[PATCH 1/3] ixgbe: make link update thread periodic

[Jeff Daly <jeffd@silicom-usa.com>]

Rather than run-to-completion, allow the link update thread to be
periodic.  This will set the stage for properly handling hot-plugging.

Signed-off-by: Jeff Daly <jeffd@silicom-usa.com>
Inspired-by: Stephen Douthit <stephend@silicom-usa.com>
---
 drivers/net/ixgbe/base/ixgbe_common.c |   4 +-
 drivers/net/ixgbe/ixgbe_ethdev.c      | 180 ++++++++++----------------
 2 files changed, 71 insertions(+), 113 deletions(-)

diff --git a/drivers/net/ixgbe/base/ixgbe_common.c b/drivers/net/ixgbe/base/ixgbe_common.c
index aa843bd5c4a5..712062306491 100644
--- a/drivers/net/ixgbe/base/ixgbe_common.c
+++ b/drivers/net/ixgbe/base/ixgbe_common.c
@@ -4154,8 +4154,8 @@ s32 ixgbe_check_mac_link_generic(struct ixgbe_hw *hw, ixgbe_link_speed *speed,
 			break;
 		case ixgbe_mac_X550EM_x:
 		case ixgbe_mac_X550EM_a:
-			sfp_cage_full = IXGBE_READ_REG(hw, IXGBE_ESDP) &
-					IXGBE_ESDP_SDP0;
+			sfp_cage_full = !(IXGBE_READ_REG(hw, IXGBE_ESDP) &
+					  IXGBE_ESDP_SDP0);
 			break;
 		default:
 			/* sanity check - No SFP+ devices here */
diff --git a/drivers/net/ixgbe/ixgbe_ethdev.c b/drivers/net/ixgbe/ixgbe_ethdev.c
index 2da3f67bbc78..81b15ad28212 100644
--- a/drivers/net/ixgbe/ixgbe_ethdev.c
+++ b/drivers/net/ixgbe/ixgbe_ethdev.c
@@ -230,8 +230,6 @@ static int ixgbe_dev_interrupt_action(struct rte_eth_dev *dev);
 static void ixgbe_dev_interrupt_handler(void *param);
 static void ixgbe_dev_interrupt_delayed_handler(void *param);
 static void *ixgbe_dev_setup_link_thread_handler(void *param);
-static int ixgbe_dev_wait_setup_link_complete(struct rte_eth_dev *dev,
-					      uint32_t timeout_ms);
 
 static int ixgbe_add_rar(struct rte_eth_dev *dev,
 			struct rte_ether_addr *mac_addr,
@@ -1039,7 +1037,6 @@ ixgbe_swfw_lock_reset(struct ixgbe_hw *hw)
 static int
 eth_ixgbe_dev_init(struct rte_eth_dev *eth_dev, void *init_params __rte_unused)
 {
-	struct ixgbe_adapter *ad = eth_dev->data->dev_private;
 	struct rte_pci_device *pci_dev = RTE_ETH_DEV_TO_PCI(eth_dev);
 	struct rte_intr_handle *intr_handle = pci_dev->intr_handle;
 	struct ixgbe_hw *hw =
@@ -1094,7 +1091,6 @@ eth_ixgbe_dev_init(struct rte_eth_dev *eth_dev, void *init_params __rte_unused)
 		return 0;
 	}
 
-	rte_atomic32_clear(&ad->link_thread_running);
 	rte_eth_copy_pci_info(eth_dev, pci_dev);
 	eth_dev->data->dev_flags |= RTE_ETH_DEV_AUTOFILL_QUEUE_XSTATS;
 
@@ -1547,7 +1543,6 @@ eth_ixgbevf_dev_init(struct rte_eth_dev *eth_dev)
 {
 	int diag;
 	uint32_t tc, tcs;
-	struct ixgbe_adapter *ad = eth_dev->data->dev_private;
 	struct rte_pci_device *pci_dev = RTE_ETH_DEV_TO_PCI(eth_dev);
 	struct rte_intr_handle *intr_handle = pci_dev->intr_handle;
 	struct ixgbe_hw *hw =
@@ -1590,7 +1585,6 @@ eth_ixgbevf_dev_init(struct rte_eth_dev *eth_dev)
 		return 0;
 	}
 
-	rte_atomic32_clear(&ad->link_thread_running);
 	ixgbevf_parse_devargs(eth_dev->data->dev_private,
 			      pci_dev->device.devargs);
 
@@ -2558,8 +2552,11 @@ ixgbe_flow_ctrl_enable(struct rte_eth_dev *dev, struct ixgbe_hw *hw)
 static int
 ixgbe_dev_start(struct rte_eth_dev *dev)
 {
+	struct ixgbe_adapter *ad = dev->data->dev_private;
 	struct ixgbe_hw *hw =
 		IXGBE_DEV_PRIVATE_TO_HW(dev->data->dev_private);
+	struct ixgbe_interrupt *intr =
+		IXGBE_DEV_PRIVATE_TO_INTR(dev->data->dev_private);
 	struct ixgbe_vf_info *vfinfo =
 		*IXGBE_DEV_PRIVATE_TO_P_VFDATA(dev->data->dev_private);
 	struct rte_pci_device *pci_dev = RTE_ETH_DEV_TO_PCI(dev);
@@ -2580,9 +2577,6 @@ ixgbe_dev_start(struct rte_eth_dev *dev)
 
 	PMD_INIT_FUNC_TRACE();
 
-	/* Stop the link setup handler before resetting the HW. */
-	ixgbe_dev_wait_setup_link_complete(dev, 0);
-
 	/* disable uio/vfio intr/eventfd mapping */
 	rte_intr_disable(intr_handle);
 
@@ -2700,8 +2694,16 @@ ixgbe_dev_start(struct rte_eth_dev *dev)
 
 	if (ixgbe_is_sfp(hw) && hw->phy.multispeed_fiber) {
 		err = hw->mac.ops.setup_sfp(hw);
-		if (err)
+		intr->flags |= IXGBE_FLAG_NEED_LINK_CONFIG;
+		err = rte_ctrl_thread_create(&ad->link_thread_tid,
+					     "ixgbe-service-tid",
+					     NULL,
+					     ixgbe_dev_setup_link_thread_handler,
+					     dev);
+		if (err) {
+			PMD_DRV_LOG(ERR, "service_thread err");
 			goto error;
+		}
 	}
 
 	if (hw->mac.ops.get_media_type(hw) == ixgbe_media_type_copper) {
@@ -2825,12 +2827,6 @@ ixgbe_dev_start(struct rte_eth_dev *dev)
 	if (err)
 		goto error;
 
-	/*
-	 * Update link status right before return, because it may
-	 * start link configuration process in a separate thread.
-	 */
-	ixgbe_dev_link_update(dev, 0);
-
 	/* setup the macsec setting register */
 	if (macsec_setting->offload_en)
 		ixgbe_dev_macsec_register_enable(dev, macsec_setting);
@@ -2860,13 +2856,21 @@ ixgbe_dev_stop(struct rte_eth_dev *dev)
 	int vf;
 	struct ixgbe_tm_conf *tm_conf =
 		IXGBE_DEV_PRIVATE_TO_TM_CONF(dev->data->dev_private);
+	void *res;
+	s32 err;
 
 	if (hw->adapter_stopped)
 		return 0;
 
 	PMD_INIT_FUNC_TRACE();
 
-	ixgbe_dev_wait_setup_link_complete(dev, 0);
+	/* Cancel the service thread */
+	err = pthread_cancel(adapter->link_thread_tid);
+	if (err)
+		PMD_DRV_LOG(ERR, "failed to cancel service thread %d", err);
+	err = pthread_join(adapter->link_thread_tid, &res);
+	if (err)
+		PMD_DRV_LOG(ERR, "failed to join service thread %d", err);
 
 	/* disable interrupts */
 	ixgbe_disable_intr(hw);
@@ -2945,7 +2949,6 @@ ixgbe_dev_set_link_up(struct rte_eth_dev *dev)
 	} else {
 		/* Turn on the laser */
 		ixgbe_enable_tx_laser(hw);
-		ixgbe_dev_link_update(dev, 0);
 	}
 
 	return 0;
@@ -2976,7 +2979,6 @@ ixgbe_dev_set_link_down(struct rte_eth_dev *dev)
 	} else {
 		/* Turn off the laser */
 		ixgbe_disable_tx_laser(hw);
-		ixgbe_dev_link_update(dev, 0);
 	}
 
 	return 0;
@@ -4129,54 +4131,58 @@ ixgbevf_check_link(struct ixgbe_hw *hw, ixgbe_link_speed *speed,
 	return ret_val;
 }
 
-/*
- * If @timeout_ms was 0, it means that it will not return until link complete.
- * It returns 1 on complete, return 0 on timeout.
- */
-static int
-ixgbe_dev_wait_setup_link_complete(struct rte_eth_dev *dev, uint32_t timeout_ms)
-{
-#define WARNING_TIMEOUT    9000 /* 9s  in total */
-	struct ixgbe_adapter *ad = dev->data->dev_private;
-	uint32_t timeout = timeout_ms ? timeout_ms : WARNING_TIMEOUT;
-
-	while (rte_atomic32_read(&ad->link_thread_running)) {
-		msec_delay(1);
-		timeout--;
-
-		if (timeout_ms) {
-			if (!timeout)
-				return 0;
-		} else if (!timeout) {
-			/* It will not return until link complete */
-			timeout = WARNING_TIMEOUT;
-			PMD_DRV_LOG(ERR, "IXGBE link thread not complete too long time!");
-		}
-	}
-
-	return 1;
-}
-
 static void *
 ixgbe_dev_setup_link_thread_handler(void *param)
 {
 	struct rte_eth_dev *dev = (struct rte_eth_dev *)param;
-	struct ixgbe_adapter *ad = dev->data->dev_private;
 	struct ixgbe_hw *hw = IXGBE_DEV_PRIVATE_TO_HW(dev->data->dev_private);
 	struct ixgbe_interrupt *intr =
 		IXGBE_DEV_PRIVATE_TO_INTR(dev->data->dev_private);
-	u32 speed;
-	bool autoneg = false;
+	u32 speed, start, ticks, service_ms;
+	s32 err;
+	bool link_up, autoneg = false;
 
 	pthread_detach(pthread_self());
-	speed = hw->phy.autoneg_advertised;
-	if (!speed)
-		ixgbe_get_link_capabilities(hw, &speed, &autoneg);
 
-	ixgbe_setup_link(hw, speed, true);
+	while (1) {
+		service_ms = 100;
+		if (intr->flags & IXGBE_FLAG_NEED_LINK_CONFIG) {
+			speed = hw->phy.autoneg_advertised;
+
+			if (!speed)
+				ixgbe_get_link_capabilities(hw, &speed, &autoneg);
+
+			err = ixgbe_setup_link(hw, speed, true);
+
+			if (err == IXGBE_SUCCESS)
+				err = ixgbe_check_link(hw, &speed, &link_up, 0);
+
+			/* Run the service thread handler more frequently when link is
+			 * down to reduce link up latency (every 200ms vs 1s)
+			 *
+			 * Use a number of smaller sleeps to decrease exit latency when
+			 * ixgbe_dev_stop() wants this thread to join
+			 */
+			if (err == IXGBE_SUCCESS && link_up) {
+				service_ms = 2000;
+				intr->flags &= ~IXGBE_FLAG_NEED_LINK_CONFIG;
+			}
+
+			if (!ixgbe_dev_link_update(dev, 0)) {
+				ixgbe_dev_link_status_print(dev);
+				rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_LSC, NULL);
+			}
+		}
+
+		/* Call msec_delay in a loop with several smaller sleeps to
+		 * provide periodic thread cancellation points
+		 */
+		start = rte_get_timer_cycles();
+		ticks = (uint64_t)service_ms * rte_get_timer_hz() / 1E3;
+		while ((rte_get_timer_cycles() - start) < ticks)
+			msec_delay(100);
+	}
 
-	intr->flags &= ~IXGBE_FLAG_NEED_LINK_CONFIG;
-	rte_atomic32_clear(&ad->link_thread_running);
 	return NULL;
 }
 
@@ -4219,11 +4225,8 @@ ixgbe_dev_link_update_share(struct rte_eth_dev *dev,
 			    int wait_to_complete, int vf)
 {
 	struct ixgbe_hw *hw = IXGBE_DEV_PRIVATE_TO_HW(dev->data->dev_private);
-	struct ixgbe_adapter *ad = dev->data->dev_private;
 	struct rte_eth_link link;
 	ixgbe_link_speed link_speed = IXGBE_LINK_SPEED_UNKNOWN;
-	struct ixgbe_interrupt *intr =
-		IXGBE_DEV_PRIVATE_TO_INTR(dev->data->dev_private);
 	bool link_up;
 	int diag;
 	int wait = 1;
@@ -4238,9 +4241,6 @@ ixgbe_dev_link_update_share(struct rte_eth_dev *dev,
 
 	hw->mac.get_link_status = true;
 
-	if (intr->flags & IXGBE_FLAG_NEED_LINK_CONFIG)
-		return rte_eth_linkstatus_set(dev, &link);
-
 	/* check if it needs to wait to complete, if lsc interrupt is enabled */
 	if (wait_to_complete == 0 || dev->data->dev_conf.intr_conf.lsc != 0)
 		wait = 0;
@@ -4255,7 +4255,7 @@ ixgbe_dev_link_update_share(struct rte_eth_dev *dev,
 	else
 		diag = ixgbe_check_link(hw, &link_speed, &link_up, wait);
 
-	if (diag != 0) {
+	if (diag != 0 || !link_up) {
 		link.link_speed = RTE_ETH_SPEED_NUM_100M;
 		link.link_duplex = RTE_ETH_LINK_FULL_DUPLEX;
 		return rte_eth_linkstatus_set(dev, &link);
@@ -4267,32 +4267,6 @@ ixgbe_dev_link_update_share(struct rte_eth_dev *dev,
 			link_up = 0;
 	}
 
-	if (link_up == 0) {
-		if (ixgbe_get_media_type(hw) == ixgbe_media_type_fiber) {
-			ixgbe_dev_wait_setup_link_complete(dev, 0);
-			if (rte_atomic32_test_and_set(&ad->link_thread_running)) {
-				/* To avoid race condition between threads, set
-				 * the IXGBE_FLAG_NEED_LINK_CONFIG flag only
-				 * when there is no link thread running.
-				 */
-				intr->flags |= IXGBE_FLAG_NEED_LINK_CONFIG;
-				if (rte_ctrl_thread_create(&ad->link_thread_tid,
-					"ixgbe-link-handler",
-					NULL,
-					ixgbe_dev_setup_link_thread_handler,
-					dev) < 0) {
-					PMD_DRV_LOG(ERR,
-						"Create link thread failed!");
-					rte_atomic32_clear(&ad->link_thread_running);
-				}
-			} else {
-				PMD_DRV_LOG(ERR,
-					"Other link thread is running now!");
-			}
-		}
-		return rte_eth_linkstatus_set(dev, &link);
-	}
-
 	link.link_status = RTE_ETH_LINK_UP;
 	link.link_duplex = RTE_ETH_LINK_FULL_DUPLEX;
 
@@ -4566,6 +4540,8 @@ ixgbe_dev_link_status_print(struct rte_eth_dev *dev)
 static int
 ixgbe_dev_interrupt_action(struct rte_eth_dev *dev)
 {
+	struct rte_pci_device *pci_dev = RTE_ETH_DEV_TO_PCI(dev);
+	struct rte_intr_handle *intr_handle = pci_dev->intr_handle;
 	struct ixgbe_interrupt *intr =
 		IXGBE_DEV_PRIVATE_TO_INTR(dev->data->dev_private);
 	int64_t timeout;
@@ -4605,16 +4581,14 @@ ixgbe_dev_interrupt_action(struct rte_eth_dev *dev)
 		if (rte_eal_alarm_set(timeout * 1000,
 				      ixgbe_dev_interrupt_delayed_handler, (void *)dev) < 0)
 			PMD_DRV_LOG(ERR, "Error setting alarm");
-		else {
-			/* remember original mask */
-			intr->mask_original = intr->mask;
+		else
 			/* only disable lsc interrupt */
 			intr->mask &= ~IXGBE_EIMS_LSC;
-		}
 	}
 
 	PMD_DRV_LOG(DEBUG, "enable intr immediately");
 	ixgbe_enable_intr(dev);
+	rte_intr_ack(intr_handle);
 
 	return 0;
 }
@@ -4637,8 +4611,6 @@ static void
 ixgbe_dev_interrupt_delayed_handler(void *param)
 {
 	struct rte_eth_dev *dev = (struct rte_eth_dev *)param;
-	struct rte_pci_device *pci_dev = RTE_ETH_DEV_TO_PCI(dev);
-	struct rte_intr_handle *intr_handle = pci_dev->intr_handle;
 	struct ixgbe_interrupt *intr =
 		IXGBE_DEV_PRIVATE_TO_INTR(dev->data->dev_private);
 	struct ixgbe_hw *hw =
@@ -4668,13 +4640,10 @@ ixgbe_dev_interrupt_delayed_handler(void *param)
 		intr->flags &= ~IXGBE_FLAG_MACSEC;
 	}
 
-	/* restore original mask */
-	intr->mask = intr->mask_original;
-	intr->mask_original = 0;
+	if (dev->data->dev_conf.intr_conf.lsc != 0)
+		intr->mask |= IXGBE_EICR_LSC;
 
-	PMD_DRV_LOG(DEBUG, "enable intr in delayed handler S[%08x]", eicr);
 	ixgbe_enable_intr(dev);
-	rte_intr_ack(intr_handle);
 }
 
 /**
@@ -5316,9 +5285,6 @@ ixgbevf_dev_start(struct rte_eth_dev *dev)
 
 	PMD_INIT_FUNC_TRACE();
 
-	/* Stop the link setup handler before resetting the HW. */
-	ixgbe_dev_wait_setup_link_complete(dev, 0);
-
 	err = hw->mac.ops.reset_hw(hw);
 
 	/**
@@ -5398,12 +5364,6 @@ ixgbevf_dev_start(struct rte_eth_dev *dev)
 	/* Re-enable interrupt for VF */
 	ixgbevf_intr_enable(dev);
 
-	/*
-	 * Update link status right before return, because it may
-	 * start link configuration process in a separate thread.
-	 */
-	ixgbevf_dev_link_update(dev, 0);
-
 	hw->adapter_stopped = false;
 
 	return 0;
@@ -5422,8 +5382,6 @@ ixgbevf_dev_stop(struct rte_eth_dev *dev)
 
 	PMD_INIT_FUNC_TRACE();
 
-	ixgbe_dev_wait_setup_link_complete(dev, 0);
-
 	ixgbevf_intr_disable(dev);
 
 	dev->data->dev_started = 0;
-- 
2.25.1