linux/arch/x86/include/asm/atomic64_32.h
Brian Gerst 1a3b1d89ed x86: Split atomic64_t functions into seperate headers
Split atomic64_t functions out into separate headers, since they will
not be practical to merge between 32 and 64 bits.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
LKML-Reference: <1262883215-4034-2-git-send-email-brgerst@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-01-07 11:47:31 -08:00

161 lines
3.9 KiB
C

#ifndef _ASM_X86_ATOMIC64_32_H
#define _ASM_X86_ATOMIC64_32_H
#include <linux/compiler.h>
#include <linux/types.h>
#include <asm/processor.h>
//#include <asm/cmpxchg.h>
/* An 64bit atomic type */
typedef struct {
u64 __aligned(8) counter;
} atomic64_t;
#define ATOMIC64_INIT(val) { (val) }
extern u64 atomic64_cmpxchg(atomic64_t *ptr, u64 old_val, u64 new_val);
/**
* atomic64_xchg - xchg atomic64 variable
* @ptr: pointer to type atomic64_t
* @new_val: value to assign
*
* Atomically xchgs the value of @ptr to @new_val and returns
* the old value.
*/
extern u64 atomic64_xchg(atomic64_t *ptr, u64 new_val);
/**
* atomic64_set - set atomic64 variable
* @ptr: pointer to type atomic64_t
* @new_val: value to assign
*
* Atomically sets the value of @ptr to @new_val.
*/
extern void atomic64_set(atomic64_t *ptr, u64 new_val);
/**
* atomic64_read - read atomic64 variable
* @ptr: pointer to type atomic64_t
*
* Atomically reads the value of @ptr and returns it.
*/
static inline u64 atomic64_read(atomic64_t *ptr)
{
u64 res;
/*
* Note, we inline this atomic64_t primitive because
* it only clobbers EAX/EDX and leaves the others
* untouched. We also (somewhat subtly) rely on the
* fact that cmpxchg8b returns the current 64-bit value
* of the memory location we are touching:
*/
asm volatile(
"mov %%ebx, %%eax\n\t"
"mov %%ecx, %%edx\n\t"
LOCK_PREFIX "cmpxchg8b %1\n"
: "=&A" (res)
: "m" (*ptr)
);
return res;
}
extern u64 atomic64_read(atomic64_t *ptr);
/**
* atomic64_add_return - add and return
* @delta: integer value to add
* @ptr: pointer to type atomic64_t
*
* Atomically adds @delta to @ptr and returns @delta + *@ptr
*/
extern u64 atomic64_add_return(u64 delta, atomic64_t *ptr);
/*
* Other variants with different arithmetic operators:
*/
extern u64 atomic64_sub_return(u64 delta, atomic64_t *ptr);
extern u64 atomic64_inc_return(atomic64_t *ptr);
extern u64 atomic64_dec_return(atomic64_t *ptr);
/**
* atomic64_add - add integer to atomic64 variable
* @delta: integer value to add
* @ptr: pointer to type atomic64_t
*
* Atomically adds @delta to @ptr.
*/
extern void atomic64_add(u64 delta, atomic64_t *ptr);
/**
* atomic64_sub - subtract the atomic64 variable
* @delta: integer value to subtract
* @ptr: pointer to type atomic64_t
*
* Atomically subtracts @delta from @ptr.
*/
extern void atomic64_sub(u64 delta, atomic64_t *ptr);
/**
* atomic64_sub_and_test - subtract value from variable and test result
* @delta: integer value to subtract
* @ptr: pointer to type atomic64_t
*
* Atomically subtracts @delta from @ptr and returns
* true if the result is zero, or false for all
* other cases.
*/
extern int atomic64_sub_and_test(u64 delta, atomic64_t *ptr);
/**
* atomic64_inc - increment atomic64 variable
* @ptr: pointer to type atomic64_t
*
* Atomically increments @ptr by 1.
*/
extern void atomic64_inc(atomic64_t *ptr);
/**
* atomic64_dec - decrement atomic64 variable
* @ptr: pointer to type atomic64_t
*
* Atomically decrements @ptr by 1.
*/
extern void atomic64_dec(atomic64_t *ptr);
/**
* atomic64_dec_and_test - decrement and test
* @ptr: pointer to type atomic64_t
*
* Atomically decrements @ptr by 1 and
* returns true if the result is 0, or false for all other
* cases.
*/
extern int atomic64_dec_and_test(atomic64_t *ptr);
/**
* atomic64_inc_and_test - increment and test
* @ptr: pointer to type atomic64_t
*
* Atomically increments @ptr by 1
* and returns true if the result is zero, or false for all
* other cases.
*/
extern int atomic64_inc_and_test(atomic64_t *ptr);
/**
* atomic64_add_negative - add and test if negative
* @delta: integer value to add
* @ptr: pointer to type atomic64_t
*
* Atomically adds @delta to @ptr and returns true
* if the result is negative, or false when
* result is greater than or equal to zero.
*/
extern int atomic64_add_negative(u64 delta, atomic64_t *ptr);
#endif /* _ASM_X86_ATOMIC64_32_H */