build_lock_ops.c

#define BUILD_LOCK_OPS(op, locktype)					\
void __lockfunc _##op##_lock(locktype##_t *lock)			\
{									\
	preempt_disable();						\
	for (;;) {							\
		if (likely(_raw_##op##_trylock(lock)))			\
			break;						\
		preempt_enable();					\
		if (!(lock)->break_lock)				\
			(lock)->break_lock = 1;				\
		while (!op##_can_lock(lock) && (lock)->break_lock)	\
			cpu_relax();					\
		preempt_disable();					\
	}								\
}									\
									\
EXPORT_SYMBOL(_##op##_lock);						\
									\
unsigned long __lockfunc _##op##_lock_irqsave(locktype##_t *lock)	\
{									\
	unsigned long flags;						\
									\
	preempt_disable();						\
	for (;;) {							\
		local_irq_save(flags);					\
		if (likely(_raw_##op##_trylock(lock)))			\
			break;						\
		local_irq_restore(flags);				\
									\
		preempt_enable();					\
		if (!(lock)->break_lock)				\
			(lock)->break_lock = 1;				\
		while (!op##_can_lock(lock) && (lock)->break_lock)	\
			cpu_relax();					\
		preempt_disable();					\
	}								\
	return flags;							\
}									\
									\
EXPORT_SYMBOL(_##op##_lock_irqsave);					\
									\
void __lockfunc _##op##_lock_irq(locktype##_t *lock)			\
{									\
	_##op##_lock_irqsave(lock);					\
}									\
									\
EXPORT_SYMBOL(_##op##_lock_irq);					\
									\
void __lockfunc _##op##_lock_bh(locktype##_t *lock)			\
{									\
	unsigned long flags;						\
									\
	/*							*/	\
	/* Careful: we must exclude softirqs too, hence the	*/	\
	/* irq-disabling. We use the generic preemption-aware	*/	\
	/* function:						*/	\
	/**/								\
	flags = _##op##_lock_irqsave(lock);				\
	local_bh_disable();						\
	local_irq_restore(flags);					\
}									\
									\
EXPORT_SYMBOL(_##op##_lock_bh)