[PATCH] lockdep: prove spinlock rwlock locking correctness

Use the lock validator framework to prove spinlock and rwlock locking
correctness.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

7 files changed, 92 insertions, 23 deletions

diff --git a/include/asm-i386/spinlock.h b/include/asm-i386/spinlock.h
index 7e29b51..87c40f8 100644
--- a/include/asm-i386/spinlock.h
+++ b/include/asm-i386/spinlock.h
@@ -68,6 +68,12 @@ static inline void __raw_spin_lock(raw_spinlock_t *lock)
 		"=m" (lock->slock) : : "memory");
 }
 
+/*
+ * It is easier for the lock validator if interrupts are not re-enabled
+ * in the middle of a lock-acquire. This is a performance feature anyway
+ * so we turn it off:
+ */
+#ifndef CONFIG_PROVE_LOCKING
 static inline void __raw_spin_lock_flags(raw_spinlock_t *lock, unsigned long flags)
 {
 	alternative_smp(
@@ -75,6 +81,7 @@ static inline void __raw_spin_lock_flags(raw_spinlock_t *lock, unsigned long fla
 		__raw_spin_lock_string_up,
 		"=m" (lock->slock) : "r" (flags) : "memory");
 }
+#endif
 
 static inline int __raw_spin_trylock(raw_spinlock_t *lock)
 {
diff --git a/include/linux/spinlock.h b/include/linux/spinlock.h
index ae23bee..31473db 100644
--- a/include/linux/spinlock.h
+++ b/include/linux/spinlock.h
@@ -82,14 +82,40 @@ extern int __lockfunc generic__raw_read_trylock(raw_rwlock_t *lock);
 /*
  * Pull the __raw*() functions/declarations (UP-nondebug doesnt need them):
  */
-#if defined(CONFIG_SMP)
+#ifdef CONFIG_SMP
 # include <asm/spinlock.h>
 #else
 # include <linux/spinlock_up.h>
 #endif
 
-#define spin_lock_init(lock)	do { *(lock) = SPIN_LOCK_UNLOCKED; } while (0)
-#define rwlock_init(lock)	do { *(lock) = RW_LOCK_UNLOCKED; } while (0)
+#ifdef CONFIG_DEBUG_SPINLOCK
+  extern void __spin_lock_init(spinlock_t *lock, const char *name,
+			       struct lock_class_key *key);
+# define spin_lock_init(lock)					\
+do {								\
+	static struct lock_class_key __key;			\
+								\
+	__spin_lock_init((lock), #lock, &__key);		\
+} while (0)
+
+#else
+# define spin_lock_init(lock)					\
+	do { *(lock) = SPIN_LOCK_UNLOCKED; } while (0)
+#endif
+
+#ifdef CONFIG_DEBUG_SPINLOCK
+  extern void __rwlock_init(rwlock_t *lock, const char *name,
+			    struct lock_class_key *key);
+# define rwlock_init(lock)					\
+do {								\
+	static struct lock_class_key __key;			\
+								\
+	__rwlock_init((lock), #lock, &__key);			\
+} while (0)
+#else
+# define rwlock_init(lock)					\
+	do { *(lock) = RW_LOCK_UNLOCKED; } while (0)
+#endif
 
 #define spin_is_locked(lock)	__raw_spin_is_locked(&(lock)->raw_lock)
 
@@ -113,7 +139,6 @@ extern int __lockfunc generic__raw_read_trylock(raw_rwlock_t *lock);
 #define _raw_spin_lock_flags(lock, flags) _raw_spin_lock(lock)
  extern int _raw_spin_trylock(spinlock_t *lock);
  extern void _raw_spin_unlock(spinlock_t *lock);
-
  extern void _raw_read_lock(rwlock_t *lock);
  extern int _raw_read_trylock(rwlock_t *lock);
  extern void _raw_read_unlock(rwlock_t *lock);
@@ -121,17 +146,17 @@ extern int __lockfunc generic__raw_read_trylock(raw_rwlock_t *lock);
  extern int _raw_write_trylock(rwlock_t *lock);
  extern void _raw_write_unlock(rwlock_t *lock);
 #else
-# define _raw_spin_unlock(lock)		__raw_spin_unlock(&(lock)->raw_lock)
-# define _raw_spin_trylock(lock)	__raw_spin_trylock(&(lock)->raw_lock)
 # define _raw_spin_lock(lock)		__raw_spin_lock(&(lock)->raw_lock)
 # define _raw_spin_lock_flags(lock, flags) \
 		__raw_spin_lock_flags(&(lock)->raw_lock, *(flags))
+# define _raw_spin_trylock(lock)	__raw_spin_trylock(&(lock)->raw_lock)
+# define _raw_spin_unlock(lock)		__raw_spin_unlock(&(lock)->raw_lock)
 # define _raw_read_lock(rwlock)		__raw_read_lock(&(rwlock)->raw_lock)
-# define _raw_write_lock(rwlock)	__raw_write_lock(&(rwlock)->raw_lock)
-# define _raw_read_unlock(rwlock)	__raw_read_unlock(&(rwlock)->raw_lock)
-# define _raw_write_unlock(rwlock)	__raw_write_unlock(&(rwlock)->raw_lock)
 # define _raw_read_trylock(rwlock)	__raw_read_trylock(&(rwlock)->raw_lock)
+# define _raw_read_unlock(rwlock)	__raw_read_unlock(&(rwlock)->raw_lock)
+# define _raw_write_lock(rwlock)	__raw_write_lock(&(rwlock)->raw_lock)
 # define _raw_write_trylock(rwlock)	__raw_write_trylock(&(rwlock)->raw_lock)
+# define _raw_write_unlock(rwlock)	__raw_write_unlock(&(rwlock)->raw_lock)
 #endif
 
 #define read_can_lock(rwlock)		__raw_read_can_lock(&(rwlock)->raw_lock)
@@ -147,6 +172,13 @@ extern int __lockfunc generic__raw_read_trylock(raw_rwlock_t *lock);
 #define write_trylock(lock)		__cond_lock(_write_trylock(lock))
 
 #define spin_lock(lock)			_spin_lock(lock)
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define spin_lock_nested(lock, subclass) _spin_lock_nested(lock, subclass)
+#else
+# define spin_lock_nested(lock, subclass) _spin_lock(lock)
+#endif
+
 #define write_lock(lock)		_write_lock(lock)
 #define read_lock(lock)			_read_lock(lock)
 
@@ -172,21 +204,18 @@ extern int __lockfunc generic__raw_read_trylock(raw_rwlock_t *lock);
 /*
  * We inline the unlock functions in the nondebug case:
  */
-#if defined(CONFIG_DEBUG_SPINLOCK) || defined(CONFIG_PREEMPT) || !defined(CONFIG_SMP)
+#if defined(CONFIG_DEBUG_SPINLOCK) || defined(CONFIG_PREEMPT) || \
+	!defined(CONFIG_SMP)
 # define spin_unlock(lock)		_spin_unlock(lock)
 # define read_unlock(lock)		_read_unlock(lock)
 # define write_unlock(lock)		_write_unlock(lock)
-#else
-# define spin_unlock(lock)		__raw_spin_unlock(&(lock)->raw_lock)
-# define read_unlock(lock)		__raw_read_unlock(&(lock)->raw_lock)
-# define write_unlock(lock)		__raw_write_unlock(&(lock)->raw_lock)
-#endif
-
-#if defined(CONFIG_DEBUG_SPINLOCK) || defined(CONFIG_PREEMPT) || !defined(CONFIG_SMP)
 # define spin_unlock_irq(lock)		_spin_unlock_irq(lock)
 # define read_unlock_irq(lock)		_read_unlock_irq(lock)
 # define write_unlock_irq(lock)		_write_unlock_irq(lock)
 #else
+# define spin_unlock(lock)		__raw_spin_unlock(&(lock)->raw_lock)
+# define read_unlock(lock)		__raw_read_unlock(&(lock)->raw_lock)
+# define write_unlock(lock)		__raw_write_unlock(&(lock)->raw_lock)
 # define spin_unlock_irq(lock) \
     do { __raw_spin_unlock(&(lock)->raw_lock); local_irq_enable(); } while (0)
 # define read_unlock_irq(lock) \
diff --git a/include/linux/spinlock_api_smp.h b/include/linux/spinlock_api_smp.h
index 78e6989..b2c4f82 100644
--- a/include/linux/spinlock_api_smp.h
+++ b/include/linux/spinlock_api_smp.h
@@ -20,6 +20,8 @@ int in_lock_functions(unsigned long addr);
 #define assert_spin_locked(x)	BUG_ON(!spin_is_locked(x))
 
 void __lockfunc _spin_lock(spinlock_t *lock)		__acquires(spinlock_t);
+void __lockfunc _spin_lock_nested(spinlock_t *lock, int subclass)
+							__acquires(spinlock_t);
 void __lockfunc _read_lock(rwlock_t *lock)		__acquires(rwlock_t);
 void __lockfunc _write_lock(rwlock_t *lock)		__acquires(rwlock_t);
 void __lockfunc _spin_lock_bh(spinlock_t *lock)		__acquires(spinlock_t);
diff --git a/include/linux/spinlock_api_up.h b/include/linux/spinlock_api_up.h
index cd81cee..67faa04 100644
--- a/include/linux/spinlock_api_up.h
+++ b/include/linux/spinlock_api_up.h
@@ -49,6 +49,7 @@
   do { local_irq_restore(flags); __UNLOCK(lock); } while (0)
 
 #define _spin_lock(lock)			__LOCK(lock)
+#define _spin_lock_nested(lock, subclass)	__LOCK(lock)
 #define _read_lock(lock)			__LOCK(lock)
 #define _write_lock(lock)			__LOCK(lock)
 #define _spin_lock_bh(lock)			__LOCK_BH(lock)
diff --git a/include/linux/spinlock_types.h b/include/linux/spinlock_types.h
index f5d4ed7..dc5fb69 100644
--- a/include/linux/spinlock_types.h
+++ b/include/linux/spinlock_types.h
@@ -9,6 +9,8 @@
  * Released under the General Public License (GPL).
  */
 
+#include <linux/lockdep.h>
+
 #if defined(CONFIG_SMP)
 # include <asm/spinlock_types.h>
 #else
@@ -24,6 +26,9 @@ typedef struct {
 	unsigned int magic, owner_cpu;
 	void *owner;
 #endif
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+	struct lockdep_map dep_map;
+#endif
 } spinlock_t;
 
 #define SPINLOCK_MAGIC		0xdead4ead
@@ -37,28 +42,47 @@ typedef struct {
 	unsigned int magic, owner_cpu;
 	void *owner;
 #endif
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+	struct lockdep_map dep_map;
+#endif
 } rwlock_t;
 
 #define RWLOCK_MAGIC		0xdeaf1eed
 
 #define SPINLOCK_OWNER_INIT	((void *)-1L)
 
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define SPIN_DEP_MAP_INIT(lockname)	.dep_map = { .name = #lockname }
+#else
+# define SPIN_DEP_MAP_INIT(lockname)
+#endif
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+# define RW_DEP_MAP_INIT(lockname)	.dep_map = { .name = #lockname }
+#else
+# define RW_DEP_MAP_INIT(lockname)
+#endif
+
 #ifdef CONFIG_DEBUG_SPINLOCK
 # define __SPIN_LOCK_UNLOCKED(lockname)					\
 	(spinlock_t)	{	.raw_lock = __RAW_SPIN_LOCK_UNLOCKED,	\
 				.magic = SPINLOCK_MAGIC,		\
 				.owner = SPINLOCK_OWNER_INIT,		\
-				.owner_cpu = -1 }
+				.owner_cpu = -1,			\
+				SPIN_DEP_MAP_INIT(lockname) }
 #define __RW_LOCK_UNLOCKED(lockname)					\
 	(rwlock_t)	{	.raw_lock = __RAW_RW_LOCK_UNLOCKED,	\
 				.magic = RWLOCK_MAGIC,			\
 				.owner = SPINLOCK_OWNER_INIT,		\
-				.owner_cpu = -1 }
+				.owner_cpu = -1,			\
+				RW_DEP_MAP_INIT(lockname) }
 #else
 # define __SPIN_LOCK_UNLOCKED(lockname) \
-	(spinlock_t)	{	.raw_lock = __RAW_SPIN_LOCK_UNLOCKED }
+	(spinlock_t)	{	.raw_lock = __RAW_SPIN_LOCK_UNLOCKED,	\
+				SPIN_DEP_MAP_INIT(lockname) }
 #define __RW_LOCK_UNLOCKED(lockname) \
-	(rwlock_t)	{	.raw_lock = __RAW_RW_LOCK_UNLOCKED }
+	(rwlock_t)	{	.raw_lock = __RAW_RW_LOCK_UNLOCKED,	\
+				RW_DEP_MAP_INIT(lockname) }
 #endif
 
 #define SPIN_LOCK_UNLOCKED	__SPIN_LOCK_UNLOCKED(old_style_spin_init)
diff --git a/include/linux/spinlock_types_up.h b/include/linux/spinlock_types_up.h
index 04135b0..27644af 100644
--- a/include/linux/spinlock_types_up.h
+++ b/include/linux/spinlock_types_up.h
@@ -12,10 +12,14 @@
  * Released under the General Public License (GPL).
  */
 
-#ifdef CONFIG_DEBUG_SPINLOCK
+#if defined(CONFIG_DEBUG_SPINLOCK) || \
+	defined(CONFIG_DEBUG_LOCK_ALLOC)
 
 typedef struct {
 	volatile unsigned int slock;
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+	struct lockdep_map dep_map;
+#endif
 } raw_spinlock_t;
 
 #define __RAW_SPIN_LOCK_UNLOCKED { 1 }
@@ -30,6 +34,9 @@ typedef struct { } raw_spinlock_t;
 
 typedef struct {
 	/* no debug version on UP */
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+	struct lockdep_map dep_map;
+#endif
 } raw_rwlock_t;
 
 #define __RAW_RW_LOCK_UNLOCKED { }
diff --git a/include/linux/spinlock_up.h b/include/linux/spinlock_up.h
index 31accf2..ea54c4c 100644
--- a/include/linux/spinlock_up.h
+++ b/include/linux/spinlock_up.h
@@ -18,7 +18,6 @@
  */
 
 #ifdef CONFIG_DEBUG_SPINLOCK
-
 #define __raw_spin_is_locked(x)		((x)->slock == 0)
 
 static inline void __raw_spin_lock(raw_spinlock_t *lock)