1 files changed, 113 insertions, 37 deletions
diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c
index 84307bb7313e..491d942cefca 100644
--- a/drivers/net/ethernet/intel/igc/igc_main.c
+++ b/drivers/net/ethernet/intel/igc/igc_main.c
@@ -1092,7 +1092,8 @@ static int igc_init_empty_frame(struct igc_ring *ring,
 
 	dma = dma_map_single(ring->dev, skb->data, size, DMA_TO_DEVICE);
 	if (dma_mapping_error(ring->dev, dma)) {
-		netdev_err_once(ring->netdev, "Failed to map DMA for TX\n");
+		net_err_ratelimited("%s: DMA mapping error for empty frame\n",
+				    netdev_name(ring->netdev));
 		return -ENOMEM;
 	}
 
@@ -1108,20 +1109,12 @@ static int igc_init_empty_frame(struct igc_ring *ring,
 	return 0;
 }
 
-static int igc_init_tx_empty_descriptor(struct igc_ring *ring,
-					struct sk_buff *skb,
-					struct igc_tx_buffer *first)
+static void igc_init_tx_empty_descriptor(struct igc_ring *ring,
+					 struct sk_buff *skb,
+					 struct igc_tx_buffer *first)
 {
 	union igc_adv_tx_desc *desc;
 	u32 cmd_type, olinfo_status;
-	int err;
-
-	if (!igc_desc_unused(ring))
-		return -EBUSY;
-
-	err = igc_init_empty_frame(ring, first, skb);
-	if (err)
-		return err;
 
 	cmd_type = IGC_ADVTXD_DTYP_DATA | IGC_ADVTXD_DCMD_DEXT |
 		   IGC_ADVTXD_DCMD_IFCS | IGC_TXD_DCMD |
@@ -1140,8 +1133,6 @@ static int igc_init_tx_empty_descriptor(struct igc_ring *ring,
 	ring->next_to_use++;
 	if (ring->next_to_use == ring->count)
 		ring->next_to_use = 0;
-
-	return 0;
 }
 
 #define IGC_EMPTY_FRAME_SIZE 60
@@ -1567,6 +1558,40 @@ static bool igc_request_tx_tstamp(struct igc_adapter *adapter, struct sk_buff *s
 	return false;
 }
 
+static int igc_insert_empty_frame(struct igc_ring *tx_ring)
+{
+	struct igc_tx_buffer *empty_info;
+	struct sk_buff *empty_skb;
+	void *data;
+	int ret;
+
+	empty_info = &tx_ring->tx_buffer_info[tx_ring->next_to_use];
+	empty_skb = alloc_skb(IGC_EMPTY_FRAME_SIZE, GFP_ATOMIC);
+	if (unlikely(!empty_skb)) {
+		net_err_ratelimited("%s: skb alloc error for empty frame\n",
+				    netdev_name(tx_ring->netdev));
+		return -ENOMEM;
+	}
+
+	data = skb_put(empty_skb, IGC_EMPTY_FRAME_SIZE);
+	memset(data, 0, IGC_EMPTY_FRAME_SIZE);
+
+	/* Prepare DMA mapping and Tx buffer information */
+	ret = igc_init_empty_frame(tx_ring, empty_info, empty_skb);
+	if (unlikely(ret)) {
+		dev_kfree_skb_any(empty_skb);
+		return ret;
+	}
+
+	/* Prepare advanced context descriptor for empty packet */
+	igc_tx_ctxtdesc(tx_ring, 0, false, 0, 0, 0);
+
+	/* Prepare advanced data descriptor for empty packet */
+	igc_init_tx_empty_descriptor(tx_ring, empty_skb, empty_info);
+
+	return 0;
+}
+
 static netdev_tx_t igc_xmit_frame_ring(struct sk_buff *skb,
 				       struct igc_ring *tx_ring)
 {
@@ -1586,6 +1611,7 @@ static netdev_tx_t igc_xmit_frame_ring(struct sk_buff *skb,
 	 *	+ 1 desc for skb_headlen/IGC_MAX_DATA_PER_TXD,
 	 *	+ 2 desc gap to keep tail from touching head,
 	 *	+ 1 desc for context descriptor,
+	 *	+ 2 desc for inserting an empty packet for launch time,
 	 * otherwise try next time
 	 */
 	for (f = 0; f < skb_shinfo(skb)->nr_frags; f++)
@@ -1605,24 +1631,16 @@ static netdev_tx_t igc_xmit_frame_ring(struct sk_buff *skb,
 	launch_time = igc_tx_launchtime(tx_ring, txtime, &first_flag, &insert_empty);
 
 	if (insert_empty) {
-		struct igc_tx_buffer *empty_info;
-		struct sk_buff *empty;
-		void *data;
-
-		empty_info = &tx_ring->tx_buffer_info[tx_ring->next_to_use];
-		empty = alloc_skb(IGC_EMPTY_FRAME_SIZE, GFP_ATOMIC);
-		if (!empty)
-			goto done;
-
-		data = skb_put(empty, IGC_EMPTY_FRAME_SIZE);
-		memset(data, 0, IGC_EMPTY_FRAME_SIZE);
-
-		igc_tx_ctxtdesc(tx_ring, 0, false, 0, 0, 0);
-
-		if (igc_init_tx_empty_descriptor(tx_ring,
-						 empty,
-						 empty_info) < 0)
-			dev_kfree_skb_any(empty);
+		/* Reset the launch time if the required empty frame fails to
+		 * be inserted. However, this packet is not dropped, so it
+		 * "dirties" the current Qbv cycle. This ensures that the
+		 * upcoming packet, which is scheduled in the next Qbv cycle,
+		 * does not require an empty frame. This way, the launch time
+		 * continues to function correctly despite the current failure
+		 * to insert the empty frame.
+		 */
+		if (igc_insert_empty_frame(tx_ring))
+			launch_time = 0;
 	}
 
 done:
@@ -1650,7 +1668,8 @@ done:
 		if (igc_request_tx_tstamp(adapter, skb, &tstamp_flags)) {
 			skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
 			tx_flags |= IGC_TX_FLAGS_TSTAMP | tstamp_flags;
-			if (skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP_USE_CYCLES)
+			if (skb->sk &&
+			    READ_ONCE(skb->sk->sk_tsflags) & SOF_TIMESTAMPING_BIND_PHC)
 				tx_flags |= IGC_TX_FLAGS_TSTAMP_TIMER_1;
 		} else {
 			adapter->tx_hwtstamp_skipped++;
@@ -2953,9 +2972,48 @@ static u64 igc_xsk_fill_timestamp(void *_priv)
 	return *(u64 *)_priv;
 }
 
+static void igc_xsk_request_launch_time(u64 launch_time, void *_priv)
+{
+	struct igc_metadata_request *meta_req = _priv;
+	struct igc_ring *tx_ring = meta_req->tx_ring;
+	__le32 launch_time_offset;
+	bool insert_empty = false;
+	bool first_flag = false;
+	u16 used_desc = 0;
+
+	if (!tx_ring->launchtime_enable)
+		return;
+
+	launch_time_offset = igc_tx_launchtime(tx_ring,
+					       ns_to_ktime(launch_time),
+					       &first_flag, &insert_empty);
+	if (insert_empty) {
+		/* Disregard the launch time request if the required empty frame
+		 * fails to be inserted.
+		 */
+		if (igc_insert_empty_frame(tx_ring))
+			return;
+
+		meta_req->tx_buffer =
+			&tx_ring->tx_buffer_info[tx_ring->next_to_use];
+		/* Inserting an empty packet requires two descriptors:
+		 * one data descriptor and one context descriptor.
+		 */
+		used_desc += 2;
+	}
+
+	/* Use one context descriptor to specify launch time and first flag. */
+	igc_tx_ctxtdesc(tx_ring, launch_time_offset, first_flag, 0, 0, 0);
+	used_desc += 1;
+
+	/* Update the number of used descriptors in this request */
+	meta_req->used_desc += used_desc;
+}
+
 const struct xsk_tx_metadata_ops igc_xsk_tx_metadata_ops = {
 	.tmo_request_timestamp		= igc_xsk_request_timestamp,
 	.tmo_fill_timestamp		= igc_xsk_fill_timestamp,
+	.tmo_request_launch_time	= igc_xsk_request_launch_time,
 };
 
 static void igc_xdp_xmit_zc(struct igc_ring *ring)
@@ -2978,7 +3036,13 @@ static void igc_xdp_xmit_zc(struct igc_ring *ring)
 	ntu = ring->next_to_use;
 	budget = igc_desc_unused(ring);
 
-	while (xsk_tx_peek_desc(pool, &xdp_desc) && budget--) {
+	/* Packets with launch time require one data descriptor and one context
+	 * descriptor. When the launch time falls into the next Qbv cycle, we
+	 * may need to insert an empty packet, which requires two more
+	 * descriptors. Therefore, to be safe, we always ensure we have at least
+	 * 4 descriptors available.
+	 */
+	while (xsk_tx_peek_desc(pool, &xdp_desc) && budget >= 4) {
 		struct igc_metadata_request meta_req;
 		struct xsk_tx_metadata *meta = NULL;
 		struct igc_tx_buffer *bi;
@@ -2999,9 +3063,19 @@ static void igc_xdp_xmit_zc(struct igc_ring *ring)
 		meta_req.tx_ring = ring;
 		meta_req.tx_buffer = bi;
 		meta_req.meta = meta;
+		meta_req.used_desc = 0;
 		xsk_tx_metadata_request(meta, &igc_xsk_tx_metadata_ops,
 					&meta_req);
 
+		/* xsk_tx_metadata_request() may have updated next_to_use */
+		ntu = ring->next_to_use;
+
+		/* xsk_tx_metadata_request() may have updated Tx buffer info */
+		bi = meta_req.tx_buffer;
+
+		/* xsk_tx_metadata_request() may use a few descriptors */
+		budget -= meta_req.used_desc;
+
 		tx_desc = IGC_TX_DESC(ring, ntu);
 		tx_desc->read.cmd_type_len = cpu_to_le32(meta_req.cmd_type);
 		tx_desc->read.olinfo_status = cpu_to_le32(olinfo_status);
@@ -3019,9 +3093,11 @@ static void igc_xdp_xmit_zc(struct igc_ring *ring)
 		ntu++;
 		if (ntu == ring->count)
 			ntu = 0;
+
+		ring->next_to_use = ntu;
+		budget--;
 	}
 
-	ring->next_to_use = ntu;
 	if (tx_desc) {
 		igc_flush_tx_descriptors(ring);
 		xsk_tx_release(pool);
@@ -7090,8 +7166,8 @@ static int igc_probe(struct pci_dev *pdev,
 	INIT_WORK(&adapter->reset_task, igc_reset_task);
 	INIT_WORK(&adapter->watchdog_task, igc_watchdog_task);
 
-	hrtimer_init(&adapter->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
-	adapter->hrtimer.function = &igc_qbv_scheduling_timer;
+	hrtimer_setup(&adapter->hrtimer, &igc_qbv_scheduling_timer, CLOCK_MONOTONIC,
+		      HRTIMER_MODE_REL);
 
 	/* Initialize link properties that are user-changeable */
 	adapter->fc_autoneg = true;