net: ethernet: sxgbe: remove private tx queue lock
The driver uses a private lock for synchronization of the xmit function and
the xmit completion handler, but since the NETIF_F_LLTX flag is not set,
the xmit function is also called with the xmit_lock held.
On the other hand the completion handler uses the reverse locking order by
first taking the private lock and (in case that the tx queue had been
stopped) then the xmit_lock.
Improve the locking by removing the private lock and using only the
xmit_lock for synchronization instead.
Signed-off-by: Lino Sanfilippo <LinoSanfilippo@gmx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/samsung/sxgbe/sxgbe_common.h b/drivers/net/ethernet/samsung/sxgbe/sxgbe_common.h
index 5cb51b6..c61f260 100644
--- a/drivers/net/ethernet/samsung/sxgbe/sxgbe_common.h
+++ b/drivers/net/ethernet/samsung/sxgbe/sxgbe_common.h
@@ -384,7 +384,6 @@
dma_addr_t *tx_skbuff_dma;
struct sk_buff **tx_skbuff;
struct timer_list txtimer;
- spinlock_t tx_lock; /* lock for tx queues */
unsigned int cur_tx;
unsigned int dirty_tx;
u32 tx_count_frames;
diff --git a/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c b/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c
index 5dbe406..cddcff5 100644
--- a/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c
+++ b/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c
@@ -426,9 +426,6 @@
tx_ring->dirty_tx = 0;
tx_ring->cur_tx = 0;
- /* initialise TX queue lock */
- spin_lock_init(&tx_ring->tx_lock);
-
return 0;
dmamem_err:
@@ -743,7 +740,7 @@
dev_txq = netdev_get_tx_queue(priv->dev, queue_no);
- spin_lock(&tqueue->tx_lock);
+ __netif_tx_lock(dev_txq, smp_processor_id());
priv->xstats.tx_clean++;
while (tqueue->dirty_tx != tqueue->cur_tx) {
@@ -781,18 +778,13 @@
/* wake up queue */
if (unlikely(netif_tx_queue_stopped(dev_txq) &&
- sxgbe_tx_avail(tqueue, tx_rsize) > SXGBE_TX_THRESH(priv))) {
- netif_tx_lock(priv->dev);
- if (netif_tx_queue_stopped(dev_txq) &&
- sxgbe_tx_avail(tqueue, tx_rsize) > SXGBE_TX_THRESH(priv)) {
- if (netif_msg_tx_done(priv))
- pr_debug("%s: restart transmit\n", __func__);
- netif_tx_wake_queue(dev_txq);
- }
- netif_tx_unlock(priv->dev);
+ sxgbe_tx_avail(tqueue, tx_rsize) > SXGBE_TX_THRESH(priv))) {
+ if (netif_msg_tx_done(priv))
+ pr_debug("%s: restart transmit\n", __func__);
+ netif_tx_wake_queue(dev_txq);
}
- spin_unlock(&tqueue->tx_lock);
+ __netif_tx_unlock(dev_txq);
}
/**
@@ -1304,9 +1296,6 @@
tqueue->hwts_tx_en)))
ctxt_desc_req = 1;
- /* get the spinlock */
- spin_lock(&tqueue->tx_lock);
-
if (priv->tx_path_in_lpi_mode)
sxgbe_disable_eee_mode(priv);
@@ -1316,8 +1305,6 @@
netdev_err(dev, "%s: Tx Ring is full when %d queue is awake\n",
__func__, txq_index);
}
- /* release the spin lock in case of BUSY */
- spin_unlock(&tqueue->tx_lock);
return NETDEV_TX_BUSY;
}
@@ -1436,8 +1423,6 @@
priv->hw->dma->enable_dma_transmission(priv->ioaddr, txq_index);
- spin_unlock(&tqueue->tx_lock);
-
return NETDEV_TX_OK;
}