add atomic_xchg() to all the architectures. Needed by the new mutex code. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@infradead.org>
		
			
				
	
	
		
			159 lines
		
	
	
		
			3.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			159 lines
		
	
	
		
			3.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| #ifndef __ASM_SH64_ATOMIC_H
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| #define __ASM_SH64_ATOMIC_H
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| 
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| /*
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|  * This file is subject to the terms and conditions of the GNU General Public
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|  * License.  See the file "COPYING" in the main directory of this archive
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|  * for more details.
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|  *
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|  * include/asm-sh64/atomic.h
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|  *
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|  * Copyright (C) 2000, 2001  Paolo Alberelli
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|  * Copyright (C) 2003  Paul Mundt
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|  *
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|  */
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| 
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| /*
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|  * Atomic operations that C can't guarantee us.  Useful for
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|  * resource counting etc..
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|  *
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|  */
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| 
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| typedef struct { volatile int counter; } atomic_t;
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| 
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| #define ATOMIC_INIT(i)	( (atomic_t) { (i) } )
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| 
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| #define atomic_read(v)		((v)->counter)
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| #define atomic_set(v,i)		((v)->counter = (i))
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| 
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| #include <asm/system.h>
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| 
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| /*
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|  * To get proper branch prediction for the main line, we must branch
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|  * forward to code at the end of this object's .text section, then
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|  * branch back to restart the operation.
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|  */
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| 
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| static __inline__ void atomic_add(int i, atomic_t * v)
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| {
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| 	unsigned long flags;
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| 
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| 	local_irq_save(flags);
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| 	*(long *)v += i;
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| 	local_irq_restore(flags);
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| }
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| 
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| static __inline__ void atomic_sub(int i, atomic_t *v)
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| {
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| 	unsigned long flags;
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| 
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| 	local_irq_save(flags);
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| 	*(long *)v -= i;
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| 	local_irq_restore(flags);
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| }
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| 
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| static __inline__ int atomic_add_return(int i, atomic_t * v)
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| {
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| 	unsigned long temp, flags;
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| 
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| 	local_irq_save(flags);
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| 	temp = *(long *)v;
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| 	temp += i;
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| 	*(long *)v = temp;
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| 	local_irq_restore(flags);
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| 
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| 	return temp;
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| }
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| 
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| #define atomic_add_negative(a, v)	(atomic_add_return((a), (v)) < 0)
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| 
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| static __inline__ int atomic_sub_return(int i, atomic_t * v)
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| {
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| 	unsigned long temp, flags;
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| 
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| 	local_irq_save(flags);
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| 	temp = *(long *)v;
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| 	temp -= i;
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| 	*(long *)v = temp;
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| 	local_irq_restore(flags);
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| 
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| 	return temp;
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| }
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| 
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| #define atomic_dec_return(v) atomic_sub_return(1,(v))
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| #define atomic_inc_return(v) atomic_add_return(1,(v))
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| 
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| /*
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|  * atomic_inc_and_test - increment and test
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|  * @v: pointer of type atomic_t
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|  *
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|  * Atomically increments @v by 1
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|  * and returns true if the result is zero, or false for all
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|  * other cases.
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|  */
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| #define atomic_inc_and_test(v) (atomic_inc_return(v) == 0)
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| 
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| #define atomic_sub_and_test(i,v) (atomic_sub_return((i), (v)) == 0)
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| #define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0)
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| 
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| #define atomic_inc(v) atomic_add(1,(v))
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| #define atomic_dec(v) atomic_sub(1,(v))
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| 
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| static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
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| {
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| 	int ret;
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| 	unsigned long flags;
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| 
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| 	local_irq_save(flags);
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| 	ret = v->counter;
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| 	if (likely(ret == old))
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| 		v->counter = new;
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| 	local_irq_restore(flags);
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| 
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| 	return ret;
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| }
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| 
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| #define atomic_xchg(v, new) (xchg(&((v)->counter), new))
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| 
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| static inline int atomic_add_unless(atomic_t *v, int a, int u)
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| {
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| 	int ret;
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| 	unsigned long flags;
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| 
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| 	local_irq_save(flags);
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| 	ret = v->counter;
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| 	if (ret != u)
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| 		v->counter += a;
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| 	local_irq_restore(flags);
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| 
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| 	return ret != u;
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| }
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| #define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
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| 
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| static __inline__ void atomic_clear_mask(unsigned int mask, atomic_t *v)
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| {
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| 	unsigned long flags;
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| 
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| 	local_irq_save(flags);
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| 	*(long *)v &= ~mask;
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| 	local_irq_restore(flags);
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| }
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| 
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| static __inline__ void atomic_set_mask(unsigned int mask, atomic_t *v)
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| {
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| 	unsigned long flags;
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| 
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| 	local_irq_save(flags);
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| 	*(long *)v |= mask;
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| 	local_irq_restore(flags);
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| }
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| 
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| /* Atomic operations are already serializing on SH */
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| #define smp_mb__before_atomic_dec()	barrier()
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| #define smp_mb__after_atomic_dec()	barrier()
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| #define smp_mb__before_atomic_inc()	barrier()
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| #define smp_mb__after_atomic_inc()	barrier()
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| 
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| #include <asm-generic/atomic.h>
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| #endif /* __ASM_SH64_ATOMIC_H */
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