Index: sys/kern/uipc_domain.c
===================================================================
--- sys/kern/uipc_domain.c
+++ sys/kern/uipc_domain.c
@@ -81,6 +81,11 @@
 static struct mtx dom_mtx;		/* domain list lock */
 MTX_SYSINIT(domain, &dom_mtx, "domain list", MTX_DEF);
 
+static CK_LIST_HEAD(, domain) fasttimo_domains =
+    CK_LIST_HEAD_INITIALIZER(fasttimo_domains);
+static CK_LIST_HEAD(, domain) slowtimo_domains =
+    CK_LIST_HEAD_INITIALIZER(slowtimo_domains);
+
 /*
  * Dummy protocol specific user requests function pointer array.
  * All functions return EOPNOTSUPP.
@@ -175,6 +180,7 @@
 	struct domain *dp = arg;
 	struct protosw *pr;
 	int flags;
+	bool has_fasttimo, has_slowtimo;
 
 	flags = atomic_load_acq_int(&dp->dom_flags);
 	if ((flags & DOMF_SUPPORTED) == 0)
@@ -192,8 +198,23 @@
 	max_datalen = MHLEN - max_hdr;
 	if (max_datalen < 1)
 		panic("%s: max_datalen < 1", __func__);
-	if (IS_DEFAULT_VNET(curvnet))
+	if (IS_DEFAULT_VNET(curvnet)) {
 		atomic_set_rel_int(&dp->dom_flags, DOMF_INITED);
+		has_fasttimo = has_slowtimo = false;
+		for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) {
+			if (pr->pr_fasttimo  != NULL)
+				has_fasttimo = true;
+			if (pr->pr_slowtimo != NULL)
+				has_slowtimo = true;
+		}
+
+		if (has_fasttimo)
+			CK_LIST_INSERT_HEAD(&fasttimo_domains, dp,
+			    dom_fasttimos);
+		if (has_slowtimo)
+			CK_LIST_INSERT_HEAD(&slowtimo_domains, dp,
+			    dom_slowtimos);
+	}
 }
 
 #ifdef VIMAGE
@@ -340,6 +361,7 @@
 	VNET_ITERATOR_DECL(vnet_iter);
 	struct domain *dp;
 	struct protosw *pr, *fpr;
+	bool has_fasttimo, has_slowtimo;
 
 	/* Sanity checks. */
 	if (family == 0)
@@ -399,6 +421,35 @@
 	}
 	VNET_LIST_RUNLOCK();
 
+	if (fpr->pr_fasttimo != NULL) {
+		has_fasttimo = false;
+		for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) {
+			if (pr != fpr && pr->pr_fasttimo != NULL) {
+				has_fasttimo = true;
+				break;
+			}
+		}
+
+		if (!has_fasttimo)
+			CK_LIST_INSERT_HEAD(&fasttimo_domains, dp,
+			    dom_fasttimos);
+	}
+
+	if (fpr->pr_slowtimo != NULL) {
+		has_slowtimo = false;
+		for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) {
+			if (pr != fpr && pr->pr_slowtimo != NULL) {
+				has_slowtimo = true;
+				break;
+			}
+		}
+
+		if (!has_slowtimo)
+			CK_LIST_INSERT_HEAD(&slowtimo_domains, dp,
+			    dom_slowtimos);
+	}
+
+
 	return (0);
 }
 
@@ -411,6 +462,7 @@
 {
 	struct domain *dp;
 	struct protosw *pr, *dpr;
+	bool has_fasttimo, has_slowtimo;
 
 	/* Sanity checks. */
 	if (family == 0)
@@ -447,6 +499,32 @@
 		return (EPROTONOSUPPORT);
 	}
 
+	if (dpr->pr_fasttimo != NULL) {
+		has_fasttimo = false;
+		for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) {
+			if (pr != dpr && pr->pr_fasttimo != NULL) {
+				has_fasttimo = true;
+				break;
+			}
+		}
+
+		if (!has_fasttimo)
+			CK_LIST_REMOVE(dp, dom_fasttimos);
+	}
+
+	if (dpr->pr_slowtimo != NULL) {
+		has_slowtimo = false;
+		for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) {
+			if (pr != dpr && pr->pr_slowtimo != NULL) {
+				has_slowtimo = true;
+				break;
+			}
+		}
+
+		if (!has_slowtimo)
+			CK_LIST_REMOVE(dp, dom_slowtimos);
+	}
+
 	/* De-orbit the protocol and make the slot available again. */
 	dpr->pr_type = 0;
 	dpr->pr_domain = dp;
@@ -488,10 +566,7 @@
 	struct protosw *pr;
 
 	NET_EPOCH_ENTER(et);
-	for (dp = domains; dp; dp = dp->dom_next) {
-		if ((atomic_load_int(&dp->dom_flags) & DOMF_INITED) == 0)
-			continue;
-		atomic_thread_fence_acq();
+	CK_LIST_FOREACH(dp, &slowtimo_domains, dom_slowtimos) {
 		for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)
 			if (pr->pr_slowtimo)
 				(*pr->pr_slowtimo)();
@@ -508,10 +583,7 @@
 	struct protosw *pr;
 
 	NET_EPOCH_ENTER(et);
-	for (dp = domains; dp; dp = dp->dom_next) {
-		if ((atomic_load_int(&dp->dom_flags) & DOMF_INITED) == 0)
-			continue;
-		atomic_thread_fence_acq();
+	CK_LIST_FOREACH(dp, &fasttimo_domains, dom_fasttimos) {
 		for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)
 			if (pr->pr_fasttimo)
 				(*pr->pr_fasttimo)();
Index: sys/sys/domain.h
===================================================================
--- sys/sys/domain.h
+++ sys/sys/domain.h
@@ -35,6 +35,8 @@
 #ifndef _SYS_DOMAIN_H_
 #define _SYS_DOMAIN_H_
 
+#include <ck_queue.h>
+
 /*
  * Structure per communications domain.
  */
@@ -69,6 +71,10 @@
 	void	*(*dom_ifattach)(struct ifnet *);
 	void	(*dom_ifdetach)(struct ifnet *, void *);
 	int	(*dom_ifmtu)(struct ifnet *);
+
+	CK_LIST_ENTRY(domain)	dom_fasttimos;
+	CK_LIST_ENTRY(domain)	dom_slowtimos;
+
 					/* af-dependent data on ifnet */
 };