Merge branch 'for-davem' of git://git.kernel.org/pub/scm/linux/kernel/git/bwh/sfc-next-2.6

4 files changed, 35 insertions, 115 deletions

diff --git a/drivers/net/sfc/efx.c b/drivers/net/sfc/efx.c
index 2166c1d0a53..711449c6e67 100644
--- a/drivers/net/sfc/efx.c
+++ b/drivers/net/sfc/efx.c
@@ -461,9 +461,6 @@ efx_alloc_channel(struct efx_nic *efx, int i, struct efx_channel *old_channel)
 		}
 	}
 
-	spin_lock_init(&channel->tx_stop_lock);
-	atomic_set(&channel->tx_stop_count, 1);
-
 	rx_queue = &channel->rx_queue;
 	rx_queue->efx = efx;
 	setup_timer(&rx_queue->slow_fill, efx_rx_slow_fill,
@@ -1406,11 +1403,11 @@ static void efx_start_all(struct efx_nic *efx)
 	 * restart the transmit interface early so the watchdog timer stops */
 	efx_start_port(efx);
 
-	efx_for_each_channel(channel, efx) {
-		if (efx_dev_registered(efx))
-			efx_wake_queue(channel);
+	if (efx_dev_registered(efx))
+		netif_tx_wake_all_queues(efx->net_dev);
+
+	efx_for_each_channel(channel, efx)
 		efx_start_channel(channel);
-	}
 
 	if (efx->legacy_irq)
 		efx->legacy_irq_enabled = true;
@@ -1498,9 +1495,7 @@ static void efx_stop_all(struct efx_nic *efx)
 	/* Stop the kernel transmit interface late, so the watchdog
 	 * timer isn't ticking over the flush */
 	if (efx_dev_registered(efx)) {
-		struct efx_channel *channel;
-		efx_for_each_channel(channel, efx)
-			efx_stop_queue(channel);
+		netif_tx_stop_all_queues(efx->net_dev);
 		netif_tx_lock_bh(efx->net_dev);
 		netif_tx_unlock_bh(efx->net_dev);
 	}
@@ -1896,6 +1891,7 @@ static DEVICE_ATTR(phy_type, 0644, show_phy_type, NULL);
 static int efx_register_netdev(struct efx_nic *efx)
 {
 	struct net_device *net_dev = efx->net_dev;
+	struct efx_channel *channel;
 	int rc;
 
 	net_dev->watchdog_timeo = 5 * HZ;
@@ -1918,6 +1914,14 @@ static int efx_register_netdev(struct efx_nic *efx)
 	if (rc)
 		goto fail_locked;
 
+	efx_for_each_channel(channel, efx) {
+		struct efx_tx_queue *tx_queue;
+		efx_for_each_channel_tx_queue(tx_queue, channel) {
+			tx_queue->core_txq = netdev_get_tx_queue(
+				efx->net_dev, tx_queue->queue / EFX_TXQ_TYPES);
+		}
+	}
+
 	/* Always start with carrier off; PHY events will detect the link */
 	netif_carrier_off(efx->net_dev);
 
diff --git a/drivers/net/sfc/efx.h b/drivers/net/sfc/efx.h
index 003fdb35b4b..d43a7e5212b 100644
--- a/drivers/net/sfc/efx.h
+++ b/drivers/net/sfc/efx.h
@@ -36,8 +36,6 @@ efx_hard_start_xmit(struct sk_buff *skb, struct net_device *net_dev);
 extern netdev_tx_t
 efx_enqueue_skb(struct efx_tx_queue *tx_queue, struct sk_buff *skb);
 extern void efx_xmit_done(struct efx_tx_queue *tx_queue, unsigned int index);
-extern void efx_stop_queue(struct efx_channel *channel);
-extern void efx_wake_queue(struct efx_channel *channel);
 
 /* RX */
 extern int efx_probe_rx_queue(struct efx_rx_queue *rx_queue);
diff --git a/drivers/net/sfc/net_driver.h b/drivers/net/sfc/net_driver.h
index 76f2fb197f0..bdce66ddf93 100644
--- a/drivers/net/sfc/net_driver.h
+++ b/drivers/net/sfc/net_driver.h
@@ -136,6 +136,7 @@ struct efx_tx_buffer {
  * @efx: The associated Efx NIC
  * @queue: DMA queue number
  * @channel: The associated channel
+ * @core_txq: The networking core TX queue structure
  * @buffer: The software buffer ring
  * @txd: The hardware descriptor ring
  * @ptr_mask: The size of the ring minus 1.
@@ -148,8 +149,6 @@ struct efx_tx_buffer {
  *	variable indicates that the queue is empty.  This is to
  *	avoid cache-line ping-pong between the xmit path and the
  *	completion path.
- * @stopped: Stopped count.
- *	Set if this TX queue is currently stopping its port.
  * @insert_count: Current insert pointer
  *	This is the number of buffers that have been added to the
  *	software ring.
@@ -179,7 +178,7 @@ struct efx_tx_queue {
 	struct efx_nic *efx ____cacheline_aligned_in_smp;
 	unsigned queue;
 	struct efx_channel *channel;
-	struct efx_nic *nic;
+	struct netdev_queue *core_txq;
 	struct efx_tx_buffer *buffer;
 	struct efx_special_buffer txd;
 	unsigned int ptr_mask;
@@ -188,7 +187,6 @@ struct efx_tx_queue {
 	/* Members used mainly on the completion path */
 	unsigned int read_count ____cacheline_aligned_in_smp;
 	unsigned int old_write_count;
-	int stopped;
 
 	/* Members used only on the xmit path */
 	unsigned int insert_count ____cacheline_aligned_in_smp;
@@ -321,7 +319,6 @@ enum efx_rx_alloc_method {
  * @irq_moderation: IRQ moderation value (in hardware ticks)
  * @napi_dev: Net device used with NAPI
  * @napi_str: NAPI control structure
- * @reset_work: Scheduled reset work thread
  * @work_pending: Is work pending via NAPI?
  * @eventq: Event queue buffer
  * @eventq_mask: Event queue pointer mask
@@ -342,8 +339,6 @@ enum efx_rx_alloc_method {
  * @n_rx_overlength: Count of RX_OVERLENGTH errors
  * @n_skbuff_leaks: Count of skbuffs leaked due to RX overrun
  * @rx_queue: RX queue for this channel
- * @tx_stop_count: Core TX queue stop count
- * @tx_stop_lock: Core TX queue stop lock
  * @tx_queue: TX queues for this channel
  */
 struct efx_channel {
@@ -382,10 +377,6 @@ struct efx_channel {
 	bool rx_pkt_csummed;
 
 	struct efx_rx_queue rx_queue;
-
-	atomic_t tx_stop_count;
-	spinlock_t tx_stop_lock;
-
 	struct efx_tx_queue tx_queue[2];
 };
 
diff --git a/drivers/net/sfc/tx.c b/drivers/net/sfc/tx.c
index bdb92b4af68..2f5e9da657b 100644
--- a/drivers/net/sfc/tx.c
+++ b/drivers/net/sfc/tx.c
@@ -30,50 +30,6 @@
  */
 #define EFX_TXQ_THRESHOLD(_efx) ((_efx)->txq_entries / 2u)
 
-/* We need to be able to nest calls to netif_tx_stop_queue(), partly
- * because of the 2 hardware queues associated with each core queue,
- * but also so that we can inhibit TX for reasons other than a full
- * hardware queue. */
-void efx_stop_queue(struct efx_channel *channel)
-{
-	struct efx_nic *efx = channel->efx;
-	struct efx_tx_queue *tx_queue = efx_channel_get_tx_queue(channel, 0);
-
-	if (!tx_queue)
-		return;
-
-	spin_lock_bh(&channel->tx_stop_lock);
-	netif_vdbg(efx, tx_queued, efx->net_dev, "stop TX queue\n");
-
-	atomic_inc(&channel->tx_stop_count);
-	netif_tx_stop_queue(
-		netdev_get_tx_queue(efx->net_dev,
-				    tx_queue->queue / EFX_TXQ_TYPES));
-
-	spin_unlock_bh(&channel->tx_stop_lock);
-}
-
-/* Decrement core TX queue stop count and wake it if the count is 0 */
-void efx_wake_queue(struct efx_channel *channel)
-{
-	struct efx_nic *efx = channel->efx;
-	struct efx_tx_queue *tx_queue = efx_channel_get_tx_queue(channel, 0);
-
-	if (!tx_queue)
-		return;
-
-	local_bh_disable();
-	if (atomic_dec_and_lock(&channel->tx_stop_count,
-				&channel->tx_stop_lock)) {
-		netif_vdbg(efx, tx_queued, efx->net_dev, "waking TX queue\n");
-		netif_tx_wake_queue(
-			netdev_get_tx_queue(efx->net_dev,
-					    tx_queue->queue / EFX_TXQ_TYPES));
-		spin_unlock(&channel->tx_stop_lock);
-	}
-	local_bh_enable();
-}
-
 static void efx_dequeue_buffer(struct efx_tx_queue *tx_queue,
 			       struct efx_tx_buffer *buffer)
 {
@@ -234,9 +190,9 @@ netdev_tx_t efx_enqueue_skb(struct efx_tx_queue *tx_queue, struct sk_buff *skb)
 				 * checked.  Update the xmit path's
 				 * copy of read_count.
 				 */
-				++tx_queue->stopped;
+				netif_tx_stop_queue(tx_queue->core_txq);
 				/* This memory barrier protects the
-				 * change of stopped from the access
+				 * change of queue state from the access
 				 * of read_count. */
 				smp_mb();
 				tx_queue->old_read_count =
@@ -244,10 +200,12 @@ netdev_tx_t efx_enqueue_skb(struct efx_tx_queue *tx_queue, struct sk_buff *skb)
 				fill_level = (tx_queue->insert_count
 					      - tx_queue->old_read_count);
 				q_space = efx->txq_entries - 1 - fill_level;
-				if (unlikely(q_space-- <= 0))
-					goto stop;
+				if (unlikely(q_space-- <= 0)) {
+					rc = NETDEV_TX_BUSY;
+					goto unwind;
+				}
 				smp_mb();
-				--tx_queue->stopped;
+				netif_tx_start_queue(tx_queue->core_txq);
 			}
 
 			insert_ptr = tx_queue->insert_count & tx_queue->ptr_mask;
@@ -307,13 +265,6 @@ netdev_tx_t efx_enqueue_skb(struct efx_tx_queue *tx_queue, struct sk_buff *skb)
 
 	/* Mark the packet as transmitted, and free the SKB ourselves */
 	dev_kfree_skb_any(skb);
-	goto unwind;
-
- stop:
-	rc = NETDEV_TX_BUSY;
-
-	if (tx_queue->stopped == 1)
-		efx_stop_queue(tx_queue->channel);
 
  unwind:
 	/* Work backwards until we hit the original insert pointer value */
@@ -400,32 +351,21 @@ void efx_xmit_done(struct efx_tx_queue *tx_queue, unsigned int index)
 {
 	unsigned fill_level;
 	struct efx_nic *efx = tx_queue->efx;
-	struct netdev_queue *queue;
 
 	EFX_BUG_ON_PARANOID(index > tx_queue->ptr_mask);
 
 	efx_dequeue_buffers(tx_queue, index);
 
 	/* See if we need to restart the netif queue.  This barrier
-	 * separates the update of read_count from the test of
-	 * stopped. */
+	 * separates the update of read_count from the test of the
+	 * queue state. */
 	smp_mb();
-	if (unlikely(tx_queue->stopped) && likely(efx->port_enabled)) {
+	if (unlikely(netif_tx_queue_stopped(tx_queue->core_txq)) &&
+	    likely(efx->port_enabled)) {
 		fill_level = tx_queue->insert_count - tx_queue->read_count;
 		if (fill_level < EFX_TXQ_THRESHOLD(efx)) {
 			EFX_BUG_ON_PARANOID(!efx_dev_registered(efx));
-
-			/* Do this under netif_tx_lock(), to avoid racing
-			 * with efx_xmit(). */
-			queue = netdev_get_tx_queue(
-				efx->net_dev,
-				tx_queue->queue / EFX_TXQ_TYPES);
-			__netif_tx_lock(queue, smp_processor_id());
-			if (tx_queue->stopped) {
-				tx_queue->stopped = 0;
-				efx_wake_queue(tx_queue->channel);
-			}
-			__netif_tx_unlock(queue);
+			netif_tx_wake_queue(tx_queue->core_txq);
 		}
 	}
 
@@ -487,7 +427,6 @@ void efx_init_tx_queue(struct efx_tx_queue *tx_queue)
 	tx_queue->read_count = 0;
 	tx_queue->old_read_count = 0;
 	tx_queue->empty_read_count = 0 | EFX_EMPTY_COUNT_VALID;
-	BUG_ON(tx_queue->stopped);
 
 	/* Set up TX descriptor ring */
 	efx_nic_init_tx(tx_queue);
@@ -523,12 +462,6 @@ void efx_fini_tx_queue(struct efx_tx_queue *tx_queue)
 
 	/* Free up TSO header cache */
 	efx_fini_tso(tx_queue);
-
-	/* Release queue's stop on port, if any */
-	if (tx_queue->stopped) {
-		tx_queue->stopped = 0;
-		efx_wake_queue(tx_queue->channel);
-	}
 }
 
 void efx_remove_tx_queue(struct efx_tx_queue *tx_queue)
@@ -770,9 +703,9 @@ static int efx_tx_queue_insert(struct efx_tx_queue *tx_queue,
 			 * since the xmit path last checked.  Update
 			 * the xmit path's copy of read_count.
 			 */
-			++tx_queue->stopped;
+			netif_tx_stop_queue(tx_queue->core_txq);
 			/* This memory barrier protects the change of
-			 * stopped from the access of read_count. */
+			 * queue state from the access of read_count. */
 			smp_mb();
 			tx_queue->old_read_count =
 				ACCESS_ONCE(tx_queue->read_count);
@@ -784,7 +717,7 @@ static int efx_tx_queue_insert(struct efx_tx_queue *tx_queue,
 				return 1;
 			}
 			smp_mb();
-			--tx_queue->stopped;
+			netif_tx_start_queue(tx_queue->core_txq);
 		}
 
 		insert_ptr = tx_queue->insert_count & tx_queue->ptr_mask;
@@ -1124,8 +1057,10 @@ static int efx_enqueue_skb_tso(struct efx_tx_queue *tx_queue,
 
 	while (1) {
 		rc = tso_fill_packet_with_fragment(tx_queue, skb, &state);
-		if (unlikely(rc))
-			goto stop;
+		if (unlikely(rc)) {
+			rc2 = NETDEV_TX_BUSY;
+			goto unwind;
+		}
 
 		/* Move onto the next fragment? */
 		if (state.in_len == 0) {
@@ -1154,14 +1089,6 @@ static int efx_enqueue_skb_tso(struct efx_tx_queue *tx_queue,
 	netif_err(efx, tx_err, efx->net_dev,
 		  "Out of memory for TSO headers, or PCI mapping error\n");
 	dev_kfree_skb_any(skb);
-	goto unwind;
-
- stop:
-	rc2 = NETDEV_TX_BUSY;
-
-	/* Stop the queue if it wasn't stopped before. */
-	if (tx_queue->stopped == 1)
-		efx_stop_queue(tx_queue->channel);
 
  unwind:
 	/* Free the DMA mapping we were in the process of writing out */