typedef struct { volatile int counter; } atomic_t;
#ifdef __KERNEL__
+#include <linux/compiler.h>
#include <asm/synch.h>
#include <asm/asm-compat.h>
PPC405_ERR77(0,%3)
" stwcx. %0,0,%3 \n\
bne- 1b"
- : "=&r" (t), "=m" (v->counter)
- : "r" (a), "r" (&v->counter), "m" (v->counter)
+ : "=&r" (t), "+m" (v->counter)
+ : "r" (a), "r" (&v->counter)
: "cc");
}
PPC405_ERR77(0,%3)
" stwcx. %0,0,%3 \n\
bne- 1b"
- : "=&r" (t), "=m" (v->counter)
- : "r" (a), "r" (&v->counter), "m" (v->counter)
+ : "=&r" (t), "+m" (v->counter)
+ : "r" (a), "r" (&v->counter)
: "cc");
}
PPC405_ERR77(0,%2)
" stwcx. %0,0,%2 \n\
bne- 1b"
- : "=&r" (t), "=m" (v->counter)
- : "r" (&v->counter), "m" (v->counter)
+ : "=&r" (t), "+m" (v->counter)
+ : "r" (&v->counter)
: "cc");
}
PPC405_ERR77(0,%2)\
" stwcx. %0,0,%2\n\
bne- 1b"
- : "=&r" (t), "=m" (v->counter)
- : "r" (&v->counter), "m" (v->counter)
+ : "=&r" (t), "+m" (v->counter)
+ : "r" (&v->counter)
: "cc");
}
* 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); \
- for (;;) { \
- if (unlikely(c == (u))) \
- break; \
- old = atomic_cmpxchg((v), c, c + (a)); \
- if (likely(old == c)) \
- break; \
- c = old; \
- } \
- c != (u); \
-})
+static __inline__ int atomic_add_unless(atomic_t *v, int a, int u)
+{
+ int t;
+
+ __asm__ __volatile__ (
+ LWSYNC_ON_SMP
+"1: lwarx %0,0,%1 # atomic_add_unless\n\
+ cmpw 0,%0,%3 \n\
+ beq- 2f \n\
+ add %0,%2,%0 \n"
+ PPC405_ERR77(0,%2)
+" stwcx. %0,0,%1 \n\
+ bne- 1b \n"
+ ISYNC_ON_SMP
+" subf %0,%2,%0 \n\
+2:"
+ : "=&r" (t)
+ : "r" (&v->counter), "r" (a), "r" (u)
+ : "cc", "memory");
+
+ return t != u;
+}
+
#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
#define atomic_sub_and_test(a, v) (atomic_sub_return((a), (v)) == 0)
/*
* Atomically test *v and decrement if it is greater than 0.
- * The function returns the old value of *v minus 1.
+ * The function returns the old value of *v minus 1, even if
+ * the atomic variable, v, was not decremented.
*/
static __inline__ int atomic_dec_if_positive(atomic_t *v)
{
__asm__ __volatile__(
LWSYNC_ON_SMP
"1: lwarx %0,0,%1 # atomic_dec_if_positive\n\
- addic. %0,%0,-1\n\
+ cmpwi %0,1\n\
+ addi %0,%0,-1\n\
blt- 2f\n"
PPC405_ERR77(0,%1)
" stwcx. %0,0,%1\n\
bne- 1b"
ISYNC_ON_SMP
"\n\
-2:" : "=&r" (t)
+2:" : "=&b" (t)
: "r" (&v->counter)
: "cc", "memory");
add %0,%2,%0\n\
stdcx. %0,0,%3 \n\
bne- 1b"
- : "=&r" (t), "=m" (v->counter)
- : "r" (a), "r" (&v->counter), "m" (v->counter)
+ : "=&r" (t), "+m" (v->counter)
+ : "r" (a), "r" (&v->counter)
: "cc");
}
subf %0,%2,%0\n\
stdcx. %0,0,%3 \n\
bne- 1b"
- : "=&r" (t), "=m" (v->counter)
- : "r" (a), "r" (&v->counter), "m" (v->counter)
+ : "=&r" (t), "+m" (v->counter)
+ : "r" (a), "r" (&v->counter)
: "cc");
}
addic %0,%0,1\n\
stdcx. %0,0,%2 \n\
bne- 1b"
- : "=&r" (t), "=m" (v->counter)
- : "r" (&v->counter), "m" (v->counter)
+ : "=&r" (t), "+m" (v->counter)
+ : "r" (&v->counter)
: "cc");
}
addic %0,%0,-1\n\
stdcx. %0,0,%2\n\
bne- 1b"
- : "=&r" (t), "=m" (v->counter)
- : "r" (&v->counter), "m" (v->counter)
+ : "=&r" (t), "+m" (v->counter)
+ : "r" (&v->counter)
: "cc");
}