Re: [dpdk-dev] [PATCH v2 2/3] net/i40e: enable hotplug detect in i40e

[Matan Azrad <matan@mellanox.com>]

Hi Guo

From: Jeff Guo
> This patch aim to enable hotplug detect in i40e pmd driver. Firstly it set the
> flags RTE_PCI_DRV_INTR_RMV in drv_flags to announce the hotplug ability,
> and then use rte_dev_event_callback_register to register the hotplug event
> callback to eal. When eal detect the hotplug event, it will call the callback to
> process it, if the event is hotplug remove, it will trigger the
> RTE_ETH_EVENT_INTR_RMV event into ethdev callback to let app process
> the hotplug for the ethdev.
> 
> This is an example for other driver, that if any driver support hotplug feature
> could be use this way to enable hotplug detect.
> 
> Signed-off-by: Jeff Guo <jia.guo@intel.com>
> ---
> v2->v1:
> no v1, add hotplug detect in ixgbe for new.
> ---
>  drivers/net/i40e/i40e_ethdev.c | 46
> +++++++++++++++++++++++++++++++++++++++++-
>  1 file changed, 45 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/i40e/i40e_ethdev.c b/drivers/net/i40e/i40e_ethdev.c
> index 13c5d32..ad4231f 100644
> --- a/drivers/net/i40e/i40e_ethdev.c
> +++ b/drivers/net/i40e/i40e_ethdev.c
> @@ -688,7 +688,7 @@ static int eth_i40e_pci_remove(struct rte_pci_device
> *pci_dev)  static struct rte_pci_driver rte_i40e_pmd = {
>  	.id_table = pci_id_i40e_map,
>  	.drv_flags = RTE_PCI_DRV_NEED_MAPPING |
> RTE_PCI_DRV_INTR_LSC |
> -		     RTE_PCI_DRV_IOVA_AS_VA,
> +		     RTE_PCI_DRV_IOVA_AS_VA | RTE_PCI_DRV_INTR_RMV,
>  	.probe = eth_i40e_pci_probe,
>  	.remove = eth_i40e_pci_remove,
>  };
> @@ -1183,6 +1183,47 @@ i40e_aq_debug_write_global_register(struct
> i40e_hw *hw,
>  	return i40e_aq_debug_write_register(hw, reg_addr, reg_val,
> cmd_details);  }
> 
> +static void
> +eth_dev_event_callback(char *device_name, enum rte_dev_event_type
> type,
> +		       __rte_unused void *arg)
> +{
> +	uint32_t pid;
> +
> +	if (type >= RTE_DEV_EVENT_MAX) {
> +		fprintf(stderr, "%s called upon invalid event %d\n",
> +			__func__, type);
> +		fflush(stderr);
> +	}
> +
> +	switch (type) {
> +	case RTE_DEV_EVENT_REMOVE:
> +		PMD_DRV_LOG(INFO, "The device: %s has been
> removed!\n",
> +			    device_name);
> +
> +		if (!device_name)
> +			return;
> +
> +		for (pid = 0; pid < RTE_MAX_ETHPORTS; pid++) {
> +			if (rte_eth_devices[pid].device) {
> +				if (!strcmp(device_name,
> +				    rte_eth_devices[pid].device->name)) {

You just need to compare this PMD ethdev ports device names to the current EAL removed device name.
You should not raise RMV events for other PMD  ports.

> +					_rte_eth_dev_callback_process(
> +						&rte_eth_devices[pid],
> +						RTE_ETH_EVENT_INTR_RMV,
> NULL);
> +					continue;
> +				}
> +			}
> +		}
> +		break;
> +	case RTE_DEV_EVENT_ADD:
> +		RTE_LOG(INFO, EAL, "The device: %s has been added!\n",
> +			device_name);
> +		break;
> +	default:
> +		break;
> +	}
> +}
> +
>  static int
>  eth_i40e_dev_init(struct rte_eth_dev *dev, void *init_params
> __rte_unused)  { @@ -1442,6 +1483,9 @@ eth_i40e_dev_init(struct
> rte_eth_dev *dev, void *init_params __rte_unused)
>  	rte_intr_callback_register(intr_handle,
>  				   i40e_dev_interrupt_handler, dev);
> 
> +	/* register the device event callback */
> +	rte_dev_event_callback_register(NULL, eth_dev_event_callback,
> NULL);
> +
>  	/* configure and enable device interrupt */
>  	i40e_pf_config_irq0(hw, TRUE);
>  	i40e_pf_enable_irq0(hw);
> --
> 2.7.4