fedora core 6 1.2949 + vserver 2.2.0

[linux-2.6.git] / include / asm-powerpc / atomic.h

diff --git a/include/asm-powerpc/atomic.h b/include/asm-powerpc/atomic.h
index 147a38d..f038e33 100644 (file)
--- a/include/asm-powerpc/atomic.h
+++ b/include/asm-powerpc/atomic.h
@@ -8,6 +8,7 @@
 typedef struct { volatile int counter; } atomic_t;
 
 #ifdef __KERNEL__
+#include <linux/compiler.h>
 #include <asm/synch.h>
 #include <asm/asm-compat.h>
 
@@ -26,8 +27,8 @@ static __inline__ void atomic_add(int a, atomic_t *v)
        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");
 }
 
@@ -62,8 +63,8 @@ static __inline__ void atomic_sub(int a, atomic_t *v)
        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");
 }
 
@@ -96,8 +97,8 @@ static __inline__ void atomic_inc(atomic_t *v)
        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");
 }
 
@@ -140,8 +141,8 @@ static __inline__ void atomic_dec(atomic_t *v)
        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");
 }
 
@@ -176,20 +177,29 @@ static __inline__ int atomic_dec_return(atomic_t *v)
  * 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)
@@ -197,7 +207,8 @@ static __inline__ int atomic_dec_return(atomic_t *v)
 
 /*
  * 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)
 {
@@ -206,14 +217,15 @@ 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");
 
@@ -243,8 +255,8 @@ static __inline__ void atomic64_add(long a, atomic64_t *v)
        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");
 }
 
@@ -277,8 +289,8 @@ static __inline__ void atomic64_sub(long a, atomic64_t *v)
        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");
 }
 
@@ -309,8 +321,8 @@ static __inline__ void atomic64_inc(atomic64_t *v)
        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");
 }
 
@@ -351,8 +363,8 @@ static __inline__ void atomic64_dec(atomic64_t *v)
        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");
 }