From fe2647ab0c9970cfc2895f1671343c23fed27f44 Mon Sep 17 00:00:00 2001 From: Sudheer Mogilappagari Date: Fri, 23 Jun 2017 04:24:44 -0400 Subject: [PATCH] i40evf: prevent VF close returning before state transitions to DOWN Currently i40evf_close() can return before state transitions to __I40EVF_DOWN because of the latency involved in processing and receiving response from PF driver and scheduling of VF watchdog_task. Due to this inconsistency an immediate call to i40evf_open() fails because state is still DOWN_PENDING. When a VF interface is in up state and we try to add it as slave, The bonding driver calls dev_close() and dev_open() in short duration resulting in dev_open returning error. The ifenslave command needs to be run again for dev_open to succeed. This fix ensures that watchdog timer is scheduled immediately after admin queue operations are scheduled in i40evf_down(). In addition a wait condition is added at the end of i40evf_close so that function wont return when state is still DOWN_PENDING. The timeout value is chosen after some profiling and includes some buffer. Signed-off-by: Sudheer Mogilappagari Tested-by: Andrew Bowers Signed-off-by: Jeff Kirsher --- drivers/net/ethernet/intel/i40evf/i40evf.h | 2 ++ .../net/ethernet/intel/i40evf/i40evf_main.c | 19 +++++++++++++++++++ .../ethernet/intel/i40evf/i40evf_virtchnl.c | 4 +++- 3 files changed, 24 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/intel/i40evf/i40evf.h b/drivers/net/ethernet/intel/i40evf/i40evf.h index 7901cc85cbe5..52cf38f47349 100644 --- a/drivers/net/ethernet/intel/i40evf/i40evf.h +++ b/drivers/net/ethernet/intel/i40evf/i40evf.h @@ -43,6 +43,7 @@ #include #include #include +#include #include #include #include @@ -194,6 +195,7 @@ struct i40evf_adapter { struct work_struct adminq_task; struct delayed_work client_task; struct delayed_work init_task; + wait_queue_head_t down_waitqueue; struct i40e_q_vector *q_vectors; struct list_head vlan_filter_list; char misc_vector_name[IFNAMSIZ + 9]; diff --git a/drivers/net/ethernet/intel/i40evf/i40evf_main.c b/drivers/net/ethernet/intel/i40evf/i40evf_main.c index 22919b444ddf..21ab3ff5e9ec 100644 --- a/drivers/net/ethernet/intel/i40evf/i40evf_main.c +++ b/drivers/net/ethernet/intel/i40evf/i40evf_main.c @@ -1143,6 +1143,7 @@ void i40evf_down(struct i40evf_adapter *adapter) } clear_bit(__I40EVF_IN_CRITICAL_TASK, &adapter->crit_section); + mod_timer_pending(&adapter->watchdog_timer, jiffies + 1); } /** @@ -1794,6 +1795,7 @@ static void i40evf_disable_vf(struct i40evf_adapter *adapter) clear_bit(__I40EVF_IN_CRITICAL_TASK, &adapter->crit_section); adapter->flags &= ~I40EVF_FLAG_RESET_PENDING; adapter->state = __I40EVF_DOWN; + wake_up(&adapter->down_waitqueue); dev_info(&adapter->pdev->dev, "Reset task did not complete, VF disabled\n"); } @@ -1939,6 +1941,7 @@ continue_reset: i40evf_irq_enable(adapter, true); } else { adapter->state = __I40EVF_DOWN; + wake_up(&adapter->down_waitqueue); } return; @@ -2238,6 +2241,7 @@ err_setup_tx: static int i40evf_close(struct net_device *netdev) { struct i40evf_adapter *adapter = netdev_priv(netdev); + int status; if (adapter->state <= __I40EVF_DOWN_PENDING) return 0; @@ -2255,7 +2259,18 @@ static int i40evf_close(struct net_device *netdev) * still active and can DMA into memory. Resources are cleared in * i40evf_virtchnl_completion() after we get confirmation from the PF * driver that the rings have been stopped. + * + * Also, we wait for state to transition to __I40EVF_DOWN before + * returning. State change occurs in i40evf_virtchnl_completion() after + * VF resources are released (which occurs after PF driver processes and + * responds to admin queue commands). */ + + status = wait_event_timeout(adapter->down_waitqueue, + adapter->state == __I40EVF_DOWN, + msecs_to_jiffies(200)); + if (!status) + netdev_warn(netdev, "Device resources not yet released\n"); return 0; } @@ -2683,6 +2698,7 @@ static void i40evf_init_task(struct work_struct *work) adapter->state = __I40EVF_DOWN; set_bit(__I40E_VSI_DOWN, adapter->vsi.state); i40evf_misc_irq_enable(adapter); + wake_up(&adapter->down_waitqueue); adapter->rss_key = kzalloc(adapter->rss_key_size, GFP_KERNEL); adapter->rss_lut = kzalloc(adapter->rss_lut_size, GFP_KERNEL); @@ -2844,6 +2860,9 @@ static int i40evf_probe(struct pci_dev *pdev, const struct pci_device_id *ent) schedule_delayed_work(&adapter->init_task, msecs_to_jiffies(5 * (pdev->devfn & 0x07))); + /* Setup the wait queue for indicating transition to down status */ + init_waitqueue_head(&adapter->down_waitqueue); + return 0; err_ioremap: diff --git a/drivers/net/ethernet/intel/i40evf/i40evf_virtchnl.c b/drivers/net/ethernet/intel/i40evf/i40evf_virtchnl.c index d2bb250a71af..6c403bf1bbb8 100644 --- a/drivers/net/ethernet/intel/i40evf/i40evf_virtchnl.c +++ b/drivers/net/ethernet/intel/i40evf/i40evf_virtchnl.c @@ -991,8 +991,10 @@ void i40evf_virtchnl_completion(struct i40evf_adapter *adapter, case VIRTCHNL_OP_DISABLE_QUEUES: i40evf_free_all_tx_resources(adapter); i40evf_free_all_rx_resources(adapter); - if (adapter->state == __I40EVF_DOWN_PENDING) + if (adapter->state == __I40EVF_DOWN_PENDING) { adapter->state = __I40EVF_DOWN; + wake_up(&adapter->down_waitqueue); + } break; case VIRTCHNL_OP_VERSION: case VIRTCHNL_OP_CONFIG_IRQ_MAP: