timer_settime

arm/disarm and fetch state of POSIX per-process timer

sys_timer_settime(timer_t timer_id, int flags, const struct __kernel_itimerspec *new_setting, struct __kernel_itimerspec *old_setting)

register	value
`rax`	223, the syscall number
`rdi`	timer_t timer_id
`rsi`	int flags
`rdx`	const struct __kernel_itimerspec *new_setting
`r10`	struct __kernel_itimerspec *old_setting
`rax`	the return value

Then run syscall to enter the kernel.

Same syscall on other architectures