[dpdk-dev] [PATCH v2 2/8] net/mlx5: prepare vector Rx ring at setup time

[Nelio Laranjeiro]

To use the vector, it needs to add to the PMD Rx mbuf ring four extra mbuf
to avoid memory corruption.  This additional mbuf are added on dev_start()
whereas all other mbuf are allocated on queue setup.

This patch brings this allocation back to the same place as other mbuf
allocation.

Signed-off-by: Nelio Laranjeiro <nelio.laranjeiro at 6wind.com>
Acked-by: Yongseok Koh <yskoh at mellanox.com>
---
 drivers/net/mlx5/mlx5_ethdev.c       |  1 -
 drivers/net/mlx5/mlx5_rxq.c          | 43 ++++++++++++++++++++++++++++--------
 drivers/net/mlx5/mlx5_rxtx.c         |  6 -----
 drivers/net/mlx5/mlx5_rxtx.h         |  1 -
 drivers/net/mlx5/mlx5_rxtx_vec_sse.c | 38 -------------------------------
 5 files changed, 34 insertions(+), 55 deletions(-)

diff --git a/drivers/net/mlx5/mlx5_ethdev.c b/drivers/net/mlx5/mlx5_ethdev.c
index b0eb3cd..014edc7 100644
--- a/drivers/net/mlx5/mlx5_ethdev.c
+++ b/drivers/net/mlx5/mlx5_ethdev.c
@@ -1540,7 +1540,6 @@ void
 priv_select_rx_function(struct priv *priv)
 {
 	if (priv_check_vec_rx_support(priv) > 0) {
-		priv_prep_vec_rx_function(priv);
 		priv->dev->rx_pkt_burst = mlx5_rx_burst_vec;
 		DEBUG("selected RX vectorized function");
 	} else {
diff --git a/drivers/net/mlx5/mlx5_rxq.c b/drivers/net/mlx5/mlx5_rxq.c
index 550e648..de54175 100644
--- a/drivers/net/mlx5/mlx5_rxq.c
+++ b/drivers/net/mlx5/mlx5_rxq.c
@@ -711,6 +711,27 @@ rxq_alloc_elts(struct rxq_ctrl *rxq_ctrl, unsigned int elts_n)
 		};
 		(*rxq_ctrl->rxq.elts)[i] = buf;
 	}
+	if (rxq_check_vec_support(&rxq_ctrl->rxq) > 0) {
+		struct rxq *rxq = &rxq_ctrl->rxq;
+		struct rte_mbuf *mbuf_init = &rxq->fake_mbuf;
+
+		assert(rxq->elts_n == rxq->cqe_n);
+		/* Initialize default rearm_data for vPMD. */
+		mbuf_init->data_off = RTE_PKTMBUF_HEADROOM;
+		rte_mbuf_refcnt_set(mbuf_init, 1);
+		mbuf_init->nb_segs = 1;
+		mbuf_init->port = rxq->port_id;
+		/*
+		 * prevent compiler reordering:
+		 * rearm_data covers previous fields.
+		 */
+		rte_compiler_barrier();
+		rxq->mbuf_initializer = *(uint64_t *)&mbuf_init->rearm_data;
+		/* Padding with a fake mbuf for vectorized Rx. */
+		for (i = 0; i < MLX5_VPMD_DESCS_PER_LOOP; ++i)
+			(*rxq->elts)[elts_n + i] = &rxq->fake_mbuf;
+		rxq->trim_elts = 1;
+	}
 	DEBUG("%p: allocated and configured %u segments (max %u packets)",
 	      (void *)rxq_ctrl, elts_n, elts_n / (1 << rxq_ctrl->rxq.sges_n));
 	assert(ret == 0);
@@ -791,9 +812,11 @@ rxq_setup(struct rxq_ctrl *tmpl)
 	struct ibv_cq *ibcq = tmpl->cq;
 	struct ibv_mlx5_cq_info cq_info;
 	struct mlx5_rwq *rwq = container_of(tmpl->wq, struct mlx5_rwq, wq);
-	struct rte_mbuf *(*elts)[1 << tmpl->rxq.elts_n] =
+	const uint16_t desc_n =
+		(1 << tmpl->rxq.elts_n) + tmpl->priv->rx_vec_en *
+		MLX5_VPMD_DESCS_PER_LOOP;
+	struct rte_mbuf *(*elts)[desc_n] =
 		rte_calloc_socket("RXQ", 1, sizeof(*elts), 0, tmpl->socket);
-
 	if (ibv_mlx5_exp_get_cq_info(ibcq, &cq_info)) {
 		ERROR("Unable to query CQ info. check your OFED.");
 		return ENOTSUP;
@@ -863,7 +886,9 @@ rxq_ctrl_setup(struct rte_eth_dev *dev, struct rxq_ctrl *rxq_ctrl,
 	} attr;
 	unsigned int mb_len = rte_pktmbuf_data_room_size(mp);
 	unsigned int cqe_n = desc - 1;
-	struct rte_mbuf *(*elts)[desc] = NULL;
+	const uint16_t desc_n =
+		desc + priv->rx_vec_en * MLX5_VPMD_DESCS_PER_LOOP;
+	struct rte_mbuf *(*elts)[desc_n] = NULL;
 	int ret = 0;
 
 	(void)conf; /* Thresholds configuration (ignored). */
@@ -1114,7 +1139,8 @@ mlx5_rx_queue_setup(struct rte_eth_dev *dev, uint16_t idx, uint16_t desc,
 	struct priv *priv = dev->data->dev_private;
 	struct rxq *rxq = (*priv->rxqs)[idx];
 	struct rxq_ctrl *rxq_ctrl = container_of(rxq, struct rxq_ctrl, rxq);
-	const uint16_t desc_pad = MLX5_VPMD_DESCS_PER_LOOP; /* For vPMD. */
+	const uint16_t desc_n =
+		desc + priv->rx_vec_en * MLX5_VPMD_DESCS_PER_LOOP;
 	int ret;
 
 	if (mlx5_is_secondary())
@@ -1147,9 +1173,8 @@ mlx5_rx_queue_setup(struct rte_eth_dev *dev, uint16_t idx, uint16_t desc,
 		/* Resize if rxq size is changed. */
 		if (rxq_ctrl->rxq.elts_n != log2above(desc)) {
 			rxq_ctrl = rte_realloc(rxq_ctrl,
-					       sizeof(*rxq_ctrl) +
-					       (desc + desc_pad) *
-						sizeof(struct rte_mbuf *),
+					       sizeof(*rxq_ctrl) + desc_n *
+					       sizeof(struct rte_mbuf *),
 					       RTE_CACHE_LINE_SIZE);
 			if (!rxq_ctrl) {
 				ERROR("%p: unable to reallocate queue index %u",
@@ -1160,8 +1185,8 @@ mlx5_rx_queue_setup(struct rte_eth_dev *dev, uint16_t idx, uint16_t desc,
 		}
 	} else {
 		rxq_ctrl = rte_calloc_socket("RXQ", 1, sizeof(*rxq_ctrl) +
-					     (desc + desc_pad) *
-					      sizeof(struct rte_mbuf *),
+					     desc_n *
+					     sizeof(struct rte_mbuf *),
 					     0, socket);
 		if (rxq_ctrl == NULL) {
 			ERROR("%p: unable to allocate queue index %u",
diff --git a/drivers/net/mlx5/mlx5_rxtx.c b/drivers/net/mlx5/mlx5_rxtx.c
index b07bcd1..e9c4502 100644
--- a/drivers/net/mlx5/mlx5_rxtx.c
+++ b/drivers/net/mlx5/mlx5_rxtx.c
@@ -2028,9 +2028,3 @@ priv_check_vec_rx_support(struct priv *priv)
 	(void)priv;
 	return -ENOTSUP;
 }
-
-void __attribute__((weak))
-priv_prep_vec_rx_function(struct priv *priv)
-{
-	(void)priv;
-}
diff --git a/drivers/net/mlx5/mlx5_rxtx.h b/drivers/net/mlx5/mlx5_rxtx.h
index 7de1d10..d85ea16 100644
--- a/drivers/net/mlx5/mlx5_rxtx.h
+++ b/drivers/net/mlx5/mlx5_rxtx.h
@@ -348,7 +348,6 @@ int priv_check_raw_vec_tx_support(struct priv *);
 int priv_check_vec_tx_support(struct priv *);
 int rxq_check_vec_support(struct rxq *);
 int priv_check_vec_rx_support(struct priv *);
-void priv_prep_vec_rx_function(struct priv *);
 uint16_t mlx5_tx_burst_raw_vec(void *, struct rte_mbuf **, uint16_t);
 uint16_t mlx5_tx_burst_vec(void *, struct rte_mbuf **, uint16_t);
 uint16_t mlx5_rx_burst_vec(void *, struct rte_mbuf **, uint16_t);
diff --git a/drivers/net/mlx5/mlx5_rxtx_vec_sse.c b/drivers/net/mlx5/mlx5_rxtx_vec_sse.c
index 8560f74..67f63c6 100644
--- a/drivers/net/mlx5/mlx5_rxtx_vec_sse.c
+++ b/drivers/net/mlx5/mlx5_rxtx_vec_sse.c
@@ -1377,41 +1377,3 @@ priv_check_vec_rx_support(struct priv *priv)
 		return -ENOTSUP;
 	return 1;
 }
-
-/**
- * Prepare for vectorized RX.
- *
- * @param priv
- *   Pointer to private structure.
- */
-void
-priv_prep_vec_rx_function(struct priv *priv)
-{
-	uint16_t i;
-
-	for (i = 0; i < priv->rxqs_n; ++i) {
-		struct rxq *rxq = (*priv->rxqs)[i];
-		struct rte_mbuf *mbuf_init = &rxq->fake_mbuf;
-		const uint16_t desc = 1 << rxq->elts_n;
-		int j;
-
-		assert(rxq->elts_n == rxq->cqe_n);
-		/* Initialize default rearm_data for vPMD. */
-		mbuf_init->data_off = RTE_PKTMBUF_HEADROOM;
-		rte_mbuf_refcnt_set(mbuf_init, 1);
-		mbuf_init->nb_segs = 1;
-		mbuf_init->port = rxq->port_id;
-		/*
-		 * prevent compiler reordering:
-		 * rearm_data covers previous fields.
-		 */
-		rte_compiler_barrier();
-		rxq->mbuf_initializer =
-			*(uint64_t *)&mbuf_init->rearm_data;
-		/* Padding with a fake mbuf for vectorized Rx. */
-		for (j = 0; j < MLX5_VPMD_DESCS_PER_LOOP; ++j)
-			(*rxq->elts)[desc + j] = &rxq->fake_mbuf;
-		/* Mark that it need to be cleaned up for rxq_alloc_elts(). */
-		rxq->trim_elts = 1;
-	}
-}
-- 
2.1.4