[dpdk-dev] [PATCH 2/2] net/virtio: support to turn on/off the traffic flow

[Zhiyong Yang]

virtio_dev_start/stop support the switch of traffic flow.

Signed-off-by: Zhiyong Yang <zhiyong.yang at intel.com>
---
 drivers/net/virtio/virtio_ethdev.c           | 37 +++++++++++++++++++++++++++-
 drivers/net/virtio/virtio_rxtx.c             | 12 +++++++++
 drivers/net/virtio/virtio_rxtx_simple.c      |  4 +++
 drivers/net/virtio/virtio_rxtx_simple_neon.c |  5 +++-
 drivers/net/virtio/virtio_rxtx_simple_sse.c  |  5 +++-
 drivers/net/virtio/virtio_user_ethdev.c      |  1 +
 6 files changed, 61 insertions(+), 3 deletions(-)

diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
index d9986ab..5955443 100644
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -1707,6 +1707,33 @@ virtio_dev_configure(struct rte_eth_dev *dev)
 	return 0;
 }
 
+static void
+update_queuing_status(struct rte_eth_dev *dev)
+{
+	struct virtio_hw *hw = dev->data->dev_private;
+	unsigned int i;
+	struct virtnet_rx *vnet_rx;
+	struct virtnet_tx *vnet_tx;
+	int allow_queuing = 1;
+
+	if (rte_atomic32_read(&hw->started) == 0)
+		allow_queuing = 0;
+
+	/* Wait until rx/tx_pkt_burst stops accessing virtio device */
+	for (i = 0; i < dev->data->nb_rx_queues; i++) {
+		vnet_rx = dev->data->rx_queues[i];
+		if (!vnet_rx)
+			continue;
+		rte_atomic32_set(&vnet_rx->allow_queuing, allow_queuing);
+	}
+
+	for (i = 0; i < dev->data->nb_tx_queues; i++) {
+		vnet_tx = dev->data->tx_queues[i];
+		if (!vnet_tx)
+			continue;
+		rte_atomic32_set(&vnet_tx->allow_queuing, allow_queuing);
+	}
+}
 
 static int
 virtio_dev_start(struct rte_eth_dev *dev)
@@ -1758,6 +1785,9 @@ virtio_dev_start(struct rte_eth_dev *dev)
 		virtqueue_notify(rxvq->vq);
 	}
 
+	rte_atomic32_set(&hw->started, 1);
+	update_queuing_status(dev);
+
 	PMD_INIT_LOG(DEBUG, "Notified backend at initialization");
 
 	for (i = 0; i < dev->data->nb_rx_queues; i++) {
@@ -1819,13 +1849,15 @@ static void virtio_dev_free_mbufs(struct rte_eth_dev *dev)
 }
 
 /*
- * Stop device: disable interrupt and mark link down
+ * Stop device: disable interrupt, mark link down
+ *              and stop the traffic flow.
  */
 static void
 virtio_dev_stop(struct rte_eth_dev *dev)
 {
 	struct rte_eth_link link;
 	struct rte_intr_conf *intr_conf = &dev->data->dev_conf.intr_conf;
+	struct virtio_hw *hw = dev->data->dev_private;
 
 	PMD_INIT_LOG(DEBUG, "stop");
 
@@ -1834,6 +1866,9 @@ virtio_dev_stop(struct rte_eth_dev *dev)
 
 	memset(&link, 0, sizeof(link));
 	virtio_dev_atomic_write_link_status(dev, &link);
+
+	rte_atomic32_set(&hw->started, 0);
+	update_queuing_status(dev);
 }
 
 static int
diff --git a/drivers/net/virtio/virtio_rxtx.c b/drivers/net/virtio/virtio_rxtx.c
index fcd9e93..3ef9678 100644
--- a/drivers/net/virtio/virtio_rxtx.c
+++ b/drivers/net/virtio/virtio_rxtx.c
@@ -736,6 +736,10 @@ virtio_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts, uint16_t nb_pkts)
 	int offload;
 	struct virtio_net_hdr *hdr;
 
+	nb_rx = 0;
+	if (unlikely(rte_atomic32_read(&rxvq->allow_queuing) == 0))
+		return nb_rx;
+
 	nb_used = VIRTQUEUE_NUSED(vq);
 
 	virtio_rmb();
@@ -850,6 +854,10 @@ virtio_recv_mergeable_pkts(void *rx_queue,
 	uint32_t hdr_size;
 	int offload;
 
+	nb_rx = 0;
+	if (unlikely(rte_atomic32_read(&rxvq->allow_queuing) == 0))
+		return nb_rx;
+
 	nb_used = VIRTQUEUE_NUSED(vq);
 
 	virtio_rmb();
@@ -1012,6 +1020,10 @@ virtio_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
 	uint16_t nb_used, nb_tx;
 	int error;
 
+	nb_tx = 0;
+	if (unlikely(rte_atomic32_read(&txvq->allow_queuing) == 0))
+		return nb_tx;
+
 	if (unlikely(nb_pkts < 1))
 		return nb_pkts;
 
diff --git a/drivers/net/virtio/virtio_rxtx_simple.c b/drivers/net/virtio/virtio_rxtx_simple.c
index b651e53..d061e72 100644
--- a/drivers/net/virtio/virtio_rxtx_simple.c
+++ b/drivers/net/virtio/virtio_rxtx_simple.c
@@ -95,6 +95,10 @@ virtio_xmit_pkts_simple(void *tx_queue, struct rte_mbuf **tx_pkts,
 	uint16_t nb_tail, nb_commit;
 	int i;
 	uint16_t desc_idx_max = (vq->vq_nentries >> 1) - 1;
+	uint16_t nb_tx = 0;
+
+	if (unlikely(rte_atomic32_read(&txvq->allow_queuing) == 0))
+		return nb_tx;
 
 	nb_used = VIRTQUEUE_NUSED(vq);
 	rte_compiler_barrier();
diff --git a/drivers/net/virtio/virtio_rxtx_simple_neon.c b/drivers/net/virtio/virtio_rxtx_simple_neon.c
index 793eefb..5aa7e2f 100644
--- a/drivers/net/virtio/virtio_rxtx_simple_neon.c
+++ b/drivers/net/virtio/virtio_rxtx_simple_neon.c
@@ -77,7 +77,7 @@ virtio_recv_pkts_vec(void *rx_queue, struct rte_mbuf **rx_pkts,
 	struct vring_used_elem *rused;
 	struct rte_mbuf **sw_ring;
 	struct rte_mbuf **sw_ring_end;
-	uint16_t nb_pkts_received;
+	uint16_t nb_pkts_received = 0;
 
 	uint8x16_t shuf_msk1 = {
 		0xFF, 0xFF, 0xFF, 0xFF, /* packet type */
@@ -106,6 +106,9 @@ virtio_recv_pkts_vec(void *rx_queue, struct rte_mbuf **rx_pkts,
 		0, 0
 	};
 
+	if (unlikely(rte_atomic32_read(&rxvq->allow_queuing) == 0))
+		return nb_pkts_received;
+
 	if (unlikely(nb_pkts < RTE_VIRTIO_DESC_PER_LOOP))
 		return 0;
 
diff --git a/drivers/net/virtio/virtio_rxtx_simple_sse.c b/drivers/net/virtio/virtio_rxtx_simple_sse.c
index 87bb5c6..39fe557 100644
--- a/drivers/net/virtio/virtio_rxtx_simple_sse.c
+++ b/drivers/net/virtio/virtio_rxtx_simple_sse.c
@@ -79,7 +79,7 @@ virtio_recv_pkts_vec(void *rx_queue, struct rte_mbuf **rx_pkts,
 	struct vring_used_elem *rused;
 	struct rte_mbuf **sw_ring;
 	struct rte_mbuf **sw_ring_end;
-	uint16_t nb_pkts_received;
+	uint16_t nb_pkts_received = 0;
 	__m128i shuf_msk1, shuf_msk2, len_adjust;
 
 	shuf_msk1 = _mm_set_epi8(
@@ -109,6 +109,9 @@ virtio_recv_pkts_vec(void *rx_queue, struct rte_mbuf **rx_pkts,
 		0, (uint16_t)-vq->hw->vtnet_hdr_size,
 		0, 0);
 
+	if (unlikely(rte_atomic32_read(&rxvq->allow_queuing) == 0))
+		return nb_pkts_received;
+
 	if (unlikely(nb_pkts < RTE_VIRTIO_DESC_PER_LOOP))
 		return 0;
 
diff --git a/drivers/net/virtio/virtio_user_ethdev.c b/drivers/net/virtio/virtio_user_ethdev.c
index d3a5cac..00b35e9 100644
--- a/drivers/net/virtio/virtio_user_ethdev.c
+++ b/drivers/net/virtio/virtio_user_ethdev.c
@@ -318,6 +318,7 @@ virtio_user_eth_dev_alloc(const char *name)
 	hw->modern   = 0;
 	hw->use_simple_rxtx = 0;
 	hw->virtio_user_dev = dev;
+	rte_atomic32_set(&hw->started, 0);
 	data->dev_private = hw;
 	data->drv_name = virtio_user_driver.driver.name;
 	data->numa_node = SOCKET_ID_ANY;
-- 
2.7.4