}
#ifdef CONFIG_RMW_INSNS
+
static inline int atomic_add_return(int i, atomic_t *v)
{
int t, tmp;
: "g" (i), "2" (atomic_read(v)));
return t;
}
+
+#define atomic_cmpxchg(v, o, n) ((int)cmpxchg(&((v)->counter), (o), (n)))
+#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
+
#else /* !CONFIG_RMW_INSNS */
+
static inline int atomic_add_return(int i, atomic_t * v)
{
unsigned long flags;
return t;
}
+
+static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
+{
+ unsigned long flags;
+ int prev;
+
+ local_irq_save(flags);
+ prev = atomic_read(v);
+ if (prev == old)
+ atomic_set(v, new);
+ local_irq_restore(flags);
+ return prev;
+}
+
+static inline int atomic_xchg(atomic_t *v, int new)
+{
+ unsigned long flags;
+ int prev;
+
+ local_irq_save(flags);
+ prev = atomic_read(v);
+ atomic_set(v, new);
+ local_irq_restore(flags);
+ return prev;
+}
+
#endif /* !CONFIG_RMW_INSNS */
#define atomic_dec_return(v) atomic_sub_return(1, (v))
__asm__ __volatile__("orl %1,%0" : "+m" (*v) : "id" (mask));
}
-#define atomic_cmpxchg(v, o, n) ((int)cmpxchg(&((v)->counter), (o), (n)))
-#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
-
#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) \
+ for (;;) { \
+ if (unlikely(c == (u))) \
+ break; \
+ old = atomic_cmpxchg((v), c, c + (a)); \
+ if (likely(old == c)) \
+ break; \
c = old; \
+ } \
c != (u); \
})
#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)