include/linux/spinlock.h - pub/scm/linux/kernel/git/tglx/history - Git at Google

 #ifndef __LINUX_SPINLOCK_H
 #define __LINUX_SPINLOCK_H

 /*
  * include/linux/spinlock.h - generic locking declarations
  */

 #include <linux/config.h>
 #include <linux/preempt.h>
 #include <linux/linkage.h>
 #include <linux/compiler.h>
 #include <linux/thread_info.h>
 #include <linux/kernel.h>
 #include <linux/stringify.h>

 #include <asm/processor.h>	/* for cpu relax */
 #include <asm/system.h>

 /*
  * Must define these before including other files, inline functions need them
  */
 #define LOCK_SECTION_NAME                       \
         ".text.lock." __stringify(KBUILD_BASENAME)

 #define LOCK_SECTION_START(extra)               \
         ".subsection 1\n\t"                     \
         extra                                   \
         ".ifndef " LOCK_SECTION_NAME "\n\t"     \
         LOCK_SECTION_NAME ":\n\t"               \
         ".endif\n"

 #define LOCK_SECTION_END                        \
         ".previous\n\t"

 #define __lockfunc fastcall __attribute__((section(".spinlock.text")))

 /*
  * If CONFIG_SMP is set, pull in the _raw_* definitions
  */
 #ifdef CONFIG_SMP

 #define assert_spin_locked(x)	BUG_ON(!spin_is_locked(x))
 #include <asm/spinlock.h>

 int __lockfunc _spin_trylock(spinlock_t *lock);
 int __lockfunc _read_trylock(rwlock_t *lock);
 int __lockfunc _write_trylock(rwlock_t *lock);

 void __lockfunc _spin_lock(spinlock_t *lock)	__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_unlock(spinlock_t *lock)	__releases(spinlock_t);
 void __lockfunc _read_unlock(rwlock_t *lock)	__releases(rwlock_t);
 void __lockfunc _write_unlock(rwlock_t *lock)	__releases(rwlock_t);

 unsigned long __lockfunc _spin_lock_irqsave(spinlock_t *lock)	__acquires(spinlock_t);
 unsigned long __lockfunc _read_lock_irqsave(rwlock_t *lock)	__acquires(rwlock_t);
 unsigned long __lockfunc _write_lock_irqsave(rwlock_t *lock)	__acquires(rwlock_t);

 void __lockfunc _spin_lock_irq(spinlock_t *lock)	__acquires(spinlock_t);
 void __lockfunc _spin_lock_bh(spinlock_t *lock)		__acquires(spinlock_t);
 void __lockfunc _read_lock_irq(rwlock_t *lock)		__acquires(rwlock_t);
 void __lockfunc _read_lock_bh(rwlock_t *lock)		__acquires(rwlock_t);
 void __lockfunc _write_lock_irq(rwlock_t *lock)		__acquires(rwlock_t);
 void __lockfunc _write_lock_bh(rwlock_t *lock)		__acquires(rwlock_t);

 void __lockfunc _spin_unlock_irqrestore(spinlock_t *lock, unsigned long flags)	__releases(spinlock_t);
 void __lockfunc _spin_unlock_irq(spinlock_t *lock)				__releases(spinlock_t);
 void __lockfunc _spin_unlock_bh(spinlock_t *lock)				__releases(spinlock_t);
 void __lockfunc _read_unlock_irqrestore(rwlock_t *lock, unsigned long flags)	__releases(rwlock_t);
 void __lockfunc _read_unlock_irq(rwlock_t *lock)				__releases(rwlock_t);
 void __lockfunc _read_unlock_bh(rwlock_t *lock)					__releases(rwlock_t);
 void __lockfunc _write_unlock_irqrestore(rwlock_t *lock, unsigned long flags)	__releases(rwlock_t);
 void __lockfunc _write_unlock_irq(rwlock_t *lock)				__releases(rwlock_t);
 void __lockfunc _write_unlock_bh(rwlock_t *lock)				__releases(rwlock_t);

 int __lockfunc _spin_trylock_bh(spinlock_t *lock);
 int __lockfunc generic_raw_read_trylock(rwlock_t *lock);
 int in_lock_functions(unsigned long addr);

 #else

 #define in_lock_functions(ADDR) 0

 #if !defined(CONFIG_PREEMPT) && !defined(CONFIG_DEBUG_SPINLOCK)
 # define _atomic_dec_and_lock(atomic,lock) atomic_dec_and_test(atomic)
 # define ATOMIC_DEC_AND_LOCK
 #endif

 #ifdef CONFIG_DEBUG_SPINLOCK

 #define SPINLOCK_MAGIC	0x1D244B3C
 typedef struct {
 	unsigned long magic;
 	volatile unsigned long lock;
 	volatile unsigned int babble;
 	const char *module;
 	char *owner;
 	int oline;
 } spinlock_t;
 #define SPIN_LOCK_UNLOCKED (spinlock_t) { SPINLOCK_MAGIC, 0, 10, __FILE__ , NULL, 0}

 #define spin_lock_init(x) \
 	do { \
 		(x)->magic = SPINLOCK_MAGIC; \
 		(x)->lock = 0; \
 		(x)->babble = 5; \
 		(x)->module = __FILE__; \
 		(x)->owner = NULL; \
 		(x)->oline = 0; \
 	} while (0)

 #define CHECK_LOCK(x) \
 	do { \
 	 	if ((x)->magic != SPINLOCK_MAGIC) { \
 			printk(KERN_ERR "%s:%d: spin_is_locked on uninitialized spinlock %p.\n", \
 					__FILE__, __LINE__, (x)); \
 		} \
 	} while(0)

 #define _raw_spin_lock(x)		\
 	do { \
 	 	CHECK_LOCK(x); \
 		if ((x)->lock&&(x)->babble) { \
 			(x)->babble--; \
 			printk("%s:%d: spin_lock(%s:%p) already locked by %s/%d\n", \
 					__FILE__,__LINE__, (x)->module, \
 					(x), (x)->owner, (x)->oline); \
 		} \
 		(x)->lock = 1; \
 		(x)->owner = __FILE__; \
 		(x)->oline = __LINE__; \
 	} while (0)

 /* without debugging, spin_is_locked on UP always says
  * FALSE. --> printk if already locked. */
 #define spin_is_locked(x) \
 	({ \
 	 	CHECK_LOCK(x); \
 		if ((x)->lock&&(x)->babble) { \
 			(x)->babble--; \
 			printk("%s:%d: spin_is_locked(%s:%p) already locked by %s/%d\n", \
 					__FILE__,__LINE__, (x)->module, \
 					(x), (x)->owner, (x)->oline); \
 		} \
 		0; \
 	})

 /* with debugging, assert_spin_locked() on UP does check
  * the lock value properly */
 #define assert_spin_locked(x) \
 	({ \
 		CHECK_LOCK(x); \
 		BUG_ON(!(x)->lock); \
 	})

 /* without debugging, spin_trylock on UP always says
  * TRUE. --> printk if already locked. */
 #define _raw_spin_trylock(x) \
 	({ \
 	 	CHECK_LOCK(x); \
 		if ((x)->lock&&(x)->babble) { \
 			(x)->babble--; \
 			printk("%s:%d: spin_trylock(%s:%p) already locked by %s/%d\n", \
 					__FILE__,__LINE__, (x)->module, \
 					(x), (x)->owner, (x)->oline); \
 		} \
 		(x)->lock = 1; \
 		(x)->owner = __FILE__; \
 		(x)->oline = __LINE__; \
 		1; \
 	})

 #define spin_unlock_wait(x)	\
 	do { \
 	 	CHECK_LOCK(x); \
 		if ((x)->lock&&(x)->babble) { \
 			(x)->babble--; \
 			printk("%s:%d: spin_unlock_wait(%s:%p) owned by %s/%d\n", \
 					__FILE__,__LINE__, (x)->module, (x), \
 					(x)->owner, (x)->oline); \
 		}\
 	} while (0)

 #define _raw_spin_unlock(x) \
 	do { \
 	 	CHECK_LOCK(x); \
 		if (!(x)->lock&&(x)->babble) { \
 			(x)->babble--; \
 			printk("%s:%d: spin_unlock(%s:%p) not locked\n", \
 					__FILE__,__LINE__, (x)->module, (x));\
 		} \
 		(x)->lock = 0; \
 	} while (0)
 #else
 /*
  * gcc versions before ~2.95 have a nasty bug with empty initializers.
  */
 #if (__GNUC__ > 2)
   typedef struct { } spinlock_t;
   #define SPIN_LOCK_UNLOCKED (spinlock_t) { }
 #else
   typedef struct { int gcc_is_buggy; } spinlock_t;
   #define SPIN_LOCK_UNLOCKED (spinlock_t) { 0 }
 #endif

 /*
  * If CONFIG_SMP is unset, declare the _raw_* definitions as nops
  */
 #define spin_lock_init(lock)	do { (void)(lock); } while(0)
 #define _raw_spin_lock(lock)	do { (void)(lock); } while(0)
 #define spin_is_locked(lock)	((void)(lock), 0)
 #define assert_spin_locked(lock)	do { (void)(lock); } while(0)
 #define _raw_spin_trylock(lock)	(((void)(lock), 1))
 #define spin_unlock_wait(lock)	(void)(lock)
 #define _raw_spin_unlock(lock) do { (void)(lock); } while(0)
 #endif /* CONFIG_DEBUG_SPINLOCK */

 /* RW spinlocks: No debug version */

 #if (__GNUC__ > 2)
   typedef struct { } rwlock_t;
   #define RW_LOCK_UNLOCKED (rwlock_t) { }
 #else
   typedef struct { int gcc_is_buggy; } rwlock_t;
   #define RW_LOCK_UNLOCKED (rwlock_t) { 0 }
 #endif

 #define rwlock_init(lock)	do { (void)(lock); } while(0)
 #define _raw_read_lock(lock)	do { (void)(lock); } while(0)
 #define _raw_read_unlock(lock)	do { (void)(lock); } while(0)
 #define _raw_write_lock(lock)	do { (void)(lock); } while(0)
 #define _raw_write_unlock(lock)	do { (void)(lock); } while(0)
 #define read_can_lock(lock)	(((void)(lock), 1))
 #define write_can_lock(lock)	(((void)(lock), 1))
 #define _raw_read_trylock(lock) ({ (void)(lock); (1); })
 #define _raw_write_trylock(lock) ({ (void)(lock); (1); })

 #define _spin_trylock(lock)	({preempt_disable(); _raw_spin_trylock(lock) ? \
 				1 : ({preempt_enable(); 0;});})

 #define _read_trylock(lock)	({preempt_disable();_raw_read_trylock(lock) ? \
 				1 : ({preempt_enable(); 0;});})

 #define _write_trylock(lock)	({preempt_disable(); _raw_write_trylock(lock) ? \
 				1 : ({preempt_enable(); 0;});})

 #define _spin_trylock_bh(lock)	({preempt_disable(); local_bh_disable(); \
 				_raw_spin_trylock(lock) ? \
 				1 : ({preempt_enable(); local_bh_enable(); 0;});})

 #define _spin_lock(lock)	\
 do { \
 	preempt_disable(); \
 	_raw_spin_lock(lock); \
 	__acquire(lock); \
 } while(0)

 #define _write_lock(lock) \
 do { \
 	preempt_disable(); \
 	_raw_write_lock(lock); \
 	__acquire(lock); \
 } while(0)

 #define _read_lock(lock)	\
 do { \
 	preempt_disable(); \
 	_raw_read_lock(lock); \
 	__acquire(lock); \
 } while(0)

 #define _spin_unlock(lock) \
 do { \
 	_raw_spin_unlock(lock); \
 	preempt_enable(); \
 	__release(lock); \
 } while (0)

 #define _write_unlock(lock) \
 do { \
 	_raw_write_unlock(lock); \
 	preempt_enable(); \
 	__release(lock); \
 } while(0)

 #define _read_unlock(lock) \
 do { \
 	_raw_read_unlock(lock); \
 	preempt_enable(); \
 	__release(lock); \
 } while(0)

 #define _spin_lock_irqsave(lock, flags) \
 do {	\
 	local_irq_save(flags); \
 	preempt_disable(); \
 	_raw_spin_lock(lock); \
 	__acquire(lock); \
 } while (0)

 #define _spin_lock_irq(lock) \
 do { \
 	local_irq_disable(); \
 	preempt_disable(); \
 	_raw_spin_lock(lock); \
 	__acquire(lock); \
 } while (0)

 #define _spin_lock_bh(lock) \
 do { \
 	local_bh_disable(); \
 	preempt_disable(); \
 	_raw_spin_lock(lock); \
 	__acquire(lock); \
 } while (0)

 #define _read_lock_irqsave(lock, flags) \
 do {	\
 	local_irq_save(flags); \
 	preempt_disable(); \
 	_raw_read_lock(lock); \
 	__acquire(lock); \
 } while (0)

 #define _read_lock_irq(lock) \
 do { \
 	local_irq_disable(); \
 	preempt_disable(); \
 	_raw_read_lock(lock); \
 	__acquire(lock); \
 } while (0)

 #define _read_lock_bh(lock) \
 do { \
 	local_bh_disable(); \
 	preempt_disable(); \
 	_raw_read_lock(lock); \
 	__acquire(lock); \
 } while (0)

 #define _write_lock_irqsave(lock, flags) \
 do {	\
 	local_irq_save(flags); \
 	preempt_disable(); \
 	_raw_write_lock(lock); \
 	__acquire(lock); \
 } while (0)

 #define _write_lock_irq(lock) \
 do { \
 	local_irq_disable(); \
 	preempt_disable(); \
 	_raw_write_lock(lock); \
 	__acquire(lock); \
 } while (0)

 #define _write_lock_bh(lock) \
 do { \
 	local_bh_disable(); \
 	preempt_disable(); \
 	_raw_write_lock(lock); \
 	__acquire(lock); \
 } while (0)

 #define _spin_unlock_irqrestore(lock, flags) \
 do { \
 	_raw_spin_unlock(lock); \
 	local_irq_restore(flags); \
 	preempt_enable(); \
 	__release(lock); \
 } while (0)

 #define _spin_unlock_irq(lock) \
 do { \
 	_raw_spin_unlock(lock); \
 	local_irq_enable(); \
 	preempt_enable(); \
 	__release(lock); \
 } while (0)

 #define _spin_unlock_bh(lock) \
 do { \
 	_raw_spin_unlock(lock); \
 	preempt_enable(); \
 	local_bh_enable(); \
 	__release(lock); \
 } while (0)

 #define _write_unlock_bh(lock) \
 do { \
 	_raw_write_unlock(lock); \
 	preempt_enable(); \
 	local_bh_enable(); \
 	__release(lock); \
 } while (0)

 #define _read_unlock_irqrestore(lock, flags) \
 do { \
 	_raw_read_unlock(lock); \
 	local_irq_restore(flags); \
 	preempt_enable(); \
 	__release(lock); \
 } while (0)

 #define _write_unlock_irqrestore(lock, flags) \
 do { \
 	_raw_write_unlock(lock); \
 	local_irq_restore(flags); \
 	preempt_enable(); \
 	__release(lock); \
 } while (0)

 #define _read_unlock_irq(lock)	\
 do { \
 	_raw_read_unlock(lock);	\
 	local_irq_enable();	\
 	preempt_enable();	\
 	__release(lock); \
 } while (0)

 #define _read_unlock_bh(lock)	\
 do { \
 	_raw_read_unlock(lock);	\
 	local_bh_enable();	\
 	preempt_enable();	\
 	__release(lock); \
 } while (0)

 #define _write_unlock_irq(lock)	\
 do { \
 	_raw_write_unlock(lock);	\
 	local_irq_enable();	\
 	preempt_enable();	\
 	__release(lock); \
 } while (0)

 #endif /* !SMP */

 /*
  * Define the various spin_lock and rw_lock methods.  Note we define these
  * regardless of whether CONFIG_SMP or CONFIG_PREEMPT are set. The various
  * methods are defined as nops in the case they are not required.
  */
 #define spin_trylock(lock)	__cond_lock(_spin_trylock(lock))
 #define read_trylock(lock)	__cond_lock(_read_trylock(lock))
 #define write_trylock(lock)	__cond_lock(_write_trylock(lock))

 #define spin_lock(lock)		_spin_lock(lock)
 #define write_lock(lock)	_write_lock(lock)
 #define read_lock(lock)		_read_lock(lock)

 #ifdef CONFIG_SMP
 #define spin_lock_irqsave(lock, flags)	flags = _spin_lock_irqsave(lock)
 #define read_lock_irqsave(lock, flags)	flags = _read_lock_irqsave(lock)
 #define write_lock_irqsave(lock, flags)	flags = _write_lock_irqsave(lock)
 #else
 #define spin_lock_irqsave(lock, flags)	_spin_lock_irqsave(lock, flags)
 #define read_lock_irqsave(lock, flags)	_read_lock_irqsave(lock, flags)
 #define write_lock_irqsave(lock, flags)	_write_lock_irqsave(lock, flags)
 #endif

 #define spin_lock_irq(lock)		_spin_lock_irq(lock)
 #define spin_lock_bh(lock)		_spin_lock_bh(lock)

 #define read_lock_irq(lock)		_read_lock_irq(lock)
 #define read_lock_bh(lock)		_read_lock_bh(lock)

 #define write_lock_irq(lock)		_write_lock_irq(lock)
 #define write_lock_bh(lock)		_write_lock_bh(lock)

 #define spin_unlock(lock)	_spin_unlock(lock)
 #define write_unlock(lock)	_write_unlock(lock)
 #define read_unlock(lock)	_read_unlock(lock)

 #define spin_unlock_irqrestore(lock, flags)	_spin_unlock_irqrestore(lock, flags)
 #define spin_unlock_irq(lock)		_spin_unlock_irq(lock)
 #define spin_unlock_bh(lock)		_spin_unlock_bh(lock)

 #define read_unlock_irqrestore(lock, flags)	_read_unlock_irqrestore(lock, flags)
 #define read_unlock_irq(lock)			_read_unlock_irq(lock)
 #define read_unlock_bh(lock)			_read_unlock_bh(lock)

 #define write_unlock_irqrestore(lock, flags)	_write_unlock_irqrestore(lock, flags)
 #define write_unlock_irq(lock)			_write_unlock_irq(lock)
 #define write_unlock_bh(lock)			_write_unlock_bh(lock)

 #define spin_trylock_bh(lock)			__cond_lock(_spin_trylock_bh(lock))

 #define spin_trylock_irq(lock) \
 ({ \
 	local_irq_disable(); \
 	_spin_trylock(lock) ? \
 	1 : ({local_irq_enable(); 0; }); \
 })

 #define spin_trylock_irqsave(lock, flags) \
 ({ \
 	local_irq_save(flags); \
 	_spin_trylock(lock) ? \
 	1 : ({local_irq_restore(flags); 0;}); \
 })

 #ifdef CONFIG_LOCKMETER
 extern void _metered_spin_lock   (spinlock_t *lock);
 extern void _metered_spin_unlock (spinlock_t *lock);
 extern int  _metered_spin_trylock(spinlock_t *lock);
 extern void _metered_read_lock    (rwlock_t *lock);
 extern void _metered_read_unlock  (rwlock_t *lock);
 extern void _metered_write_lock   (rwlock_t *lock);
 extern void _metered_write_unlock (rwlock_t *lock);
 extern int  _metered_read_trylock (rwlock_t *lock);
 extern int  _metered_write_trylock(rwlock_t *lock);
 #endif

 /* "lock on reference count zero" */
 #ifndef ATOMIC_DEC_AND_LOCK
 #include <asm/atomic.h>
 extern int _atomic_dec_and_lock(atomic_t *atomic, spinlock_t *lock);
 #endif

 #define atomic_dec_and_lock(atomic,lock) __cond_lock(_atomic_dec_and_lock(atomic,lock))

 /*
  *  bit-based spin_lock()
  *
  * Don't use this unless you really need to: spin_lock() and spin_unlock()
  * are significantly faster.
  */
 static inline void bit_spin_lock(int bitnum, unsigned long *addr)
 {
 	/*
 	 * Assuming the lock is uncontended, this never enters
 	 * the body of the outer loop. If it is contended, then
 	 * within the inner loop a non-atomic test is used to
 	 * busywait with less bus contention for a good time to
 	 * attempt to acquire the lock bit.
 	 */
 	preempt_disable();
 #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
 	while (test_and_set_bit(bitnum, addr)) {
 		while (test_bit(bitnum, addr)) {
 			preempt_enable();
 			cpu_relax();
 			preempt_disable();
 		}
 	}
 #endif
 	__acquire(bitlock);
 }

 /*
  * Return true if it was acquired
  */
 static inline int bit_spin_trylock(int bitnum, unsigned long *addr)
 {
 	preempt_disable();
 #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
 	if (test_and_set_bit(bitnum, addr)) {
 		preempt_enable();
 		return 0;
 	}
 #endif
 	__acquire(bitlock);
 	return 1;
 }

 /*
  *  bit-based spin_unlock()
  */
 static inline void bit_spin_unlock(int bitnum, unsigned long *addr)
 {
 #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
 	BUG_ON(!test_bit(bitnum, addr));
 	smp_mb__before_clear_bit();
 	clear_bit(bitnum, addr);
 #endif
 	preempt_enable();
 	__release(bitlock);
 }

 /*
  * Return true if the lock is held.
  */
 static inline int bit_spin_is_locked(int bitnum, unsigned long *addr)
 {
 #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
 	return test_bit(bitnum, addr);
 #elif defined CONFIG_PREEMPT
 	return preempt_count();
 #else
 	return 1;
 #endif
 }

 #define DEFINE_SPINLOCK(x) spinlock_t x = SPIN_LOCK_UNLOCKED
 #define DEFINE_RWLOCK(x) rwlock_t x = RW_LOCK_UNLOCKED

 /**
  * spin_can_lock - would spin_trylock() succeed?
  * @lock: the spinlock in question.
  */
 #define spin_can_lock(lock)		(!spin_is_locked(lock))

 #endif /* __LINUX_SPINLOCK_H */
	#ifndef __LINUX_SPINLOCK_H
	#define __LINUX_SPINLOCK_H

	/*
	* include/linux/spinlock.h - generic locking declarations
	*/

	#include <linux/config.h>
	#include <linux/preempt.h>
	#include <linux/linkage.h>
	#include <linux/compiler.h>
	#include <linux/thread_info.h>
	#include <linux/kernel.h>
	#include <linux/stringify.h>

	#include <asm/processor.h> /* for cpu relax */
	#include <asm/system.h>

	/*
	* Must define these before including other files, inline functions need them
	*/
	#define LOCK_SECTION_NAME \
	".text.lock." __stringify(KBUILD_BASENAME)

	#define LOCK_SECTION_START(extra) \
	".subsection 1\n\t" \
	extra \
	".ifndef " LOCK_SECTION_NAME "\n\t" \
	LOCK_SECTION_NAME ":\n\t" \
	".endif\n"

	#define LOCK_SECTION_END \
	".previous\n\t"

	#define __lockfunc fastcall __attribute__((section(".spinlock.text")))

	/*
	* If CONFIG_SMP is set, pull in the _raw_* definitions
	*/
	#ifdef CONFIG_SMP

	#define assert_spin_locked(x) BUG_ON(!spin_is_locked(x))
	#include <asm/spinlock.h>

	int __lockfunc _spin_trylock(spinlock_t *lock);
	int __lockfunc _read_trylock(rwlock_t *lock);
	int __lockfunc _write_trylock(rwlock_t *lock);

	void __lockfunc _spin_lock(spinlock_t *lock) __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_unlock(spinlock_t *lock) __releases(spinlock_t);
	void __lockfunc _read_unlock(rwlock_t *lock) __releases(rwlock_t);
	void __lockfunc _write_unlock(rwlock_t *lock) __releases(rwlock_t);

	unsigned long __lockfunc _spin_lock_irqsave(spinlock_t *lock) __acquires(spinlock_t);
	unsigned long __lockfunc _read_lock_irqsave(rwlock_t *lock) __acquires(rwlock_t);
	unsigned long __lockfunc _write_lock_irqsave(rwlock_t *lock) __acquires(rwlock_t);

	void __lockfunc _spin_lock_irq(spinlock_t *lock) __acquires(spinlock_t);
	void __lockfunc _spin_lock_bh(spinlock_t *lock) __acquires(spinlock_t);
	void __lockfunc _read_lock_irq(rwlock_t *lock) __acquires(rwlock_t);
	void __lockfunc _read_lock_bh(rwlock_t *lock) __acquires(rwlock_t);
	void __lockfunc _write_lock_irq(rwlock_t *lock) __acquires(rwlock_t);
	void __lockfunc _write_lock_bh(rwlock_t *lock) __acquires(rwlock_t);

	void __lockfunc _spin_unlock_irqrestore(spinlock_t *lock, unsigned long flags) __releases(spinlock_t);
	void __lockfunc _spin_unlock_irq(spinlock_t *lock) __releases(spinlock_t);
	void __lockfunc _spin_unlock_bh(spinlock_t *lock) __releases(spinlock_t);
	void __lockfunc _read_unlock_irqrestore(rwlock_t *lock, unsigned long flags) __releases(rwlock_t);
	void __lockfunc _read_unlock_irq(rwlock_t *lock) __releases(rwlock_t);
	void __lockfunc _read_unlock_bh(rwlock_t *lock) __releases(rwlock_t);
	void __lockfunc _write_unlock_irqrestore(rwlock_t *lock, unsigned long flags) __releases(rwlock_t);
	void __lockfunc _write_unlock_irq(rwlock_t *lock) __releases(rwlock_t);
	void __lockfunc _write_unlock_bh(rwlock_t *lock) __releases(rwlock_t);

	int __lockfunc _spin_trylock_bh(spinlock_t *lock);
	int __lockfunc generic_raw_read_trylock(rwlock_t *lock);
	int in_lock_functions(unsigned long addr);

	#else

	#define in_lock_functions(ADDR) 0

	#if !defined(CONFIG_PREEMPT) && !defined(CONFIG_DEBUG_SPINLOCK)
	# define _atomic_dec_and_lock(atomic,lock) atomic_dec_and_test(atomic)
	# define ATOMIC_DEC_AND_LOCK
	#endif

	#ifdef CONFIG_DEBUG_SPINLOCK

	#define SPINLOCK_MAGIC 0x1D244B3C
	typedef struct {
	unsigned long magic;
	volatile unsigned long lock;
	volatile unsigned int babble;
	const char *module;
	char *owner;
	int oline;
	} spinlock_t;
	#define SPIN_LOCK_UNLOCKED (spinlock_t) { SPINLOCK_MAGIC, 0, 10, __FILE__ , NULL, 0}

	#define spin_lock_init(x) \
	do { \
	(x)->magic = SPINLOCK_MAGIC; \
	(x)->lock = 0; \
	(x)->babble = 5; \
	(x)->module = __FILE__; \
	(x)->owner = NULL; \
	(x)->oline = 0; \
	} while (0)

	#define CHECK_LOCK(x) \
	do { \
	if ((x)->magic != SPINLOCK_MAGIC) { \
	printk(KERN_ERR "%s:%d: spin_is_locked on uninitialized spinlock %p.\n", \
	__FILE__, __LINE__, (x)); \
	} \
	} while(0)

	#define _raw_spin_lock(x) \
	do { \
	CHECK_LOCK(x); \
	if ((x)->lock&&(x)->babble) { \
	(x)->babble--; \
	printk("%s:%d: spin_lock(%s:%p) already locked by %s/%d\n", \
	__FILE__,__LINE__, (x)->module, \
	(x), (x)->owner, (x)->oline); \
	} \
	(x)->lock = 1; \
	(x)->owner = __FILE__; \
	(x)->oline = __LINE__; \
	} while (0)

	/* without debugging, spin_is_locked on UP always says
	* FALSE. --> printk if already locked. */
	#define spin_is_locked(x) \
	({ \
	CHECK_LOCK(x); \
	if ((x)->lock&&(x)->babble) { \
	(x)->babble--; \
	printk("%s:%d: spin_is_locked(%s:%p) already locked by %s/%d\n", \
	__FILE__,__LINE__, (x)->module, \
	(x), (x)->owner, (x)->oline); \
	} \
	0; \
	})

	/* with debugging, assert_spin_locked() on UP does check
	* the lock value properly */
	#define assert_spin_locked(x) \
	({ \
	CHECK_LOCK(x); \
	BUG_ON(!(x)->lock); \
	})

	/* without debugging, spin_trylock on UP always says
	* TRUE. --> printk if already locked. */
	#define _raw_spin_trylock(x) \
	({ \
	CHECK_LOCK(x); \
	if ((x)->lock&&(x)->babble) { \
	(x)->babble--; \
	printk("%s:%d: spin_trylock(%s:%p) already locked by %s/%d\n", \
	__FILE__,__LINE__, (x)->module, \
	(x), (x)->owner, (x)->oline); \
	} \
	(x)->lock = 1; \
	(x)->owner = __FILE__; \
	(x)->oline = __LINE__; \
	1; \
	})

	#define spin_unlock_wait(x) \
	do { \
	CHECK_LOCK(x); \
	if ((x)->lock&&(x)->babble) { \
	(x)->babble--; \
	printk("%s:%d: spin_unlock_wait(%s:%p) owned by %s/%d\n", \
	__FILE__,__LINE__, (x)->module, (x), \
	(x)->owner, (x)->oline); \
	}\
	} while (0)

	#define _raw_spin_unlock(x) \
	do { \
	CHECK_LOCK(x); \
	if (!(x)->lock&&(x)->babble) { \
	(x)->babble--; \
	printk("%s:%d: spin_unlock(%s:%p) not locked\n", \
	__FILE__,__LINE__, (x)->module, (x));\
	} \
	(x)->lock = 0; \
	} while (0)
	#else
	/*
	* gcc versions before ~2.95 have a nasty bug with empty initializers.
	*/
	#if (__GNUC__ > 2)
	typedef struct { } spinlock_t;
	#define SPIN_LOCK_UNLOCKED (spinlock_t) { }
	#else
	typedef struct { int gcc_is_buggy; } spinlock_t;
	#define SPIN_LOCK_UNLOCKED (spinlock_t) { 0 }
	#endif

	/*
	* If CONFIG_SMP is unset, declare the _raw_* definitions as nops
	*/
	#define spin_lock_init(lock) do { (void)(lock); } while(0)
	#define _raw_spin_lock(lock) do { (void)(lock); } while(0)
	#define spin_is_locked(lock) ((void)(lock), 0)
	#define assert_spin_locked(lock) do { (void)(lock); } while(0)
	#define _raw_spin_trylock(lock) (((void)(lock), 1))
	#define spin_unlock_wait(lock) (void)(lock)
	#define _raw_spin_unlock(lock) do { (void)(lock); } while(0)
	#endif /* CONFIG_DEBUG_SPINLOCK */

	/* RW spinlocks: No debug version */

	#if (__GNUC__ > 2)
	typedef struct { } rwlock_t;
	#define RW_LOCK_UNLOCKED (rwlock_t) { }
	#else
	typedef struct { int gcc_is_buggy; } rwlock_t;
	#define RW_LOCK_UNLOCKED (rwlock_t) { 0 }
	#endif

	#define rwlock_init(lock) do { (void)(lock); } while(0)
	#define _raw_read_lock(lock) do { (void)(lock); } while(0)
	#define _raw_read_unlock(lock) do { (void)(lock); } while(0)
	#define _raw_write_lock(lock) do { (void)(lock); } while(0)
	#define _raw_write_unlock(lock) do { (void)(lock); } while(0)
	#define read_can_lock(lock) (((void)(lock), 1))
	#define write_can_lock(lock) (((void)(lock), 1))
	#define _raw_read_trylock(lock) ({ (void)(lock); (1); })
	#define _raw_write_trylock(lock) ({ (void)(lock); (1); })

	#define _spin_trylock(lock) ({preempt_disable(); _raw_spin_trylock(lock) ? \
	1 : ({preempt_enable(); 0;});})

	#define _read_trylock(lock) ({preempt_disable();_raw_read_trylock(lock) ? \
	1 : ({preempt_enable(); 0;});})

	#define _write_trylock(lock) ({preempt_disable(); _raw_write_trylock(lock) ? \
	1 : ({preempt_enable(); 0;});})

	#define _spin_trylock_bh(lock) ({preempt_disable(); local_bh_disable(); \
	_raw_spin_trylock(lock) ? \
	1 : ({preempt_enable(); local_bh_enable(); 0;});})

	#define _spin_lock(lock) \
	do { \
	preempt_disable(); \
	_raw_spin_lock(lock); \
	__acquire(lock); \
	} while(0)

	#define _write_lock(lock) \
	do { \
	preempt_disable(); \
	_raw_write_lock(lock); \
	__acquire(lock); \
	} while(0)

	#define _read_lock(lock) \
	do { \
	preempt_disable(); \
	_raw_read_lock(lock); \
	__acquire(lock); \
	} while(0)

	#define _spin_unlock(lock) \
	do { \
	_raw_spin_unlock(lock); \
	preempt_enable(); \
	__release(lock); \
	} while (0)

	#define _write_unlock(lock) \
	do { \
	_raw_write_unlock(lock); \
	preempt_enable(); \
	__release(lock); \
	} while(0)

	#define _read_unlock(lock) \
	do { \
	_raw_read_unlock(lock); \
	preempt_enable(); \
	__release(lock); \
	} while(0)

	#define _spin_lock_irqsave(lock, flags) \
	do { \
	local_irq_save(flags); \
	preempt_disable(); \
	_raw_spin_lock(lock); \
	__acquire(lock); \
	} while (0)

	#define _spin_lock_irq(lock) \
	do { \
	local_irq_disable(); \
	preempt_disable(); \
	_raw_spin_lock(lock); \
	__acquire(lock); \
	} while (0)

	#define _spin_lock_bh(lock) \
	do { \
	local_bh_disable(); \
	preempt_disable(); \
	_raw_spin_lock(lock); \
	__acquire(lock); \
	} while (0)

	#define _read_lock_irqsave(lock, flags) \
	do { \
	local_irq_save(flags); \
	preempt_disable(); \
	_raw_read_lock(lock); \
	__acquire(lock); \
	} while (0)

	#define _read_lock_irq(lock) \
	do { \
	local_irq_disable(); \
	preempt_disable(); \
	_raw_read_lock(lock); \
	__acquire(lock); \
	} while (0)

	#define _read_lock_bh(lock) \
	do { \
	local_bh_disable(); \
	preempt_disable(); \
	_raw_read_lock(lock); \
	__acquire(lock); \
	} while (0)

	#define _write_lock_irqsave(lock, flags) \
	do { \
	local_irq_save(flags); \
	preempt_disable(); \
	_raw_write_lock(lock); \
	__acquire(lock); \
	} while (0)

	#define _write_lock_irq(lock) \
	do { \
	local_irq_disable(); \
	preempt_disable(); \
	_raw_write_lock(lock); \
	__acquire(lock); \
	} while (0)

	#define _write_lock_bh(lock) \
	do { \
	local_bh_disable(); \
	preempt_disable(); \
	_raw_write_lock(lock); \
	__acquire(lock); \
	} while (0)

	#define _spin_unlock_irqrestore(lock, flags) \
	do { \
	_raw_spin_unlock(lock); \
	local_irq_restore(flags); \
	preempt_enable(); \
	__release(lock); \
	} while (0)

	#define _spin_unlock_irq(lock) \
	do { \
	_raw_spin_unlock(lock); \
	local_irq_enable(); \
	preempt_enable(); \
	__release(lock); \
	} while (0)

	#define _spin_unlock_bh(lock) \
	do { \
	_raw_spin_unlock(lock); \
	preempt_enable(); \
	local_bh_enable(); \
	__release(lock); \
	} while (0)

	#define _write_unlock_bh(lock) \
	do { \
	_raw_write_unlock(lock); \
	preempt_enable(); \
	local_bh_enable(); \
	__release(lock); \
	} while (0)

	#define _read_unlock_irqrestore(lock, flags) \
	do { \
	_raw_read_unlock(lock); \
	local_irq_restore(flags); \
	preempt_enable(); \
	__release(lock); \
	} while (0)

	#define _write_unlock_irqrestore(lock, flags) \
	do { \
	_raw_write_unlock(lock); \
	local_irq_restore(flags); \
	preempt_enable(); \
	__release(lock); \
	} while (0)

	#define _read_unlock_irq(lock) \
	do { \
	_raw_read_unlock(lock); \
	local_irq_enable(); \
	preempt_enable(); \
	__release(lock); \
	} while (0)

	#define _read_unlock_bh(lock) \
	do { \
	_raw_read_unlock(lock); \
	local_bh_enable(); \
	preempt_enable(); \
	__release(lock); \
	} while (0)

	#define _write_unlock_irq(lock) \
	do { \
	_raw_write_unlock(lock); \
	local_irq_enable(); \
	preempt_enable(); \
	__release(lock); \
	} while (0)

	#endif /* !SMP */

	/*
	* Define the various spin_lock and rw_lock methods. Note we define these
	* regardless of whether CONFIG_SMP or CONFIG_PREEMPT are set. The various
	* methods are defined as nops in the case they are not required.
	*/
	#define spin_trylock(lock) __cond_lock(_spin_trylock(lock))
	#define read_trylock(lock) __cond_lock(_read_trylock(lock))
	#define write_trylock(lock) __cond_lock(_write_trylock(lock))

	#define spin_lock(lock) _spin_lock(lock)
	#define write_lock(lock) _write_lock(lock)
	#define read_lock(lock) _read_lock(lock)

	#ifdef CONFIG_SMP
	#define spin_lock_irqsave(lock, flags) flags = _spin_lock_irqsave(lock)
	#define read_lock_irqsave(lock, flags) flags = _read_lock_irqsave(lock)
	#define write_lock_irqsave(lock, flags) flags = _write_lock_irqsave(lock)
	#else
	#define spin_lock_irqsave(lock, flags) _spin_lock_irqsave(lock, flags)
	#define read_lock_irqsave(lock, flags) _read_lock_irqsave(lock, flags)
	#define write_lock_irqsave(lock, flags) _write_lock_irqsave(lock, flags)
	#endif

	#define spin_lock_irq(lock) _spin_lock_irq(lock)
	#define spin_lock_bh(lock) _spin_lock_bh(lock)

	#define read_lock_irq(lock) _read_lock_irq(lock)
	#define read_lock_bh(lock) _read_lock_bh(lock)

	#define write_lock_irq(lock) _write_lock_irq(lock)
	#define write_lock_bh(lock) _write_lock_bh(lock)

	#define spin_unlock(lock) _spin_unlock(lock)
	#define write_unlock(lock) _write_unlock(lock)
	#define read_unlock(lock) _read_unlock(lock)

	#define spin_unlock_irqrestore(lock, flags) _spin_unlock_irqrestore(lock, flags)
	#define spin_unlock_irq(lock) _spin_unlock_irq(lock)
	#define spin_unlock_bh(lock) _spin_unlock_bh(lock)

	#define read_unlock_irqrestore(lock, flags) _read_unlock_irqrestore(lock, flags)
	#define read_unlock_irq(lock) _read_unlock_irq(lock)
	#define read_unlock_bh(lock) _read_unlock_bh(lock)

	#define write_unlock_irqrestore(lock, flags) _write_unlock_irqrestore(lock, flags)
	#define write_unlock_irq(lock) _write_unlock_irq(lock)
	#define write_unlock_bh(lock) _write_unlock_bh(lock)

	#define spin_trylock_bh(lock) __cond_lock(_spin_trylock_bh(lock))

	#define spin_trylock_irq(lock) \
	({ \
	local_irq_disable(); \
	_spin_trylock(lock) ? \
	1 : ({local_irq_enable(); 0; }); \
	})

	#define spin_trylock_irqsave(lock, flags) \
	({ \
	local_irq_save(flags); \
	_spin_trylock(lock) ? \
	1 : ({local_irq_restore(flags); 0;}); \
	})

	#ifdef CONFIG_LOCKMETER
	extern void _metered_spin_lock (spinlock_t *lock);
	extern void _metered_spin_unlock (spinlock_t *lock);
	extern int _metered_spin_trylock(spinlock_t *lock);
	extern void _metered_read_lock (rwlock_t *lock);
	extern void _metered_read_unlock (rwlock_t *lock);
	extern void _metered_write_lock (rwlock_t *lock);
	extern void _metered_write_unlock (rwlock_t *lock);
	extern int _metered_read_trylock (rwlock_t *lock);
	extern int _metered_write_trylock(rwlock_t *lock);
	#endif

	/* "lock on reference count zero" */
	#ifndef ATOMIC_DEC_AND_LOCK
	#include <asm/atomic.h>
	extern int _atomic_dec_and_lock(atomic_t atomic, spinlock_t lock);
	#endif

	#define atomic_dec_and_lock(atomic,lock) __cond_lock(_atomic_dec_and_lock(atomic,lock))

	/*
	* bit-based spin_lock()
	*
	* Don't use this unless you really need to: spin_lock() and spin_unlock()
	* are significantly faster.
	*/
	static inline void bit_spin_lock(int bitnum, unsigned long *addr)
	{
	/*
	* Assuming the lock is uncontended, this never enters
	* the body of the outer loop. If it is contended, then
	* within the inner loop a non-atomic test is used to
	* busywait with less bus contention for a good time to
	* attempt to acquire the lock bit.
	*/
	preempt_disable();
	#if defined(CONFIG_SMP) \|\| defined(CONFIG_DEBUG_SPINLOCK)
	while (test_and_set_bit(bitnum, addr)) {
	while (test_bit(bitnum, addr)) {
	preempt_enable();
	cpu_relax();
	preempt_disable();
	}
	}
	#endif
	__acquire(bitlock);
	}

	/*
	* Return true if it was acquired
	*/
	static inline int bit_spin_trylock(int bitnum, unsigned long *addr)
	{
	preempt_disable();
	#if defined(CONFIG_SMP) \|\| defined(CONFIG_DEBUG_SPINLOCK)
	if (test_and_set_bit(bitnum, addr)) {
	preempt_enable();
	return 0;
	}
	#endif
	__acquire(bitlock);
	return 1;
	}

	/*
	* bit-based spin_unlock()
	*/
	static inline void bit_spin_unlock(int bitnum, unsigned long *addr)
	{
	#if defined(CONFIG_SMP) \|\| defined(CONFIG_DEBUG_SPINLOCK)
	BUG_ON(!test_bit(bitnum, addr));
	smp_mb__before_clear_bit();
	clear_bit(bitnum, addr);
	#endif
	preempt_enable();
	__release(bitlock);
	}

	/*
	* Return true if the lock is held.
	*/
	static inline int bit_spin_is_locked(int bitnum, unsigned long *addr)
	{
	#if defined(CONFIG_SMP) \|\| defined(CONFIG_DEBUG_SPINLOCK)
	return test_bit(bitnum, addr);
	#elif defined CONFIG_PREEMPT
	return preempt_count();
	#else
	return 1;
	#endif
	}

	#define DEFINE_SPINLOCK(x) spinlock_t x = SPIN_LOCK_UNLOCKED
	#define DEFINE_RWLOCK(x) rwlock_t x = RW_LOCK_UNLOCKED

	/**
	* spin_can_lock - would spin_trylock() succeed?
	* @lock: the spinlock in question.
	*/
	#define spin_can_lock(lock) (!spin_is_locked(lock))

	#endif /* __LINUX_SPINLOCK_H */