wfe 12 arch/arm/include/asm/barrier.h #define wfe() __asm__ __volatile__ ("wfe" : : : "memory") wfe 15 arch/arm/include/asm/barrier.h #define wfe() do { } while (0) wfe 18 arch/arm64/include/asm/barrier.h #define wfe() asm volatile("wfe" : : : "memory")