X-Git-Url: http://git.droids-corp.org/?a=blobdiff_plain;f=drivers%2Fnet%2Faf_packet%2Frte_eth_af_packet.c;h=1396f32c3dccd800d2276245829ff49ad88271e6;hb=891f8260dd49d4bc683cffaca79b7f7d5247b968;hp=cea7091c063973f8ccfe9b750b72aaeb43472fcb;hpb=4e8a910719df270770fe35199146847bd55a7b85;p=dpdk.git

diff --git a/drivers/net/af_packet/rte_eth_af_packet.c b/drivers/net/af_packet/rte_eth_af_packet.c
index cea7091c06..1396f32c3d 100644
--- a/drivers/net/af_packet/rte_eth_af_packet.c
+++ b/drivers/net/af_packet/rte_eth_af_packet.c
@@ -237,8 +237,30 @@ eth_af_packet_tx(void *queue, struct rte_mbuf **bufs, uint16_t nb_pkts)
 		}
 
 		/* point at the next incoming frame */
-		if (!tx_ring_status_available(ppd->tp_status) &&
-		    poll(&pfd, 1, -1) < 0)
+		if (!tx_ring_status_available(ppd->tp_status)) {
+			if (poll(&pfd, 1, -1) < 0)
+				break;
+
+			/* poll() can return POLLERR if the interface is down */
+			if (pfd.revents & POLLERR)
+				break;
+		}
+
+		/*
+		 * poll() will almost always return POLLOUT, even if there
+		 * are no extra buffers available
+		 *
+		 * This happens, because packet_poll() calls datagram_poll()
+		 * which checks the space left in the socket buffer and,
+		 * in the case of packet_mmap, the default socket buffer length
+		 * doesn't match the requested size for the tx_ring.
+		 * As such, there is almost always space left in socket buffer,
+		 * which doesn't seem to be correlated to the requested size
+		 * for the tx_ring in packet_mmap.
+		 *
+		 * This results in poll() returning POLLOUT.
+		 */
+		if (!tx_ring_status_available(ppd->tp_status))
 			break;
 
 		/* copy the tx frame data */