Fedora kernel-2.6.17-1.2142_FC4 patched with stable patch-2.6.17.4-vs2.0.2-rc26.diff

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

diff --git a/include/asm-arm/atomic.h b/include/asm-arm/atomic.h
index 2885972..3d7283d 100644 (file)
--- a/include/asm-arm/atomic.h
+++ b/include/asm-arm/atomic.h
@@ -12,6 +12,7 @@
 #define __ASM_ARM_ATOMIC_H
 
 #include <linux/config.h>
+#include <linux/compiler.h>
 
 typedef struct { volatile int counter; } atomic_t;
 
@@ -80,6 +81,24 @@ static inline int atomic_sub_return(int i, atomic_t *v)
        return result;
 }
 
+static inline int atomic_cmpxchg(atomic_t *ptr, int old, int new)
+{
+       unsigned long oldval, res;
+
+       do {
+               __asm__ __volatile__("@ atomic_cmpxchg\n"
+               "ldrex  %1, [%2]\n"
+               "mov    %0, #0\n"
+               "teq    %1, %3\n"
+               "strexeq %0, %4, [%2]\n"
+                   : "=&r" (res), "=&r" (oldval)
+                   : "r" (&ptr->counter), "Ir" (old), "r" (new)
+                   : "cc");
+       } while (res);
+
+       return oldval;
+}
+
 static inline void atomic_clear_mask(unsigned long mask, unsigned long *addr)
 {
        unsigned long tmp, tmp2;
@@ -131,6 +150,20 @@ static inline int atomic_sub_return(int i, atomic_t *v)
        return val;
 }
 
+static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
+{
+       int ret;
+       unsigned long flags;
+
+       local_irq_save(flags);
+       ret = v->counter;
+       if (likely(ret == old))
+               v->counter = new;
+       local_irq_restore(flags);
+
+       return ret;
+}
+
 static inline void atomic_clear_mask(unsigned long mask, unsigned long *addr)
 {
        unsigned long flags;
@@ -142,6 +175,19 @@ static inline void atomic_clear_mask(unsigned long mask, unsigned long *addr)
 
 #endif /* __LINUX_ARM_ARCH__ */
 
+#define atomic_xchg(v, new) (xchg(&((v)->counter), new))
+
+static inline int atomic_add_unless(atomic_t *v, int a, int u)
+{
+       int c, old;
+
+       c = atomic_read(v);
+       while (c != u && (old = atomic_cmpxchg((v), c, c + a)) != c)
+               c = old;
+       return c != u;
+}
+#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)
+
 #define atomic_add(i, v)       (void) atomic_add_return(i, v)
 #define atomic_inc(v)          (void) atomic_add_return(1, v)
 #define atomic_sub(i, v)       (void) atomic_sub_return(i, v)
@@ -161,5 +207,6 @@ static inline void atomic_clear_mask(unsigned long mask, unsigned long *addr)
 #define smp_mb__before_atomic_inc()    barrier()
 #define smp_mb__after_atomic_inc()     barrier()
 
+#include <asm-generic/atomic.h>
 #endif
 #endif