syscall1_args
int sys_syscall1(struct thread *, struct syscall1_args *);
{ .sy_narg = AS(syscall1_args), .sy_call = (sy_call_t *)sys_syscall1, .sy_auevent = AUE_NULL, .sy_flags = 0, .sy_thrcnt = SY_THR_STATIC }, /* 1 = syscall1 */
struct syscall1_args *p = params;