diff options
| -rw-r--r-- | include/linux/backing-dev.h | 2 | ||||
| -rw-r--r-- | include/linux/lockdep.h | 4 | ||||
| -rw-r--r-- | include/linux/srcu.h | 4 | ||||
| -rw-r--r-- | include/net/sock.h | 4 | ||||
| -rw-r--r-- | kernel/locking/lockdep.c | 89 | 
5 files changed, 53 insertions, 50 deletions
| diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h index e54e7e0033eb..3e4ce54d84ab 100644 --- a/include/linux/backing-dev.h +++ b/include/linux/backing-dev.h @@ -332,7 +332,7 @@ static inline bool inode_to_wb_is_valid(struct inode *inode)   * holding either @inode->i_lock, @inode->i_mapping->tree_lock, or the   * associated wb's list_lock.   */ -static inline struct bdi_writeback *inode_to_wb(struct inode *inode) +static inline struct bdi_writeback *inode_to_wb(const struct inode *inode)  {  #ifdef CONFIG_LOCKDEP  	WARN_ON_ONCE(debug_locks && diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h index 795634ee5aa5..6fc77d4dbdcd 100644 --- a/include/linux/lockdep.h +++ b/include/linux/lockdep.h @@ -337,9 +337,9 @@ extern void lock_release(struct lockdep_map *lock, int nested,  /*   * Same "read" as for lock_acquire(), except -1 means any.   */ -extern int lock_is_held_type(struct lockdep_map *lock, int read); +extern int lock_is_held_type(const struct lockdep_map *lock, int read); -static inline int lock_is_held(struct lockdep_map *lock) +static inline int lock_is_held(const struct lockdep_map *lock)  {  	return lock_is_held_type(lock, -1);  } diff --git a/include/linux/srcu.h b/include/linux/srcu.h index 62be8966e837..33c1c698df09 100644 --- a/include/linux/srcu.h +++ b/include/linux/srcu.h @@ -92,7 +92,7 @@ void synchronize_srcu(struct srcu_struct *sp);   * relies on normal RCU, it can be called from the CPU which   * is in the idle loop from an RCU point of view or offline.   */ -static inline int srcu_read_lock_held(struct srcu_struct *sp) +static inline int srcu_read_lock_held(const struct srcu_struct *sp)  {  	if (!debug_lockdep_rcu_enabled())  		return 1; @@ -101,7 +101,7 @@ static inline int srcu_read_lock_held(struct srcu_struct *sp)  #else /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */ -static inline int srcu_read_lock_held(struct srcu_struct *sp) +static inline int srcu_read_lock_held(const struct srcu_struct *sp)  {  	return 1;  } diff --git a/include/net/sock.h b/include/net/sock.h index 7a7b14e9628a..c4a424fe6fdd 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -1445,10 +1445,8 @@ do {									\  } while (0)  #ifdef CONFIG_LOCKDEP -static inline bool lockdep_sock_is_held(const struct sock *csk) +static inline bool lockdep_sock_is_held(const struct sock *sk)  { -	struct sock *sk = (struct sock *)csk; -  	return lockdep_is_held(&sk->sk_lock) ||  	       lockdep_is_held(&sk->sk_lock.slock);  } diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 521659044719..89b5f83f1969 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -648,18 +648,12 @@ static int count_matching_names(struct lock_class *new_class)  	return count + 1;  } -/* - * Register a lock's class in the hash-table, if the class is not present - * yet. Otherwise we look it up. We cache the result in the lock object - * itself, so actual lookup of the hash should be once per lock object. - */  static inline struct lock_class * -look_up_lock_class(struct lockdep_map *lock, unsigned int subclass) +look_up_lock_class(const struct lockdep_map *lock, unsigned int subclass)  {  	struct lockdep_subclass_key *key;  	struct hlist_head *hash_head;  	struct lock_class *class; -	bool is_static = false;  	if (unlikely(subclass >= MAX_LOCKDEP_SUBCLASSES)) {  		debug_locks_off(); @@ -672,24 +666,11 @@ look_up_lock_class(struct lockdep_map *lock, unsigned int subclass)  	}  	/* -	 * Static locks do not have their class-keys yet - for them the key -	 * is the lock object itself. If the lock is in the per cpu area, -	 * the canonical address of the lock (per cpu offset removed) is -	 * used. +	 * If it is not initialised then it has never been locked, +	 * so it won't be present in the hash table.  	 */ -	if (unlikely(!lock->key)) { -		unsigned long can_addr, addr = (unsigned long)lock; - -		if (__is_kernel_percpu_address(addr, &can_addr)) -			lock->key = (void *)can_addr; -		else if (__is_module_percpu_address(addr, &can_addr)) -			lock->key = (void *)can_addr; -		else if (static_obj(lock)) -			lock->key = (void *)lock; -		else -			return ERR_PTR(-EINVAL); -		is_static = true; -	} +	if (unlikely(!lock->key)) +		return NULL;  	/*  	 * NOTE: the class-key must be unique. For dynamic locks, a static @@ -721,7 +702,35 @@ look_up_lock_class(struct lockdep_map *lock, unsigned int subclass)  		}  	} -	return is_static || static_obj(lock->key) ? NULL : ERR_PTR(-EINVAL); +	return NULL; +} + +/* + * Static locks do not have their class-keys yet - for them the key is + * the lock object itself. If the lock is in the per cpu area, the + * canonical address of the lock (per cpu offset removed) is used. + */ +static bool assign_lock_key(struct lockdep_map *lock) +{ +	unsigned long can_addr, addr = (unsigned long)lock; + +	if (__is_kernel_percpu_address(addr, &can_addr)) +		lock->key = (void *)can_addr; +	else if (__is_module_percpu_address(addr, &can_addr)) +		lock->key = (void *)can_addr; +	else if (static_obj(lock)) +		lock->key = (void *)lock; +	else { +		/* Debug-check: all keys must be persistent! */ +		debug_locks_off(); +		pr_err("INFO: trying to register non-static key.\n"); +		pr_err("the code is fine but needs lockdep annotation.\n"); +		pr_err("turning off the locking correctness validator.\n"); +		dump_stack(); +		return false; +	} + +	return true;  }  /* @@ -739,18 +748,13 @@ register_lock_class(struct lockdep_map *lock, unsigned int subclass, int force)  	DEBUG_LOCKS_WARN_ON(!irqs_disabled());  	class = look_up_lock_class(lock, subclass); -	if (likely(!IS_ERR_OR_NULL(class))) +	if (likely(class))  		goto out_set_class_cache; -	/* -	 * Debug-check: all keys must be persistent! -	 */ -	if (IS_ERR(class)) { -		debug_locks_off(); -		printk("INFO: trying to register non-static key.\n"); -		printk("the code is fine but needs lockdep annotation.\n"); -		printk("turning off the locking correctness validator.\n"); -		dump_stack(); +	if (!lock->key) { +		if (!assign_lock_key(lock)) +			return NULL; +	} else if (!static_obj(lock->key)) {  		return NULL;  	} @@ -3273,7 +3277,7 @@ print_lock_nested_lock_not_held(struct task_struct *curr,  	return 0;  } -static int __lock_is_held(struct lockdep_map *lock, int read); +static int __lock_is_held(const struct lockdep_map *lock, int read);  /*   * This gets called for every mutex_lock*()/spin_lock*() operation. @@ -3482,13 +3486,14 @@ print_unlock_imbalance_bug(struct task_struct *curr, struct lockdep_map *lock,  	return 0;  } -static int match_held_lock(struct held_lock *hlock, struct lockdep_map *lock) +static int match_held_lock(const struct held_lock *hlock, +					const struct lockdep_map *lock)  {  	if (hlock->instance == lock)  		return 1;  	if (hlock->references) { -		struct lock_class *class = lock->class_cache[0]; +		const struct lock_class *class = lock->class_cache[0];  		if (!class)  			class = look_up_lock_class(lock, 0); @@ -3499,7 +3504,7 @@ static int match_held_lock(struct held_lock *hlock, struct lockdep_map *lock)  		 * Clearly if the lock hasn't been acquired _ever_, we're not  		 * holding it either, so report failure.  		 */ -		if (IS_ERR_OR_NULL(class)) +		if (!class)  			return 0;  		/* @@ -3724,7 +3729,7 @@ __lock_release(struct lockdep_map *lock, int nested, unsigned long ip)  	return 1;  } -static int __lock_is_held(struct lockdep_map *lock, int read) +static int __lock_is_held(const struct lockdep_map *lock, int read)  {  	struct task_struct *curr = current;  	int i; @@ -3938,7 +3943,7 @@ void lock_release(struct lockdep_map *lock, int nested,  }  EXPORT_SYMBOL_GPL(lock_release); -int lock_is_held_type(struct lockdep_map *lock, int read) +int lock_is_held_type(const struct lockdep_map *lock, int read)  {  	unsigned long flags;  	int ret = 0; @@ -4295,7 +4300,7 @@ void lockdep_reset_lock(struct lockdep_map *lock)  		 * If the class exists we look it up and zap it:  		 */  		class = look_up_lock_class(lock, j); -		if (!IS_ERR_OR_NULL(class)) +		if (class)  			zap_class(class);  	}  	/* | 
