Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Minor overlapping changes, nothing serious.

Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/sfc/ef10.c

@@ -2853,11 +2853,24 @@ efx_ef10_handle_tx_event(struct efx_channel *channel, efx_qword_t *event)
 	}
 
 	/* Transmit timestamps are only available for 8XXX series. They result
-	 * in three events per packet. These occur in order, and are:
-	 *  - the normal completion event
+	 * in up to three events per packet. These occur in order, and are:
+	 *  - the normal completion event (may be omitted)
 	 *  - the low part of the timestamp
 	 *  - the high part of the timestamp
 	 *
+	 * It's possible for multiple completion events to appear before the
+	 * corresponding timestamps. So we can for example get:
+	 *  COMP N
+	 *  COMP N+1
+	 *  TS_LO N
+	 *  TS_HI N
+	 *  TS_LO N+1
+	 *  TS_HI N+1
+	 *
+	 * In addition it's also possible for the adjacent completions to be
+	 * merged, so we may not see COMP N above. As such, the completion
+	 * events are not very useful here.
+	 *
 	 * Each part of the timestamp is itself split across two 16 bit
 	 * fields in the event.
 	 */
@@ -2865,17 +2878,7 @@ efx_ef10_handle_tx_event(struct efx_channel *channel, efx_qword_t *event)
 
 	switch (tx_ev_type) {
 	case TX_TIMESTAMP_EVENT_TX_EV_COMPLETION:
-		/* In case of Queue flush or FLR, we might have received
-		 * the previous TX completion event but not the Timestamp
-		 * events.
-		 */
-		if (tx_queue->completed_desc_ptr != tx_queue->ptr_mask)
-			efx_xmit_done(tx_queue, tx_queue->completed_desc_ptr);
-
-		tx_ev_desc_ptr = EFX_QWORD_FIELD(*event,
-						 ESF_DZ_TX_DESCR_INDX);
-		tx_queue->completed_desc_ptr =
-					tx_ev_desc_ptr & tx_queue->ptr_mask;
+		/* Ignore this event - see above. */
 		break;
 
 	case TX_TIMESTAMP_EVENT_TX_EV_TSTAMP_LO:
@@ -2887,8 +2890,7 @@ efx_ef10_handle_tx_event(struct efx_channel *channel, efx_qword_t *event)
 		ts_part = efx_ef10_extract_event_ts(event);
 		tx_queue->completed_timestamp_major = ts_part;
 
-		efx_xmit_done(tx_queue, tx_queue->completed_desc_ptr);
-		tx_queue->completed_desc_ptr = tx_queue->ptr_mask;
+		efx_xmit_done_single(tx_queue);
 		break;
 
 	default:

drivers/net/ethernet/sfc/efx.h

@@ -20,6 +20,7 @@ netdev_tx_t efx_hard_start_xmit(struct sk_buff *skb,
 				struct net_device *net_dev);
 netdev_tx_t efx_enqueue_skb(struct efx_tx_queue *tx_queue, struct sk_buff *skb);
 void efx_xmit_done(struct efx_tx_queue *tx_queue, unsigned int index);
+void efx_xmit_done_single(struct efx_tx_queue *tx_queue);
 int efx_setup_tc(struct net_device *net_dev, enum tc_setup_type type,
 		 void *type_data);
 extern unsigned int efx_piobuf_size;

drivers/net/ethernet/sfc/efx_channels.c

@@ -600,6 +600,7 @@ struct efx_channel *efx_copy_channel(const struct efx_channel *old_channel)
 		if (tx_queue->channel)
 			tx_queue->channel = channel;
 		tx_queue->buffer = NULL;
+		tx_queue->cb_page = NULL;
 		memset(&tx_queue->txd, 0, sizeof(tx_queue->txd));
 	}
 

drivers/net/ethernet/sfc/net_driver.h

@@ -208,8 +208,6 @@ struct efx_tx_buffer {
  *	avoid cache-line ping-pong between the xmit path and the
  *	completion path.
  * @merge_events: Number of TX merged completion events
- * @completed_desc_ptr: Most recent completed pointer - only used with
- *      timestamping.
  * @completed_timestamp_major: Top part of the most recent tx timestamp.
  * @completed_timestamp_minor: Low part of the most recent tx timestamp.
  * @insert_count: Current insert pointer
@@ -269,7 +267,6 @@ struct efx_tx_queue {
 	unsigned int merge_events;
 	unsigned int bytes_compl;
 	unsigned int pkts_compl;
-	unsigned int completed_desc_ptr;
 	u32 completed_timestamp_major;
 	u32 completed_timestamp_minor;
 

drivers/net/ethernet/sfc/tx.c

@@ -534,6 +534,44 @@ netdev_tx_t efx_hard_start_xmit(struct sk_buff *skb,
 	return efx_enqueue_skb(tx_queue, skb);
 }
 
+void efx_xmit_done_single(struct efx_tx_queue *tx_queue)
+{
+	unsigned int pkts_compl = 0, bytes_compl = 0;
+	unsigned int read_ptr;
+	bool finished = false;
+
+	read_ptr = tx_queue->read_count & tx_queue->ptr_mask;
+
+	while (!finished) {
+		struct efx_tx_buffer *buffer = &tx_queue->buffer[read_ptr];
+
+		if (!efx_tx_buffer_in_use(buffer)) {
+			struct efx_nic *efx = tx_queue->efx;
+
+			netif_err(efx, hw, efx->net_dev,
+				  "TX queue %d spurious single TX completion\n",
+				  tx_queue->queue);
+			efx_schedule_reset(efx, RESET_TYPE_TX_SKIP);
+			return;
+		}
+
+		/* Need to check the flag before dequeueing. */
+		if (buffer->flags & EFX_TX_BUF_SKB)
+			finished = true;
+		efx_dequeue_buffer(tx_queue, buffer, &pkts_compl, &bytes_compl);
+
+		++tx_queue->read_count;
+		read_ptr = tx_queue->read_count & tx_queue->ptr_mask;
+	}
+
+	tx_queue->pkts_compl += pkts_compl;
+	tx_queue->bytes_compl += bytes_compl;
+
+	EFX_WARN_ON_PARANOID(pkts_compl != 1);
+
+	efx_xmit_done_check_empty(tx_queue);
+}
+
 void efx_init_tx_queue_core_txq(struct efx_tx_queue *tx_queue)
 {
 	struct efx_nic *efx = tx_queue->efx;

drivers/net/ethernet/sfc/tx_common.c

@@ -80,7 +80,6 @@ void efx_init_tx_queue(struct efx_tx_queue *tx_queue)
 	tx_queue->xmit_more_available = false;
 	tx_queue->timestamping = (efx_ptp_use_mac_tx_timestamps(efx) &&
 				  tx_queue->channel == efx_ptp_channel(efx));
-	tx_queue->completed_desc_ptr = tx_queue->ptr_mask;
 	tx_queue->completed_timestamp_major = 0;
 	tx_queue->completed_timestamp_minor = 0;
 
@@ -210,10 +209,9 @@ static void efx_dequeue_buffers(struct efx_tx_queue *tx_queue,
 	while (read_ptr != stop_index) {
 		struct efx_tx_buffer *buffer = &tx_queue->buffer[read_ptr];
 
-		if (!(buffer->flags & EFX_TX_BUF_OPTION) &&
-		    unlikely(buffer->len == 0)) {
+		if (!efx_tx_buffer_in_use(buffer)) {
 			netif_err(efx, tx_err, efx->net_dev,
-				  "TX queue %d spurious TX completion id %x\n",
+				  "TX queue %d spurious TX completion id %d\n",
 				  tx_queue->queue, read_ptr);
 			efx_schedule_reset(efx, RESET_TYPE_TX_SKIP);
 			return;
@@ -226,6 +224,19 @@ static void efx_dequeue_buffers(struct efx_tx_queue *tx_queue,
 	}
 }
 
+void efx_xmit_done_check_empty(struct efx_tx_queue *tx_queue)
+{
+	if ((int)(tx_queue->read_count - tx_queue->old_write_count) >= 0) {
+		tx_queue->old_write_count = READ_ONCE(tx_queue->write_count);
+		if (tx_queue->read_count == tx_queue->old_write_count) {
+			/* Ensure that read_count is flushed. */
+			smp_mb();
+			tx_queue->empty_read_count =
+				tx_queue->read_count | EFX_EMPTY_COUNT_VALID;
+		}
+	}
+}
+
 void efx_xmit_done(struct efx_tx_queue *tx_queue, unsigned int index)
 {
 	unsigned int fill_level, pkts_compl = 0, bytes_compl = 0;
@@ -256,15 +267,7 @@ void efx_xmit_done(struct efx_tx_queue *tx_queue, unsigned int index)
 			netif_tx_wake_queue(tx_queue->core_txq);
 	}
 
-	/* Check whether the hardware queue is now empty */
-	if ((int)(tx_queue->read_count - tx_queue->old_write_count) >= 0) {
-		tx_queue->old_write_count = READ_ONCE(tx_queue->write_count);
-		if (tx_queue->read_count == tx_queue->old_write_count) {
-			smp_mb();
-			tx_queue->empty_read_count =
-				tx_queue->read_count | EFX_EMPTY_COUNT_VALID;
-		}
-	}
+	efx_xmit_done_check_empty(tx_queue);
 }
 
 /* Remove buffers put into a tx_queue for the current packet.

drivers/net/ethernet/sfc/tx_common.h

@@ -21,6 +21,12 @@ void efx_dequeue_buffer(struct efx_tx_queue *tx_queue,
 			unsigned int *pkts_compl,
 			unsigned int *bytes_compl);
 
+static inline bool efx_tx_buffer_in_use(struct efx_tx_buffer *buffer)
+{
+	return buffer->len || (buffer->flags & EFX_TX_BUF_OPTION);
+}
+
+void efx_xmit_done_check_empty(struct efx_tx_queue *tx_queue);
 void efx_xmit_done(struct efx_tx_queue *tx_queue, unsigned int index);
 
 void efx_enqueue_unwind(struct efx_tx_queue *tx_queue,