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lib/debugobjects.c
26.9 KB
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/* * Generic infrastructure for lifetime debugging of objects. * * Started by Thomas Gleixner * * Copyright (C) 2008, Thomas Gleixner <tglx@linutronix.de> * * For licencing details see kernel-base/COPYING */ |
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#define pr_fmt(fmt) "ODEBUG: " fmt |
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#include <linux/debugobjects.h> #include <linux/interrupt.h> |
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#include <linux/sched.h> |
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#include <linux/seq_file.h> #include <linux/debugfs.h> |
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#include <linux/slab.h> |
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#include <linux/hash.h> #define ODEBUG_HASH_BITS 14 #define ODEBUG_HASH_SIZE (1 << ODEBUG_HASH_BITS) |
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#define ODEBUG_POOL_SIZE 1024 |
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#define ODEBUG_POOL_MIN_LEVEL 256 #define ODEBUG_CHUNK_SHIFT PAGE_SHIFT #define ODEBUG_CHUNK_SIZE (1 << ODEBUG_CHUNK_SHIFT) #define ODEBUG_CHUNK_MASK (~(ODEBUG_CHUNK_SIZE - 1)) struct debug_bucket { struct hlist_head list; |
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raw_spinlock_t lock; |
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}; static struct debug_bucket obj_hash[ODEBUG_HASH_SIZE]; |
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static struct debug_obj obj_static_pool[ODEBUG_POOL_SIZE] __initdata; |
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static DEFINE_RAW_SPINLOCK(pool_lock); |
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static HLIST_HEAD(obj_pool); static int obj_pool_min_free = ODEBUG_POOL_SIZE; static int obj_pool_free = ODEBUG_POOL_SIZE; static int obj_pool_used; static int obj_pool_max_used; static struct kmem_cache *obj_cache; static int debug_objects_maxchain __read_mostly; static int debug_objects_fixups __read_mostly; static int debug_objects_warnings __read_mostly; |
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static int debug_objects_enabled __read_mostly = CONFIG_DEBUG_OBJECTS_ENABLE_DEFAULT; |
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static struct debug_obj_descr *descr_test __read_mostly; |
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static void free_obj_work(struct work_struct *work); static DECLARE_WORK(debug_obj_work, free_obj_work); |
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static int __init enable_object_debug(char *str) { debug_objects_enabled = 1; return 0; } |
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static int __init disable_object_debug(char *str) { debug_objects_enabled = 0; return 0; } |
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early_param("debug_objects", enable_object_debug); |
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early_param("no_debug_objects", disable_object_debug); |
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static const char *obj_states[ODEBUG_STATE_MAX] = { [ODEBUG_STATE_NONE] = "none", [ODEBUG_STATE_INIT] = "initialized", [ODEBUG_STATE_INACTIVE] = "inactive", [ODEBUG_STATE_ACTIVE] = "active", [ODEBUG_STATE_DESTROYED] = "destroyed", [ODEBUG_STATE_NOTAVAILABLE] = "not available", }; |
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static void fill_pool(void) |
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{ gfp_t gfp = GFP_ATOMIC | __GFP_NORETRY | __GFP_NOWARN; struct debug_obj *new; |
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unsigned long flags; |
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if (likely(obj_pool_free >= ODEBUG_POOL_MIN_LEVEL)) |
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return; |
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if (unlikely(!obj_cache)) |
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return; |
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while (obj_pool_free < ODEBUG_POOL_MIN_LEVEL) { new = kmem_cache_zalloc(obj_cache, gfp); if (!new) |
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return; |
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raw_spin_lock_irqsave(&pool_lock, flags); |
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hlist_add_head(&new->node, &obj_pool); obj_pool_free++; |
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raw_spin_unlock_irqrestore(&pool_lock, flags); |
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} |
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} /* * Lookup an object in the hash bucket. */ static struct debug_obj *lookup_object(void *addr, struct debug_bucket *b) { |
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struct debug_obj *obj; int cnt = 0; |
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hlist_for_each_entry(obj, &b->list, node) { |
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cnt++; if (obj->object == addr) return obj; } if (cnt > debug_objects_maxchain) debug_objects_maxchain = cnt; return NULL; } /* |
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* Allocate a new object. If the pool is empty, switch off the debugger. |
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* Must be called with interrupts disabled. |
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*/ static struct debug_obj * alloc_object(void *addr, struct debug_bucket *b, struct debug_obj_descr *descr) { struct debug_obj *obj = NULL; |
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raw_spin_lock(&pool_lock); |
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if (obj_pool.first) { obj = hlist_entry(obj_pool.first, typeof(*obj), node); obj->object = addr; obj->descr = descr; obj->state = ODEBUG_STATE_NONE; |
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obj->astate = 0; |
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hlist_del(&obj->node); hlist_add_head(&obj->node, &b->list); obj_pool_used++; if (obj_pool_used > obj_pool_max_used) obj_pool_max_used = obj_pool_used; obj_pool_free--; if (obj_pool_free < obj_pool_min_free) obj_pool_min_free = obj_pool_free; } |
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raw_spin_unlock(&pool_lock); |
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return obj; } /* |
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* workqueue function to free objects. |
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*/ |
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static void free_obj_work(struct work_struct *work) |
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{ |
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struct debug_obj *obj; |
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unsigned long flags; |
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raw_spin_lock_irqsave(&pool_lock, flags); |
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while (obj_pool_free > ODEBUG_POOL_SIZE) { obj = hlist_entry(obj_pool.first, typeof(*obj), node); hlist_del(&obj->node); obj_pool_free--; /* * We release pool_lock across kmem_cache_free() to * avoid contention on pool_lock. */ |
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raw_spin_unlock_irqrestore(&pool_lock, flags); |
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kmem_cache_free(obj_cache, obj); |
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raw_spin_lock_irqsave(&pool_lock, flags); |
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} |
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raw_spin_unlock_irqrestore(&pool_lock, flags); |
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} /* * Put the object back into the pool and schedule work to free objects * if necessary. */ static void free_object(struct debug_obj *obj) { unsigned long flags; int sched = 0; |
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raw_spin_lock_irqsave(&pool_lock, flags); |
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/* * schedule work when the pool is filled and the cache is * initialized: */ if (obj_pool_free > ODEBUG_POOL_SIZE && obj_cache) |
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sched = 1; |
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hlist_add_head(&obj->node, &obj_pool); obj_pool_free++; obj_pool_used--; |
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raw_spin_unlock_irqrestore(&pool_lock, flags); |
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if (sched) schedule_work(&debug_obj_work); |
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} /* * We run out of memory. That means we probably have tons of objects * allocated. */ static void debug_objects_oom(void) { struct debug_bucket *db = obj_hash; |
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struct hlist_node *tmp; |
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HLIST_HEAD(freelist); |
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struct debug_obj *obj; unsigned long flags; int i; |
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pr_warn("Out of memory. ODEBUG disabled "); |
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for (i = 0; i < ODEBUG_HASH_SIZE; i++, db++) { |
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raw_spin_lock_irqsave(&db->lock, flags); |
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hlist_move_list(&db->list, &freelist); |
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raw_spin_unlock_irqrestore(&db->lock, flags); |
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/* Now free them */ |
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hlist_for_each_entry_safe(obj, tmp, &freelist, node) { |
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hlist_del(&obj->node); free_object(obj); } |
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} } /* * We use the pfn of the address for the hash. That way we can check * for freed objects simply by checking the affected bucket. */ static struct debug_bucket *get_bucket(unsigned long addr) { unsigned long hash; hash = hash_long((addr >> ODEBUG_CHUNK_SHIFT), ODEBUG_HASH_BITS); return &obj_hash[hash]; } static void debug_print_object(struct debug_obj *obj, char *msg) { |
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struct debug_obj_descr *descr = obj->descr; |
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static int limit; |
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if (limit < 5 && descr != descr_test) { void *hint = descr->debug_hint ? descr->debug_hint(obj->object) : NULL; |
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limit++; |
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WARN(1, KERN_ERR "ODEBUG: %s %s (active state %u) " |
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"object type: %s hint: %pS ", |
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msg, obj_states[obj->state], obj->astate, |
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descr->name, hint); |
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} debug_objects_warnings++; } /* * Try to repair the damage, so we have a better chance to get useful * debug output. */ |
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static bool debug_object_fixup(bool (*fixup)(void *addr, enum debug_obj_state state), |
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void * addr, enum debug_obj_state state) { |
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if (fixup && fixup(addr, state)) { debug_objects_fixups++; return true; } return false; |
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} static void debug_object_is_on_stack(void *addr, int onstack) { |
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int is_on_stack; static int limit; if (limit > 4) return; |
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is_on_stack = object_is_on_stack(addr); |
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if (is_on_stack == onstack) return; limit++; if (is_on_stack) |
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pr_warn("object is on stack, but not annotated "); |
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else |
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pr_warn("object is not on stack, but annotated "); |
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WARN_ON(1); } static void __debug_object_init(void *addr, struct debug_obj_descr *descr, int onstack) { enum debug_obj_state state; struct debug_bucket *db; struct debug_obj *obj; unsigned long flags; |
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fill_pool(); |
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db = get_bucket((unsigned long) addr); |
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raw_spin_lock_irqsave(&db->lock, flags); |
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obj = lookup_object(addr, db); if (!obj) { obj = alloc_object(addr, db, descr); if (!obj) { debug_objects_enabled = 0; |
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raw_spin_unlock_irqrestore(&db->lock, flags); |
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debug_objects_oom(); return; } debug_object_is_on_stack(addr, onstack); } switch (obj->state) { case ODEBUG_STATE_NONE: case ODEBUG_STATE_INIT: case ODEBUG_STATE_INACTIVE: obj->state = ODEBUG_STATE_INIT; break; case ODEBUG_STATE_ACTIVE: debug_print_object(obj, "init"); state = obj->state; |
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raw_spin_unlock_irqrestore(&db->lock, flags); |
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debug_object_fixup(descr->fixup_init, addr, state); return; case ODEBUG_STATE_DESTROYED: debug_print_object(obj, "init"); break; default: break; } |
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raw_spin_unlock_irqrestore(&db->lock, flags); |
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} /** * debug_object_init - debug checks when an object is initialized * @addr: address of the object * @descr: pointer to an object specific debug description structure */ void debug_object_init(void *addr, struct debug_obj_descr *descr) { if (!debug_objects_enabled) return; __debug_object_init(addr, descr, 0); } |
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EXPORT_SYMBOL_GPL(debug_object_init); |
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/** * debug_object_init_on_stack - debug checks when an object on stack is * initialized * @addr: address of the object * @descr: pointer to an object specific debug description structure */ void debug_object_init_on_stack(void *addr, struct debug_obj_descr *descr) { if (!debug_objects_enabled) return; __debug_object_init(addr, descr, 1); } |
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EXPORT_SYMBOL_GPL(debug_object_init_on_stack); |
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/** * debug_object_activate - debug checks when an object is activated * @addr: address of the object * @descr: pointer to an object specific debug description structure |
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* Returns 0 for success, -EINVAL for check failed. |
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*/ |
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int debug_object_activate(void *addr, struct debug_obj_descr *descr) |
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{ enum debug_obj_state state; struct debug_bucket *db; struct debug_obj *obj; unsigned long flags; |
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int ret; |
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struct debug_obj o = { .object = addr, .state = ODEBUG_STATE_NOTAVAILABLE, .descr = descr }; |
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if (!debug_objects_enabled) |
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return 0; |
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db = get_bucket((unsigned long) addr); |
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raw_spin_lock_irqsave(&db->lock, flags); |
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obj = lookup_object(addr, db); if (obj) { switch (obj->state) { case ODEBUG_STATE_INIT: case ODEBUG_STATE_INACTIVE: obj->state = ODEBUG_STATE_ACTIVE; |
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ret = 0; |
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break; case ODEBUG_STATE_ACTIVE: debug_print_object(obj, "activate"); state = obj->state; |
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raw_spin_unlock_irqrestore(&db->lock, flags); |
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ret = debug_object_fixup(descr->fixup_activate, addr, state); |
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return ret ? 0 : -EINVAL; |
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case ODEBUG_STATE_DESTROYED: debug_print_object(obj, "activate"); |
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ret = -EINVAL; |
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break; default: |
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ret = 0; |
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break; } |
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raw_spin_unlock_irqrestore(&db->lock, flags); |
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return ret; |
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} |
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raw_spin_unlock_irqrestore(&db->lock, flags); |
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/* |
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* We are here when a static object is activated. We * let the type specific code confirm whether this is * true or not. if true, we just make sure that the * static object is tracked in the object tracker. If * not, this must be a bug, so we try to fix it up. |
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*/ |
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if (descr->is_static_object && descr->is_static_object(addr)) { /* track this static object */ debug_object_init(addr, descr); debug_object_activate(addr, descr); } else { |
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debug_print_object(&o, "activate"); |
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ret = debug_object_fixup(descr->fixup_activate, addr, ODEBUG_STATE_NOTAVAILABLE); return ret ? 0 : -EINVAL; |
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} return 0; |
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} |
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EXPORT_SYMBOL_GPL(debug_object_activate); |
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/** * debug_object_deactivate - debug checks when an object is deactivated * @addr: address of the object * @descr: pointer to an object specific debug description structure */ void debug_object_deactivate(void *addr, struct debug_obj_descr *descr) { struct debug_bucket *db; struct debug_obj *obj; unsigned long flags; if (!debug_objects_enabled) return; db = get_bucket((unsigned long) addr); |
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raw_spin_lock_irqsave(&db->lock, flags); |
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obj = lookup_object(addr, db); if (obj) { switch (obj->state) { case ODEBUG_STATE_INIT: case ODEBUG_STATE_INACTIVE: case ODEBUG_STATE_ACTIVE: |
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if (!obj->astate) obj->state = ODEBUG_STATE_INACTIVE; else debug_print_object(obj, "deactivate"); |
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break; case ODEBUG_STATE_DESTROYED: debug_print_object(obj, "deactivate"); break; default: break; } } else { struct debug_obj o = { .object = addr, .state = ODEBUG_STATE_NOTAVAILABLE, .descr = descr }; debug_print_object(&o, "deactivate"); } |
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raw_spin_unlock_irqrestore(&db->lock, flags); |
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} |
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EXPORT_SYMBOL_GPL(debug_object_deactivate); |
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/** * debug_object_destroy - debug checks when an object is destroyed * @addr: address of the object * @descr: pointer to an object specific debug description structure */ void debug_object_destroy(void *addr, struct debug_obj_descr *descr) { enum debug_obj_state state; struct debug_bucket *db; struct debug_obj *obj; unsigned long flags; if (!debug_objects_enabled) return; db = get_bucket((unsigned long) addr); |
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raw_spin_lock_irqsave(&db->lock, flags); |
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obj = lookup_object(addr, db); if (!obj) goto out_unlock; switch (obj->state) { case ODEBUG_STATE_NONE: case ODEBUG_STATE_INIT: case ODEBUG_STATE_INACTIVE: obj->state = ODEBUG_STATE_DESTROYED; break; case ODEBUG_STATE_ACTIVE: debug_print_object(obj, "destroy"); state = obj->state; |
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raw_spin_unlock_irqrestore(&db->lock, flags); |
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debug_object_fixup(descr->fixup_destroy, addr, state); return; case ODEBUG_STATE_DESTROYED: debug_print_object(obj, "destroy"); break; default: break; } out_unlock: |
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raw_spin_unlock_irqrestore(&db->lock, flags); |
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} |
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EXPORT_SYMBOL_GPL(debug_object_destroy); |
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/** * debug_object_free - debug checks when an object is freed * @addr: address of the object * @descr: pointer to an object specific debug description structure */ void debug_object_free(void *addr, struct debug_obj_descr *descr) { enum debug_obj_state state; struct debug_bucket *db; struct debug_obj *obj; unsigned long flags; if (!debug_objects_enabled) return; db = get_bucket((unsigned long) addr); |
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raw_spin_lock_irqsave(&db->lock, flags); |
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obj = lookup_object(addr, db); if (!obj) goto out_unlock; switch (obj->state) { case ODEBUG_STATE_ACTIVE: debug_print_object(obj, "free"); state = obj->state; |
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raw_spin_unlock_irqrestore(&db->lock, flags); |
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debug_object_fixup(descr->fixup_free, addr, state); return; default: hlist_del(&obj->node); |
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raw_spin_unlock_irqrestore(&db->lock, flags); |
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free_object(obj); |
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return; |
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} out_unlock: |
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raw_spin_unlock_irqrestore(&db->lock, flags); |
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} |
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EXPORT_SYMBOL_GPL(debug_object_free); |
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/** |
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* debug_object_assert_init - debug checks when object should be init-ed * @addr: address of the object * @descr: pointer to an object specific debug description structure */ void debug_object_assert_init(void *addr, struct debug_obj_descr *descr) { struct debug_bucket *db; struct debug_obj *obj; unsigned long flags; if (!debug_objects_enabled) return; db = get_bucket((unsigned long) addr); raw_spin_lock_irqsave(&db->lock, flags); obj = lookup_object(addr, db); if (!obj) { struct debug_obj o = { .object = addr, .state = ODEBUG_STATE_NOTAVAILABLE, .descr = descr }; raw_spin_unlock_irqrestore(&db->lock, flags); /* |
b9fdac7f6
|
599 600 601 |
* Maybe the object is static, and we let the type specific * code confirm. Track this static object if true, else invoke * fixup. |
b84d435cc
|
602 |
*/ |
b9fdac7f6
|
603 604 605 606 |
if (descr->is_static_object && descr->is_static_object(addr)) { /* Track this static object */ debug_object_init(addr, descr); } else { |
b84d435cc
|
607 |
debug_print_object(&o, "assert_init"); |
b9fdac7f6
|
608 609 610 |
debug_object_fixup(descr->fixup_assert_init, addr, ODEBUG_STATE_NOTAVAILABLE); } |
b84d435cc
|
611 612 613 614 615 |
return; } raw_spin_unlock_irqrestore(&db->lock, flags); } |
f8ff04e2b
|
616 |
EXPORT_SYMBOL_GPL(debug_object_assert_init); |
b84d435cc
|
617 618 |
/** |
a5d8e467f
|
619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 |
* debug_object_active_state - debug checks object usage state machine * @addr: address of the object * @descr: pointer to an object specific debug description structure * @expect: expected state * @next: state to move to if expected state is found */ void debug_object_active_state(void *addr, struct debug_obj_descr *descr, unsigned int expect, unsigned int next) { struct debug_bucket *db; struct debug_obj *obj; unsigned long flags; if (!debug_objects_enabled) return; db = get_bucket((unsigned long) addr); raw_spin_lock_irqsave(&db->lock, flags); obj = lookup_object(addr, db); if (obj) { switch (obj->state) { case ODEBUG_STATE_ACTIVE: if (obj->astate == expect) obj->astate = next; else debug_print_object(obj, "active_state"); break; default: debug_print_object(obj, "active_state"); break; } } else { struct debug_obj o = { .object = addr, .state = ODEBUG_STATE_NOTAVAILABLE, .descr = descr }; debug_print_object(&o, "active_state"); } raw_spin_unlock_irqrestore(&db->lock, flags); } |
f8ff04e2b
|
664 |
EXPORT_SYMBOL_GPL(debug_object_active_state); |
a5d8e467f
|
665 |
|
3ac7fe5a4
|
666 667 668 669 |
#ifdef CONFIG_DEBUG_OBJECTS_FREE static void __debug_check_no_obj_freed(const void *address, unsigned long size) { unsigned long flags, oaddr, saddr, eaddr, paddr, chunks; |
b67bfe0d4
|
670 |
struct hlist_node *tmp; |
673d62cc5
|
671 |
HLIST_HEAD(freelist); |
3ac7fe5a4
|
672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 |
struct debug_obj_descr *descr; enum debug_obj_state state; struct debug_bucket *db; struct debug_obj *obj; int cnt; saddr = (unsigned long) address; eaddr = saddr + size; paddr = saddr & ODEBUG_CHUNK_MASK; chunks = ((eaddr - paddr) + (ODEBUG_CHUNK_SIZE - 1)); chunks >>= ODEBUG_CHUNK_SHIFT; for (;chunks > 0; chunks--, paddr += ODEBUG_CHUNK_SIZE) { db = get_bucket(paddr); repeat: cnt = 0; |
aef9cb052
|
689 |
raw_spin_lock_irqsave(&db->lock, flags); |
b67bfe0d4
|
690 |
hlist_for_each_entry_safe(obj, tmp, &db->list, node) { |
3ac7fe5a4
|
691 692 693 694 695 696 697 698 699 700 |
cnt++; oaddr = (unsigned long) obj->object; if (oaddr < saddr || oaddr >= eaddr) continue; switch (obj->state) { case ODEBUG_STATE_ACTIVE: debug_print_object(obj, "free"); descr = obj->descr; state = obj->state; |
aef9cb052
|
701 |
raw_spin_unlock_irqrestore(&db->lock, flags); |
3ac7fe5a4
|
702 703 704 705 706 |
debug_object_fixup(descr->fixup_free, (void *) oaddr, state); goto repeat; default: hlist_del(&obj->node); |
673d62cc5
|
707 |
hlist_add_head(&obj->node, &freelist); |
3ac7fe5a4
|
708 709 710 |
break; } } |
aef9cb052
|
711 |
raw_spin_unlock_irqrestore(&db->lock, flags); |
673d62cc5
|
712 713 |
/* Now free them */ |
b67bfe0d4
|
714 |
hlist_for_each_entry_safe(obj, tmp, &freelist, node) { |
673d62cc5
|
715 716 717 |
hlist_del(&obj->node); free_object(obj); } |
3ac7fe5a4
|
718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 |
if (cnt > debug_objects_maxchain) debug_objects_maxchain = cnt; } } void debug_check_no_obj_freed(const void *address, unsigned long size) { if (debug_objects_enabled) __debug_check_no_obj_freed(address, size); } #endif #ifdef CONFIG_DEBUG_FS static int debug_stats_show(struct seq_file *m, void *v) { seq_printf(m, "max_chain :%d ", debug_objects_maxchain); seq_printf(m, "warnings :%d ", debug_objects_warnings); seq_printf(m, "fixups :%d ", debug_objects_fixups); seq_printf(m, "pool_free :%d ", obj_pool_free); seq_printf(m, "pool_min_free :%d ", obj_pool_min_free); seq_printf(m, "pool_used :%d ", obj_pool_used); seq_printf(m, "pool_max_used :%d ", obj_pool_max_used); return 0; } static int debug_stats_open(struct inode *inode, struct file *filp) { return single_open(filp, debug_stats_show, NULL); } static const struct file_operations debug_stats_fops = { .open = debug_stats_open, .read = seq_read, .llseek = seq_lseek, .release = single_release, }; static int __init debug_objects_init_debugfs(void) { struct dentry *dbgdir, *dbgstats; if (!debug_objects_enabled) return 0; dbgdir = debugfs_create_dir("debug_objects", NULL); if (!dbgdir) return -ENOMEM; dbgstats = debugfs_create_file("stats", 0444, dbgdir, NULL, &debug_stats_fops); if (!dbgstats) goto err; return 0; err: debugfs_remove(dbgdir); return -ENOMEM; } __initcall(debug_objects_init_debugfs); #else static inline void debug_objects_init_debugfs(void) { } #endif #ifdef CONFIG_DEBUG_OBJECTS_SELFTEST /* Random data structure for the self test */ struct self_test { unsigned long dummy1[6]; int static_init; unsigned long dummy2[3]; }; static __initdata struct debug_obj_descr descr_type_test; |
b9fdac7f6
|
802 803 804 805 806 807 |
static bool __init is_static_object(void *addr) { struct self_test *obj = addr; return obj->static_init; } |
3ac7fe5a4
|
808 809 810 811 |
/* * fixup_init is called when: * - an active object is initialized */ |
b1e4d9d82
|
812 |
static bool __init fixup_init(void *addr, enum debug_obj_state state) |
3ac7fe5a4
|
813 814 815 816 817 818 819 |
{ struct self_test *obj = addr; switch (state) { case ODEBUG_STATE_ACTIVE: debug_object_deactivate(obj, &descr_type_test); debug_object_init(obj, &descr_type_test); |
b1e4d9d82
|
820 |
return true; |
3ac7fe5a4
|
821 |
default: |
b1e4d9d82
|
822 |
return false; |
3ac7fe5a4
|
823 824 825 826 827 828 |
} } /* * fixup_activate is called when: * - an active object is activated |
b9fdac7f6
|
829 |
* - an unknown non-static object is activated |
3ac7fe5a4
|
830 |
*/ |
b1e4d9d82
|
831 |
static bool __init fixup_activate(void *addr, enum debug_obj_state state) |
3ac7fe5a4
|
832 833 834 835 836 |
{ struct self_test *obj = addr; switch (state) { case ODEBUG_STATE_NOTAVAILABLE: |
b1e4d9d82
|
837 |
return true; |
3ac7fe5a4
|
838 839 840 |
case ODEBUG_STATE_ACTIVE: debug_object_deactivate(obj, &descr_type_test); debug_object_activate(obj, &descr_type_test); |
b1e4d9d82
|
841 |
return true; |
3ac7fe5a4
|
842 843 |
default: |
b1e4d9d82
|
844 |
return false; |
3ac7fe5a4
|
845 846 847 848 849 850 851 |
} } /* * fixup_destroy is called when: * - an active object is destroyed */ |
b1e4d9d82
|
852 |
static bool __init fixup_destroy(void *addr, enum debug_obj_state state) |
3ac7fe5a4
|
853 854 855 856 857 858 859 |
{ struct self_test *obj = addr; switch (state) { case ODEBUG_STATE_ACTIVE: debug_object_deactivate(obj, &descr_type_test); debug_object_destroy(obj, &descr_type_test); |
b1e4d9d82
|
860 |
return true; |
3ac7fe5a4
|
861 |
default: |
b1e4d9d82
|
862 |
return false; |
3ac7fe5a4
|
863 864 865 866 867 868 869 |
} } /* * fixup_free is called when: * - an active object is freed */ |
b1e4d9d82
|
870 |
static bool __init fixup_free(void *addr, enum debug_obj_state state) |
3ac7fe5a4
|
871 872 873 874 875 876 877 |
{ struct self_test *obj = addr; switch (state) { case ODEBUG_STATE_ACTIVE: debug_object_deactivate(obj, &descr_type_test); debug_object_free(obj, &descr_type_test); |
b1e4d9d82
|
878 |
return true; |
3ac7fe5a4
|
879 |
default: |
b1e4d9d82
|
880 |
return false; |
3ac7fe5a4
|
881 882 |
} } |
1fb2f77c0
|
883 |
static int __init |
3ac7fe5a4
|
884 885 886 887 888 889 890 891 |
check_results(void *addr, enum debug_obj_state state, int fixups, int warnings) { struct debug_bucket *db; struct debug_obj *obj; unsigned long flags; int res = -EINVAL; db = get_bucket((unsigned long) addr); |
aef9cb052
|
892 |
raw_spin_lock_irqsave(&db->lock, flags); |
3ac7fe5a4
|
893 894 895 |
obj = lookup_object(addr, db); if (!obj && state != ODEBUG_STATE_NONE) { |
5cd2b459d
|
896 897 |
WARN(1, KERN_ERR "ODEBUG: selftest object not found "); |
3ac7fe5a4
|
898 899 900 |
goto out; } if (obj && obj->state != state) { |
5cd2b459d
|
901 902 |
WARN(1, KERN_ERR "ODEBUG: selftest wrong state: %d != %d ", |
3ac7fe5a4
|
903 |
obj->state, state); |
3ac7fe5a4
|
904 905 906 |
goto out; } if (fixups != debug_objects_fixups) { |
5cd2b459d
|
907 908 |
WARN(1, KERN_ERR "ODEBUG: selftest fixups failed %d != %d ", |
3ac7fe5a4
|
909 |
fixups, debug_objects_fixups); |
3ac7fe5a4
|
910 911 912 |
goto out; } if (warnings != debug_objects_warnings) { |
5cd2b459d
|
913 914 |
WARN(1, KERN_ERR "ODEBUG: selftest warnings failed %d != %d ", |
3ac7fe5a4
|
915 |
warnings, debug_objects_warnings); |
3ac7fe5a4
|
916 917 918 919 |
goto out; } res = 0; out: |
aef9cb052
|
920 |
raw_spin_unlock_irqrestore(&db->lock, flags); |
3ac7fe5a4
|
921 922 923 924 925 926 927 |
if (res) debug_objects_enabled = 0; return res; } static __initdata struct debug_obj_descr descr_type_test = { .name = "selftest", |
b9fdac7f6
|
928 |
.is_static_object = is_static_object, |
3ac7fe5a4
|
929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 |
.fixup_init = fixup_init, .fixup_activate = fixup_activate, .fixup_destroy = fixup_destroy, .fixup_free = fixup_free, }; static __initdata struct self_test obj = { .static_init = 0 }; static void __init debug_objects_selftest(void) { int fixups, oldfixups, warnings, oldwarnings; unsigned long flags; local_irq_save(flags); fixups = oldfixups = debug_objects_fixups; warnings = oldwarnings = debug_objects_warnings; descr_test = &descr_type_test; debug_object_init(&obj, &descr_type_test); if (check_results(&obj, ODEBUG_STATE_INIT, fixups, warnings)) goto out; debug_object_activate(&obj, &descr_type_test); if (check_results(&obj, ODEBUG_STATE_ACTIVE, fixups, warnings)) goto out; debug_object_activate(&obj, &descr_type_test); if (check_results(&obj, ODEBUG_STATE_ACTIVE, ++fixups, ++warnings)) goto out; debug_object_deactivate(&obj, &descr_type_test); if (check_results(&obj, ODEBUG_STATE_INACTIVE, fixups, warnings)) goto out; debug_object_destroy(&obj, &descr_type_test); if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, warnings)) goto out; debug_object_init(&obj, &descr_type_test); if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, ++warnings)) goto out; debug_object_activate(&obj, &descr_type_test); if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, ++warnings)) goto out; debug_object_deactivate(&obj, &descr_type_test); if (check_results(&obj, ODEBUG_STATE_DESTROYED, fixups, ++warnings)) goto out; debug_object_free(&obj, &descr_type_test); if (check_results(&obj, ODEBUG_STATE_NONE, fixups, warnings)) goto out; obj.static_init = 1; debug_object_activate(&obj, &descr_type_test); |
9f78ff005
|
978 |
if (check_results(&obj, ODEBUG_STATE_ACTIVE, fixups, warnings)) |
3ac7fe5a4
|
979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 |
goto out; debug_object_init(&obj, &descr_type_test); if (check_results(&obj, ODEBUG_STATE_INIT, ++fixups, ++warnings)) goto out; debug_object_free(&obj, &descr_type_test); if (check_results(&obj, ODEBUG_STATE_NONE, fixups, warnings)) goto out; #ifdef CONFIG_DEBUG_OBJECTS_FREE debug_object_init(&obj, &descr_type_test); if (check_results(&obj, ODEBUG_STATE_INIT, fixups, warnings)) goto out; debug_object_activate(&obj, &descr_type_test); if (check_results(&obj, ODEBUG_STATE_ACTIVE, fixups, warnings)) goto out; __debug_check_no_obj_freed(&obj, sizeof(obj)); if (check_results(&obj, ODEBUG_STATE_NONE, ++fixups, ++warnings)) goto out; #endif |
719e48439
|
998 999 |
pr_info("selftest passed "); |
3ac7fe5a4
|
1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 |
out: debug_objects_fixups = oldfixups; debug_objects_warnings = oldwarnings; descr_test = NULL; local_irq_restore(flags); } #else static inline void debug_objects_selftest(void) { } #endif /* * Called during early boot to initialize the hash buckets and link * the static object pool objects into the poll list. After this call * the object tracker is fully operational. */ void __init debug_objects_early_init(void) { int i; for (i = 0; i < ODEBUG_HASH_SIZE; i++) |
aef9cb052
|
1022 |
raw_spin_lock_init(&obj_hash[i].lock); |
3ac7fe5a4
|
1023 1024 1025 1026 1027 1028 |
for (i = 0; i < ODEBUG_POOL_SIZE; i++) hlist_add_head(&obj_static_pool[i].node, &obj_pool); } /* |
1be1cb7b4
|
1029 1030 |
* Convert the statically allocated objects to dynamic ones: */ |
1fb2f77c0
|
1031 |
static int __init debug_objects_replace_static_objects(void) |
1be1cb7b4
|
1032 1033 |
{ struct debug_bucket *db = obj_hash; |
b67bfe0d4
|
1034 |
struct hlist_node *tmp; |
1be1cb7b4
|
1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 |
struct debug_obj *obj, *new; HLIST_HEAD(objects); int i, cnt = 0; for (i = 0; i < ODEBUG_POOL_SIZE; i++) { obj = kmem_cache_zalloc(obj_cache, GFP_KERNEL); if (!obj) goto free; hlist_add_head(&obj->node, &objects); } /* * When debug_objects_mem_init() is called we know that only * one CPU is up, so disabling interrupts is enough * protection. This avoids the lockdep hell of lock ordering. */ local_irq_disable(); /* Remove the statically allocated objects from the pool */ |
b67bfe0d4
|
1054 |
hlist_for_each_entry_safe(obj, tmp, &obj_pool, node) |
1be1cb7b4
|
1055 1056 1057 1058 1059 1060 1061 |
hlist_del(&obj->node); /* Move the allocated objects to the pool */ hlist_move_list(&objects, &obj_pool); /* Replace the active object references */ for (i = 0; i < ODEBUG_HASH_SIZE; i++, db++) { hlist_move_list(&db->list, &objects); |
b67bfe0d4
|
1062 |
hlist_for_each_entry(obj, &objects, node) { |
1be1cb7b4
|
1063 1064 1065 1066 1067 1068 1069 1070 |
new = hlist_entry(obj_pool.first, typeof(*obj), node); hlist_del(&new->node); /* copy object data */ *new = *obj; hlist_add_head(&new->node, &db->list); cnt++; } } |
765a5e0cb
|
1071 |
local_irq_enable(); |
1be1cb7b4
|
1072 |
|
c0f35cc0b
|
1073 1074 1075 |
pr_debug("%d of %d active objects replaced ", cnt, obj_pool_used); |
1be1cb7b4
|
1076 1077 |
return 0; free: |
b67bfe0d4
|
1078 |
hlist_for_each_entry_safe(obj, tmp, &objects, node) { |
1be1cb7b4
|
1079 1080 1081 1082 1083 1084 1085 |
hlist_del(&obj->node); kmem_cache_free(obj_cache, obj); } return -ENOMEM; } /* |
3ac7fe5a4
|
1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 |
* Called after the kmem_caches are functional to setup a dedicated * cache pool, which has the SLAB_DEBUG_OBJECTS flag set. This flag * prevents that the debug code is called on kmem_cache_free() for the * debug tracker objects to avoid recursive calls. */ void __init debug_objects_mem_init(void) { if (!debug_objects_enabled) return; obj_cache = kmem_cache_create("debug_objects_cache", sizeof (struct debug_obj), 0, SLAB_DEBUG_OBJECTS, NULL); |
1be1cb7b4
|
1099 |
if (!obj_cache || debug_objects_replace_static_objects()) { |
3ac7fe5a4
|
1100 |
debug_objects_enabled = 0; |
1be1cb7b4
|
1101 1102 |
if (obj_cache) kmem_cache_destroy(obj_cache); |
719e48439
|
1103 1104 |
pr_warn("out of memory. "); |
1be1cb7b4
|
1105 |
} else |
3ac7fe5a4
|
1106 1107 |
debug_objects_selftest(); } |