net/bnxt: support fast mbuf free

Add support for DEV_TX_OFFLOAD_MBUF_FAST_FREE to bnxt
vector mode transmit. This offload may be enabled
only when multi-segment transmit is not needed, all
transmitted mbufs for a given queue will be allocated
from the same pool, and all transmitted mbufs will
have a reference count of 1.

Signed-off-by: Lance Richardson <lance.richardson@broadcom.com>
Reviewed-by: Ajit Khaparde <ajit.khaparde@broadcom.com>

doc/guides/nics/features/bnxt.ini

@@ -8,6 +8,7 @@ Speed capabilities   = Y
 Link status          = Y
 Link status event    = Y
 Rx interrupt         = Y
+Fast mbuf free       = Y
 Queue start/stop     = Y
 Burst mode info      = Y
 MTU update           = Y

drivers/net/bnxt/bnxt_ethdev.c

@@ -920,7 +920,9 @@ static int bnxt_dev_info_get_op(struct rte_eth_dev *eth_dev,
 	dev_info->rx_offload_capa = BNXT_DEV_RX_OFFLOAD_SUPPORT;
 	if (bp->flags & BNXT_FLAG_PTP_SUPPORTED)
 		dev_info->rx_offload_capa |= DEV_RX_OFFLOAD_TIMESTAMP;
-	dev_info->tx_offload_capa = BNXT_DEV_TX_OFFLOAD_SUPPORT;
+	dev_info->tx_queue_offload_capa = DEV_TX_OFFLOAD_MBUF_FAST_FREE;
+	dev_info->tx_offload_capa = BNXT_DEV_TX_OFFLOAD_SUPPORT |
+				    dev_info->tx_queue_offload_capa;
 	dev_info->flow_type_rss_offloads = BNXT_ETH_RSS_SUPPORT;
 
 	dev_info->speed_capa = bnxt_get_speed_capabilities(bp);
@@ -1191,6 +1193,7 @@ bnxt_transmit_function(__rte_unused struct rte_eth_dev *eth_dev)
 {
 #if defined(RTE_ARCH_X86) || defined(RTE_ARCH_ARM64)
 #ifndef RTE_LIBRTE_IEEE1588
+	uint64_t offloads = eth_dev->data->dev_conf.txmode.offloads;
 	struct bnxt *bp = eth_dev->data->dev_private;
 
 	/*
@@ -1198,7 +1201,7 @@ bnxt_transmit_function(__rte_unused struct rte_eth_dev *eth_dev)
 	 * or tx offloads.
 	 */
 	if (!eth_dev->data->scattered_rx &&
-	    !eth_dev->data->dev_conf.txmode.offloads &&
+	    !(offloads & ~DEV_TX_OFFLOAD_MBUF_FAST_FREE) &&
 	    !BNXT_TRUFLOW_EN(bp)) {
 		PMD_DRV_LOG(INFO, "Using vector mode transmit for port %d\n",
 			    eth_dev->data->port_id);
@@ -1210,7 +1213,7 @@ bnxt_transmit_function(__rte_unused struct rte_eth_dev *eth_dev)
 		    "Port %d scatter: %d tx offload: %" PRIX64 "\n",
 		    eth_dev->data->port_id,
 		    eth_dev->data->scattered_rx,
-		    eth_dev->data->dev_conf.txmode.offloads);
+		    offloads);
 #endif
 #endif
 	return bnxt_xmit_pkts;
@@ -2685,7 +2688,7 @@ bnxt_txq_info_get_op(struct rte_eth_dev *dev, uint16_t queue_id,
 	qinfo->conf.tx_free_thresh = txq->tx_free_thresh;
 	qinfo->conf.tx_rs_thresh = 0;
 	qinfo->conf.tx_deferred_start = txq->tx_deferred_start;
-	qinfo->conf.offloads = dev->data->dev_conf.txmode.offloads;
+	qinfo->conf.offloads = txq->offloads;
 }
 
 static const struct {

drivers/net/bnxt/bnxt_rxtx_vec_common.h

@@ -94,4 +94,36 @@ bnxt_rxq_rearm(struct bnxt_rx_queue *rxq, struct bnxt_rx_ring_info *rxr)
 
 	rxq->rxrearm_nb -= nb;
 }
+
+static inline void
+bnxt_tx_cmp_vec(struct bnxt_tx_queue *txq, int nr_pkts)
+{
+	struct bnxt_tx_ring_info *txr = txq->tx_ring;
+	struct rte_mbuf **free = txq->free;
+	uint16_t cons = txr->tx_cons;
+	unsigned int blk = 0;
+	uint32_t ring_mask = txr->tx_ring_struct->ring_mask;
+
+	while (nr_pkts--) {
+		struct bnxt_sw_tx_bd *tx_buf;
+		struct rte_mbuf *mbuf;
+
+		tx_buf = &txr->tx_buf_ring[cons];
+		cons = (cons + 1) & ring_mask;
+		mbuf = rte_pktmbuf_prefree_seg(tx_buf->mbuf);
+		if (unlikely(mbuf == NULL))
+			continue;
+		tx_buf->mbuf = NULL;
+
+		if (blk && mbuf->pool != free[0]->pool) {
+			rte_mempool_put_bulk(free[0]->pool, (void **)free, blk);
+			blk = 0;
+		}
+		free[blk++] = mbuf;
+	}
+	if (blk)
+		rte_mempool_put_bulk(free[0]->pool, (void **)free, blk);
+
+	txr->tx_cons = cons;
+}
 #endif /* _BNXT_RXTX_VEC_COMMON_H_ */

drivers/net/bnxt/bnxt_rxtx_vec_neon.c

@@ -13,10 +13,10 @@
 #include "bnxt.h"
 #include "bnxt_cpr.h"
 #include "bnxt_ring.h"
-#include "bnxt_rxtx_vec_common.h"
 
 #include "bnxt_txq.h"
 #include "bnxt_txr.h"
+#include "bnxt_rxtx_vec_common.h"
 
 /*
  * RX Ring handling
@@ -338,37 +338,6 @@ out:
 	return nb_rx_pkts;
 }
 
-static void
-bnxt_tx_cmp_vec(struct bnxt_tx_queue *txq, int nr_pkts)
-{
-	struct bnxt_tx_ring_info *txr = txq->tx_ring;
-	struct rte_mbuf **free = txq->free;
-	uint16_t cons = txr->tx_cons;
-	unsigned int blk = 0;
-
-	while (nr_pkts--) {
-		struct bnxt_sw_tx_bd *tx_buf;
-		struct rte_mbuf *mbuf;
-
-		tx_buf = &txr->tx_buf_ring[cons];
-		cons = RING_NEXT(txr->tx_ring_struct, cons);
-		mbuf = rte_pktmbuf_prefree_seg(tx_buf->mbuf);
-		if (unlikely(mbuf == NULL))
-			continue;
-		tx_buf->mbuf = NULL;
-
-		if (blk && mbuf->pool != free[0]->pool) {
-			rte_mempool_put_bulk(free[0]->pool, (void **)free, blk);
-			blk = 0;
-		}
-		free[blk++] = mbuf;
-	}
-	if (blk)
-		rte_mempool_put_bulk(free[0]->pool, (void **)free, blk);
-
-	txr->tx_cons = cons;
-}
-
 static void
 bnxt_handle_tx_cp_vec(struct bnxt_tx_queue *txq)
 {
@@ -399,7 +368,10 @@ bnxt_handle_tx_cp_vec(struct bnxt_tx_queue *txq)
 
 	cpr->valid = !!(raw_cons & cp_ring_struct->ring_size);
 	if (nb_tx_pkts) {
-		bnxt_tx_cmp_vec(txq, nb_tx_pkts);
+		if (txq->offloads & DEV_TX_OFFLOAD_MBUF_FAST_FREE)
+			bnxt_tx_cmp_fast(txq, nb_tx_pkts);
+		else
+			bnxt_tx_cmp_vec(txq, nb_tx_pkts);
 		cpr->cp_raw_cons = raw_cons;
 		bnxt_db_cq(cpr);
 	}

drivers/net/bnxt/bnxt_rxtx_vec_sse.c

@@ -13,10 +13,10 @@
 #include "bnxt.h"
 #include "bnxt_cpr.h"
 #include "bnxt_ring.h"
-#include "bnxt_rxtx_vec_common.h"
 
 #include "bnxt_txq.h"
 #include "bnxt_txr.h"
+#include "bnxt_rxtx_vec_common.h"
 
 /*
  * RX Ring handling
@@ -309,38 +309,6 @@ out:
 	return nb_rx_pkts;
 }
 
-static void
-bnxt_tx_cmp_vec(struct bnxt_tx_queue *txq, int nr_pkts)
-{
-	struct bnxt_tx_ring_info *txr = txq->tx_ring;
-	struct rte_mbuf **free = txq->free;
-	uint16_t cons = txr->tx_cons;
-	unsigned int blk = 0;
-	uint32_t ring_mask = txr->tx_ring_struct->ring_mask;
-
-	while (nr_pkts--) {
-		struct bnxt_sw_tx_bd *tx_buf;
-		struct rte_mbuf *mbuf;
-
-		tx_buf = &txr->tx_buf_ring[cons];
-		cons = (cons + 1) & ring_mask;
-		mbuf = rte_pktmbuf_prefree_seg(tx_buf->mbuf);
-		if (unlikely(mbuf == NULL))
-			continue;
-		tx_buf->mbuf = NULL;
-
-		if (blk && mbuf->pool != free[0]->pool) {
-			rte_mempool_put_bulk(free[0]->pool, (void **)free, blk);
-			blk = 0;
-		}
-		free[blk++] = mbuf;
-	}
-	if (blk)
-		rte_mempool_put_bulk(free[0]->pool, (void **)free, blk);
-
-	txr->tx_cons = cons;
-}
-
 static void
 bnxt_handle_tx_cp_vec(struct bnxt_tx_queue *txq)
 {
@@ -371,7 +339,10 @@ bnxt_handle_tx_cp_vec(struct bnxt_tx_queue *txq)
 
 	cpr->valid = !!(raw_cons & cp_ring_struct->ring_size);
 	if (nb_tx_pkts) {
-		bnxt_tx_cmp_vec(txq, nb_tx_pkts);
+		if (txq->offloads & DEV_TX_OFFLOAD_MBUF_FAST_FREE)
+			bnxt_tx_cmp_fast(txq, nb_tx_pkts);
+		else
+			bnxt_tx_cmp_vec(txq, nb_tx_pkts);
 		cpr->cp_raw_cons = raw_cons;
 		bnxt_db_cq(cpr);
 	}

drivers/net/bnxt/bnxt_txq.c

@@ -131,6 +131,8 @@ int bnxt_tx_queue_setup_op(struct rte_eth_dev *eth_dev,
 	txq->nb_tx_desc = nb_desc;
 	txq->tx_free_thresh =
 		RTE_MIN(rte_align32pow2(nb_desc) / 4, RTE_BNXT_MAX_TX_BURST);
+	txq->offloads = eth_dev->data->dev_conf.txmode.offloads |
+			tx_conf->offloads;
 
 	txq->tx_deferred_start = tx_conf->tx_deferred_start;
 

drivers/net/bnxt/bnxt_txq.h

@@ -39,6 +39,7 @@ struct bnxt_tx_queue {
 	struct bnxt_cp_ring_info	*cp_ring;
 	const struct rte_memzone *mz;
 	struct rte_mbuf **free;
+	uint64_t offloads;
 };
 
 void bnxt_free_txq_stats(struct bnxt_tx_queue *txq);

drivers/net/bnxt/bnxt_txr.c

@@ -428,7 +428,10 @@ static int bnxt_handle_tx_cp(struct bnxt_tx_queue *txq)
 	} while (nb_tx_pkts < ring_mask);
 
 	if (nb_tx_pkts) {
-		bnxt_tx_cmp(txq, nb_tx_pkts);
+		if (txq->offloads & DEV_TX_OFFLOAD_MBUF_FAST_FREE)
+			bnxt_tx_cmp_fast(txq, nb_tx_pkts);
+		else
+			bnxt_tx_cmp(txq, nb_tx_pkts);
 		cpr->cp_raw_cons = raw_cons;
 		bnxt_db_cq(cpr);
 	}

drivers/net/bnxt/bnxt_txr.h

@@ -52,6 +52,33 @@ static inline uint32_t bnxt_tx_avail(struct bnxt_tx_queue *txq)
 		 bnxt_tx_bds_in_hw(txq)) - 1);
 }
 
+/*
+ * Transmit completion function for use when DEV_TX_OFFLOAD_MBUF_FAST_FREE
+ * is enabled.
+ */
+static inline void
+bnxt_tx_cmp_fast(struct bnxt_tx_queue *txq, int nr_pkts)
+{
+	struct bnxt_tx_ring_info *txr = txq->tx_ring;
+	uint32_t ring_mask = txr->tx_ring_struct->ring_mask;
+	struct rte_mbuf **free = txq->free;
+	uint16_t cons = txr->tx_cons;
+	unsigned int blk = 0;
+
+	while (nr_pkts--) {
+		struct bnxt_sw_tx_bd *tx_buf;
+
+		tx_buf = &txr->tx_buf_ring[cons];
+		cons = (cons + 1) & ring_mask;
+		free[blk++] = tx_buf->mbuf;
+		tx_buf->mbuf = NULL;
+	}
+	if (blk)
+		rte_mempool_put_bulk(free[0]->pool, (void **)free, blk);
+
+	txr->tx_cons = cons;
+}
+
 void bnxt_free_tx_rings(struct bnxt *bp);
 int bnxt_init_one_tx_ring(struct bnxt_tx_queue *txq);
 int bnxt_init_tx_ring_struct(struct bnxt_tx_queue *txq, unsigned int socket_id);