2 * Generic infrastructure for lifetime debugging of objects.
4 * Started by Thomas Gleixner
6 * Copyright (C) 2008, Thomas Gleixner <tglx@linutronix.de>
8 * For licencing details see kernel-base/COPYING
11 #define pr_fmt(fmt) "ODEBUG: " fmt
13 #include <linux/debugobjects.h>
14 #include <linux/interrupt.h>
15 #include <linux/sched.h>
16 #include <linux/seq_file.h>
17 #include <linux/debugfs.h>
18 #include <linux/slab.h>
19 #include <linux/hash.h>
21 #define ODEBUG_HASH_BITS 14
22 #define ODEBUG_HASH_SIZE (1 << ODEBUG_HASH_BITS)
24 #define ODEBUG_POOL_SIZE 512
25 #define ODEBUG_POOL_MIN_LEVEL 256
27 #define ODEBUG_CHUNK_SHIFT PAGE_SHIFT
28 #define ODEBUG_CHUNK_SIZE (1 << ODEBUG_CHUNK_SHIFT)
29 #define ODEBUG_CHUNK_MASK (~(ODEBUG_CHUNK_SIZE - 1))
32 struct hlist_head list;
36 static struct debug_bucket obj_hash[ODEBUG_HASH_SIZE];
38 static struct debug_obj obj_static_pool[ODEBUG_POOL_SIZE] __initdata;
40 static DEFINE_RAW_SPINLOCK(pool_lock);
42 static HLIST_HEAD(obj_pool);
44 static int obj_pool_min_free = ODEBUG_POOL_SIZE;
45 static int obj_pool_free = ODEBUG_POOL_SIZE;
46 static int obj_pool_used;
47 static int obj_pool_max_used;
48 static struct kmem_cache *obj_cache;
50 static int debug_objects_maxchain __read_mostly;
51 static int debug_objects_fixups __read_mostly;
52 static int debug_objects_warnings __read_mostly;
53 static int debug_objects_enabled __read_mostly
54 = CONFIG_DEBUG_OBJECTS_ENABLE_DEFAULT;
56 static struct debug_obj_descr *descr_test __read_mostly;
58 static void free_obj_work(struct work_struct *work);
59 static DECLARE_WORK(debug_obj_work, free_obj_work);
61 static int __init enable_object_debug(char *str)
63 debug_objects_enabled = 1;
67 static int __init disable_object_debug(char *str)
69 debug_objects_enabled = 0;
73 early_param("debug_objects", enable_object_debug);
74 early_param("no_debug_objects", disable_object_debug);
76 static const char *obj_states[ODEBUG_STATE_MAX] = {
77 [ODEBUG_STATE_NONE] = "none",
78 [ODEBUG_STATE_INIT] = "initialized",
79 [ODEBUG_STATE_INACTIVE] = "inactive",
80 [ODEBUG_STATE_ACTIVE] = "active",
81 [ODEBUG_STATE_DESTROYED] = "destroyed",
82 [ODEBUG_STATE_NOTAVAILABLE] = "not available",
85 static void fill_pool(void)
87 gfp_t gfp = GFP_ATOMIC | __GFP_NORETRY | __GFP_NOWARN;
88 struct debug_obj *new;
91 if (likely(obj_pool_free >= ODEBUG_POOL_MIN_LEVEL))
94 if (unlikely(!obj_cache))
97 while (obj_pool_free < ODEBUG_POOL_MIN_LEVEL) {
99 new = kmem_cache_zalloc(obj_cache, gfp);
103 raw_spin_lock_irqsave(&pool_lock, flags);
104 hlist_add_head(&new->node, &obj_pool);
106 raw_spin_unlock_irqrestore(&pool_lock, flags);
111 * Lookup an object in the hash bucket.
113 static struct debug_obj *lookup_object(void *addr, struct debug_bucket *b)
115 struct debug_obj *obj;
118 hlist_for_each_entry(obj, &b->list, node) {
120 if (obj->object == addr)
123 if (cnt > debug_objects_maxchain)
124 debug_objects_maxchain = cnt;
130 * Allocate a new object. If the pool is empty, switch off the debugger.
131 * Must be called with interrupts disabled.
133 static struct debug_obj *
134 alloc_object(void *addr, struct debug_bucket *b, struct debug_obj_descr *descr)
136 struct debug_obj *obj = NULL;
138 raw_spin_lock(&pool_lock);
139 if (obj_pool.first) {
140 obj = hlist_entry(obj_pool.first, typeof(*obj), node);
144 obj->state = ODEBUG_STATE_NONE;
146 hlist_del(&obj->node);
148 hlist_add_head(&obj->node, &b->list);
151 if (obj_pool_used > obj_pool_max_used)
152 obj_pool_max_used = obj_pool_used;
155 if (obj_pool_free < obj_pool_min_free)
156 obj_pool_min_free = obj_pool_free;
158 raw_spin_unlock(&pool_lock);
164 * workqueue function to free objects.
166 static void free_obj_work(struct work_struct *work)
168 struct debug_obj *obj;
171 raw_spin_lock_irqsave(&pool_lock, flags);
172 while (obj_pool_free > ODEBUG_POOL_SIZE) {
173 obj = hlist_entry(obj_pool.first, typeof(*obj), node);
174 hlist_del(&obj->node);
177 * We release pool_lock across kmem_cache_free() to
178 * avoid contention on pool_lock.
180 raw_spin_unlock_irqrestore(&pool_lock, flags);
181 kmem_cache_free(obj_cache, obj);
182 raw_spin_lock_irqsave(&pool_lock, flags);
184 raw_spin_unlock_irqrestore(&pool_lock, flags);
188 * Put the object back into the pool and schedule work to free objects
191 static void free_object(struct debug_obj *obj)
196 raw_spin_lock_irqsave(&pool_lock, flags);
198 * schedule work when the pool is filled and the cache is
201 if (obj_pool_free > ODEBUG_POOL_SIZE && obj_cache)
202 sched = keventd_up();
203 hlist_add_head(&obj->node, &obj_pool);
206 raw_spin_unlock_irqrestore(&pool_lock, flags);
208 schedule_work(&debug_obj_work);
212 * We run out of memory. That means we probably have tons of objects
215 static void debug_objects_oom(void)
217 struct debug_bucket *db = obj_hash;
218 struct hlist_node *tmp;
219 HLIST_HEAD(freelist);
220 struct debug_obj *obj;
224 pr_warn("Out of memory. ODEBUG disabled\n");
226 for (i = 0; i < ODEBUG_HASH_SIZE; i++, db++) {
227 raw_spin_lock_irqsave(&db->lock, flags);
228 hlist_move_list(&db->list, &freelist);
229 raw_spin_unlock_irqrestore(&db->lock, flags);
232 hlist_for_each_entry_safe(obj, tmp, &freelist, node) {
233 hlist_del(&obj->node);
240 * We use the pfn of the address for the hash. That way we can check
241 * for freed objects simply by checking the affected bucket.
243 static struct debug_bucket *get_bucket(unsigned long addr)
247 hash = hash_long((addr >> ODEBUG_CHUNK_SHIFT), ODEBUG_HASH_BITS);
248 return &obj_hash[hash];
251 static void debug_print_object(struct debug_obj *obj, char *msg)
253 struct debug_obj_descr *descr = obj->descr;
256 if (limit < 5 && descr != descr_test) {
257 void *hint = descr->debug_hint ?
258 descr->debug_hint(obj->object) : NULL;
260 WARN(1, KERN_ERR "ODEBUG: %s %s (active state %u) "
261 "object type: %s hint: %pS\n",
262 msg, obj_states[obj->state], obj->astate,
265 debug_objects_warnings++;
269 * Try to repair the damage, so we have a better chance to get useful
273 debug_object_fixup(int (*fixup)(void *addr, enum debug_obj_state state),
274 void * addr, enum debug_obj_state state)
279 fixed = fixup(addr, state);
280 debug_objects_fixups += fixed;
284 static void debug_object_is_on_stack(void *addr, int onstack)
292 is_on_stack = object_is_on_stack(addr);
293 if (is_on_stack == onstack)
298 pr_warn("object is on stack, but not annotated\n");
300 pr_warn("object is not on stack, but annotated\n");
305 __debug_object_init(void *addr, struct debug_obj_descr *descr, int onstack)
307 enum debug_obj_state state;
308 struct debug_bucket *db;
309 struct debug_obj *obj;
314 db = get_bucket((unsigned long) addr);
316 raw_spin_lock_irqsave(&db->lock, flags);
318 obj = lookup_object(addr, db);
320 obj = alloc_object(addr, db, descr);
322 debug_objects_enabled = 0;
323 raw_spin_unlock_irqrestore(&db->lock, flags);
327 debug_object_is_on_stack(addr, onstack);
330 switch (obj->state) {
331 case ODEBUG_STATE_NONE:
332 case ODEBUG_STATE_INIT:
333 case ODEBUG_STATE_INACTIVE:
334 obj->state = ODEBUG_STATE_INIT;
337 case ODEBUG_STATE_ACTIVE:
338 debug_print_object(obj, "init");
340 raw_spin_unlock_irqrestore(&db->lock, flags);
341 debug_object_fixup(descr->fixup_init, addr, state);
344 case ODEBUG_STATE_DESTROYED:
345 debug_print_object(obj, "init");
351 raw_spin_unlock_irqrestore(&db->lock, flags);
355 * debug_object_init - debug checks when an object is initialized
356 * @addr: address of the object
357 * @descr: pointer to an object specific debug description structure
359 void debug_object_init(void *addr, struct debug_obj_descr *descr)
361 if (!debug_objects_enabled)
364 __debug_object_init(addr, descr, 0);
368 * debug_object_init_on_stack - debug checks when an object on stack is
370 * @addr: address of the object
371 * @descr: pointer to an object specific debug description structure
373 void debug_object_init_on_stack(void *addr, struct debug_obj_descr *descr)
375 if (!debug_objects_enabled)
378 __debug_object_init(addr, descr, 1);
382 * debug_object_activate - debug checks when an object is activated
383 * @addr: address of the object
384 * @descr: pointer to an object specific debug description structure
385 * Returns 0 for success, -EINVAL for check failed.
387 int debug_object_activate(void *addr, struct debug_obj_descr *descr)
389 enum debug_obj_state state;
390 struct debug_bucket *db;
391 struct debug_obj *obj;
394 struct debug_obj o = { .object = addr,
395 .state = ODEBUG_STATE_NOTAVAILABLE,
398 if (!debug_objects_enabled)
401 db = get_bucket((unsigned long) addr);
403 raw_spin_lock_irqsave(&db->lock, flags);
405 obj = lookup_object(addr, db);
407 switch (obj->state) {
408 case ODEBUG_STATE_INIT:
409 case ODEBUG_STATE_INACTIVE:
410 obj->state = ODEBUG_STATE_ACTIVE;
414 case ODEBUG_STATE_ACTIVE:
415 debug_print_object(obj, "activate");
417 raw_spin_unlock_irqrestore(&db->lock, flags);
418 ret = debug_object_fixup(descr->fixup_activate, addr, state);
419 return ret ? -EINVAL : 0;
421 case ODEBUG_STATE_DESTROYED:
422 debug_print_object(obj, "activate");
429 raw_spin_unlock_irqrestore(&db->lock, flags);
433 raw_spin_unlock_irqrestore(&db->lock, flags);
435 * This happens when a static object is activated. We
436 * let the type specific code decide whether this is
439 if (debug_object_fixup(descr->fixup_activate, addr,
440 ODEBUG_STATE_NOTAVAILABLE)) {
441 debug_print_object(&o, "activate");
448 * debug_object_deactivate - debug checks when an object is deactivated
449 * @addr: address of the object
450 * @descr: pointer to an object specific debug description structure
452 void debug_object_deactivate(void *addr, struct debug_obj_descr *descr)
454 struct debug_bucket *db;
455 struct debug_obj *obj;
458 if (!debug_objects_enabled)
461 db = get_bucket((unsigned long) addr);
463 raw_spin_lock_irqsave(&db->lock, flags);
465 obj = lookup_object(addr, db);
467 switch (obj->state) {
468 case ODEBUG_STATE_INIT:
469 case ODEBUG_STATE_INACTIVE:
470 case ODEBUG_STATE_ACTIVE:
472 obj->state = ODEBUG_STATE_INACTIVE;
474 debug_print_object(obj, "deactivate");
477 case ODEBUG_STATE_DESTROYED:
478 debug_print_object(obj, "deactivate");
484 struct debug_obj o = { .object = addr,
485 .state = ODEBUG_STATE_NOTAVAILABLE,
488 debug_print_object(&o, "deactivate");
491 raw_spin_unlock_irqrestore(&db->lock, flags);
495 * debug_object_destroy - debug checks when an object is destroyed
496 * @addr: address of the object
497 * @descr: pointer to an object specific debug description structure
499 void debug_object_destroy(void *addr, struct debug_obj_descr *descr)
501 enum debug_obj_state state;
502 struct debug_bucket *db;
503 struct debug_obj *obj;
506 if (!debug_objects_enabled)
509 db = get_bucket((unsigned long) addr);
511 raw_spin_lock_irqsave(&db->lock, flags);
513 obj = lookup_object(addr, db);
517 switch (obj->state) {
518 case ODEBUG_STATE_NONE:
519 case ODEBUG_STATE_INIT:
520 case ODEBUG_STATE_INACTIVE:
521 obj->state = ODEBUG_STATE_DESTROYED;
523 case ODEBUG_STATE_ACTIVE:
524 debug_print_object(obj, "destroy");
526 raw_spin_unlock_irqrestore(&db->lock, flags);
527 debug_object_fixup(descr->fixup_destroy, addr, state);
530 case ODEBUG_STATE_DESTROYED:
531 debug_print_object(obj, "destroy");
537 raw_spin_unlock_irqrestore(&db->lock, flags);
541 * debug_object_free - debug checks when an object is freed
542 * @addr: address of the object
543 * @descr: pointer to an object specific debug description structure
545 void debug_object_free(void *addr, struct debug_obj_descr *descr)
547 enum debug_obj_state state;
548 struct debug_bucket *db;
549 struct debug_obj *obj;
552 if (!debug_objects_enabled)
555 db = get_bucket((unsigned long) addr);
557 raw_spin_lock_irqsave(&db->lock, flags);
559 obj = lookup_object(addr, db);
563 switch (obj->state) {
564 case ODEBUG_STATE_ACTIVE:
565 debug_print_object(obj, "free");
567 raw_spin_unlock_irqrestore(&db->lock, flags);
568 debug_object_fixup(descr->fixup_free, addr, state);
571 hlist_del(&obj->node);
572 raw_spin_unlock_irqrestore(&db->lock, flags);
577 raw_spin_unlock_irqrestore(&db->lock, flags);
581 * debug_object_assert_init - debug checks when object should be init-ed
582 * @addr: address of the object
583 * @descr: pointer to an object specific debug description structure
585 void debug_object_assert_init(void *addr, struct debug_obj_descr *descr)
587 struct debug_bucket *db;
588 struct debug_obj *obj;
591 if (!debug_objects_enabled)
594 db = get_bucket((unsigned long) addr);
596 raw_spin_lock_irqsave(&db->lock, flags);
598 obj = lookup_object(addr, db);
600 struct debug_obj o = { .object = addr,
601 .state = ODEBUG_STATE_NOTAVAILABLE,
604 raw_spin_unlock_irqrestore(&db->lock, flags);
606 * Maybe the object is static. Let the type specific
607 * code decide what to do.
609 if (debug_object_fixup(descr->fixup_assert_init, addr,
610 ODEBUG_STATE_NOTAVAILABLE))
611 debug_print_object(&o, "assert_init");
615 raw_spin_unlock_irqrestore(&db->lock, flags);
619 * debug_object_active_state - debug checks object usage state machine
620 * @addr: address of the object
621 * @descr: pointer to an object specific debug description structure
622 * @expect: expected state
623 * @next: state to move to if expected state is found
626 debug_object_active_state(void *addr, struct debug_obj_descr *descr,
627 unsigned int expect, unsigned int next)
629 struct debug_bucket *db;
630 struct debug_obj *obj;
633 if (!debug_objects_enabled)
636 db = get_bucket((unsigned long) addr);
638 raw_spin_lock_irqsave(&db->lock, flags);
640 obj = lookup_object(addr, db);
642 switch (obj->state) {
643 case ODEBUG_STATE_ACTIVE:
644 if (obj->astate == expect)
647 debug_print_object(obj, "active_state");
651 debug_print_object(obj, "active_state");
655 struct debug_obj o = { .object = addr,
656 .state = ODEBUG_STATE_NOTAVAILABLE,
659 debug_print_object(&o, "active_state");
662 raw_spin_unlock_irqrestore(&db->lock, flags);
665 #ifdef CONFIG_DEBUG_OBJECTS_FREE
666 static void __debug_check_no_obj_freed(const void *address, unsigned long size)
668 unsigned long flags, oaddr, saddr, eaddr, paddr, chunks;
669 struct hlist_node *tmp;
670 HLIST_HEAD(freelist);
671 struct debug_obj_descr *descr;
672 enum debug_obj_state state;
673 struct debug_bucket *db;
674 struct debug_obj *obj;
677 saddr = (unsigned long) address;
678 eaddr = saddr + size;
679 paddr = saddr & ODEBUG_CHUNK_MASK;
680 chunks = ((eaddr - paddr) + (ODEBUG_CHUNK_SIZE - 1));
681 chunks >>= ODEBUG_CHUNK_SHIFT;
683 for (;chunks > 0; chunks--, paddr += ODEBUG_CHUNK_SIZE) {
684 db = get_bucket(paddr);
688 raw_spin_lock_irqsave(&db->lock, flags);
689 hlist_for_each_entry_safe(obj, tmp, &db->list, node) {
691 oaddr = (unsigned long) obj->object;
692 if (oaddr < saddr || oaddr >= eaddr)
695 switch (obj->state) {
696 case ODEBUG_STATE_ACTIVE:
697 debug_print_object(obj, "free");
700 raw_spin_unlock_irqrestore(&db->lock, flags);
701 debug_object_fixup(descr->fixup_free,
702 (void *) oaddr, state);
705 hlist_del(&obj->node);
706 hlist_add_head(&obj->node, &freelist);
710 raw_spin_unlock_irqrestore(&db->lock, flags);
713 hlist_for_each_entry_safe(obj, tmp, &freelist, node) {
714 hlist_del(&obj->node);
718 if (cnt > debug_objects_maxchain)
719 debug_objects_maxchain = cnt;
723 void debug_check_no_obj_freed(const void *address, unsigned long size)
725 if (debug_objects_enabled)
726 __debug_check_no_obj_freed(address, size);
730 #ifdef CONFIG_DEBUG_FS
732 static int debug_stats_show(struct seq_file *m, void *v)
734 seq_printf(m, "max_chain :%d\n", debug_objects_maxchain);
735 seq_printf(m, "warnings :%d\n", debug_objects_warnings);
736 seq_printf(m, "fixups :%d\n", debug_objects_fixups);
737 seq_printf(m, "pool_free :%d\n", obj_pool_free);
738 seq_printf(m, "pool_min_free :%d\n", obj_pool_min_free);
739 seq_printf(m, "pool_used :%d\n", obj_pool_used);
740 seq_printf(m, "pool_max_used :%d\n", obj_pool_max_used);
744 static int debug_stats_open(struct inode *inode, struct file *filp)
746 return single_open(filp, debug_stats_show, NULL);
749 static const struct file_operations debug_stats_fops = {
750 .open = debug_stats_open,
753 .release = single_release,
756 static int __init debug_objects_init_debugfs(void)
758 struct dentry *dbgdir, *dbgstats;
760 if (!debug_objects_enabled)
763 dbgdir = debugfs_create_dir("debug_objects", NULL);
767 dbgstats = debugfs_create_file("stats", 0444, dbgdir, NULL,
775 debugfs_remove(dbgdir);
779 __initcall(debug_objects_init_debugfs);
782 static inline void debug_objects_init_debugfs(void) { }
785 #ifdef CONFIG_DEBUG_OBJECTS_SELFTEST
787 /* Random data structure for the self test */
789 unsigned long dummy1[6];
791 unsigned long dummy2[3];
794 static __initdata struct debug_obj_descr descr_type_test;
797 * fixup_init is called when:
798 * - an active object is initialized
800 static int __init fixup_init(void *addr, enum debug_obj_state state)
802 struct self_test *obj = addr;
805 case ODEBUG_STATE_ACTIVE:
806 debug_object_deactivate(obj, &descr_type_test);
807 debug_object_init(obj, &descr_type_test);
815 * fixup_activate is called when:
816 * - an active object is activated
817 * - an unknown object is activated (might be a statically initialized object)
819 static int __init fixup_activate(void *addr, enum debug_obj_state state)
821 struct self_test *obj = addr;
824 case ODEBUG_STATE_NOTAVAILABLE:
825 if (obj->static_init == 1) {
826 debug_object_init(obj, &descr_type_test);
827 debug_object_activate(obj, &descr_type_test);
832 case ODEBUG_STATE_ACTIVE:
833 debug_object_deactivate(obj, &descr_type_test);
834 debug_object_activate(obj, &descr_type_test);
843 * fixup_destroy is called when:
844 * - an active object is destroyed
846 static int __init fixup_destroy(void *addr, enum debug_obj_state state)
848 struct self_test *obj = addr;
851 case ODEBUG_STATE_ACTIVE:
852 debug_object_deactivate(obj, &descr_type_test);
853 debug_object_destroy(obj, &descr_type_test);
861 * fixup_free is called when:
862 * - an active object is freed
864 static int __init fixup_free(void *addr, enum debug_obj_state state)
866 struct self_test *obj = addr;
869 case ODEBUG_STATE_ACTIVE:
870 debug_object_deactivate(obj, &descr_type_test);
871 debug_object_free(obj, &descr_type_test);
879 check_results(void *addr, enum debug_obj_state state, int fixups, int warnings)
881 struct debug_bucket *db;
882 struct debug_obj *obj;
886 db = get_bucket((unsigned long) addr);
888 raw_spin_lock_irqsave(&db->lock, flags);
890 obj = lookup_object(addr, db);
891 if (!obj && state != ODEBUG_STATE_NONE) {
892 WARN(1, KERN_ERR "ODEBUG: selftest object not found\n");
895 if (obj && obj->state != state) {
896 WARN(1, KERN_ERR "ODEBUG: selftest wrong state: %d != %d\n",
900 if (fixups != debug_objects_fixups) {
901 WARN(1, KERN_ERR "ODEBUG: selftest fixups failed %d != %d\n",
902 fixups, debug_objects_fixups);
905 if (warnings != debug_objects_warnings) {
906 WARN(1, KERN_ERR "ODEBUG: selftest warnings failed %d != %d\n",
907 warnings, debug_objects_warnings);
912 raw_spin_unlock_irqrestore(&db->lock, flags);
914 debug_objects_enabled = 0;
918 static __initdata struct debug_obj_descr descr_type_test = {
920 .fixup_init = fixup_init,
921 .fixup_activate = fixup_activate,
922 .fixup_destroy = fixup_destroy,
923 .fixup_free = fixup_free,
926 static __initdata struct self_test obj = { .static_init = 0 };
928 static void __init debug_objects_selftest(void)
930 int fixups, oldfixups, warnings, oldwarnings;
933 local_irq_save(flags);
935 fixups = oldfixups = debug_objects_fixups;
936 warnings = oldwarnings = debug_objects_warnings;
937 descr_test = &descr_type_test;
939 debug_object_init(&obj, &descr_type_test);
940 if (check_results(&obj, ODEBUG_STATE_INIT, fixups, warnings))
942 debug_object_activate(&obj, &descr_type_test);
943 if (check_results(&obj, ODEBUG_STATE_ACTIVE, fixups, warnings))
945 debug_object_activate(&obj, &descr_type_test);
946 if (check_results(&obj, ODEBUG_STATE_ACTIVE, ++fixups, ++warnings))
948 debug_object_deactivate(&obj, &descr_type_test);
949 if (check_results(&obj, ODEBUG_STATE_INACTIVE, fixups, warnings))
951 debug_object_destroy(&obj, &descr_type_test);
952 if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, warnings))
954 debug_object_init(&obj, &descr_type_test);
955 if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, ++warnings))
957 debug_object_activate(&obj, &descr_type_test);
958 if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, ++warnings))
960 debug_object_deactivate(&obj, &descr_type_test);
961 if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, ++warnings))
963 debug_object_free(&obj, &descr_type_test);
964 if (check_results(&obj, ODEBUG_STATE_NONE, fixups, warnings))
968 debug_object_activate(&obj, &descr_type_test);
969 if (check_results(&obj, ODEBUG_STATE_ACTIVE, fixups, warnings))
971 debug_object_init(&obj, &descr_type_test);
972 if (check_results(&obj, ODEBUG_STATE_INIT, ++fixups, ++warnings))
974 debug_object_free(&obj, &descr_type_test);
975 if (check_results(&obj, ODEBUG_STATE_NONE, fixups, warnings))
978 #ifdef CONFIG_DEBUG_OBJECTS_FREE
979 debug_object_init(&obj, &descr_type_test);
980 if (check_results(&obj, ODEBUG_STATE_INIT, fixups, warnings))
982 debug_object_activate(&obj, &descr_type_test);
983 if (check_results(&obj, ODEBUG_STATE_ACTIVE, fixups, warnings))
985 __debug_check_no_obj_freed(&obj, sizeof(obj));
986 if (check_results(&obj, ODEBUG_STATE_NONE, ++fixups, ++warnings))
989 pr_info("selftest passed\n");
992 debug_objects_fixups = oldfixups;
993 debug_objects_warnings = oldwarnings;
996 local_irq_restore(flags);
999 static inline void debug_objects_selftest(void) { }
1003 * Called during early boot to initialize the hash buckets and link
1004 * the static object pool objects into the poll list. After this call
1005 * the object tracker is fully operational.
1007 void __init debug_objects_early_init(void)
1011 for (i = 0; i < ODEBUG_HASH_SIZE; i++)
1012 raw_spin_lock_init(&obj_hash[i].lock);
1014 for (i = 0; i < ODEBUG_POOL_SIZE; i++)
1015 hlist_add_head(&obj_static_pool[i].node, &obj_pool);
1019 * Convert the statically allocated objects to dynamic ones:
1021 static int __init debug_objects_replace_static_objects(void)
1023 struct debug_bucket *db = obj_hash;
1024 struct hlist_node *tmp;
1025 struct debug_obj *obj, *new;
1026 HLIST_HEAD(objects);
1029 for (i = 0; i < ODEBUG_POOL_SIZE; i++) {
1030 obj = kmem_cache_zalloc(obj_cache, GFP_KERNEL);
1033 hlist_add_head(&obj->node, &objects);
1037 * When debug_objects_mem_init() is called we know that only
1038 * one CPU is up, so disabling interrupts is enough
1039 * protection. This avoids the lockdep hell of lock ordering.
1041 local_irq_disable();
1043 /* Remove the statically allocated objects from the pool */
1044 hlist_for_each_entry_safe(obj, tmp, &obj_pool, node)
1045 hlist_del(&obj->node);
1046 /* Move the allocated objects to the pool */
1047 hlist_move_list(&objects, &obj_pool);
1049 /* Replace the active object references */
1050 for (i = 0; i < ODEBUG_HASH_SIZE; i++, db++) {
1051 hlist_move_list(&db->list, &objects);
1053 hlist_for_each_entry(obj, &objects, node) {
1054 new = hlist_entry(obj_pool.first, typeof(*obj), node);
1055 hlist_del(&new->node);
1056 /* copy object data */
1058 hlist_add_head(&new->node, &db->list);
1064 pr_debug("%d of %d active objects replaced\n",
1065 cnt, obj_pool_used);
1068 hlist_for_each_entry_safe(obj, tmp, &objects, node) {
1069 hlist_del(&obj->node);
1070 kmem_cache_free(obj_cache, obj);
1076 * Called after the kmem_caches are functional to setup a dedicated
1077 * cache pool, which has the SLAB_DEBUG_OBJECTS flag set. This flag
1078 * prevents that the debug code is called on kmem_cache_free() for the
1079 * debug tracker objects to avoid recursive calls.
1081 void __init debug_objects_mem_init(void)
1083 if (!debug_objects_enabled)
1086 obj_cache = kmem_cache_create("debug_objects_cache",
1087 sizeof (struct debug_obj), 0,
1088 SLAB_DEBUG_OBJECTS, NULL);
1090 if (!obj_cache || debug_objects_replace_static_objects()) {
1091 debug_objects_enabled = 0;
1093 kmem_cache_destroy(obj_cache);
1094 pr_warn("out of memory.\n");
1096 debug_objects_selftest();