[PATCH v4 21/24] net/_common_intel: remove unneeded code

[Bruce Richardson <bruce.richardson@intel.com>]

With all drivers using the common Tx structure updated so that their
vector paths all use the simplified Tx mbuf ring format, it's no longer
necessary to have a separate flag for the ring format and for use of a
vector driver.

Remove the former flag and base all decisions off the vector flag. With
that done, we go from having only two paths to consider for releasing
all mbufs in the ring, not three. That allows further simplification of
the "ci_txq_release_all_mbufs" function.

The separate function to free buffers from the vector driver not using
the simplified ring format can similarly be removed as no longer
necessary.

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
---
 drivers/net/_common_intel/tx.h            | 97 +++--------------------
 drivers/net/i40e/i40e_rxtx.c              |  1 -
 drivers/net/iavf/iavf_rxtx_vec_sse.c      |  1 -
 drivers/net/ice/ice_rxtx.c                |  1 -
 drivers/net/ixgbe/ixgbe_rxtx_vec_common.h |  1 -
 5 files changed, 10 insertions(+), 91 deletions(-)

diff --git a/drivers/net/_common_intel/tx.h b/drivers/net/_common_intel/tx.h
index aa42b9b49f..d9cf4474fc 100644
--- a/drivers/net/_common_intel/tx.h
+++ b/drivers/net/_common_intel/tx.h
@@ -66,7 +66,6 @@ struct ci_tx_queue {
 	bool tx_deferred_start; /* don't start this queue in dev start */
 	bool q_set;             /* indicate if tx queue has been configured */
 	bool vector_tx;         /* port is using vector TX */
-	bool vector_sw_ring;    /* port is using vectorized SW ring (ieth_tx_entry_vec) */
 	union {                  /* the VSI this queue belongs to */
 		struct i40e_vsi *i40e_vsi;
 		struct iavf_vsi *iavf_vsi;
@@ -120,72 +119,6 @@ ci_tx_backlog_entry_vec(struct ci_tx_entry_vec *txep, struct rte_mbuf **tx_pkts,
 
 typedef int (*ci_desc_done_fn)(struct ci_tx_queue *txq, uint16_t idx);
 
-static __rte_always_inline int
-ci_tx_free_bufs(struct ci_tx_queue *txq, ci_desc_done_fn desc_done)
-{
-	struct ci_tx_entry *txep;
-	uint32_t n;
-	uint32_t i;
-	int nb_free = 0;
-	struct rte_mbuf *m, *free[IETH_VPMD_TX_MAX_FREE_BUF];
-
-	/* check DD bits on threshold descriptor */
-	if (!desc_done(txq, txq->tx_next_dd))
-		return 0;
-
-	n = txq->tx_rs_thresh;
-
-	 /* first buffer to free from S/W ring is at index
-	  * tx_next_dd - (tx_rs_thresh-1)
-	  */
-	txep = &txq->sw_ring[txq->tx_next_dd - (n - 1)];
-
-	if (txq->offloads & RTE_ETH_TX_OFFLOAD_MBUF_FAST_FREE) {
-		for (i = 0; i < n; i++) {
-			free[i] = txep[i].mbuf;
-			/* no need to reset txep[i].mbuf in vector path */
-		}
-		rte_mempool_put_bulk(free[0]->pool, (void **)free, n);
-		goto done;
-	}
-
-	m = rte_pktmbuf_prefree_seg(txep[0].mbuf);
-	if (likely(m != NULL)) {
-		free[0] = m;
-		nb_free = 1;
-		for (i = 1; i < n; i++) {
-			m = rte_pktmbuf_prefree_seg(txep[i].mbuf);
-			if (likely(m != NULL)) {
-				if (likely(m->pool == free[0]->pool)) {
-					free[nb_free++] = m;
-				} else {
-					rte_mempool_put_bulk(free[0]->pool,
-							     (void *)free,
-							     nb_free);
-					free[0] = m;
-					nb_free = 1;
-				}
-			}
-		}
-		rte_mempool_put_bulk(free[0]->pool, (void **)free, nb_free);
-	} else {
-		for (i = 1; i < n; i++) {
-			m = rte_pktmbuf_prefree_seg(txep[i].mbuf);
-			if (m != NULL)
-				rte_mempool_put(m->pool, m);
-		}
-	}
-
-done:
-	/* buffers were freed, update counters */
-	txq->nb_tx_free = (uint16_t)(txq->nb_tx_free + txq->tx_rs_thresh);
-	txq->tx_next_dd = (uint16_t)(txq->tx_next_dd + txq->tx_rs_thresh);
-	if (txq->tx_next_dd >= txq->nb_tx_desc)
-		txq->tx_next_dd = (uint16_t)(txq->tx_rs_thresh - 1);
-
-	return txq->tx_rs_thresh;
-}
-
 static __rte_always_inline int
 ci_tx_free_bufs_vec(struct ci_tx_queue *txq, ci_desc_done_fn desc_done, bool ctx_descs)
 {
@@ -278,21 +211,6 @@ ci_tx_free_bufs_vec(struct ci_tx_queue *txq, ci_desc_done_fn desc_done, bool ctx
 	return txq->tx_rs_thresh;
 }
 
-#define IETH_FREE_BUFS_LOOP(swr, nb_desc, start, end) do { \
-		uint16_t i = start; \
-		if (end < i) { \
-			for (; i < nb_desc; i++) { \
-				rte_pktmbuf_free_seg(swr[i].mbuf); \
-				swr[i].mbuf = NULL; \
-			} \
-			i = 0; \
-		} \
-		for (; i < end; i++) { \
-			rte_pktmbuf_free_seg(swr[i].mbuf); \
-			swr[i].mbuf = NULL; \
-		} \
-} while (0)
-
 static inline void
 ci_txq_release_all_mbufs(struct ci_tx_queue *txq, bool use_ctx)
 {
@@ -311,16 +229,21 @@ ci_txq_release_all_mbufs(struct ci_tx_queue *txq, bool use_ctx)
 
 	/**
 	 *  vPMD tx will not set sw_ring's mbuf to NULL after free,
-	 *  so need to free remains more carefully.
+	 *  so determining buffers to free is a little more complex.
 	 */
 	const uint16_t start = (txq->tx_next_dd - txq->tx_rs_thresh + 1) >> use_ctx;
 	const uint16_t nb_desc = txq->nb_tx_desc >> use_ctx;
 	const uint16_t end = txq->tx_tail >> use_ctx;
 
-	if (txq->vector_sw_ring)
-		IETH_FREE_BUFS_LOOP(txq->sw_ring_vec, nb_desc, start, end);
-	else
-		IETH_FREE_BUFS_LOOP(txq->sw_ring, nb_desc, start, end);
+	uint16_t i = start;
+	if (end < i) {
+		for (; i < nb_desc; i++)
+			rte_pktmbuf_free_seg(txq->sw_ring_vec[i].mbuf);
+		i = 0;
+	}
+	for (; i < end; i++)
+		rte_pktmbuf_free_seg(txq->sw_ring_vec[i].mbuf);
+	memset(txq->sw_ring_vec, 0, sizeof(txq->sw_ring_vec[0]) * nb_desc);
 }
 
 #endif /* _COMMON_INTEL_TX_H_ */
diff --git a/drivers/net/i40e/i40e_rxtx.c b/drivers/net/i40e/i40e_rxtx.c
index 745c467912..c3ff2e05c3 100644
--- a/drivers/net/i40e/i40e_rxtx.c
+++ b/drivers/net/i40e/i40e_rxtx.c
@@ -1891,7 +1891,6 @@ i40e_dev_tx_queue_start(struct rte_eth_dev *dev, uint16_t tx_queue_id)
 			    tx_queue_id);
 
 	txq->vector_tx = ad->tx_vec_allowed;
-	txq->vector_sw_ring = txq->vector_tx;
 
 	/*
 	 * tx_queue_id is queue id application refers to, while
diff --git a/drivers/net/iavf/iavf_rxtx_vec_sse.c b/drivers/net/iavf/iavf_rxtx_vec_sse.c
index 9f7db80bfd..21d5bfd309 100644
--- a/drivers/net/iavf/iavf_rxtx_vec_sse.c
+++ b/drivers/net/iavf/iavf_rxtx_vec_sse.c
@@ -1462,7 +1462,6 @@ int __rte_cold
 iavf_txq_vec_setup(struct ci_tx_queue *txq)
 {
 	txq->vector_tx = true;
-	txq->vector_sw_ring = txq->vector_tx;
 	return 0;
 }
 
diff --git a/drivers/net/ice/ice_rxtx.c b/drivers/net/ice/ice_rxtx.c
index 77cb6688a7..dcfa409813 100644
--- a/drivers/net/ice/ice_rxtx.c
+++ b/drivers/net/ice/ice_rxtx.c
@@ -825,7 +825,6 @@ ice_tx_queue_start(struct rte_eth_dev *dev, uint16_t tx_queue_id)
 
 	/* record what kind of descriptor cleanup we need on teardown */
 	txq->vector_tx = ad->tx_vec_allowed;
-	txq->vector_sw_ring = txq->vector_tx;
 
 	dev->data->tx_queue_state[tx_queue_id] = RTE_ETH_QUEUE_STATE_STARTED;
 
diff --git a/drivers/net/ixgbe/ixgbe_rxtx_vec_common.h b/drivers/net/ixgbe/ixgbe_rxtx_vec_common.h
index 2b12bdcc9c..53d1fed6f8 100644
--- a/drivers/net/ixgbe/ixgbe_rxtx_vec_common.h
+++ b/drivers/net/ixgbe/ixgbe_rxtx_vec_common.h
@@ -182,7 +182,6 @@ ixgbe_txq_vec_setup_default(struct ci_tx_queue *txq,
 	txq->sw_ring_vec = txq->sw_ring_vec + 1;
 	txq->ops = txq_ops;
 	txq->vector_tx = 1;
-	txq->vector_sw_ring = 1;
 
 	return 0;
 }
-- 
2.43.0