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-rw-r--r--include/linux/lockdep.h70
1 files changed, 60 insertions, 10 deletions
diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h
index da5a5a1f4cd2..71c09b26c759 100644
--- a/include/linux/lockdep.h
+++ b/include/linux/lockdep.h
@@ -12,6 +12,10 @@
struct task_struct;
struct lockdep_map;
+/* for sysctl */
+extern int prove_locking;
+extern int lock_stat;
+
#ifdef CONFIG_LOCKDEP
#include <linux/linkage.h>
@@ -28,6 +32,17 @@ struct lockdep_map;
#define MAX_LOCKDEP_SUBCLASSES 8UL
/*
+ * NR_LOCKDEP_CACHING_CLASSES ... Number of classes
+ * cached in the instance of lockdep_map
+ *
+ * Currently main class (subclass == 0) and signle depth subclass
+ * are cached in lockdep_map. This optimization is mainly targeting
+ * on rq->lock. double_rq_lock() acquires this highly competitive with
+ * single depth.
+ */
+#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.)
@@ -40,6 +55,8 @@ struct lock_class_key {
struct lockdep_subclass_key subkeys[MAX_LOCKDEP_SUBCLASSES];
};
+extern struct lock_class_key __lockdep_no_validate__;
+
#define LOCKSTAT_POINTS 4
/*
@@ -132,7 +149,7 @@ void clear_lock_stats(struct lock_class *class);
*/
struct lockdep_map {
struct lock_class_key *key;
- struct lock_class *class_cache;
+ struct lock_class *class_cache[NR_LOCKDEP_CACHING_CLASSES];
const char *name;
#ifdef CONFIG_LOCK_STAT
int cpu;
@@ -149,6 +166,12 @@ struct lock_list {
struct lock_class *class;
struct stack_trace trace;
int distance;
+
+ /*
+ * The parent field is used to implement breadth-first search, and the
+ * bit 0 is reused to indicate if the lock has been accessed in BFS.
+ */
+ struct lock_list *parent;
};
/*
@@ -208,10 +231,12 @@ struct held_lock {
* interrupt context:
*/
unsigned int irq_context:2; /* bit 0 - soft, bit 1 - hard */
- unsigned int trylock:1;
+ unsigned int trylock:1; /* 16 bits */
+
unsigned int read:2; /* see lock_acquire() comment */
unsigned int check:2; /* see lock_acquire() comment */
unsigned int hardirqs_off:1;
+ unsigned int references:11; /* 32 bits */
};
/*
@@ -259,6 +284,19 @@ extern void lockdep_init_map(struct lockdep_map *lock, const char *name,
lockdep_init_map(&(lock)->dep_map, #lock, \
(lock)->dep_map.key, sub)
+#define lockdep_set_novalidate_class(lock) \
+ lockdep_set_class(lock, &__lockdep_no_validate__)
+/*
+ * Compare locking classes
+ */
+#define lockdep_match_class(lock, key) lockdep_match_key(&(lock)->dep_map, key)
+
+static inline int lockdep_match_key(struct lockdep_map *lock,
+ struct lock_class_key *key)
+{
+ return lock->key == key;
+}
+
/*
* Acquire a lock.
*
@@ -281,6 +319,10 @@ extern void lock_acquire(struct lockdep_map *lock, unsigned int subclass,
extern void lock_release(struct lockdep_map *lock, int nested,
unsigned long ip);
+#define lockdep_is_held(lock) lock_is_held(&(lock)->dep_map)
+
+extern int lock_is_held(struct lockdep_map *lock);
+
extern void lock_set_class(struct lockdep_map *lock, const char *name,
struct lock_class_key *key, unsigned int subclass,
unsigned long ip);
@@ -299,6 +341,8 @@ extern void lockdep_trace_alloc(gfp_t mask);
#define lockdep_depth(tsk) (debug_locks ? (tsk)->lockdep_depth : 0)
+#define lockdep_assert_held(l) WARN_ON(debug_locks && !lockdep_is_held(l))
+
#else /* !LOCKDEP */
static inline void lockdep_off(void)
@@ -327,6 +371,14 @@ static inline void lockdep_on(void)
do { (void)(key); } while (0)
#define lockdep_set_subclass(lock, sub) do { } while (0)
+#define lockdep_set_novalidate_class(lock) do { } while (0)
+
+/*
+ * We don't define lockdep_match_class() and lockdep_match_key() for !LOCKDEP
+ * case since the result is not well defined and the caller should rather
+ * #ifdef the call himself.
+ */
+
# define INIT_LOCKDEP
# define lockdep_reset() do { debug_locks = 1; } while (0)
# define lockdep_free_key_range(start, size) do { } while (0)
@@ -338,6 +390,8 @@ struct lock_class_key { };
#define lockdep_depth(tsk) (0)
+#define lockdep_assert_held(l) do { } while (0)
+
#endif /* !LOCKDEP */
#ifdef CONFIG_LOCK_STAT
@@ -381,14 +435,6 @@ do { \
#endif /* CONFIG_LOCKDEP */
-#ifdef CONFIG_GENERIC_HARDIRQS
-extern void early_init_irq_lock_class(void);
-#else
-static inline void early_init_irq_lock_class(void)
-{
-}
-#endif
-
#ifdef CONFIG_TRACE_IRQFLAGS
extern void early_boot_irqs_off(void);
extern void early_boot_irqs_on(void);
@@ -503,4 +549,8 @@ do { \
# define might_lock_read(lock) do { } while (0)
#endif
+#ifdef CONFIG_PROVE_RCU
+extern void lockdep_rcu_dereference(const char *file, const int line);
+#endif
+
#endif /* __LINUX_LOCKDEP_H */