[dpdk-dev] [PATCH v2] ethdev: Rename RX/TX enable queue field for queue start and stop

[Ouyang Changchun <changchun.ouyang@intel.com>]

Update comments for the field start_rx_per_q for better readability.
Rename the field name to rx_enable_queue for better readability too.
Accordingly Update its reference in sample vhost.

Signed-off-by: Changchun Ouyang <changchun.ouyang@intel.com>
---
 examples/vhost/main.c             |  4 ++--
 lib/librte_ether/rte_ethdev.h     | 16 ++++++++++++++--
 lib/librte_pmd_ixgbe/ixgbe_rxtx.c |  8 ++++----
 lib/librte_pmd_ixgbe/ixgbe_rxtx.h |  4 ++--
 4 files changed, 22 insertions(+), 10 deletions(-)

diff --git a/examples/vhost/main.c b/examples/vhost/main.c
index 193aa25..2eea431 100644
--- a/examples/vhost/main.c
+++ b/examples/vhost/main.c
@@ -2984,9 +2984,9 @@ MAIN(int argc, char *argv[])
 		char pool_name[RTE_MEMPOOL_NAMESIZE];
 		char ring_name[RTE_MEMPOOL_NAMESIZE];
 
-		rx_conf_default.start_rx_per_q = (uint8_t)zero_copy;
+		rx_conf_default.rx_enable_queue = (uint8_t)zero_copy;
 		rx_conf_default.rx_drop_en = 0;
-		tx_conf_default.start_tx_per_q = (uint8_t)zero_copy;
+		tx_conf_default.tx_enable_queue = (uint8_t)zero_copy;
 		nb_mbuf = num_rx_descriptor
 			+ num_switching_cores * MBUF_CACHE_SIZE_ZCP
 			+ num_switching_cores * MAX_PKT_BURST;
diff --git a/lib/librte_ether/rte_ethdev.h b/lib/librte_ether/rte_ethdev.h
index 50df654..ba439f6 100644
--- a/lib/librte_ether/rte_ethdev.h
+++ b/lib/librte_ether/rte_ethdev.h
@@ -604,7 +604,16 @@ struct rte_eth_rxconf {
 	struct rte_eth_thresh rx_thresh; /**< RX ring threshold registers. */
 	uint16_t rx_free_thresh; /**< Drives the freeing of RX descriptors. */
 	uint8_t rx_drop_en; /**< Drop packets if no descriptors are available. */
-	uint8_t start_rx_per_q; /**< start rx per queue. */
+	/**< If rx_enable_queue is true, rte_eth_dev_rx_queue_start should be
+		invocated to start RX for one queue after rte_eth_dev_start is
+		invocated, and rte_eth_dev_rx_queue_start instead of
+		rte_eth_dev_start is responsible for allocating mbuf from
+		mempool and setup the DMA physical address. It is useful in
+		such scenario: buffer address is not available at the point of
+		rte_eth_dev_start's invocating but available later, e.g. in
+		VHOST zero copy case, the buffer address used to setup DMA
+		address is available only after one VM(guest) startup. */
+	uint8_t rx_enable_queue;
 };
 
 #define ETH_TXQ_FLAGS_NOMULTSEGS 0x0001 /**< nb_segs=1 for all mbufs */
@@ -625,7 +634,10 @@ struct rte_eth_txconf {
 	uint16_t tx_rs_thresh; /**< Drives the setting of RS bit on TXDs. */
 	uint16_t tx_free_thresh; /**< Drives the freeing of TX buffers. */
 	uint32_t txq_flags; /**< Set flags for the Tx queue */
-	uint8_t start_tx_per_q; /**< start tx per queue. */
+	/**< If tx_enable_queue is true, rte_eth_dev_tx_queue_start must be
+		invocated to start TX for one queue after rte_eth_dev_start is
+		invocated. Refer to start_rx_per_q for the use case. */
+	uint8_t tx_enable_queue;
 };
 
 /**
diff --git a/lib/librte_pmd_ixgbe/ixgbe_rxtx.c b/lib/librte_pmd_ixgbe/ixgbe_rxtx.c
index dfc2076..2872fad 100644
--- a/lib/librte_pmd_ixgbe/ixgbe_rxtx.c
+++ b/lib/librte_pmd_ixgbe/ixgbe_rxtx.c
@@ -1846,7 +1846,7 @@ ixgbe_dev_tx_queue_setup(struct rte_eth_dev *dev,
 	txq->port_id = dev->data->port_id;
 	txq->txq_flags = tx_conf->txq_flags;
 	txq->ops = &def_txq_ops;
-	txq->start_tx_per_q = tx_conf->start_tx_per_q;
+	txq->tx_enable_queue = tx_conf->tx_enable_queue;
 
 	/*
 	 * Modification to set VFTDT for virtual function if vf is detected
@@ -2091,7 +2091,7 @@ ixgbe_dev_rx_queue_setup(struct rte_eth_dev *dev,
 	rxq->crc_len = (uint8_t) ((dev->data->dev_conf.rxmode.hw_strip_crc) ?
 							0 : ETHER_CRC_LEN);
 	rxq->drop_en = rx_conf->rx_drop_en;
-	rxq->start_rx_per_q = rx_conf->start_rx_per_q;
+	rxq->rx_enable_queue = rx_conf->rx_enable_queue;
 
 	/*
 	 * Allocate RX ring hardware descriptors. A memzone large enough to
@@ -3652,13 +3652,13 @@ ixgbe_dev_rxtx_start(struct rte_eth_dev *dev)
 
 	for (i = 0; i < dev->data->nb_tx_queues; i++) {
 		txq = dev->data->tx_queues[i];
-		if (!txq->start_tx_per_q)
+		if (!txq->tx_enable_queue)
 			ixgbe_dev_tx_queue_start(dev, i);
 	}
 
 	for (i = 0; i < dev->data->nb_rx_queues; i++) {
 		rxq = dev->data->rx_queues[i];
-		if (!rxq->start_rx_per_q)
+		if (!rxq->rx_enable_queue)
 			ixgbe_dev_rx_queue_start(dev, i);
 	}
 
diff --git a/lib/librte_pmd_ixgbe/ixgbe_rxtx.h b/lib/librte_pmd_ixgbe/ixgbe_rxtx.h
index 64c0695..d6d856e 100644
--- a/lib/librte_pmd_ixgbe/ixgbe_rxtx.h
+++ b/lib/librte_pmd_ixgbe/ixgbe_rxtx.h
@@ -135,7 +135,7 @@ struct igb_rx_queue {
 	uint8_t             port_id;  /**< Device port identifier. */
 	uint8_t             crc_len;  /**< 0 if CRC stripped, 4 otherwise. */
 	uint8_t             drop_en;  /**< If not 0, set SRRCTL.Drop_En. */
-	uint8_t             start_rx_per_q;
+	uint8_t             rx_enable_queue;
 #ifdef RTE_LIBRTE_IXGBE_RX_ALLOW_BULK_ALLOC
 	/** need to alloc dummy mbuf, for wraparound when scanning hw ring */
 	struct rte_mbuf fake_mbuf;
@@ -200,7 +200,7 @@ struct igb_tx_queue {
 	/** Hardware context0 history. */
 	struct ixgbe_advctx_info ctx_cache[IXGBE_CTX_NUM];
 	struct ixgbe_txq_ops *ops;          /**< txq ops */
-	uint8_t             start_tx_per_q;
+	uint8_t             tx_enable_queue;
 };
 
 struct ixgbe_txq_ops {
-- 
1.8.4.2