net: do not abort bulk send on BQL status

[ Upstream commit fe60faa5063822f2d555f4f326c7dd72a60929bf ]

Before calling dev_hard_start_xmit(), upper layers tried
to cook optimal skb list based on BQL budget.

Problem is that GSO packets can end up comsuming more than
the BQL budget.

Breaking the loop is not useful, since requeued packets
are ahead of any packets still in the qdisc.

It is also more expensive, since next TX completion will
push these packets later, while skbs are not in cpu caches.

It is also a behavior difference with TSO packets, that can
break the BQL limit by a large amount.

Note that drivers should use __netdev_tx_sent_queue()
in order to have optimal xmit_more support, and avoid
useless atomic operations as shown in the following patch.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/net/core/dev.c b/net/core/dev.c
index 18a5154e2f254db21121fc8207d761e3e191e5e9..903c6242b44992c08d22522ee44d67872c4ff343 100644 (file)
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -2801,7 +2801,7 @@ struct sk_buff *dev_hard_start_xmit(struct sk_buff *first, struct net_device *de
                }
 
                skb = next;
-               if (netif_xmit_stopped(txq) && skb) {
+               if (netif_tx_queue_stopped(txq) && skb) {
                        rc = NETDEV_TX_BUSY;
                        break;
                }