iavf: Refactor iavf state machine tracking

Replace state changes of iavf state machine
with a method that also tracks the previous
state the machine was on.

This change is required for further work with
refactoring init and watchdog state machines.

Tracking of previous state would help us
recover iavf after failure has occurred.
Signed-off-by: Jakub Pawlak <jakub.pawlak@intel.com>
Signed-off-by: Jan Sokolowski <jan.sokolowski@intel.com>
Signed-off-by: Mateusz Palczewski <mateusz.palczewski@intel.com>
Tested-by: Konrad Jankowski <konrad0.jankowski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

drivers/net/ethernet/intel/iavf/iavf.h

@@ -312,6 +312,7 @@ struct iavf_adapter {
 	struct iavf_hw hw; /* defined in iavf_type.h */
 
 	enum iavf_state_t state;
+	enum iavf_state_t last_state;
 	unsigned long crit_section;
 
 	struct delayed_work watchdog_task;
@@ -393,6 +394,15 @@ struct iavf_device {
 extern char iavf_driver_name[];
 extern struct workqueue_struct *iavf_wq;
 
+static inline void iavf_change_state(struct iavf_adapter *adapter,
+				     enum iavf_state_t state)
+{
+	if (adapter->state != state) {
+		adapter->last_state = adapter->state;
+		adapter->state = state;
+	}
+}
+
 int iavf_up(struct iavf_adapter *adapter);
 void iavf_down(struct iavf_adapter *adapter);
 int iavf_process_config(struct iavf_adapter *adapter);

drivers/net/ethernet/intel/iavf/iavf_main.c

@@ -960,7 +960,7 @@ static void iavf_configure(struct iavf_adapter *adapter)
  **/
 static void iavf_up_complete(struct iavf_adapter *adapter)
 {
-	adapter->state = __IAVF_RUNNING;
+	iavf_change_state(adapter, __IAVF_RUNNING);
 	clear_bit(__IAVF_VSI_DOWN, adapter->vsi.state);
 
 	iavf_napi_enable_all(adapter);
@@ -1729,7 +1729,7 @@ static int iavf_startup(struct iavf_adapter *adapter)
 		iavf_shutdown_adminq(hw);
 		goto err;
 	}
-	adapter->state = __IAVF_INIT_VERSION_CHECK;
+	iavf_change_state(adapter, __IAVF_INIT_VERSION_CHECK);
 err:
 	return err;
 }
@@ -1753,7 +1753,7 @@ static int iavf_init_version_check(struct iavf_adapter *adapter)
 	if (!iavf_asq_done(hw)) {
 		dev_err(&pdev->dev, "Admin queue command never completed\n");
 		iavf_shutdown_adminq(hw);
-		adapter->state = __IAVF_STARTUP;
+		iavf_change_state(adapter, __IAVF_STARTUP);
 		goto err;
 	}
 
@@ -1776,8 +1776,7 @@ static int iavf_init_version_check(struct iavf_adapter *adapter)
 			err);
 		goto err;
 	}
-	adapter->state = __IAVF_INIT_GET_RESOURCES;
-
+	iavf_change_state(adapter, __IAVF_INIT_GET_RESOURCES);
 err:
 	return err;
 }
@@ -1893,7 +1892,7 @@ static int iavf_init_get_resources(struct iavf_adapter *adapter)
 	if (netdev->features & NETIF_F_GRO)
 		dev_info(&pdev->dev, "GRO is enabled\n");
 
-	adapter->state = __IAVF_DOWN;
+	iavf_change_state(adapter, __IAVF_DOWN);
 	set_bit(__IAVF_VSI_DOWN, adapter->vsi.state);
 	rtnl_unlock();
 
@@ -1941,7 +1940,7 @@ static void iavf_watchdog_task(struct work_struct *work)
 		goto restart_watchdog;
 
 	if (adapter->flags & IAVF_FLAG_PF_COMMS_FAILED)
-		adapter->state = __IAVF_COMM_FAILED;
+		iavf_change_state(adapter, __IAVF_COMM_FAILED);
 
 	switch (adapter->state) {
 	case __IAVF_COMM_FAILED:
@@ -1952,7 +1951,7 @@ static void iavf_watchdog_task(struct work_struct *work)
 			/* A chance for redemption! */
 			dev_err(&adapter->pdev->dev,
 				"Hardware came out of reset. Attempting reinit.\n");
-			adapter->state = __IAVF_STARTUP;
+			iavf_change_state(adapter, __IAVF_STARTUP);
 			adapter->flags &= ~IAVF_FLAG_PF_COMMS_FAILED;
 			queue_delayed_work(iavf_wq, &adapter->init_task, 10);
 			mutex_unlock(&adapter->crit_lock);
@@ -2002,6 +2001,7 @@ static void iavf_watchdog_task(struct work_struct *work)
 	/* check for hw reset */
 	reg_val = rd32(hw, IAVF_VF_ARQLEN1) & IAVF_VF_ARQLEN1_ARQENABLE_MASK;
 	if (!reg_val) {
+		iavf_change_state(adapter, __IAVF_RESETTING);
 		adapter->flags |= IAVF_FLAG_RESET_PENDING;
 		adapter->aq_required = 0;
 		adapter->current_op = VIRTCHNL_OP_UNKNOWN;
@@ -2081,7 +2081,7 @@ static void iavf_disable_vf(struct iavf_adapter *adapter)
 	adapter->netdev->flags &= ~IFF_UP;
 	mutex_unlock(&adapter->crit_lock);
 	adapter->flags &= ~IAVF_FLAG_RESET_PENDING;
-	adapter->state = __IAVF_DOWN;
+	iavf_change_state(adapter, __IAVF_DOWN);
 	wake_up(&adapter->down_waitqueue);
 	dev_info(&adapter->pdev->dev, "Reset task did not complete, VF disabled\n");
 }
@@ -2191,7 +2191,7 @@ static void iavf_reset_task(struct work_struct *work)
 	}
 	iavf_irq_disable(adapter);
 
-	adapter->state = __IAVF_RESETTING;
+	iavf_change_state(adapter, __IAVF_RESETTING);
 	adapter->flags &= ~IAVF_FLAG_RESET_PENDING;
 
 	/* free the Tx/Rx rings and descriptors, might be better to just
@@ -2291,11 +2291,14 @@ static void iavf_reset_task(struct work_struct *work)
 
 		iavf_configure(adapter);
 
+		/* iavf_up_complete() will switch device back
+		 * to __IAVF_RUNNING
+		 */
 		iavf_up_complete(adapter);
 
 		iavf_irq_enable(adapter, true);
 	} else {
-		adapter->state = __IAVF_DOWN;
+		iavf_change_state(adapter, __IAVF_DOWN);
 		wake_up(&adapter->down_waitqueue);
 	}
 	mutex_unlock(&adapter->client_lock);
@@ -3297,7 +3300,7 @@ static int iavf_close(struct net_device *netdev)
 		adapter->flags |= IAVF_FLAG_CLIENT_NEEDS_CLOSE;
 
 	iavf_down(adapter);
-	adapter->state = __IAVF_DOWN_PENDING;
+	iavf_change_state(adapter, __IAVF_DOWN_PENDING);
 	iavf_free_traffic_irqs(adapter);
 
 	mutex_unlock(&adapter->crit_lock);
@@ -3679,7 +3682,7 @@ static void iavf_init_task(struct work_struct *work)
 			"Failed to communicate with PF; waiting before retry\n");
 		adapter->flags |= IAVF_FLAG_PF_COMMS_FAILED;
 		iavf_shutdown_adminq(hw);
-		adapter->state = __IAVF_STARTUP;
+		iavf_change_state(adapter, __IAVF_STARTUP);
 		queue_delayed_work(iavf_wq, &adapter->init_task, HZ * 5);
 		goto out;
 	}
@@ -3705,7 +3708,7 @@ static void iavf_shutdown(struct pci_dev *pdev)
 	if (iavf_lock_timeout(&adapter->crit_lock, 5000))
 		dev_warn(&adapter->pdev->dev, "failed to acquire crit_lock in %s\n", __FUNCTION__);
 	/* Prevent the watchdog from running. */
-	adapter->state = __IAVF_REMOVE;
+	iavf_change_state(adapter, __IAVF_REMOVE);
 	adapter->aq_required = 0;
 	mutex_unlock(&adapter->crit_lock);
 
@@ -3778,7 +3781,7 @@ static int iavf_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	hw->back = adapter;
 
 	adapter->msg_enable = BIT(DEFAULT_DEBUG_LEVEL_SHIFT) - 1;
-	adapter->state = __IAVF_STARTUP;
+	iavf_change_state(adapter, __IAVF_STARTUP);
 
 	/* Call save state here because it relies on the adapter struct. */
 	pci_save_state(pdev);
@@ -3954,7 +3957,7 @@ static void iavf_remove(struct pci_dev *pdev)
 		dev_warn(&adapter->pdev->dev, "failed to acquire crit_lock in %s\n", __FUNCTION__);
 
 	/* Shut down all the garbage mashers on the detention level */
-	adapter->state = __IAVF_REMOVE;
+	iavf_change_state(adapter, __IAVF_REMOVE);
 	adapter->aq_required = 0;
 	adapter->flags &= ~IAVF_FLAG_REINIT_ITR_NEEDED;
 	iavf_free_all_tx_resources(adapter);

drivers/net/ethernet/intel/iavf/iavf_virtchnl.c

@@ -1735,7 +1735,7 @@ void iavf_virtchnl_completion(struct iavf_adapter *adapter,
 		iavf_free_all_tx_resources(adapter);
 		iavf_free_all_rx_resources(adapter);
 		if (adapter->state == __IAVF_DOWN_PENDING) {
-			adapter->state = __IAVF_DOWN;
+			iavf_change_state(adapter, __IAVF_DOWN);
 			wake_up(&adapter->down_waitqueue);
 		}
 		break;