Function tcp_addrack

freebsd/netinet/tcp_stacks/rack.c:14895–14967

static bool rack_mod_inited = false;

static int
tcp_addrack(module_t mod, int32_t type, void *data)
{
	int32_t err = 0;
	int num_stacks;

	switch (type) {
	case MOD_LOAD:
		rack_zone = uma_zcreate(__XSTRING(MODNAME) "_map",
		    sizeof(struct rack_sendmap),
		    rack_ctor, rack_dtor, NULL, NULL, UMA_ALIGN_PTR, 0);

		rack_pcb_zone = uma_zcreate(__XSTRING(MODNAME) "_pcb",
		    sizeof(struct tcp_rack),
		    rack_ctor, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0);

		sysctl_ctx_init(&rack_sysctl_ctx);
		rack_sysctl_root = SYSCTL_ADD_NODE(&rack_sysctl_ctx,
		    SYSCTL_STATIC_CHILDREN(_net_inet_tcp),
		    OID_AUTO,
#ifdef STACKALIAS
		    __XSTRING(STACKALIAS),
#else
		    __XSTRING(STACKNAME),
#endif
		    CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
		    "");
		if (rack_sysctl_root == NULL) {
			printf("Failed to add sysctl node\n");
			err = EFAULT;
			goto free_uma;
		}
		rack_init_sysctls();
		num_stacks = nitems(rack_stack_names);
		err = register_tcp_functions_as_names(&__tcp_rack, M_WAITOK,
		    rack_stack_names, &num_stacks);
		if (err) {
			printf("Failed to register %s stack name for "
			    "%s module\n", rack_stack_names[num_stacks],
			    __XSTRING(MODNAME));
			sysctl_ctx_free(&rack_sysctl_ctx);
free_uma:
			uma_zdestroy(rack_zone);
			uma_zdestroy(rack_pcb_zone);
			rack_counter_destroy();
			printf("Failed to register rack module -- err:%d\n", err);
			return (err);
		}
		tcp_lro_reg_mbufq();
		rack_mod_inited = true;
		break;
	case MOD_QUIESCE:
		err = deregister_tcp_functions(&__tcp_rack, true, false);
		break;
	case MOD_UNLOAD:
		err = deregister_tcp_functions(&__tcp_rack, false, true);
		if (err == EBUSY)
			break;