Re: [dpdk-dev] [PATCH 1/2] net/vhost: support TSO disabling

[Maxime Coquelin <maxime.coquelin@redhat.com>]

On 6/19/19 8:13 AM, Noa Ezra wrote:
> TSO (TCP Segmentation Offload) is enabled by default on vhost.
> Add the ability to disable TSO on vhost.
> The user should also disable the feature on the virtual machine's xml.
> 
> Signed-off-by: Noa Ezra <noae@mellanox.com>
> Reviewed-by: Matan Azrad <matan@mellanox.com>
> ---
>  doc/guides/nics/vhost.rst         |  5 +++++
>  drivers/net/vhost/rte_eth_vhost.c | 30 +++++++++++++++++++++++++++---
>  2 files changed, 32 insertions(+), 3 deletions(-)
> 
> diff --git a/doc/guides/nics/vhost.rst b/doc/guides/nics/vhost.rst
> index 23f2e87..8cfda4d 100644
> --- a/doc/guides/nics/vhost.rst
> +++ b/doc/guides/nics/vhost.rst
> @@ -76,6 +76,11 @@ The user can specify below arguments in `--vdev` option.
>      It is used to enable postcopy live-migration support in vhost library.
>      (Default: 0 (disabled))
>  
> +#.  ``tso``:
> +
> +    It is used to disable tso support in vhost library.
> +    (Default: 1 (enabled))
> +
>  Vhost PMD event handling
>  ------------------------
>  
> diff --git a/drivers/net/vhost/rte_eth_vhost.c b/drivers/net/vhost/rte_eth_vhost.c
> index b2cda04..a38c235 100644
> --- a/drivers/net/vhost/rte_eth_vhost.c
> +++ b/drivers/net/vhost/rte_eth_vhost.c
> @@ -31,6 +31,7 @@
>  #define ETH_VHOST_DEQUEUE_ZERO_COPY	"dequeue-zero-copy"
>  #define ETH_VHOST_IOMMU_SUPPORT		"iommu-support"
>  #define ETH_VHOST_POSTCOPY_SUPPORT	"postcopy-support"
> +#define ETH_VHOST_VIRTIO_NET_F_HOST_TSO "tso"
>  #define VHOST_MAX_PKT_BURST 32
>  
>  static const char *valid_arguments[] = {
> @@ -40,6 +41,7 @@
>  	ETH_VHOST_DEQUEUE_ZERO_COPY,
>  	ETH_VHOST_IOMMU_SUPPORT,
>  	ETH_VHOST_POSTCOPY_SUPPORT,
> +	ETH_VHOST_VIRTIO_NET_F_HOST_TSO,
>  	NULL
>  };
>  
> @@ -1200,7 +1202,8 @@ struct vhost_xstats_name_off {
>  
>  static int
>  eth_dev_vhost_create(struct rte_vdev_device *dev, char *iface_name,
> -	int16_t queues, const unsigned int numa_node, uint64_t flags)
> +	int16_t queues, const unsigned int numa_node, uint64_t flags,
> +	uint64_t disable_flags)
>  {
>  	const char *name = rte_vdev_device_name(dev);
>  	struct rte_eth_dev_data *data;
> @@ -1272,6 +1275,11 @@ struct vhost_xstats_name_off {
>  	if (rte_vhost_driver_register(iface_name, flags))
>  		goto error;
>  
> +	if (disable_flags) {
> +		if (rte_vhost_driver_disable_features(iface_name, disable_flags))
> +			goto error;
> +	}
> +
>  	if (rte_vhost_driver_callback_register(iface_name, &vhost_ops) < 0) {
>  		VHOST_LOG(ERR, "Can't register callbacks\n");
>  		goto error;
> @@ -1334,10 +1342,12 @@ struct vhost_xstats_name_off {
>  	char *iface_name;
>  	uint16_t queues;
>  	uint64_t flags = 0;
> +	uint64_t disable_flags = 0;
>  	int client_mode = 0;
>  	int dequeue_zero_copy = 0;
>  	int iommu_support = 0;
>  	int postcopy_support = 0;
> +	int tso = 1;
>  	struct rte_eth_dev *eth_dev;
>  	const char *name = rte_vdev_device_name(dev);
>  
> @@ -1419,11 +1429,24 @@ struct vhost_xstats_name_off {
>  			flags |= RTE_VHOST_USER_POSTCOPY_SUPPORT;
>  	}
>  
> +	if (rte_kvargs_count(kvlist, ETH_VHOST_VIRTIO_NET_F_HOST_TSO) == 1) {
> +		ret = rte_kvargs_process(kvlist,
> +				ETH_VHOST_VIRTIO_NET_F_HOST_TSO,
> +				&open_int, &tso);
> +		if (ret < 0)
> +			goto out_free;
> +
> +		if (tso == 0) {
> +			disable_flags |= (1ULL << VIRTIO_NET_F_HOST_TSO4);
> +			disable_flags |= (1ULL << VIRTIO_NET_F_HOST_TSO6);
> +		}
> +	}
> +
>  	if (dev->device.numa_node == SOCKET_ID_ANY)
>  		dev->device.numa_node = rte_socket_id();
>  
>  	eth_dev_vhost_create(dev, iface_name, queues, dev->device.numa_node,
> -		flags);
> +		flags, disable_flags);
>  
>  out_free:
>  	rte_kvargs_free(kvlist);
> @@ -1470,7 +1493,8 @@ struct vhost_xstats_name_off {
>  	"client=<0|1> "
>  	"dequeue-zero-copy=<0|1> "
>  	"iommu-support=<0|1> "
> -	"postcopy-support=<0|1>");
> +	"postcopy-support=<0|1> "
> +	"tso=<0|1>");
>  
>  RTE_INIT(vhost_init_log)
>  {
> 

With changing the default to disabled:
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>

Do you want me to do the change while applying or you prefer sending the
v2?

Thanks,
Maxime