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#ifndef __ASM_SPINLOCK_H
#define __ASM_SPINLOCK_H
/*
* 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_STRUCT struct { }
#define EMPTY_STRUCT_INIT(t) (t) { }
#else
#define EMPTY_STRUCT unsigned char
#define EMPTY_STRUCT_INIT(t) (t) 0
#endif
/*
* These are the generic versions of the spinlocks
* and read-write locks.. We should actually do a
* <linux/spinlock.h> with all of this. Oh, well.
*/
#define spin_lock_irqsave(lock, flags) do { local_irq_save(flags); spin_lock(lock); } while (0)
#define spin_lock_irq(lock) do { local_irq_disable(); spin_lock(lock); } while (0)
#define spin_lock_bh(lock) do { local_bh_disable(); spin_lock(lock); } while (0)
#define read_lock_irqsave(lock, flags) do { local_irq_save(flags); read_lock(lock); } while (0)
#define read_lock_irq(lock) do { local_irq_disable(); read_lock(lock); } while (0)
#define read_lock_bh(lock) do { local_bh_disable(); read_lock(lock); } while (0)
#define write_lock_irqsave(lock, flags) do { local_irq_save(flags); write_lock(lock); } while (0)
#define write_lock_irq(lock) do { local_irq_disable(); write_lock(lock); } while (0)
#define write_lock_bh(lock) do { local_bh_disable(); write_lock(lock); } while (0)
#define spin_unlock_irqrestore(lock, flags) do { spin_unlock(lock); local_irq_restore(flags); } while (0)
#define spin_unlock_irq(lock) do { spin_unlock(lock); local_irq_enable(); } while (0)
#define spin_unlock_bh(lock) do { spin_unlock(lock); local_bh_enable(); } while (0)
#define read_unlock_irqrestore(lock, flags) do { read_unlock(lock); local_irq_restore(flags); } while (0)
#define read_unlock_irq(lock) do { read_unlock(lock); local_irq_enable(); } while (0)
#define read_unlock_bh(lock) do { read_unlock(lock); local_bh_enable(); } while (0)
#define write_unlock_irqrestore(lock, flags) do { write_unlock(lock); local_irq_restore(flags); } while (0)
#define write_unlock_irq(lock) do { write_unlock(lock); local_irq_enable(); } while (0)
#define write_unlock_bh(lock) do { write_unlock(lock); local_bh_enable(); } while (0)
#ifndef __SMP__
#define DEBUG_SPINLOCKS 0 /* 0 == no debugging, 1 == maintain lock state, 2 == full debugging */
#if (DEBUG_SPINLOCKS < 1)
/*
* Your basic spinlocks, allowing only a single CPU anywhere
*/
typedef EMPTY_STRUCT spinlock_t;
#define SPIN_LOCK_UNLOCKED EMPTY_STRUCT_INIT(spinlock_t)
#define spin_lock_init(lock) do { } while(0)
#define spin_lock(lock) do { } while(0)
#define spin_trylock(lock) (1)
#define spin_unlock_wait(lock) do { } while(0)
#define spin_unlock(lock) do { } while(0)
#elif (DEBUG_SPINLOCKS < 2)
typedef struct {
volatile unsigned int lock;
} spinlock_t;
#define SPIN_LOCK_UNLOCKED (pinlock_t) { 0 }
#define spin_lock_init(x) do { (x)->lock = 0; } while (0)
#define spin_lock(x) do { (x)->lock = 1; } while (0)
#define spin_trylock(lock) (!test_and_set_bit(0,(lock)))
#define spin_unlock_wait(x) do { } while (0)
#define spin_unlock(x) do { (x)->lock = 0; } while (0)
#else /* (DEBUG_SPINLOCKS >= 2) */
typedef struct {
volatule unsigned int lock;
volatile unsigned int babble;
const char *module;
} spinlock_t;
#define SPIN_LOCK_UNLOCKED (spinlock_t) { 0, 25, __BASE_FILE__ }
#include <linux/kernel.h>
#define spin_lock_init(x) do { (x)->lock = 0; } while (0)
#define spin_trylock(lock) (!test_and_set_bit(0,(lock)))
#define spin_lock(x) do {unsigned long __spinflags; save_flags(__spinflags); cli(); if ((x)->lock&&(x)->babble) {printk("%s:%d: spin_lock(%s:%p) already locked\n", __BASE_FILE__,__LINE__, (x)->module, (x));(x)->babble--;} (x)->lock = 1; restore_flags(__spinflags);} while (0)
#define spin_unlock_wait(x) do {unsigned long __spinflags; save_flags(__spinflags); cli(); if ((x)->lock&&(x)->babble) {printk("%s:%d: spin_unlock_wait(%s:%p) deadlock\n", __BASE_FILE__,__LINE__, (x)->module, (x));(x)->babble--;} restore_flags(__spinflags);} while (0)
#define spin_unlock(x) do {unsigned long __spinflags; save_flags(__spinflags); cli(); if (!(x)->lock&&(x)->babble) {printk("%s:%d: spin_unlock(%s:%p) not locked\n", __BASE_FILE__,__LINE__, (x)->module, (x));(x)->babble--;} (x)->lock = 0; restore_flags(__spinflags);} while (0)
#endif
/*
* 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 EMPTY_STRUCT rwlock_t;
#define RW_LOCK_UNLOCKED EMPTY_STRUCT_INIT(rwlock_t)
#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)
#else
#error ARM architecture does not support spin locks
#endif /* SMP */
#endif /* __ASM_SPINLOCK_H */
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