Re: [PATCH v2 1/1] net/mlx5: add representor recognition on kernels 5.x

[Shahaf Shuler <shahafs@mellanox.com>]

Monday, February 25, 2019 1:01 PM, Viacheslav Ovsiienko:
> Subject: [dpdk-dev] [PATCH v2 1/1] net/mlx5: add representor recognition
> on kernels 5.x
> 
> The master device and VF representors were distinguished by presence of
> port name, master device did not have one. The new Linux kernels starting
> from 5.0 provide the port name for master device and the implemented
> representor recognizing method does not work.
> The new recognizing method is based on quiering the VF number, created on
> the base of the device.
> 
> The IFLA_NUM_VF attribute is returned by kernel if IFLA_EXT_MASK
> attribute is specified in the Netlink request message.
> 
> Also the presence of device symlink in device sysfs folder is added to
> distinguish representors with sysfs based method.

w/ kernel 5.x, there is also a new naming scheme for representor, right?
Wouldn't it be simpler to use it in order to decide uplink/regular representor? 

There is already patch for it from Dekel:
https://patches.dpdk.org/patch/50771/

> 
> Signed-off-by: Viacheslav Ovsiienko <viacheslavo@mellanox.com>
> 
> ---
> v2:
>     fopen is replaced with opendir to detect whether directory exists
> 
> v1:
> 
> https://emea01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fpatc
> hes.dpdk.org%2Fpatch%2F50411%2F&amp;data=02%7C01%7Cshahafs%40m
> ellanox.com%7C570dc79e8c0f40b23a7208d69b109fa0%7Ca652971c7d2e4d9b
> a6a4d149256f461b%7C0%7C0%7C636866893031018956&amp;sdata=jftQKX8B
> d1ZVcT38q6TLSukJYMo9VRIyEPEHhFu00S4%3D&amp;reserved=0
> ---
>  drivers/net/mlx5/Makefile      | 10 ++++++++++
>  drivers/net/mlx5/meson.build   |  4 ++++
>  drivers/net/mlx5/mlx5_ethdev.c | 13 +++++++++++--
>  drivers/net/mlx5/mlx5_nl.c     | 25 ++++++++++++++++++++++---
>  4 files changed, 47 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/net/mlx5/Makefile b/drivers/net/mlx5/Makefile index
> 9a7da18..c326494 100644
> --- a/drivers/net/mlx5/Makefile
> +++ b/drivers/net/mlx5/Makefile
> @@ -226,6 +226,16 @@ mlx5_autoconf.h.new: $(RTE_SDK)/buildtools/auto-
> config-h.sh
>  		enum RDMA_NLDEV_ATTR_NDEV_INDEX \
>  		$(AUTOCONF_OUTPUT)
>  	$Q sh -- '$<' '$@' \
> +		HAVE_IFLA_NUM_VF \
> +		linux/if_link.h \
> +		enum IFLA_NUM_VF \
> +		$(AUTOCONF_OUTPUT)
> +	$Q sh -- '$<' '$@' \
> +		HAVE_IFLA_EXT_MASK \
> +		linux/if_link.h \
> +		enum IFLA_EXT_MASK \
> +		$(AUTOCONF_OUTPUT)
> +	$Q sh -- '$<' '$@' \
>  		HAVE_IFLA_PHYS_SWITCH_ID \
>  		linux/if_link.h \
>  		enum IFLA_PHYS_SWITCH_ID \
> diff --git a/drivers/net/mlx5/meson.build b/drivers/net/mlx5/meson.build
> index 4540c45..0bb2f3a 100644
> --- a/drivers/net/mlx5/meson.build
> +++ b/drivers/net/mlx5/meson.build
> @@ -133,6 +133,10 @@ if build
>  		'ETHTOOL_LINK_MODE_50000baseCR2_Full_BIT' ],
>  		[ 'HAVE_ETHTOOL_LINK_MODE_100G', 'linux/ethtool.h',
>  		'ETHTOOL_LINK_MODE_100000baseKR4_Full_BIT' ],
> +		[ 'HAVE_IFLA_NUM_VF', 'linux/if_link.h',
> +		'IFLA_NUM_VF' ],
> +		[ 'HAVE_IFLA_EXT_MASK', 'linux/if_link.h',
> +		'IFLA_EXT_MASK' ],
>  		[ 'HAVE_IFLA_PHYS_SWITCH_ID', 'linux/if_link.h',
>  		'IFLA_PHYS_SWITCH_ID' ],
>  		[ 'HAVE_IFLA_PHYS_PORT_NAME', 'linux/if_link.h', diff --git
> a/drivers/net/mlx5/mlx5_ethdev.c b/drivers/net/mlx5/mlx5_ethdev.c index
> 8158b4a..c30fcb0 100644
> --- a/drivers/net/mlx5/mlx5_ethdev.c
> +++ b/drivers/net/mlx5/mlx5_ethdev.c
> @@ -1354,9 +1354,11 @@ int mlx5_fw_version_get(struct rte_eth_dev
> *dev, char *fw_ver, size_t fw_size)  {
>  	char ifname[IF_NAMESIZE];
>  	FILE *file;
> +	DIR *dir;
>  	struct mlx5_switch_info data = { .master = 0, };
>  	bool port_name_set = false;
>  	bool port_switch_id_set = false;
> +	bool device_dir = false;
>  	char c;
> 
>  	if (!if_indextoname(ifindex, ifname)) { @@ -1368,6 +1370,8 @@ int
> mlx5_fw_version_get(struct rte_eth_dev *dev, char *fw_ver, size_t
> fw_size)
>  	      ifname);
>  	MKSTR(phys_switch_id, "/sys/class/net/%s/phys_switch_id",
>  	      ifname);
> +	MKSTR(pci_device, "/sys/class/net/%s/device",
> +	      ifname);
> 
>  	file = fopen(phys_port_name, "rb");
>  	if (file != NULL) {
> @@ -1385,8 +1389,13 @@ int mlx5_fw_version_get(struct rte_eth_dev
> *dev, char *fw_ver, size_t fw_size)
>  		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;
> +	dir = opendir(pci_device);
> +	if (dir != NULL) {
> +		closedir(dir);
> +		device_dir = true;
> +	}
> +	data.master = port_switch_id_set && (!port_name_set ||
> device_dir);
> +	data.representor = port_switch_id_set && port_name_set &&
> !device_dir;
>  	*info = data;
>  	return 0;
>  }
> diff --git a/drivers/net/mlx5/mlx5_nl.c b/drivers/net/mlx5/mlx5_nl.c index
> d61826a..694edf1 100644
> --- a/drivers/net/mlx5/mlx5_nl.c
> +++ b/drivers/net/mlx5/mlx5_nl.c
> @@ -65,6 +65,12 @@
>  #endif
> 
>  /* These are normally found in linux/if_link.h. */
> +#ifndef HAVE_IFLA_NUM_VF
> +#define IFLA_NUM_VF 21
> +#endif
> +#ifndef HAVE_IFLA_EXT_MASK
> +#define IFLA_EXT_MASK 29
> +#endif
>  #ifndef HAVE_IFLA_PHYS_SWITCH_ID
>  #define IFLA_PHYS_SWITCH_ID 36
>  #endif
> @@ -836,6 +842,7 @@ struct mlx5_nl_ifindex_data {
>  	size_t off = NLMSG_LENGTH(sizeof(struct ifinfomsg));
>  	bool port_name_set = false;
>  	bool switch_id_set = false;
> +	bool num_vf_set = false;
> 
>  	if (nh->nlmsg_type != RTM_NEWLINK)
>  		goto error;
> @@ -848,6 +855,9 @@ struct mlx5_nl_ifindex_data {
>  		if (ra->rta_len > nh->nlmsg_len - off)
>  			goto error;
>  		switch (ra->rta_type) {
> +		case IFLA_NUM_VF:
> +			num_vf_set = true;
> +			break;
>  		case IFLA_PHYS_PORT_NAME:
>  			errno = 0;
>  			info.port_name = strtol(payload, &end, 0); @@ -
> 867,8 +877,8 @@ struct mlx5_nl_ifindex_data {
>  		}
>  		off += RTA_ALIGN(ra->rta_len);
>  	}
> -	info.master = switch_id_set && !port_name_set;
> -	info.representor = switch_id_set && port_name_set;
> +	info.master = switch_id_set && (!port_name_set || num_vf_set);
> +	info.representor = switch_id_set && port_name_set &&
> !num_vf_set;
>  	memcpy(arg, &info, sizeof(info));
>  	return 0;
>  error:
> @@ -896,9 +906,13 @@ struct mlx5_nl_ifindex_data {
>  	struct {
>  		struct nlmsghdr nh;
>  		struct ifinfomsg info;
> +		struct rtattr rta;
> +		uint32_t extmask;
>  	} req = {
>  		.nh = {
> -			.nlmsg_len = NLMSG_LENGTH(sizeof(req.info)),
> +			.nlmsg_len = NLMSG_LENGTH
> +					(sizeof(req.info) +
> +					 RTA_LENGTH(sizeof(uint32_t))),
>  			.nlmsg_type = RTM_GETLINK,
>  			.nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK,
>  		},
> @@ -906,6 +920,11 @@ struct mlx5_nl_ifindex_data {
>  			.ifi_family = AF_UNSPEC,
>  			.ifi_index = ifindex,
>  		},
> +		.rta = {
> +			.rta_type = IFLA_EXT_MASK,
> +			.rta_len = RTA_LENGTH(sizeof(int32_t)),
> +		},
> +		.extmask = RTE_LE32(1),
>  	};
>  	int ret;
> 
> --
> 1.8.3.1