packet: fix packet_direct_xmit for BQL enabled drivers

Currently, in packet_direct_xmit() we test the assigned netdevice queue
for netif_xmit_frozen_or_stopped() before doing an ndo_start_xmit().

This can have the side-effect that BQL enabled drivers which make use
of netdev_tx_sent_queue() internally, set __QUEUE_STATE_STACK_XOFF from
within the stack and would not fully fill the device's TX ring from
packet sockets with PACKET_QDISC_BYPASS enabled.

Instead, use a test without BQL bit so that bursts can be absorbed
into the NICs TX ring. Fix and code suggested by Eric Dumazet, thanks!

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 1 insertions, 1 deletions

diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index c81a9719b5b2..72e0c71fb01d 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -261,7 +261,7 @@ static int packet_direct_xmit(struct sk_buff *skb)
         local_bh_disable();
 
         HARD_TX_LOCK(dev, txq, smp_processor_id());
-        if (!netif_xmit_frozen_or_stopped(txq)) {
+        if (!netif_xmit_frozen_or_drv_stopped(txq)) {
                 ret = ops->ndo_start_xmit(skb, dev);
                 if (ret == NETDEV_TX_OK)
                         txq_trans_update(txq);