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 %p is on stack %p, but NOT annotated.\n", addr,
298 task_stack_page(current));
300 pr_warn("object %p is NOT on stack %p, but annotated.\n", addr,
301 task_stack_page(current));
307 __debug_object_init(void *addr, struct debug_obj_descr *descr, int onstack)
309 enum debug_obj_state state;
310 struct debug_bucket *db;
311 struct debug_obj *obj;
316 db = get_bucket((unsigned long) addr);
318 raw_spin_lock_irqsave(&db->lock, flags);
320 obj = lookup_object(addr, db);
322 obj = alloc_object(addr, db, descr);
324 debug_objects_enabled = 0;
325 raw_spin_unlock_irqrestore(&db->lock, flags);
329 debug_object_is_on_stack(addr, onstack);
332 switch (obj->state) {
333 case ODEBUG_STATE_NONE:
334 case ODEBUG_STATE_INIT:
335 case ODEBUG_STATE_INACTIVE:
336 obj->state = ODEBUG_STATE_INIT;
339 case ODEBUG_STATE_ACTIVE:
340 debug_print_object(obj, "init");
342 raw_spin_unlock_irqrestore(&db->lock, flags);
343 debug_object_fixup(descr->fixup_init, addr, state);
346 case ODEBUG_STATE_DESTROYED:
347 debug_print_object(obj, "init");
353 raw_spin_unlock_irqrestore(&db->lock, flags);
357 * debug_object_init - debug checks when an object is initialized
358 * @addr: address of the object
359 * @descr: pointer to an object specific debug description structure
361 void debug_object_init(void *addr, struct debug_obj_descr *descr)
363 if (!debug_objects_enabled)
366 __debug_object_init(addr, descr, 0);
368 EXPORT_SYMBOL_GPL(debug_object_init);
371 * debug_object_init_on_stack - debug checks when an object on stack is
373 * @addr: address of the object
374 * @descr: pointer to an object specific debug description structure
376 void debug_object_init_on_stack(void *addr, struct debug_obj_descr *descr)
378 if (!debug_objects_enabled)
381 __debug_object_init(addr, descr, 1);
383 EXPORT_SYMBOL_GPL(debug_object_init_on_stack);
386 * debug_object_activate - debug checks when an object is activated
387 * @addr: address of the object
388 * @descr: pointer to an object specific debug description structure
389 * Returns 0 for success, -EINVAL for check failed.
391 int debug_object_activate(void *addr, struct debug_obj_descr *descr)
393 enum debug_obj_state state;
394 struct debug_bucket *db;
395 struct debug_obj *obj;
398 struct debug_obj o = { .object = addr,
399 .state = ODEBUG_STATE_NOTAVAILABLE,
402 if (!debug_objects_enabled)
405 db = get_bucket((unsigned long) addr);
407 raw_spin_lock_irqsave(&db->lock, flags);
409 obj = lookup_object(addr, db);
411 switch (obj->state) {
412 case ODEBUG_STATE_INIT:
413 case ODEBUG_STATE_INACTIVE:
414 obj->state = ODEBUG_STATE_ACTIVE;
418 case ODEBUG_STATE_ACTIVE:
419 debug_print_object(obj, "activate");
421 raw_spin_unlock_irqrestore(&db->lock, flags);
422 ret = debug_object_fixup(descr->fixup_activate, addr, state);
423 return ret ? 0 : -EINVAL;
425 case ODEBUG_STATE_DESTROYED:
426 debug_print_object(obj, "activate");
433 raw_spin_unlock_irqrestore(&db->lock, flags);
437 raw_spin_unlock_irqrestore(&db->lock, flags);
439 * We are here when a static object is activated. We
440 * let the type specific code confirm whether this is
441 * true or not. if true, we just make sure that the
442 * static object is tracked in the object tracker. If
443 * not, this must be a bug, so we try to fix it up.
445 if (descr->is_static_object && descr->is_static_object(addr)) {
446 /* track this static object */
447 debug_object_init(addr, descr);
448 debug_object_activate(addr, descr);
450 debug_print_object(&o, "activate");
451 ret = debug_object_fixup(descr->fixup_activate, addr,
452 ODEBUG_STATE_NOTAVAILABLE);
453 return ret ? 0 : -EINVAL;
457 EXPORT_SYMBOL_GPL(debug_object_activate);
460 * debug_object_deactivate - debug checks when an object is deactivated
461 * @addr: address of the object
462 * @descr: pointer to an object specific debug description structure
464 void debug_object_deactivate(void *addr, struct debug_obj_descr *descr)
466 struct debug_bucket *db;
467 struct debug_obj *obj;
470 if (!debug_objects_enabled)
473 db = get_bucket((unsigned long) addr);
475 raw_spin_lock_irqsave(&db->lock, flags);
477 obj = lookup_object(addr, db);
479 switch (obj->state) {
480 case ODEBUG_STATE_INIT:
481 case ODEBUG_STATE_INACTIVE:
482 case ODEBUG_STATE_ACTIVE:
484 obj->state = ODEBUG_STATE_INACTIVE;
486 debug_print_object(obj, "deactivate");
489 case ODEBUG_STATE_DESTROYED:
490 debug_print_object(obj, "deactivate");
496 struct debug_obj o = { .object = addr,
497 .state = ODEBUG_STATE_NOTAVAILABLE,
500 debug_print_object(&o, "deactivate");
503 raw_spin_unlock_irqrestore(&db->lock, flags);
505 EXPORT_SYMBOL_GPL(debug_object_deactivate);
508 * debug_object_destroy - debug checks when an object is destroyed
509 * @addr: address of the object
510 * @descr: pointer to an object specific debug description structure
512 void debug_object_destroy(void *addr, struct debug_obj_descr *descr)
514 enum debug_obj_state state;
515 struct debug_bucket *db;
516 struct debug_obj *obj;
519 if (!debug_objects_enabled)
522 db = get_bucket((unsigned long) addr);
524 raw_spin_lock_irqsave(&db->lock, flags);
526 obj = lookup_object(addr, db);
530 switch (obj->state) {
531 case ODEBUG_STATE_NONE:
532 case ODEBUG_STATE_INIT:
533 case ODEBUG_STATE_INACTIVE:
534 obj->state = ODEBUG_STATE_DESTROYED;
536 case ODEBUG_STATE_ACTIVE:
537 debug_print_object(obj, "destroy");
539 raw_spin_unlock_irqrestore(&db->lock, flags);
540 debug_object_fixup(descr->fixup_destroy, addr, state);
543 case ODEBUG_STATE_DESTROYED:
544 debug_print_object(obj, "destroy");
550 raw_spin_unlock_irqrestore(&db->lock, flags);
552 EXPORT_SYMBOL_GPL(debug_object_destroy);
555 * debug_object_free - debug checks when an object is freed
556 * @addr: address of the object
557 * @descr: pointer to an object specific debug description structure
559 void debug_object_free(void *addr, struct debug_obj_descr *descr)
561 enum debug_obj_state state;
562 struct debug_bucket *db;
563 struct debug_obj *obj;
566 if (!debug_objects_enabled)
569 db = get_bucket((unsigned long) addr);
571 raw_spin_lock_irqsave(&db->lock, flags);
573 obj = lookup_object(addr, db);
577 switch (obj->state) {
578 case ODEBUG_STATE_ACTIVE:
579 debug_print_object(obj, "free");
581 raw_spin_unlock_irqrestore(&db->lock, flags);
582 debug_object_fixup(descr->fixup_free, addr, state);
585 hlist_del(&obj->node);
586 raw_spin_unlock_irqrestore(&db->lock, flags);
591 raw_spin_unlock_irqrestore(&db->lock, flags);
593 EXPORT_SYMBOL_GPL(debug_object_free);
596 * debug_object_assert_init - debug checks when object should be init-ed
597 * @addr: address of the object
598 * @descr: pointer to an object specific debug description structure
600 void debug_object_assert_init(void *addr, struct debug_obj_descr *descr)
602 struct debug_bucket *db;
603 struct debug_obj *obj;
606 if (!debug_objects_enabled)
609 db = get_bucket((unsigned long) addr);
611 raw_spin_lock_irqsave(&db->lock, flags);
613 obj = lookup_object(addr, db);
615 struct debug_obj o = { .object = addr,
616 .state = ODEBUG_STATE_NOTAVAILABLE,
619 raw_spin_unlock_irqrestore(&db->lock, flags);
621 * Maybe the object is static, and we let the type specific
622 * code confirm. Track this static object if true, else invoke
625 if (descr->is_static_object && descr->is_static_object(addr)) {
626 /* Track this static object */
627 debug_object_init(addr, descr);
629 debug_print_object(&o, "assert_init");
630 debug_object_fixup(descr->fixup_assert_init, addr,
631 ODEBUG_STATE_NOTAVAILABLE);
636 raw_spin_unlock_irqrestore(&db->lock, flags);
638 EXPORT_SYMBOL_GPL(debug_object_assert_init);
641 * debug_object_active_state - debug checks object usage state machine
642 * @addr: address of the object
643 * @descr: pointer to an object specific debug description structure
644 * @expect: expected state
645 * @next: state to move to if expected state is found
648 debug_object_active_state(void *addr, struct debug_obj_descr *descr,
649 unsigned int expect, unsigned int next)
651 struct debug_bucket *db;
652 struct debug_obj *obj;
655 if (!debug_objects_enabled)
658 db = get_bucket((unsigned long) addr);
660 raw_spin_lock_irqsave(&db->lock, flags);
662 obj = lookup_object(addr, db);
664 switch (obj->state) {
665 case ODEBUG_STATE_ACTIVE:
666 if (obj->astate == expect)
669 debug_print_object(obj, "active_state");
673 debug_print_object(obj, "active_state");
677 struct debug_obj o = { .object = addr,
678 .state = ODEBUG_STATE_NOTAVAILABLE,
681 debug_print_object(&o, "active_state");
684 raw_spin_unlock_irqrestore(&db->lock, flags);
686 EXPORT_SYMBOL_GPL(debug_object_active_state);
688 #ifdef CONFIG_DEBUG_OBJECTS_FREE
689 static void __debug_check_no_obj_freed(const void *address, unsigned long size)
691 unsigned long flags, oaddr, saddr, eaddr, paddr, chunks;
692 struct hlist_node *tmp;
693 HLIST_HEAD(freelist);
694 struct debug_obj_descr *descr;
695 enum debug_obj_state state;
696 struct debug_bucket *db;
697 struct debug_obj *obj;
700 saddr = (unsigned long) address;
701 eaddr = saddr + size;
702 paddr = saddr & ODEBUG_CHUNK_MASK;
703 chunks = ((eaddr - paddr) + (ODEBUG_CHUNK_SIZE - 1));
704 chunks >>= ODEBUG_CHUNK_SHIFT;
706 for (;chunks > 0; chunks--, paddr += ODEBUG_CHUNK_SIZE) {
707 db = get_bucket(paddr);
711 raw_spin_lock_irqsave(&db->lock, flags);
712 hlist_for_each_entry_safe(obj, tmp, &db->list, node) {
714 oaddr = (unsigned long) obj->object;
715 if (oaddr < saddr || oaddr >= eaddr)
718 switch (obj->state) {
719 case ODEBUG_STATE_ACTIVE:
720 debug_print_object(obj, "free");
723 raw_spin_unlock_irqrestore(&db->lock, flags);
724 debug_object_fixup(descr->fixup_free,
725 (void *) oaddr, state);
728 hlist_del(&obj->node);
729 hlist_add_head(&obj->node, &freelist);
733 raw_spin_unlock_irqrestore(&db->lock, flags);
736 hlist_for_each_entry_safe(obj, tmp, &freelist, node) {
737 hlist_del(&obj->node);
741 if (cnt > debug_objects_maxchain)
742 debug_objects_maxchain = cnt;
746 void debug_check_no_obj_freed(const void *address, unsigned long size)
748 if (debug_objects_enabled)
749 __debug_check_no_obj_freed(address, size);
753 #ifdef CONFIG_DEBUG_FS
755 static int debug_stats_show(struct seq_file *m, void *v)
757 seq_printf(m, "max_chain :%d\n", debug_objects_maxchain);
758 seq_printf(m, "warnings :%d\n", debug_objects_warnings);
759 seq_printf(m, "fixups :%d\n", debug_objects_fixups);
760 seq_printf(m, "pool_free :%d\n", obj_pool_free);
761 seq_printf(m, "pool_min_free :%d\n", obj_pool_min_free);
762 seq_printf(m, "pool_used :%d\n", obj_pool_used);
763 seq_printf(m, "pool_max_used :%d\n", obj_pool_max_used);
767 static int debug_stats_open(struct inode *inode, struct file *filp)
769 return single_open(filp, debug_stats_show, NULL);
772 static const struct file_operations debug_stats_fops = {
773 .open = debug_stats_open,
776 .release = single_release,
779 static int __init debug_objects_init_debugfs(void)
781 struct dentry *dbgdir, *dbgstats;
783 if (!debug_objects_enabled)
786 dbgdir = debugfs_create_dir("debug_objects", NULL);
790 dbgstats = debugfs_create_file("stats", 0444, dbgdir, NULL,
798 debugfs_remove(dbgdir);
802 __initcall(debug_objects_init_debugfs);
805 static inline void debug_objects_init_debugfs(void) { }
808 #ifdef CONFIG_DEBUG_OBJECTS_SELFTEST
810 /* Random data structure for the self test */
812 unsigned long dummy1[6];
814 unsigned long dummy2[3];
817 static __initdata struct debug_obj_descr descr_type_test;
819 static bool __init is_static_object(void *addr)
821 struct self_test *obj = addr;
823 return obj->static_init;
827 * fixup_init is called when:
828 * - an active object is initialized
830 static bool __init fixup_init(void *addr, enum debug_obj_state state)
832 struct self_test *obj = addr;
835 case ODEBUG_STATE_ACTIVE:
836 debug_object_deactivate(obj, &descr_type_test);
837 debug_object_init(obj, &descr_type_test);
845 * fixup_activate is called when:
846 * - an active object is activated
847 * - an unknown non-static object is activated
849 static bool __init fixup_activate(void *addr, enum debug_obj_state state)
851 struct self_test *obj = addr;
854 case ODEBUG_STATE_NOTAVAILABLE:
856 case ODEBUG_STATE_ACTIVE:
857 debug_object_deactivate(obj, &descr_type_test);
858 debug_object_activate(obj, &descr_type_test);
867 * fixup_destroy is called when:
868 * - an active object is destroyed
870 static bool __init fixup_destroy(void *addr, enum debug_obj_state state)
872 struct self_test *obj = addr;
875 case ODEBUG_STATE_ACTIVE:
876 debug_object_deactivate(obj, &descr_type_test);
877 debug_object_destroy(obj, &descr_type_test);
885 * fixup_free is called when:
886 * - an active object is freed
888 static bool __init fixup_free(void *addr, enum debug_obj_state state)
890 struct self_test *obj = addr;
893 case ODEBUG_STATE_ACTIVE:
894 debug_object_deactivate(obj, &descr_type_test);
895 debug_object_free(obj, &descr_type_test);
903 check_results(void *addr, enum debug_obj_state state, int fixups, int warnings)
905 struct debug_bucket *db;
906 struct debug_obj *obj;
910 db = get_bucket((unsigned long) addr);
912 raw_spin_lock_irqsave(&db->lock, flags);
914 obj = lookup_object(addr, db);
915 if (!obj && state != ODEBUG_STATE_NONE) {
916 WARN(1, KERN_ERR "ODEBUG: selftest object not found\n");
919 if (obj && obj->state != state) {
920 WARN(1, KERN_ERR "ODEBUG: selftest wrong state: %d != %d\n",
924 if (fixups != debug_objects_fixups) {
925 WARN(1, KERN_ERR "ODEBUG: selftest fixups failed %d != %d\n",
926 fixups, debug_objects_fixups);
929 if (warnings != debug_objects_warnings) {
930 WARN(1, KERN_ERR "ODEBUG: selftest warnings failed %d != %d\n",
931 warnings, debug_objects_warnings);
936 raw_spin_unlock_irqrestore(&db->lock, flags);
938 debug_objects_enabled = 0;
942 static __initdata struct debug_obj_descr descr_type_test = {
944 .is_static_object = is_static_object,
945 .fixup_init = fixup_init,
946 .fixup_activate = fixup_activate,
947 .fixup_destroy = fixup_destroy,
948 .fixup_free = fixup_free,
951 static __initdata struct self_test obj = { .static_init = 0 };
953 static void __init debug_objects_selftest(void)
955 int fixups, oldfixups, warnings, oldwarnings;
958 local_irq_save(flags);
960 fixups = oldfixups = debug_objects_fixups;
961 warnings = oldwarnings = debug_objects_warnings;
962 descr_test = &descr_type_test;
964 debug_object_init(&obj, &descr_type_test);
965 if (check_results(&obj, ODEBUG_STATE_INIT, fixups, warnings))
967 debug_object_activate(&obj, &descr_type_test);
968 if (check_results(&obj, ODEBUG_STATE_ACTIVE, fixups, warnings))
970 debug_object_activate(&obj, &descr_type_test);
971 if (check_results(&obj, ODEBUG_STATE_ACTIVE, ++fixups, ++warnings))
973 debug_object_deactivate(&obj, &descr_type_test);
974 if (check_results(&obj, ODEBUG_STATE_INACTIVE, fixups, warnings))
976 debug_object_destroy(&obj, &descr_type_test);
977 if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, warnings))
979 debug_object_init(&obj, &descr_type_test);
980 if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, ++warnings))
982 debug_object_activate(&obj, &descr_type_test);
983 if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, ++warnings))
985 debug_object_deactivate(&obj, &descr_type_test);
986 if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, ++warnings))
988 debug_object_free(&obj, &descr_type_test);
989 if (check_results(&obj, ODEBUG_STATE_NONE, fixups, warnings))
993 debug_object_activate(&obj, &descr_type_test);
994 if (check_results(&obj, ODEBUG_STATE_ACTIVE, fixups, warnings))
996 debug_object_init(&obj, &descr_type_test);
997 if (check_results(&obj, ODEBUG_STATE_INIT, ++fixups, ++warnings))
999 debug_object_free(&obj, &descr_type_test);
1000 if (check_results(&obj, ODEBUG_STATE_NONE, fixups, warnings))
1003 #ifdef CONFIG_DEBUG_OBJECTS_FREE
1004 debug_object_init(&obj, &descr_type_test);
1005 if (check_results(&obj, ODEBUG_STATE_INIT, fixups, warnings))
1007 debug_object_activate(&obj, &descr_type_test);
1008 if (check_results(&obj, ODEBUG_STATE_ACTIVE, fixups, warnings))
1010 __debug_check_no_obj_freed(&obj, sizeof(obj));
1011 if (check_results(&obj, ODEBUG_STATE_NONE, ++fixups, ++warnings))
1014 pr_info("selftest passed\n");
1017 debug_objects_fixups = oldfixups;
1018 debug_objects_warnings = oldwarnings;
1021 local_irq_restore(flags);
1024 static inline void debug_objects_selftest(void) { }
1028 * Called during early boot to initialize the hash buckets and link
1029 * the static object pool objects into the poll list. After this call
1030 * the object tracker is fully operational.
1032 void __init debug_objects_early_init(void)
1036 for (i = 0; i < ODEBUG_HASH_SIZE; i++)
1037 raw_spin_lock_init(&obj_hash[i].lock);
1039 for (i = 0; i < ODEBUG_POOL_SIZE; i++)
1040 hlist_add_head(&obj_static_pool[i].node, &obj_pool);
1044 * Convert the statically allocated objects to dynamic ones:
1046 static int __init debug_objects_replace_static_objects(void)
1048 struct debug_bucket *db = obj_hash;
1049 struct hlist_node *tmp;
1050 struct debug_obj *obj, *new;
1051 HLIST_HEAD(objects);
1054 for (i = 0; i < ODEBUG_POOL_SIZE; i++) {
1055 obj = kmem_cache_zalloc(obj_cache, GFP_KERNEL);
1058 hlist_add_head(&obj->node, &objects);
1062 * When debug_objects_mem_init() is called we know that only
1063 * one CPU is up, so disabling interrupts is enough
1064 * protection. This avoids the lockdep hell of lock ordering.
1066 local_irq_disable();
1068 /* Remove the statically allocated objects from the pool */
1069 hlist_for_each_entry_safe(obj, tmp, &obj_pool, node)
1070 hlist_del(&obj->node);
1071 /* Move the allocated objects to the pool */
1072 hlist_move_list(&objects, &obj_pool);
1074 /* Replace the active object references */
1075 for (i = 0; i < ODEBUG_HASH_SIZE; i++, db++) {
1076 hlist_move_list(&db->list, &objects);
1078 hlist_for_each_entry(obj, &objects, node) {
1079 new = hlist_entry(obj_pool.first, typeof(*obj), node);
1080 hlist_del(&new->node);
1081 /* copy object data */
1083 hlist_add_head(&new->node, &db->list);
1089 pr_debug("%d of %d active objects replaced\n",
1090 cnt, obj_pool_used);
1093 hlist_for_each_entry_safe(obj, tmp, &objects, node) {
1094 hlist_del(&obj->node);
1095 kmem_cache_free(obj_cache, obj);
1101 * Called after the kmem_caches are functional to setup a dedicated
1102 * cache pool, which has the SLAB_DEBUG_OBJECTS flag set. This flag
1103 * prevents that the debug code is called on kmem_cache_free() for the
1104 * debug tracker objects to avoid recursive calls.
1106 void __init debug_objects_mem_init(void)
1108 if (!debug_objects_enabled)
1111 obj_cache = kmem_cache_create("debug_objects_cache",
1112 sizeof (struct debug_obj), 0,
1113 SLAB_DEBUG_OBJECTS | SLAB_NOLEAKTRACE,
1116 if (!obj_cache || debug_objects_replace_static_objects()) {
1117 debug_objects_enabled = 0;
1119 kmem_cache_destroy(obj_cache);
1120 pr_warn("out of memory.\n");
1122 debug_objects_selftest();