[dpdk-dev] [PATCH v14 1/6] ethdev: add function to release port in secondary process

[Andrew Rybchenko]

On 10.08.2018 03:42, Qi Zhang wrote:
> Add driver API rte_eth_release_port_secondary to support the
> case when an ethdev need to be detached on a secondary process.
> Local state is set to unused and shared data will not be reset
> so the primary process can still use it.
>
> Signed-off-by: Qi Zhang <qi.z.zhang at intel.com>
> ---
>   lib/librte_ethdev/rte_ethdev.c           | 21 ++++++++++++++++++---
>   lib/librte_ethdev/rte_ethdev_driver.h    | 16 +++++++++++++++-
>   lib/librte_ethdev/rte_ethdev_pci.h       |  9 +++++++--
>   lib/librte_ethdev/rte_ethdev_version.map |  7 +++++++
>   4 files changed, 47 insertions(+), 6 deletions(-)
>
> diff --git a/lib/librte_ethdev/rte_ethdev.c b/lib/librte_ethdev/rte_ethdev.c
> index 4c3202505..c653bf5fa 100644
> --- a/lib/librte_ethdev/rte_ethdev.c
> +++ b/lib/librte_ethdev/rte_ethdev.c

<...>

> @@ -3532,10 +3544,13 @@ rte_eth_dev_destroy(struct rte_eth_dev *ethdev,
>   			return ret;
>   	}
>   
> -	if (rte_eal_process_type() == RTE_PROC_PRIMARY)
> -		rte_free(ethdev->data->dev_private);
> +	if (rte_eal_process_type() != RTE_PROC_PRIMARY)
> +		return rte_eth_dev_release_port_secondary(ethdev);
>   
> -	ethdev->data->dev_private = NULL;
> +	if (ethdev->data->dev_private != NULL) {

The check is not necessary, rte_free() perfectly works with NULL.

> +		rte_free(ethdev->data->dev_private);
> +		ethdev->data->dev_private = NULL;
> +	}
>   
>   	return rte_eth_dev_release_port(ethdev);
>   }
> diff --git a/lib/librte_ethdev/rte_ethdev_driver.h b/lib/librte_ethdev/rte_ethdev_driver.h
> index c6d9bc1a3..8fe82d2ab 100644
> --- a/lib/librte_ethdev/rte_ethdev_driver.h
> +++ b/lib/librte_ethdev/rte_ethdev_driver.h
> @@ -61,7 +61,7 @@ struct rte_eth_dev *rte_eth_dev_attach_secondary(const char *name);
>    * Release the specified ethdev port.
>    *
>    * @param eth_dev
> - * The *eth_dev* pointer is the address of the *rte_eth_dev* structure.
> + * Device to be detached.
>    * @return
>    *   - 0 on success, negative on error
>    */
> @@ -69,6 +69,20 @@ int rte_eth_dev_release_port(struct rte_eth_dev *eth_dev);
>   
>   /**
>    * @internal
> + * Release the specified ethdev port in the local process.
> + * Only set ethdev state to unused, but not reset shared data since
> + * it assume other processes is still using it. typically it is
> + * called by a secondary process.
> + *
> + * @param eth_dev
> + * Device to be detached.
> + * @return
> + *   - 0 on success, negative on error
> + */
> +int rte_eth_dev_release_port_secondary(struct rte_eth_dev *eth_dev);
> +
> +/**
> + * @internal
>    * Release device queues and clear its configuration to force the user
>    * application to reconfigure it. It is for internal use only.
>    *
> diff --git a/lib/librte_ethdev/rte_ethdev_pci.h b/lib/librte_ethdev/rte_ethdev_pci.h
> index f652596f4..c22022e4f 100644
> --- a/lib/librte_ethdev/rte_ethdev_pci.h
> +++ b/lib/librte_ethdev/rte_ethdev_pci.h
> @@ -135,9 +135,14 @@ rte_eth_dev_pci_allocate(struct rte_pci_device *dev, size_t private_data_size)
>   static inline void
>   rte_eth_dev_pci_release(struct rte_eth_dev *eth_dev)
>   {@@ -359,6 +359,18 @@ rte_eth_dev_attach_secondary(const char *name)
>   }
>   
>   int
> +rte_eth_dev_release_port_secondary(struct rte_eth_dev *eth_dev)
> +{
> +	if (eth_dev == NULL)
> +		return -EINVAL;
> +
> +	_rte_eth_dev_callback_process(eth_dev, RTE_ETH_EVENT_DESTROY, NULL);
> +	eth_dev->state = RTE_ETH_DEV_UNUSED;
> +
> +	return 0;
> +}
> +
> +int
>   rte_eth_dev_release_port(struct rte_eth_dev *eth_dev)
>   {
>   	if (eth_dev == NULL)
>
>
> -	if (rte_eal_process_type() == RTE_PROC_PRIMARY)
> -		rte_free(eth_dev->data->dev_private);
> +	if (rte_eal_process_type() != RTE_PROC_PRIMARY) {
> +		eth_dev->device = NULL;
> +		eth_dev->intr_handle = NULL;
> +		rte_eth_dev_release_port_secondary(eth_dev);

Is return missing here. Below comment pretends that it is primary 
process code.

> +	}
>   
> +	/* primary process */
> +	rte_free(eth_dev->data->dev_private);
>   	eth_dev->data->dev_private = NULL;
>   
>   	/*
> diff --git a/lib/librte_ethdev/rte_ethdev_version.map b/lib/librte_ethdev/rte_ethdev_version.map
> index 38f117f01..acc407f86 100644
> --- a/lib/librte_ethdev/rte_ethdev_version.map
> +++ b/lib/librte_ethdev/rte_ethdev_version.map
> @@ -220,6 +220,13 @@ DPDK_18.08 {
>   
>   } DPDK_18.05;
>   
> +DPDK_18.11 {
> +	global:
> +
> +	rte_eth_dev_release_port_secondary;
> +
> +} DPDK_18.08;
> +
>   EXPERIMENTAL {
>   	global:
>