 2291059c85
			
		
	
	
	2291059c85
	
	
	
		
			
			Use the much more reader friendly ACCESS_ONCE() instead of the cast to volatile. This is purely a stylistic change. Signed-off-by: Pranith Kumar <bobby.prani@gmail.com> Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no> Acked-by: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: linux-arch@vger.kernel.org Link: http://lkml.kernel.org/r/1411482607-20948-1-git-send-email-bobby.prani@gmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
		
			
				
	
	
		
			113 lines
		
	
	
	
		
			3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			113 lines
		
	
	
	
		
			3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /* atomic.h: Thankfully the V9 is at least reasonable for this
 | |
|  *           stuff.
 | |
|  *
 | |
|  * Copyright (C) 1996, 1997, 2000, 2012 David S. Miller (davem@redhat.com)
 | |
|  */
 | |
| 
 | |
| #ifndef __ARCH_SPARC64_ATOMIC__
 | |
| #define __ARCH_SPARC64_ATOMIC__
 | |
| 
 | |
| #include <linux/types.h>
 | |
| #include <asm/cmpxchg.h>
 | |
| #include <asm/barrier.h>
 | |
| 
 | |
| #define ATOMIC_INIT(i)		{ (i) }
 | |
| #define ATOMIC64_INIT(i)	{ (i) }
 | |
| 
 | |
| #define atomic_read(v)		ACCESS_ONCE((v)->counter)
 | |
| #define atomic64_read(v)	ACCESS_ONCE((v)->counter)
 | |
| 
 | |
| #define atomic_set(v, i)	(((v)->counter) = i)
 | |
| #define atomic64_set(v, i)	(((v)->counter) = i)
 | |
| 
 | |
| #define ATOMIC_OP(op)							\
 | |
| void atomic_##op(int, atomic_t *);					\
 | |
| void atomic64_##op(long, atomic64_t *);
 | |
| 
 | |
| #define ATOMIC_OP_RETURN(op)						\
 | |
| int atomic_##op##_return(int, atomic_t *);				\
 | |
| long atomic64_##op##_return(long, atomic64_t *);
 | |
| 
 | |
| #define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op)
 | |
| 
 | |
| ATOMIC_OPS(add)
 | |
| ATOMIC_OPS(sub)
 | |
| 
 | |
| #undef ATOMIC_OPS
 | |
| #undef ATOMIC_OP_RETURN
 | |
| #undef ATOMIC_OP
 | |
| 
 | |
| #define atomic_dec_return(v)   atomic_sub_return(1, v)
 | |
| #define atomic64_dec_return(v) atomic64_sub_return(1, v)
 | |
| 
 | |
| #define atomic_inc_return(v)   atomic_add_return(1, v)
 | |
| #define atomic64_inc_return(v) atomic64_add_return(1, v)
 | |
| 
 | |
| /*
 | |
|  * atomic_inc_and_test - increment and test
 | |
|  * @v: pointer of type atomic_t
 | |
|  *
 | |
|  * Atomically increments @v by 1
 | |
|  * and returns true if the result is zero, or false for all
 | |
|  * other cases.
 | |
|  */
 | |
| #define atomic_inc_and_test(v) (atomic_inc_return(v) == 0)
 | |
| #define atomic64_inc_and_test(v) (atomic64_inc_return(v) == 0)
 | |
| 
 | |
| #define atomic_sub_and_test(i, v) (atomic_sub_return(i, v) == 0)
 | |
| #define atomic64_sub_and_test(i, v) (atomic64_sub_return(i, v) == 0)
 | |
| 
 | |
| #define atomic_dec_and_test(v) (atomic_sub_return(1, v) == 0)
 | |
| #define atomic64_dec_and_test(v) (atomic64_sub_return(1, v) == 0)
 | |
| 
 | |
| #define atomic_inc(v) atomic_add(1, v)
 | |
| #define atomic64_inc(v) atomic64_add(1, v)
 | |
| 
 | |
| #define atomic_dec(v) atomic_sub(1, v)
 | |
| #define atomic64_dec(v) atomic64_sub(1, v)
 | |
| 
 | |
| #define atomic_add_negative(i, v) (atomic_add_return(i, v) < 0)
 | |
| #define atomic64_add_negative(i, v) (atomic64_add_return(i, v) < 0)
 | |
| 
 | |
| #define atomic_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n)))
 | |
| #define atomic_xchg(v, new) (xchg(&((v)->counter), new))
 | |
| 
 | |
| static inline int __atomic_add_unless(atomic_t *v, int a, int u)
 | |
| {
 | |
| 	int c, old;
 | |
| 	c = atomic_read(v);
 | |
| 	for (;;) {
 | |
| 		if (unlikely(c == (u)))
 | |
| 			break;
 | |
| 		old = atomic_cmpxchg((v), c, c + (a));
 | |
| 		if (likely(old == c))
 | |
| 			break;
 | |
| 		c = old;
 | |
| 	}
 | |
| 	return c;
 | |
| }
 | |
| 
 | |
| #define atomic64_cmpxchg(v, o, n) \
 | |
| 	((__typeof__((v)->counter))cmpxchg(&((v)->counter), (o), (n)))
 | |
| #define atomic64_xchg(v, new) (xchg(&((v)->counter), new))
 | |
| 
 | |
| static inline long atomic64_add_unless(atomic64_t *v, long a, long u)
 | |
| {
 | |
| 	long c, old;
 | |
| 	c = atomic64_read(v);
 | |
| 	for (;;) {
 | |
| 		if (unlikely(c == (u)))
 | |
| 			break;
 | |
| 		old = atomic64_cmpxchg((v), c, c + (a));
 | |
| 		if (likely(old == c))
 | |
| 			break;
 | |
| 		c = old;
 | |
| 	}
 | |
| 	return c != (u);
 | |
| }
 | |
| 
 | |
| #define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0)
 | |
| 
 | |
| long atomic64_dec_if_positive(atomic64_t *v);
 | |
| 
 | |
| #endif /* !(__ARCH_SPARC64_ATOMIC__) */
 |