spinlock.h

umon bootloader source code, support mips cpu.

	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_no_resched(); \
	local_bh_enable(); \
	__release(lock); \
} while (0)

#define _write_unlock_bh(lock) \
do { \
	_raw_write_unlock(lock); \
	preempt_enable_no_resched(); \
	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);	\
	preempt_enable_no_resched();	\
	local_bh_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 */