[dpdk-dev] [RFC 09/10] virtio: fix how states are handled during initialization

[Stephen Hemminger <stephen@networkplumber.org>]

[-- Attachment #1: virtio-state.patch --]
[-- Type: text/plain, Size: 3987 bytes --]

Change order of initialiazation to match Linux kernel.
Don't blow away control queue by doing reset when stopped.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>


---
 lib/librte_pmd_virtio/virtio_ethdev.c |   50 ++++++++++------------------------
 lib/librte_pmd_virtio/virtio_rxtx.c   |    2 +
 2 files changed, 18 insertions(+), 34 deletions(-)

--- a/lib/librte_pmd_virtio/virtio_ethdev.c	2014-08-25 19:00:11.062556360 -0700
+++ b/lib/librte_pmd_virtio/virtio_ethdev.c	2014-08-25 19:00:12.122562032 -0700
@@ -394,9 +394,11 @@ virtio_dev_cq_queue_setup(struct rte_eth
 static void
 virtio_dev_close(struct rte_eth_dev *dev)
 {
-	PMD_INIT_LOG(DEBUG, "virtio_dev_close");
+	struct virtio_hw *hw = dev->data->dev_private;
 
-	virtio_dev_stop(dev);
+	vtpci_irq_config(hw, VIRTIO_MSI_NO_VECTOR);
+	vtpci_reset(hw);
+	virtio_dev_free_mbufs(dev);
 }
 
 /*
@@ -811,6 +813,9 @@ eth_virtio_dev_init(__rte_unused struct
 	if (rte_eal_process_type() == RTE_PROC_SECONDARY)
 		return 0;
 
+	/* Tell the host we've noticed this device. */
+	vtpci_set_status(hw, VIRTIO_CONFIG_STATUS_ACK);
+
 	pci_dev = eth_dev->pci_dev;
 	if (virtio_resource_init(pci_dev) < 0)
 		return -1;
@@ -821,9 +826,6 @@ eth_virtio_dev_init(__rte_unused struct
 	/* Reset the device although not necessary at startup */
 	vtpci_reset(hw);
 
-	/* Tell the host we've noticed this device. */
-	vtpci_set_status(hw, VIRTIO_CONFIG_STATUS_ACK);
-
 	/* Tell the host we've known how to drive the device. */
 	vtpci_set_status(hw, VIRTIO_CONFIG_STATUS_DRIVER);
 	virtio_negotiate_features(hw);
@@ -912,6 +914,9 @@ eth_virtio_dev_init(__rte_unused struct
 	/* Setup interrupt callback  */
 	rte_intr_callback_register(&pci_dev->intr_handle,
 				   virtio_interrupt_handler, eth_dev);
+
+	virtio_dev_cq_start(eth_dev);
+
 	return 0;
 }
 
@@ -982,19 +987,8 @@ virtio_dev_configure(struct rte_eth_dev
 static int
 virtio_dev_start(struct rte_eth_dev *dev)
 {
-	uint16_t nb_queues, i;
 	struct virtio_hw *hw = dev->data->dev_private;
-
-	/* Tell the host we've noticed this device. */
-	vtpci_set_status(hw, VIRTIO_CONFIG_STATUS_ACK);
-
-	/* Tell the host we've known how to drive the device. */
-	vtpci_set_status(hw, VIRTIO_CONFIG_STATUS_DRIVER);
-
-	virtio_dev_cq_start(dev);
-
-	/* Do final configuration before rx/tx engine starts */
-	virtio_dev_rxtx_start(dev);
+	uint16_t nb_queues;
 
 	/* check if lsc interrupt feature is enabled */
 	if (dev->data->dev_conf.intr_conf.lsc) {
@@ -1024,18 +1018,8 @@ virtio_dev_start(struct rte_eth_dev *dev
 			return -EINVAL;
 	}
 
-	PMD_INIT_LOG(DEBUG, "nb_queues=%d", nb_queues);
-
-	for (i = 0; i < nb_queues; i++)
-		virtqueue_notify(dev->data->rx_queues[i]);
-
-	PMD_INIT_LOG(DEBUG, "Notified backend at initialization");
-
-	for (i = 0; i < dev->data->nb_rx_queues; i++)
-		VIRTQUEUE_DUMP((struct virtqueue *)dev->data->rx_queues[i]);
-
-	for (i = 0; i < dev->data->nb_tx_queues; i++)
-		VIRTQUEUE_DUMP((struct virtqueue *)dev->data->tx_queues[i]);
+	/* Do final configuration before rx/tx engine starts */
+	virtio_dev_rxtx_start(dev);
 
 	return 0;
 }
@@ -1089,12 +1073,10 @@ static void virtio_dev_free_mbufs(struct
 static void
 virtio_dev_stop(struct rte_eth_dev *dev)
 {
-	struct virtio_hw *hw = dev->data->dev_private;
+	if (dev->data->dev_conf.intr_conf.lsc)
+		rte_intr_disable(&dev->pci_dev->intr_handle);
 
-	/* reset the NIC */
-	vtpci_irq_config(hw, 0);
-	vtpci_reset(hw);
-	virtio_dev_free_mbufs(dev);
+	memset(&dev->data->dev_link, 0, sizeof(struct rte_eth_link));
 }
 
 static int
--- a/lib/librte_pmd_virtio/virtio_rxtx.c	2014-08-25 19:00:11.062556360 -0700
+++ b/lib/librte_pmd_virtio/virtio_rxtx.c	2014-08-25 19:00:11.062556360 -0700
@@ -350,6 +350,8 @@ virtio_dev_rxtx_start(struct rte_eth_dev
 	for (i = 0; i < dev->data->nb_rx_queues; i++) {
 		virtio_dev_vring_start(dev->data->rx_queues[i], VTNET_RQ);
 		VIRTQUEUE_DUMP((struct virtqueue *)dev->data->rx_queues[i]);
+
+		virtqueue_notify(dev->data->rx_queues[i]);
 	}
 
 	/* Start tx vring. */