[dpdk-dev] [PATCH 4/8] ixgbe: implement device reset on VF

[Wenzhuo Lu]

Implement the device reset function.
1, Add the fake RX/TX functions.
2, The reset function tries to stop RX/TX by replacing
   the RX/TX functions with the fake ones and getting the
   locks to make sure the regular RX/TX finished.
3, After the RX/TX stopped, reset the VF port, and then
   release the locks and restore the RX/TX functions.

Signed-off-by: Wenzhuo Lu <wenzhuo.lu at intel.com>
---
 doc/guides/rel_notes/release_16_07.rst |   9 +++
 drivers/net/ixgbe/ixgbe_ethdev.c       | 108 ++++++++++++++++++++++++++++++++-
 drivers/net/ixgbe/ixgbe_ethdev.h       |  12 +++-
 drivers/net/ixgbe/ixgbe_rxtx.c         |  42 ++++++++++++-
 4 files changed, 168 insertions(+), 3 deletions(-)

diff --git a/doc/guides/rel_notes/release_16_07.rst b/doc/guides/rel_notes/release_16_07.rst
index a761e3c..d36c4b1 100644
--- a/doc/guides/rel_notes/release_16_07.rst
+++ b/doc/guides/rel_notes/release_16_07.rst
@@ -53,6 +53,15 @@ New Features
   VF. To handle this link up/down event, add the mailbox interruption
   support to receive the message.
 
+* **Added device reset support for ixgbe VF.**
+
+  Added the device reset API. APP can call this API to reset the VF port
+  when it's not working.
+  Based on the mailbox interruption support, when VF reseives the control
+  message from PF, it means the PF link state changes, VF uses the reset
+  callback in the message handler to notice the APP. APP need call the device
+  reset API to reset the VF port.
+
 
 Resolved Issues
 ---------------
diff --git a/drivers/net/ixgbe/ixgbe_ethdev.c b/drivers/net/ixgbe/ixgbe_ethdev.c
index fd2682f..1e3520b 100644
--- a/drivers/net/ixgbe/ixgbe_ethdev.c
+++ b/drivers/net/ixgbe/ixgbe_ethdev.c
@@ -381,6 +381,8 @@ static int ixgbe_dev_udp_tunnel_port_add(struct rte_eth_dev *dev,
 static int ixgbe_dev_udp_tunnel_port_del(struct rte_eth_dev *dev,
 					 struct rte_eth_udp_tunnel *udp_tunnel);
 
+static int ixgbevf_dev_reset(struct rte_eth_dev *dev);
+
 /*
  * Define VF Stats MACRO for Non "cleared on read" register
  */
@@ -586,6 +588,7 @@ static const struct eth_dev_ops ixgbevf_eth_dev_ops = {
 	.reta_query           = ixgbe_dev_rss_reta_query,
 	.rss_hash_update      = ixgbe_dev_rss_hash_update,
 	.rss_hash_conf_get    = ixgbe_dev_rss_hash_conf_get,
+	.dev_reset            = ixgbevf_dev_reset,
 };
 
 /* store statistics names and its offset in stats structure */
@@ -4060,7 +4063,8 @@ ixgbevf_dev_start(struct rte_eth_dev *dev)
 		ETH_VLAN_EXTEND_MASK;
 	ixgbevf_vlan_offload_set(dev, mask);
 
-	ixgbevf_dev_rxtx_start(dev);
+	if (ixgbevf_dev_rxtx_start(dev))
+		return -1;
 
 	/* check and configure queue intr-vector mapping */
 	if (dev->data->dev_conf.intr_conf.rxq != 0) {
@@ -7193,6 +7197,108 @@ static void ixgbevf_mbx_process(struct rte_eth_dev *dev)
 }
 
 static int
+ixgbevf_dev_reset(struct rte_eth_dev *dev)
+{
+	struct ixgbe_hw *hw = IXGBE_DEV_PRIVATE_TO_HW(dev->data->dev_private);
+	struct ixgbe_adapter *adapter =
+		(struct ixgbe_adapter *)dev->data->dev_private;
+	int diag = 0;
+	uint32_t vteiam;
+	uint16_t i;
+	struct ixgbe_rx_queue *rxq;
+	struct ixgbe_tx_queue *txq;
+
+	/* Nothing needs to be done if the device is not started. */
+	if (!dev->data->dev_started)
+		return 0;
+
+	PMD_DRV_LOG(DEBUG, "Link up/down event detected.");
+
+	/**
+	 * Stop RX/TX by fake functions and locks.
+	 * Fake functions are used to make RX/TX lock easier.
+	 */
+	adapter->rx_backup = dev->rx_pkt_burst;
+	adapter->tx_backup = dev->tx_pkt_burst;
+	dev->rx_pkt_burst = ixgbevf_recv_pkts_fake;
+	dev->tx_pkt_burst = ixgbevf_xmit_pkts_fake;
+
+	if (dev->data->rx_queues)
+		for (i = 0; i < dev->data->nb_rx_queues; i++) {
+			rxq = dev->data->rx_queues[i];
+			rte_spinlock_lock(&rxq->rx_lock);
+		}
+
+	if (dev->data->tx_queues)
+		for (i = 0; i < dev->data->nb_tx_queues; i++) {
+			txq = dev->data->tx_queues[i];
+			rte_spinlock_lock(&txq->tx_lock);
+		}
+
+	/* Performance VF reset. */
+	do {
+		dev->data->dev_started = 0;
+		ixgbevf_dev_stop(dev);
+		if (dev->data->dev_conf.intr_conf.lsc == 0)
+			diag = ixgbe_dev_link_update(dev, 0);
+		if (diag) {
+			PMD_INIT_LOG(INFO, "Ixgbe VF reset: "
+				     "Failed to update link.");
+		}
+		rte_delay_ms(1000);
+
+		diag = ixgbevf_dev_start(dev);
+		/*If fail to start the device, need to stop/start it again. */
+		if (diag) {
+			PMD_INIT_LOG(ERR, "Ixgbe VF reset: "
+				     "Failed to start device.");
+			continue;
+		}
+		dev->data->dev_started = 1;
+		ixgbevf_dev_stats_reset(dev);
+		if (dev->data->dev_conf.intr_conf.lsc == 0)
+			diag = ixgbe_dev_link_update(dev, 0);
+		if (diag) {
+			PMD_INIT_LOG(INFO, "Ixgbe VF reset: "
+				     "Failed to update link.");
+			diag = 0;
+		}
+
+		/**
+		 * When the PF link is down, there has chance
+		 * that VF cannot operate its registers. Will
+		 * check if the registers is written
+		 * successfully. If not, repeat stop/start until
+		 * the PF link is up, in other words, until the
+		 * registers can be written.
+		 */
+		vteiam = IXGBE_READ_REG(hw, IXGBE_VTEIAM);
+	/* Reference ixgbevf_intr_enable when checking */
+	} while (diag || vteiam != IXGBE_VF_IRQ_ENABLE_MASK);
+
+	/**
+	 * Release the locks for queues.
+	 * Restore the RX/TX functions.
+	 */
+	if (dev->data->rx_queues)
+		for (i = 0; i < dev->data->nb_rx_queues; i++) {
+			rxq = dev->data->rx_queues[i];
+			rte_spinlock_unlock(&rxq->rx_lock);
+		}
+
+	if (dev->data->tx_queues)
+		for (i = 0; i < dev->data->nb_tx_queues; i++) {
+			txq = dev->data->tx_queues[i];
+			rte_spinlock_unlock(&txq->tx_lock);
+		}
+
+	dev->rx_pkt_burst = adapter->rx_backup;
+	dev->tx_pkt_burst = adapter->tx_backup;
+
+	return 0;
+}
+
+static int
 ixgbevf_dev_interrupt_get_status(struct rte_eth_dev *dev)
 {
 	uint32_t eicr;
diff --git a/drivers/net/ixgbe/ixgbe_ethdev.h b/drivers/net/ixgbe/ixgbe_ethdev.h
index 701107b..d50fad4 100644
--- a/drivers/net/ixgbe/ixgbe_ethdev.h
+++ b/drivers/net/ixgbe/ixgbe_ethdev.h
@@ -289,6 +289,8 @@ struct ixgbe_adapter {
 	struct rte_timecounter      systime_tc;
 	struct rte_timecounter      rx_tstamp_tc;
 	struct rte_timecounter      tx_tstamp_tc;
+	eth_rx_burst_t              rx_backup;
+	eth_tx_burst_t              tx_backup;
 };
 
 #define IXGBE_DEV_PRIVATE_TO_HW(adapter)\
@@ -377,7 +379,7 @@ int ixgbevf_dev_rx_init(struct rte_eth_dev *dev);
 
 void ixgbevf_dev_tx_init(struct rte_eth_dev *dev);
 
-void ixgbevf_dev_rxtx_start(struct rte_eth_dev *dev);
+int ixgbevf_dev_rxtx_start(struct rte_eth_dev *dev);
 
 uint16_t ixgbe_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
 		uint16_t nb_pkts);
@@ -409,6 +411,14 @@ uint16_t ixgbe_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
 uint16_t ixgbe_xmit_pkts_simple(void *tx_queue, struct rte_mbuf **tx_pkts,
 		uint16_t nb_pkts);
 
+uint16_t ixgbevf_recv_pkts_fake(void *rx_queue,
+				struct rte_mbuf **rx_pkts,
+				uint16_t nb_pkts);
+
+uint16_t ixgbevf_xmit_pkts_fake(void *tx_queue,
+				struct rte_mbuf **tx_pkts,
+				uint16_t nb_pkts);
+
 uint16_t ixgbe_xmit_pkts_lock(void *tx_queue,
 			      struct rte_mbuf **tx_pkts,
 			      uint16_t nb_pkts);
diff --git a/drivers/net/ixgbe/ixgbe_rxtx.c b/drivers/net/ixgbe/ixgbe_rxtx.c
index a45d115..b4e7659 100644
--- a/drivers/net/ixgbe/ixgbe_rxtx.c
+++ b/drivers/net/ixgbe/ixgbe_rxtx.c
@@ -5181,7 +5181,7 @@ ixgbevf_dev_tx_init(struct rte_eth_dev *dev)
 /*
  * [VF] Start Transmit and Receive Units.
  */
-void __attribute__((cold))
+int __attribute__((cold))
 ixgbevf_dev_rxtx_start(struct rte_eth_dev *dev)
 {
 	struct ixgbe_hw     *hw;
@@ -5218,7 +5218,15 @@ ixgbevf_dev_rxtx_start(struct rte_eth_dev *dev)
 			txdctl = IXGBE_READ_REG(hw, IXGBE_VFTXDCTL(i));
 		} while (--poll_ms && !(txdctl & IXGBE_TXDCTL_ENABLE));
 		if (!poll_ms)
+#ifndef RTE_NEXT_ABI
 			PMD_INIT_LOG(ERR, "Could not enable Tx Queue %d", i);
+#else
+		{
+			PMD_INIT_LOG(ERR, "Could not enable Tx Queue %d", i);
+			if (dev->data->dev_conf.txmode.lock_mode)
+				return -1;
+		}
+#endif
 	}
 	for (i = 0; i < dev->data->nb_rx_queues; i++) {
 
@@ -5235,11 +5243,21 @@ ixgbevf_dev_rxtx_start(struct rte_eth_dev *dev)
 			rxdctl = IXGBE_READ_REG(hw, IXGBE_VFRXDCTL(i));
 		} while (--poll_ms && !(rxdctl & IXGBE_RXDCTL_ENABLE));
 		if (!poll_ms)
+#ifndef RTE_NEXT_ABI
+			PMD_INIT_LOG(ERR, "Could not enable Rx Queue %d", i);
+#else
+		{
 			PMD_INIT_LOG(ERR, "Could not enable Rx Queue %d", i);
+			if (dev->data->dev_conf.rxmode.lock_mode)
+				return -1;
+		}
+#endif
 		rte_wmb();
 		IXGBE_WRITE_REG(hw, IXGBE_VFRDT(i), rxq->nb_rx_desc - 1);
 
 	}
+
+	return 0;
 }
 
 /* Stubs needed for linkage when CONFIG_RTE_IXGBE_INC_VECTOR is set to 'n' */
@@ -5290,3 +5308,25 @@ ixgbe_rxq_vec_setup(struct ixgbe_rx_queue __rte_unused *rxq)
 {
 	return -1;
 }
+
+/**
+ * A fake function to stop receiption.
+ */
+uint16_t
+ixgbevf_recv_pkts_fake(void __rte_unused *rx_queue,
+		       struct rte_mbuf __rte_unused **rx_pkts,
+		       uint16_t __rte_unused nb_pkts)
+{
+	return 0;
+}
+
+/**
+ * A fake function to stop transmission.
+ */
+uint16_t
+ixgbevf_xmit_pkts_fake(void __rte_unused *tx_queue,
+		       struct rte_mbuf __rte_unused **tx_pkts,
+		       uint16_t __rte_unused nb_pkts)
+{
+	return 0;
+}
-- 
1.9.3