Re: [PATCH v7 7/9] ethdev: add switch domain allocator

["Ananyev, Konstantin" <konstantin.ananyev@intel.com>]

> -----Original Message-----
> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Declan Doherty
> Sent: Monday, April 16, 2018 2:06 PM
> To: dev@dpdk.org
> Cc: Adrien Mazarguil <adrien.mazarguil@6wind.com>; Yigit, Ferruh <ferruh.yigit@intel.com>; Thomas Monjalon <thomas@monjalon.net>;
> Shahaf Shuler <shahafs@mellanox.com>; Doherty, Declan <declan.doherty@intel.com>
> Subject: [dpdk-dev] [PATCH v7 7/9] ethdev: add switch domain allocator
> 
> Signed-off-by: Declan Doherty <declan.doherty@intel.com>
> ---
>  lib/librte_ether/rte_ethdev.c           | 53 +++++++++++++++++++++++++++++++++
>  lib/librte_ether/rte_ethdev_driver.h    | 39 ++++++++++++++++++++++++
>  lib/librte_ether/rte_ethdev_version.map |  3 ++
>  3 files changed, 95 insertions(+)
> 
> diff --git a/lib/librte_ether/rte_ethdev.c b/lib/librte_ether/rte_ethdev.c
> index a082b211c..d1f95161f 100644
> --- a/lib/librte_ether/rte_ethdev.c
> +++ b/lib/librte_ether/rte_ethdev.c
> @@ -4300,6 +4300,59 @@ rte_eth_devargs_parse_ports(char *str, void *data)
>  		&eth_da->nb_ports, RTE_MAX_ETHPORTS);
>  }
> 
> +/**
> + * A set of values to describe the possible states of a switch domain.
> + */
> +enum rte_eth_switch_domain_state {
> +	RTE_ETH_SWITCH_DOMAIN_UNUSED = 0,
> +	RTE_ETH_SWITCH_DOMAIN_ALLOCATED
> +};
> +
> +/**
> + * Array of switch domains available for allocation. Array is sized to
> + * RTE_MAX_ETHPORTS elements as there cannot be more active switch domains than
> + * ethdev ports in a single process.
> + */
> +struct rte_eth_dev_switch {
> +	enum rte_eth_switch_domain_state state;
> +} rte_eth_switch_domains[RTE_MAX_ETHPORTS];

Probably already discussed before, but  if we can't have more than one switch_id per port,
while we can't use port_id as switch_id?

> +
> +int __rte_experimental
> +rte_eth_switch_domain_alloc(uint16_t *domain_id)
> +{
> +	unsigned int i;
> +
> +	*domain_id = RTE_ETH_DEV_SWITCH_DOMAIN_ID_INVALID;
> +
> +	for (i = RTE_ETH_DEV_SWITCH_DOMAIN_ID_INVALID + 1;
> +		i < RTE_MAX_ETHPORTS; i++) {
> +		if (rte_eth_switch_domains[i].state ==
> +			RTE_ETH_SWITCH_DOMAIN_UNUSED) {
> +			rte_eth_switch_domains[i].state =
> +				RTE_ETH_SWITCH_DOMAIN_ALLOCATED;
> +			*domain_id = i;
> +			return 0;
> +		}
> +	}

So all we need for state is just one status bit (occupied/free)?
Wouldn't bitmap do then?

> +
> +	return -ENOSPC;
> +}
> +
> +int __rte_experimental
> +rte_eth_switch_domain_free(uint16_t domain_id)
> +{
> +	if (domain_id == RTE_ETH_DEV_SWITCH_DOMAIN_ID_INVALID ||
> +		domain_id >= RTE_MAX_ETHPORTS)
> +		return -EINVAL;
> +
> +	if (rte_eth_switch_domains[domain_id].state !=
> +		RTE_ETH_SWITCH_DOMAIN_ALLOCATED)
> +		return -EINVAL;
> +
> +	rte_eth_switch_domains[domain_id].state = RTE_ETH_SWITCH_DOMAIN_UNUSED;
> +
> +	return 0;
> +}
> 
>  static int
>  rte_eth_devargs_parse_representor_ports(char *str, void *data)
> diff --git a/lib/librte_ether/rte_ethdev_driver.h b/lib/librte_ether/rte_ethdev_driver.h
> index 3bce5747d..c22fcbde1 100644
> --- a/lib/librte_ether/rte_ethdev_driver.h
> +++ b/lib/librte_ether/rte_ethdev_driver.h
> @@ -188,6 +188,45 @@ rte_eth_linkstatus_get(const struct rte_eth_dev *dev,
>  #endif
>  }
> 
> +/**
> + * @warning
> + * @b EXPERIMENTAL: this API may change without prior notice.
> + *
> + * Allocate an unique switch domain identifier.
> + *
> + * A pool of switch domain identifiers which can be allocated on request. This
> + * will enabled devices which support the concept of switch domains to request
> + * a switch domain id which is guaranteed to be unique from other devices
> + * running in the same process.
> + *
> + * @param domain_id
> + *  switch domain identifier parameter to pass back to application
> + *
> + * @return
> + *   Negative errno value on error, 0 on success.
> + */
> +int __rte_experimental
> +rte_eth_switch_domain_alloc(uint16_t *domain_id);
> +
> +/**
> + * @warning
> + * @b EXPERIMENTAL: this API may change without prior notice.
> + *
> + * Free switch domain.
> + *
> + * Return a switch domain identifier to the pool of free identifiers after it is
> + * no longer in use by device.
> + *
> + * @param domain_id
> + *  switch domain identifier to free
> + *
> + * @return
> + *   Negative errno value on error, 0 on success.
> + */
> +int __rte_experimental
> +rte_eth_switch_domain_free(uint16_t domain_id);
> +
> +
> 
>  /** Generic Ethernet device arguments  */
>  struct rte_eth_devargs {
> diff --git a/lib/librte_ether/rte_ethdev_version.map b/lib/librte_ether/rte_ethdev_version.map
> index 62ecbdb8a..6601ef106 100644
> --- a/lib/librte_ether/rte_ethdev_version.map
> +++ b/lib/librte_ether/rte_ethdev_version.map
> @@ -236,5 +236,8 @@ EXPERIMENTAL {
>  	rt_eth_devargs_parse;
>  	rte_eth_dev_create;
>  	rte_eth_dev_destroy;
> +	rte_eth_switch_domain_alloc;
> +	rte_eth_switch_domain_free;
> +	rte_eth_switch_domains;
> 
>  } DPDK_18.05;
> --
> 2.14.3