system_has_cmpxchg_double  112 arch/x86/include/asm/cmpxchg_32.h #define system_has_cmpxchg_double() cpu_has_cx8
system_has_cmpxchg_double   21 arch/x86/include/asm/cmpxchg_64.h #define system_has_cmpxchg_double() cpu_has_cx16