Re: [dpdk-dev] [PATCH v2 2/2] net/virtio: add link speed devarg

[Adrian Moreno <amorenoz@redhat.com>]

On 1/20/20 6:05 PM, Ivan Dyukov wrote:
> Some applications like pktgen use link_speed to calculate
> transmit rate. It limits outcome traffic to hardcoded 10G.
> 
> This patch adds link_speed devarg which allows to configure
> link_speed of virtio device.
> 
> Signed-off-by: Ivan Dyukov <i.dyukov@samsung.com>
> ---
>  drivers/net/virtio/virtio_ethdev.c | 101 ++++++++++++++++++++++++-----
>  drivers/net/virtio/virtio_pci.h    |   1 +
>  2 files changed, 85 insertions(+), 17 deletions(-)
> 

Hi Ivan,

IMHO, this new option deserves being documented in doc/guides/nics/virtio.rst.

Otherwise it looks good to me.

Thank you.
Adrian
> diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
> index 22323d9a5..5ef3c11a7 100644
> --- a/drivers/net/virtio/virtio_ethdev.c
> +++ b/drivers/net/virtio/virtio_ethdev.c
> @@ -45,6 +45,10 @@ static int virtio_dev_promiscuous_enable(struct rte_eth_dev *dev);
>  static int virtio_dev_promiscuous_disable(struct rte_eth_dev *dev);
>  static int virtio_dev_allmulticast_enable(struct rte_eth_dev *dev);
>  static int virtio_dev_allmulticast_disable(struct rte_eth_dev *dev);
> +static uint32_t virtio_dev_speed_capa_get(uint32_t link_speed);
> +static int virtio_dev_devargs_parse(struct rte_devargs *devargs,
> +	int *vdpa,
> +	uint32_t *link_speed);
>  static int virtio_dev_info_get(struct rte_eth_dev *dev,
>  				struct rte_eth_dev_info *dev_info);
>  static int virtio_dev_link_update(struct rte_eth_dev *dev,
> @@ -1861,6 +1865,7 @@ int
>  eth_virtio_dev_init(struct rte_eth_dev *eth_dev)
>  {
>  	struct virtio_hw *hw = eth_dev->data->dev_private;
> +	uint32_t link_speed = ETH_SPEED_NUM_10G;
>  	int ret;
>  
>  	if (sizeof(struct virtio_net_hdr_mrg_rxbuf) > RTE_PKTMBUF_HEADROOM) {
> @@ -1886,7 +1891,11 @@ eth_virtio_dev_init(struct rte_eth_dev *eth_dev)
>  
>  		return 0;
>  	}
> -
> +	ret = virtio_dev_devargs_parse(eth_dev->device->devargs,
> +		 NULL, &link_speed);
> +	if (ret < 0)
> +		return ret;
> +	hw->link_speed = link_speed;
>  	/*
>  	 * Pass the information to the rte_eth_dev_close() that it should also
>  	 * release the private port resources.
> @@ -1953,6 +1962,14 @@ eth_virtio_dev_uninit(struct rte_eth_dev *eth_dev)
>  
>  	return 0;
>  }
> +#define VIRTIO_ARG_LINK_SPEED "link_speed"
> +#define VIRTIO_ARG_VDPA       "vdpa"
> +
> +static const char * const valid_args[] = {
> +	VIRTIO_ARG_LINK_SPEED,
> +	VIRTIO_ARG_VDPA,
> +	NULL
> +};
>  
>  static int vdpa_check_handler(__rte_unused const char *key,
>  		const char *value, void *ret_val)
> @@ -1965,33 +1982,84 @@ static int vdpa_check_handler(__rte_unused const char *key,
>  	return 0;
>  }
>  
> +
> +static uint32_t
> +virtio_dev_speed_capa_get(uint32_t link_speed)
> +{
> +	switch (link_speed) {
> +	case ETH_SPEED_NUM_10G:
> +		return ETH_LINK_SPEED_10G;
> +	case ETH_SPEED_NUM_20G:
> +		return ETH_LINK_SPEED_20G;
> +	case ETH_SPEED_NUM_25G:
> +		return ETH_LINK_SPEED_25G;
> +	case ETH_SPEED_NUM_40G:
> +		return ETH_LINK_SPEED_40G;
> +	case ETH_SPEED_NUM_50G:
> +		return ETH_LINK_SPEED_50G;
> +	case ETH_SPEED_NUM_56G:
> +		return ETH_LINK_SPEED_56G;
> +	case ETH_SPEED_NUM_100G:
> +		return ETH_LINK_SPEED_100G;
> +	default:
> +		return 0;
> +	}
> +}
> +
> +static int link_speed_handler(const char *key __rte_unused,
> +		const char *value, void *ret_val)
> +{
> +	uint32_t val;
> +	if (!value || !ret_val)
> +		return -EINVAL;
> +	val = strtoul(value, NULL, 0);
> +	/* validate input */
> +	if (virtio_dev_speed_capa_get(val) == 0)
> +		return -EINVAL;
> +	*(uint32_t *)ret_val = val;
> +
> +	return 0;
> +}
> +
> +
>  static int
> -virtio_dev_devargs_parse(struct rte_devargs *devargs, int *vdpa)
> +virtio_dev_devargs_parse(struct rte_devargs *devargs, int *vdpa,
> +	uint32_t *link_speed)
>  {
>  	struct rte_kvargs *kvlist;
> -	const char *key = "vdpa";
>  	int ret = 0;
>  
>  	if (devargs == NULL)
>  		return 0;
>  
> -	kvlist = rte_kvargs_parse(devargs->args, NULL);
> -	if (kvlist == NULL)
> +	kvlist = rte_kvargs_parse(devargs->args, valid_args);
> +	if (kvlist == NULL) {
> +		PMD_INIT_LOG(ERR, "error when parsing param");
>  		return 0;
> -
> -	if (!rte_kvargs_count(kvlist, key))
> -		goto exit;
> -
> -	if (vdpa) {
> +	}
> +	if (vdpa && rte_kvargs_count(kvlist, VIRTIO_ARG_VDPA) == 1) {
>  		/* vdpa mode selected when there's a key-value pair:
>  		 * vdpa=1
>  		 */
> -		ret = rte_kvargs_process(kvlist, key,
> +		ret = rte_kvargs_process(kvlist, VIRTIO_ARG_VDPA,
>  				vdpa_check_handler, vdpa);
> -		if (ret  < 0)
> +		if (ret  < 0) {
> +			PMD_INIT_LOG(ERR, "error to parse %s",
> +				VIRTIO_ARG_VDPA);
>  			goto exit;
> +		}
> +	}
> +	if (link_speed &&
> +		 rte_kvargs_count(kvlist, VIRTIO_ARG_LINK_SPEED) == 1) {
> +		ret = rte_kvargs_process(kvlist,
> +					VIRTIO_ARG_LINK_SPEED,
> +					link_speed_handler, link_speed);
> +		if (ret < 0) {
> +			PMD_INIT_LOG(ERR, "error to parse %s",
> +					VIRTIO_ARG_LINK_SPEED);
> +			goto exit;
> +		}
>  	}
> -
>  
>  exit:
>  	rte_kvargs_free(kvlist);
> @@ -2004,7 +2072,7 @@ static int eth_virtio_pci_probe(struct rte_pci_driver *pci_drv __rte_unused,
>  	int vdpa = 0;
>  	int ret = 0;
>  
> -	ret = virtio_dev_devargs_parse(pci_dev->device.devargs, &vdpa);
> +	ret = virtio_dev_devargs_parse(pci_dev->device.devargs, &vdpa, NULL);
>  	if (ret < 0) {
>  		PMD_DRV_LOG(ERR,
>  			"devargs parsing is failed");
> @@ -2386,7 +2454,7 @@ virtio_dev_link_update(struct rte_eth_dev *dev, __rte_unused int wait_to_complet
>  
>  	memset(&link, 0, sizeof(link));
>  	link.link_duplex = ETH_LINK_FULL_DUPLEX;
> -	link.link_speed  = ETH_SPEED_NUM_10G;
> +	link.link_speed  = hw->link_speed;
>  	link.link_autoneg = ETH_LINK_FIXED;
>  
>  	if (!hw->started) {
> @@ -2441,8 +2509,7 @@ virtio_dev_info_get(struct rte_eth_dev *dev, struct rte_eth_dev_info *dev_info)
>  {
>  	uint64_t tso_mask, host_features;
>  	struct virtio_hw *hw = dev->data->dev_private;
> -
> -	dev_info->speed_capa = ETH_LINK_SPEED_10G; /* fake value */
> +	dev_info->speed_capa = virtio_dev_speed_capa_get(hw->link_speed);
>  
>  	dev_info->max_rx_queues =
>  		RTE_MIN(hw->max_queue_pairs, VIRTIO_MAX_RX_QUEUES);
> diff --git a/drivers/net/virtio/virtio_pci.h b/drivers/net/virtio/virtio_pci.h
> index a38cb45ad..688eda914 100644
> --- a/drivers/net/virtio/virtio_pci.h
> +++ b/drivers/net/virtio/virtio_pci.h
> @@ -253,6 +253,7 @@ struct virtio_hw {
>  	uint16_t    port_id;
>  	uint8_t     mac_addr[RTE_ETHER_ADDR_LEN];
>  	uint32_t    notify_off_multiplier;
> +	uint32_t    link_speed;  /* link speed in MB */
>  	uint8_t     *isr;
>  	uint16_t    *notify_base;
>  	struct virtio_pci_common_cfg *common_cfg;
>