[PATCH] Flush MMIO writes in reset sequence
[linux-2.6.git] / kernel / lockdep_proc.c
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 <mingo@redhat.com>
9  *
10  * Code for /proc/lockdep and /proc/lockdep_stats:
11  *
12  */
13 #include <linux/sched.h>
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>
19
20 #include "lockdep_internals.h"
21
22 static void *l_next(struct seq_file *m, void *v, loff_t *pos)
23 {
24         struct lock_class *class = v;
25
26         (*pos)++;
27
28         if (class->lock_entry.next != &all_lock_classes)
29                 class = list_entry(class->lock_entry.next, struct lock_class,
30                                   lock_entry);
31         else
32                 class = NULL;
33         m->private = class;
34
35         return class;
36 }
37
38 static void *l_start(struct seq_file *m, loff_t *pos)
39 {
40         struct lock_class *class = m->private;
41
42         if (&class->lock_entry == all_lock_classes.next)
43                 seq_printf(m, "all lock classes:\n");
44
45         return class;
46 }
47
48 static void l_stop(struct seq_file *m, void *v)
49 {
50 }
51
52 static unsigned long count_forward_deps(struct lock_class *class)
53 {
54         struct lock_list *entry;
55         unsigned long ret = 1;
56
57         /*
58          * Recurse this class's dependency list:
59          */
60         list_for_each_entry(entry, &class->locks_after, entry)
61                 ret += count_forward_deps(entry->class);
62
63         return ret;
64 }
65
66 static unsigned long count_backward_deps(struct lock_class *class)
67 {
68         struct lock_list *entry;
69         unsigned long ret = 1;
70
71         /*
72          * Recurse this class's dependency list:
73          */
74         list_for_each_entry(entry, &class->locks_before, entry)
75                 ret += count_backward_deps(entry->class);
76
77         return ret;
78 }
79
80 static int l_show(struct seq_file *m, void *v)
81 {
82         unsigned long nr_forward_deps, nr_backward_deps;
83         struct lock_class *class = m->private;
84         char str[128], c1, c2, c3, c4;
85         const char *name;
86
87         seq_printf(m, "%p", class->key);
88 #ifdef CONFIG_DEBUG_LOCKDEP
89         seq_printf(m, " OPS:%8ld", class->ops);
90 #endif
91         nr_forward_deps = count_forward_deps(class);
92         seq_printf(m, " FD:%5ld", nr_forward_deps);
93
94         nr_backward_deps = count_backward_deps(class);
95         seq_printf(m, " BD:%5ld", nr_backward_deps);
96
97         get_usage_chars(class, &c1, &c2, &c3, &c4);
98         seq_printf(m, " %c%c%c%c", c1, c2, c3, c4);
99
100         name = class->name;
101         if (!name) {
102                 name = __get_key_name(class->key, str);
103                 seq_printf(m, ": %s", name);
104         } else{
105                 seq_printf(m, ": %s", name);
106                 if (class->name_version > 1)
107                         seq_printf(m, "#%d", class->name_version);
108                 if (class->subclass)
109                         seq_printf(m, "/%d", class->subclass);
110         }
111         seq_puts(m, "\n");
112
113         return 0;
114 }
115
116 static struct seq_operations lockdep_ops = {
117         .start  = l_start,
118         .next   = l_next,
119         .stop   = l_stop,
120         .show   = l_show,
121 };
122
123 static int lockdep_open(struct inode *inode, struct file *file)
124 {
125         int res = seq_open(file, &lockdep_ops);
126         if (!res) {
127                 struct seq_file *m = file->private_data;
128
129                 if (!list_empty(&all_lock_classes))
130                         m->private = list_entry(all_lock_classes.next,
131                                         struct lock_class, lock_entry);
132                 else
133                         m->private = NULL;
134         }
135         return res;
136 }
137
138 static struct file_operations proc_lockdep_operations = {
139         .open           = lockdep_open,
140         .read           = seq_read,
141         .llseek         = seq_lseek,
142         .release        = seq_release,
143 };
144
145 static void lockdep_stats_debug_show(struct seq_file *m)
146 {
147 #ifdef CONFIG_DEBUG_LOCKDEP
148         unsigned int hi1 = debug_atomic_read(&hardirqs_on_events),
149                      hi2 = debug_atomic_read(&hardirqs_off_events),
150                      hr1 = debug_atomic_read(&redundant_hardirqs_on),
151                      hr2 = debug_atomic_read(&redundant_hardirqs_off),
152                      si1 = debug_atomic_read(&softirqs_on_events),
153                      si2 = debug_atomic_read(&softirqs_off_events),
154                      sr1 = debug_atomic_read(&redundant_softirqs_on),
155                      sr2 = debug_atomic_read(&redundant_softirqs_off);
156
157         seq_printf(m, " chain lookup misses:           %11u\n",
158                 debug_atomic_read(&chain_lookup_misses));
159         seq_printf(m, " chain lookup hits:             %11u\n",
160                 debug_atomic_read(&chain_lookup_hits));
161         seq_printf(m, " cyclic checks:                 %11u\n",
162                 debug_atomic_read(&nr_cyclic_checks));
163         seq_printf(m, " cyclic-check recursions:       %11u\n",
164                 debug_atomic_read(&nr_cyclic_check_recursions));
165         seq_printf(m, " find-mask forwards checks:     %11u\n",
166                 debug_atomic_read(&nr_find_usage_forwards_checks));
167         seq_printf(m, " find-mask forwards recursions: %11u\n",
168                 debug_atomic_read(&nr_find_usage_forwards_recursions));
169         seq_printf(m, " find-mask backwards checks:    %11u\n",
170                 debug_atomic_read(&nr_find_usage_backwards_checks));
171         seq_printf(m, " find-mask backwards recursions:%11u\n",
172                 debug_atomic_read(&nr_find_usage_backwards_recursions));
173
174         seq_printf(m, " hardirq on events:             %11u\n", hi1);
175         seq_printf(m, " hardirq off events:            %11u\n", hi2);
176         seq_printf(m, " redundant hardirq ons:         %11u\n", hr1);
177         seq_printf(m, " redundant hardirq offs:        %11u\n", hr2);
178         seq_printf(m, " softirq on events:             %11u\n", si1);
179         seq_printf(m, " softirq off events:            %11u\n", si2);
180         seq_printf(m, " redundant softirq ons:         %11u\n", sr1);
181         seq_printf(m, " redundant softirq offs:        %11u\n", sr2);
182 #endif
183 }
184
185 static int lockdep_stats_show(struct seq_file *m, void *v)
186 {
187         struct lock_class *class;
188         unsigned long nr_unused = 0, nr_uncategorized = 0,
189                       nr_irq_safe = 0, nr_irq_unsafe = 0,
190                       nr_softirq_safe = 0, nr_softirq_unsafe = 0,
191                       nr_hardirq_safe = 0, nr_hardirq_unsafe = 0,
192                       nr_irq_read_safe = 0, nr_irq_read_unsafe = 0,
193                       nr_softirq_read_safe = 0, nr_softirq_read_unsafe = 0,
194                       nr_hardirq_read_safe = 0, nr_hardirq_read_unsafe = 0,
195                       sum_forward_deps = 0, factor = 0;
196
197         list_for_each_entry(class, &all_lock_classes, lock_entry) {
198
199                 if (class->usage_mask == 0)
200                         nr_unused++;
201                 if (class->usage_mask == LOCKF_USED)
202                         nr_uncategorized++;
203                 if (class->usage_mask & LOCKF_USED_IN_IRQ)
204                         nr_irq_safe++;
205                 if (class->usage_mask & LOCKF_ENABLED_IRQS)
206                         nr_irq_unsafe++;
207                 if (class->usage_mask & LOCKF_USED_IN_SOFTIRQ)
208                         nr_softirq_safe++;
209                 if (class->usage_mask & LOCKF_ENABLED_SOFTIRQS)
210                         nr_softirq_unsafe++;
211                 if (class->usage_mask & LOCKF_USED_IN_HARDIRQ)
212                         nr_hardirq_safe++;
213                 if (class->usage_mask & LOCKF_ENABLED_HARDIRQS)
214                         nr_hardirq_unsafe++;
215                 if (class->usage_mask & LOCKF_USED_IN_IRQ_READ)
216                         nr_irq_read_safe++;
217                 if (class->usage_mask & LOCKF_ENABLED_IRQS_READ)
218                         nr_irq_read_unsafe++;
219                 if (class->usage_mask & LOCKF_USED_IN_SOFTIRQ_READ)
220                         nr_softirq_read_safe++;
221                 if (class->usage_mask & LOCKF_ENABLED_SOFTIRQS_READ)
222                         nr_softirq_read_unsafe++;
223                 if (class->usage_mask & LOCKF_USED_IN_HARDIRQ_READ)
224                         nr_hardirq_read_safe++;
225                 if (class->usage_mask & LOCKF_ENABLED_HARDIRQS_READ)
226                         nr_hardirq_read_unsafe++;
227
228                 sum_forward_deps += count_forward_deps(class);
229         }
230 #ifdef CONFIG_LOCKDEP_DEBUG
231         DEBUG_LOCKS_WARN_ON(debug_atomic_read(&nr_unused_locks) != nr_unused);
232 #endif
233         seq_printf(m, " lock-classes:                  %11lu [max: %lu]\n",
234                         nr_lock_classes, MAX_LOCKDEP_KEYS);
235         seq_printf(m, " direct dependencies:           %11lu [max: %lu]\n",
236                         nr_list_entries, MAX_LOCKDEP_ENTRIES);
237         seq_printf(m, " indirect dependencies:         %11lu\n",
238                         sum_forward_deps);
239
240         /*
241          * Total number of dependencies:
242          *
243          * All irq-safe locks may nest inside irq-unsafe locks,
244          * plus all the other known dependencies:
245          */
246         seq_printf(m, " all direct dependencies:       %11lu\n",
247                         nr_irq_unsafe * nr_irq_safe +
248                         nr_hardirq_unsafe * nr_hardirq_safe +
249                         nr_list_entries);
250
251         /*
252          * Estimated factor between direct and indirect
253          * dependencies:
254          */
255         if (nr_list_entries)
256                 factor = sum_forward_deps / nr_list_entries;
257
258         seq_printf(m, " dependency chains:             %11lu [max: %lu]\n",
259                         nr_lock_chains, MAX_LOCKDEP_CHAINS);
260
261 #ifdef CONFIG_TRACE_IRQFLAGS
262         seq_printf(m, " in-hardirq chains:             %11u\n",
263                         nr_hardirq_chains);
264         seq_printf(m, " in-softirq chains:             %11u\n",
265                         nr_softirq_chains);
266 #endif
267         seq_printf(m, " in-process chains:             %11u\n",
268                         nr_process_chains);
269         seq_printf(m, " stack-trace entries:           %11lu [max: %lu]\n",
270                         nr_stack_trace_entries, MAX_STACK_TRACE_ENTRIES);
271         seq_printf(m, " combined max dependencies:     %11u\n",
272                         (nr_hardirq_chains + 1) *
273                         (nr_softirq_chains + 1) *
274                         (nr_process_chains + 1)
275         );
276         seq_printf(m, " hardirq-safe locks:            %11lu\n",
277                         nr_hardirq_safe);
278         seq_printf(m, " hardirq-unsafe locks:          %11lu\n",
279                         nr_hardirq_unsafe);
280         seq_printf(m, " softirq-safe locks:            %11lu\n",
281                         nr_softirq_safe);
282         seq_printf(m, " softirq-unsafe locks:          %11lu\n",
283                         nr_softirq_unsafe);
284         seq_printf(m, " irq-safe locks:                %11lu\n",
285                         nr_irq_safe);
286         seq_printf(m, " irq-unsafe locks:              %11lu\n",
287                         nr_irq_unsafe);
288
289         seq_printf(m, " hardirq-read-safe locks:       %11lu\n",
290                         nr_hardirq_read_safe);
291         seq_printf(m, " hardirq-read-unsafe locks:     %11lu\n",
292                         nr_hardirq_read_unsafe);
293         seq_printf(m, " softirq-read-safe locks:       %11lu\n",
294                         nr_softirq_read_safe);
295         seq_printf(m, " softirq-read-unsafe locks:     %11lu\n",
296                         nr_softirq_read_unsafe);
297         seq_printf(m, " irq-read-safe locks:           %11lu\n",
298                         nr_irq_read_safe);
299         seq_printf(m, " irq-read-unsafe locks:         %11lu\n",
300                         nr_irq_read_unsafe);
301
302         seq_printf(m, " uncategorized locks:           %11lu\n",
303                         nr_uncategorized);
304         seq_printf(m, " unused locks:                  %11lu\n",
305                         nr_unused);
306         seq_printf(m, " max locking depth:             %11u\n",
307                         max_lockdep_depth);
308         seq_printf(m, " max recursion depth:           %11u\n",
309                         max_recursion_depth);
310         lockdep_stats_debug_show(m);
311         seq_printf(m, " debug_locks:                   %11u\n",
312                         debug_locks);
313
314         return 0;
315 }
316
317 static int lockdep_stats_open(struct inode *inode, struct file *file)
318 {
319         return single_open(file, lockdep_stats_show, NULL);
320 }
321
322 static struct file_operations proc_lockdep_stats_operations = {
323         .open           = lockdep_stats_open,
324         .read           = seq_read,
325         .llseek         = seq_lseek,
326         .release        = seq_release,
327 };
328
329 static int __init lockdep_proc_init(void)
330 {
331         struct proc_dir_entry *entry;
332
333         entry = create_proc_entry("lockdep", S_IRUSR, NULL);
334         if (entry)
335                 entry->proc_fops = &proc_lockdep_operations;
336
337         entry = create_proc_entry("lockdep_stats", S_IRUSR, NULL);
338         if (entry)
339                 entry->proc_fops = &proc_lockdep_stats_operations;
340
341         return 0;
342 }
343
344 __initcall(lockdep_proc_init);
345