0 and return NETDEV_TX_BUSY, but just using '> 0' and '< 1' for comparison instead of '== 0' and '!= 0' is simpler. It just warranted a mention of *why* we do it that way... Move the call to atmvcc->send() to happen *after* the accounting and potentially stopping the netdev queue, in br2684_xmit_vcc(). This matters if the ->send() call suffers an immediate failure, because it'll call br2684_pop() with the offending skb before returning. We want that to happen *after* we've done the initial accounting for the packet in question. Also make it return an appropriate success/failure indication while we're at it. Tested by running 'ping -l 1000 bottomless.aaisp.net.uk' from within my network, with only a single PPPoE-over-BR2684 link running. And after setting txqueuelen on the nas0 interface to something low (5, in fact). Before the patch, we'd see about 15 packets being queued and a resulting latency of ~56ms being reached. After the patch, we see only about 8, which is fairly much what we expect. And a max latency of ~36ms. On this OpenWRT box, wmem_default is 163840. Signed-off-by: David Woodhouse Reviewed-by: Krzysztof Mazur Signed-off-by: David S. Miller