 0038df2240
			
		
	
	
	0038df2240
	
	
	
		
			
			MIPS R6 changed the opcodes for LL/SC instructions so we need to set the correct ISA level. Cc: Matthew Fortune <Matthew.Fortune@imgtec.com> Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
		
			
				
	
	
		
			591 lines
		
	
	
	
		
			16 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			591 lines
		
	
	
	
		
			16 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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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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|  * But use these as seldom as possible since they are much more slower
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|  * than regular operations.
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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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|  * Copyright (C) 1996, 97, 99, 2000, 03, 04, 06 by Ralf Baechle
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|  */
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| #ifndef _ASM_ATOMIC_H
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| #define _ASM_ATOMIC_H
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| 
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| #include <linux/irqflags.h>
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| #include <linux/types.h>
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| #include <asm/barrier.h>
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| #include <asm/compiler.h>
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| #include <asm/cpu-features.h>
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| #include <asm/cmpxchg.h>
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| #include <asm/war.h>
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| 
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| #define ATOMIC_INIT(i)	  { (i) }
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| 
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| /*
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|  * atomic_read - read atomic variable
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|  * @v: pointer of type atomic_t
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|  *
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|  * Atomically reads the value of @v.
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|  */
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| #define atomic_read(v)		ACCESS_ONCE((v)->counter)
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| 
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| /*
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|  * atomic_set - set atomic variable
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|  * @v: pointer of type atomic_t
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|  * @i: required value
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|  *
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|  * Atomically sets the value of @v to @i.
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|  */
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| #define atomic_set(v, i)		((v)->counter = (i))
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| 
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| #define ATOMIC_OP(op, c_op, asm_op)					      \
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| static __inline__ void atomic_##op(int i, atomic_t * v)			      \
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| {									      \
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| 	if (kernel_uses_llsc && R10000_LLSC_WAR) {			      \
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| 		int temp;						      \
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| 									      \
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| 		__asm__ __volatile__(					      \
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| 		"	.set	arch=r4000				\n"   \
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| 		"1:	ll	%0, %1		# atomic_" #op "	\n"   \
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| 		"	" #asm_op " %0, %2				\n"   \
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| 		"	sc	%0, %1					\n"   \
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| 		"	beqzl	%0, 1b					\n"   \
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| 		"	.set	mips0					\n"   \
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| 		: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter)	      \
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| 		: "Ir" (i));						      \
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| 	} else if (kernel_uses_llsc) {					      \
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| 		int temp;						      \
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| 									      \
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| 		do {							      \
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| 			__asm__ __volatile__(				      \
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| 			"	.set	"MIPS_ISA_LEVEL"		\n"   \
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| 			"	ll	%0, %1		# atomic_" #op "\n"   \
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| 			"	" #asm_op " %0, %2			\n"   \
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| 			"	sc	%0, %1				\n"   \
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| 			"	.set	mips0				\n"   \
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| 			: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter)      \
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| 			: "Ir" (i));					      \
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| 		} while (unlikely(!temp));				      \
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| 	} else {							      \
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| 		unsigned long flags;					      \
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| 									      \
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| 		raw_local_irq_save(flags);				      \
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| 		v->counter c_op i;					      \
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| 		raw_local_irq_restore(flags);				      \
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| 	}								      \
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| }
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| 
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| #define ATOMIC_OP_RETURN(op, c_op, asm_op)				      \
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| static __inline__ int atomic_##op##_return(int i, atomic_t * v)		      \
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| {									      \
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| 	int result;							      \
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| 									      \
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| 	smp_mb__before_llsc();						      \
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| 									      \
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| 	if (kernel_uses_llsc && R10000_LLSC_WAR) {			      \
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| 		int temp;						      \
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| 									      \
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| 		__asm__ __volatile__(					      \
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| 		"	.set	arch=r4000				\n"   \
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| 		"1:	ll	%1, %2		# atomic_" #op "_return	\n"   \
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| 		"	" #asm_op " %0, %1, %3				\n"   \
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| 		"	sc	%0, %2					\n"   \
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| 		"	beqzl	%0, 1b					\n"   \
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| 		"	" #asm_op " %0, %1, %3				\n"   \
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| 		"	.set	mips0					\n"   \
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| 		: "=&r" (result), "=&r" (temp),				      \
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| 		  "+" GCC_OFF_SMALL_ASM() (v->counter)			      \
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| 		: "Ir" (i));						      \
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| 	} else if (kernel_uses_llsc) {					      \
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| 		int temp;						      \
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| 									      \
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| 		do {							      \
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| 			__asm__ __volatile__(				      \
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| 			"	.set	"MIPS_ISA_LEVEL"		\n"   \
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| 			"	ll	%1, %2	# atomic_" #op "_return	\n"   \
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| 			"	" #asm_op " %0, %1, %3			\n"   \
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| 			"	sc	%0, %2				\n"   \
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| 			"	.set	mips0				\n"   \
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| 			: "=&r" (result), "=&r" (temp),			      \
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| 			  "+" GCC_OFF_SMALL_ASM() (v->counter)		      \
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| 			: "Ir" (i));					      \
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| 		} while (unlikely(!result));				      \
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| 									      \
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| 		result = temp; result c_op i;				      \
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| 	} else {							      \
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| 		unsigned long flags;					      \
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| 									      \
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| 		raw_local_irq_save(flags);				      \
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| 		result = v->counter;					      \
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| 		result c_op i;						      \
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| 		v->counter = result;					      \
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| 		raw_local_irq_restore(flags);				      \
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| 	}								      \
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| 									      \
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| 	smp_llsc_mb();							      \
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| 									      \
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| 	return result;							      \
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| }
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| 
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| #define ATOMIC_OPS(op, c_op, asm_op)					      \
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| 	ATOMIC_OP(op, c_op, asm_op)					      \
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| 	ATOMIC_OP_RETURN(op, c_op, asm_op)
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| 
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| ATOMIC_OPS(add, +=, addu)
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| ATOMIC_OPS(sub, -=, subu)
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| 
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| #undef ATOMIC_OPS
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| #undef ATOMIC_OP_RETURN
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| #undef ATOMIC_OP
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| 
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| /*
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|  * atomic_sub_if_positive - conditionally subtract integer from atomic variable
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|  * @i: integer value to subtract
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|  * @v: pointer of type atomic_t
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|  *
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|  * Atomically test @v and subtract @i if @v is greater or equal than @i.
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|  * The function returns the old value of @v minus @i.
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|  */
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| static __inline__ int atomic_sub_if_positive(int i, atomic_t * v)
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| {
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| 	int result;
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| 
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| 	smp_mb__before_llsc();
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| 
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| 	if (kernel_uses_llsc && R10000_LLSC_WAR) {
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| 		int temp;
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| 
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| 		__asm__ __volatile__(
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| 		"	.set	arch=r4000				\n"
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| 		"1:	ll	%1, %2		# atomic_sub_if_positive\n"
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| 		"	subu	%0, %1, %3				\n"
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| 		"	bltz	%0, 1f					\n"
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| 		"	sc	%0, %2					\n"
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| 		"	.set	noreorder				\n"
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| 		"	beqzl	%0, 1b					\n"
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| 		"	 subu	%0, %1, %3				\n"
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| 		"	.set	reorder					\n"
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| 		"1:							\n"
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| 		"	.set	mips0					\n"
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| 		: "=&r" (result), "=&r" (temp),
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| 		  "+" GCC_OFF_SMALL_ASM() (v->counter)
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| 		: "Ir" (i), GCC_OFF_SMALL_ASM() (v->counter)
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| 		: "memory");
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| 	} else if (kernel_uses_llsc) {
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| 		int temp;
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| 
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| 		__asm__ __volatile__(
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| 		"	.set	"MIPS_ISA_LEVEL"			\n"
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| 		"1:	ll	%1, %2		# atomic_sub_if_positive\n"
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| 		"	subu	%0, %1, %3				\n"
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| 		"	bltz	%0, 1f					\n"
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| 		"	sc	%0, %2					\n"
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| 		"	.set	noreorder				\n"
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| 		"	beqz	%0, 1b					\n"
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| 		"	 subu	%0, %1, %3				\n"
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| 		"	.set	reorder					\n"
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| 		"1:							\n"
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| 		"	.set	mips0					\n"
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| 		: "=&r" (result), "=&r" (temp),
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| 		  "+" GCC_OFF_SMALL_ASM() (v->counter)
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| 		: "Ir" (i));
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| 	} else {
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| 		unsigned long flags;
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| 
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| 		raw_local_irq_save(flags);
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| 		result = v->counter;
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| 		result -= i;
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| 		if (result >= 0)
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| 			v->counter = result;
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| 		raw_local_irq_restore(flags);
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| 	}
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| 
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| 	smp_llsc_mb();
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| 
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| 	return result;
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| }
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| 
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| #define atomic_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n)))
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| #define atomic_xchg(v, new) (xchg(&((v)->counter), (new)))
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| 
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| /**
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|  * __atomic_add_unless - add unless the number is a given value
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|  * @v: pointer of type atomic_t
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|  * @a: the amount to add to v...
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|  * @u: ...unless v is equal to u.
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|  *
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|  * Atomically adds @a to @v, so long as it was not @u.
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|  * Returns the old value of @v.
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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 c, old;
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| 	c = atomic_read(v);
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| 	for (;;) {
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| 		if (unlikely(c == (u)))
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| 			break;
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| 		old = atomic_cmpxchg((v), c, c + (a));
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| 		if (likely(old == c))
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| 			break;
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| 		c = old;
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| 	}
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| 	return c;
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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_sub_and_test - subtract value from variable and test result
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|  * @i: integer value to subtract
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|  * @v: pointer of type atomic_t
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|  *
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|  * Atomically subtracts @i from @v and returns
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|  * 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_sub_and_test(i, v) (atomic_sub_return((i), (v)) == 0)
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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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| /*
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|  * atomic_dec_and_test - decrement by 1 and test
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|  * @v: pointer of type atomic_t
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|  *
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|  * Atomically decrements @v by 1 and
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|  * returns true if the result is 0, or false for all other
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|  * cases.
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|  */
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| #define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0)
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| 
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| /*
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|  * atomic_dec_if_positive - decrement by 1 if old value positive
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|  * @v: pointer of type atomic_t
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|  */
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| #define atomic_dec_if_positive(v)	atomic_sub_if_positive(1, v)
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| 
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| /*
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|  * atomic_inc - increment atomic variable
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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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|  */
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| #define atomic_inc(v) atomic_add(1, (v))
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| 
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| /*
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|  * atomic_dec - decrement and test
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|  * @v: pointer of type atomic_t
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|  *
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|  * Atomically decrements @v by 1.
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|  */
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| #define atomic_dec(v) atomic_sub(1, (v))
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| 
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| /*
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|  * atomic_add_negative - add and test if negative
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|  * @v: pointer of type atomic_t
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|  * @i: integer value to add
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|  *
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|  * Atomically adds @i to @v and returns true
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|  * if the result is negative, or false when
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|  * result is greater than or equal to zero.
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|  */
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| #define atomic_add_negative(i, v) (atomic_add_return(i, (v)) < 0)
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| 
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| #ifdef CONFIG_64BIT
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| 
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| #define ATOMIC64_INIT(i)    { (i) }
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| 
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| /*
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|  * atomic64_read - read atomic variable
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|  * @v: pointer of type atomic64_t
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|  *
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|  */
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| #define atomic64_read(v)	ACCESS_ONCE((v)->counter)
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| 
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| /*
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|  * atomic64_set - set atomic variable
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|  * @v: pointer of type atomic64_t
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|  * @i: required value
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|  */
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| #define atomic64_set(v, i)	((v)->counter = (i))
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| 
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| #define ATOMIC64_OP(op, c_op, asm_op)					      \
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| static __inline__ void atomic64_##op(long i, atomic64_t * v)		      \
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| {									      \
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| 	if (kernel_uses_llsc && R10000_LLSC_WAR) {			      \
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| 		long temp;						      \
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| 									      \
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| 		__asm__ __volatile__(					      \
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| 		"	.set	arch=r4000				\n"   \
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| 		"1:	lld	%0, %1		# atomic64_" #op "	\n"   \
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| 		"	" #asm_op " %0, %2				\n"   \
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| 		"	scd	%0, %1					\n"   \
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| 		"	beqzl	%0, 1b					\n"   \
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| 		"	.set	mips0					\n"   \
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| 		: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter)	      \
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| 		: "Ir" (i));						      \
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| 	} else if (kernel_uses_llsc) {					      \
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| 		long temp;						      \
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| 									      \
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| 		do {							      \
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| 			__asm__ __volatile__(				      \
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| 			"	.set	"MIPS_ISA_LEVEL"		\n"   \
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| 			"	lld	%0, %1		# atomic64_" #op "\n" \
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| 			"	" #asm_op " %0, %2			\n"   \
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| 			"	scd	%0, %1				\n"   \
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| 			"	.set	mips0				\n"   \
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| 			: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter)      \
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| 			: "Ir" (i));					      \
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| 		} while (unlikely(!temp));				      \
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| 	} else {							      \
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| 		unsigned long flags;					      \
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| 									      \
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| 		raw_local_irq_save(flags);				      \
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| 		v->counter c_op i;					      \
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| 		raw_local_irq_restore(flags);				      \
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| 	}								      \
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| }
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| 
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| #define ATOMIC64_OP_RETURN(op, c_op, asm_op)				      \
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| static __inline__ long atomic64_##op##_return(long i, atomic64_t * v)	      \
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| {									      \
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| 	long result;							      \
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| 									      \
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| 	smp_mb__before_llsc();						      \
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| 									      \
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| 	if (kernel_uses_llsc && R10000_LLSC_WAR) {			      \
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| 		long temp;						      \
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| 									      \
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| 		__asm__ __volatile__(					      \
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| 		"	.set	arch=r4000				\n"   \
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| 		"1:	lld	%1, %2		# atomic64_" #op "_return\n"  \
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| 		"	" #asm_op " %0, %1, %3				\n"   \
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| 		"	scd	%0, %2					\n"   \
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| 		"	beqzl	%0, 1b					\n"   \
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| 		"	" #asm_op " %0, %1, %3				\n"   \
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| 		"	.set	mips0					\n"   \
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| 		: "=&r" (result), "=&r" (temp),				      \
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| 		  "+" GCC_OFF_SMALL_ASM() (v->counter)			      \
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| 		: "Ir" (i));						      \
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| 	} else if (kernel_uses_llsc) {					      \
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| 		long temp;						      \
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| 									      \
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| 		do {							      \
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| 			__asm__ __volatile__(				      \
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| 			"	.set	"MIPS_ISA_LEVEL"		\n"   \
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| 			"	lld	%1, %2	# atomic64_" #op "_return\n"  \
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| 			"	" #asm_op " %0, %1, %3			\n"   \
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| 			"	scd	%0, %2				\n"   \
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| 			"	.set	mips0				\n"   \
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| 			: "=&r" (result), "=&r" (temp),			      \
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| 			  "=" GCC_OFF_SMALL_ASM() (v->counter)		      \
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| 			: "Ir" (i), GCC_OFF_SMALL_ASM() (v->counter)	      \
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| 			: "memory");					      \
 | |
| 		} while (unlikely(!result));				      \
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| 									      \
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| 		result = temp; result c_op i;				      \
 | |
| 	} else {							      \
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| 		unsigned long flags;					      \
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| 									      \
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| 		raw_local_irq_save(flags);				      \
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| 		result = v->counter;					      \
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| 		result c_op i;						      \
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| 		v->counter = result;					      \
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| 		raw_local_irq_restore(flags);				      \
 | |
| 	}								      \
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| 									      \
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| 	smp_llsc_mb();							      \
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| 									      \
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| 	return result;							      \
 | |
| }
 | |
| 
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| #define ATOMIC64_OPS(op, c_op, asm_op)					      \
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| 	ATOMIC64_OP(op, c_op, asm_op)					      \
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| 	ATOMIC64_OP_RETURN(op, c_op, asm_op)
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| 
 | |
| ATOMIC64_OPS(add, +=, daddu)
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| ATOMIC64_OPS(sub, -=, dsubu)
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| 
 | |
| #undef ATOMIC64_OPS
 | |
| #undef ATOMIC64_OP_RETURN
 | |
| #undef ATOMIC64_OP
 | |
| 
 | |
| /*
 | |
|  * atomic64_sub_if_positive - conditionally subtract integer from atomic
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|  *                            variable
 | |
|  * @i: integer value to subtract
 | |
|  * @v: pointer of type atomic64_t
 | |
|  *
 | |
|  * Atomically test @v and subtract @i if @v is greater or equal than @i.
 | |
|  * The function returns the old value of @v minus @i.
 | |
|  */
 | |
| static __inline__ long atomic64_sub_if_positive(long i, atomic64_t * v)
 | |
| {
 | |
| 	long result;
 | |
| 
 | |
| 	smp_mb__before_llsc();
 | |
| 
 | |
| 	if (kernel_uses_llsc && R10000_LLSC_WAR) {
 | |
| 		long temp;
 | |
| 
 | |
| 		__asm__ __volatile__(
 | |
| 		"	.set	arch=r4000				\n"
 | |
| 		"1:	lld	%1, %2		# atomic64_sub_if_positive\n"
 | |
| 		"	dsubu	%0, %1, %3				\n"
 | |
| 		"	bltz	%0, 1f					\n"
 | |
| 		"	scd	%0, %2					\n"
 | |
| 		"	.set	noreorder				\n"
 | |
| 		"	beqzl	%0, 1b					\n"
 | |
| 		"	 dsubu	%0, %1, %3				\n"
 | |
| 		"	.set	reorder					\n"
 | |
| 		"1:							\n"
 | |
| 		"	.set	mips0					\n"
 | |
| 		: "=&r" (result), "=&r" (temp),
 | |
| 		  "=" GCC_OFF_SMALL_ASM() (v->counter)
 | |
| 		: "Ir" (i), GCC_OFF_SMALL_ASM() (v->counter)
 | |
| 		: "memory");
 | |
| 	} else if (kernel_uses_llsc) {
 | |
| 		long temp;
 | |
| 
 | |
| 		__asm__ __volatile__(
 | |
| 		"	.set	"MIPS_ISA_LEVEL"			\n"
 | |
| 		"1:	lld	%1, %2		# atomic64_sub_if_positive\n"
 | |
| 		"	dsubu	%0, %1, %3				\n"
 | |
| 		"	bltz	%0, 1f					\n"
 | |
| 		"	scd	%0, %2					\n"
 | |
| 		"	.set	noreorder				\n"
 | |
| 		"	beqz	%0, 1b					\n"
 | |
| 		"	 dsubu	%0, %1, %3				\n"
 | |
| 		"	.set	reorder					\n"
 | |
| 		"1:							\n"
 | |
| 		"	.set	mips0					\n"
 | |
| 		: "=&r" (result), "=&r" (temp),
 | |
| 		  "+" GCC_OFF_SMALL_ASM() (v->counter)
 | |
| 		: "Ir" (i));
 | |
| 	} else {
 | |
| 		unsigned long flags;
 | |
| 
 | |
| 		raw_local_irq_save(flags);
 | |
| 		result = v->counter;
 | |
| 		result -= i;
 | |
| 		if (result >= 0)
 | |
| 			v->counter = result;
 | |
| 		raw_local_irq_restore(flags);
 | |
| 	}
 | |
| 
 | |
| 	smp_llsc_mb();
 | |
| 
 | |
| 	return result;
 | |
| }
 | |
| 
 | |
| #define atomic64_cmpxchg(v, o, n) \
 | |
| 	((__typeof__((v)->counter))cmpxchg(&((v)->counter), (o), (n)))
 | |
| #define atomic64_xchg(v, new) (xchg(&((v)->counter), (new)))
 | |
| 
 | |
| /**
 | |
|  * atomic64_add_unless - add unless the number is a given value
 | |
|  * @v: pointer of type atomic64_t
 | |
|  * @a: the amount to add to v...
 | |
|  * @u: ...unless v is equal to u.
 | |
|  *
 | |
|  * Atomically adds @a to @v, so long as it was not @u.
 | |
|  * Returns the old value of @v.
 | |
|  */
 | |
| static __inline__ int 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)
 | |
| 
 | |
| #define atomic64_dec_return(v) atomic64_sub_return(1, (v))
 | |
| #define atomic64_inc_return(v) atomic64_add_return(1, (v))
 | |
| 
 | |
| /*
 | |
|  * atomic64_sub_and_test - subtract value from variable and test result
 | |
|  * @i: integer value to subtract
 | |
|  * @v: pointer of type atomic64_t
 | |
|  *
 | |
|  * Atomically subtracts @i from @v and returns
 | |
|  * true if the result is zero, or false for all
 | |
|  * other cases.
 | |
|  */
 | |
| #define atomic64_sub_and_test(i, v) (atomic64_sub_return((i), (v)) == 0)
 | |
| 
 | |
| /*
 | |
|  * atomic64_inc_and_test - increment and test
 | |
|  * @v: pointer of type atomic64_t
 | |
|  *
 | |
|  * Atomically increments @v by 1
 | |
|  * and returns true if the result is zero, or false for all
 | |
|  * other cases.
 | |
|  */
 | |
| #define atomic64_inc_and_test(v) (atomic64_inc_return(v) == 0)
 | |
| 
 | |
| /*
 | |
|  * atomic64_dec_and_test - decrement by 1 and test
 | |
|  * @v: pointer of type atomic64_t
 | |
|  *
 | |
|  * Atomically decrements @v by 1 and
 | |
|  * returns true if the result is 0, or false for all other
 | |
|  * cases.
 | |
|  */
 | |
| #define atomic64_dec_and_test(v) (atomic64_sub_return(1, (v)) == 0)
 | |
| 
 | |
| /*
 | |
|  * atomic64_dec_if_positive - decrement by 1 if old value positive
 | |
|  * @v: pointer of type atomic64_t
 | |
|  */
 | |
| #define atomic64_dec_if_positive(v)	atomic64_sub_if_positive(1, v)
 | |
| 
 | |
| /*
 | |
|  * atomic64_inc - increment atomic variable
 | |
|  * @v: pointer of type atomic64_t
 | |
|  *
 | |
|  * Atomically increments @v by 1.
 | |
|  */
 | |
| #define atomic64_inc(v) atomic64_add(1, (v))
 | |
| 
 | |
| /*
 | |
|  * atomic64_dec - decrement and test
 | |
|  * @v: pointer of type atomic64_t
 | |
|  *
 | |
|  * Atomically decrements @v by 1.
 | |
|  */
 | |
| #define atomic64_dec(v) atomic64_sub(1, (v))
 | |
| 
 | |
| /*
 | |
|  * atomic64_add_negative - add and test if negative
 | |
|  * @v: pointer of type atomic64_t
 | |
|  * @i: integer value to add
 | |
|  *
 | |
|  * Atomically adds @i to @v and returns true
 | |
|  * if the result is negative, or false when
 | |
|  * result is greater than or equal to zero.
 | |
|  */
 | |
| #define atomic64_add_negative(i, v) (atomic64_add_return(i, (v)) < 0)
 | |
| 
 | |
| #endif /* CONFIG_64BIT */
 | |
| 
 | |
| #endif /* _ASM_ATOMIC_H */
 |