There''s no need for a loop here: if the value to be compared against
and the value to be stored are equal, cmpxchg{,8b} act just like a
load anyway.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
--- a/xen/include/asm-x86/x86_32/page.h
+++ b/xen/include/asm-x86/x86_32/page.h
@@ -84,11 +84,7 @@ extern unsigned int PAGE_HYPERVISOR_NOCA
#endif
-#define pte_read_atomic(ptep) ({ \
- intpte_t __pte = *(ptep), __npte; \
- while ( (__npte = cmpxchg(ptep, __pte, __pte)) != __pte ) \
- __pte = __npte; \
- __pte; })
+#define pte_read_atomic(ptep) cmpxchg(ptep, 0, 0)
#define pte_write_atomic(ptep, pte) do { \
intpte_t __pte = *(ptep), __npte; \
while ( (__npte = cmpxchg(ptep, __pte, (pte))) != __pte ) \
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