
490 | } else { | |
cee34d88 | 491 | snprintf(name, namelen, "%s", cname); |
d38e1d5a | 492 | } |
cee34d88 PZ |
493 | rcu_read_unlock_sched(); |
494 | ||
c46261de | 495 | namelen = strlen(name); |
d38e1d5a PZ |
496 | if (class->name_version > 1) { |
497 | snprintf(name+namelen, 3, "#%d", class->name_version); | |
498 | namelen += 2; | |
499 | } | |
500 | if (class->subclass) { | |
501 | snprintf(name+namelen, 3, "/%d", class->subclass); | |
502 | namelen += 2; | |
503 | } | |
c46261de PZ |
504 | |
505 | if (stats->write_holdtime.nr) { | |
506 | if (stats->read_holdtime.nr) | |
507 | seq_printf(m, "%38s-W:", name); | |
508 | else | |
509 | seq_printf(m, "%40s:", name); | |
510 | ||
96645678 | 511 | seq_printf(m, "%14lu ", stats->bounces[bounce_contended_write]); |
c46261de | 512 | seq_lock_time(m, &stats->write_waittime); |
96645678 | 513 | seq_printf(m, " %14lu ", stats->bounces[bounce_acquired_write]); |
c46261de PZ |
514 | seq_lock_time(m, &stats->write_holdtime); |
515 | seq_puts(m, "\n"); | |
516 | } | |
517 | ||
518 | if (stats->read_holdtime.nr) { | |
519 | seq_printf(m, "%38s-R:", name); | |
96645678 | 520 | seq_printf(m, "%14lu ", stats->bounces[bounce_contended_read]); |
c46261de | 521 | seq_lock_time(m, &stats->read_waittime); |
96645678 | 522 | seq_printf(m, " %14lu ", stats->bounces[bounce_acquired_read]); |
c46261de PZ |
523 | seq_lock_time(m, &stats->read_holdtime); |
524 | seq_puts(m, "\n"); | |
525 | } | |
526 | ||
527 | if (stats->read_waittime.nr + stats->write_waittime.nr == 0) | |
528 | return; | |
529 | ||
530 | if (stats->read_holdtime.nr) | |
531 | namelen += 2; | |
532 | ||
c7e78cff | 533 | for (i = 0; i < LOCKSTAT_POINTS; i++) { |
c46261de PZ |
534 | char ip[32]; |
535 | ||
536 | if (class->contention_point[i] == 0) | |
537 | break; | |
538 | ||
539 | if (!i) | |
540 | seq_line(m, '-', 40-namelen, namelen); | |
541 | ||
c46261de PZ |
542 | snprintf(ip, sizeof(ip), "[<%p>]", |
543 | (void *)class->contention_point[i]); | |
3cf9b85b JP |
544 | seq_printf(m, "%40s %14lu %29s %pS\n", |
545 | name, stats->contention_point[i], | |
546 | ip, (void *)class->contention_point[i]); | |
c46261de | 547 | } |
c7e78cff | 548 | for (i = 0; i < LOCKSTAT_POINTS; i++) { |
c7e78cff PZ |
549 | char ip[32]; |
550 | ||
551 | if (class->contending_point[i] == 0) | |
552 | break; | |
553 | ||
554 | if (!i) | |
555 | seq_line(m, '-', 40-namelen, namelen); | |
556 | ||
c7e78cff PZ |
557 | snprintf(ip, sizeof(ip), "[<%p>]", |
558 | (void *)class->contending_point[i]); | |
3cf9b85b JP |
559 | seq_printf(m, "%40s %14lu %29s %pS\n", |
560 | name, stats->contending_point[i], | |
561 | ip, (void *)class->contending_point[i]); | |
c7e78cff | 562 | } |
c46261de PZ |
563 | if (i) { |
564 | seq_puts(m, "\n"); | |
1232e380 | 565 | seq_line(m, '.', 0, 40 + 1 + 12 * (14 + 1)); |
c46261de PZ |
566 | seq_puts(m, "\n"); |
567 | } | |
568 | } | |
569 | ||
570 | static void seq_header(struct seq_file *m) | |
571 | { | |
1232e380 | 572 | seq_puts(m, "lock_stat version 0.4\n"); |
9833f8cb PZ |
573 | |
574 | if (unlikely(!debug_locks)) | |
575 | seq_printf(m, "*WARNING* lock debugging disabled!! - possibly due to a lockdep warning\n"); | |
576 | ||
1232e380 DB |
577 | seq_line(m, '-', 0, 40 + 1 + 12 * (14 + 1)); |
578 | seq_printf(m, "%40s %14s %14s %14s %14s %14s %14s %14s %14s %14s %14s " | |
96645678 | 579 | "%14s %14s\n", |
c46261de | 580 | "class name", |
96645678 | 581 | "con-bounces", |
c46261de PZ |
582 | "contentions", |
583 | "waittime-min", | |
584 | "waittime-max", | |
585 | "waittime-total", | |
1232e380 | 586 | "waittime-avg", |
96645678 | 587 | "acq-bounces", |
c46261de PZ |
588 | "acquisitions", |
589 | "holdtime-min", | |
590 | "holdtime-max", | |
1232e380 DB |
591 | "holdtime-total", |
592 | "holdtime-avg"); | |
593 | seq_line(m, '-', 0, 40 + 1 + 12 * (14 + 1)); | |
c46261de PZ |
594 | seq_printf(m, "\n"); |
595 | } | |
596 | ||
597 | static void *ls_start(struct seq_file *m, loff_t *pos) | |
598 | { | |
599 | struct lock_stat_seq *data = m->private; | |
96004bb2 | 600 | struct lock_stat_data *iter; |
c46261de | 601 | |
94c61c0a TP |
602 | if (*pos == 0) |
603 | return SEQ_START_TOKEN; | |
c46261de | 604 | |
96004bb2 LZ |
605 | iter = data->stats + (*pos - 1); |
606 | if (iter >= data->iter_end) | |
607 | iter = NULL; | |
4b32d0a4 | 608 | |
96004bb2 | 609 | return iter; |
c46261de PZ |
610 | } |
611 | ||
612 | static void *ls_next(struct seq_file *m, void *v, loff_t *pos) | |
613 | { | |
c46261de | 614 | (*pos)++; |
96004bb2 | 615 | return ls_start(m, pos); |
c46261de PZ |
616 | } |
617 | ||
618 | static void ls_stop(struct seq_file *m, void *v) | |
619 | { | |
620 | } | |
621 | ||
622 | static int ls_show(struct seq_file *m, void *v) | |
623 | { | |
94c61c0a TP |
624 | if (v == SEQ_START_TOKEN) |
625 | seq_header(m); | |
626 | else | |
627 | seq_stats(m, v); | |
c46261de | 628 | |
c46261de PZ |
629 | return 0; |
630 | } | |
631 | ||
88e9d34c | 632 | static const struct seq_operations lockstat_ops = { |
c46261de PZ |
633 | .start = ls_start, |
634 | .next = ls_next, | |
635 | .stop = ls_stop, | |
636 | .show = ls_show, | |
637 | }; | |
638 | ||
639 | static int lock_stat_open(struct inode *inode, struct file *file) | |
640 | { | |
641 | int res; | |
642 | struct lock_class *class; | |
643 | struct lock_stat_seq *data = vmalloc(sizeof(struct lock_stat_seq)); | |
644 | ||
645 | if (!data) | |
646 | return -ENOMEM; | |
647 | ||
648 | res = seq_open(file, &lockstat_ops); | |
649 | if (!res) { | |
650 | struct lock_stat_data *iter = data->stats; | |
651 | struct seq_file *m = file->private_data; | |
fb7275ac | 652 | unsigned long idx; |
c46261de | 653 | |
fb7275ac WL |
654 | iterate_lock_classes(idx, class) { |
655 | if (!test_bit(idx, lock_classes_in_use)) | |
656 | continue; | |
c46261de PZ |
657 | iter->class = class; |
658 | iter->stats = lock_stats(class); | |
659 | iter++; | |
660 | } | |
fb7275ac | 661 | |
c46261de PZ |
662 | data->iter_end = iter; |
663 | ||
96004bb2 | 664 | sort(data->stats, data->iter_end - data->stats, |
c46261de PZ |
665 | sizeof(struct lock_stat_data), |
666 | lock_stat_cmp, NULL); | |
667 | ||
668 | m->private = data; | |
669 | } else | |
670 | vfree(data); | |
671 | ||
672 | return res; | |
673 | } | |
674 | ||
675 | static ssize_t lock_stat_write(struct file *file, const char __user *buf, | |
676 | size_t count, loff_t *ppos) | |
677 | { | |
678 | struct lock_class *class; | |
fb7275ac | 679 | unsigned long idx; |
c46261de PZ |
680 | char c; |
681 | ||
682 | if (count) { | |
683 | if (get_user(c, buf)) | |
684 | return -EFAULT; | |
685 | ||
686 | if (c != '0') | |
687 | return count; | |
688 | ||
fb7275ac WL |
689 | iterate_lock_classes(idx, class) { |
690 | if (!test_bit(idx, lock_classes_in_use)) | |
691 | continue; | |
c46261de | 692 | clear_lock_stats(class); |
fb7275ac | 693 | } |
c46261de PZ |
694 | } |
695 | return count; | |
696 | } | |
697 | ||
698 | static int lock_stat_release(struct inode *inode, struct file *file) | |
699 | { | |
700 | struct seq_file *seq = file->private_data; | |
701 | ||
702 | vfree(seq->private); | |
c46261de PZ |
703 | return seq_release(inode, file); |
704 | } | |
705 | ||
97a32539 AD |
706 | static const struct proc_ops lock_stat_proc_ops = { |
707 | .proc_open = lock_stat_open, | |
708 | .proc_write = lock_stat_write, | |
709 | .proc_read = seq_read, | |
710 | .proc_lseek = seq_lseek, | |
711 | .proc_release = lock_stat_release, | |
c46261de PZ |
712 | }; |
713 | #endif /* CONFIG_LOCK_STAT */ | |
714 | ||
a8f24a39 IM |
715 | static int __init lockdep_proc_init(void) |
716 | { | |
fddda2b7 | 717 | proc_create_seq("lockdep", S_IRUSR, NULL, &lockdep_ops); |
cd1a28e8 | 718 | #ifdef CONFIG_PROVE_LOCKING |
fddda2b7 | 719 | proc_create_seq("lockdep_chains", S_IRUSR, NULL, &lockdep_chains_ops); |
cd1a28e8 | 720 | #endif |
3f3942ac | 721 | proc_create_single("lockdep_stats", S_IRUSR, NULL, lockdep_stats_show); |
c46261de | 722 | #ifdef CONFIG_LOCK_STAT |
97a32539 | 723 | proc_create("lock_stat", S_IRUSR | S_IWUSR, NULL, &lock_stat_proc_ops); |
c46261de PZ |
724 | #endif |
725 | ||
a8f24a39 IM |
726 | return 0; |
727 | } | |
728 | ||
729 | __initcall(lockdep_proc_init); | |
730 |