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-rw-r--r--include/linux/lockdep.h54
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:
*/