arch/arm/include/asm/clocksource.h
arch/arm64/include/asm/clocksource.h
arch/ia64/include/asm/clocksource.h
arch/mips/include/asm/clocksource.h
arch/sparc/include/asm/clocksource.h
arch/x86/include/asm/clocksource.h
include/linux/clocksource.h