diff options
Diffstat (limited to 'include/linux/lockdep.h')
| -rw-r--r-- | include/linux/lockdep.h | 54 |
1 files changed, 40 insertions, 14 deletions
diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h index c5335df2372f..79c3873d58ac 100644 --- a/include/linux/lockdep.h +++ b/include/linux/lockdep.h @@ -46,16 +46,22 @@ extern int lock_stat; #define NR_LOCKDEP_CACHING_CLASSES 2 /* - * Lock-classes are keyed via unique addresses, by embedding the - * lockclass-key into the kernel (or module) .data section. (For - * static locks we use the lock address itself as the key.) + * A lockdep key is associated with each lock object. For static locks we use + * the lock address itself as the key. Dynamically allocated lock objects can + * have a statically or dynamically allocated key. Dynamically allocated lock + * keys must be registered before being used and must be unregistered before + * the key memory is freed. */ struct lockdep_subclass_key { char __one_byte; } __attribute__ ((__packed__)); +/* hash_entry is used to keep track of dynamically allocated keys. */ struct lock_class_key { - struct lockdep_subclass_key subkeys[MAX_LOCKDEP_SUBCLASSES]; + union { + struct hlist_node hash_entry; + struct lockdep_subclass_key subkeys[MAX_LOCKDEP_SUBCLASSES]; + }; }; extern struct lock_class_key __lockdep_no_validate__; @@ -63,7 +69,8 @@ extern struct lock_class_key __lockdep_no_validate__; #define LOCKSTAT_POINTS 4 /* - * The lock-class itself: + * The lock-class itself. The order of the structure members matters. + * reinit_class() zeroes the key member and all subsequent members. */ struct lock_class { /* @@ -72,10 +79,19 @@ struct lock_class { struct hlist_node hash_entry; /* - * global list of all lock-classes: + * Entry in all_lock_classes when in use. Entry in free_lock_classes + * when not in use. Instances that are being freed are on one of the + * zapped_classes lists. */ struct list_head lock_entry; + /* + * These fields represent a directed graph of lock dependencies, + * to every node we attach a list of "forward" and a list of + * "backward" graph nodes. + */ + struct list_head locks_after, locks_before; + struct lockdep_subclass_key *key; unsigned int subclass; unsigned int dep_gen_id; @@ -87,13 +103,6 @@ struct lock_class { struct stack_trace usage_traces[XXX_LOCK_USAGE_STATES]; /* - * These fields represent a directed graph of lock dependencies, - * to every node we attach a list of "forward" and a list of - * "backward" graph nodes. - */ - struct list_head locks_after, locks_before; - - /* * Generation counter, when doing certain classes of graph walking, * to ensure that we check one node only once: */ @@ -104,7 +113,7 @@ struct lock_class { unsigned long contention_point[LOCKSTAT_POINTS]; unsigned long contending_point[LOCKSTAT_POINTS]; #endif -}; +} __no_randomize_layout; #ifdef CONFIG_LOCK_STAT struct lock_time { @@ -178,6 +187,7 @@ static inline void lockdep_copy_map(struct lockdep_map *to, struct lock_list { struct list_head entry; struct lock_class *class; + struct lock_class *links_to; struct stack_trace trace; int distance; @@ -264,10 +274,14 @@ extern void lockdep_reset(void); extern void lockdep_reset_lock(struct lockdep_map *lock); extern void lockdep_free_key_range(void *start, unsigned long size); extern asmlinkage void lockdep_sys_exit(void); +extern void lockdep_set_selftest_task(struct task_struct *task); extern void lockdep_off(void); extern void lockdep_on(void); +extern void lockdep_register_key(struct lock_class_key *key); +extern void lockdep_unregister_key(struct lock_class_key *key); + /* * These methods are used by specific locking variants (spinlocks, * rwlocks, mutexes and rwsems) to pass init/acquire/release events @@ -394,6 +408,10 @@ static inline void lockdep_on(void) { } +static inline void lockdep_set_selftest_task(struct task_struct *task) +{ +} + # define lock_acquire(l, s, t, r, c, n, i) do { } while (0) # define lock_release(l, n, i) do { } while (0) # define lock_downgrade(l, i) do { } while (0) @@ -425,6 +443,14 @@ static inline void lockdep_on(void) */ struct lock_class_key { }; +static inline void lockdep_register_key(struct lock_class_key *key) +{ +} + +static inline void lockdep_unregister_key(struct lock_class_key *key) +{ +} + /* * The lockdep_map takes no space if lockdep is disabled: */ |