lwkt_alloc_thread
td2 = lwkt_alloc_thread(NULL, LWKT_THREAD_STACK, gd->gd_cpuid, 0);
td = lwkt_alloc_thread(NULL, stksize, -1, 0);
td = lwkt_alloc_thread(NULL, LWKT_THREAD_STACK, cpu, flags);
td = lwkt_alloc_thread(template, LWKT_THREAD_STACK, cpu,
struct thread *lwkt_alloc_thread(struct thread *, int, int, int);