From: David Woodhouse <David.Woodhouse@xxxxxxxxx> With -mmovbe enabled (implicit with -march=atom), this allows the compiler to use the movbe instruction. This doesn't have a significant effect on code size (unlike on PowerPC), because the movbe instruction actually takes as many bytes to encode as a simple mov and a bswap. But for Atom in particular I believe it should give a performance win over the mov+bswap alternative. That was kind of why movbe was invented in the first place, after all... I've done basic functionality testing with IPv6 and Legacy IP, but no performance testing. The EFI firmware on my test box unfortunately no longer starts up. Signed-off-by: David Woodhouse <David.Woodhouse@xxxxxxxxx> --- arch/x86/Kconfig | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 46c3bff..238f2ea 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -194,6 +194,9 @@ config ARCH_HAS_CACHE_LINE_SIZE config ARCH_HAS_CPU_AUTOPROBE def_bool y +config ARCH_USE_BUILTIN_BSWAP + def_bool y + config HAVE_SETUP_PER_CPU_AREA def_bool y -- 1.8.0 -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
