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
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>
18 #define ODEBUG_HASH_BITS 14
19 #define ODEBUG_HASH_SIZE (1 << ODEBUG_HASH_BITS)
21 #define ODEBUG_POOL_SIZE 512
22 #define ODEBUG_POOL_MIN_LEVEL 256
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))
29 struct hlist_head list;
33 static struct debug_bucket obj_hash[ODEBUG_HASH_SIZE];
35 static struct debug_obj obj_static_pool[ODEBUG_POOL_SIZE] __initdata;
37 static DEFINE_RAW_SPINLOCK(pool_lock);
39 static HLIST_HEAD(obj_pool);
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;
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;
53 static struct debug_obj_descr *descr_test __read_mostly;
55 static void free_obj_work(struct work_struct *work);
56 static DECLARE_WORK(debug_obj_work, free_obj_work);
58 static int __init enable_object_debug(char *str)
60 debug_objects_enabled = 1;
64 static int __init disable_object_debug(char *str)
66 debug_objects_enabled = 0;
70 early_param("debug_objects", enable_object_debug);
71 early_param("no_debug_objects", disable_object_debug);
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",
82 static int fill_pool(void)
84 gfp_t gfp = GFP_ATOMIC | __GFP_NORETRY | __GFP_NOWARN;
85 struct debug_obj *new;
88 if (likely(obj_pool_free >= ODEBUG_POOL_MIN_LEVEL))
91 if (unlikely(!obj_cache))
94 while (obj_pool_free < ODEBUG_POOL_MIN_LEVEL) {
96 new = kmem_cache_zalloc(obj_cache, gfp);
100 raw_spin_lock_irqsave(&pool_lock, flags);
101 hlist_add_head(&new->node, &obj_pool);
103 raw_spin_unlock_irqrestore(&pool_lock, flags);
105 return obj_pool_free;
109 * Lookup an object in the hash bucket.
111 static struct debug_obj *lookup_object(void *addr, struct debug_bucket *b)
113 struct hlist_node *node;
114 struct debug_obj *obj;
117 hlist_for_each_entry(obj, node, &b->list, node) {
119 if (obj->object == addr)
122 if (cnt > debug_objects_maxchain)
123 debug_objects_maxchain = cnt;
129 * Allocate a new object. If the pool is empty, switch off the debugger.
130 * Must be called with interrupts disabled.
132 static struct debug_obj *
133 alloc_object(void *addr, struct debug_bucket *b, struct debug_obj_descr *descr)
135 struct debug_obj *obj = NULL;
137 raw_spin_lock(&pool_lock);
138 if (obj_pool.first) {
139 obj = hlist_entry(obj_pool.first, typeof(*obj), node);
143 obj->state = ODEBUG_STATE_NONE;
145 hlist_del(&obj->node);
147 hlist_add_head(&obj->node, &b->list);
150 if (obj_pool_used > obj_pool_max_used)
151 obj_pool_max_used = obj_pool_used;
154 if (obj_pool_free < obj_pool_min_free)
155 obj_pool_min_free = obj_pool_free;
157 raw_spin_unlock(&pool_lock);
163 * workqueue function to free objects.
165 static void free_obj_work(struct work_struct *work)
167 struct debug_obj *obj;
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);
176 * We release pool_lock across kmem_cache_free() to
177 * avoid contention on pool_lock.
179 raw_spin_unlock_irqrestore(&pool_lock, flags);
180 kmem_cache_free(obj_cache, obj);
181 raw_spin_lock_irqsave(&pool_lock, flags);
183 raw_spin_unlock_irqrestore(&pool_lock, flags);
187 * Put the object back into the pool and schedule work to free objects
190 static void free_object(struct debug_obj *obj)
195 raw_spin_lock_irqsave(&pool_lock, flags);
197 * schedule work when the pool is filled and the cache is
200 if (obj_pool_free > ODEBUG_POOL_SIZE && obj_cache)
201 sched = keventd_up() && !work_pending(&debug_obj_work);
202 hlist_add_head(&obj->node, &obj_pool);
205 raw_spin_unlock_irqrestore(&pool_lock, flags);
207 schedule_work(&debug_obj_work);
211 * We run out of memory. That means we probably have tons of objects
214 static void debug_objects_oom(void)
216 struct debug_bucket *db = obj_hash;
217 struct hlist_node *node, *tmp;
218 HLIST_HEAD(freelist);
219 struct debug_obj *obj;
223 printk(KERN_WARNING "ODEBUG: Out of memory. ODEBUG disabled\n");
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);
231 hlist_for_each_entry_safe(obj, node, tmp, &freelist, node) {
232 hlist_del(&obj->node);
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.
242 static struct debug_bucket *get_bucket(unsigned long addr)
246 hash = hash_long((addr >> ODEBUG_CHUNK_SHIFT), ODEBUG_HASH_BITS);
247 return &obj_hash[hash];
250 static void debug_print_object(struct debug_obj *obj, char *msg)
252 struct debug_obj_descr *descr = obj->descr;
255 if (limit < 5 && descr != descr_test) {
256 void *hint = descr->debug_hint ?
257 descr->debug_hint(obj->object) : NULL;
259 WARN(1, KERN_ERR "ODEBUG: %s %s (active state %u) "
260 "object type: %s hint: %pS\n",
261 msg, obj_states[obj->state], obj->astate,
264 debug_objects_warnings++;
268 * Try to repair the damage, so we have a better chance to get useful
272 debug_object_fixup(int (*fixup)(void *addr, enum debug_obj_state state),
273 void * addr, enum debug_obj_state state)
276 debug_objects_fixups += fixup(addr, state);
279 static void debug_object_is_on_stack(void *addr, int onstack)
287 is_on_stack = object_is_on_stack(addr);
288 if (is_on_stack == onstack)
294 "ODEBUG: object is on stack, but not annotated\n");
297 "ODEBUG: object is not on stack, but annotated\n");
302 __debug_object_init(void *addr, struct debug_obj_descr *descr, int onstack)
304 enum debug_obj_state state;
305 struct debug_bucket *db;
306 struct debug_obj *obj;
311 db = get_bucket((unsigned long) addr);
313 raw_spin_lock_irqsave(&db->lock, flags);
315 obj = lookup_object(addr, db);
317 obj = alloc_object(addr, db, descr);
319 debug_objects_enabled = 0;
320 raw_spin_unlock_irqrestore(&db->lock, flags);
324 debug_object_is_on_stack(addr, onstack);
327 switch (obj->state) {
328 case ODEBUG_STATE_NONE:
329 case ODEBUG_STATE_INIT:
330 case ODEBUG_STATE_INACTIVE:
331 obj->state = ODEBUG_STATE_INIT;
334 case ODEBUG_STATE_ACTIVE:
335 debug_print_object(obj, "init");
337 raw_spin_unlock_irqrestore(&db->lock, flags);
338 debug_object_fixup(descr->fixup_init, addr, state);
341 case ODEBUG_STATE_DESTROYED:
342 debug_print_object(obj, "init");
348 raw_spin_unlock_irqrestore(&db->lock, flags);
352 * debug_object_init - debug checks when an object is initialized
353 * @addr: address of the object
354 * @descr: pointer to an object specific debug description structure
356 void debug_object_init(void *addr, struct debug_obj_descr *descr)
358 if (!debug_objects_enabled)
361 __debug_object_init(addr, descr, 0);
365 * debug_object_init_on_stack - debug checks when an object on stack is
367 * @addr: address of the object
368 * @descr: pointer to an object specific debug description structure
370 void debug_object_init_on_stack(void *addr, struct debug_obj_descr *descr)
372 if (!debug_objects_enabled)
375 __debug_object_init(addr, descr, 1);
379 * debug_object_activate - debug checks when an object is activated
380 * @addr: address of the object
381 * @descr: pointer to an object specific debug description structure
383 void debug_object_activate(void *addr, struct debug_obj_descr *descr)
385 enum debug_obj_state state;
386 struct debug_bucket *db;
387 struct debug_obj *obj;
390 if (!debug_objects_enabled)
393 db = get_bucket((unsigned long) addr);
395 raw_spin_lock_irqsave(&db->lock, flags);
397 obj = lookup_object(addr, db);
399 switch (obj->state) {
400 case ODEBUG_STATE_INIT:
401 case ODEBUG_STATE_INACTIVE:
402 obj->state = ODEBUG_STATE_ACTIVE;
405 case ODEBUG_STATE_ACTIVE:
406 debug_print_object(obj, "activate");
408 raw_spin_unlock_irqrestore(&db->lock, flags);
409 debug_object_fixup(descr->fixup_activate, addr, state);
412 case ODEBUG_STATE_DESTROYED:
413 debug_print_object(obj, "activate");
418 raw_spin_unlock_irqrestore(&db->lock, flags);
422 raw_spin_unlock_irqrestore(&db->lock, flags);
424 * This happens when a static object is activated. We
425 * let the type specific code decide whether this is
428 debug_object_fixup(descr->fixup_activate, addr,
429 ODEBUG_STATE_NOTAVAILABLE);
433 * debug_object_deactivate - debug checks when an object is deactivated
434 * @addr: address of the object
435 * @descr: pointer to an object specific debug description structure
437 void debug_object_deactivate(void *addr, struct debug_obj_descr *descr)
439 struct debug_bucket *db;
440 struct debug_obj *obj;
443 if (!debug_objects_enabled)
446 db = get_bucket((unsigned long) addr);
448 raw_spin_lock_irqsave(&db->lock, flags);
450 obj = lookup_object(addr, db);
452 switch (obj->state) {
453 case ODEBUG_STATE_INIT:
454 case ODEBUG_STATE_INACTIVE:
455 case ODEBUG_STATE_ACTIVE:
457 obj->state = ODEBUG_STATE_INACTIVE;
459 debug_print_object(obj, "deactivate");
462 case ODEBUG_STATE_DESTROYED:
463 debug_print_object(obj, "deactivate");
469 struct debug_obj o = { .object = addr,
470 .state = ODEBUG_STATE_NOTAVAILABLE,
473 debug_print_object(&o, "deactivate");
476 raw_spin_unlock_irqrestore(&db->lock, flags);
480 * debug_object_destroy - debug checks when an object is destroyed
481 * @addr: address of the object
482 * @descr: pointer to an object specific debug description structure
484 void debug_object_destroy(void *addr, struct debug_obj_descr *descr)
486 enum debug_obj_state state;
487 struct debug_bucket *db;
488 struct debug_obj *obj;
491 if (!debug_objects_enabled)
494 db = get_bucket((unsigned long) addr);
496 raw_spin_lock_irqsave(&db->lock, flags);
498 obj = lookup_object(addr, db);
502 switch (obj->state) {
503 case ODEBUG_STATE_NONE:
504 case ODEBUG_STATE_INIT:
505 case ODEBUG_STATE_INACTIVE:
506 obj->state = ODEBUG_STATE_DESTROYED;
508 case ODEBUG_STATE_ACTIVE:
509 debug_print_object(obj, "destroy");
511 raw_spin_unlock_irqrestore(&db->lock, flags);
512 debug_object_fixup(descr->fixup_destroy, addr, state);
515 case ODEBUG_STATE_DESTROYED:
516 debug_print_object(obj, "destroy");
522 raw_spin_unlock_irqrestore(&db->lock, flags);
526 * debug_object_free - debug checks when an object is freed
527 * @addr: address of the object
528 * @descr: pointer to an object specific debug description structure
530 void debug_object_free(void *addr, struct debug_obj_descr *descr)
532 enum debug_obj_state state;
533 struct debug_bucket *db;
534 struct debug_obj *obj;
537 if (!debug_objects_enabled)
540 db = get_bucket((unsigned long) addr);
542 raw_spin_lock_irqsave(&db->lock, flags);
544 obj = lookup_object(addr, db);
548 switch (obj->state) {
549 case ODEBUG_STATE_ACTIVE:
550 debug_print_object(obj, "free");
552 raw_spin_unlock_irqrestore(&db->lock, flags);
553 debug_object_fixup(descr->fixup_free, addr, state);
556 hlist_del(&obj->node);
557 raw_spin_unlock_irqrestore(&db->lock, flags);
562 raw_spin_unlock_irqrestore(&db->lock, flags);
566 * debug_object_assert_init - debug checks when object should be init-ed
567 * @addr: address of the object
568 * @descr: pointer to an object specific debug description structure
570 void debug_object_assert_init(void *addr, struct debug_obj_descr *descr)
572 struct debug_bucket *db;
573 struct debug_obj *obj;
576 if (!debug_objects_enabled)
579 db = get_bucket((unsigned long) addr);
581 raw_spin_lock_irqsave(&db->lock, flags);
583 obj = lookup_object(addr, db);
585 raw_spin_unlock_irqrestore(&db->lock, flags);
587 * Maybe the object is static. Let the type specific
588 * code decide what to do.
590 debug_object_fixup(descr->fixup_assert_init, addr,
591 ODEBUG_STATE_NOTAVAILABLE);
595 raw_spin_unlock_irqrestore(&db->lock, flags);
599 * debug_object_active_state - debug checks object usage state machine
600 * @addr: address of the object
601 * @descr: pointer to an object specific debug description structure
602 * @expect: expected state
603 * @next: state to move to if expected state is found
606 debug_object_active_state(void *addr, struct debug_obj_descr *descr,
607 unsigned int expect, unsigned int next)
609 struct debug_bucket *db;
610 struct debug_obj *obj;
613 if (!debug_objects_enabled)
616 db = get_bucket((unsigned long) addr);
618 raw_spin_lock_irqsave(&db->lock, flags);
620 obj = lookup_object(addr, db);
622 switch (obj->state) {
623 case ODEBUG_STATE_ACTIVE:
624 if (obj->astate == expect)
627 debug_print_object(obj, "active_state");
631 debug_print_object(obj, "active_state");
635 struct debug_obj o = { .object = addr,
636 .state = ODEBUG_STATE_NOTAVAILABLE,
639 debug_print_object(&o, "active_state");
642 raw_spin_unlock_irqrestore(&db->lock, flags);
645 #ifdef CONFIG_DEBUG_OBJECTS_FREE
646 static void __debug_check_no_obj_freed(const void *address, unsigned long size)
648 unsigned long flags, oaddr, saddr, eaddr, paddr, chunks;
649 struct hlist_node *node, *tmp;
650 HLIST_HEAD(freelist);
651 struct debug_obj_descr *descr;
652 enum debug_obj_state state;
653 struct debug_bucket *db;
654 struct debug_obj *obj;
657 saddr = (unsigned long) address;
658 eaddr = saddr + size;
659 paddr = saddr & ODEBUG_CHUNK_MASK;
660 chunks = ((eaddr - paddr) + (ODEBUG_CHUNK_SIZE - 1));
661 chunks >>= ODEBUG_CHUNK_SHIFT;
663 for (;chunks > 0; chunks--, paddr += ODEBUG_CHUNK_SIZE) {
664 db = get_bucket(paddr);
668 raw_spin_lock_irqsave(&db->lock, flags);
669 hlist_for_each_entry_safe(obj, node, tmp, &db->list, node) {
671 oaddr = (unsigned long) obj->object;
672 if (oaddr < saddr || oaddr >= eaddr)
675 switch (obj->state) {
676 case ODEBUG_STATE_ACTIVE:
677 debug_print_object(obj, "free");
680 raw_spin_unlock_irqrestore(&db->lock, flags);
681 debug_object_fixup(descr->fixup_free,
682 (void *) oaddr, state);
685 hlist_del(&obj->node);
686 hlist_add_head(&obj->node, &freelist);
690 raw_spin_unlock_irqrestore(&db->lock, flags);
693 hlist_for_each_entry_safe(obj, node, tmp, &freelist, node) {
694 hlist_del(&obj->node);
698 if (cnt > debug_objects_maxchain)
699 debug_objects_maxchain = cnt;
703 void debug_check_no_obj_freed(const void *address, unsigned long size)
705 if (debug_objects_enabled)
706 __debug_check_no_obj_freed(address, size);
710 #ifdef CONFIG_DEBUG_FS
712 static int debug_stats_show(struct seq_file *m, void *v)
714 seq_printf(m, "max_chain :%d\n", debug_objects_maxchain);
715 seq_printf(m, "warnings :%d\n", debug_objects_warnings);
716 seq_printf(m, "fixups :%d\n", debug_objects_fixups);
717 seq_printf(m, "pool_free :%d\n", obj_pool_free);
718 seq_printf(m, "pool_min_free :%d\n", obj_pool_min_free);
719 seq_printf(m, "pool_used :%d\n", obj_pool_used);
720 seq_printf(m, "pool_max_used :%d\n", obj_pool_max_used);
724 static int debug_stats_open(struct inode *inode, struct file *filp)
726 return single_open(filp, debug_stats_show, NULL);
729 static const struct file_operations debug_stats_fops = {
730 .open = debug_stats_open,
733 .release = single_release,
736 static int __init debug_objects_init_debugfs(void)
738 struct dentry *dbgdir, *dbgstats;
740 if (!debug_objects_enabled)
743 dbgdir = debugfs_create_dir("debug_objects", NULL);
747 dbgstats = debugfs_create_file("stats", 0444, dbgdir, NULL,
755 debugfs_remove(dbgdir);
759 __initcall(debug_objects_init_debugfs);
762 static inline void debug_objects_init_debugfs(void) { }
765 #ifdef CONFIG_DEBUG_OBJECTS_SELFTEST
767 /* Random data structure for the self test */
769 unsigned long dummy1[6];
771 unsigned long dummy2[3];
774 static __initdata struct debug_obj_descr descr_type_test;
777 * fixup_init is called when:
778 * - an active object is initialized
780 static int __init fixup_init(void *addr, enum debug_obj_state state)
782 struct self_test *obj = addr;
785 case ODEBUG_STATE_ACTIVE:
786 debug_object_deactivate(obj, &descr_type_test);
787 debug_object_init(obj, &descr_type_test);
795 * fixup_activate is called when:
796 * - an active object is activated
797 * - an unknown object is activated (might be a statically initialized object)
799 static int __init fixup_activate(void *addr, enum debug_obj_state state)
801 struct self_test *obj = addr;
804 case ODEBUG_STATE_NOTAVAILABLE:
805 if (obj->static_init == 1) {
806 debug_object_init(obj, &descr_type_test);
807 debug_object_activate(obj, &descr_type_test);
809 * Real code should return 0 here ! This is
810 * not a fixup of some bad behaviour. We
811 * merily call the debug_init function to keep
812 * track of the object.
816 /* Real code needs to emit a warning here */
820 case ODEBUG_STATE_ACTIVE:
821 debug_object_deactivate(obj, &descr_type_test);
822 debug_object_activate(obj, &descr_type_test);
831 * fixup_destroy is called when:
832 * - an active object is destroyed
834 static int __init fixup_destroy(void *addr, enum debug_obj_state state)
836 struct self_test *obj = addr;
839 case ODEBUG_STATE_ACTIVE:
840 debug_object_deactivate(obj, &descr_type_test);
841 debug_object_destroy(obj, &descr_type_test);
849 * fixup_free is called when:
850 * - an active object is freed
852 static int __init fixup_free(void *addr, enum debug_obj_state state)
854 struct self_test *obj = addr;
857 case ODEBUG_STATE_ACTIVE:
858 debug_object_deactivate(obj, &descr_type_test);
859 debug_object_free(obj, &descr_type_test);
867 check_results(void *addr, enum debug_obj_state state, int fixups, int warnings)
869 struct debug_bucket *db;
870 struct debug_obj *obj;
874 db = get_bucket((unsigned long) addr);
876 raw_spin_lock_irqsave(&db->lock, flags);
878 obj = lookup_object(addr, db);
879 if (!obj && state != ODEBUG_STATE_NONE) {
880 WARN(1, KERN_ERR "ODEBUG: selftest object not found\n");
883 if (obj && obj->state != state) {
884 WARN(1, KERN_ERR "ODEBUG: selftest wrong state: %d != %d\n",
888 if (fixups != debug_objects_fixups) {
889 WARN(1, KERN_ERR "ODEBUG: selftest fixups failed %d != %d\n",
890 fixups, debug_objects_fixups);
893 if (warnings != debug_objects_warnings) {
894 WARN(1, KERN_ERR "ODEBUG: selftest warnings failed %d != %d\n",
895 warnings, debug_objects_warnings);
900 raw_spin_unlock_irqrestore(&db->lock, flags);
902 debug_objects_enabled = 0;
906 static __initdata struct debug_obj_descr descr_type_test = {
908 .fixup_init = fixup_init,
909 .fixup_activate = fixup_activate,
910 .fixup_destroy = fixup_destroy,
911 .fixup_free = fixup_free,
914 static __initdata struct self_test obj = { .static_init = 0 };
916 static void __init debug_objects_selftest(void)
918 int fixups, oldfixups, warnings, oldwarnings;
921 local_irq_save(flags);
923 fixups = oldfixups = debug_objects_fixups;
924 warnings = oldwarnings = debug_objects_warnings;
925 descr_test = &descr_type_test;
927 debug_object_init(&obj, &descr_type_test);
928 if (check_results(&obj, ODEBUG_STATE_INIT, fixups, warnings))
930 debug_object_activate(&obj, &descr_type_test);
931 if (check_results(&obj, ODEBUG_STATE_ACTIVE, fixups, warnings))
933 debug_object_activate(&obj, &descr_type_test);
934 if (check_results(&obj, ODEBUG_STATE_ACTIVE, ++fixups, ++warnings))
936 debug_object_deactivate(&obj, &descr_type_test);
937 if (check_results(&obj, ODEBUG_STATE_INACTIVE, fixups, warnings))
939 debug_object_destroy(&obj, &descr_type_test);
940 if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, warnings))
942 debug_object_init(&obj, &descr_type_test);
943 if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, ++warnings))
945 debug_object_activate(&obj, &descr_type_test);
946 if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, ++warnings))
948 debug_object_deactivate(&obj, &descr_type_test);
949 if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, ++warnings))
951 debug_object_free(&obj, &descr_type_test);
952 if (check_results(&obj, ODEBUG_STATE_NONE, fixups, warnings))
956 debug_object_activate(&obj, &descr_type_test);
957 if (check_results(&obj, ODEBUG_STATE_ACTIVE, ++fixups, warnings))
959 debug_object_init(&obj, &descr_type_test);
960 if (check_results(&obj, ODEBUG_STATE_INIT, ++fixups, ++warnings))
962 debug_object_free(&obj, &descr_type_test);
963 if (check_results(&obj, ODEBUG_STATE_NONE, fixups, warnings))
966 #ifdef CONFIG_DEBUG_OBJECTS_FREE
967 debug_object_init(&obj, &descr_type_test);
968 if (check_results(&obj, ODEBUG_STATE_INIT, fixups, warnings))
970 debug_object_activate(&obj, &descr_type_test);
971 if (check_results(&obj, ODEBUG_STATE_ACTIVE, fixups, warnings))
973 __debug_check_no_obj_freed(&obj, sizeof(obj));
974 if (check_results(&obj, ODEBUG_STATE_NONE, ++fixups, ++warnings))
977 printk(KERN_INFO "ODEBUG: selftest passed\n");
980 debug_objects_fixups = oldfixups;
981 debug_objects_warnings = oldwarnings;
984 local_irq_restore(flags);
987 static inline void debug_objects_selftest(void) { }
991 * Called during early boot to initialize the hash buckets and link
992 * the static object pool objects into the poll list. After this call
993 * the object tracker is fully operational.
995 void __init debug_objects_early_init(void)
999 for (i = 0; i < ODEBUG_HASH_SIZE; i++)
1000 raw_spin_lock_init(&obj_hash[i].lock);
1002 for (i = 0; i < ODEBUG_POOL_SIZE; i++)
1003 hlist_add_head(&obj_static_pool[i].node, &obj_pool);
1007 * Convert the statically allocated objects to dynamic ones:
1009 static int __init debug_objects_replace_static_objects(void)
1011 struct debug_bucket *db = obj_hash;
1012 struct hlist_node *node, *tmp;
1013 struct debug_obj *obj, *new;
1014 HLIST_HEAD(objects);
1017 for (i = 0; i < ODEBUG_POOL_SIZE; i++) {
1018 obj = kmem_cache_zalloc(obj_cache, GFP_KERNEL);
1021 hlist_add_head(&obj->node, &objects);
1025 * When debug_objects_mem_init() is called we know that only
1026 * one CPU is up, so disabling interrupts is enough
1027 * protection. This avoids the lockdep hell of lock ordering.
1029 local_irq_disable();
1031 /* Remove the statically allocated objects from the pool */
1032 hlist_for_each_entry_safe(obj, node, tmp, &obj_pool, node)
1033 hlist_del(&obj->node);
1034 /* Move the allocated objects to the pool */
1035 hlist_move_list(&objects, &obj_pool);
1037 /* Replace the active object references */
1038 for (i = 0; i < ODEBUG_HASH_SIZE; i++, db++) {
1039 hlist_move_list(&db->list, &objects);
1041 hlist_for_each_entry(obj, node, &objects, node) {
1042 new = hlist_entry(obj_pool.first, typeof(*obj), node);
1043 hlist_del(&new->node);
1044 /* copy object data */
1046 hlist_add_head(&new->node, &db->list);
1051 printk(KERN_DEBUG "ODEBUG: %d of %d active objects replaced\n", cnt,
1056 hlist_for_each_entry_safe(obj, node, tmp, &objects, node) {
1057 hlist_del(&obj->node);
1058 kmem_cache_free(obj_cache, obj);
1064 * Called after the kmem_caches are functional to setup a dedicated
1065 * cache pool, which has the SLAB_DEBUG_OBJECTS flag set. This flag
1066 * prevents that the debug code is called on kmem_cache_free() for the
1067 * debug tracker objects to avoid recursive calls.
1069 void __init debug_objects_mem_init(void)
1071 if (!debug_objects_enabled)
1074 obj_cache = kmem_cache_create("debug_objects_cache",
1075 sizeof (struct debug_obj), 0,
1076 SLAB_DEBUG_OBJECTS, NULL);
1078 if (!obj_cache || debug_objects_replace_static_objects()) {
1079 debug_objects_enabled = 0;
1081 kmem_cache_destroy(obj_cache);
1082 printk(KERN_WARNING "ODEBUG: out of memory.\n");
1084 debug_objects_selftest();