Re: [dpdk-dev] [PATCH v3 2/4] ethdev: add siblings iterators

[Slava Ovsiienko <viacheslavo@mellanox.com>]

> -----Original Message-----
> From: dev <dev-bounces@dpdk.org> On Behalf Of Thomas Monjalon
> Sent: Monday, April 1, 2019 5:27
> To: gaetan.rivet@6wind.com; Ferruh Yigit <ferruh.yigit@intel.com>; Andrew
> Rybchenko <arybchenko@solarflare.com>
> Cc: dev@dpdk.org
> Subject: [dpdk-dev] [PATCH v3 2/4] ethdev: add siblings iterators
> 
> If multiple ports share the same hardware device (rte_device), they are
> siblings and can be found thanks to the new functions and loop macros.
> One iterator takes a port id as reference, while the other one directly refers
> to the parent device.
> 
> The ownership is not checked because siblings may have different owners.
> 
> Signed-off-by: Thomas Monjalon <thomas@monjalon.net>
Tested-by: Viacheslav Ovsiienko <mellanox.com>

> ---
> v2: Reviewed-by: Andrew Rybchenko - not kept because of changes in v3
> 
> v3:
> 	- fix logic + re-use rte_eth_find_next()
> 	- longer parameter names
> 	- more and better doxygen comments
> ---
>  lib/librte_ethdev/rte_ethdev.c           | 19 +++++++
>  lib/librte_ethdev/rte_ethdev.h           | 63 ++++++++++++++++++++++++
>  lib/librte_ethdev/rte_ethdev_version.map |  2 +
>  3 files changed, 84 insertions(+)
> 
> diff --git a/lib/librte_ethdev/rte_ethdev.c b/lib/librte_ethdev/rte_ethdev.c
> index 33cffc498..3b125a642 100644
> --- a/lib/librte_ethdev/rte_ethdev.c
> +++ b/lib/librte_ethdev/rte_ethdev.c
> @@ -339,6 +339,25 @@ rte_eth_find_next(uint16_t port_id)
>  	return port_id;
>  }
> 
> +uint16_t __rte_experimental
> +rte_eth_find_next_of(uint16_t port_id, const struct rte_device *parent)
> +{
> +	port_id = rte_eth_find_next(port_id);
> +	while (port_id < RTE_MAX_ETHPORTS &&
> +			rte_eth_devices[port_id].device != parent)
> +		port_id = rte_eth_find_next(port_id + 1);
> +
> +	return port_id;
> +}
> +
> +uint16_t __rte_experimental
> +rte_eth_find_next_sibling(uint16_t port_id, uint16_t ref_port_id) {
> +	RTE_ETH_VALID_PORTID_OR_ERR_RET(ref_port_id,
> RTE_MAX_ETHPORTS);
> +	return rte_eth_find_next_of(port_id,
> +			rte_eth_devices[ref_port_id].device);
> +}
> +
>  static void
>  rte_eth_dev_shared_data_prepare(void)
>  {
> diff --git a/lib/librte_ethdev/rte_ethdev.h b/lib/librte_ethdev/rte_ethdev.h
> index b6023c050..3d5bacaee 100644
> --- a/lib/librte_ethdev/rte_ethdev.h
> +++ b/lib/librte_ethdev/rte_ethdev.h
> @@ -1387,6 +1387,69 @@ uint16_t rte_eth_find_next(uint16_t port_id);
> #define RTE_ETH_FOREACH_DEV(p) \
>  	RTE_ETH_FOREACH_DEV_OWNED_BY(p,
> RTE_ETH_DEV_NO_OWNER)
> 
> +/**
> + * @warning
> + * @b EXPERIMENTAL: this API may change without prior notice.
> + *
> + * Iterates over ethdev ports of a specified device.
> + *
> + * @param port_id_start
> + *   The id of the next possible valid port.
> + * @param parent
> + *   The generic device behind the ports to iterate.
> + * @return
> + *   Next port id of the device, possibly port_id_start,
> + *   RTE_MAX_ETHPORTS if there is none.
> + */
> +__rte_experimental
> +uint16_t rte_eth_find_next_of(uint16_t port_id_start,
> +		const struct rte_device *parent);
> +
> +/**
> + * Macro to iterate over all ethdev ports of a specified device.
> + *
> + * @param port_id
> + *   The id of the matching port being iterated.
> + * @param parent
> + *   The rte_device pointer matching the iterated ports.
> + */
> +#define RTE_ETH_FOREACH_DEV_OF(port_id, parent) \
> +	for (port_id = rte_eth_find_next_of(0, parent); \
> +		port_id < RTE_MAX_ETHPORTS; \
> +		port_id = rte_eth_find_next_of(port_id + 1, parent))
> +
> +/**
> + * @warning
> + * @b EXPERIMENTAL: this API may change without prior notice.
> + *
> + * Iterates over sibling ethdev ports (i.e. sharing the same rte_device).
> + *
> + * @param port_id_start
> + *   The id of the next possible valid sibling port.
> + * @param ref_port_id
> + *   The id of a reference port to compare rte_device with.
> + * @return
> + *   Next sibling port id, possibly port_id_start or ref_port_id itself,
> + *   RTE_MAX_ETHPORTS if there is none.
> + */
> +__rte_experimental
> +uint16_t rte_eth_find_next_sibling(uint16_t port_id_start,
> +		uint16_t ref_port_id);
> +
> +/**
> + * Macro to iterate over all ethdev ports sharing the same rte_device
> + * as the specified port.
> + * Note: the specified reference port is part of the loop iterations.
> + *
> + * @param port_id
> + *   The id of the matching port being iterated.
> + * @param ref_port_id
> + *   The id of the port being compared.
> + */
> +#define RTE_ETH_FOREACH_DEV_SIBLING(port_id, ref_port_id) \
> +	for (port_id = rte_eth_find_next_sibling(0, ref_port_id); \
> +		port_id < RTE_MAX_ETHPORTS; \
> +		port_id = rte_eth_find_next_sibling(port_id + 1, ref_port_id))
> 
>  /**
>   * @warning
> diff --git a/lib/librte_ethdev/rte_ethdev_version.map
> b/lib/librte_ethdev/rte_ethdev_version.map
> index 92ac3de25..b37a4167d 100644
> --- a/lib/librte_ethdev/rte_ethdev_version.map
> +++ b/lib/librte_ethdev/rte_ethdev_version.map
> @@ -245,6 +245,8 @@ EXPERIMENTAL {
>  	rte_eth_dev_owner_set;
>  	rte_eth_dev_owner_unset;
>  	rte_eth_dev_rx_intr_ctl_q_get_fd;
> +	rte_eth_find_next_of;
> +	rte_eth_find_next_sibling;
>  	rte_eth_switch_domain_alloc;
>  	rte_eth_switch_domain_free;
>  	rte_flow_conv;
> --
> 2.21.0