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#ifndef __ASM_SPINLOCK_H
#define __ASM_SPINLOCK_H
#ifndef __SMP__
/*
* To be safe, we assume the only compiler that can cope with
* empty initialisers is EGCS.
*/
#if (__GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 90))
#define EMPTY_INIT_OK
#endif
/*
* Your basic spinlocks, allowing only a single CPU anywhere
*/
#ifdef EMPTY_INIT_OK
typedef struct { } spinlock_t;
# define SPIN_LOCK_UNLOCKED (spinlock_t) { }
#else
typedef unsigned char spinlock_t;
# define SPIN_LOCK_UNLOCKED 0
#endif
#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) \
do { __save_flags_cli(flags); } while (0)
#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.
*/
#ifdef EMPTY_INIT_OK
typedef struct { } rwlock_t;
# define RW_LOCK_UNLOCKED (rwlock_t) { }
#else
typedef unsigned char rwlock_t;
# define RW_LOCK_UNLOCKED 0
#endif
#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) \
do { __save_flags_cli(flags); } while (0)
#define read_unlock_irqrestore(lock, flags) \
restore_flags(flags)
#define write_lock_irqsave(lock, flags) \
do { __save_flags_cli(flags); } while (0)
#define write_unlock_irqrestore(lock, flags) \
restore_flags(flags)
#else
#error ARM architecture does not support spin locks
#endif /* SMP */
#endif /* __ASM_SPINLOCK_H */
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