1 files changed, 105 insertions, 63 deletions

diff --git a/drivers/net/ethernet/intel/idpf/idpf_txrx.c b/drivers/net/ethernet/intel/idpf/idpf_txrx.c
index 76479c4f3fec..9844d01eaedb 100644
--- a/drivers/net/ethernet/intel/idpf/idpf_txrx.c
+++ b/drivers/net/ethernet/intel/idpf/idpf_txrx.c
@@ -12,8 +12,8 @@ struct idpf_tx_stash {
 	struct libeth_sqe buf;
 };
 
-#define idpf_tx_buf_compl_tag(buf)	(*(int *)&(buf)->priv)
-LIBETH_SQE_CHECK_PRIV(int);
+#define idpf_tx_buf_compl_tag(buf)	(*(u32 *)&(buf)->priv)
+LIBETH_SQE_CHECK_PRIV(u32);
 
 static bool idpf_chk_linearize(struct sk_buff *skb, unsigned int max_bufs,
 			       unsigned int count);
@@ -77,11 +77,13 @@ static void idpf_tx_buf_rel_all(struct idpf_tx_queue *txq)
 {
 	struct libeth_sq_napi_stats ss = { };
 	struct idpf_buf_lifo *buf_stack;
+	struct idpf_tx_stash *stash;
 	struct libeth_cq_pp cp = {
 		.dev	= txq->dev,
 		.ss	= &ss,
 	};
-	u16 i;
+	struct hlist_node *tmp;
+	u32 i, tag;
 
 	/* Buffers already cleared, nothing to do */
 	if (!txq->tx_buf)
@@ -101,6 +103,20 @@ static void idpf_tx_buf_rel_all(struct idpf_tx_queue *txq)
 	if (!buf_stack->bufs)
 		return;
 
+	/*
+	 * If a Tx timeout occurred, there are potentially still bufs in the
+	 * hash table, free them here.
+	 */
+	hash_for_each_safe(txq->stash->sched_buf_hash, tag, tmp, stash,
+			   hlist) {
+		if (!stash)
+			continue;
+
+		libeth_tx_complete(&stash->buf, &cp);
+		hash_del(&stash->hlist);
+		idpf_buf_lifo_push(buf_stack, stash);
+	}
+
 	for (i = 0; i < buf_stack->size; i++)
 		kfree(buf_stack->bufs[i]);
 
@@ -117,6 +133,7 @@ static void idpf_tx_buf_rel_all(struct idpf_tx_queue *txq)
 static void idpf_tx_desc_rel(struct idpf_tx_queue *txq)
 {
 	idpf_tx_buf_rel_all(txq);
+	netdev_tx_reset_subqueue(txq->netdev, txq->idx);
 
 	if (!txq->desc_ring)
 		return;
@@ -1661,16 +1678,14 @@ static void idpf_tx_clean_stashed_bufs(struct idpf_tx_queue *txq,
 	/* Buffer completion */
 	hash_for_each_possible_safe(txq->stash->sched_buf_hash, stash, tmp_buf,
 				    hlist, compl_tag) {
-		if (unlikely(idpf_tx_buf_compl_tag(&stash->buf) !=
-			     (int)compl_tag))
+		if (unlikely(idpf_tx_buf_compl_tag(&stash->buf) != compl_tag))
 			continue;
 
+		hash_del(&stash->hlist);
 		libeth_tx_complete(&stash->buf, &cp);
 
 		/* Push shadow buf back onto stack */
 		idpf_buf_lifo_push(&txq->stash->buf_stack, stash);
-
-		hash_del(&stash->hlist);
 	}
 }
 
@@ -1701,6 +1716,7 @@ static int idpf_stash_flow_sch_buffers(struct idpf_tx_queue *txq,
 	stash->buf.bytes = tx_buf->bytes;
 	stash->buf.packets = tx_buf->packets;
 	stash->buf.type = tx_buf->type;
+	stash->buf.nr_frags = tx_buf->nr_frags;
 	dma_unmap_addr_set(&stash->buf, dma, dma_unmap_addr(tx_buf, dma));
 	dma_unmap_len_set(&stash->buf, len, dma_unmap_len(tx_buf, len));
 	idpf_tx_buf_compl_tag(&stash->buf) = idpf_tx_buf_compl_tag(tx_buf);
@@ -1716,9 +1732,8 @@ static int idpf_stash_flow_sch_buffers(struct idpf_tx_queue *txq,
 
 #define idpf_tx_splitq_clean_bump_ntc(txq, ntc, desc, buf)	\
 do {								\
-	(ntc)++;						\
-	if (unlikely(!(ntc))) {					\
-		ntc -= (txq)->desc_count;			\
+	if (unlikely(++(ntc) == (txq)->desc_count)) {		\
+		ntc = 0;					\
 		buf = (txq)->tx_buf;				\
 		desc = &(txq)->flex_tx[0];			\
 	} else {						\
@@ -1742,59 +1757,66 @@ do {								\
  * Separate packet completion events will be reported on the completion queue,
  * and the buffers will be cleaned separately. The stats are not updated from
  * this function when using flow-based scheduling.
+ *
+ * Furthermore, in flow scheduling mode, check to make sure there are enough
+ * reserve buffers to stash the packet. If there are not, return early, which
+ * will leave next_to_clean pointing to the packet that failed to be stashed.
+ *
+ * Return: false in the scenario above, true otherwise.
  */
-static void idpf_tx_splitq_clean(struct idpf_tx_queue *tx_q, u16 end,
+static bool idpf_tx_splitq_clean(struct idpf_tx_queue *tx_q, u16 end,
 				 int napi_budget,
 				 struct libeth_sq_napi_stats *cleaned,
 				 bool descs_only)
 {
 	union idpf_tx_flex_desc *next_pending_desc = NULL;
 	union idpf_tx_flex_desc *tx_desc;
-	s16 ntc = tx_q->next_to_clean;
+	u32 ntc = tx_q->next_to_clean;
 	struct libeth_cq_pp cp = {
 		.dev	= tx_q->dev,
 		.ss	= cleaned,
 		.napi	= napi_budget,
 	};
 	struct idpf_tx_buf *tx_buf;
+	bool clean_complete = true;
 
 	tx_desc = &tx_q->flex_tx[ntc];
 	next_pending_desc = &tx_q->flex_tx[end];
 	tx_buf = &tx_q->tx_buf[ntc];
-	ntc -= tx_q->desc_count;
 
 	while (tx_desc != next_pending_desc) {
-		union idpf_tx_flex_desc *eop_desc;
+		u32 eop_idx;
 
 		/* If this entry in the ring was used as a context descriptor,
-		 * it's corresponding entry in the buffer ring will have an
-		 * invalid completion tag since no buffer was used.  We can
-		 * skip this descriptor since there is no buffer to clean.
+		 * it's corresponding entry in the buffer ring is reserved. We
+		 * can skip this descriptor since there is no buffer to clean.
 		 */
 		if (tx_buf->type <= LIBETH_SQE_CTX)
 			goto fetch_next_txq_desc;
 
-		eop_desc = &tx_q->flex_tx[tx_buf->rs_idx];
+		if (unlikely(tx_buf->type != LIBETH_SQE_SKB))
+			break;
+
+		eop_idx = tx_buf->rs_idx;
 
 		if (descs_only) {
-			if (idpf_stash_flow_sch_buffers(tx_q, tx_buf))
+			if (IDPF_TX_BUF_RSV_UNUSED(tx_q) < tx_buf->nr_frags) {
+				clean_complete = false;
 				goto tx_splitq_clean_out;
+			}
+
+			idpf_stash_flow_sch_buffers(tx_q, tx_buf);
 
-			while (tx_desc != eop_desc) {
+			while (ntc != eop_idx) {
 				idpf_tx_splitq_clean_bump_ntc(tx_q, ntc,
 							      tx_desc, tx_buf);
-
-				if (dma_unmap_len(tx_buf, len)) {
-					if (idpf_stash_flow_sch_buffers(tx_q,
-									tx_buf))
-						goto tx_splitq_clean_out;
-				}
+				idpf_stash_flow_sch_buffers(tx_q, tx_buf);
 			}
 		} else {
 			libeth_tx_complete(tx_buf, &cp);
 
 			/* unmap remaining buffers */
-			while (tx_desc != eop_desc) {
+			while (ntc != eop_idx) {
 				idpf_tx_splitq_clean_bump_ntc(tx_q, ntc,
 							      tx_desc, tx_buf);
 
@@ -1808,8 +1830,9 @@ fetch_next_txq_desc:
 	}
 
 tx_splitq_clean_out:
-	ntc += tx_q->desc_count;
 	tx_q->next_to_clean = ntc;
+
+	return clean_complete;
 }
 
 #define idpf_tx_clean_buf_ring_bump_ntc(txq, ntc, buf)	\
@@ -1840,48 +1863,63 @@ static bool idpf_tx_clean_buf_ring(struct idpf_tx_queue *txq, u16 compl_tag,
 {
 	u16 idx = compl_tag & txq->compl_tag_bufid_m;
 	struct idpf_tx_buf *tx_buf = NULL;
-	u16 ntc = txq->next_to_clean;
 	struct libeth_cq_pp cp = {
 		.dev	= txq->dev,
 		.ss	= cleaned,
 		.napi	= budget,
 	};
-	u16 num_descs_cleaned = 0;
-	u16 orig_idx = idx;
+	u16 ntc, orig_idx = idx;
 
 	tx_buf = &txq->tx_buf[idx];
-	if (unlikely(tx_buf->type <= LIBETH_SQE_CTX))
+
+	if (unlikely(tx_buf->type <= LIBETH_SQE_CTX ||
+		     idpf_tx_buf_compl_tag(tx_buf) != compl_tag))
 		return false;
 
-	while (idpf_tx_buf_compl_tag(tx_buf) == (int)compl_tag) {
+	if (tx_buf->type == LIBETH_SQE_SKB)
 		libeth_tx_complete(tx_buf, &cp);
 
-		num_descs_cleaned++;
+	idpf_tx_clean_buf_ring_bump_ntc(txq, idx, tx_buf);
+
+	while (idpf_tx_buf_compl_tag(tx_buf) == compl_tag) {
+		libeth_tx_complete(tx_buf, &cp);
 		idpf_tx_clean_buf_ring_bump_ntc(txq, idx, tx_buf);
 	}
 
-	/* If we didn't clean anything on the ring for this completion, there's
-	 * nothing more to do.
-	 */
-	if (unlikely(!num_descs_cleaned))
-		return false;
-
-	/* Otherwise, if we did clean a packet on the ring directly, it's safe
-	 * to assume that the descriptors starting from the original
-	 * next_to_clean up until the previously cleaned packet can be reused.
-	 * Therefore, we will go back in the ring and stash any buffers still
-	 * in the ring into the hash table to be cleaned later.
+	/*
+	 * It's possible the packet we just cleaned was an out of order
+	 * completion, which means we can stash the buffers starting from
+	 * the original next_to_clean and reuse the descriptors. We need
+	 * to compare the descriptor ring next_to_clean packet's "first" buffer
+	 * to the "first" buffer of the packet we just cleaned to determine if
+	 * this is the case. Howevever, next_to_clean can point to either a
+	 * reserved buffer that corresponds to a context descriptor used for the
+	 * next_to_clean packet (TSO packet) or the "first" buffer (single
+	 * packet). The orig_idx from the packet we just cleaned will always
+	 * point to the "first" buffer. If next_to_clean points to a reserved
+	 * buffer, let's bump ntc once and start the comparison from there.
 	 */
+	ntc = txq->next_to_clean;
 	tx_buf = &txq->tx_buf[ntc];
-	while (tx_buf != &txq->tx_buf[orig_idx]) {
-		idpf_stash_flow_sch_buffers(txq, tx_buf);
+
+	if (tx_buf->type == LIBETH_SQE_CTX)
 		idpf_tx_clean_buf_ring_bump_ntc(txq, ntc, tx_buf);
-	}
 
-	/* Finally, update next_to_clean to reflect the work that was just done
-	 * on the ring, if any. If the packet was only cleaned from the hash
-	 * table, the ring will not be impacted, therefore we should not touch
-	 * next_to_clean. The updated idx is used here
+	/*
+	 * If ntc still points to a different "first" buffer, clean the
+	 * descriptor ring and stash all of the buffers for later cleaning. If
+	 * we cannot stash all of the buffers, next_to_clean will point to the
+	 * "first" buffer of the packet that could not be stashed and cleaning
+	 * will start there next time.
+	 */
+	if (unlikely(tx_buf != &txq->tx_buf[orig_idx] &&
+		     !idpf_tx_splitq_clean(txq, orig_idx, budget, cleaned,
+					   true)))
+		return true;
+
+	/*
+	 * Otherwise, update next_to_clean to reflect the cleaning that was
+	 * done above.
 	 */
 	txq->next_to_clean = idx;
 
@@ -1909,7 +1947,8 @@ static void idpf_tx_handle_rs_completion(struct idpf_tx_queue *txq,
 	if (!idpf_queue_has(FLOW_SCH_EN, txq)) {
 		u16 head = le16_to_cpu(desc->q_head_compl_tag.q_head);
 
-		return idpf_tx_splitq_clean(txq, head, budget, cleaned, false);
+		idpf_tx_splitq_clean(txq, head, budget, cleaned, false);
+		return;
 	}
 
 	compl_tag = le16_to_cpu(desc->q_head_compl_tag.compl_tag);
@@ -2337,6 +2376,7 @@ static void idpf_tx_splitq_map(struct idpf_tx_queue *tx_q,
 	dma = dma_map_single(tx_q->dev, skb->data, size, DMA_TO_DEVICE);
 
 	tx_buf = first;
+	first->nr_frags = 0;
 
 	params->compl_tag =
 		(tx_q->compl_tag_cur_gen << tx_q->compl_tag_gen_s) | i;
@@ -2347,6 +2387,7 @@ static void idpf_tx_splitq_map(struct idpf_tx_queue *tx_q,
 		if (dma_mapping_error(tx_q->dev, dma))
 			return idpf_tx_dma_map_error(tx_q, skb, first, i);
 
+		first->nr_frags++;
 		idpf_tx_buf_compl_tag(tx_buf) = params->compl_tag;
 		tx_buf->type = LIBETH_SQE_FRAG;
 
@@ -2402,14 +2443,15 @@ static void idpf_tx_splitq_map(struct idpf_tx_queue *tx_q,
 			idpf_tx_splitq_build_desc(tx_desc, params, td_cmd,
 						  max_data);
 
-			tx_desc++;
-			i++;
-
-			if (i == tx_q->desc_count) {
+			if (unlikely(++i == tx_q->desc_count)) {
+				tx_buf = tx_q->tx_buf;
 				tx_desc = &tx_q->flex_tx[0];
 				i = 0;
 				tx_q->compl_tag_cur_gen =
 					IDPF_TX_ADJ_COMPL_TAG_GEN(tx_q);
+			} else {
+				tx_buf++;
+				tx_desc++;
 			}
 
 			/* Since this packet has a buffer that is going to span
@@ -2422,7 +2464,7 @@ static void idpf_tx_splitq_map(struct idpf_tx_queue *tx_q,
 			 * simply pass over these holes and finish cleaning the
 			 * rest of the packet.
 			 */
-			tx_q->tx_buf[i].type = LIBETH_SQE_EMPTY;
+			tx_buf->type = LIBETH_SQE_EMPTY;
 
 			/* Adjust the DMA offset and the remaining size of the
 			 * fragment.  On the first iteration of this loop,
@@ -2446,13 +2488,15 @@ static void idpf_tx_splitq_map(struct idpf_tx_queue *tx_q,
 			break;
 
 		idpf_tx_splitq_build_desc(tx_desc, params, td_cmd, size);
-		tx_desc++;
-		i++;
 
-		if (i == tx_q->desc_count) {
+		if (unlikely(++i == tx_q->desc_count)) {
+			tx_buf = tx_q->tx_buf;
 			tx_desc = &tx_q->flex_tx[0];
 			i = 0;
 			tx_q->compl_tag_cur_gen = IDPF_TX_ADJ_COMPL_TAG_GEN(tx_q);
+		} else {
+			tx_buf++;
+			tx_desc++;
 		}
 
 		size = skb_frag_size(frag);
@@ -2460,8 +2504,6 @@ static void idpf_tx_splitq_map(struct idpf_tx_queue *tx_q,
 
 		dma = skb_frag_dma_map(tx_q->dev, frag, 0, size,
 				       DMA_TO_DEVICE);
-
-		tx_buf = &tx_q->tx_buf[i];
 	}
 
 	/* record SW timestamp if HW timestamp is not available */