netxen: fix race in tx stop queue
There is race between netif_stop_queue and netif_stopped_queue
check.So check once again if buffers are available to avoid race.
With above logic we can also get rid of tx lock in process_cmd_ring.
Signed-off-by: Rajesh Borundia <rajesh.borundia@qlogic.com>
Signed-off-by: Amit Kumar Salecha <amit.salecha@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/netxen/netxen_nic_hw.c b/drivers/net/netxen/netxen_nic_hw.c
index 29d7b93d0..10e2f13 100644
--- a/drivers/net/netxen/netxen_nic_hw.c
+++ b/drivers/net/netxen/netxen_nic_hw.c
@@ -598,8 +598,14 @@
if (nr_desc >= netxen_tx_avail(tx_ring)) {
netif_tx_stop_queue(tx_ring->txq);
- __netif_tx_unlock_bh(tx_ring->txq);
- return -EBUSY;
+ smp_mb();
+ if (netxen_tx_avail(tx_ring) > nr_desc) {
+ if (netxen_tx_avail(tx_ring) > TX_STOP_THRESH)
+ netif_tx_wake_queue(tx_ring->txq);
+ } else {
+ __netif_tx_unlock_bh(tx_ring->txq);
+ return -EBUSY;
+ }
}
do {