kernel-fxtec-pro1x/arch/x86/include/asm/atomic_32.h
Ingo Molnar cc4949e1fd Merge branch 'linus' into x86/urgent
Merge reason: pull in latest to fix a bug in it.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-06-17 08:59:10 +02:00

486 lines
11 KiB
C

#ifndef _ASM_X86_ATOMIC_32_H
#define _ASM_X86_ATOMIC_32_H
#include <linux/compiler.h>
#include <linux/types.h>
#include <asm/processor.h>
#include <asm/cmpxchg.h>
/*
* Atomic operations that C can't guarantee us. Useful for
* resource counting etc..
*/
#define ATOMIC_INIT(i) { (i) }
/**
* atomic_read - read atomic variable
* @v: pointer of type atomic_t
*
* Atomically reads the value of @v.
*/
#define atomic_read(v) ((v)->counter)
/**
* atomic_set - set atomic variable
* @v: pointer of type atomic_t
* @i: required value
*
* Atomically sets the value of @v to @i.
*/
#define atomic_set(v, i) (((v)->counter) = (i))
/**
* atomic_add - add integer to atomic variable
* @i: integer value to add
* @v: pointer of type atomic_t
*
* Atomically adds @i to @v.
*/
static inline void atomic_add(int i, atomic_t *v)
{
asm volatile(LOCK_PREFIX "addl %1,%0"
: "+m" (v->counter)
: "ir" (i));
}
/**
* atomic_sub - subtract integer from atomic variable
* @i: integer value to subtract
* @v: pointer of type atomic_t
*
* Atomically subtracts @i from @v.
*/
static inline void atomic_sub(int i, atomic_t *v)
{
asm volatile(LOCK_PREFIX "subl %1,%0"
: "+m" (v->counter)
: "ir" (i));
}
/**
* atomic_sub_and_test - subtract value from variable and test result
* @i: integer value to subtract
* @v: pointer of type atomic_t
*
* Atomically subtracts @i from @v and returns
* true if the result is zero, or false for all
* other cases.
*/
static inline int atomic_sub_and_test(int i, atomic_t *v)
{
unsigned char c;
asm volatile(LOCK_PREFIX "subl %2,%0; sete %1"
: "+m" (v->counter), "=qm" (c)
: "ir" (i) : "memory");
return c;
}
/**
* atomic_inc - increment atomic variable
* @v: pointer of type atomic_t
*
* Atomically increments @v by 1.
*/
static inline void atomic_inc(atomic_t *v)
{
asm volatile(LOCK_PREFIX "incl %0"
: "+m" (v->counter));
}
/**
* atomic_dec - decrement atomic variable
* @v: pointer of type atomic_t
*
* Atomically decrements @v by 1.
*/
static inline void atomic_dec(atomic_t *v)
{
asm volatile(LOCK_PREFIX "decl %0"
: "+m" (v->counter));
}
/**
* atomic_dec_and_test - decrement and test
* @v: pointer of type atomic_t
*
* Atomically decrements @v by 1 and
* returns true if the result is 0, or false for all other
* cases.
*/
static inline int atomic_dec_and_test(atomic_t *v)
{
unsigned char c;
asm volatile(LOCK_PREFIX "decl %0; sete %1"
: "+m" (v->counter), "=qm" (c)
: : "memory");
return c != 0;
}
/**
* 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.
*/
static inline int atomic_inc_and_test(atomic_t *v)
{
unsigned char c;
asm volatile(LOCK_PREFIX "incl %0; sete %1"
: "+m" (v->counter), "=qm" (c)
: : "memory");
return c != 0;
}
/**
* atomic_add_negative - add and test if negative
* @v: pointer of type atomic_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.
*/
static inline int atomic_add_negative(int i, atomic_t *v)
{
unsigned char c;
asm volatile(LOCK_PREFIX "addl %2,%0; sets %1"
: "+m" (v->counter), "=qm" (c)
: "ir" (i) : "memory");
return c;
}
/**
* atomic_add_return - add integer and return
* @v: pointer of type atomic_t
* @i: integer value to add
*
* Atomically adds @i to @v and returns @i + @v
*/
static inline int atomic_add_return(int i, atomic_t *v)
{
int __i;
#ifdef CONFIG_M386
unsigned long flags;
if (unlikely(boot_cpu_data.x86 <= 3))
goto no_xadd;
#endif
/* Modern 486+ processor */
__i = i;
asm volatile(LOCK_PREFIX "xaddl %0, %1"
: "+r" (i), "+m" (v->counter)
: : "memory");
return i + __i;
#ifdef CONFIG_M386
no_xadd: /* Legacy 386 processor */
local_irq_save(flags);
__i = atomic_read(v);
atomic_set(v, i + __i);
local_irq_restore(flags);
return i + __i;
#endif
}
/**
* atomic_sub_return - subtract integer and return
* @v: pointer of type atomic_t
* @i: integer value to subtract
*
* Atomically subtracts @i from @v and returns @v - @i
*/
static inline int atomic_sub_return(int i, atomic_t *v)
{
return atomic_add_return(-i, v);
}
#define atomic_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), (old), (new)))
#define atomic_xchg(v, new) (xchg(&((v)->counter), (new)))
/**
* atomic_add_unless - add unless the number is already a given value
* @v: pointer of type atomic_t
* @a: the amount to add to v...
* @u: ...unless v is equal to u.
*
* Atomically adds @a to @v, so long as @v was not already @u.
* Returns non-zero if @v was not @u, and zero otherwise.
*/
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 != (u);
}
#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
#define atomic_inc_return(v) (atomic_add_return(1, v))
#define atomic_dec_return(v) (atomic_sub_return(1, v))
/* These are x86-specific, used by some header files */
#define atomic_clear_mask(mask, addr) \
asm volatile(LOCK_PREFIX "andl %0,%1" \
: : "r" (~(mask)), "m" (*(addr)) : "memory")
#define atomic_set_mask(mask, addr) \
asm volatile(LOCK_PREFIX "orl %0,%1" \
: : "r" (mask), "m" (*(addr)) : "memory")
/* Atomic operations are already serializing on x86 */
#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()
/* An 64bit atomic type */
typedef struct {
unsigned long long counter;
} atomic64_t;
#define ATOMIC64_INIT(val) { (val) }
/**
* atomic64_read - read atomic64 variable
* @ptr: pointer of type atomic64_t
*
* Atomically reads the value of @v.
* Doesn't imply a read memory barrier.
*/
#define __atomic64_read(ptr) ((ptr)->counter)
static inline unsigned long long
cmpxchg8b(unsigned long long *ptr, unsigned long long old, unsigned long long new)
{
asm volatile(
LOCK_PREFIX "cmpxchg8b (%[ptr])\n"
: "=A" (old)
: [ptr] "D" (ptr),
"A" (old),
"b" (ll_low(new)),
"c" (ll_high(new))
: "memory");
return old;
}
static inline unsigned long long
atomic64_cmpxchg(atomic64_t *ptr, unsigned long long old_val,
unsigned long long new_val)
{
return cmpxchg8b(&ptr->counter, old_val, 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.
*/
static inline unsigned long long
atomic64_xchg(atomic64_t *ptr, unsigned long long new_val)
{
unsigned long long old_val;
do {
old_val = atomic_read(ptr);
} while (atomic64_cmpxchg(ptr, old_val, new_val) != old_val);
return old_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.
*/
static inline void atomic64_set(atomic64_t *ptr, unsigned long long new_val)
{
atomic64_xchg(ptr, new_val);
}
/**
* atomic64_read - read atomic64 variable
* @ptr: pointer to type atomic64_t
*
* Atomically reads the value of @ptr and returns it.
*/
static inline unsigned long long atomic64_read(atomic64_t *ptr)
{
unsigned long long curr_val;
do {
curr_val = __atomic64_read(ptr);
} while (atomic64_cmpxchg(ptr, curr_val, curr_val) != curr_val);
return curr_val;
}
/**
* 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
*/
static inline unsigned long long
atomic64_add_return(unsigned long long delta, atomic64_t *ptr)
{
unsigned long long old_val, new_val;
do {
old_val = atomic_read(ptr);
new_val = old_val + delta;
} while (atomic64_cmpxchg(ptr, old_val, new_val) != old_val);
return new_val;
}
static inline long atomic64_sub_return(unsigned long long delta, atomic64_t *ptr)
{
return atomic64_add_return(-delta, ptr);
}
static inline long atomic64_inc_return(atomic64_t *ptr)
{
return atomic64_add_return(1, ptr);
}
static inline long atomic64_dec_return(atomic64_t *ptr)
{
return atomic64_sub_return(1, ptr);
}
/**
* atomic64_add - add integer to atomic64 variable
* @delta: integer value to add
* @ptr: pointer to type atomic64_t
*
* Atomically adds @delta to @ptr.
*/
static inline void atomic64_add(unsigned long long delta, atomic64_t *ptr)
{
atomic64_add_return(delta, ptr);
}
/**
* atomic64_sub - subtract the atomic64 variable
* @delta: integer value to subtract
* @ptr: pointer to type atomic64_t
*
* Atomically subtracts @delta from @ptr.
*/
static inline void atomic64_sub(unsigned long long delta, atomic64_t *ptr)
{
atomic64_add(-delta, 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.
*/
static inline int
atomic64_sub_and_test(unsigned long long delta, atomic64_t *ptr)
{
unsigned long long old_val = atomic64_sub_return(delta, ptr);
return old_val == 0;
}
/**
* atomic64_inc - increment atomic64 variable
* @ptr: pointer to type atomic64_t
*
* Atomically increments @ptr by 1.
*/
static inline void atomic64_inc(atomic64_t *ptr)
{
atomic64_add(1, ptr);
}
/**
* atomic64_dec - decrement atomic64 variable
* @ptr: pointer to type atomic64_t
*
* Atomically decrements @ptr by 1.
*/
static inline void atomic64_dec(atomic64_t *ptr)
{
atomic64_sub(1, 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.
*/
static inline int atomic64_dec_and_test(atomic64_t *ptr)
{
return atomic64_sub_and_test(1, 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.
*/
static inline int atomic64_inc_and_test(atomic64_t *ptr)
{
return atomic64_sub_and_test(-1, 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.
*/
static inline int
atomic64_add_negative(unsigned long long delta, atomic64_t *ptr)
{
long long old_val = atomic64_add_return(delta, ptr);
return old_val < 0;
}
#include <asm-generic/atomic-long.h>
#endif /* _ASM_X86_ATOMIC_32_H */