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GUI: Fix Tomato RAF theme for all builds. Compilation typo.
[tomato.git] / release / src-rt-6.x.4708 / linux / linux-2.6.36 / lib / debugobjects.c
blobdeebcc57d4e6a77e334dacb3b46c703e5c673515
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>
12 #include <linux/sched.h>
13 #include <linux/seq_file.h>
14 #include <linux/debugfs.h>
15 #include <linux/slab.h>
16 #include <linux/hash.h>
17
18 #define ODEBUG_HASH_BITS 14
19 #define ODEBUG_HASH_SIZE (1 << ODEBUG_HASH_BITS)
20
21 #define ODEBUG_POOL_SIZE 512
22 #define ODEBUG_POOL_MIN_LEVEL 256
23
24 #define ODEBUG_CHUNK_SHIFT PAGE_SHIFT
25 #define ODEBUG_CHUNK_SIZE (1 << ODEBUG_CHUNK_SHIFT)
26 #define ODEBUG_CHUNK_MASK (~(ODEBUG_CHUNK_SIZE - 1))
27
28 struct debug_bucket {
29 struct hlist_head list;
30 raw_spinlock_t lock;
31 };
32
33 static struct debug_bucket obj_hash[ODEBUG_HASH_SIZE];
34
35 static struct debug_obj obj_static_pool[ODEBUG_POOL_SIZE] __initdata;
36
37 static DEFINE_RAW_SPINLOCK(pool_lock);
38
39 static HLIST_HEAD(obj_pool);
40
41 static int obj_pool_min_free = ODEBUG_POOL_SIZE;
42 static int obj_pool_free = ODEBUG_POOL_SIZE;
43 static int obj_pool_used;
44 static int obj_pool_max_used;
45 static struct kmem_cache *obj_cache;
46
47 static int debug_objects_maxchain __read_mostly;
48 static int debug_objects_fixups __read_mostly;
49 static int debug_objects_warnings __read_mostly;
50 static int debug_objects_enabled __read_mostly
51 = CONFIG_DEBUG_OBJECTS_ENABLE_DEFAULT;
52
53 static struct debug_obj_descr *descr_test __read_mostly;
54
55 static void free_obj_work(struct work_struct *work);
56 static DECLARE_WORK(debug_obj_work, free_obj_work);
57
58 static int __init enable_object_debug(char *str)
59 {
60 debug_objects_enabled = 1;
61 return 0;
62 }
63
64 static int __init disable_object_debug(char *str)
65 {
66 debug_objects_enabled = 0;
67 return 0;
68 }
69
70 early_param("debug_objects", enable_object_debug);
71 early_param("no_debug_objects", disable_object_debug);
72
73 static const char *obj_states[ODEBUG_STATE_MAX] = {
74 [ODEBUG_STATE_NONE] = "none",
75 [ODEBUG_STATE_INIT] = "initialized",
76 [ODEBUG_STATE_INACTIVE] = "inactive",
77 [ODEBUG_STATE_ACTIVE] = "active",
78 [ODEBUG_STATE_DESTROYED] = "destroyed",
79 [ODEBUG_STATE_NOTAVAILABLE] = "not available",
80 };
81
82 static int fill_pool(void)
83 {
84 gfp_t gfp = GFP_ATOMIC | __GFP_NORETRY | __GFP_NOWARN;
85 struct debug_obj *new;
86 unsigned long flags;
87
88 if (likely(obj_pool_free >= ODEBUG_POOL_MIN_LEVEL))
89 return obj_pool_free;
90
91 if (unlikely(!obj_cache))
92 return obj_pool_free;
93
94 while (obj_pool_free < ODEBUG_POOL_MIN_LEVEL) {
95
96 new = kmem_cache_zalloc(obj_cache, gfp);
97 if (!new)
98 return obj_pool_free;
99
100 raw_spin_lock_irqsave(&pool_lock, flags);
101 hlist_add_head(&new->node, &obj_pool);
102 obj_pool_free++;
103 raw_spin_unlock_irqrestore(&pool_lock, flags);
104 }
105 return obj_pool_free;
106 }
107
108 /*
109 * Lookup an object in the hash bucket.
110 */
111 static struct debug_obj *lookup_object(void *addr, struct debug_bucket *b)
112 {
113 struct hlist_node *node;
114 struct debug_obj *obj;
115 int cnt = 0;
116
117 hlist_for_each_entry(obj, node, &b->list, node) {
118 cnt++;
119 if (obj->object == addr)
120 return obj;
121 }
122 if (cnt > debug_objects_maxchain)
123 debug_objects_maxchain = cnt;
124
125 return NULL;
126 }
127
128 /*
129 * Allocate a new object. If the pool is empty, switch off the debugger.
130 * Must be called with interrupts disabled.
131 */
132 static struct debug_obj *
133 alloc_object(void *addr, struct debug_bucket *b, struct debug_obj_descr *descr)
134 {
135 struct debug_obj *obj = NULL;
136
137 raw_spin_lock(&pool_lock);
138 if (obj_pool.first) {
139 obj = hlist_entry(obj_pool.first, typeof(*obj), node);
140
141 obj->object = addr;
142 obj->descr = descr;
143 obj->state = ODEBUG_STATE_NONE;
144 obj->astate = 0;
145 hlist_del(&obj->node);
146
147 hlist_add_head(&obj->node, &b->list);
148
149 obj_pool_used++;
150 if (obj_pool_used > obj_pool_max_used)
151 obj_pool_max_used = obj_pool_used;
152
153 obj_pool_free--;
154 if (obj_pool_free < obj_pool_min_free)
155 obj_pool_min_free = obj_pool_free;
156 }
157 raw_spin_unlock(&pool_lock);
158
159 return obj;
160 }
161
162 /*
163 * workqueue function to free objects.
164 */
165 static void free_obj_work(struct work_struct *work)
166 {
167 struct debug_obj *obj;
168 unsigned long flags;
169
170 raw_spin_lock_irqsave(&pool_lock, flags);
171 while (obj_pool_free > ODEBUG_POOL_SIZE) {
172 obj = hlist_entry(obj_pool.first, typeof(*obj), node);
173 hlist_del(&obj->node);
174 obj_pool_free--;
175 /*
176 * We release pool_lock across kmem_cache_free() to
177 * avoid contention on pool_lock.
178 */
179 raw_spin_unlock_irqrestore(&pool_lock, flags);
180 kmem_cache_free(obj_cache, obj);
181 raw_spin_lock_irqsave(&pool_lock, flags);
182 }
183 raw_spin_unlock_irqrestore(&pool_lock, flags);
184 }
185
186 /*
187 * Put the object back into the pool and schedule work to free objects
188 * if necessary.
189 */
190 static void free_object(struct debug_obj *obj)
191 {
192 unsigned long flags;
193 int sched = 0;
194
195 raw_spin_lock_irqsave(&pool_lock, flags);
196 /*
197 * schedule work when the pool is filled and the cache is
198 * initialized:
199 */
200 if (obj_pool_free > ODEBUG_POOL_SIZE && obj_cache)
201 sched = !work_pending(&debug_obj_work);
202 hlist_add_head(&obj->node, &obj_pool);
203 obj_pool_free++;
204 obj_pool_used--;
205 raw_spin_unlock_irqrestore(&pool_lock, flags);
206 if (sched)
207 schedule_work(&debug_obj_work);
208 }
209
210 /*
211 * We run out of memory. That means we probably have tons of objects
212 * allocated.
213 */
214 static void debug_objects_oom(void)
215 {
216 struct debug_bucket *db = obj_hash;
217 struct hlist_node *node, *tmp;
218 HLIST_HEAD(freelist);
219 struct debug_obj *obj;
220 unsigned long flags;
221 int i;
222
223 printk(KERN_WARNING "ODEBUG: Out of memory. ODEBUG disabled\n");
224
225 for (i = 0; i < ODEBUG_HASH_SIZE; i++, db++) {
226 raw_spin_lock_irqsave(&db->lock, flags);
227 hlist_move_list(&db->list, &freelist);
228 raw_spin_unlock_irqrestore(&db->lock, flags);
229
230 /* Now free them */
231 hlist_for_each_entry_safe(obj, node, tmp, &freelist, node) {
232 hlist_del(&obj->node);
233 free_object(obj);
234 }
235 }
236 }
237
238 /*
239 * We use the pfn of the address for the hash. That way we can check
240 * for freed objects simply by checking the affected bucket.
241 */
242 static struct debug_bucket *get_bucket(unsigned long addr)
243 {
244 unsigned long hash;
245
246 hash = hash_long((addr >> ODEBUG_CHUNK_SHIFT), ODEBUG_HASH_BITS);
247 return &obj_hash[hash];
248 }
249
250 static void debug_print_object(struct debug_obj *obj, char *msg)
251 {
252 static int limit;
253
254 if (limit < 5 && obj->descr != descr_test) {
255 limit++;
256 WARN(1, KERN_ERR "ODEBUG: %s %s (active state %u) "
257 "object type: %s\n",
258 msg, obj_states[obj->state], obj->astate,
259 obj->descr->name);
260 }
261 debug_objects_warnings++;
262 }
263
264 /*
265 * Try to repair the damage, so we have a better chance to get useful
266 * debug output.
267 */
268 static void
269 debug_object_fixup(int (*fixup)(void *addr, enum debug_obj_state state),
270 void * addr, enum debug_obj_state state)
271 {
272 if (fixup)
273 debug_objects_fixups += fixup(addr, state);
274 }
275
276 static void debug_object_is_on_stack(void *addr, int onstack)
277 {
278 int is_on_stack;
279 static int limit;
280
281 if (limit > 4)
282 return;
283
284 is_on_stack = object_is_on_stack(addr);
285 if (is_on_stack == onstack)
286 return;
287
288 limit++;
289 if (is_on_stack)
290 printk(KERN_WARNING
291 "ODEBUG: object is on stack, but not annotated\n");
292 else
293 printk(KERN_WARNING
294 "ODEBUG: object is not on stack, but annotated\n");
295 WARN_ON(1);
296 }
297
298 static void
299 __debug_object_init(void *addr, struct debug_obj_descr *descr, int onstack)
300 {
301 enum debug_obj_state state;
302 struct debug_bucket *db;
303 struct debug_obj *obj;
304 unsigned long flags;
305
306 fill_pool();
307
308 db = get_bucket((unsigned long) addr);
309
310 raw_spin_lock_irqsave(&db->lock, flags);
311
312 obj = lookup_object(addr, db);
313 if (!obj) {
314 obj = alloc_object(addr, db, descr);
315 if (!obj) {
316 debug_objects_enabled = 0;
317 raw_spin_unlock_irqrestore(&db->lock, flags);
318 debug_objects_oom();
319 return;
320 }
321 debug_object_is_on_stack(addr, onstack);
322 }
323
324 switch (obj->state) {
325 case ODEBUG_STATE_NONE:
326 case ODEBUG_STATE_INIT:
327 case ODEBUG_STATE_INACTIVE:
328 obj->state = ODEBUG_STATE_INIT;
329 break;
330
331 case ODEBUG_STATE_ACTIVE:
332 debug_print_object(obj, "init");
333 state = obj->state;
334 raw_spin_unlock_irqrestore(&db->lock, flags);
335 debug_object_fixup(descr->fixup_init, addr, state);
336 return;
337
338 case ODEBUG_STATE_DESTROYED:
339 debug_print_object(obj, "init");
340 break;
341 default:
342 break;
343 }
344
345 raw_spin_unlock_irqrestore(&db->lock, flags);
346 }
347
348 /**
349 * debug_object_init - debug checks when an object is initialized
350 * @addr: address of the object
351 * @descr: pointer to an object specific debug description structure
352 */
353 void debug_object_init(void *addr, struct debug_obj_descr *descr)
354 {
355 if (!debug_objects_enabled)
356 return;
357
358 __debug_object_init(addr, descr, 0);
359 }
360
361 /**
362 * debug_object_init_on_stack - debug checks when an object on stack is
363 * initialized
364 * @addr: address of the object
365 * @descr: pointer to an object specific debug description structure
366 */
367 void debug_object_init_on_stack(void *addr, struct debug_obj_descr *descr)
368 {
369 if (!debug_objects_enabled)
370 return;
371
372 __debug_object_init(addr, descr, 1);
373 }
374
375 /**
376 * debug_object_activate - debug checks when an object is activated
377 * @addr: address of the object
378 * @descr: pointer to an object specific debug description structure
379 */
380 void debug_object_activate(void *addr, struct debug_obj_descr *descr)
381 {
382 enum debug_obj_state state;
383 struct debug_bucket *db;
384 struct debug_obj *obj;
385 unsigned long flags;
386
387 if (!debug_objects_enabled)
388 return;
389
390 db = get_bucket((unsigned long) addr);
391
392 raw_spin_lock_irqsave(&db->lock, flags);
393
394 obj = lookup_object(addr, db);
395 if (obj) {
396 switch (obj->state) {
397 case ODEBUG_STATE_INIT:
398 case ODEBUG_STATE_INACTIVE:
399 obj->state = ODEBUG_STATE_ACTIVE;
400 break;
401
402 case ODEBUG_STATE_ACTIVE:
403 debug_print_object(obj, "activate");
404 state = obj->state;
405 raw_spin_unlock_irqrestore(&db->lock, flags);
406 debug_object_fixup(descr->fixup_activate, addr, state);
407 return;
408
409 case ODEBUG_STATE_DESTROYED:
410 debug_print_object(obj, "activate");
411 break;
412 default:
413 break;
414 }
415 raw_spin_unlock_irqrestore(&db->lock, flags);
416 return;
417 }
418
419 raw_spin_unlock_irqrestore(&db->lock, flags);
420 /*
421 * This happens when a static object is activated. We
422 * let the type specific code decide whether this is
423 * true or not.
424 */
425 debug_object_fixup(descr->fixup_activate, addr,
426 ODEBUG_STATE_NOTAVAILABLE);
427 }
428
429 /**
430 * debug_object_deactivate - debug checks when an object is deactivated
431 * @addr: address of the object
432 * @descr: pointer to an object specific debug description structure
433 */
434 void debug_object_deactivate(void *addr, struct debug_obj_descr *descr)
435 {
436 struct debug_bucket *db;
437 struct debug_obj *obj;
438 unsigned long flags;
439
440 if (!debug_objects_enabled)
441 return;
442
443 db = get_bucket((unsigned long) addr);
444
445 raw_spin_lock_irqsave(&db->lock, flags);
446
447 obj = lookup_object(addr, db);
448 if (obj) {
449 switch (obj->state) {
450 case ODEBUG_STATE_INIT:
451 case ODEBUG_STATE_INACTIVE:
452 case ODEBUG_STATE_ACTIVE:
453 if (!obj->astate)
454 obj->state = ODEBUG_STATE_INACTIVE;
455 else
456 debug_print_object(obj, "deactivate");
457 break;
458
459 case ODEBUG_STATE_DESTROYED:
460 debug_print_object(obj, "deactivate");
461 break;
462 default:
463 break;
464 }
465 } else {
466 struct debug_obj o = { .object = addr,
467 .state = ODEBUG_STATE_NOTAVAILABLE,
468 .descr = descr };
469
470 debug_print_object(&o, "deactivate");
471 }
472
473 raw_spin_unlock_irqrestore(&db->lock, flags);
474 }
475
476 /**
477 * debug_object_destroy - debug checks when an object is destroyed
478 * @addr: address of the object
479 * @descr: pointer to an object specific debug description structure
480 */
481 void debug_object_destroy(void *addr, struct debug_obj_descr *descr)
482 {
483 enum debug_obj_state state;
484 struct debug_bucket *db;
485 struct debug_obj *obj;
486 unsigned long flags;
487
488 if (!debug_objects_enabled)
489 return;
490
491 db = get_bucket((unsigned long) addr);
492
493 raw_spin_lock_irqsave(&db->lock, flags);
494
495 obj = lookup_object(addr, db);
496 if (!obj)
497 goto out_unlock;
498
499 switch (obj->state) {
500 case ODEBUG_STATE_NONE:
501 case ODEBUG_STATE_INIT:
502 case ODEBUG_STATE_INACTIVE:
503 obj->state = ODEBUG_STATE_DESTROYED;
504 break;
505 case ODEBUG_STATE_ACTIVE:
506 debug_print_object(obj, "destroy");
507 state = obj->state;
508 raw_spin_unlock_irqrestore(&db->lock, flags);
509 debug_object_fixup(descr->fixup_destroy, addr, state);
510 return;
511
512 case ODEBUG_STATE_DESTROYED:
513 debug_print_object(obj, "destroy");
514 break;
515 default:
516 break;
517 }
518 out_unlock:
519 raw_spin_unlock_irqrestore(&db->lock, flags);
520 }
521
522 /**
523 * debug_object_free - debug checks when an object is freed
524 * @addr: address of the object
525 * @descr: pointer to an object specific debug description structure
526 */
527 void debug_object_free(void *addr, struct debug_obj_descr *descr)
528 {
529 enum debug_obj_state state;
530 struct debug_bucket *db;
531 struct debug_obj *obj;
532 unsigned long flags;
533
534 if (!debug_objects_enabled)
535 return;
536
537 db = get_bucket((unsigned long) addr);
538
539 raw_spin_lock_irqsave(&db->lock, flags);
540
541 obj = lookup_object(addr, db);
542 if (!obj)
543 goto out_unlock;
544
545 switch (obj->state) {
546 case ODEBUG_STATE_ACTIVE:
547 debug_print_object(obj, "free");
548 state = obj->state;
549 raw_spin_unlock_irqrestore(&db->lock, flags);
550 debug_object_fixup(descr->fixup_free, addr, state);
551 return;
552 default:
553 hlist_del(&obj->node);
554 raw_spin_unlock_irqrestore(&db->lock, flags);
555 free_object(obj);
556 return;
557 }
558 out_unlock:
559 raw_spin_unlock_irqrestore(&db->lock, flags);
560 }
561
562 /**
563 * debug_object_active_state - debug checks object usage state machine
564 * @addr: address of the object
565 * @descr: pointer to an object specific debug description structure
566 * @expect: expected state
567 * @next: state to move to if expected state is found
568 */
569 void
570 debug_object_active_state(void *addr, struct debug_obj_descr *descr,
571 unsigned int expect, unsigned int next)
572 {
573 struct debug_bucket *db;
574 struct debug_obj *obj;
575 unsigned long flags;
576
577 if (!debug_objects_enabled)
578 return;
579
580 db = get_bucket((unsigned long) addr);
581
582 raw_spin_lock_irqsave(&db->lock, flags);
583
584 obj = lookup_object(addr, db);
585 if (obj) {
586 switch (obj->state) {
587 case ODEBUG_STATE_ACTIVE:
588 if (obj->astate == expect)
589 obj->astate = next;
590 else
591 debug_print_object(obj, "active_state");
592 break;
593
594 default:
595 debug_print_object(obj, "active_state");
596 break;
597 }
598 } else {
599 struct debug_obj o = { .object = addr,
600 .state = ODEBUG_STATE_NOTAVAILABLE,
601 .descr = descr };
602
603 debug_print_object(&o, "active_state");
604 }
605
606 raw_spin_unlock_irqrestore(&db->lock, flags);
607 }
608
609 #ifdef CONFIG_DEBUG_OBJECTS_FREE
610 static void __debug_check_no_obj_freed(const void *address, unsigned long size)
611 {
612 unsigned long flags, oaddr, saddr, eaddr, paddr, chunks;
613 struct hlist_node *node, *tmp;
614 HLIST_HEAD(freelist);
615 struct debug_obj_descr *descr;
616 enum debug_obj_state state;
617 struct debug_bucket *db;
618 struct debug_obj *obj;
619 int cnt;
620
621 saddr = (unsigned long) address;
622 eaddr = saddr + size;
623 paddr = saddr & ODEBUG_CHUNK_MASK;
624 chunks = ((eaddr - paddr) + (ODEBUG_CHUNK_SIZE - 1));
625 chunks >>= ODEBUG_CHUNK_SHIFT;
626
627 for (;chunks > 0; chunks--, paddr += ODEBUG_CHUNK_SIZE) {
628 db = get_bucket(paddr);
629
630 repeat:
631 cnt = 0;
632 raw_spin_lock_irqsave(&db->lock, flags);
633 hlist_for_each_entry_safe(obj, node, tmp, &db->list, node) {
634 cnt++;
635 oaddr = (unsigned long) obj->object;
636 if (oaddr < saddr || oaddr >= eaddr)
637 continue;
638
639 switch (obj->state) {
640 case ODEBUG_STATE_ACTIVE:
641 debug_print_object(obj, "free");
642 descr = obj->descr;
643 state = obj->state;
644 raw_spin_unlock_irqrestore(&db->lock, flags);
645 debug_object_fixup(descr->fixup_free,
646 (void *) oaddr, state);
647 goto repeat;
648 default:
649 hlist_del(&obj->node);
650 hlist_add_head(&obj->node, &freelist);
651 break;
652 }
653 }
654 raw_spin_unlock_irqrestore(&db->lock, flags);
655
656 /* Now free them */
657 hlist_for_each_entry_safe(obj, node, tmp, &freelist, node) {
658 hlist_del(&obj->node);
659 free_object(obj);
660 }
661
662 if (cnt > debug_objects_maxchain)
663 debug_objects_maxchain = cnt;
664 }
665 }
666
667 void debug_check_no_obj_freed(const void *address, unsigned long size)
668 {
669 if (debug_objects_enabled)
670 __debug_check_no_obj_freed(address, size);
671 }
672 #endif
673
674 #ifdef CONFIG_DEBUG_FS
675
676 static int debug_stats_show(struct seq_file *m, void *v)
677 {
678 seq_printf(m, "max_chain :%d\n", debug_objects_maxchain);
679 seq_printf(m, "warnings :%d\n", debug_objects_warnings);
680 seq_printf(m, "fixups :%d\n", debug_objects_fixups);
681 seq_printf(m, "pool_free :%d\n", obj_pool_free);
682 seq_printf(m, "pool_min_free :%d\n", obj_pool_min_free);
683 seq_printf(m, "pool_used :%d\n", obj_pool_used);
684 seq_printf(m, "pool_max_used :%d\n", obj_pool_max_used);
685 return 0;
686 }
687
688 static int debug_stats_open(struct inode *inode, struct file *filp)
689 {
690 return single_open(filp, debug_stats_show, NULL);
691 }
692
693 static const struct file_operations debug_stats_fops = {
694 .open = debug_stats_open,
695 .read = seq_read,
696 .llseek = seq_lseek,
697 .release = single_release,
698 };
699
700 static int __init debug_objects_init_debugfs(void)
701 {
702 struct dentry *dbgdir, *dbgstats;
703
704 if (!debug_objects_enabled)
705 return 0;
706
707 dbgdir = debugfs_create_dir("debug_objects", NULL);
708 if (!dbgdir)
709 return -ENOMEM;
710
711 dbgstats = debugfs_create_file("stats", 0444, dbgdir, NULL,
712 &debug_stats_fops);
713 if (!dbgstats)
714 goto err;
715
716 return 0;
717
718 err:
719 debugfs_remove(dbgdir);
720
721 return -ENOMEM;
722 }
723 __initcall(debug_objects_init_debugfs);
724
725 #else
726 static inline void debug_objects_init_debugfs(void) { }
727 #endif
728
729 #ifdef CONFIG_DEBUG_OBJECTS_SELFTEST
730
731 /* Random data structure for the self test */
732 struct self_test {
733 unsigned long dummy1[6];
734 int static_init;
735 unsigned long dummy2[3];
736 };
737
738 static __initdata struct debug_obj_descr descr_type_test;
739
740 /*
741 * fixup_init is called when:
742 * - an active object is initialized
743 */
744 static int __init fixup_init(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_init(obj, &descr_type_test);
752 return 1;
753 default:
754 return 0;
755 }
756 }
757
758 /*
759 * fixup_activate is called when:
760 * - an active object is activated
761 * - an unknown object is activated (might be a statically initialized object)
762 */
763 static int __init fixup_activate(void *addr, enum debug_obj_state state)
764 {
765 struct self_test *obj = addr;
766
767 switch (state) {
768 case ODEBUG_STATE_NOTAVAILABLE:
769 if (obj->static_init == 1) {
770 debug_object_init(obj, &descr_type_test);
771 debug_object_activate(obj, &descr_type_test);
772 /*
773 * Real code should return 0 here ! This is
774 * not a fixup of some bad behaviour. We
775 * merily call the debug_init function to keep
776 * track of the object.
777 */
778 return 1;
779 } else {
780 /* Real code needs to emit a warning here */
781 }
782 return 0;
783
784 case ODEBUG_STATE_ACTIVE:
785 debug_object_deactivate(obj, &descr_type_test);
786 debug_object_activate(obj, &descr_type_test);
787 return 1;
788
789 default:
790 return 0;
791 }
792 }
793
794 /*
795 * fixup_destroy is called when:
796 * - an active object is destroyed
797 */
798 static int __init fixup_destroy(void *addr, enum debug_obj_state state)
799 {
800 struct self_test *obj = addr;
801
802 switch (state) {
803 case ODEBUG_STATE_ACTIVE:
804 debug_object_deactivate(obj, &descr_type_test);
805 debug_object_destroy(obj, &descr_type_test);
806 return 1;
807 default:
808 return 0;
809 }
810 }
811
812 /*
813 * fixup_free is called when:
814 * - an active object is freed
815 */
816 static int __init fixup_free(void *addr, enum debug_obj_state state)
817 {
818 struct self_test *obj = addr;
819
820 switch (state) {
821 case ODEBUG_STATE_ACTIVE:
822 debug_object_deactivate(obj, &descr_type_test);
823 debug_object_free(obj, &descr_type_test);
824 return 1;
825 default:
826 return 0;
827 }
828 }
829
830 static int __init
831 check_results(void *addr, enum debug_obj_state state, int fixups, int warnings)
832 {
833 struct debug_bucket *db;
834 struct debug_obj *obj;
835 unsigned long flags;
836 int res = -EINVAL;
837
838 db = get_bucket((unsigned long) addr);
839
840 raw_spin_lock_irqsave(&db->lock, flags);
841
842 obj = lookup_object(addr, db);
843 if (!obj && state != ODEBUG_STATE_NONE) {
844 WARN(1, KERN_ERR "ODEBUG: selftest object not found\n");
845 goto out;
846 }
847 if (obj && obj->state != state) {
848 WARN(1, KERN_ERR "ODEBUG: selftest wrong state: %d != %d\n",
849 obj->state, state);
850 goto out;
851 }
852 if (fixups != debug_objects_fixups) {
853 WARN(1, KERN_ERR "ODEBUG: selftest fixups failed %d != %d\n",
854 fixups, debug_objects_fixups);
855 goto out;
856 }
857 if (warnings != debug_objects_warnings) {
858 WARN(1, KERN_ERR "ODEBUG: selftest warnings failed %d != %d\n",
859 warnings, debug_objects_warnings);
860 goto out;
861 }
862 res = 0;
863 out:
864 raw_spin_unlock_irqrestore(&db->lock, flags);
865 if (res)
866 debug_objects_enabled = 0;
867 return res;
868 }
869
870 static __initdata struct debug_obj_descr descr_type_test = {
871 .name = "selftest",
872 .fixup_init = fixup_init,
873 .fixup_activate = fixup_activate,
874 .fixup_destroy = fixup_destroy,
875 .fixup_free = fixup_free,
876 };
877
878 static __initdata struct self_test obj = { .static_init = 0 };
879
880 static void __init debug_objects_selftest(void)
881 {
882 int fixups, oldfixups, warnings, oldwarnings;
883 unsigned long flags;
884
885 local_irq_save(flags);
886
887 fixups = oldfixups = debug_objects_fixups;
888 warnings = oldwarnings = debug_objects_warnings;
889 descr_test = &descr_type_test;
890
891 debug_object_init(&obj, &descr_type_test);
892 if (check_results(&obj, ODEBUG_STATE_INIT, fixups, warnings))
893 goto out;
894 debug_object_activate(&obj, &descr_type_test);
895 if (check_results(&obj, ODEBUG_STATE_ACTIVE, fixups, warnings))
896 goto out;
897 debug_object_activate(&obj, &descr_type_test);
898 if (check_results(&obj, ODEBUG_STATE_ACTIVE, ++fixups, ++warnings))
899 goto out;
900 debug_object_deactivate(&obj, &descr_type_test);
901 if (check_results(&obj, ODEBUG_STATE_INACTIVE, fixups, warnings))
902 goto out;
903 debug_object_destroy(&obj, &descr_type_test);
904 if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, warnings))
905 goto out;
906 debug_object_init(&obj, &descr_type_test);
907 if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, ++warnings))
908 goto out;
909 debug_object_activate(&obj, &descr_type_test);
910 if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, ++warnings))
911 goto out;
912 debug_object_deactivate(&obj, &descr_type_test);
913 if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, ++warnings))
914 goto out;
915 debug_object_free(&obj, &descr_type_test);
916 if (check_results(&obj, ODEBUG_STATE_NONE, fixups, warnings))
917 goto out;
918
919 obj.static_init = 1;
920 debug_object_activate(&obj, &descr_type_test);
921 if (check_results(&obj, ODEBUG_STATE_ACTIVE, ++fixups, warnings))
922 goto out;
923 debug_object_init(&obj, &descr_type_test);
924 if (check_results(&obj, ODEBUG_STATE_INIT, ++fixups, ++warnings))
925 goto out;
926 debug_object_free(&obj, &descr_type_test);
927 if (check_results(&obj, ODEBUG_STATE_NONE, fixups, warnings))
928 goto out;
929
930 #ifdef CONFIG_DEBUG_OBJECTS_FREE
931 debug_object_init(&obj, &descr_type_test);
932 if (check_results(&obj, ODEBUG_STATE_INIT, fixups, warnings))
933 goto out;
934 debug_object_activate(&obj, &descr_type_test);
935 if (check_results(&obj, ODEBUG_STATE_ACTIVE, fixups, warnings))
936 goto out;
937 __debug_check_no_obj_freed(&obj, sizeof(obj));
938 if (check_results(&obj, ODEBUG_STATE_NONE, ++fixups, ++warnings))
939 goto out;
940 #endif
941 printk(KERN_INFO "ODEBUG: selftest passed\n");
942
943 out:
944 debug_objects_fixups = oldfixups;
945 debug_objects_warnings = oldwarnings;
946 descr_test = NULL;
947
948 local_irq_restore(flags);
949 }
950 #else
951 static inline void debug_objects_selftest(void) { }
952 #endif
953
954 /*
955 * Called during early boot to initialize the hash buckets and link
956 * the static object pool objects into the poll list. After this call
957 * the object tracker is fully operational.
958 */
959 void __init debug_objects_early_init(void)
960 {
961 int i;
962
963 for (i = 0; i < ODEBUG_HASH_SIZE; i++)
964 raw_spin_lock_init(&obj_hash[i].lock);
965
966 for (i = 0; i < ODEBUG_POOL_SIZE; i++)
967 hlist_add_head(&obj_static_pool[i].node, &obj_pool);
968 }
969
970 /*
971 * Convert the statically allocated objects to dynamic ones:
972 */
973 static int __init debug_objects_replace_static_objects(void)
974 {
975 struct debug_bucket *db = obj_hash;
976 struct hlist_node *node, *tmp;
977 struct debug_obj *obj, *new;
978 HLIST_HEAD(objects);
979 int i, cnt = 0;
980
981 for (i = 0; i < ODEBUG_POOL_SIZE; i++) {
982 obj = kmem_cache_zalloc(obj_cache, GFP_KERNEL);
983 if (!obj)
984 goto free;
985 hlist_add_head(&obj->node, &objects);
986 }
987
988 /*
989 * When debug_objects_mem_init() is called we know that only
990 * one CPU is up, so disabling interrupts is enough
991 * protection. This avoids the lockdep hell of lock ordering.
992 */
993 local_irq_disable();
994
995 /* Remove the statically allocated objects from the pool */
996 hlist_for_each_entry_safe(obj, node, tmp, &obj_pool, node)
997 hlist_del(&obj->node);
998 /* Move the allocated objects to the pool */
999 hlist_move_list(&objects, &obj_pool);
1000
1001 /* Replace the active object references */
1002 for (i = 0; i < ODEBUG_HASH_SIZE; i++, db++) {
1003 hlist_move_list(&db->list, &objects);
1004
1005 hlist_for_each_entry(obj, node, &objects, node) {
1006 new = hlist_entry(obj_pool.first, typeof(*obj), node);
1007 hlist_del(&new->node);
1008 /* copy object data */
1009 *new = *obj;
1010 hlist_add_head(&new->node, &db->list);
1011 cnt++;
1012 }
1013 }
1014
1015 printk(KERN_DEBUG "ODEBUG: %d of %d active objects replaced\n", cnt,
1016 obj_pool_used);
1017 local_irq_enable();
1018 return 0;
1019 free:
1020 hlist_for_each_entry_safe(obj, node, tmp, &objects, node) {
1021 hlist_del(&obj->node);
1022 kmem_cache_free(obj_cache, obj);
1023 }
1024 return -ENOMEM;
1025 }
1026
1027 /*
1028 * Called after the kmem_caches are functional to setup a dedicated
1029 * cache pool, which has the SLAB_DEBUG_OBJECTS flag set. This flag
1030 * prevents that the debug code is called on kmem_cache_free() for the
1031 * debug tracker objects to avoid recursive calls.
1032 */
1033 void __init debug_objects_mem_init(void)
1034 {
1035 if (!debug_objects_enabled)
1036 return;
1037
1038 obj_cache = kmem_cache_create("debug_objects_cache",
1039 sizeof (struct debug_obj), 0,
1040 SLAB_DEBUG_OBJECTS, NULL);
1041
1042 if (!obj_cache || debug_objects_replace_static_objects()) {
1043 debug_objects_enabled = 0;
1044 if (obj_cache)
1045 kmem_cache_destroy(obj_cache);
1046 printk(KERN_WARNING "ODEBUG: out of memory.\n");
1047 } else
1048 debug_objects_selftest();
1049 }
Tomato firmware and modifications.