Make <asm-x86/spinlock.h> use ACCESS_ONCE()

..instead of cooking up its own uglier local version of it.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Linus Torvalds 2008-05-10 19:52:43 -07:00
parent 9c3cdc1f83
commit 39f004ba27

View file

@ -20,18 +20,8 @@
*/
#ifdef CONFIG_X86_32
typedef char _slock_t;
# define LOCK_INS_DEC "decb"
# define LOCK_INS_XCH "xchgb"
# define LOCK_INS_MOV "movb"
# define LOCK_INS_CMP "cmpb"
# define LOCK_PTR_REG "a"
#else
typedef int _slock_t;
# define LOCK_INS_DEC "decl"
# define LOCK_INS_XCH "xchgl"
# define LOCK_INS_MOV "movl"
# define LOCK_INS_CMP "cmpl"
# define LOCK_PTR_REG "D"
#endif
@ -66,14 +56,14 @@ typedef int _slock_t;
#if (NR_CPUS < 256)
static inline int __raw_spin_is_locked(raw_spinlock_t *lock)
{
int tmp = *(volatile signed int *)(&(lock)->slock);
int tmp = ACCESS_ONCE(lock->slock);
return (((tmp >> 8) & 0xff) != (tmp & 0xff));
}
static inline int __raw_spin_is_contended(raw_spinlock_t *lock)
{
int tmp = *(volatile signed int *)(&(lock)->slock);
int tmp = ACCESS_ONCE(lock->slock);
return (((tmp >> 8) & 0xff) - (tmp & 0xff)) > 1;
}
@ -130,14 +120,14 @@ static __always_inline void __raw_spin_unlock(raw_spinlock_t *lock)
#else
static inline int __raw_spin_is_locked(raw_spinlock_t *lock)
{
int tmp = *(volatile signed int *)(&(lock)->slock);
int tmp = ACCESS_ONCE(lock->slock);
return (((tmp >> 16) & 0xffff) != (tmp & 0xffff));
}
static inline int __raw_spin_is_contended(raw_spinlock_t *lock)
{
int tmp = *(volatile signed int *)(&(lock)->slock);
int tmp = ACCESS_ONCE(lock->slock);
return (((tmp >> 16) & 0xffff) - (tmp & 0xffff)) > 1;
}