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#ifndef __ASM_MIPS_SPINLOCK_H
#define __ASM_MIPS_SPINLOCK_H

#ifndef __SMP__

/* gcc 2.7.2 can crash initializing an empty structure.  For now we
   try to do though ...  */
typedef struct { } spinlock_t;
#define SPIN_LOCK_UNLOCKED { }

#define spin_lock_init(lock)	do { } while(0)
#define spin_lock(lock)		do { } while(0)
#define spin_trylock(lock)	do { } while(0)
#define spin_unlock_wait(lock)	do { } while(0)
#define spin_unlock(lock)	do { } while(0)
#define spin_lock_irq(lock)	cli()
#define spin_unlock_irq(lock)	sti()

#define spin_lock_irqsave(lock, flags)		save_and_cli(flags)
#define spin_unlock_irqrestore(lock, flags)	restore_flags(flags)

/*
 * Read-write spinlocks, allowing multiple readers
 * but only one writer.
 *
 * NOTE! it is quite common to have readers in interrupts
 * but no interrupt writers. For those circumstances we
 * can "mix" irq-safe locks - any writer needs to get a
 * irq-safe write-lock, but readers can get non-irqsafe
 * read-locks.
 */
typedef struct { } rwlock_t;
#define RW_LOCK_UNLOCKED { }

#define read_lock(lock)		do { } while(0)
#define read_unlock(lock)	do { } while(0)
#define write_lock(lock)	do { } while(0)
#define write_unlock(lock)	do { } while(0)
#define read_lock_irq(lock)	cli()
#define read_unlock_irq(lock)	sti()
#define write_lock_irq(lock)	cli()
#define write_unlock_irq(lock)	sti()

#define read_lock_irqsave(lock, flags)		save_and_cli(flags)
#define read_unlock_irqrestore(lock, flags)	restore_flags(flags)
#define write_lock_irqsave(lock, flags)		save_and_cli(flags)
#define write_unlock_irqrestore(lock, flags)	restore_flags(flags)

#else

#error "Nix SMP on MIPS"

#endif /* SMP */
#endif /* __ASM_MIPS_SPINLOCK_H */