1 files changed, 213 insertions, 222 deletions

diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h
index 664f52c6dd4c..1f1099dac3f0 100644
--- a/include/linux/lockdep.h
+++ b/include/linux/lockdep.h
@@ -10,16 +10,11 @@
 #ifndef __LINUX_LOCKDEP_H
 #define __LINUX_LOCKDEP_H
 
-struct task_struct;
-struct lockdep_map;
-
-/* for sysctl */
-extern int prove_locking;
-extern int lock_stat;
-
-#define MAX_LOCKDEP_SUBCLASSES		8UL
+#include <linux/lockdep_types.h>
+#include <linux/smp.h>
+#include <asm/percpu.h>
 
-#include <linux/types.h>
+struct task_struct;
 
 #ifdef CONFIG_LOCKDEP
 
@@ -28,142 +23,6 @@ extern int lock_stat;
 #include <linux/debug_locks.h>
 #include <linux/stacktrace.h>
 
-/*
- * We'd rather not expose kernel/lockdep_states.h this wide, but we do need
- * the total number of states... :-(
- */
-#define XXX_LOCK_USAGE_STATES		(1+2*4)
-
-/*
- * 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
-
-/*
- * 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 {
-	union {
-		struct hlist_node		hash_entry;
-		struct lockdep_subclass_key	subkeys[MAX_LOCKDEP_SUBCLASSES];
-	};
-};
-
-extern struct lock_class_key __lockdep_no_validate__;
-
-struct lock_trace;
-
-#define LOCKSTAT_POINTS		4
-
-/*
- * The lock-class itself. The order of the structure members matters.
- * reinit_class() zeroes the key member and all subsequent members.
- */
-struct lock_class {
-	/*
-	 * class-hash:
-	 */
-	struct hlist_node		hash_entry;
-
-	/*
-	 * 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;
-
-	const struct lockdep_subclass_key *key;
-	unsigned int			subclass;
-	unsigned int			dep_gen_id;
-
-	/*
-	 * IRQ/softirq usage tracking bits:
-	 */
-	unsigned long			usage_mask;
-	const struct lock_trace		*usage_traces[XXX_LOCK_USAGE_STATES];
-
-	/*
-	 * Generation counter, when doing certain classes of graph walking,
-	 * to ensure that we check one node only once:
-	 */
-	int				name_version;
-	const char			*name;
-
-#ifdef CONFIG_LOCK_STAT
-	unsigned long			contention_point[LOCKSTAT_POINTS];
-	unsigned long			contending_point[LOCKSTAT_POINTS];
-#endif
-} __no_randomize_layout;
-
-#ifdef CONFIG_LOCK_STAT
-struct lock_time {
-	s64				min;
-	s64				max;
-	s64				total;
-	unsigned long			nr;
-};
-
-enum bounce_type {
-	bounce_acquired_write,
-	bounce_acquired_read,
-	bounce_contended_write,
-	bounce_contended_read,
-	nr_bounce_types,
-
-	bounce_acquired = bounce_acquired_write,
-	bounce_contended = bounce_contended_write,
-};
-
-struct lock_class_stats {
-	unsigned long			contention_point[LOCKSTAT_POINTS];
-	unsigned long			contending_point[LOCKSTAT_POINTS];
-	struct lock_time		read_waittime;
-	struct lock_time		write_waittime;
-	struct lock_time		read_holdtime;
-	struct lock_time		write_holdtime;
-	unsigned long			bounces[nr_bounce_types];
-};
-
-struct lock_class_stats lock_stats(struct lock_class *class);
-void clear_lock_stats(struct lock_class *class);
-#endif
-
-/*
- * Map the lock object (the lock instance) to the lock-class object.
- * This is embedded into specific lock instances:
- */
-struct lockdep_map {
-	struct lock_class_key		*key;
-	struct lock_class		*class_cache[NR_LOCKDEP_CACHING_CLASSES];
-	const char			*name;
-#ifdef CONFIG_LOCK_STAT
-	int				cpu;
-	unsigned long			ip;
-#endif
-};
-
 static inline void lockdep_copy_map(struct lockdep_map *to,
 				    struct lockdep_map *from)
 {
@@ -191,7 +50,11 @@ struct lock_list {
 	struct lock_class		*class;
 	struct lock_class		*links_to;
 	const struct lock_trace		*trace;
-	int				distance;
+	u16				distance;
+	/* bitmap of different dependencies from head to this */
+	u8				dep;
+	/* used by BFS to record whether "prev -> this" only has -(*R)-> */
+	u8				only_xr;
 
 	/*
 	 * The parent field is used to implement breadth-first search, and the
@@ -287,8 +150,27 @@ extern void lockdep_set_selftest_task(struct task_struct *task);
 
 extern void lockdep_init_task(struct task_struct *task);
 
-extern void lockdep_off(void);
-extern void lockdep_on(void);
+/*
+ * Split the recursion counter in two to readily detect 'off' vs recursion.
+ */
+#define LOCKDEP_RECURSION_BITS	16
+#define LOCKDEP_OFF		(1U << LOCKDEP_RECURSION_BITS)
+#define LOCKDEP_RECURSION_MASK	(LOCKDEP_OFF - 1)
+
+/*
+ * lockdep_{off,on}() are macros to avoid tracing and kprobes; not inlines due
+ * to header dependencies.
+ */
+
+#define lockdep_off()					\
+do {							\
+	current->lockdep_recursion += LOCKDEP_OFF;	\
+} while (0)
+
+#define lockdep_on()					\
+do {							\
+	current->lockdep_recursion -= LOCKDEP_OFF;	\
+} while (0)
 
 extern void lockdep_register_key(struct lock_class_key *key);
 extern void lockdep_unregister_key(struct lock_class_key *key);
@@ -299,8 +181,28 @@ extern void lockdep_unregister_key(struct lock_class_key *key);
  * to lockdep:
  */
 
-extern void lockdep_init_map(struct lockdep_map *lock, const char *name,
-			     struct lock_class_key *key, int subclass);
+extern void lockdep_init_map_type(struct lockdep_map *lock, const char *name,
+	struct lock_class_key *key, int subclass, u8 inner, u8 outer, u8 lock_type);
+
+static inline void
+lockdep_init_map_waits(struct lockdep_map *lock, const char *name,
+		       struct lock_class_key *key, int subclass, u8 inner, u8 outer)
+{
+	lockdep_init_map_type(lock, name, key, subclass, inner, outer, LD_LOCK_NORMAL);
+}
+
+static inline void
+lockdep_init_map_wait(struct lockdep_map *lock, const char *name,
+		      struct lock_class_key *key, int subclass, u8 inner)
+{
+	lockdep_init_map_waits(lock, name, key, subclass, inner, LD_WAIT_INV);
+}
+
+static inline void lockdep_init_map(struct lockdep_map *lock, const char *name,
+			     struct lock_class_key *key, int subclass)
+{
+	lockdep_init_map_wait(lock, name, key, subclass, LD_WAIT_INV);
+}
 
 /*
  * Reinitialize a lock key - for cases where there is special locking or
@@ -308,18 +210,33 @@ extern void lockdep_init_map(struct lockdep_map *lock, const char *name,
  * of dependencies wrong: they are either too broad (they need a class-split)
  * or they are too narrow (they suffer from a false class-split):
  */
-#define lockdep_set_class(lock, key) \
-		lockdep_init_map(&(lock)->dep_map, #key, key, 0)
-#define lockdep_set_class_and_name(lock, key, name) \
-		lockdep_init_map(&(lock)->dep_map, name, key, 0)
-#define lockdep_set_class_and_subclass(lock, key, sub) \
-		lockdep_init_map(&(lock)->dep_map, #key, key, sub)
-#define lockdep_set_subclass(lock, sub)	\
-		lockdep_init_map(&(lock)->dep_map, #lock, \
-				 (lock)->dep_map.key, sub)
+#define lockdep_set_class(lock, key)				\
+	lockdep_init_map_type(&(lock)->dep_map, #key, key, 0,	\
+			      (lock)->dep_map.wait_type_inner,	\
+			      (lock)->dep_map.wait_type_outer,	\
+			      (lock)->dep_map.lock_type)
+
+#define lockdep_set_class_and_name(lock, key, name)		\
+	lockdep_init_map_type(&(lock)->dep_map, name, key, 0,	\
+			      (lock)->dep_map.wait_type_inner,	\
+			      (lock)->dep_map.wait_type_outer,	\
+			      (lock)->dep_map.lock_type)
+
+#define lockdep_set_class_and_subclass(lock, key, sub)		\
+	lockdep_init_map_type(&(lock)->dep_map, #key, key, sub,	\
+			      (lock)->dep_map.wait_type_inner,	\
+			      (lock)->dep_map.wait_type_outer,	\
+			      (lock)->dep_map.lock_type)
+
+#define lockdep_set_subclass(lock, sub)					\
+	lockdep_init_map_type(&(lock)->dep_map, #lock, (lock)->dep_map.key, sub,\
+			      (lock)->dep_map.wait_type_inner,		\
+			      (lock)->dep_map.wait_type_outer,		\
+			      (lock)->dep_map.lock_type)
 
 #define lockdep_set_novalidate_class(lock) \
 	lockdep_set_class_and_name(lock, &__lockdep_no_validate__, #lock)
+
 /*
  * Compare locking classes
  */
@@ -351,6 +268,11 @@ extern void lock_acquire(struct lockdep_map *lock, unsigned int subclass,
 
 extern void lock_release(struct lockdep_map *lock, unsigned long ip);
 
+/* lock_is_held_type() returns */
+#define LOCK_STATE_UNKNOWN	-1
+#define LOCK_STATE_NOT_HELD	0
+#define LOCK_STATE_HELD		1
+
 /*
  * Same "read" as for lock_acquire(), except -1 means any.
  */
@@ -368,6 +290,9 @@ extern void lock_set_class(struct lockdep_map *lock, const char *name,
 			   struct lock_class_key *key, unsigned int subclass,
 			   unsigned long ip);
 
+#define lock_set_novalidate_class(l, n, i) \
+	lock_set_class(l, n, &__lockdep_no_validate__, 0, i)
+
 static inline void lock_set_subclass(struct lockdep_map *lock,
 		unsigned int subclass, unsigned long ip)
 {
@@ -376,8 +301,6 @@ static inline void lock_set_subclass(struct lockdep_map *lock,
 
 extern void lock_downgrade(struct lockdep_map *lock, unsigned long ip);
 
-struct pin_cookie { unsigned int val; };
-
 #define NIL_COOKIE (struct pin_cookie){ .val = 0U, }
 
 extern struct pin_cookie lock_pin_lock(struct lockdep_map *lock);
@@ -386,21 +309,29 @@ extern void lock_unpin_lock(struct lockdep_map *lock, struct pin_cookie);
 
 #define lockdep_depth(tsk)	(debug_locks ? (tsk)->lockdep_depth : 0)
 
-#define lockdep_assert_held(l)	do {				\
-		WARN_ON(debug_locks && !lockdep_is_held(l));	\
-	} while (0)
+#define lockdep_assert(cond)		\
+	do { WARN_ON(debug_locks && !(cond)); } while (0)
+
+#define lockdep_assert_once(cond)	\
+	do { WARN_ON_ONCE(debug_locks && !(cond)); } while (0)
+
+#define lockdep_assert_held(l)		\
+	lockdep_assert(lockdep_is_held(l) != LOCK_STATE_NOT_HELD)
+
+#define lockdep_assert_not_held(l)	\
+	lockdep_assert(lockdep_is_held(l) != LOCK_STATE_HELD)
 
-#define lockdep_assert_held_write(l)	do {			\
-		WARN_ON(debug_locks && !lockdep_is_held_type(l, 0));	\
-	} while (0)
+#define lockdep_assert_held_write(l)	\
+	lockdep_assert(lockdep_is_held_type(l, 0))
 
-#define lockdep_assert_held_read(l)	do {				\
-		WARN_ON(debug_locks && !lockdep_is_held_type(l, 1));	\
-	} while (0)
+#define lockdep_assert_held_read(l)	\
+	lockdep_assert(lockdep_is_held_type(l, 1))
 
-#define lockdep_assert_held_once(l)	do {				\
-		WARN_ON_ONCE(debug_locks && !lockdep_is_held(l));	\
-	} while (0)
+#define lockdep_assert_held_once(l)		\
+	lockdep_assert_once(lockdep_is_held(l) != LOCK_STATE_NOT_HELD)
+
+#define lockdep_assert_none_held_once()		\
+	lockdep_assert_once(!current->lockdep_depth)
 
 #define lockdep_recursing(tsk)	((tsk)->lockdep_recursion)
 
@@ -429,9 +360,16 @@ 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, i)			do { } while (0)
 # define lock_downgrade(l, i)			do { } while (0)
-# define lock_set_class(l, n, k, s, i)		do { } while (0)
+# define lock_set_class(l, n, key, s, i)	do { (void)(key); } while (0)
+# define lock_set_novalidate_class(l, n, i)	do { } while (0)
 # define lock_set_subclass(l, s, i)		do { } while (0)
 # define lockdep_init()				do { } while (0)
+# define lockdep_init_map_type(lock, name, key, sub, inner, outer, type) \
+		do { (void)(name); (void)(key); } while (0)
+# define lockdep_init_map_waits(lock, name, key, sub, inner, outer) \
+		do { (void)(name); (void)(key); } while (0)
+# define lockdep_init_map_wait(lock, name, key, sub, inner) \
+		do { (void)(name); (void)(key); } while (0)
 # define lockdep_init_map(lock, name, key, sub) \
 		do { (void)(name); (void)(key); } while (0)
 # define lockdep_set_class(lock, key)		do { (void)(key); } while (0)
@@ -452,10 +390,6 @@ static inline void lockdep_set_selftest_task(struct task_struct *task)
 # define lockdep_reset()		do { debug_locks = 1; } while (0)
 # define lockdep_free_key_range(start, size)	do { } while (0)
 # define lockdep_sys_exit() 			do { } while (0)
-/*
- * The class key takes no space if lockdep is disabled:
- */
-struct lock_class_key { };
 
 static inline void lockdep_register_key(struct lock_class_key *key)
 {
@@ -465,24 +399,28 @@ static inline void lockdep_unregister_key(struct lock_class_key *key)
 {
 }
 
-/*
- * The lockdep_map takes no space if lockdep is disabled:
- */
-struct lockdep_map { };
-
 #define lockdep_depth(tsk)	(0)
 
+/*
+ * Dummy forward declarations, allow users to write less ifdef-y code
+ * and depend on dead code elimination.
+ */
+extern int lock_is_held(const void *);
+extern int lockdep_is_held(const void *);
 #define lockdep_is_held_type(l, r)		(1)
 
+#define lockdep_assert(c)			do { } while (0)
+#define lockdep_assert_once(c)			do { } while (0)
+
 #define lockdep_assert_held(l)			do { (void)(l); } while (0)
-#define lockdep_assert_held_write(l)	do { (void)(l); } while (0)
+#define lockdep_assert_not_held(l)		do { (void)(l); } while (0)
+#define lockdep_assert_held_write(l)		do { (void)(l); } while (0)
 #define lockdep_assert_held_read(l)		do { (void)(l); } while (0)
 #define lockdep_assert_held_once(l)		do { (void)(l); } while (0)
+#define lockdep_assert_none_held_once()	do { } while (0)
 
 #define lockdep_recursing(tsk)			(0)
 
-struct pin_cookie { };
-
 #define NIL_COOKIE (struct pin_cookie){ }
 
 #define lockdep_pin_lock(l)			({ struct pin_cookie cookie = { }; cookie; })
@@ -547,23 +485,6 @@ do {								\
 
 #endif /* CONFIG_LOCK_STAT */
 
-#ifdef CONFIG_LOCKDEP
-
-/*
- * On lockdep we dont want the hand-coded irq-enable of
- * _raw_*_lock_flags() code, because lockdep assumes
- * that interrupts are not re-enabled during lock-acquire:
- */
-#define LOCK_CONTENDED_FLAGS(_lock, try, lock, lockfl, flags) \
-	LOCK_CONTENDED((_lock), (try), (lock))
-
-#else /* CONFIG_LOCKDEP */
-
-#define LOCK_CONTENDED_FLAGS(_lock, try, lock, lockfl, flags) \
-	lockfl((_lock), (flags))
-
-#endif /* CONFIG_LOCKDEP */
-
 #ifdef CONFIG_PROVE_LOCKING
 extern void print_irqtrace_events(struct task_struct *curr);
 #else
@@ -572,6 +493,20 @@ static inline void print_irqtrace_events(struct task_struct *curr)
 }
 #endif
 
+/* Variable used to make lockdep treat read_lock() as recursive in selftests */
+#ifdef CONFIG_DEBUG_LOCKING_API_SELFTESTS
+extern unsigned int force_read_lock_recursive;
+#else /* CONFIG_DEBUG_LOCKING_API_SELFTESTS */
+#define force_read_lock_recursive 0
+#endif /* CONFIG_DEBUG_LOCKING_API_SELFTESTS */
+
+#ifdef CONFIG_LOCKDEP
+extern bool read_lock_is_recursive(void);
+#else /* CONFIG_LOCKDEP */
+/* If !LOCKDEP, the value is meaningless */
+#define read_lock_is_recursive() 0
+#endif
+
 /*
  * For trivial one-depth nesting of a lock-class, the following
  * global define can be used. (Subsystems with multiple levels
@@ -593,7 +528,14 @@ static inline void print_irqtrace_events(struct task_struct *curr)
 #define spin_release(l, i)			lock_release(l, i)
 
 #define rwlock_acquire(l, s, t, i)		lock_acquire_exclusive(l, s, t, NULL, i)
-#define rwlock_acquire_read(l, s, t, i)		lock_acquire_shared_recursive(l, s, t, NULL, i)
+#define rwlock_acquire_read(l, s, t, i)					\
+do {									\
+	if (read_lock_is_recursive())					\
+		lock_acquire_shared_recursive(l, s, t, NULL, i);	\
+	else								\
+		lock_acquire_shared(l, s, t, NULL, i);			\
+} while (0)
+
 #define rwlock_release(l, i)			lock_release(l, i)
 
 #define seqcount_acquire(l, s, t, i)		lock_acquire_exclusive(l, s, t, NULL, i)
@@ -615,19 +557,19 @@ static inline void print_irqtrace_events(struct task_struct *curr)
 #define lock_map_release(l)			lock_release(l, _THIS_IP_)
 
 #ifdef CONFIG_PROVE_LOCKING
-# define might_lock(lock) 						\
+# define might_lock(lock)						\
 do {									\
 	typecheck(struct lockdep_map *, &(lock)->dep_map);		\
 	lock_acquire(&(lock)->dep_map, 0, 0, 0, 1, NULL, _THIS_IP_);	\
 	lock_release(&(lock)->dep_map, _THIS_IP_);			\
 } while (0)
-# define might_lock_read(lock) 						\
+# define might_lock_read(lock)						\
 do {									\
 	typecheck(struct lockdep_map *, &(lock)->dep_map);		\
 	lock_acquire(&(lock)->dep_map, 0, 0, 1, 1, NULL, _THIS_IP_);	\
 	lock_release(&(lock)->dep_map, _THIS_IP_);			\
 } while (0)
-# define might_lock_nested(lock, subclass) 				\
+# define might_lock_nested(lock, subclass)				\
 do {									\
 	typecheck(struct lockdep_map *, &(lock)->dep_map);		\
 	lock_acquire(&(lock)->dep_map, subclass, 0, 1, 1, NULL,		\
@@ -635,31 +577,80 @@ do {									\
 	lock_release(&(lock)->dep_map, _THIS_IP_);			\
 } while (0)
 
-#define lockdep_assert_irqs_enabled()	do {				\
-		WARN_ONCE(debug_locks && !current->lockdep_recursion &&	\
-			  !current->hardirqs_enabled,			\
-			  "IRQs not enabled as expected\n");		\
-	} while (0)
+DECLARE_PER_CPU(int, hardirqs_enabled);
+DECLARE_PER_CPU(int, hardirq_context);
+DECLARE_PER_CPU(unsigned int, lockdep_recursion);
 
-#define lockdep_assert_irqs_disabled()	do {				\
-		WARN_ONCE(debug_locks && !current->lockdep_recursion &&	\
-			  current->hardirqs_enabled,			\
-			  "IRQs not disabled as expected\n");		\
-	} while (0)
+#define __lockdep_enabled	(debug_locks && !this_cpu_read(lockdep_recursion))
 
-#define lockdep_assert_in_irq() do {					\
-		WARN_ONCE(debug_locks && !current->lockdep_recursion &&	\
-			  !current->hardirq_context,			\
-			  "Not in hardirq as expected\n");		\
-	} while (0)
+#define lockdep_assert_irqs_enabled()					\
+do {									\
+	WARN_ON_ONCE(__lockdep_enabled && !this_cpu_read(hardirqs_enabled)); \
+} while (0)
+
+#define lockdep_assert_irqs_disabled()					\
+do {									\
+	WARN_ON_ONCE(__lockdep_enabled && this_cpu_read(hardirqs_enabled)); \
+} while (0)
+
+#define lockdep_assert_in_irq()						\
+do {									\
+	WARN_ON_ONCE(__lockdep_enabled && !this_cpu_read(hardirq_context)); \
+} while (0)
+
+#define lockdep_assert_preemption_enabled()				\
+do {									\
+	WARN_ON_ONCE(IS_ENABLED(CONFIG_PREEMPT_COUNT)	&&		\
+		     __lockdep_enabled			&&		\
+		     (preempt_count() != 0		||		\
+		      !this_cpu_read(hardirqs_enabled)));		\
+} while (0)
+
+#define lockdep_assert_preemption_disabled()				\
+do {									\
+	WARN_ON_ONCE(IS_ENABLED(CONFIG_PREEMPT_COUNT)	&&		\
+		     __lockdep_enabled			&&		\
+		     (preempt_count() == 0		&&		\
+		      this_cpu_read(hardirqs_enabled)));		\
+} while (0)
+
+/*
+ * Acceptable for protecting per-CPU resources accessed from BH.
+ * Much like in_softirq() - semantics are ambiguous, use carefully.
+ */
+#define lockdep_assert_in_softirq()					\
+do {									\
+	WARN_ON_ONCE(__lockdep_enabled			&&		\
+		     (!in_softirq() || in_irq() || in_nmi()));		\
+} while (0)
 
 #else
 # define might_lock(lock) do { } while (0)
 # define might_lock_read(lock) do { } while (0)
 # define might_lock_nested(lock, subclass) do { } while (0)
+
 # define lockdep_assert_irqs_enabled() do { } while (0)
 # define lockdep_assert_irqs_disabled() do { } while (0)
 # define lockdep_assert_in_irq() do { } while (0)
+
+# define lockdep_assert_preemption_enabled() do { } while (0)
+# define lockdep_assert_preemption_disabled() do { } while (0)
+# define lockdep_assert_in_softirq() do { } while (0)
+#endif
+
+#ifdef CONFIG_PROVE_RAW_LOCK_NESTING
+
+# define lockdep_assert_RT_in_threaded_ctx() do {			\
+		WARN_ONCE(debug_locks && !current->lockdep_recursion &&	\
+			  lockdep_hardirq_context() &&			\
+			  !(current->hardirq_threaded || current->irq_config),	\
+			  "Not in threaded context on PREEMPT_RT as expected\n");	\
+} while (0)
+
+#else
+
+# define lockdep_assert_RT_in_threaded_ctx() do { } while (0)
+
 #endif
 
 #ifdef CONFIG_LOCKDEP