/* * kernel/mutex-debug.c * * Debugging code for mutexes * * Started by Ingo Molnar: * * Copyright (C) 2004, 2005, 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com> * * lock debugging, locking tree, deadlock detection started by: * * Copyright (C) 2004, LynuxWorks, Inc., Igor Manyilov, Bill Huey * Released under the General Public License (GPL). */#include <linux/mutex.h>#include <linux/sched.h>#include <linux/delay.h>#include <linux/module.h>#include <linux/poison.h>#include <linux/spinlock.h>#include <linux/kallsyms.h>#include <linux/interrupt.h>#include <linux/debug_locks.h> #include "mutex-debug.h" /* * Must be called with lock->wait_lock held. */void debug_mutex_set_owner(struct mutex *lock, struct thread_info *new_owner){ lock->owner = new_owner;} void debug_mutex_lock_common(struct mutex *lock, struct mutex_waiter *waiter){ memset(waiter, MUTEX_DEBUG_INIT, sizeof(*waiter)); waiter->magic = waiter; INIT_LIST_HEAD(&waiter->list);} void debug_mutex_wake_waiter(struct mutex *lock, struct mutex_waiter *waiter){ SMP_DEBUG_LOCKS_WARN_ON(!spin_is_locked(&lock->wait_lock)); DEBUG_LOCKS_WARN_ON(list_empty(&lock->wait_list)); DEBUG_LOCKS_WARN_ON(waiter->magic != waiter); DEBUG_LOCKS_WARN_ON(list_empty(&waiter->list));} void debug_mutex_free_waiter(struct mutex_waiter *waiter){ DEBUG_LOCKS_WARN_ON(!list_empty(&waiter->list)); memset(waiter, MUTEX_DEBUG_FREE, sizeof(*waiter));} void debug_mutex_add_waiter(struct mutex *lock, struct mutex_waiter *waiter, struct thread_info *ti){ SMP_DEBUG_LOCKS_WARN_ON(!spin_is_locked(&lock->wait_lock)); /* Mark the current thread as blocked on the lock: */ ti->task->blocked_on = waiter; waiter->lock = lock;} void mutex_remove_waiter(struct mutex *lock, struct mutex_waiter *waiter, struct thread_info *ti){ DEBUG_LOCKS_WARN_ON(list_empty(&waiter->list)); DEBUG_LOCKS_WARN_ON(waiter->task != ti->task); DEBUG_LOCKS_WARN_ON(ti->task->blocked_on != waiter); ti->task->blocked_on = NULL; list_del_init(&waiter->list); waiter->task = NULL;} void debug_mutex_unlock(struct mutex *lock){ if (unlikely(!debug_locks)) return; DEBUG_LOCKS_WARN_ON(lock->owner != current_thread_info()); DEBUG_LOCKS_WARN_ON(lock->magic != lock); DEBUG_LOCKS_WARN_ON(!lock->wait_list.prev && !lock->wait_list.next); DEBUG_LOCKS_WARN_ON(lock->owner != current_thread_info());} void debug_mutex_init(struct mutex *lock, const char *name, struct lock_class_key *key){#ifdef CONFIG_DEBUG_LOCK_ALLOC /* * Make sure we are not reinitializing a held lock: */ debug_check_no_locks_freed((void *)lock, sizeof(*lock)); lockdep_init_map(&lock->dep_map, name, key, 0);#endif lock->owner = NULL; lock->magic = lock;} /*** * mutex_destroy - mark a mutex unusable * @lock: the mutex to be destroyed * * This function marks the mutex uninitialized, and any subsequent * use of the mutex is forbidden. The mutex must not be locked when * this function is called. */void fastcall mutex_destroy(struct mutex *lock){ DEBUG_LOCKS_WARN_ON(mutex_is_locked(lock)); lock->magic = NULL;} EXPORT_SYMBOL_GPL(mutex_destroy);
/*
* kernel/mutex-debug.c
*
* Debugging code for mutexes
*
* Started by Ingo Molnar:
*
* Copyright (C) 2004, 2005, 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
*
* lock debugging, locking tree, deadlock detection started by:
*
* Copyright (C) 2004, LynuxWorks, Inc., Igor Manyilov, Bill Huey
* Released under the General Public License (GPL).
*/
#include <linux/mutex.h>
#include <linux/sched.h>
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/poison.h>
#include <linux/spinlock.h>
#include <linux/kallsyms.h>
#include <linux/interrupt.h>
#include <linux/debug_locks.h>
#include "mutex-debug.h"
/*
* Must be called with lock->wait_lock held.
*/
void debug_mutex_set_owner(struct mutex *lock, struct thread_info *new_owner)
{
lock->owner = new_owner;
}
void debug_mutex_lock_common(struct mutex *lock, struct mutex_waiter *waiter)
{
memset(waiter, MUTEX_DEBUG_INIT, sizeof(*waiter));
waiter->magic = waiter;
INIT_LIST_HEAD(&waiter->list);
}
void debug_mutex_wake_waiter(struct mutex *lock, struct mutex_waiter *waiter)
{
SMP_DEBUG_LOCKS_WARN_ON(!spin_is_locked(&lock->wait_lock));
DEBUG_LOCKS_WARN_ON(list_empty(&lock->wait_list));
DEBUG_LOCKS_WARN_ON(waiter->magic != waiter);
DEBUG_LOCKS_WARN_ON(list_empty(&waiter->list));
}
void debug_mutex_free_waiter(struct mutex_waiter *waiter)
{
DEBUG_LOCKS_WARN_ON(!list_empty(&waiter->list));
memset(waiter, MUTEX_DEBUG_FREE, sizeof(*waiter));
}
void debug_mutex_add_waiter(struct mutex *lock, struct mutex_waiter *waiter,
struct thread_info *ti)
{
SMP_DEBUG_LOCKS_WARN_ON(!spin_is_locked(&lock->wait_lock));
/* Mark the current thread as blocked on the lock: */
ti->task->blocked_on = waiter;
waiter->lock = lock;
}
void mutex_remove_waiter(struct mutex *lock, struct mutex_waiter *waiter,
struct thread_info *ti)
{
DEBUG_LOCKS_WARN_ON(list_empty(&waiter->list));
DEBUG_LOCKS_WARN_ON(waiter->task != ti->task);
DEBUG_LOCKS_WARN_ON(ti->task->blocked_on != waiter);
ti->task->blocked_on = NULL;
list_del_init(&waiter->list);
waiter->task = NULL;
}
void debug_mutex_unlock(struct mutex *lock)
{
if (unlikely(!debug_locks))
return;
DEBUG_LOCKS_WARN_ON(lock->owner != current_thread_info());
DEBUG_LOCKS_WARN_ON(lock->magic != lock);
DEBUG_LOCKS_WARN_ON(!lock->wait_list.prev && !lock->wait_list.next);
DEBUG_LOCKS_WARN_ON(lock->owner != current_thread_info());
}
void debug_mutex_init(struct mutex *lock, const char *name,
struct lock_class_key *key)
{
#ifdef CONFIG_DEBUG_LOCK_ALLOC
/*
* Make sure we are not reinitializing a held lock:
*/
debug_check_no_locks_freed((void *)lock, sizeof(*lock));
lockdep_init_map(&lock->dep_map, name, key, 0);
#endif
lock->owner = NULL;
lock->magic = lock;
}
/***
* mutex_destroy - mark a mutex unusable
* @lock: the mutex to be destroyed
*
* This function marks the mutex uninitialized, and any subsequent
* use of the mutex is forbidden. The mutex must not be locked when
* this function is called.
*/
void fastcall mutex_destroy(struct mutex *lock)
{
DEBUG_LOCKS_WARN_ON(mutex_is_locked(lock));
lock->magic = NULL;
}
EXPORT_SYMBOL_GPL(mutex_destroy);