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 1024
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(bool (*fixup)(void *addr, enum debug_obj_state state),
274 void * addr, enum debug_obj_state state)
276 if (fixup && fixup(addr, state)) {
277 debug_objects_fixups++;
283 static void debug_object_is_on_stack(void *addr, int onstack)
291 is_on_stack = object_is_on_stack(addr);
292 if (is_on_stack == onstack)
297 pr_warn("object is on stack, but not annotated\n");
299 pr_warn("object is not on stack, but annotated\n");
304 __debug_object_init(void *addr, struct debug_obj_descr *descr, int onstack)
306 enum debug_obj_state state;
307 struct debug_bucket *db;
308 struct debug_obj *obj;
313 db = get_bucket((unsigned long) addr);
315 raw_spin_lock_irqsave(&db->lock, flags);
317 obj = lookup_object(addr, db);
319 obj = alloc_object(addr, db, descr);
321 debug_objects_enabled = 0;
322 raw_spin_unlock_irqrestore(&db->lock, flags);
326 debug_object_is_on_stack(addr, onstack);
329 switch (obj->state) {
330 case ODEBUG_STATE_NONE:
331 case ODEBUG_STATE_INIT:
332 case ODEBUG_STATE_INACTIVE:
333 obj->state = ODEBUG_STATE_INIT;
336 case ODEBUG_STATE_ACTIVE:
337 debug_print_object(obj, "init");
339 raw_spin_unlock_irqrestore(&db->lock, flags);
340 debug_object_fixup(descr->fixup_init, addr, state);
343 case ODEBUG_STATE_DESTROYED:
344 debug_print_object(obj, "init");
350 raw_spin_unlock_irqrestore(&db->lock, flags);
354 * debug_object_init - debug checks when an object is initialized
355 * @addr: address of the object
356 * @descr: pointer to an object specific debug description structure
358 void debug_object_init(void *addr, struct debug_obj_descr *descr)
360 if (!debug_objects_enabled)
363 __debug_object_init(addr, descr, 0);
367 * debug_object_init_on_stack - debug checks when an object on stack is
369 * @addr: address of the object
370 * @descr: pointer to an object specific debug description structure
372 void debug_object_init_on_stack(void *addr, struct debug_obj_descr *descr)
374 if (!debug_objects_enabled)
377 __debug_object_init(addr, descr, 1);
381 * debug_object_activate - debug checks when an object is activated
382 * @addr: address of the object
383 * @descr: pointer to an object specific debug description structure
384 * Returns 0 for success, -EINVAL for check failed.
386 int debug_object_activate(void *addr, struct debug_obj_descr *descr)
388 enum debug_obj_state state;
389 struct debug_bucket *db;
390 struct debug_obj *obj;
393 struct debug_obj o = { .object = addr,
394 .state = ODEBUG_STATE_NOTAVAILABLE,
397 if (!debug_objects_enabled)
400 db = get_bucket((unsigned long) addr);
402 raw_spin_lock_irqsave(&db->lock, flags);
404 obj = lookup_object(addr, db);
406 switch (obj->state) {
407 case ODEBUG_STATE_INIT:
408 case ODEBUG_STATE_INACTIVE:
409 obj->state = ODEBUG_STATE_ACTIVE;
413 case ODEBUG_STATE_ACTIVE:
414 debug_print_object(obj, "activate");
416 raw_spin_unlock_irqrestore(&db->lock, flags);
417 ret = debug_object_fixup(descr->fixup_activate, addr, state);
418 return ret ? -EINVAL : 0;
420 case ODEBUG_STATE_DESTROYED:
421 debug_print_object(obj, "activate");
428 raw_spin_unlock_irqrestore(&db->lock, flags);
432 raw_spin_unlock_irqrestore(&db->lock, flags);
434 * This happens when a static object is activated. We
435 * let the type specific code decide whether this is
438 if (debug_object_fixup(descr->fixup_activate, addr,
439 ODEBUG_STATE_NOTAVAILABLE)) {
440 debug_print_object(&o, "activate");
447 * debug_object_deactivate - debug checks when an object is deactivated
448 * @addr: address of the object
449 * @descr: pointer to an object specific debug description structure
451 void debug_object_deactivate(void *addr, struct debug_obj_descr *descr)
453 struct debug_bucket *db;
454 struct debug_obj *obj;
457 if (!debug_objects_enabled)
460 db = get_bucket((unsigned long) addr);
462 raw_spin_lock_irqsave(&db->lock, flags);
464 obj = lookup_object(addr, db);
466 switch (obj->state) {
467 case ODEBUG_STATE_INIT:
468 case ODEBUG_STATE_INACTIVE:
469 case ODEBUG_STATE_ACTIVE:
471 obj->state = ODEBUG_STATE_INACTIVE;
473 debug_print_object(obj, "deactivate");
476 case ODEBUG_STATE_DESTROYED:
477 debug_print_object(obj, "deactivate");
483 struct debug_obj o = { .object = addr,
484 .state = ODEBUG_STATE_NOTAVAILABLE,
487 debug_print_object(&o, "deactivate");
490 raw_spin_unlock_irqrestore(&db->lock, flags);
494 * debug_object_destroy - debug checks when an object is destroyed
495 * @addr: address of the object
496 * @descr: pointer to an object specific debug description structure
498 void debug_object_destroy(void *addr, struct debug_obj_descr *descr)
500 enum debug_obj_state state;
501 struct debug_bucket *db;
502 struct debug_obj *obj;
505 if (!debug_objects_enabled)
508 db = get_bucket((unsigned long) addr);
510 raw_spin_lock_irqsave(&db->lock, flags);
512 obj = lookup_object(addr, db);
516 switch (obj->state) {
517 case ODEBUG_STATE_NONE:
518 case ODEBUG_STATE_INIT:
519 case ODEBUG_STATE_INACTIVE:
520 obj->state = ODEBUG_STATE_DESTROYED;
522 case ODEBUG_STATE_ACTIVE:
523 debug_print_object(obj, "destroy");
525 raw_spin_unlock_irqrestore(&db->lock, flags);
526 debug_object_fixup(descr->fixup_destroy, addr, state);
529 case ODEBUG_STATE_DESTROYED:
530 debug_print_object(obj, "destroy");
536 raw_spin_unlock_irqrestore(&db->lock, flags);
540 * debug_object_free - debug checks when an object is freed
541 * @addr: address of the object
542 * @descr: pointer to an object specific debug description structure
544 void debug_object_free(void *addr, struct debug_obj_descr *descr)
546 enum debug_obj_state state;
547 struct debug_bucket *db;
548 struct debug_obj *obj;
551 if (!debug_objects_enabled)
554 db = get_bucket((unsigned long) addr);
556 raw_spin_lock_irqsave(&db->lock, flags);
558 obj = lookup_object(addr, db);
562 switch (obj->state) {
563 case ODEBUG_STATE_ACTIVE:
564 debug_print_object(obj, "free");
566 raw_spin_unlock_irqrestore(&db->lock, flags);
567 debug_object_fixup(descr->fixup_free, addr, state);
570 hlist_del(&obj->node);
571 raw_spin_unlock_irqrestore(&db->lock, flags);
576 raw_spin_unlock_irqrestore(&db->lock, flags);
580 * debug_object_assert_init - debug checks when object should be init-ed
581 * @addr: address of the object
582 * @descr: pointer to an object specific debug description structure
584 void debug_object_assert_init(void *addr, struct debug_obj_descr *descr)
586 struct debug_bucket *db;
587 struct debug_obj *obj;
590 if (!debug_objects_enabled)
593 db = get_bucket((unsigned long) addr);
595 raw_spin_lock_irqsave(&db->lock, flags);
597 obj = lookup_object(addr, db);
599 struct debug_obj o = { .object = addr,
600 .state = ODEBUG_STATE_NOTAVAILABLE,
603 raw_spin_unlock_irqrestore(&db->lock, flags);
605 * Maybe the object is static. Let the type specific
606 * code decide what to do.
608 if (debug_object_fixup(descr->fixup_assert_init, addr,
609 ODEBUG_STATE_NOTAVAILABLE))
610 debug_print_object(&o, "assert_init");
614 raw_spin_unlock_irqrestore(&db->lock, flags);
618 * debug_object_active_state - debug checks object usage state machine
619 * @addr: address of the object
620 * @descr: pointer to an object specific debug description structure
621 * @expect: expected state
622 * @next: state to move to if expected state is found
625 debug_object_active_state(void *addr, struct debug_obj_descr *descr,
626 unsigned int expect, unsigned int next)
628 struct debug_bucket *db;
629 struct debug_obj *obj;
632 if (!debug_objects_enabled)
635 db = get_bucket((unsigned long) addr);
637 raw_spin_lock_irqsave(&db->lock, flags);
639 obj = lookup_object(addr, db);
641 switch (obj->state) {
642 case ODEBUG_STATE_ACTIVE:
643 if (obj->astate == expect)
646 debug_print_object(obj, "active_state");
650 debug_print_object(obj, "active_state");
654 struct debug_obj o = { .object = addr,
655 .state = ODEBUG_STATE_NOTAVAILABLE,
658 debug_print_object(&o, "active_state");
661 raw_spin_unlock_irqrestore(&db->lock, flags);
664 #ifdef CONFIG_DEBUG_OBJECTS_FREE
665 static void __debug_check_no_obj_freed(const void *address, unsigned long size)
667 unsigned long flags, oaddr, saddr, eaddr, paddr, chunks;
668 struct hlist_node *tmp;
669 HLIST_HEAD(freelist);
670 struct debug_obj_descr *descr;
671 enum debug_obj_state state;
672 struct debug_bucket *db;
673 struct debug_obj *obj;
676 saddr = (unsigned long) address;
677 eaddr = saddr + size;
678 paddr = saddr & ODEBUG_CHUNK_MASK;
679 chunks = ((eaddr - paddr) + (ODEBUG_CHUNK_SIZE - 1));
680 chunks >>= ODEBUG_CHUNK_SHIFT;
682 for (;chunks > 0; chunks--, paddr += ODEBUG_CHUNK_SIZE) {
683 db = get_bucket(paddr);
687 raw_spin_lock_irqsave(&db->lock, flags);
688 hlist_for_each_entry_safe(obj, tmp, &db->list, node) {
690 oaddr = (unsigned long) obj->object;
691 if (oaddr < saddr || oaddr >= eaddr)
694 switch (obj->state) {
695 case ODEBUG_STATE_ACTIVE:
696 debug_print_object(obj, "free");
699 raw_spin_unlock_irqrestore(&db->lock, flags);
700 debug_object_fixup(descr->fixup_free,
701 (void *) oaddr, state);
704 hlist_del(&obj->node);
705 hlist_add_head(&obj->node, &freelist);
709 raw_spin_unlock_irqrestore(&db->lock, flags);
712 hlist_for_each_entry_safe(obj, tmp, &freelist, node) {
713 hlist_del(&obj->node);
717 if (cnt > debug_objects_maxchain)
718 debug_objects_maxchain = cnt;
722 void debug_check_no_obj_freed(const void *address, unsigned long size)
724 if (debug_objects_enabled)
725 __debug_check_no_obj_freed(address, size);
729 #ifdef CONFIG_DEBUG_FS
731 static int debug_stats_show(struct seq_file *m, void *v)
733 seq_printf(m, "max_chain :%d\n", debug_objects_maxchain);
734 seq_printf(m, "warnings :%d\n", debug_objects_warnings);
735 seq_printf(m, "fixups :%d\n", debug_objects_fixups);
736 seq_printf(m, "pool_free :%d\n", obj_pool_free);
737 seq_printf(m, "pool_min_free :%d\n", obj_pool_min_free);
738 seq_printf(m, "pool_used :%d\n", obj_pool_used);
739 seq_printf(m, "pool_max_used :%d\n", obj_pool_max_used);
743 static int debug_stats_open(struct inode *inode, struct file *filp)
745 return single_open(filp, debug_stats_show, NULL);
748 static const struct file_operations debug_stats_fops = {
749 .open = debug_stats_open,
752 .release = single_release,
755 static int __init debug_objects_init_debugfs(void)
757 struct dentry *dbgdir, *dbgstats;
759 if (!debug_objects_enabled)
762 dbgdir = debugfs_create_dir("debug_objects", NULL);
766 dbgstats = debugfs_create_file("stats", 0444, dbgdir, NULL,
774 debugfs_remove(dbgdir);
778 __initcall(debug_objects_init_debugfs);
781 static inline void debug_objects_init_debugfs(void) { }
784 #ifdef CONFIG_DEBUG_OBJECTS_SELFTEST
786 /* Random data structure for the self test */
788 unsigned long dummy1[6];
790 unsigned long dummy2[3];
793 static __initdata struct debug_obj_descr descr_type_test;
796 * fixup_init is called when:
797 * - an active object is initialized
799 static bool __init fixup_init(void *addr, enum debug_obj_state state)
801 struct self_test *obj = addr;
804 case ODEBUG_STATE_ACTIVE:
805 debug_object_deactivate(obj, &descr_type_test);
806 debug_object_init(obj, &descr_type_test);
814 * fixup_activate is called when:
815 * - an active object is activated
816 * - an unknown object is activated (might be a statically initialized object)
818 static bool __init fixup_activate(void *addr, enum debug_obj_state state)
820 struct self_test *obj = addr;
823 case ODEBUG_STATE_NOTAVAILABLE:
824 if (obj->static_init == 1) {
825 debug_object_init(obj, &descr_type_test);
826 debug_object_activate(obj, &descr_type_test);
831 case ODEBUG_STATE_ACTIVE:
832 debug_object_deactivate(obj, &descr_type_test);
833 debug_object_activate(obj, &descr_type_test);
842 * fixup_destroy is called when:
843 * - an active object is destroyed
845 static bool __init fixup_destroy(void *addr, enum debug_obj_state state)
847 struct self_test *obj = addr;
850 case ODEBUG_STATE_ACTIVE:
851 debug_object_deactivate(obj, &descr_type_test);
852 debug_object_destroy(obj, &descr_type_test);
860 * fixup_free is called when:
861 * - an active object is freed
863 static bool __init fixup_free(void *addr, enum debug_obj_state state)
865 struct self_test *obj = addr;
868 case ODEBUG_STATE_ACTIVE:
869 debug_object_deactivate(obj, &descr_type_test);
870 debug_object_free(obj, &descr_type_test);
878 check_results(void *addr, enum debug_obj_state state, int fixups, int warnings)
880 struct debug_bucket *db;
881 struct debug_obj *obj;
885 db = get_bucket((unsigned long) addr);
887 raw_spin_lock_irqsave(&db->lock, flags);
889 obj = lookup_object(addr, db);
890 if (!obj && state != ODEBUG_STATE_NONE) {
891 WARN(1, KERN_ERR "ODEBUG: selftest object not found\n");
894 if (obj && obj->state != state) {
895 WARN(1, KERN_ERR "ODEBUG: selftest wrong state: %d != %d\n",
899 if (fixups != debug_objects_fixups) {
900 WARN(1, KERN_ERR "ODEBUG: selftest fixups failed %d != %d\n",
901 fixups, debug_objects_fixups);
904 if (warnings != debug_objects_warnings) {
905 WARN(1, KERN_ERR "ODEBUG: selftest warnings failed %d != %d\n",
906 warnings, debug_objects_warnings);
911 raw_spin_unlock_irqrestore(&db->lock, flags);
913 debug_objects_enabled = 0;
917 static __initdata struct debug_obj_descr descr_type_test = {
919 .fixup_init = fixup_init,
920 .fixup_activate = fixup_activate,
921 .fixup_destroy = fixup_destroy,
922 .fixup_free = fixup_free,
925 static __initdata struct self_test obj = { .static_init = 0 };
927 static void __init debug_objects_selftest(void)
929 int fixups, oldfixups, warnings, oldwarnings;
932 local_irq_save(flags);
934 fixups = oldfixups = debug_objects_fixups;
935 warnings = oldwarnings = debug_objects_warnings;
936 descr_test = &descr_type_test;
938 debug_object_init(&obj, &descr_type_test);
939 if (check_results(&obj, ODEBUG_STATE_INIT, fixups, warnings))
941 debug_object_activate(&obj, &descr_type_test);
942 if (check_results(&obj, ODEBUG_STATE_ACTIVE, fixups, warnings))
944 debug_object_activate(&obj, &descr_type_test);
945 if (check_results(&obj, ODEBUG_STATE_ACTIVE, ++fixups, ++warnings))
947 debug_object_deactivate(&obj, &descr_type_test);
948 if (check_results(&obj, ODEBUG_STATE_INACTIVE, fixups, warnings))
950 debug_object_destroy(&obj, &descr_type_test);
951 if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, warnings))
953 debug_object_init(&obj, &descr_type_test);
954 if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, ++warnings))
956 debug_object_activate(&obj, &descr_type_test);
957 if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, ++warnings))
959 debug_object_deactivate(&obj, &descr_type_test);
960 if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, ++warnings))
962 debug_object_free(&obj, &descr_type_test);
963 if (check_results(&obj, ODEBUG_STATE_NONE, fixups, warnings))
967 debug_object_activate(&obj, &descr_type_test);
968 if (check_results(&obj, ODEBUG_STATE_ACTIVE, fixups, warnings))
970 debug_object_init(&obj, &descr_type_test);
971 if (check_results(&obj, ODEBUG_STATE_INIT, ++fixups, ++warnings))
973 debug_object_free(&obj, &descr_type_test);
974 if (check_results(&obj, ODEBUG_STATE_NONE, fixups, warnings))
977 #ifdef CONFIG_DEBUG_OBJECTS_FREE
978 debug_object_init(&obj, &descr_type_test);
979 if (check_results(&obj, ODEBUG_STATE_INIT, fixups, warnings))
981 debug_object_activate(&obj, &descr_type_test);
982 if (check_results(&obj, ODEBUG_STATE_ACTIVE, fixups, warnings))
984 __debug_check_no_obj_freed(&obj, sizeof(obj));
985 if (check_results(&obj, ODEBUG_STATE_NONE, ++fixups, ++warnings))
988 pr_info("selftest passed\n");
991 debug_objects_fixups = oldfixups;
992 debug_objects_warnings = oldwarnings;
995 local_irq_restore(flags);
998 static inline void debug_objects_selftest(void) { }
1002 * Called during early boot to initialize the hash buckets and link
1003 * the static object pool objects into the poll list. After this call
1004 * the object tracker is fully operational.
1006 void __init debug_objects_early_init(void)
1010 for (i = 0; i < ODEBUG_HASH_SIZE; i++)
1011 raw_spin_lock_init(&obj_hash[i].lock);
1013 for (i = 0; i < ODEBUG_POOL_SIZE; i++)
1014 hlist_add_head(&obj_static_pool[i].node, &obj_pool);
1018 * Convert the statically allocated objects to dynamic ones:
1020 static int __init debug_objects_replace_static_objects(void)
1022 struct debug_bucket *db = obj_hash;
1023 struct hlist_node *tmp;
1024 struct debug_obj *obj, *new;
1025 HLIST_HEAD(objects);
1028 for (i = 0; i < ODEBUG_POOL_SIZE; i++) {
1029 obj = kmem_cache_zalloc(obj_cache, GFP_KERNEL);
1032 hlist_add_head(&obj->node, &objects);
1036 * When debug_objects_mem_init() is called we know that only
1037 * one CPU is up, so disabling interrupts is enough
1038 * protection. This avoids the lockdep hell of lock ordering.
1040 local_irq_disable();
1042 /* Remove the statically allocated objects from the pool */
1043 hlist_for_each_entry_safe(obj, tmp, &obj_pool, node)
1044 hlist_del(&obj->node);
1045 /* Move the allocated objects to the pool */
1046 hlist_move_list(&objects, &obj_pool);
1048 /* Replace the active object references */
1049 for (i = 0; i < ODEBUG_HASH_SIZE; i++, db++) {
1050 hlist_move_list(&db->list, &objects);
1052 hlist_for_each_entry(obj, &objects, node) {
1053 new = hlist_entry(obj_pool.first, typeof(*obj), node);
1054 hlist_del(&new->node);
1055 /* copy object data */
1057 hlist_add_head(&new->node, &db->list);
1063 pr_debug("%d of %d active objects replaced\n",
1064 cnt, obj_pool_used);
1067 hlist_for_each_entry_safe(obj, tmp, &objects, node) {
1068 hlist_del(&obj->node);
1069 kmem_cache_free(obj_cache, obj);
1075 * Called after the kmem_caches are functional to setup a dedicated
1076 * cache pool, which has the SLAB_DEBUG_OBJECTS flag set. This flag
1077 * prevents that the debug code is called on kmem_cache_free() for the
1078 * debug tracker objects to avoid recursive calls.
1080 void __init debug_objects_mem_init(void)
1082 if (!debug_objects_enabled)
1085 obj_cache = kmem_cache_create("debug_objects_cache",
1086 sizeof (struct debug_obj), 0,
1087 SLAB_DEBUG_OBJECTS, NULL);
1089 if (!obj_cache || debug_objects_replace_static_objects()) {
1090 debug_objects_enabled = 0;
1092 kmem_cache_destroy(obj_cache);
1093 pr_warn("out of memory.\n");
1095 debug_objects_selftest();