Re: [dpdk-dev] [dpdk-stable] [PATCH 08/11] ethdev: fix port visibility before initialization

[Ferruh Yigit <ferruh.yigit@intel.com>]

On 5/9/2018 10:43 AM, Thomas Monjalon wrote:
> The port was set to the state ATTACHED during allocation.
> The consequence was to iterate over ports which are not initialized.
> 
> The state ATTACHED is now set as the last step of probing.
> 
> The uniqueness of port name is now checked before the availability
> of a port id for allocation (order reversed).
> 
> As the state is not set on allocation anymore, it is also not checked
> in the function telling whether a port is allocated or not.
> The name of the port is set on allocation, so it is enough as a check.
> 
> Fixes: 5588909af21b ("ethdev: add device iterator")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Thomas Monjalon <thomas@monjalon.net>
> Signed-off-by: Matan Azrad <matan@mellanox.com>
> ---
>  lib/librte_ethdev/rte_ethdev.c        | 18 +++++++++---------
>  lib/librte_ethdev/rte_ethdev_driver.h |  2 ++
>  2 files changed, 11 insertions(+), 9 deletions(-)
> 
> diff --git a/lib/librte_ethdev/rte_ethdev.c b/lib/librte_ethdev/rte_ethdev.c
> index 357be2dca..91cd0db11 100644
> --- a/lib/librte_ethdev/rte_ethdev.c
> +++ b/lib/librte_ethdev/rte_ethdev.c
> @@ -233,7 +233,7 @@ rte_eth_dev_allocated_lock_free(const char *name)
>  	unsigned i;
>  
>  	for (i = 0; i < RTE_MAX_ETHPORTS; i++) {
> -		if ((rte_eth_devices[i].state == RTE_ETH_DEV_ATTACHED) &&
> +		if (rte_eth_devices[i].data != NULL &&
>  		    strcmp(rte_eth_devices[i].data->name, name) == 0)
>  			return &rte_eth_devices[i];
>  	}
> @@ -278,7 +278,6 @@ eth_dev_get(uint16_t port_id)
>  	struct rte_eth_dev *eth_dev = &rte_eth_devices[port_id];
>  
>  	eth_dev->data = &rte_eth_dev_shared_data->data[port_id];
> -	eth_dev->state = RTE_ETH_DEV_ATTACHED;
>  
>  	eth_dev_last_created_port = port_id;
>  
> @@ -296,16 +295,15 @@ rte_eth_dev_allocate(const char *name)
>  	/* Synchronize port creation between primary and secondary threads. */
>  	rte_spinlock_lock(&rte_eth_dev_shared_data->ownership_lock);
>  
> -	port_id = rte_eth_dev_find_free_port();
> -	if (port_id == RTE_MAX_ETHPORTS) {
> -		ethdev_log(ERR, "Reached maximum number of Ethernet ports");
> +	if (rte_eth_dev_allocated_lock_free(name) != NULL) {
> +		ethdev_log(ERR, "Ethernet device with name %s already allocated",
> +				name);
>  		goto unlock;
>  	}
>  
> -	if (rte_eth_dev_allocated_lock_free(name) != NULL) {
> -		ethdev_log(ERR,
> -			"Ethernet Device with name %s already allocated!",
> -			name);
> +	port_id = rte_eth_dev_find_free_port();
> +	if (port_id == RTE_MAX_ETHPORTS) {
> +		ethdev_log(ERR, "Reached maximum number of Ethernet ports");
>  		goto unlock;
>  	}
>  
> @@ -3387,6 +3385,8 @@ rte_eth_dev_probing_finish(struct rte_eth_dev *dev)
>  {
>  	if (dev == NULL)
>  		return;
> +
> +	dev->state = RTE_ETH_DEV_ATTACHED;

Aren't ethdev allocation and probe in different levels? Why not make ethdev
allocation self sufficient but tie it to the device probe() ?

>  }
>  
>  int
> diff --git a/lib/librte_ethdev/rte_ethdev_driver.h b/lib/librte_ethdev/rte_ethdev_driver.h
> index 3821f0b1d..3640dff68 100644
> --- a/lib/librte_ethdev/rte_ethdev_driver.h
> +++ b/lib/librte_ethdev/rte_ethdev_driver.h
> @@ -106,6 +106,8 @@ int _rte_eth_dev_callback_process(struct rte_eth_dev *dev,
>   * This is the last step of device probing.
>   * It must be called after a port is allocated and initialized successfully.
>   *
> + * The state is set as RTE_ETH_DEV_ATTACHED.
> + *
>   * @param dev
>   *  New ethdev port.
>   */
>