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-rw-r--r--kernel/lib/debugobjects.c1100
1 files changed, 1100 insertions, 0 deletions
diff --git a/kernel/lib/debugobjects.c b/kernel/lib/debugobjects.c
new file mode 100644
index 000000000..8fcdbc2fc
--- /dev/null
+++ b/kernel/lib/debugobjects.c
@@ -0,0 +1,1100 @@
+/*
+ * 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
+ */
+
+#define pr_fmt(fmt) "ODEBUG: " fmt
+
+#include <linux/debugobjects.h>
+#include <linux/interrupt.h>
+#include <linux/sched.h>
+#include <linux/seq_file.h>
+#include <linux/debugfs.h>
+#include <linux/slab.h>
+#include <linux/hash.h>
+
+#define ODEBUG_HASH_BITS 14
+#define ODEBUG_HASH_SIZE (1 << ODEBUG_HASH_BITS)
+
+#define ODEBUG_POOL_SIZE 512
+#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;
+ raw_spinlock_t lock;
+};
+
+static struct debug_bucket obj_hash[ODEBUG_HASH_SIZE];
+
+static struct debug_obj obj_static_pool[ODEBUG_POOL_SIZE] __initdata;
+
+static DEFINE_RAW_SPINLOCK(pool_lock);
+
+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;
+static int debug_objects_enabled __read_mostly
+ = CONFIG_DEBUG_OBJECTS_ENABLE_DEFAULT;
+
+static struct debug_obj_descr *descr_test __read_mostly;
+
+static void free_obj_work(struct work_struct *work);
+static DECLARE_WORK(debug_obj_work, free_obj_work);
+
+static int __init enable_object_debug(char *str)
+{
+ debug_objects_enabled = 1;
+ return 0;
+}
+
+static int __init disable_object_debug(char *str)
+{
+ debug_objects_enabled = 0;
+ return 0;
+}
+
+early_param("debug_objects", enable_object_debug);
+early_param("no_debug_objects", disable_object_debug);
+
+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",
+};
+
+static void fill_pool(void)
+{
+ gfp_t gfp = GFP_ATOMIC | __GFP_NORETRY | __GFP_NOWARN;
+ struct debug_obj *new;
+ unsigned long flags;
+
+ if (likely(obj_pool_free >= ODEBUG_POOL_MIN_LEVEL))
+ return;
+
+ if (unlikely(!obj_cache))
+ return;
+
+ while (obj_pool_free < ODEBUG_POOL_MIN_LEVEL) {
+
+ new = kmem_cache_zalloc(obj_cache, gfp);
+ if (!new)
+ return;
+
+ raw_spin_lock_irqsave(&pool_lock, flags);
+ hlist_add_head(&new->node, &obj_pool);
+ obj_pool_free++;
+ raw_spin_unlock_irqrestore(&pool_lock, flags);
+ }
+}
+
+/*
+ * Lookup an object in the hash bucket.
+ */
+static struct debug_obj *lookup_object(void *addr, struct debug_bucket *b)
+{
+ struct debug_obj *obj;
+ int cnt = 0;
+
+ hlist_for_each_entry(obj, &b->list, node) {
+ cnt++;
+ if (obj->object == addr)
+ return obj;
+ }
+ if (cnt > debug_objects_maxchain)
+ debug_objects_maxchain = cnt;
+
+ return NULL;
+}
+
+/*
+ * Allocate a new object. If the pool is empty, switch off the debugger.
+ * Must be called with interrupts disabled.
+ */
+static struct debug_obj *
+alloc_object(void *addr, struct debug_bucket *b, struct debug_obj_descr *descr)
+{
+ struct debug_obj *obj = NULL;
+
+ raw_spin_lock(&pool_lock);
+ if (obj_pool.first) {
+ obj = hlist_entry(obj_pool.first, typeof(*obj), node);
+
+ obj->object = addr;
+ obj->descr = descr;
+ obj->state = ODEBUG_STATE_NONE;
+ obj->astate = 0;
+ 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;
+ }
+ raw_spin_unlock(&pool_lock);
+
+ return obj;
+}
+
+/*
+ * workqueue function to free objects.
+ */
+static void free_obj_work(struct work_struct *work)
+{
+ struct debug_obj *obj;
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&pool_lock, flags);
+ 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.
+ */
+ raw_spin_unlock_irqrestore(&pool_lock, flags);
+ kmem_cache_free(obj_cache, obj);
+ raw_spin_lock_irqsave(&pool_lock, flags);
+ }
+ raw_spin_unlock_irqrestore(&pool_lock, flags);
+}
+
+/*
+ * 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;
+
+ raw_spin_lock_irqsave(&pool_lock, flags);
+ /*
+ * schedule work when the pool is filled and the cache is
+ * initialized:
+ */
+ if (obj_pool_free > ODEBUG_POOL_SIZE && obj_cache)
+ sched = keventd_up();
+ hlist_add_head(&obj->node, &obj_pool);
+ obj_pool_free++;
+ obj_pool_used--;
+ raw_spin_unlock_irqrestore(&pool_lock, flags);
+ if (sched)
+ schedule_work(&debug_obj_work);
+}
+
+/*
+ * 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;
+ struct hlist_node *tmp;
+ HLIST_HEAD(freelist);
+ struct debug_obj *obj;
+ unsigned long flags;
+ int i;
+
+ pr_warn("Out of memory. ODEBUG disabled\n");
+
+ for (i = 0; i < ODEBUG_HASH_SIZE; i++, db++) {
+ raw_spin_lock_irqsave(&db->lock, flags);
+ hlist_move_list(&db->list, &freelist);
+ raw_spin_unlock_irqrestore(&db->lock, flags);
+
+ /* Now free them */
+ hlist_for_each_entry_safe(obj, tmp, &freelist, node) {
+ hlist_del(&obj->node);
+ free_object(obj);
+ }
+ }
+}
+
+/*
+ * 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)
+{
+ struct debug_obj_descr *descr = obj->descr;
+ static int limit;
+
+ if (limit < 5 && descr != descr_test) {
+ void *hint = descr->debug_hint ?
+ descr->debug_hint(obj->object) : NULL;
+ limit++;
+ WARN(1, KERN_ERR "ODEBUG: %s %s (active state %u) "
+ "object type: %s hint: %pS\n",
+ msg, obj_states[obj->state], obj->astate,
+ descr->name, hint);
+ }
+ debug_objects_warnings++;
+}
+
+/*
+ * Try to repair the damage, so we have a better chance to get useful
+ * debug output.
+ */
+static int
+debug_object_fixup(int (*fixup)(void *addr, enum debug_obj_state state),
+ void * addr, enum debug_obj_state state)
+{
+ int fixed = 0;
+
+ if (fixup)
+ fixed = fixup(addr, state);
+ debug_objects_fixups += fixed;
+ return fixed;
+}
+
+static void debug_object_is_on_stack(void *addr, int onstack)
+{
+ int is_on_stack;
+ static int limit;
+
+ if (limit > 4)
+ return;
+
+ is_on_stack = object_is_on_stack(addr);
+ if (is_on_stack == onstack)
+ return;
+
+ limit++;
+ if (is_on_stack)
+ pr_warn("object is on stack, but not annotated\n");
+ else
+ pr_warn("object is not on stack, but annotated\n");
+ 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;
+
+#ifdef CONFIG_PREEMPT_RT_FULL
+ if (preempt_count() == 0 && !irqs_disabled())
+#endif
+ fill_pool();
+
+ db = get_bucket((unsigned long) addr);
+
+ raw_spin_lock_irqsave(&db->lock, flags);
+
+ obj = lookup_object(addr, db);
+ if (!obj) {
+ obj = alloc_object(addr, db, descr);
+ if (!obj) {
+ debug_objects_enabled = 0;
+ raw_spin_unlock_irqrestore(&db->lock, flags);
+ 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;
+ raw_spin_unlock_irqrestore(&db->lock, flags);
+ debug_object_fixup(descr->fixup_init, addr, state);
+ return;
+
+ case ODEBUG_STATE_DESTROYED:
+ debug_print_object(obj, "init");
+ break;
+ default:
+ break;
+ }
+
+ raw_spin_unlock_irqrestore(&db->lock, flags);
+}
+
+/**
+ * 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);
+}
+
+/**
+ * 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);
+}
+
+/**
+ * debug_object_activate - debug checks when an object is activated
+ * @addr: address of the object
+ * @descr: pointer to an object specific debug description structure
+ * Returns 0 for success, -EINVAL for check failed.
+ */
+int debug_object_activate(void *addr, struct debug_obj_descr *descr)
+{
+ enum debug_obj_state state;
+ struct debug_bucket *db;
+ struct debug_obj *obj;
+ unsigned long flags;
+ int ret;
+ struct debug_obj o = { .object = addr,
+ .state = ODEBUG_STATE_NOTAVAILABLE,
+ .descr = descr };
+
+ if (!debug_objects_enabled)
+ return 0;
+
+ 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_INIT:
+ case ODEBUG_STATE_INACTIVE:
+ obj->state = ODEBUG_STATE_ACTIVE;
+ ret = 0;
+ break;
+
+ case ODEBUG_STATE_ACTIVE:
+ debug_print_object(obj, "activate");
+ state = obj->state;
+ raw_spin_unlock_irqrestore(&db->lock, flags);
+ ret = debug_object_fixup(descr->fixup_activate, addr, state);
+ return ret ? -EINVAL : 0;
+
+ case ODEBUG_STATE_DESTROYED:
+ debug_print_object(obj, "activate");
+ ret = -EINVAL;
+ break;
+ default:
+ ret = 0;
+ break;
+ }
+ raw_spin_unlock_irqrestore(&db->lock, flags);
+ return ret;
+ }
+
+ raw_spin_unlock_irqrestore(&db->lock, flags);
+ /*
+ * This happens when a static object is activated. We
+ * let the type specific code decide whether this is
+ * true or not.
+ */
+ if (debug_object_fixup(descr->fixup_activate, addr,
+ ODEBUG_STATE_NOTAVAILABLE)) {
+ debug_print_object(&o, "activate");
+ return -EINVAL;
+ }
+ return 0;
+}
+
+/**
+ * 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);
+
+ raw_spin_lock_irqsave(&db->lock, flags);
+
+ obj = lookup_object(addr, db);
+ if (obj) {
+ switch (obj->state) {
+ case ODEBUG_STATE_INIT:
+ case ODEBUG_STATE_INACTIVE:
+ case ODEBUG_STATE_ACTIVE:
+ if (!obj->astate)
+ obj->state = ODEBUG_STATE_INACTIVE;
+ else
+ debug_print_object(obj, "deactivate");
+ 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");
+ }
+
+ raw_spin_unlock_irqrestore(&db->lock, flags);
+}
+
+/**
+ * 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);
+
+ raw_spin_lock_irqsave(&db->lock, flags);
+
+ 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;
+ raw_spin_unlock_irqrestore(&db->lock, flags);
+ debug_object_fixup(descr->fixup_destroy, addr, state);
+ return;
+
+ case ODEBUG_STATE_DESTROYED:
+ debug_print_object(obj, "destroy");
+ break;
+ default:
+ break;
+ }
+out_unlock:
+ raw_spin_unlock_irqrestore(&db->lock, flags);
+}
+
+/**
+ * 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);
+
+ raw_spin_lock_irqsave(&db->lock, flags);
+
+ 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;
+ raw_spin_unlock_irqrestore(&db->lock, flags);
+ debug_object_fixup(descr->fixup_free, addr, state);
+ return;
+ default:
+ hlist_del(&obj->node);
+ raw_spin_unlock_irqrestore(&db->lock, flags);
+ free_object(obj);
+ return;
+ }
+out_unlock:
+ raw_spin_unlock_irqrestore(&db->lock, flags);
+}
+
+/**
+ * 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);
+ /*
+ * Maybe the object is static. Let the type specific
+ * code decide what to do.
+ */
+ if (debug_object_fixup(descr->fixup_assert_init, addr,
+ ODEBUG_STATE_NOTAVAILABLE))
+ debug_print_object(&o, "assert_init");
+ return;
+ }
+
+ raw_spin_unlock_irqrestore(&db->lock, flags);
+}
+
+/**
+ * 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);
+}
+
+#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;
+ struct hlist_node *tmp;
+ HLIST_HEAD(freelist);
+ 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;
+ raw_spin_lock_irqsave(&db->lock, flags);
+ hlist_for_each_entry_safe(obj, tmp, &db->list, node) {
+ 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;
+ raw_spin_unlock_irqrestore(&db->lock, flags);
+ debug_object_fixup(descr->fixup_free,
+ (void *) oaddr, state);
+ goto repeat;
+ default:
+ hlist_del(&obj->node);
+ hlist_add_head(&obj->node, &freelist);
+ break;
+ }
+ }
+ raw_spin_unlock_irqrestore(&db->lock, flags);
+
+ /* Now free them */
+ hlist_for_each_entry_safe(obj, tmp, &freelist, node) {
+ hlist_del(&obj->node);
+ free_object(obj);
+ }
+
+ 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\n", debug_objects_maxchain);
+ seq_printf(m, "warnings :%d\n", debug_objects_warnings);
+ seq_printf(m, "fixups :%d\n", debug_objects_fixups);
+ seq_printf(m, "pool_free :%d\n", obj_pool_free);
+ seq_printf(m, "pool_min_free :%d\n", obj_pool_min_free);
+ seq_printf(m, "pool_used :%d\n", obj_pool_used);
+ seq_printf(m, "pool_max_used :%d\n", 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;
+
+/*
+ * fixup_init is called when:
+ * - an active object is initialized
+ */
+static int __init fixup_init(void *addr, enum debug_obj_state state)
+{
+ 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);
+ return 1;
+ default:
+ return 0;
+ }
+}
+
+/*
+ * fixup_activate is called when:
+ * - an active object is activated
+ * - an unknown object is activated (might be a statically initialized object)
+ */
+static int __init fixup_activate(void *addr, enum debug_obj_state state)
+{
+ struct self_test *obj = addr;
+
+ switch (state) {
+ case ODEBUG_STATE_NOTAVAILABLE:
+ if (obj->static_init == 1) {
+ debug_object_init(obj, &descr_type_test);
+ debug_object_activate(obj, &descr_type_test);
+ return 0;
+ }
+ return 1;
+
+ case ODEBUG_STATE_ACTIVE:
+ debug_object_deactivate(obj, &descr_type_test);
+ debug_object_activate(obj, &descr_type_test);
+ return 1;
+
+ default:
+ return 0;
+ }
+}
+
+/*
+ * fixup_destroy is called when:
+ * - an active object is destroyed
+ */
+static int __init fixup_destroy(void *addr, enum debug_obj_state state)
+{
+ 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);
+ return 1;
+ default:
+ return 0;
+ }
+}
+
+/*
+ * fixup_free is called when:
+ * - an active object is freed
+ */
+static int __init fixup_free(void *addr, enum debug_obj_state state)
+{
+ 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);
+ return 1;
+ default:
+ return 0;
+ }
+}
+
+static int __init
+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);
+
+ raw_spin_lock_irqsave(&db->lock, flags);
+
+ obj = lookup_object(addr, db);
+ if (!obj && state != ODEBUG_STATE_NONE) {
+ WARN(1, KERN_ERR "ODEBUG: selftest object not found\n");
+ goto out;
+ }
+ if (obj && obj->state != state) {
+ WARN(1, KERN_ERR "ODEBUG: selftest wrong state: %d != %d\n",
+ obj->state, state);
+ goto out;
+ }
+ if (fixups != debug_objects_fixups) {
+ WARN(1, KERN_ERR "ODEBUG: selftest fixups failed %d != %d\n",
+ fixups, debug_objects_fixups);
+ goto out;
+ }
+ if (warnings != debug_objects_warnings) {
+ WARN(1, KERN_ERR "ODEBUG: selftest warnings failed %d != %d\n",
+ warnings, debug_objects_warnings);
+ goto out;
+ }
+ res = 0;
+out:
+ raw_spin_unlock_irqrestore(&db->lock, flags);
+ if (res)
+ debug_objects_enabled = 0;
+ return res;
+}
+
+static __initdata struct debug_obj_descr descr_type_test = {
+ .name = "selftest",
+ .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);
+ if (check_results(&obj, ODEBUG_STATE_ACTIVE, fixups, warnings))
+ 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
+ pr_info("selftest passed\n");
+
+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++)
+ raw_spin_lock_init(&obj_hash[i].lock);
+
+ for (i = 0; i < ODEBUG_POOL_SIZE; i++)
+ hlist_add_head(&obj_static_pool[i].node, &obj_pool);
+}
+
+/*
+ * Convert the statically allocated objects to dynamic ones:
+ */
+static int __init debug_objects_replace_static_objects(void)
+{
+ struct debug_bucket *db = obj_hash;
+ struct hlist_node *tmp;
+ 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 */
+ hlist_for_each_entry_safe(obj, tmp, &obj_pool, node)
+ 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);
+
+ hlist_for_each_entry(obj, &objects, node) {
+ 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++;
+ }
+ }
+ local_irq_enable();
+
+ pr_debug("%d of %d active objects replaced\n",
+ cnt, obj_pool_used);
+ return 0;
+free:
+ hlist_for_each_entry_safe(obj, tmp, &objects, node) {
+ hlist_del(&obj->node);
+ kmem_cache_free(obj_cache, obj);
+ }
+ return -ENOMEM;
+}
+
+/*
+ * 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);
+
+ if (!obj_cache || debug_objects_replace_static_objects()) {
+ debug_objects_enabled = 0;
+ if (obj_cache)
+ kmem_cache_destroy(obj_cache);
+ pr_warn("out of memory.\n");
+ } else
+ debug_objects_selftest();
+}