Implementation of xchg primitives derived from MIT license

[urcu.git] / arch_x86.h

diff --git a/arch_x86.h b/arch_x86.h
index e899684b56ddc50b9c43b506e6cb3ccdd6f254d0..cc3ab012c557f38db5df6c7b5c829a13ceaf511a 100644 (file)
--- a/arch_x86.h
+++ b/arch_x86.h
@@ -23,6 +23,7 @@
  */
 
 #include <compiler.h>
+#include <arch_atomic.h>
 
 /* Assume P4 or newer */
 #define CONFIG_HAVE_FENCE 1
@@ -94,56 +95,6 @@ static inline void cpu_relax(void)
        rep_nop();
 }
 
-#define xchg(ptr, v)   \
-       ((__typeof__(*(ptr)))__xchg((ptr), (unsigned long)(v), sizeof(*(ptr))))
-
-struct __xchg_ptr_as_array {
-       unsigned long a[100];
-};
-
-#define __xchg_ptr_as_array(x) ((struct __xchg_ptr_as_array *)(x))
-
-/*
- * xchg always implies a "lock" prefix, even on UP. See Intel documentation.
- * volatile attribute is neccessary due to xchg side effect.
- * *ptr is an output argument.
- * x is considered local, ptr is considered remote.
- */
-static inline unsigned long __xchg(volatile void *ptr, unsigned long x,
-                                  int size)
-{
-       switch (size) {
-       case 1:
-               asm volatile("xchgb %b0,%1"
-                            : "=q" (x)
-                            : "m" (*__xchg_ptr_as_array(ptr)), "0" (x)
-                            : "memory");
-               break;
-       case 2:
-               asm volatile("xchgw %w0,%1"
-                            : "=r" (x)
-                            : "m" (*__xchg_ptr_as_array(ptr)), "0" (x)
-                            : "memory");
-               break;
-       case 4:
-               asm volatile("xchgl %k0,%1"
-                            : "=r" (x)
-                            : "m" (*__xchg_ptr_as_array(ptr)), "0" (x)
-                            : "memory");
-               break;
-#if (BITS_PER_LONG == 64)
-       case 8:
-               asm volatile("xchgq %0,%1"
-                            : "=r" (x)
-                            : "m" (*__xchg_ptr_as_array(ptr)), "0" (x)
-                            : "memory");
-               break;
-#endif
-       }
-       smp_wmc();
-       return x;
-}
-
 #define rdtscll(val)                                                     \
        do {                                                              \
             unsigned int __a, __d;                                       \