kernel-ark/include/asm-x86_64/atomic.h
Alan Cox 715b49ef2d [PATCH] EDAC: atomic scrub operations
EDAC requires a way to scrub memory if an ECC error is found and the chipset
does not do the work automatically.  That means rewriting memory locations
atomically with respect to all CPUs _and_ bus masters.  That means we can't
use atomic_add(foo, 0) as it gets optimised for non-SMP

This adds a function to include/asm-foo/atomic.h for the platforms currently
supported which implements a scrub of a mapped block.

It also adjusts a few other files include order where atomic.h is included
before types.h as this now causes an error as atomic_scrub uses u32.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-18 19:20:30 -08:00

443 lines
9.9 KiB
C

#ifndef __ARCH_X86_64_ATOMIC__
#define __ARCH_X86_64_ATOMIC__
#include <linux/config.h>
#include <asm/types.h>
/* atomic_t should be 32 bit signed type */
/*
* Atomic operations that C can't guarantee us. Useful for
* resource counting etc..
*/
#ifdef CONFIG_SMP
#define LOCK "lock ; "
#else
#define LOCK ""
#endif
/*
* Make sure gcc doesn't try to be clever and move things around
* on us. We need to use _exactly_ the address the user gave us,
* not some alias that contains the same information.
*/
typedef struct { volatile int counter; } atomic_t;
#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 "addl %1,%0"
:"=m" (v->counter)
:"ir" (i), "m" (v->counter));
}
/**
* atomic_sub - subtract the 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 "subl %1,%0"
:"=m" (v->counter)
:"ir" (i), "m" (v->counter));
}
/**
* 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 "subl %2,%0; sete %1"
:"=m" (v->counter), "=qm" (c)
:"ir" (i), "m" (v->counter) : "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 "incl %0"
:"=m" (v->counter)
:"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 "decl %0"
:"=m" (v->counter)
:"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 "decl %0; sete %1"
:"=m" (v->counter), "=qm" (c)
:"m" (v->counter) : "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 "incl %0; sete %1"
:"=m" (v->counter), "=qm" (c)
:"m" (v->counter) : "memory");
return c != 0;
}
/**
* atomic_add_negative - add and test if negative
* @i: integer value to add
* @v: pointer of type atomic_t
*
* 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 "addl %2,%0; sets %1"
:"=m" (v->counter), "=qm" (c)
:"ir" (i), "m" (v->counter) : "memory");
return c;
}
/**
* atomic_add_return - add and return
* @i: integer value to add
* @v: pointer of type atomic_t
*
* Atomically adds @i to @v and returns @i + @v
*/
static __inline__ int atomic_add_return(int i, atomic_t *v)
{
int __i = i;
__asm__ __volatile__(
LOCK "xaddl %0, %1;"
:"=r"(i)
:"m"(v->counter), "0"(i));
return i + __i;
}
static __inline__ int atomic_sub_return(int i, atomic_t *v)
{
return atomic_add_return(-i,v);
}
#define atomic_inc_return(v) (atomic_add_return(1,v))
#define atomic_dec_return(v) (atomic_sub_return(1,v))
/* An 64bit atomic type */
typedef struct { volatile long counter; } atomic64_t;
#define ATOMIC64_INIT(i) { (i) }
/**
* atomic64_read - read atomic64 variable
* @v: pointer of type atomic64_t
*
* Atomically reads the value of @v.
* Doesn't imply a read memory barrier.
*/
#define atomic64_read(v) ((v)->counter)
/**
* atomic64_set - set atomic64 variable
* @v: pointer to type atomic64_t
* @i: required value
*
* Atomically sets the value of @v to @i.
*/
#define atomic64_set(v,i) (((v)->counter) = (i))
/**
* atomic64_add - add integer to atomic64 variable
* @i: integer value to add
* @v: pointer to type atomic64_t
*
* Atomically adds @i to @v.
*/
static __inline__ void atomic64_add(long i, atomic64_t *v)
{
__asm__ __volatile__(
LOCK "addq %1,%0"
:"=m" (v->counter)
:"ir" (i), "m" (v->counter));
}
/**
* atomic64_sub - subtract the atomic64 variable
* @i: integer value to subtract
* @v: pointer to type atomic64_t
*
* Atomically subtracts @i from @v.
*/
static __inline__ void atomic64_sub(long i, atomic64_t *v)
{
__asm__ __volatile__(
LOCK "subq %1,%0"
:"=m" (v->counter)
:"ir" (i), "m" (v->counter));
}
/**
* atomic64_sub_and_test - subtract value from variable and test result
* @i: integer value to subtract
* @v: pointer to type atomic64_t
*
* Atomically subtracts @i from @v and returns
* true if the result is zero, or false for all
* other cases.
*/
static __inline__ int atomic64_sub_and_test(long i, atomic64_t *v)
{
unsigned char c;
__asm__ __volatile__(
LOCK "subq %2,%0; sete %1"
:"=m" (v->counter), "=qm" (c)
:"ir" (i), "m" (v->counter) : "memory");
return c;
}
/**
* atomic64_inc - increment atomic64 variable
* @v: pointer to type atomic64_t
*
* Atomically increments @v by 1.
*/
static __inline__ void atomic64_inc(atomic64_t *v)
{
__asm__ __volatile__(
LOCK "incq %0"
:"=m" (v->counter)
:"m" (v->counter));
}
/**
* atomic64_dec - decrement atomic64 variable
* @v: pointer to type atomic64_t
*
* Atomically decrements @v by 1.
*/
static __inline__ void atomic64_dec(atomic64_t *v)
{
__asm__ __volatile__(
LOCK "decq %0"
:"=m" (v->counter)
:"m" (v->counter));
}
/**
* atomic64_dec_and_test - decrement and test
* @v: pointer to type atomic64_t
*
* Atomically decrements @v 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 *v)
{
unsigned char c;
__asm__ __volatile__(
LOCK "decq %0; sete %1"
:"=m" (v->counter), "=qm" (c)
:"m" (v->counter) : "memory");
return c != 0;
}
/**
* atomic64_inc_and_test - increment and test
* @v: pointer to type atomic64_t
*
* Atomically increments @v 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 *v)
{
unsigned char c;
__asm__ __volatile__(
LOCK "incq %0; sete %1"
:"=m" (v->counter), "=qm" (c)
:"m" (v->counter) : "memory");
return c != 0;
}
/**
* atomic64_add_negative - add and test if negative
* @i: integer value to add
* @v: pointer to type atomic64_t
*
* 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 atomic64_add_negative(long i, atomic64_t *v)
{
unsigned char c;
__asm__ __volatile__(
LOCK "addq %2,%0; sets %1"
:"=m" (v->counter), "=qm" (c)
:"ir" (i), "m" (v->counter) : "memory");
return c;
}
/**
* atomic64_add_return - add and return
* @i: integer value to add
* @v: pointer to type atomic64_t
*
* Atomically adds @i to @v and returns @i + @v
*/
static __inline__ long atomic64_add_return(long i, atomic64_t *v)
{
long __i = i;
__asm__ __volatile__(
LOCK "xaddq %0, %1;"
:"=r"(i)
:"m"(v->counter), "0"(i));
return i + __i;
}
static __inline__ long atomic64_sub_return(long i, atomic64_t *v)
{
return atomic64_add_return(-i,v);
}
#define atomic64_inc_return(v) (atomic64_add_return(1,v))
#define atomic64_dec_return(v) (atomic64_sub_return(1,v))
#define atomic_cmpxchg(v, old, new) ((int)cmpxchg(&((v)->counter), old, new))
#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
/**
* atomic_add_unless - add unless the number is 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 it was not @u.
* Returns non-zero if @v was not @u, and zero otherwise.
*/
#define atomic_add_unless(v, a, u) \
({ \
int c, old; \
c = atomic_read(v); \
while (c != (u) && (old = atomic_cmpxchg((v), c, c + (a))) != c) \
c = old; \
c != (u); \
})
#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
/* These are x86-specific, used by some header files */
#define atomic_clear_mask(mask, addr) \
__asm__ __volatile__(LOCK "andl %0,%1" \
: : "r" (~(mask)),"m" (*addr) : "memory")
#define atomic_set_mask(mask, addr) \
__asm__ __volatile__(LOCK "orl %0,%1" \
: : "r" ((unsigned)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()
/* ECC atomic, DMA, SMP and interrupt safe scrub function */
static __inline__ void atomic_scrub(u32 *virt_addr, u32 size)
{
u32 i;
for (i = 0; i < size / 4; i++, virt_addr++)
/* Very carefully read and write to memory atomically
* so we are interrupt, DMA and SMP safe.
*/
__asm__ __volatile__("lock; addl $0, %0"::"m"(*virt_addr));
}
#include <asm-generic/atomic.h>
#endif