projects/linux·blob v2.6.21 · refs

361 lines · 10.3 KiB

1/*
2 * kernel/lockdep_proc.c
3 *
4 * Runtime locking correctness validator
5 *
6 * Started by Ingo Molnar:
7 *
8 * Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <[email protected]>
9 *
10 * Code for /proc/lockdep and /proc/lockdep_stats:
11 *
12 */
13#include <linux/module.h>
14#include <linux/proc_fs.h>
15#include <linux/seq_file.h>
16#include <linux/kallsyms.h>
17#include <linux/debug_locks.h>
18
19#include "lockdep_internals.h"
20
21static void *l_next(struct seq_file *m, void *v, loff_t *pos)
22{
23 struct lock_class *class = v;
24
25 (*pos)++;
26
27 if (class->lock_entry.next != &all_lock_classes)
28 class = list_entry(class->lock_entry.next, struct lock_class,
29 lock_entry);
30 else
31 class = NULL;
32 m->private = class;
33
34 return class;
35}
36
37static void *l_start(struct seq_file *m, loff_t *pos)
38{
39 struct lock_class *class = m->private;
40
41 if (&class->lock_entry == all_lock_classes.next)
42 seq_printf(m, "all lock classes:\n");
43
44 return class;
45}
46
47static void l_stop(struct seq_file *m, void *v)
48{
49}
50
51static unsigned long count_forward_deps(struct lock_class *class)
52{
53 struct lock_list *entry;
54 unsigned long ret = 1;
55
56 /*
57 * Recurse this class's dependency list:
58 */
59 list_for_each_entry(entry, &class->locks_after, entry)
60 ret += count_forward_deps(entry->class);
61
62 return ret;
63}
64
65static unsigned long count_backward_deps(struct lock_class *class)
66{
67 struct lock_list *entry;
68 unsigned long ret = 1;
69
70 /*
71 * Recurse this class's dependency list:
72 */
73 list_for_each_entry(entry, &class->locks_before, entry)
74 ret += count_backward_deps(entry->class);
75
76 return ret;
77}
78
79static void print_name(struct seq_file *m, struct lock_class *class)
80{
81 char str[128];
82 const char *name = class->name;
83
84 if (!name) {
85 name = __get_key_name(class->key, str);
86 seq_printf(m, "%s", name);
87 } else{
88 seq_printf(m, "%s", name);
89 if (class->name_version > 1)
90 seq_printf(m, "#%d", class->name_version);
91 if (class->subclass)
92 seq_printf(m, "/%d", class->subclass);
93 }
94}
95
96static int l_show(struct seq_file *m, void *v)
97{
98 unsigned long nr_forward_deps, nr_backward_deps;
99 struct lock_class *class = m->private;
100 struct lock_list *entry;
101 char c1, c2, c3, c4;
102
103 seq_printf(m, "%p", class->key);
104#ifdef CONFIG_DEBUG_LOCKDEP
105 seq_printf(m, " OPS:%8ld", class->ops);
106#endif
107 nr_forward_deps = count_forward_deps(class);
108 seq_printf(m, " FD:%5ld", nr_forward_deps);
109
110 nr_backward_deps = count_backward_deps(class);
111 seq_printf(m, " BD:%5ld", nr_backward_deps);
112
113 get_usage_chars(class, &c1, &c2, &c3, &c4);
114 seq_printf(m, " %c%c%c%c", c1, c2, c3, c4);
115
116 seq_printf(m, ": ");
117 print_name(m, class);
118 seq_puts(m, "\n");
119
120 list_for_each_entry(entry, &class->locks_after, entry) {
121 if (entry->distance == 1) {
122 seq_printf(m, " -> [%p] ", entry->class);
123 print_name(m, entry->class);
124 seq_puts(m, "\n");
125 }
126 }
127 seq_puts(m, "\n");
128
129 return 0;
130}
131
132static const struct seq_operations lockdep_ops = {
133 .start = l_start,
134 .next = l_next,
135 .stop = l_stop,
136 .show = l_show,
137};
138
139static int lockdep_open(struct inode *inode, struct file *file)
140{
141 int res = seq_open(file, &lockdep_ops);
142 if (!res) {
143 struct seq_file *m = file->private_data;
144
145 if (!list_empty(&all_lock_classes))
146 m->private = list_entry(all_lock_classes.next,
147 struct lock_class, lock_entry);
148 else
149 m->private = NULL;
150 }
151 return res;
152}
153
154static const struct file_operations proc_lockdep_operations = {
155 .open = lockdep_open,
156 .read = seq_read,
157 .llseek = seq_lseek,
158 .release = seq_release,
159};
160
161static void lockdep_stats_debug_show(struct seq_file *m)
162{
163#ifdef CONFIG_DEBUG_LOCKDEP
164 unsigned int hi1 = debug_atomic_read(&hardirqs_on_events),
165 hi2 = debug_atomic_read(&hardirqs_off_events),
166 hr1 = debug_atomic_read(&redundant_hardirqs_on),
167 hr2 = debug_atomic_read(&redundant_hardirqs_off),
168 si1 = debug_atomic_read(&softirqs_on_events),
169 si2 = debug_atomic_read(&softirqs_off_events),
170 sr1 = debug_atomic_read(&redundant_softirqs_on),
171 sr2 = debug_atomic_read(&redundant_softirqs_off);
172
173 seq_printf(m, " chain lookup misses: %11u\n",
174 debug_atomic_read(&chain_lookup_misses));
175 seq_printf(m, " chain lookup hits: %11u\n",
176 debug_atomic_read(&chain_lookup_hits));
177 seq_printf(m, " cyclic checks: %11u\n",
178 debug_atomic_read(&nr_cyclic_checks));
179 seq_printf(m, " cyclic-check recursions: %11u\n",
180 debug_atomic_read(&nr_cyclic_check_recursions));
181 seq_printf(m, " find-mask forwards checks: %11u\n",
182 debug_atomic_read(&nr_find_usage_forwards_checks));
183 seq_printf(m, " find-mask forwards recursions: %11u\n",
184 debug_atomic_read(&nr_find_usage_forwards_recursions));
185 seq_printf(m, " find-mask backwards checks: %11u\n",
186 debug_atomic_read(&nr_find_usage_backwards_checks));
187 seq_printf(m, " find-mask backwards recursions:%11u\n",
188 debug_atomic_read(&nr_find_usage_backwards_recursions));
189
190 seq_printf(m, " hardirq on events: %11u\n", hi1);
191 seq_printf(m, " hardirq off events: %11u\n", hi2);
192 seq_printf(m, " redundant hardirq ons: %11u\n", hr1);
193 seq_printf(m, " redundant hardirq offs: %11u\n", hr2);
194 seq_printf(m, " softirq on events: %11u\n", si1);
195 seq_printf(m, " softirq off events: %11u\n", si2);
196 seq_printf(m, " redundant softirq ons: %11u\n", sr1);
197 seq_printf(m, " redundant softirq offs: %11u\n", sr2);
198#endif
199}
200
201static int lockdep_stats_show(struct seq_file *m, void *v)
202{
203 struct lock_class *class;
204 unsigned long nr_unused = 0, nr_uncategorized = 0,
205 nr_irq_safe = 0, nr_irq_unsafe = 0,
206 nr_softirq_safe = 0, nr_softirq_unsafe = 0,
207 nr_hardirq_safe = 0, nr_hardirq_unsafe = 0,
208 nr_irq_read_safe = 0, nr_irq_read_unsafe = 0,
209 nr_softirq_read_safe = 0, nr_softirq_read_unsafe = 0,
210 nr_hardirq_read_safe = 0, nr_hardirq_read_unsafe = 0,
211 sum_forward_deps = 0, factor = 0;
212
213 list_for_each_entry(class, &all_lock_classes, lock_entry) {
214
215 if (class->usage_mask == 0)
216 nr_unused++;
217 if (class->usage_mask == LOCKF_USED)
218 nr_uncategorized++;
219 if (class->usage_mask & LOCKF_USED_IN_IRQ)
220 nr_irq_safe++;
221 if (class->usage_mask & LOCKF_ENABLED_IRQS)
222 nr_irq_unsafe++;
223 if (class->usage_mask & LOCKF_USED_IN_SOFTIRQ)
224 nr_softirq_safe++;
225 if (class->usage_mask & LOCKF_ENABLED_SOFTIRQS)
226 nr_softirq_unsafe++;
227 if (class->usage_mask & LOCKF_USED_IN_HARDIRQ)
228 nr_hardirq_safe++;
229 if (class->usage_mask & LOCKF_ENABLED_HARDIRQS)
230 nr_hardirq_unsafe++;
231 if (class->usage_mask & LOCKF_USED_IN_IRQ_READ)
232 nr_irq_read_safe++;
233 if (class->usage_mask & LOCKF_ENABLED_IRQS_READ)
234 nr_irq_read_unsafe++;
235 if (class->usage_mask & LOCKF_USED_IN_SOFTIRQ_READ)
236 nr_softirq_read_safe++;
237 if (class->usage_mask & LOCKF_ENABLED_SOFTIRQS_READ)
238 nr_softirq_read_unsafe++;
239 if (class->usage_mask & LOCKF_USED_IN_HARDIRQ_READ)
240 nr_hardirq_read_safe++;
241 if (class->usage_mask & LOCKF_ENABLED_HARDIRQS_READ)
242 nr_hardirq_read_unsafe++;
243
244 sum_forward_deps += count_forward_deps(class);
245 }
246#ifdef CONFIG_DEBUG_LOCKDEP
247 DEBUG_LOCKS_WARN_ON(debug_atomic_read(&nr_unused_locks) != nr_unused);
248#endif
249 seq_printf(m, " lock-classes: %11lu [max: %lu]\n",
250 nr_lock_classes, MAX_LOCKDEP_KEYS);
251 seq_printf(m, " direct dependencies: %11lu [max: %lu]\n",
252 nr_list_entries, MAX_LOCKDEP_ENTRIES);
253 seq_printf(m, " indirect dependencies: %11lu\n",
254 sum_forward_deps);
255
256 /*
257 * Total number of dependencies:
258 *
259 * All irq-safe locks may nest inside irq-unsafe locks,
260 * plus all the other known dependencies:
261 */
262 seq_printf(m, " all direct dependencies: %11lu\n",
263 nr_irq_unsafe * nr_irq_safe +
264 nr_hardirq_unsafe * nr_hardirq_safe +
265 nr_list_entries);
266
267 /*
268 * Estimated factor between direct and indirect
269 * dependencies:
270 */
271 if (nr_list_entries)
272 factor = sum_forward_deps / nr_list_entries;
273
274 seq_printf(m, " dependency chains: %11lu [max: %lu]\n",
275 nr_lock_chains, MAX_LOCKDEP_CHAINS);
276
277#ifdef CONFIG_TRACE_IRQFLAGS
278 seq_printf(m, " in-hardirq chains: %11u\n",
279 nr_hardirq_chains);
280 seq_printf(m, " in-softirq chains: %11u\n",
281 nr_softirq_chains);
282#endif
283 seq_printf(m, " in-process chains: %11u\n",
284 nr_process_chains);
285 seq_printf(m, " stack-trace entries: %11lu [max: %lu]\n",
286 nr_stack_trace_entries, MAX_STACK_TRACE_ENTRIES);
287 seq_printf(m, " combined max dependencies: %11u\n",
288 (nr_hardirq_chains + 1) *
289 (nr_softirq_chains + 1) *
290 (nr_process_chains + 1)
291 );
292 seq_printf(m, " hardirq-safe locks: %11lu\n",
293 nr_hardirq_safe);
294 seq_printf(m, " hardirq-unsafe locks: %11lu\n",
295 nr_hardirq_unsafe);
296 seq_printf(m, " softirq-safe locks: %11lu\n",
297 nr_softirq_safe);
298 seq_printf(m, " softirq-unsafe locks: %11lu\n",
299 nr_softirq_unsafe);
300 seq_printf(m, " irq-safe locks: %11lu\n",
301 nr_irq_safe);
302 seq_printf(m, " irq-unsafe locks: %11lu\n",
303 nr_irq_unsafe);
304
305 seq_printf(m, " hardirq-read-safe locks: %11lu\n",
306 nr_hardirq_read_safe);
307 seq_printf(m, " hardirq-read-unsafe locks: %11lu\n",
308 nr_hardirq_read_unsafe);
309 seq_printf(m, " softirq-read-safe locks: %11lu\n",
310 nr_softirq_read_safe);
311 seq_printf(m, " softirq-read-unsafe locks: %11lu\n",
312 nr_softirq_read_unsafe);
313 seq_printf(m, " irq-read-safe locks: %11lu\n",
314 nr_irq_read_safe);
315 seq_printf(m, " irq-read-unsafe locks: %11lu\n",
316 nr_irq_read_unsafe);
317
318 seq_printf(m, " uncategorized locks: %11lu\n",
319 nr_uncategorized);
320 seq_printf(m, " unused locks: %11lu\n",
321 nr_unused);
322 seq_printf(m, " max locking depth: %11u\n",
323 max_lockdep_depth);
324 seq_printf(m, " max recursion depth: %11u\n",
325 max_recursion_depth);
326 lockdep_stats_debug_show(m);
327 seq_printf(m, " debug_locks: %11u\n",
328 debug_locks);
329
330 return 0;
331}
332
333static int lockdep_stats_open(struct inode *inode, struct file *file)
334{
335 return single_open(file, lockdep_stats_show, NULL);
336}
337
338static const struct file_operations proc_lockdep_stats_operations = {
339 .open = lockdep_stats_open,
340 .read = seq_read,
341 .llseek = seq_lseek,
342 .release = seq_release,
343};
344
345static int __init lockdep_proc_init(void)
346{
347 struct proc_dir_entry *entry;
348
349 entry = create_proc_entry("lockdep", S_IRUSR, NULL);
350 if (entry)
351 entry->proc_fops = &proc_lockdep_operations;
352
353 entry = create_proc_entry("lockdep_stats", S_IRUSR, NULL);
354 if (entry)
355 entry->proc_fops = &proc_lockdep_stats_operations;
356
357 return 0;
358}
359
360__initcall(lockdep_proc_init);
361