Kconfig: eliminate "def_bool n" constructs
[linux-2.6.git] / lib / debugobjects.c
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/seq_file.h>
13 #include <linux/debugfs.h>
14 #include <linux/hash.h>
15
16 #define ODEBUG_HASH_BITS        14
17 #define ODEBUG_HASH_SIZE        (1 << ODEBUG_HASH_BITS)
18
19 #define ODEBUG_POOL_SIZE        512
20 #define ODEBUG_POOL_MIN_LEVEL   256
21
22 #define ODEBUG_CHUNK_SHIFT      PAGE_SHIFT
23 #define ODEBUG_CHUNK_SIZE       (1 << ODEBUG_CHUNK_SHIFT)
24 #define ODEBUG_CHUNK_MASK       (~(ODEBUG_CHUNK_SIZE - 1))
25
26 struct debug_bucket {
27         struct hlist_head       list;
28         spinlock_t              lock;
29 };
30
31 static struct debug_bucket      obj_hash[ODEBUG_HASH_SIZE];
32
33 static struct debug_obj         obj_static_pool[ODEBUG_POOL_SIZE];
34
35 static DEFINE_SPINLOCK(pool_lock);
36
37 static HLIST_HEAD(obj_pool);
38
39 static int                      obj_pool_min_free = ODEBUG_POOL_SIZE;
40 static int                      obj_pool_free = ODEBUG_POOL_SIZE;
41 static int                      obj_pool_used;
42 static int                      obj_pool_max_used;
43 static struct kmem_cache        *obj_cache;
44
45 static int                      debug_objects_maxchain __read_mostly;
46 static int                      debug_objects_fixups __read_mostly;
47 static int                      debug_objects_warnings __read_mostly;
48 static int                      debug_objects_enabled __read_mostly;
49 static struct debug_obj_descr   *descr_test  __read_mostly;
50
51 static int __init enable_object_debug(char *str)
52 {
53         debug_objects_enabled = 1;
54         return 0;
55 }
56 early_param("debug_objects", enable_object_debug);
57
58 static const char *obj_states[ODEBUG_STATE_MAX] = {
59         [ODEBUG_STATE_NONE]             = "none",
60         [ODEBUG_STATE_INIT]             = "initialized",
61         [ODEBUG_STATE_INACTIVE]         = "inactive",
62         [ODEBUG_STATE_ACTIVE]           = "active",
63         [ODEBUG_STATE_DESTROYED]        = "destroyed",
64         [ODEBUG_STATE_NOTAVAILABLE]     = "not available",
65 };
66
67 static int fill_pool(void)
68 {
69         gfp_t gfp = GFP_ATOMIC | __GFP_NORETRY | __GFP_NOWARN;
70         struct debug_obj *new;
71         unsigned long flags;
72
73         if (likely(obj_pool_free >= ODEBUG_POOL_MIN_LEVEL))
74                 return obj_pool_free;
75
76         if (unlikely(!obj_cache))
77                 return obj_pool_free;
78
79         while (obj_pool_free < ODEBUG_POOL_MIN_LEVEL) {
80
81                 new = kmem_cache_zalloc(obj_cache, gfp);
82                 if (!new)
83                         return obj_pool_free;
84
85                 spin_lock_irqsave(&pool_lock, flags);
86                 hlist_add_head(&new->node, &obj_pool);
87                 obj_pool_free++;
88                 spin_unlock_irqrestore(&pool_lock, flags);
89         }
90         return obj_pool_free;
91 }
92
93 /*
94  * Lookup an object in the hash bucket.
95  */
96 static struct debug_obj *lookup_object(void *addr, struct debug_bucket *b)
97 {
98         struct hlist_node *node;
99         struct debug_obj *obj;
100         int cnt = 0;
101
102         hlist_for_each_entry(obj, node, &b->list, node) {
103                 cnt++;
104                 if (obj->object == addr)
105                         return obj;
106         }
107         if (cnt > debug_objects_maxchain)
108                 debug_objects_maxchain = cnt;
109
110         return NULL;
111 }
112
113 /*
114  * Allocate a new object. If the pool is empty, switch off the debugger.
115  * Must be called with interrupts disabled.
116  */
117 static struct debug_obj *
118 alloc_object(void *addr, struct debug_bucket *b, struct debug_obj_descr *descr)
119 {
120         struct debug_obj *obj = NULL;
121
122         spin_lock(&pool_lock);
123         if (obj_pool.first) {
124                 obj         = hlist_entry(obj_pool.first, typeof(*obj), node);
125
126                 obj->object = addr;
127                 obj->descr  = descr;
128                 obj->state  = ODEBUG_STATE_NONE;
129                 hlist_del(&obj->node);
130
131                 hlist_add_head(&obj->node, &b->list);
132
133                 obj_pool_used++;
134                 if (obj_pool_used > obj_pool_max_used)
135                         obj_pool_max_used = obj_pool_used;
136
137                 obj_pool_free--;
138                 if (obj_pool_free < obj_pool_min_free)
139                         obj_pool_min_free = obj_pool_free;
140         }
141         spin_unlock(&pool_lock);
142
143         return obj;
144 }
145
146 /*
147  * Put the object back into the pool or give it back to kmem_cache:
148  */
149 static void free_object(struct debug_obj *obj)
150 {
151         unsigned long idx = (unsigned long)(obj - obj_static_pool);
152         unsigned long flags;
153
154         if (obj_pool_free < ODEBUG_POOL_SIZE || idx < ODEBUG_POOL_SIZE) {
155                 spin_lock_irqsave(&pool_lock, flags);
156                 hlist_add_head(&obj->node, &obj_pool);
157                 obj_pool_free++;
158                 obj_pool_used--;
159                 spin_unlock_irqrestore(&pool_lock, flags);
160         } else {
161                 spin_lock_irqsave(&pool_lock, flags);
162                 obj_pool_used--;
163                 spin_unlock_irqrestore(&pool_lock, flags);
164                 kmem_cache_free(obj_cache, obj);
165         }
166 }
167
168 /*
169  * We run out of memory. That means we probably have tons of objects
170  * allocated.
171  */
172 static void debug_objects_oom(void)
173 {
174         struct debug_bucket *db = obj_hash;
175         struct hlist_node *node, *tmp;
176         HLIST_HEAD(freelist);
177         struct debug_obj *obj;
178         unsigned long flags;
179         int i;
180
181         printk(KERN_WARNING "ODEBUG: Out of memory. ODEBUG disabled\n");
182
183         for (i = 0; i < ODEBUG_HASH_SIZE; i++, db++) {
184                 spin_lock_irqsave(&db->lock, flags);
185                 hlist_move_list(&db->list, &freelist);
186                 spin_unlock_irqrestore(&db->lock, flags);
187
188                 /* Now free them */
189                 hlist_for_each_entry_safe(obj, node, tmp, &freelist, node) {
190                         hlist_del(&obj->node);
191                         free_object(obj);
192                 }
193         }
194 }
195
196 /*
197  * We use the pfn of the address for the hash. That way we can check
198  * for freed objects simply by checking the affected bucket.
199  */
200 static struct debug_bucket *get_bucket(unsigned long addr)
201 {
202         unsigned long hash;
203
204         hash = hash_long((addr >> ODEBUG_CHUNK_SHIFT), ODEBUG_HASH_BITS);
205         return &obj_hash[hash];
206 }
207
208 static void debug_print_object(struct debug_obj *obj, char *msg)
209 {
210         static int limit;
211
212         if (limit < 5 && obj->descr != descr_test) {
213                 limit++;
214                 WARN(1, KERN_ERR "ODEBUG: %s %s object type: %s\n", msg,
215                        obj_states[obj->state], obj->descr->name);
216         }
217         debug_objects_warnings++;
218 }
219
220 /*
221  * Try to repair the damage, so we have a better chance to get useful
222  * debug output.
223  */
224 static void
225 debug_object_fixup(int (*fixup)(void *addr, enum debug_obj_state state),
226                    void * addr, enum debug_obj_state state)
227 {
228         if (fixup)
229                 debug_objects_fixups += fixup(addr, state);
230 }
231
232 static void debug_object_is_on_stack(void *addr, int onstack)
233 {
234         int is_on_stack;
235         static int limit;
236
237         if (limit > 4)
238                 return;
239
240         is_on_stack = object_is_on_stack(addr);
241         if (is_on_stack == onstack)
242                 return;
243
244         limit++;
245         if (is_on_stack)
246                 printk(KERN_WARNING
247                        "ODEBUG: object is on stack, but not annotated\n");
248         else
249                 printk(KERN_WARNING
250                        "ODEBUG: object is not on stack, but annotated\n");
251         WARN_ON(1);
252 }
253
254 static void
255 __debug_object_init(void *addr, struct debug_obj_descr *descr, int onstack)
256 {
257         enum debug_obj_state state;
258         struct debug_bucket *db;
259         struct debug_obj *obj;
260         unsigned long flags;
261
262         fill_pool();
263
264         db = get_bucket((unsigned long) addr);
265
266         spin_lock_irqsave(&db->lock, flags);
267
268         obj = lookup_object(addr, db);
269         if (!obj) {
270                 obj = alloc_object(addr, db, descr);
271                 if (!obj) {
272                         debug_objects_enabled = 0;
273                         spin_unlock_irqrestore(&db->lock, flags);
274                         debug_objects_oom();
275                         return;
276                 }
277                 debug_object_is_on_stack(addr, onstack);
278         }
279
280         switch (obj->state) {
281         case ODEBUG_STATE_NONE:
282         case ODEBUG_STATE_INIT:
283         case ODEBUG_STATE_INACTIVE:
284                 obj->state = ODEBUG_STATE_INIT;
285                 break;
286
287         case ODEBUG_STATE_ACTIVE:
288                 debug_print_object(obj, "init");
289                 state = obj->state;
290                 spin_unlock_irqrestore(&db->lock, flags);
291                 debug_object_fixup(descr->fixup_init, addr, state);
292                 return;
293
294         case ODEBUG_STATE_DESTROYED:
295                 debug_print_object(obj, "init");
296                 break;
297         default:
298                 break;
299         }
300
301         spin_unlock_irqrestore(&db->lock, flags);
302 }
303
304 /**
305  * debug_object_init - debug checks when an object is initialized
306  * @addr:       address of the object
307  * @descr:      pointer to an object specific debug description structure
308  */
309 void debug_object_init(void *addr, struct debug_obj_descr *descr)
310 {
311         if (!debug_objects_enabled)
312                 return;
313
314         __debug_object_init(addr, descr, 0);
315 }
316
317 /**
318  * debug_object_init_on_stack - debug checks when an object on stack is
319  *                              initialized
320  * @addr:       address of the object
321  * @descr:      pointer to an object specific debug description structure
322  */
323 void debug_object_init_on_stack(void *addr, struct debug_obj_descr *descr)
324 {
325         if (!debug_objects_enabled)
326                 return;
327
328         __debug_object_init(addr, descr, 1);
329 }
330
331 /**
332  * debug_object_activate - debug checks when an object is activated
333  * @addr:       address of the object
334  * @descr:      pointer to an object specific debug description structure
335  */
336 void debug_object_activate(void *addr, struct debug_obj_descr *descr)
337 {
338         enum debug_obj_state state;
339         struct debug_bucket *db;
340         struct debug_obj *obj;
341         unsigned long flags;
342
343         if (!debug_objects_enabled)
344                 return;
345
346         db = get_bucket((unsigned long) addr);
347
348         spin_lock_irqsave(&db->lock, flags);
349
350         obj = lookup_object(addr, db);
351         if (obj) {
352                 switch (obj->state) {
353                 case ODEBUG_STATE_INIT:
354                 case ODEBUG_STATE_INACTIVE:
355                         obj->state = ODEBUG_STATE_ACTIVE;
356                         break;
357
358                 case ODEBUG_STATE_ACTIVE:
359                         debug_print_object(obj, "activate");
360                         state = obj->state;
361                         spin_unlock_irqrestore(&db->lock, flags);
362                         debug_object_fixup(descr->fixup_activate, addr, state);
363                         return;
364
365                 case ODEBUG_STATE_DESTROYED:
366                         debug_print_object(obj, "activate");
367                         break;
368                 default:
369                         break;
370                 }
371                 spin_unlock_irqrestore(&db->lock, flags);
372                 return;
373         }
374
375         spin_unlock_irqrestore(&db->lock, flags);
376         /*
377          * This happens when a static object is activated. We
378          * let the type specific code decide whether this is
379          * true or not.
380          */
381         debug_object_fixup(descr->fixup_activate, addr,
382                            ODEBUG_STATE_NOTAVAILABLE);
383 }
384
385 /**
386  * debug_object_deactivate - debug checks when an object is deactivated
387  * @addr:       address of the object
388  * @descr:      pointer to an object specific debug description structure
389  */
390 void debug_object_deactivate(void *addr, struct debug_obj_descr *descr)
391 {
392         struct debug_bucket *db;
393         struct debug_obj *obj;
394         unsigned long flags;
395
396         if (!debug_objects_enabled)
397                 return;
398
399         db = get_bucket((unsigned long) addr);
400
401         spin_lock_irqsave(&db->lock, flags);
402
403         obj = lookup_object(addr, db);
404         if (obj) {
405                 switch (obj->state) {
406                 case ODEBUG_STATE_INIT:
407                 case ODEBUG_STATE_INACTIVE:
408                 case ODEBUG_STATE_ACTIVE:
409                         obj->state = ODEBUG_STATE_INACTIVE;
410                         break;
411
412                 case ODEBUG_STATE_DESTROYED:
413                         debug_print_object(obj, "deactivate");
414                         break;
415                 default:
416                         break;
417                 }
418         } else {
419                 struct debug_obj o = { .object = addr,
420                                        .state = ODEBUG_STATE_NOTAVAILABLE,
421                                        .descr = descr };
422
423                 debug_print_object(&o, "deactivate");
424         }
425
426         spin_unlock_irqrestore(&db->lock, flags);
427 }
428
429 /**
430  * debug_object_destroy - debug checks when an object is destroyed
431  * @addr:       address of the object
432  * @descr:      pointer to an object specific debug description structure
433  */
434 void debug_object_destroy(void *addr, struct debug_obj_descr *descr)
435 {
436         enum debug_obj_state state;
437         struct debug_bucket *db;
438         struct debug_obj *obj;
439         unsigned long flags;
440
441         if (!debug_objects_enabled)
442                 return;
443
444         db = get_bucket((unsigned long) addr);
445
446         spin_lock_irqsave(&db->lock, flags);
447
448         obj = lookup_object(addr, db);
449         if (!obj)
450                 goto out_unlock;
451
452         switch (obj->state) {
453         case ODEBUG_STATE_NONE:
454         case ODEBUG_STATE_INIT:
455         case ODEBUG_STATE_INACTIVE:
456                 obj->state = ODEBUG_STATE_DESTROYED;
457                 break;
458         case ODEBUG_STATE_ACTIVE:
459                 debug_print_object(obj, "destroy");
460                 state = obj->state;
461                 spin_unlock_irqrestore(&db->lock, flags);
462                 debug_object_fixup(descr->fixup_destroy, addr, state);
463                 return;
464
465         case ODEBUG_STATE_DESTROYED:
466                 debug_print_object(obj, "destroy");
467                 break;
468         default:
469                 break;
470         }
471 out_unlock:
472         spin_unlock_irqrestore(&db->lock, flags);
473 }
474
475 /**
476  * debug_object_free - debug checks when an object is freed
477  * @addr:       address of the object
478  * @descr:      pointer to an object specific debug description structure
479  */
480 void debug_object_free(void *addr, struct debug_obj_descr *descr)
481 {
482         enum debug_obj_state state;
483         struct debug_bucket *db;
484         struct debug_obj *obj;
485         unsigned long flags;
486
487         if (!debug_objects_enabled)
488                 return;
489
490         db = get_bucket((unsigned long) addr);
491
492         spin_lock_irqsave(&db->lock, flags);
493
494         obj = lookup_object(addr, db);
495         if (!obj)
496                 goto out_unlock;
497
498         switch (obj->state) {
499         case ODEBUG_STATE_ACTIVE:
500                 debug_print_object(obj, "free");
501                 state = obj->state;
502                 spin_unlock_irqrestore(&db->lock, flags);
503                 debug_object_fixup(descr->fixup_free, addr, state);
504                 return;
505         default:
506                 hlist_del(&obj->node);
507                 spin_unlock_irqrestore(&db->lock, flags);
508                 free_object(obj);
509                 return;
510         }
511 out_unlock:
512         spin_unlock_irqrestore(&db->lock, flags);
513 }
514
515 #ifdef CONFIG_DEBUG_OBJECTS_FREE
516 static void __debug_check_no_obj_freed(const void *address, unsigned long size)
517 {
518         unsigned long flags, oaddr, saddr, eaddr, paddr, chunks;
519         struct hlist_node *node, *tmp;
520         HLIST_HEAD(freelist);
521         struct debug_obj_descr *descr;
522         enum debug_obj_state state;
523         struct debug_bucket *db;
524         struct debug_obj *obj;
525         int cnt;
526
527         saddr = (unsigned long) address;
528         eaddr = saddr + size;
529         paddr = saddr & ODEBUG_CHUNK_MASK;
530         chunks = ((eaddr - paddr) + (ODEBUG_CHUNK_SIZE - 1));
531         chunks >>= ODEBUG_CHUNK_SHIFT;
532
533         for (;chunks > 0; chunks--, paddr += ODEBUG_CHUNK_SIZE) {
534                 db = get_bucket(paddr);
535
536 repeat:
537                 cnt = 0;
538                 spin_lock_irqsave(&db->lock, flags);
539                 hlist_for_each_entry_safe(obj, node, tmp, &db->list, node) {
540                         cnt++;
541                         oaddr = (unsigned long) obj->object;
542                         if (oaddr < saddr || oaddr >= eaddr)
543                                 continue;
544
545                         switch (obj->state) {
546                         case ODEBUG_STATE_ACTIVE:
547                                 debug_print_object(obj, "free");
548                                 descr = obj->descr;
549                                 state = obj->state;
550                                 spin_unlock_irqrestore(&db->lock, flags);
551                                 debug_object_fixup(descr->fixup_free,
552                                                    (void *) oaddr, state);
553                                 goto repeat;
554                         default:
555                                 hlist_del(&obj->node);
556                                 hlist_add_head(&obj->node, &freelist);
557                                 break;
558                         }
559                 }
560                 spin_unlock_irqrestore(&db->lock, flags);
561
562                 /* Now free them */
563                 hlist_for_each_entry_safe(obj, node, tmp, &freelist, node) {
564                         hlist_del(&obj->node);
565                         free_object(obj);
566                 }
567
568                 if (cnt > debug_objects_maxchain)
569                         debug_objects_maxchain = cnt;
570         }
571 }
572
573 void debug_check_no_obj_freed(const void *address, unsigned long size)
574 {
575         if (debug_objects_enabled)
576                 __debug_check_no_obj_freed(address, size);
577 }
578 #endif
579
580 #ifdef CONFIG_DEBUG_FS
581
582 static int debug_stats_show(struct seq_file *m, void *v)
583 {
584         seq_printf(m, "max_chain     :%d\n", debug_objects_maxchain);
585         seq_printf(m, "warnings      :%d\n", debug_objects_warnings);
586         seq_printf(m, "fixups        :%d\n", debug_objects_fixups);
587         seq_printf(m, "pool_free     :%d\n", obj_pool_free);
588         seq_printf(m, "pool_min_free :%d\n", obj_pool_min_free);
589         seq_printf(m, "pool_used     :%d\n", obj_pool_used);
590         seq_printf(m, "pool_max_used :%d\n", obj_pool_max_used);
591         return 0;
592 }
593
594 static int debug_stats_open(struct inode *inode, struct file *filp)
595 {
596         return single_open(filp, debug_stats_show, NULL);
597 }
598
599 static const struct file_operations debug_stats_fops = {
600         .open           = debug_stats_open,
601         .read           = seq_read,
602         .llseek         = seq_lseek,
603         .release        = single_release,
604 };
605
606 static int __init debug_objects_init_debugfs(void)
607 {
608         struct dentry *dbgdir, *dbgstats;
609
610         if (!debug_objects_enabled)
611                 return 0;
612
613         dbgdir = debugfs_create_dir("debug_objects", NULL);
614         if (!dbgdir)
615                 return -ENOMEM;
616
617         dbgstats = debugfs_create_file("stats", 0444, dbgdir, NULL,
618                                        &debug_stats_fops);
619         if (!dbgstats)
620                 goto err;
621
622         return 0;
623
624 err:
625         debugfs_remove(dbgdir);
626
627         return -ENOMEM;
628 }
629 __initcall(debug_objects_init_debugfs);
630
631 #else
632 static inline void debug_objects_init_debugfs(void) { }
633 #endif
634
635 #ifdef CONFIG_DEBUG_OBJECTS_SELFTEST
636
637 /* Random data structure for the self test */
638 struct self_test {
639         unsigned long   dummy1[6];
640         int             static_init;
641         unsigned long   dummy2[3];
642 };
643
644 static __initdata struct debug_obj_descr descr_type_test;
645
646 /*
647  * fixup_init is called when:
648  * - an active object is initialized
649  */
650 static int __init fixup_init(void *addr, enum debug_obj_state state)
651 {
652         struct self_test *obj = addr;
653
654         switch (state) {
655         case ODEBUG_STATE_ACTIVE:
656                 debug_object_deactivate(obj, &descr_type_test);
657                 debug_object_init(obj, &descr_type_test);
658                 return 1;
659         default:
660                 return 0;
661         }
662 }
663
664 /*
665  * fixup_activate is called when:
666  * - an active object is activated
667  * - an unknown object is activated (might be a statically initialized object)
668  */
669 static int __init fixup_activate(void *addr, enum debug_obj_state state)
670 {
671         struct self_test *obj = addr;
672
673         switch (state) {
674         case ODEBUG_STATE_NOTAVAILABLE:
675                 if (obj->static_init == 1) {
676                         debug_object_init(obj, &descr_type_test);
677                         debug_object_activate(obj, &descr_type_test);
678                         /*
679                          * Real code should return 0 here ! This is
680                          * not a fixup of some bad behaviour. We
681                          * merily call the debug_init function to keep
682                          * track of the object.
683                          */
684                         return 1;
685                 } else {
686                         /* Real code needs to emit a warning here */
687                 }
688                 return 0;
689
690         case ODEBUG_STATE_ACTIVE:
691                 debug_object_deactivate(obj, &descr_type_test);
692                 debug_object_activate(obj, &descr_type_test);
693                 return 1;
694
695         default:
696                 return 0;
697         }
698 }
699
700 /*
701  * fixup_destroy is called when:
702  * - an active object is destroyed
703  */
704 static int __init fixup_destroy(void *addr, enum debug_obj_state state)
705 {
706         struct self_test *obj = addr;
707
708         switch (state) {
709         case ODEBUG_STATE_ACTIVE:
710                 debug_object_deactivate(obj, &descr_type_test);
711                 debug_object_destroy(obj, &descr_type_test);
712                 return 1;
713         default:
714                 return 0;
715         }
716 }
717
718 /*
719  * fixup_free is called when:
720  * - an active object is freed
721  */
722 static int __init fixup_free(void *addr, enum debug_obj_state state)
723 {
724         struct self_test *obj = addr;
725
726         switch (state) {
727         case ODEBUG_STATE_ACTIVE:
728                 debug_object_deactivate(obj, &descr_type_test);
729                 debug_object_free(obj, &descr_type_test);
730                 return 1;
731         default:
732                 return 0;
733         }
734 }
735
736 static int
737 check_results(void *addr, enum debug_obj_state state, int fixups, int warnings)
738 {
739         struct debug_bucket *db;
740         struct debug_obj *obj;
741         unsigned long flags;
742         int res = -EINVAL;
743
744         db = get_bucket((unsigned long) addr);
745
746         spin_lock_irqsave(&db->lock, flags);
747
748         obj = lookup_object(addr, db);
749         if (!obj && state != ODEBUG_STATE_NONE) {
750                 WARN(1, KERN_ERR "ODEBUG: selftest object not found\n");
751                 goto out;
752         }
753         if (obj && obj->state != state) {
754                 WARN(1, KERN_ERR "ODEBUG: selftest wrong state: %d != %d\n",
755                        obj->state, state);
756                 goto out;
757         }
758         if (fixups != debug_objects_fixups) {
759                 WARN(1, KERN_ERR "ODEBUG: selftest fixups failed %d != %d\n",
760                        fixups, debug_objects_fixups);
761                 goto out;
762         }
763         if (warnings != debug_objects_warnings) {
764                 WARN(1, KERN_ERR "ODEBUG: selftest warnings failed %d != %d\n",
765                        warnings, debug_objects_warnings);
766                 goto out;
767         }
768         res = 0;
769 out:
770         spin_unlock_irqrestore(&db->lock, flags);
771         if (res)
772                 debug_objects_enabled = 0;
773         return res;
774 }
775
776 static __initdata struct debug_obj_descr descr_type_test = {
777         .name                   = "selftest",
778         .fixup_init             = fixup_init,
779         .fixup_activate         = fixup_activate,
780         .fixup_destroy          = fixup_destroy,
781         .fixup_free             = fixup_free,
782 };
783
784 static __initdata struct self_test obj = { .static_init = 0 };
785
786 static void __init debug_objects_selftest(void)
787 {
788         int fixups, oldfixups, warnings, oldwarnings;
789         unsigned long flags;
790
791         local_irq_save(flags);
792
793         fixups = oldfixups = debug_objects_fixups;
794         warnings = oldwarnings = debug_objects_warnings;
795         descr_test = &descr_type_test;
796
797         debug_object_init(&obj, &descr_type_test);
798         if (check_results(&obj, ODEBUG_STATE_INIT, fixups, warnings))
799                 goto out;
800         debug_object_activate(&obj, &descr_type_test);
801         if (check_results(&obj, ODEBUG_STATE_ACTIVE, fixups, warnings))
802                 goto out;
803         debug_object_activate(&obj, &descr_type_test);
804         if (check_results(&obj, ODEBUG_STATE_ACTIVE, ++fixups, ++warnings))
805                 goto out;
806         debug_object_deactivate(&obj, &descr_type_test);
807         if (check_results(&obj, ODEBUG_STATE_INACTIVE, fixups, warnings))
808                 goto out;
809         debug_object_destroy(&obj, &descr_type_test);
810         if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, warnings))
811                 goto out;
812         debug_object_init(&obj, &descr_type_test);
813         if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, ++warnings))
814                 goto out;
815         debug_object_activate(&obj, &descr_type_test);
816         if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, ++warnings))
817                 goto out;
818         debug_object_deactivate(&obj, &descr_type_test);
819         if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, ++warnings))
820                 goto out;
821         debug_object_free(&obj, &descr_type_test);
822         if (check_results(&obj, ODEBUG_STATE_NONE, fixups, warnings))
823                 goto out;
824
825         obj.static_init = 1;
826         debug_object_activate(&obj, &descr_type_test);
827         if (check_results(&obj, ODEBUG_STATE_ACTIVE, ++fixups, warnings))
828                 goto out;
829         debug_object_init(&obj, &descr_type_test);
830         if (check_results(&obj, ODEBUG_STATE_INIT, ++fixups, ++warnings))
831                 goto out;
832         debug_object_free(&obj, &descr_type_test);
833         if (check_results(&obj, ODEBUG_STATE_NONE, fixups, warnings))
834                 goto out;
835
836 #ifdef CONFIG_DEBUG_OBJECTS_FREE
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_check_no_obj_freed(&obj, sizeof(obj));
844         if (check_results(&obj, ODEBUG_STATE_NONE, ++fixups, ++warnings))
845                 goto out;
846 #endif
847         printk(KERN_INFO "ODEBUG: selftest passed\n");
848
849 out:
850         debug_objects_fixups = oldfixups;
851         debug_objects_warnings = oldwarnings;
852         descr_test = NULL;
853
854         local_irq_restore(flags);
855 }
856 #else
857 static inline void debug_objects_selftest(void) { }
858 #endif
859
860 /*
861  * Called during early boot to initialize the hash buckets and link
862  * the static object pool objects into the poll list. After this call
863  * the object tracker is fully operational.
864  */
865 void __init debug_objects_early_init(void)
866 {
867         int i;
868
869         for (i = 0; i < ODEBUG_HASH_SIZE; i++)
870                 spin_lock_init(&obj_hash[i].lock);
871
872         for (i = 0; i < ODEBUG_POOL_SIZE; i++)
873                 hlist_add_head(&obj_static_pool[i].node, &obj_pool);
874 }
875
876 /*
877  * Called after the kmem_caches are functional to setup a dedicated
878  * cache pool, which has the SLAB_DEBUG_OBJECTS flag set. This flag
879  * prevents that the debug code is called on kmem_cache_free() for the
880  * debug tracker objects to avoid recursive calls.
881  */
882 void __init debug_objects_mem_init(void)
883 {
884         if (!debug_objects_enabled)
885                 return;
886
887         obj_cache = kmem_cache_create("debug_objects_cache",
888                                       sizeof (struct debug_obj), 0,
889                                       SLAB_DEBUG_OBJECTS, NULL);
890
891         if (!obj_cache)
892                 debug_objects_enabled = 0;
893         else
894                 debug_objects_selftest();
895 }