Re: [dpdk-dev] [PATCH v2] net/mlx5: fix representors detection

[Shahaf Shuler <shahafs@mellanox.com>]

Tuesday, July 24, 2018 11:37 AM, Nelio Laranjeiro:
> Subject: [PATCH v2] net/mlx5: fix representors detection
> 
> On systems where the required Netlink commands are not supported but
> Mellanox OFED is installed, representors information must be retrieved
> through sysfs.
> 
> Fixes: 4c10141488fe ("net/mlx5: add port representor awareness")
> 
> Signed-off-by: Nelio Laranjeiro <nelio.laranjeiro@6wind.com>
> 

Applied to next-net-mlx, thanks. 

> ---
> 
> Changes in v2:
> 
> On some distribution, the PF may not be able to open the sysfs file, such
> issue should not be handled as an error.
> ---
>  drivers/net/mlx5/mlx5.c        |  7 +++--
>  drivers/net/mlx5/mlx5.h        |  2 ++
>  drivers/net/mlx5/mlx5_ethdev.c | 53
> ++++++++++++++++++++++++++++++++++
>  3 files changed, 60 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/mlx5/mlx5.c b/drivers/net/mlx5/mlx5.c index
> 78a69228e..a1c0ad70a 100644
> --- a/drivers/net/mlx5/mlx5.c
> +++ b/drivers/net/mlx5/mlx5.c
> @@ -1330,7 +1330,8 @@ mlx5_pci_probe(struct rte_pci_driver *pci_drv
> __rte_unused,
>  	 * Netlink calls assuming kernel drivers are recent enough to
>  	 * support them.
>  	 *
> -	 * In the event of identification failure through Netlink, either:
> +	 * In the event of identification failure through Netlink, try again
> +	 * through sysfs, then either:
>  	 *
>  	 * 1. No device matches (n == 0), complain and bail out.
>  	 * 2. A single IB device matches (n == 1) and is not a representor, @@
> -1349,7 +1350,9 @@ mlx5_pci_probe(struct rte_pci_driver *pci_drv
> __rte_unused,
>  		if (nl_route < 0 ||
>  		    !list[i].ifindex ||
>  		    mlx5_nl_switch_info(nl_route, list[i].ifindex,
> -					&list[i].info)) {
> +					&list[i].info) ||
> +		    ((!list[i].info.representor && !list[i].info.master) &&
> +		     mlx5_sysfs_switch_info(list[i].ifindex, &list[i].info))) {
>  			list[i].ifindex = 0;
>  			memset(&list[i].info, 0, sizeof(list[i].info));
>  			continue;
> diff --git a/drivers/net/mlx5/mlx5.h b/drivers/net/mlx5/mlx5.h index
> db8a5fa01..a7f50b31f 100644
> --- a/drivers/net/mlx5/mlx5.h
> +++ b/drivers/net/mlx5/mlx5.h
> @@ -273,6 +273,8 @@ eth_rx_burst_t mlx5_select_rx_function(struct
> rte_eth_dev *dev);  unsigned int mlx5_dev_to_port_id(const struct
> rte_device *dev,
>  				 uint16_t *port_list,
>  				 unsigned int port_list_n);
> +int mlx5_sysfs_switch_info(unsigned int ifindex,
> +			   struct mlx5_switch_info *info);
> 
>  /* mlx5_mac.c */
> 
> diff --git a/drivers/net/mlx5/mlx5_ethdev.c
> b/drivers/net/mlx5/mlx5_ethdev.c index 9cf2dc5f1..4a24f8021 100644
> --- a/drivers/net/mlx5/mlx5_ethdev.c
> +++ b/drivers/net/mlx5/mlx5_ethdev.c
> @@ -1321,3 +1321,56 @@ mlx5_dev_to_port_id(const struct rte_device
> *dev, uint16_t *port_list,
>  	}
>  	return n;
>  }
> +
> +/**
> + * Get switch information associated with network interface.
> + *
> + * @param ifindex
> + *   Network interface index.
> + * @param[out] info
> + *   Switch information object, populated in case of success.
> + *
> + * @return
> + *   0 on success, a negative errno value otherwise and rte_errno is set.
> + */
> +int
> +mlx5_sysfs_switch_info(unsigned int ifindex, struct mlx5_switch_info
> +*info) {
> +	char ifname[IF_NAMESIZE];
> +	FILE *file;
> +	struct mlx5_switch_info data = { .master = 0, };
> +	bool port_name_set = false;
> +	bool port_switch_id_set = false;
> +	char c;
> +
> +	if (!if_indextoname(ifindex, ifname)) {
> +		rte_errno = errno;
> +		return -rte_errno;
> +	}
> +
> +	MKSTR(phys_port_name, "/sys/class/net/%s/phys_port_name",
> +	      ifname);
> +	MKSTR(phys_switch_id, "/sys/class/net/%s/phys_switch_id",
> +	      ifname);
> +
> +	file = fopen(phys_port_name, "rb");
> +	if (file != NULL) {
> +		port_name_set =
> +			fscanf(file, "%d%c", &data.port_name, &c) == 2 &&
> +			c == '\n';
> +		fclose(file);
> +	}
> +	file = fopen(phys_switch_id, "rb");
> +	if (file == NULL) {
> +		rte_errno = errno;
> +		return -rte_errno;
> +	}
> +	port_switch_id_set =
> +		fscanf(file, "%" SCNx64 "%c", &data.switch_id, &c) == 2 &&
> +		c == '\n';
> +	fclose(file);
> +	data.master = port_switch_id_set && !port_name_set;
> +	data.representor = port_switch_id_set && port_name_set;
> +	*info = data;
> +	return 0;
> +}
> --
> 2.18.0