it's better to call the kernrel api insteaad user space api in kernel Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
here is the reason: 1.clock_systime_timespec(core function) always exist regardless the setting 2.CLOCK_MONOTONIC is a foundamental clock type required by many places Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>