Commit | Line | Data |
---|---|---|
3ac7fe5a TG |
1 | /* |
2 | * Generic infrastructure for lifetime debugging of objects. | |
3 | * | |
4 | * Started by Thomas Gleixner | |
5 | * | |
6 | * Copyright (C) 2008, Thomas Gleixner <tglx@linutronix.de> | |
7 | * | |
8 | * For licencing details see kernel-base/COPYING | |
9 | */ | |
10 | #include <linux/debugobjects.h> | |
11 | #include <linux/interrupt.h> | |
d43c36dc | 12 | #include <linux/sched.h> |
3ac7fe5a TG |
13 | #include <linux/seq_file.h> |
14 | #include <linux/debugfs.h> | |
15 | #include <linux/hash.h> | |
16 | ||
17 | #define ODEBUG_HASH_BITS 14 | |
18 | #define ODEBUG_HASH_SIZE (1 << ODEBUG_HASH_BITS) | |
19 | ||
20 | #define ODEBUG_POOL_SIZE 512 | |
21 | #define ODEBUG_POOL_MIN_LEVEL 256 | |
22 | ||
23 | #define ODEBUG_CHUNK_SHIFT PAGE_SHIFT | |
24 | #define ODEBUG_CHUNK_SIZE (1 << ODEBUG_CHUNK_SHIFT) | |
25 | #define ODEBUG_CHUNK_MASK (~(ODEBUG_CHUNK_SIZE - 1)) | |
26 | ||
27 | struct debug_bucket { | |
28 | struct hlist_head list; | |
aef9cb05 | 29 | raw_spinlock_t lock; |
3ac7fe5a TG |
30 | }; |
31 | ||
32 | static struct debug_bucket obj_hash[ODEBUG_HASH_SIZE]; | |
33 | ||
1be1cb7b | 34 | static struct debug_obj obj_static_pool[ODEBUG_POOL_SIZE] __initdata; |
3ac7fe5a | 35 | |
aef9cb05 | 36 | static DEFINE_RAW_SPINLOCK(pool_lock); |
3ac7fe5a TG |
37 | |
38 | static HLIST_HEAD(obj_pool); | |
39 | ||
40 | static int obj_pool_min_free = ODEBUG_POOL_SIZE; | |
41 | static int obj_pool_free = ODEBUG_POOL_SIZE; | |
42 | static int obj_pool_used; | |
43 | static int obj_pool_max_used; | |
44 | static struct kmem_cache *obj_cache; | |
45 | ||
46 | static int debug_objects_maxchain __read_mostly; | |
47 | static int debug_objects_fixups __read_mostly; | |
48 | static int debug_objects_warnings __read_mostly; | |
3ae70205 IM |
49 | static int debug_objects_enabled __read_mostly |
50 | = CONFIG_DEBUG_OBJECTS_ENABLE_DEFAULT; | |
51 | ||
3ac7fe5a TG |
52 | static struct debug_obj_descr *descr_test __read_mostly; |
53 | ||
337fff8b TG |
54 | static void free_obj_work(struct work_struct *work); |
55 | static DECLARE_WORK(debug_obj_work, free_obj_work); | |
56 | ||
3ac7fe5a TG |
57 | static int __init enable_object_debug(char *str) |
58 | { | |
59 | debug_objects_enabled = 1; | |
60 | return 0; | |
61 | } | |
3e8ebb5c KM |
62 | |
63 | static int __init disable_object_debug(char *str) | |
64 | { | |
65 | debug_objects_enabled = 0; | |
66 | return 0; | |
67 | } | |
68 | ||
3ac7fe5a | 69 | early_param("debug_objects", enable_object_debug); |
3e8ebb5c | 70 | early_param("no_debug_objects", disable_object_debug); |
3ac7fe5a TG |
71 | |
72 | static const char *obj_states[ODEBUG_STATE_MAX] = { | |
73 | [ODEBUG_STATE_NONE] = "none", | |
74 | [ODEBUG_STATE_INIT] = "initialized", | |
75 | [ODEBUG_STATE_INACTIVE] = "inactive", | |
76 | [ODEBUG_STATE_ACTIVE] = "active", | |
77 | [ODEBUG_STATE_DESTROYED] = "destroyed", | |
78 | [ODEBUG_STATE_NOTAVAILABLE] = "not available", | |
79 | }; | |
80 | ||
81 | static int fill_pool(void) | |
82 | { | |
83 | gfp_t gfp = GFP_ATOMIC | __GFP_NORETRY | __GFP_NOWARN; | |
84 | struct debug_obj *new; | |
50db04dd | 85 | unsigned long flags; |
3ac7fe5a TG |
86 | |
87 | if (likely(obj_pool_free >= ODEBUG_POOL_MIN_LEVEL)) | |
88 | return obj_pool_free; | |
89 | ||
90 | if (unlikely(!obj_cache)) | |
91 | return obj_pool_free; | |
92 | ||
93 | while (obj_pool_free < ODEBUG_POOL_MIN_LEVEL) { | |
94 | ||
95 | new = kmem_cache_zalloc(obj_cache, gfp); | |
96 | if (!new) | |
97 | return obj_pool_free; | |
98 | ||
aef9cb05 | 99 | raw_spin_lock_irqsave(&pool_lock, flags); |
3ac7fe5a TG |
100 | hlist_add_head(&new->node, &obj_pool); |
101 | obj_pool_free++; | |
aef9cb05 | 102 | raw_spin_unlock_irqrestore(&pool_lock, flags); |
3ac7fe5a TG |
103 | } |
104 | return obj_pool_free; | |
105 | } | |
106 | ||
107 | /* | |
108 | * Lookup an object in the hash bucket. | |
109 | */ | |
110 | static struct debug_obj *lookup_object(void *addr, struct debug_bucket *b) | |
111 | { | |
112 | struct hlist_node *node; | |
113 | struct debug_obj *obj; | |
114 | int cnt = 0; | |
115 | ||
116 | hlist_for_each_entry(obj, node, &b->list, node) { | |
117 | cnt++; | |
118 | if (obj->object == addr) | |
119 | return obj; | |
120 | } | |
121 | if (cnt > debug_objects_maxchain) | |
122 | debug_objects_maxchain = cnt; | |
123 | ||
124 | return NULL; | |
125 | } | |
126 | ||
127 | /* | |
50db04dd | 128 | * Allocate a new object. If the pool is empty, switch off the debugger. |
673d62cc | 129 | * Must be called with interrupts disabled. |
3ac7fe5a TG |
130 | */ |
131 | static struct debug_obj * | |
132 | alloc_object(void *addr, struct debug_bucket *b, struct debug_obj_descr *descr) | |
133 | { | |
134 | struct debug_obj *obj = NULL; | |
3ac7fe5a | 135 | |
aef9cb05 | 136 | raw_spin_lock(&pool_lock); |
3ac7fe5a TG |
137 | if (obj_pool.first) { |
138 | obj = hlist_entry(obj_pool.first, typeof(*obj), node); | |
139 | ||
140 | obj->object = addr; | |
141 | obj->descr = descr; | |
142 | obj->state = ODEBUG_STATE_NONE; | |
143 | hlist_del(&obj->node); | |
144 | ||
145 | hlist_add_head(&obj->node, &b->list); | |
146 | ||
147 | obj_pool_used++; | |
148 | if (obj_pool_used > obj_pool_max_used) | |
149 | obj_pool_max_used = obj_pool_used; | |
150 | ||
151 | obj_pool_free--; | |
152 | if (obj_pool_free < obj_pool_min_free) | |
153 | obj_pool_min_free = obj_pool_free; | |
154 | } | |
aef9cb05 | 155 | raw_spin_unlock(&pool_lock); |
3ac7fe5a | 156 | |
3ac7fe5a TG |
157 | return obj; |
158 | } | |
159 | ||
160 | /* | |
337fff8b | 161 | * workqueue function to free objects. |
3ac7fe5a | 162 | */ |
337fff8b | 163 | static void free_obj_work(struct work_struct *work) |
3ac7fe5a | 164 | { |
337fff8b | 165 | struct debug_obj *obj; |
673d62cc | 166 | unsigned long flags; |
3ac7fe5a | 167 | |
aef9cb05 | 168 | raw_spin_lock_irqsave(&pool_lock, flags); |
337fff8b TG |
169 | while (obj_pool_free > ODEBUG_POOL_SIZE) { |
170 | obj = hlist_entry(obj_pool.first, typeof(*obj), node); | |
171 | hlist_del(&obj->node); | |
172 | obj_pool_free--; | |
173 | /* | |
174 | * We release pool_lock across kmem_cache_free() to | |
175 | * avoid contention on pool_lock. | |
176 | */ | |
aef9cb05 | 177 | raw_spin_unlock_irqrestore(&pool_lock, flags); |
3ac7fe5a | 178 | kmem_cache_free(obj_cache, obj); |
aef9cb05 | 179 | raw_spin_lock_irqsave(&pool_lock, flags); |
3ac7fe5a | 180 | } |
aef9cb05 | 181 | raw_spin_unlock_irqrestore(&pool_lock, flags); |
337fff8b TG |
182 | } |
183 | ||
184 | /* | |
185 | * Put the object back into the pool and schedule work to free objects | |
186 | * if necessary. | |
187 | */ | |
188 | static void free_object(struct debug_obj *obj) | |
189 | { | |
190 | unsigned long flags; | |
191 | int sched = 0; | |
192 | ||
aef9cb05 | 193 | raw_spin_lock_irqsave(&pool_lock, flags); |
337fff8b TG |
194 | /* |
195 | * schedule work when the pool is filled and the cache is | |
196 | * initialized: | |
197 | */ | |
198 | if (obj_pool_free > ODEBUG_POOL_SIZE && obj_cache) | |
199 | sched = !work_pending(&debug_obj_work); | |
200 | hlist_add_head(&obj->node, &obj_pool); | |
201 | obj_pool_free++; | |
202 | obj_pool_used--; | |
aef9cb05 | 203 | raw_spin_unlock_irqrestore(&pool_lock, flags); |
337fff8b TG |
204 | if (sched) |
205 | schedule_work(&debug_obj_work); | |
3ac7fe5a TG |
206 | } |
207 | ||
208 | /* | |
209 | * We run out of memory. That means we probably have tons of objects | |
210 | * allocated. | |
211 | */ | |
212 | static void debug_objects_oom(void) | |
213 | { | |
214 | struct debug_bucket *db = obj_hash; | |
215 | struct hlist_node *node, *tmp; | |
673d62cc | 216 | HLIST_HEAD(freelist); |
3ac7fe5a TG |
217 | struct debug_obj *obj; |
218 | unsigned long flags; | |
219 | int i; | |
220 | ||
221 | printk(KERN_WARNING "ODEBUG: Out of memory. ODEBUG disabled\n"); | |
222 | ||
223 | for (i = 0; i < ODEBUG_HASH_SIZE; i++, db++) { | |
aef9cb05 | 224 | raw_spin_lock_irqsave(&db->lock, flags); |
673d62cc | 225 | hlist_move_list(&db->list, &freelist); |
aef9cb05 | 226 | raw_spin_unlock_irqrestore(&db->lock, flags); |
673d62cc VN |
227 | |
228 | /* Now free them */ | |
229 | hlist_for_each_entry_safe(obj, node, tmp, &freelist, node) { | |
3ac7fe5a TG |
230 | hlist_del(&obj->node); |
231 | free_object(obj); | |
232 | } | |
3ac7fe5a TG |
233 | } |
234 | } | |
235 | ||
236 | /* | |
237 | * We use the pfn of the address for the hash. That way we can check | |
238 | * for freed objects simply by checking the affected bucket. | |
239 | */ | |
240 | static struct debug_bucket *get_bucket(unsigned long addr) | |
241 | { | |
242 | unsigned long hash; | |
243 | ||
244 | hash = hash_long((addr >> ODEBUG_CHUNK_SHIFT), ODEBUG_HASH_BITS); | |
245 | return &obj_hash[hash]; | |
246 | } | |
247 | ||
248 | static void debug_print_object(struct debug_obj *obj, char *msg) | |
249 | { | |
250 | static int limit; | |
251 | ||
252 | if (limit < 5 && obj->descr != descr_test) { | |
253 | limit++; | |
5cd2b459 | 254 | WARN(1, KERN_ERR "ODEBUG: %s %s object type: %s\n", msg, |
3ac7fe5a | 255 | obj_states[obj->state], obj->descr->name); |
3ac7fe5a TG |
256 | } |
257 | debug_objects_warnings++; | |
258 | } | |
259 | ||
260 | /* | |
261 | * Try to repair the damage, so we have a better chance to get useful | |
262 | * debug output. | |
263 | */ | |
264 | static void | |
265 | debug_object_fixup(int (*fixup)(void *addr, enum debug_obj_state state), | |
266 | void * addr, enum debug_obj_state state) | |
267 | { | |
268 | if (fixup) | |
269 | debug_objects_fixups += fixup(addr, state); | |
270 | } | |
271 | ||
272 | static void debug_object_is_on_stack(void *addr, int onstack) | |
273 | { | |
3ac7fe5a TG |
274 | int is_on_stack; |
275 | static int limit; | |
276 | ||
277 | if (limit > 4) | |
278 | return; | |
279 | ||
8b05c7e6 | 280 | is_on_stack = object_is_on_stack(addr); |
3ac7fe5a TG |
281 | if (is_on_stack == onstack) |
282 | return; | |
283 | ||
284 | limit++; | |
285 | if (is_on_stack) | |
286 | printk(KERN_WARNING | |
287 | "ODEBUG: object is on stack, but not annotated\n"); | |
288 | else | |
289 | printk(KERN_WARNING | |
290 | "ODEBUG: object is not on stack, but annotated\n"); | |
291 | WARN_ON(1); | |
292 | } | |
293 | ||
294 | static void | |
295 | __debug_object_init(void *addr, struct debug_obj_descr *descr, int onstack) | |
296 | { | |
297 | enum debug_obj_state state; | |
298 | struct debug_bucket *db; | |
299 | struct debug_obj *obj; | |
300 | unsigned long flags; | |
301 | ||
50db04dd VN |
302 | fill_pool(); |
303 | ||
3ac7fe5a TG |
304 | db = get_bucket((unsigned long) addr); |
305 | ||
aef9cb05 | 306 | raw_spin_lock_irqsave(&db->lock, flags); |
3ac7fe5a TG |
307 | |
308 | obj = lookup_object(addr, db); | |
309 | if (!obj) { | |
310 | obj = alloc_object(addr, db, descr); | |
311 | if (!obj) { | |
312 | debug_objects_enabled = 0; | |
aef9cb05 | 313 | raw_spin_unlock_irqrestore(&db->lock, flags); |
3ac7fe5a TG |
314 | debug_objects_oom(); |
315 | return; | |
316 | } | |
317 | debug_object_is_on_stack(addr, onstack); | |
318 | } | |
319 | ||
320 | switch (obj->state) { | |
321 | case ODEBUG_STATE_NONE: | |
322 | case ODEBUG_STATE_INIT: | |
323 | case ODEBUG_STATE_INACTIVE: | |
324 | obj->state = ODEBUG_STATE_INIT; | |
325 | break; | |
326 | ||
327 | case ODEBUG_STATE_ACTIVE: | |
328 | debug_print_object(obj, "init"); | |
329 | state = obj->state; | |
aef9cb05 | 330 | raw_spin_unlock_irqrestore(&db->lock, flags); |
3ac7fe5a TG |
331 | debug_object_fixup(descr->fixup_init, addr, state); |
332 | return; | |
333 | ||
334 | case ODEBUG_STATE_DESTROYED: | |
335 | debug_print_object(obj, "init"); | |
336 | break; | |
337 | default: | |
338 | break; | |
339 | } | |
340 | ||
aef9cb05 | 341 | raw_spin_unlock_irqrestore(&db->lock, flags); |
3ac7fe5a TG |
342 | } |
343 | ||
344 | /** | |
345 | * debug_object_init - debug checks when an object is initialized | |
346 | * @addr: address of the object | |
347 | * @descr: pointer to an object specific debug description structure | |
348 | */ | |
349 | void debug_object_init(void *addr, struct debug_obj_descr *descr) | |
350 | { | |
351 | if (!debug_objects_enabled) | |
352 | return; | |
353 | ||
354 | __debug_object_init(addr, descr, 0); | |
355 | } | |
356 | ||
357 | /** | |
358 | * debug_object_init_on_stack - debug checks when an object on stack is | |
359 | * initialized | |
360 | * @addr: address of the object | |
361 | * @descr: pointer to an object specific debug description structure | |
362 | */ | |
363 | void debug_object_init_on_stack(void *addr, struct debug_obj_descr *descr) | |
364 | { | |
365 | if (!debug_objects_enabled) | |
366 | return; | |
367 | ||
368 | __debug_object_init(addr, descr, 1); | |
369 | } | |
370 | ||
371 | /** | |
372 | * debug_object_activate - debug checks when an object is activated | |
373 | * @addr: address of the object | |
374 | * @descr: pointer to an object specific debug description structure | |
375 | */ | |
376 | void debug_object_activate(void *addr, struct debug_obj_descr *descr) | |
377 | { | |
378 | enum debug_obj_state state; | |
379 | struct debug_bucket *db; | |
380 | struct debug_obj *obj; | |
381 | unsigned long flags; | |
382 | ||
383 | if (!debug_objects_enabled) | |
384 | return; | |
385 | ||
386 | db = get_bucket((unsigned long) addr); | |
387 | ||
aef9cb05 | 388 | raw_spin_lock_irqsave(&db->lock, flags); |
3ac7fe5a TG |
389 | |
390 | obj = lookup_object(addr, db); | |
391 | if (obj) { | |
392 | switch (obj->state) { | |
393 | case ODEBUG_STATE_INIT: | |
394 | case ODEBUG_STATE_INACTIVE: | |
395 | obj->state = ODEBUG_STATE_ACTIVE; | |
396 | break; | |
397 | ||
398 | case ODEBUG_STATE_ACTIVE: | |
399 | debug_print_object(obj, "activate"); | |
400 | state = obj->state; | |
aef9cb05 | 401 | raw_spin_unlock_irqrestore(&db->lock, flags); |
3ac7fe5a TG |
402 | debug_object_fixup(descr->fixup_activate, addr, state); |
403 | return; | |
404 | ||
405 | case ODEBUG_STATE_DESTROYED: | |
406 | debug_print_object(obj, "activate"); | |
407 | break; | |
408 | default: | |
409 | break; | |
410 | } | |
aef9cb05 | 411 | raw_spin_unlock_irqrestore(&db->lock, flags); |
3ac7fe5a TG |
412 | return; |
413 | } | |
414 | ||
aef9cb05 | 415 | raw_spin_unlock_irqrestore(&db->lock, flags); |
3ac7fe5a TG |
416 | /* |
417 | * This happens when a static object is activated. We | |
418 | * let the type specific code decide whether this is | |
419 | * true or not. | |
420 | */ | |
421 | debug_object_fixup(descr->fixup_activate, addr, | |
422 | ODEBUG_STATE_NOTAVAILABLE); | |
423 | } | |
424 | ||
425 | /** | |
426 | * debug_object_deactivate - debug checks when an object is deactivated | |
427 | * @addr: address of the object | |
428 | * @descr: pointer to an object specific debug description structure | |
429 | */ | |
430 | void debug_object_deactivate(void *addr, struct debug_obj_descr *descr) | |
431 | { | |
432 | struct debug_bucket *db; | |
433 | struct debug_obj *obj; | |
434 | unsigned long flags; | |
435 | ||
436 | if (!debug_objects_enabled) | |
437 | return; | |
438 | ||
439 | db = get_bucket((unsigned long) addr); | |
440 | ||
aef9cb05 | 441 | raw_spin_lock_irqsave(&db->lock, flags); |
3ac7fe5a TG |
442 | |
443 | obj = lookup_object(addr, db); | |
444 | if (obj) { | |
445 | switch (obj->state) { | |
446 | case ODEBUG_STATE_INIT: | |
447 | case ODEBUG_STATE_INACTIVE: | |
448 | case ODEBUG_STATE_ACTIVE: | |
449 | obj->state = ODEBUG_STATE_INACTIVE; | |
450 | break; | |
451 | ||
452 | case ODEBUG_STATE_DESTROYED: | |
453 | debug_print_object(obj, "deactivate"); | |
454 | break; | |
455 | default: | |
456 | break; | |
457 | } | |
458 | } else { | |
459 | struct debug_obj o = { .object = addr, | |
460 | .state = ODEBUG_STATE_NOTAVAILABLE, | |
461 | .descr = descr }; | |
462 | ||
463 | debug_print_object(&o, "deactivate"); | |
464 | } | |
465 | ||
aef9cb05 | 466 | raw_spin_unlock_irqrestore(&db->lock, flags); |
3ac7fe5a TG |
467 | } |
468 | ||
469 | /** | |
470 | * debug_object_destroy - debug checks when an object is destroyed | |
471 | * @addr: address of the object | |
472 | * @descr: pointer to an object specific debug description structure | |
473 | */ | |
474 | void debug_object_destroy(void *addr, struct debug_obj_descr *descr) | |
475 | { | |
476 | enum debug_obj_state state; | |
477 | struct debug_bucket *db; | |
478 | struct debug_obj *obj; | |
479 | unsigned long flags; | |
480 | ||
481 | if (!debug_objects_enabled) | |
482 | return; | |
483 | ||
484 | db = get_bucket((unsigned long) addr); | |
485 | ||
aef9cb05 | 486 | raw_spin_lock_irqsave(&db->lock, flags); |
3ac7fe5a TG |
487 | |
488 | obj = lookup_object(addr, db); | |
489 | if (!obj) | |
490 | goto out_unlock; | |
491 | ||
492 | switch (obj->state) { | |
493 | case ODEBUG_STATE_NONE: | |
494 | case ODEBUG_STATE_INIT: | |
495 | case ODEBUG_STATE_INACTIVE: | |
496 | obj->state = ODEBUG_STATE_DESTROYED; | |
497 | break; | |
498 | case ODEBUG_STATE_ACTIVE: | |
499 | debug_print_object(obj, "destroy"); | |
500 | state = obj->state; | |
aef9cb05 | 501 | raw_spin_unlock_irqrestore(&db->lock, flags); |
3ac7fe5a TG |
502 | debug_object_fixup(descr->fixup_destroy, addr, state); |
503 | return; | |
504 | ||
505 | case ODEBUG_STATE_DESTROYED: | |
506 | debug_print_object(obj, "destroy"); | |
507 | break; | |
508 | default: | |
509 | break; | |
510 | } | |
511 | out_unlock: | |
aef9cb05 | 512 | raw_spin_unlock_irqrestore(&db->lock, flags); |
3ac7fe5a TG |
513 | } |
514 | ||
515 | /** | |
516 | * debug_object_free - debug checks when an object is freed | |
517 | * @addr: address of the object | |
518 | * @descr: pointer to an object specific debug description structure | |
519 | */ | |
520 | void debug_object_free(void *addr, struct debug_obj_descr *descr) | |
521 | { | |
522 | enum debug_obj_state state; | |
523 | struct debug_bucket *db; | |
524 | struct debug_obj *obj; | |
525 | unsigned long flags; | |
526 | ||
527 | if (!debug_objects_enabled) | |
528 | return; | |
529 | ||
530 | db = get_bucket((unsigned long) addr); | |
531 | ||
aef9cb05 | 532 | raw_spin_lock_irqsave(&db->lock, flags); |
3ac7fe5a TG |
533 | |
534 | obj = lookup_object(addr, db); | |
535 | if (!obj) | |
536 | goto out_unlock; | |
537 | ||
538 | switch (obj->state) { | |
539 | case ODEBUG_STATE_ACTIVE: | |
540 | debug_print_object(obj, "free"); | |
541 | state = obj->state; | |
aef9cb05 | 542 | raw_spin_unlock_irqrestore(&db->lock, flags); |
3ac7fe5a TG |
543 | debug_object_fixup(descr->fixup_free, addr, state); |
544 | return; | |
545 | default: | |
546 | hlist_del(&obj->node); | |
aef9cb05 | 547 | raw_spin_unlock_irqrestore(&db->lock, flags); |
3ac7fe5a | 548 | free_object(obj); |
673d62cc | 549 | return; |
3ac7fe5a TG |
550 | } |
551 | out_unlock: | |
aef9cb05 | 552 | raw_spin_unlock_irqrestore(&db->lock, flags); |
3ac7fe5a TG |
553 | } |
554 | ||
555 | #ifdef CONFIG_DEBUG_OBJECTS_FREE | |
556 | static void __debug_check_no_obj_freed(const void *address, unsigned long size) | |
557 | { | |
558 | unsigned long flags, oaddr, saddr, eaddr, paddr, chunks; | |
559 | struct hlist_node *node, *tmp; | |
673d62cc | 560 | HLIST_HEAD(freelist); |
3ac7fe5a TG |
561 | struct debug_obj_descr *descr; |
562 | enum debug_obj_state state; | |
563 | struct debug_bucket *db; | |
564 | struct debug_obj *obj; | |
565 | int cnt; | |
566 | ||
567 | saddr = (unsigned long) address; | |
568 | eaddr = saddr + size; | |
569 | paddr = saddr & ODEBUG_CHUNK_MASK; | |
570 | chunks = ((eaddr - paddr) + (ODEBUG_CHUNK_SIZE - 1)); | |
571 | chunks >>= ODEBUG_CHUNK_SHIFT; | |
572 | ||
573 | for (;chunks > 0; chunks--, paddr += ODEBUG_CHUNK_SIZE) { | |
574 | db = get_bucket(paddr); | |
575 | ||
576 | repeat: | |
577 | cnt = 0; | |
aef9cb05 | 578 | raw_spin_lock_irqsave(&db->lock, flags); |
3ac7fe5a TG |
579 | hlist_for_each_entry_safe(obj, node, tmp, &db->list, node) { |
580 | cnt++; | |
581 | oaddr = (unsigned long) obj->object; | |
582 | if (oaddr < saddr || oaddr >= eaddr) | |
583 | continue; | |
584 | ||
585 | switch (obj->state) { | |
586 | case ODEBUG_STATE_ACTIVE: | |
587 | debug_print_object(obj, "free"); | |
588 | descr = obj->descr; | |
589 | state = obj->state; | |
aef9cb05 | 590 | raw_spin_unlock_irqrestore(&db->lock, flags); |
3ac7fe5a TG |
591 | debug_object_fixup(descr->fixup_free, |
592 | (void *) oaddr, state); | |
593 | goto repeat; | |
594 | default: | |
595 | hlist_del(&obj->node); | |
673d62cc | 596 | hlist_add_head(&obj->node, &freelist); |
3ac7fe5a TG |
597 | break; |
598 | } | |
599 | } | |
aef9cb05 | 600 | raw_spin_unlock_irqrestore(&db->lock, flags); |
673d62cc VN |
601 | |
602 | /* Now free them */ | |
603 | hlist_for_each_entry_safe(obj, node, tmp, &freelist, node) { | |
604 | hlist_del(&obj->node); | |
605 | free_object(obj); | |
606 | } | |
607 | ||
3ac7fe5a TG |
608 | if (cnt > debug_objects_maxchain) |
609 | debug_objects_maxchain = cnt; | |
610 | } | |
611 | } | |
612 | ||
613 | void debug_check_no_obj_freed(const void *address, unsigned long size) | |
614 | { | |
615 | if (debug_objects_enabled) | |
616 | __debug_check_no_obj_freed(address, size); | |
617 | } | |
618 | #endif | |
619 | ||
620 | #ifdef CONFIG_DEBUG_FS | |
621 | ||
622 | static int debug_stats_show(struct seq_file *m, void *v) | |
623 | { | |
624 | seq_printf(m, "max_chain :%d\n", debug_objects_maxchain); | |
625 | seq_printf(m, "warnings :%d\n", debug_objects_warnings); | |
626 | seq_printf(m, "fixups :%d\n", debug_objects_fixups); | |
627 | seq_printf(m, "pool_free :%d\n", obj_pool_free); | |
628 | seq_printf(m, "pool_min_free :%d\n", obj_pool_min_free); | |
629 | seq_printf(m, "pool_used :%d\n", obj_pool_used); | |
630 | seq_printf(m, "pool_max_used :%d\n", obj_pool_max_used); | |
631 | return 0; | |
632 | } | |
633 | ||
634 | static int debug_stats_open(struct inode *inode, struct file *filp) | |
635 | { | |
636 | return single_open(filp, debug_stats_show, NULL); | |
637 | } | |
638 | ||
639 | static const struct file_operations debug_stats_fops = { | |
640 | .open = debug_stats_open, | |
641 | .read = seq_read, | |
642 | .llseek = seq_lseek, | |
643 | .release = single_release, | |
644 | }; | |
645 | ||
646 | static int __init debug_objects_init_debugfs(void) | |
647 | { | |
648 | struct dentry *dbgdir, *dbgstats; | |
649 | ||
650 | if (!debug_objects_enabled) | |
651 | return 0; | |
652 | ||
653 | dbgdir = debugfs_create_dir("debug_objects", NULL); | |
654 | if (!dbgdir) | |
655 | return -ENOMEM; | |
656 | ||
657 | dbgstats = debugfs_create_file("stats", 0444, dbgdir, NULL, | |
658 | &debug_stats_fops); | |
659 | if (!dbgstats) | |
660 | goto err; | |
661 | ||
662 | return 0; | |
663 | ||
664 | err: | |
665 | debugfs_remove(dbgdir); | |
666 | ||
667 | return -ENOMEM; | |
668 | } | |
669 | __initcall(debug_objects_init_debugfs); | |
670 | ||
671 | #else | |
672 | static inline void debug_objects_init_debugfs(void) { } | |
673 | #endif | |
674 | ||
675 | #ifdef CONFIG_DEBUG_OBJECTS_SELFTEST | |
676 | ||
677 | /* Random data structure for the self test */ | |
678 | struct self_test { | |
679 | unsigned long dummy1[6]; | |
680 | int static_init; | |
681 | unsigned long dummy2[3]; | |
682 | }; | |
683 | ||
684 | static __initdata struct debug_obj_descr descr_type_test; | |
685 | ||
686 | /* | |
687 | * fixup_init is called when: | |
688 | * - an active object is initialized | |
689 | */ | |
690 | static int __init fixup_init(void *addr, enum debug_obj_state state) | |
691 | { | |
692 | struct self_test *obj = addr; | |
693 | ||
694 | switch (state) { | |
695 | case ODEBUG_STATE_ACTIVE: | |
696 | debug_object_deactivate(obj, &descr_type_test); | |
697 | debug_object_init(obj, &descr_type_test); | |
698 | return 1; | |
699 | default: | |
700 | return 0; | |
701 | } | |
702 | } | |
703 | ||
704 | /* | |
705 | * fixup_activate is called when: | |
706 | * - an active object is activated | |
707 | * - an unknown object is activated (might be a statically initialized object) | |
708 | */ | |
709 | static int __init fixup_activate(void *addr, enum debug_obj_state state) | |
710 | { | |
711 | struct self_test *obj = addr; | |
712 | ||
713 | switch (state) { | |
714 | case ODEBUG_STATE_NOTAVAILABLE: | |
715 | if (obj->static_init == 1) { | |
716 | debug_object_init(obj, &descr_type_test); | |
717 | debug_object_activate(obj, &descr_type_test); | |
718 | /* | |
719 | * Real code should return 0 here ! This is | |
720 | * not a fixup of some bad behaviour. We | |
721 | * merily call the debug_init function to keep | |
722 | * track of the object. | |
723 | */ | |
724 | return 1; | |
725 | } else { | |
726 | /* Real code needs to emit a warning here */ | |
727 | } | |
728 | return 0; | |
729 | ||
730 | case ODEBUG_STATE_ACTIVE: | |
731 | debug_object_deactivate(obj, &descr_type_test); | |
732 | debug_object_activate(obj, &descr_type_test); | |
733 | return 1; | |
734 | ||
735 | default: | |
736 | return 0; | |
737 | } | |
738 | } | |
739 | ||
740 | /* | |
741 | * fixup_destroy is called when: | |
742 | * - an active object is destroyed | |
743 | */ | |
744 | static int __init fixup_destroy(void *addr, enum debug_obj_state state) | |
745 | { | |
746 | struct self_test *obj = addr; | |
747 | ||
748 | switch (state) { | |
749 | case ODEBUG_STATE_ACTIVE: | |
750 | debug_object_deactivate(obj, &descr_type_test); | |
751 | debug_object_destroy(obj, &descr_type_test); | |
752 | return 1; | |
753 | default: | |
754 | return 0; | |
755 | } | |
756 | } | |
757 | ||
758 | /* | |
759 | * fixup_free is called when: | |
760 | * - an active object is freed | |
761 | */ | |
762 | static int __init fixup_free(void *addr, enum debug_obj_state state) | |
763 | { | |
764 | struct self_test *obj = addr; | |
765 | ||
766 | switch (state) { | |
767 | case ODEBUG_STATE_ACTIVE: | |
768 | debug_object_deactivate(obj, &descr_type_test); | |
769 | debug_object_free(obj, &descr_type_test); | |
770 | return 1; | |
771 | default: | |
772 | return 0; | |
773 | } | |
774 | } | |
775 | ||
776 | static int | |
777 | check_results(void *addr, enum debug_obj_state state, int fixups, int warnings) | |
778 | { | |
779 | struct debug_bucket *db; | |
780 | struct debug_obj *obj; | |
781 | unsigned long flags; | |
782 | int res = -EINVAL; | |
783 | ||
784 | db = get_bucket((unsigned long) addr); | |
785 | ||
aef9cb05 | 786 | raw_spin_lock_irqsave(&db->lock, flags); |
3ac7fe5a TG |
787 | |
788 | obj = lookup_object(addr, db); | |
789 | if (!obj && state != ODEBUG_STATE_NONE) { | |
5cd2b459 | 790 | WARN(1, KERN_ERR "ODEBUG: selftest object not found\n"); |
3ac7fe5a TG |
791 | goto out; |
792 | } | |
793 | if (obj && obj->state != state) { | |
5cd2b459 | 794 | WARN(1, KERN_ERR "ODEBUG: selftest wrong state: %d != %d\n", |
3ac7fe5a | 795 | obj->state, state); |
3ac7fe5a TG |
796 | goto out; |
797 | } | |
798 | if (fixups != debug_objects_fixups) { | |
5cd2b459 | 799 | WARN(1, KERN_ERR "ODEBUG: selftest fixups failed %d != %d\n", |
3ac7fe5a | 800 | fixups, debug_objects_fixups); |
3ac7fe5a TG |
801 | goto out; |
802 | } | |
803 | if (warnings != debug_objects_warnings) { | |
5cd2b459 | 804 | WARN(1, KERN_ERR "ODEBUG: selftest warnings failed %d != %d\n", |
3ac7fe5a | 805 | warnings, debug_objects_warnings); |
3ac7fe5a TG |
806 | goto out; |
807 | } | |
808 | res = 0; | |
809 | out: | |
aef9cb05 | 810 | raw_spin_unlock_irqrestore(&db->lock, flags); |
3ac7fe5a TG |
811 | if (res) |
812 | debug_objects_enabled = 0; | |
813 | return res; | |
814 | } | |
815 | ||
816 | static __initdata struct debug_obj_descr descr_type_test = { | |
817 | .name = "selftest", | |
818 | .fixup_init = fixup_init, | |
819 | .fixup_activate = fixup_activate, | |
820 | .fixup_destroy = fixup_destroy, | |
821 | .fixup_free = fixup_free, | |
822 | }; | |
823 | ||
824 | static __initdata struct self_test obj = { .static_init = 0 }; | |
825 | ||
826 | static void __init debug_objects_selftest(void) | |
827 | { | |
828 | int fixups, oldfixups, warnings, oldwarnings; | |
829 | unsigned long flags; | |
830 | ||
831 | local_irq_save(flags); | |
832 | ||
833 | fixups = oldfixups = debug_objects_fixups; | |
834 | warnings = oldwarnings = debug_objects_warnings; | |
835 | descr_test = &descr_type_test; | |
836 | ||
837 | debug_object_init(&obj, &descr_type_test); | |
838 | if (check_results(&obj, ODEBUG_STATE_INIT, fixups, warnings)) | |
839 | goto out; | |
840 | debug_object_activate(&obj, &descr_type_test); | |
841 | if (check_results(&obj, ODEBUG_STATE_ACTIVE, fixups, warnings)) | |
842 | goto out; | |
843 | debug_object_activate(&obj, &descr_type_test); | |
844 | if (check_results(&obj, ODEBUG_STATE_ACTIVE, ++fixups, ++warnings)) | |
845 | goto out; | |
846 | debug_object_deactivate(&obj, &descr_type_test); | |
847 | if (check_results(&obj, ODEBUG_STATE_INACTIVE, fixups, warnings)) | |
848 | goto out; | |
849 | debug_object_destroy(&obj, &descr_type_test); | |
850 | if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, warnings)) | |
851 | goto out; | |
852 | debug_object_init(&obj, &descr_type_test); | |
853 | if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, ++warnings)) | |
854 | goto out; | |
855 | debug_object_activate(&obj, &descr_type_test); | |
856 | if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, ++warnings)) | |
857 | goto out; | |
858 | debug_object_deactivate(&obj, &descr_type_test); | |
859 | if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, ++warnings)) | |
860 | goto out; | |
861 | debug_object_free(&obj, &descr_type_test); | |
862 | if (check_results(&obj, ODEBUG_STATE_NONE, fixups, warnings)) | |
863 | goto out; | |
864 | ||
865 | obj.static_init = 1; | |
866 | debug_object_activate(&obj, &descr_type_test); | |
867 | if (check_results(&obj, ODEBUG_STATE_ACTIVE, ++fixups, warnings)) | |
868 | goto out; | |
869 | debug_object_init(&obj, &descr_type_test); | |
870 | if (check_results(&obj, ODEBUG_STATE_INIT, ++fixups, ++warnings)) | |
871 | goto out; | |
872 | debug_object_free(&obj, &descr_type_test); | |
873 | if (check_results(&obj, ODEBUG_STATE_NONE, fixups, warnings)) | |
874 | goto out; | |
875 | ||
876 | #ifdef CONFIG_DEBUG_OBJECTS_FREE | |
877 | debug_object_init(&obj, &descr_type_test); | |
878 | if (check_results(&obj, ODEBUG_STATE_INIT, fixups, warnings)) | |
879 | goto out; | |
880 | debug_object_activate(&obj, &descr_type_test); | |
881 | if (check_results(&obj, ODEBUG_STATE_ACTIVE, fixups, warnings)) | |
882 | goto out; | |
883 | __debug_check_no_obj_freed(&obj, sizeof(obj)); | |
884 | if (check_results(&obj, ODEBUG_STATE_NONE, ++fixups, ++warnings)) | |
885 | goto out; | |
886 | #endif | |
887 | printk(KERN_INFO "ODEBUG: selftest passed\n"); | |
888 | ||
889 | out: | |
890 | debug_objects_fixups = oldfixups; | |
891 | debug_objects_warnings = oldwarnings; | |
892 | descr_test = NULL; | |
893 | ||
894 | local_irq_restore(flags); | |
895 | } | |
896 | #else | |
897 | static inline void debug_objects_selftest(void) { } | |
898 | #endif | |
899 | ||
900 | /* | |
901 | * Called during early boot to initialize the hash buckets and link | |
902 | * the static object pool objects into the poll list. After this call | |
903 | * the object tracker is fully operational. | |
904 | */ | |
905 | void __init debug_objects_early_init(void) | |
906 | { | |
907 | int i; | |
908 | ||
909 | for (i = 0; i < ODEBUG_HASH_SIZE; i++) | |
aef9cb05 | 910 | raw_spin_lock_init(&obj_hash[i].lock); |
3ac7fe5a TG |
911 | |
912 | for (i = 0; i < ODEBUG_POOL_SIZE; i++) | |
913 | hlist_add_head(&obj_static_pool[i].node, &obj_pool); | |
914 | } | |
915 | ||
1be1cb7b TG |
916 | /* |
917 | * Convert the statically allocated objects to dynamic ones: | |
918 | */ | |
919 | static int debug_objects_replace_static_objects(void) | |
920 | { | |
921 | struct debug_bucket *db = obj_hash; | |
922 | struct hlist_node *node, *tmp; | |
923 | struct debug_obj *obj, *new; | |
924 | HLIST_HEAD(objects); | |
925 | int i, cnt = 0; | |
926 | ||
927 | for (i = 0; i < ODEBUG_POOL_SIZE; i++) { | |
928 | obj = kmem_cache_zalloc(obj_cache, GFP_KERNEL); | |
929 | if (!obj) | |
930 | goto free; | |
931 | hlist_add_head(&obj->node, &objects); | |
932 | } | |
933 | ||
934 | /* | |
935 | * When debug_objects_mem_init() is called we know that only | |
936 | * one CPU is up, so disabling interrupts is enough | |
937 | * protection. This avoids the lockdep hell of lock ordering. | |
938 | */ | |
939 | local_irq_disable(); | |
940 | ||
941 | /* Remove the statically allocated objects from the pool */ | |
942 | hlist_for_each_entry_safe(obj, node, tmp, &obj_pool, node) | |
943 | hlist_del(&obj->node); | |
944 | /* Move the allocated objects to the pool */ | |
945 | hlist_move_list(&objects, &obj_pool); | |
946 | ||
947 | /* Replace the active object references */ | |
948 | for (i = 0; i < ODEBUG_HASH_SIZE; i++, db++) { | |
949 | hlist_move_list(&db->list, &objects); | |
950 | ||
951 | hlist_for_each_entry(obj, node, &objects, node) { | |
952 | new = hlist_entry(obj_pool.first, typeof(*obj), node); | |
953 | hlist_del(&new->node); | |
954 | /* copy object data */ | |
955 | *new = *obj; | |
956 | hlist_add_head(&new->node, &db->list); | |
957 | cnt++; | |
958 | } | |
959 | } | |
960 | ||
961 | printk(KERN_DEBUG "ODEBUG: %d of %d active objects replaced\n", cnt, | |
962 | obj_pool_used); | |
963 | local_irq_enable(); | |
964 | return 0; | |
965 | free: | |
966 | hlist_for_each_entry_safe(obj, node, tmp, &objects, node) { | |
967 | hlist_del(&obj->node); | |
968 | kmem_cache_free(obj_cache, obj); | |
969 | } | |
970 | return -ENOMEM; | |
971 | } | |
972 | ||
3ac7fe5a TG |
973 | /* |
974 | * Called after the kmem_caches are functional to setup a dedicated | |
975 | * cache pool, which has the SLAB_DEBUG_OBJECTS flag set. This flag | |
976 | * prevents that the debug code is called on kmem_cache_free() for the | |
977 | * debug tracker objects to avoid recursive calls. | |
978 | */ | |
979 | void __init debug_objects_mem_init(void) | |
980 | { | |
981 | if (!debug_objects_enabled) | |
982 | return; | |
983 | ||
984 | obj_cache = kmem_cache_create("debug_objects_cache", | |
985 | sizeof (struct debug_obj), 0, | |
986 | SLAB_DEBUG_OBJECTS, NULL); | |
987 | ||
1be1cb7b | 988 | if (!obj_cache || debug_objects_replace_static_objects()) { |
3ac7fe5a | 989 | debug_objects_enabled = 0; |
1be1cb7b TG |
990 | if (obj_cache) |
991 | kmem_cache_destroy(obj_cache); | |
992 | printk(KERN_WARNING "ODEBUG: out of memory.\n"); | |
993 | } else | |
3ac7fe5a TG |
994 | debug_objects_selftest(); |
995 | } |