178 lines
		
	
	
		
			3.5 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			178 lines
		
	
	
		
			3.5 KiB
		
	
	
	
		
			C
		
	
	
	
| /*
 | |
|  *  linux/include/asm-arm/atomic.h
 | |
|  *
 | |
|  *  Copyright (c) 1996 Russell King.
 | |
|  *
 | |
|  * This program is free software; you can redistribute it and/or modify
 | |
|  * it under the terms of the GNU General Public License version 2 as
 | |
|  * published by the Free Software Foundation.
 | |
|  *
 | |
|  *  Changelog:
 | |
|  *   27-06-1996	RMK	Created
 | |
|  *   13-04-1997	RMK	Made functions atomic!
 | |
|  *   07-12-1997	RMK	Upgraded for v2.1.
 | |
|  *   26-08-1998	PJB	Added #ifdef __KERNEL__
 | |
|  */
 | |
| #ifndef __ASM_ARM_ATOMIC_H
 | |
| #define __ASM_ARM_ATOMIC_H
 | |
| 
 | |
| #ifdef CONFIG_SMP
 | |
| #error SMP not supported
 | |
| #endif
 | |
| 
 | |
| typedef struct { volatile int counter; } atomic_t;
 | |
| #if BITS_PER_LONG == 32
 | |
| typedef struct { volatile long long counter; } atomic64_t;
 | |
| #else /* BIT_PER_LONG == 32 */
 | |
| typedef struct { volatile long counter; } atomic64_t;
 | |
| #endif
 | |
| 
 | |
| #define ATOMIC_INIT(i)	{ (i) }
 | |
| 
 | |
| #ifdef __KERNEL__
 | |
| #include <asm/proc-armv/system.h>
 | |
| 
 | |
| #define atomic_read(v)	((v)->counter)
 | |
| #define atomic_set(v, i)	(((v)->counter) = (i))
 | |
| #define atomic64_read(v)	atomic_read(v)
 | |
| #define atomic64_set(v, i)	atomic_set(v, i)
 | |
| 
 | |
| static inline void atomic_add(int i, volatile atomic_t *v)
 | |
| {
 | |
| 	unsigned long flags = 0;
 | |
| 
 | |
| 	local_irq_save(flags);
 | |
| 	v->counter += i;
 | |
| 	local_irq_restore(flags);
 | |
| }
 | |
| 
 | |
| static inline void atomic_sub(int i, volatile atomic_t *v)
 | |
| {
 | |
| 	unsigned long flags = 0;
 | |
| 
 | |
| 	local_irq_save(flags);
 | |
| 	v->counter -= i;
 | |
| 	local_irq_restore(flags);
 | |
| }
 | |
| 
 | |
| static inline void atomic_inc(volatile atomic_t *v)
 | |
| {
 | |
| 	unsigned long flags = 0;
 | |
| 
 | |
| 	local_irq_save(flags);
 | |
| 	v->counter += 1;
 | |
| 	local_irq_restore(flags);
 | |
| }
 | |
| 
 | |
| static inline void atomic_dec(volatile atomic_t *v)
 | |
| {
 | |
| 	unsigned long flags = 0;
 | |
| 
 | |
| 	local_irq_save(flags);
 | |
| 	v->counter -= 1;
 | |
| 	local_irq_restore(flags);
 | |
| }
 | |
| 
 | |
| static inline int atomic_dec_and_test(volatile atomic_t *v)
 | |
| {
 | |
| 	unsigned long flags = 0;
 | |
| 	int val;
 | |
| 
 | |
| 	local_irq_save(flags);
 | |
| 	val = v->counter;
 | |
| 	v->counter = val -= 1;
 | |
| 	local_irq_restore(flags);
 | |
| 
 | |
| 	return val == 0;
 | |
| }
 | |
| 
 | |
| static inline int atomic_add_negative(int i, volatile atomic_t *v)
 | |
| {
 | |
| 	unsigned long flags = 0;
 | |
| 	int val;
 | |
| 
 | |
| 	local_irq_save(flags);
 | |
| 	val = v->counter;
 | |
| 	v->counter = val += i;
 | |
| 	local_irq_restore(flags);
 | |
| 
 | |
| 	return val < 0;
 | |
| }
 | |
| 
 | |
| static inline void atomic_clear_mask(unsigned long mask, unsigned long *addr)
 | |
| {
 | |
| 	unsigned long flags = 0;
 | |
| 
 | |
| 	local_irq_save(flags);
 | |
| 	*addr &= ~mask;
 | |
| 	local_irq_restore(flags);
 | |
| }
 | |
| 
 | |
| #if BITS_PER_LONG == 32
 | |
| 
 | |
| static inline void atomic64_add(long long i, volatile atomic64_t *v)
 | |
| {
 | |
| 	unsigned long flags = 0;
 | |
| 
 | |
| 	local_irq_save(flags);
 | |
| 	v->counter += i;
 | |
| 	local_irq_restore(flags);
 | |
| }
 | |
| 
 | |
| static inline void atomic64_sub(long long i, volatile atomic64_t *v)
 | |
| {
 | |
| 	unsigned long flags = 0;
 | |
| 
 | |
| 	local_irq_save(flags);
 | |
| 	v->counter -= i;
 | |
| 	local_irq_restore(flags);
 | |
| }
 | |
| 
 | |
| #else /* BIT_PER_LONG == 32 */
 | |
| 
 | |
| static inline void atomic64_add(long i, volatile atomic64_t *v)
 | |
| {
 | |
| 	unsigned long flags = 0;
 | |
| 
 | |
| 	local_irq_save(flags);
 | |
| 	v->counter += i;
 | |
| 	local_irq_restore(flags);
 | |
| }
 | |
| 
 | |
| static inline void atomic64_sub(long i, volatile atomic64_t *v)
 | |
| {
 | |
| 	unsigned long flags = 0;
 | |
| 
 | |
| 	local_irq_save(flags);
 | |
| 	v->counter -= i;
 | |
| 	local_irq_restore(flags);
 | |
| }
 | |
| #endif
 | |
| 
 | |
| static inline void atomic64_inc(volatile atomic64_t *v)
 | |
| {
 | |
| 	unsigned long flags = 0;
 | |
| 
 | |
| 	local_irq_save(flags);
 | |
| 	v->counter += 1;
 | |
| 	local_irq_restore(flags);
 | |
| }
 | |
| 
 | |
| static inline void atomic64_dec(volatile atomic64_t *v)
 | |
| {
 | |
| 	unsigned long flags = 0;
 | |
| 
 | |
| 	local_irq_save(flags);
 | |
| 	v->counter -= 1;
 | |
| 	local_irq_restore(flags);
 | |
| }
 | |
| 
 | |
| /* Atomic operations are already serializing on ARM */
 | |
| #define smp_mb__before_atomic_dec()	barrier()
 | |
| #define smp_mb__after_atomic_dec()	barrier()
 | |
| #define smp_mb__before_atomic_inc()	barrier()
 | |
| #define smp_mb__after_atomic_inc()	barrier()
 | |
| 
 | |
| #endif
 | |
| #endif
 |