diff --git a/sys/net/if_epair.c b/sys/net/if_epair.c
index 818f25f0c..36c37b84f 100644
--- a/sys/net/if_epair.c
+++ b/sys/net/if_epair.c
@@ -98,11 +98,15 @@ static unsigned int next_index = 0;
 #define	EPAIR_LOCK()			mtx_lock(&epair_n_index_mtx)
 #define	EPAIR_UNLOCK()			mtx_unlock(&epair_n_index_mtx)
 
+#define BIT_QUEUE_TASK		0
+#define BIT_MBUF_QUEUED		1
+
 struct epair_softc;
 struct epair_queue {
 	int			 id;
 	struct buf_ring		*rxring[2];
 	volatile int		 ridx;		/* 0 || 1 */
+	volatile int		 state;		/* queue state */
 	struct task		 tx_task;
 	struct epair_softc	*sc;
 };
@@ -171,7 +175,8 @@ epair_tx_start_deferred(void *arg, int pending)
 	} while (!atomic_fcmpset_int(&q->ridx, &ridx, nidx));
 	epair_if_input(sc, q, ridx);
 
-	if (! buf_ring_empty(q->rxring[nidx]))
+	atomic_clear_int(&q->state, (1 << BIT_QUEUE_TASK));
+	if (atomic_testandclear_int(&q->state, BIT_MBUF_QUEUED))
 		taskqueue_enqueue(epair_tasks.tq[q->id], &q->tx_task);
 
 	if_rele(sc->ifp);
@@ -186,7 +191,6 @@ epair_menq(struct mbuf *m, struct epair_softc *osc)
 	short mflags;
 	struct epair_queue *q = NULL;
 	uint32_t bucket;
-	bool was_empty;
 #ifdef RSS
 	struct ether_header *eh;
 #endif
@@ -234,8 +238,8 @@ epair_menq(struct mbuf *m, struct epair_softc *osc)
 #endif
 	q = &osc->queues[bucket];
 
+	atomic_set_int(&q->state, (1 << BIT_MBUF_QUEUED));
 	ridx = atomic_load_int(&q->ridx);
-	was_empty = buf_ring_empty(q->rxring[ridx]);
 	ret = buf_ring_enqueue(q->rxring[ridx], m);
 	if (ret != 0) {
 		/* Ring is full. */
@@ -256,10 +260,11 @@ epair_menq(struct mbuf *m, struct epair_softc *osc)
 	/* Someone else received the packet. */
 	if_inc_counter(oifp, IFCOUNTER_IPACKETS, 1);
 
-done:
-	if (was_empty)
+	if (!atomic_testandset_int(&q->state, BIT_QUEUE_TASK)) {
 		taskqueue_enqueue(epair_tasks.tq[bucket], &q->tx_task);
+	}
 
+done:
 	return (0);
 }
 
@@ -304,9 +309,11 @@ epair_transmit(struct ifnet *ifp, struct mbuf *m)
 {
 	struct epair_softc *sc;
 	struct ifnet *oifp;
-	int error, len;
+	int error;
+#ifdef ALTQ
+	int len;
 	short mflags;
-
+#endif
 	if (m == NULL)
 		return (0);
 	M_ASSERTPKTHDR(m);
@@ -342,10 +349,11 @@ epair_transmit(struct ifnet *ifp, struct mbuf *m)
 		m_freem(m);
 		return (0);
 	}
+
+#ifdef ALTQ
 	len = m->m_pkthdr.len;
 	mflags = m->m_flags;
 
-#ifdef ALTQ
 	/* Support ALTQ via the classic if_start() path. */
 	IF_LOCK(&ifp->if_snd);
 	if (ALTQ_IS_ENABLED(&ifp->if_snd)) {
@@ -538,6 +546,7 @@ epair_clone_create(struct if_clone *ifc, char *name, size_t len, caddr_t params)
 		q->rxring[0] = buf_ring_alloc(RXRSIZE, M_EPAIR, M_WAITOK, NULL);
 		q->rxring[1] = buf_ring_alloc(RXRSIZE, M_EPAIR, M_WAITOK, NULL);
 		q->ridx = 0;
+		q->state = 0;
 		q->sc = sca;
 		NET_TASK_INIT(&q->tx_task, 0, epair_tx_start_deferred, q);
 	}
@@ -560,6 +569,7 @@ epair_clone_create(struct if_clone *ifc, char *name, size_t len, caddr_t params)
 		q->rxring[0] = buf_ring_alloc(RXRSIZE, M_EPAIR, M_WAITOK, NULL);
 		q->rxring[1] = buf_ring_alloc(RXRSIZE, M_EPAIR, M_WAITOK, NULL);
 		q->ridx = 0;
+		q->state = 0;
 		q->sc = scb;
 		NET_TASK_INIT(&q->tx_task, 0, epair_tx_start_deferred, q);
 	}