Re: [dpdk-dev] [PATCH v3 1/2] net/virtio: add vhost-user protocol features support

[Adrian Moreno <amorenoz@redhat.com>]

On 7/3/20 10:40 AM, Xia, Chenbo wrote:
> Hi Adrian,
> 
>> -----Original Message-----
>> From: Adrian Moreno <amorenoz@redhat.com>
>> Sent: Thursday, July 2, 2020 3:44 PM
>> To: dev@dpdk.org
>> Cc: Xia, Chenbo <chenbo.xia@intel.com>; Wang, Zhihong
>> <zhihong.wang@intel.com>; Wang, Xiao W <xiao.w.wang@intel.com>; Yigit,
>> Ferruh <ferruh.yigit@intel.com>; maxime.coquelin@redhat.com
>> Subject: [PATCH v3 1/2] net/virtio: add vhost-user protocol features support
>>
>> From: Maxime Coquelin <maxime.coquelin@redhat.com>
>>
>> This patch adds support for Vhost-user protocol features.
>> It is required to support protocol features that were not in
>> initial Vhost-user specification, such as reply-ack, MTU...
>>
>> Also, this patch prevents Virtio multiqueue feature negotiation
>> if the slave does not support MQ protocol feature as stated
>> in Vhost-user specification:
>> "The multiple queues feature is supported only when the protocol
>> feature ``VHOST_USER_PROTOCOL_F_MQ`` (bit 0) is set."
>>
>> Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
>> ---
>>  drivers/net/virtio/virtio_user/vhost.h        |  9 +++++
>>  drivers/net/virtio/virtio_user/vhost_user.c   |  5 +++
>>  .../net/virtio/virtio_user/virtio_user_dev.c  | 39 ++++++++++++++++++-
>>  .../net/virtio/virtio_user/virtio_user_dev.h  |  3 ++
>>  drivers/net/virtio/virtio_user_ethdev.c       | 19 +++++++++
>>  5 files changed, 73 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/net/virtio/virtio_user/vhost.h
>> b/drivers/net/virtio/virtio_user/vhost.h
>> index 1e784e58e..9ace1a90c 100644
>> --- a/drivers/net/virtio/virtio_user/vhost.h
>> +++ b/drivers/net/virtio/virtio_user/vhost.h
>> @@ -44,6 +44,15 @@ struct vhost_vring_addr {
>>  	uint64_t log_guest_addr;
>>  };
> 
> [snip]
> 
>> @@ -446,6 +455,10 @@ virtio_user_dev_init(struct virtio_user_dev *dev, char
>> *path, int queues,
>>  		return -1;
>>  	}
>>
>> +	if (!is_vhost_user_by_type(dev->path))
>> +		dev->unsupported_features |=
>> +			(1ULL << VHOST_USER_F_PROTOCOL_FEATURES);
>> +
>>  	if (!dev->is_server) {
>>  		if (dev->ops->send_request(dev, VHOST_USER_SET_OWNER,
>>  					   NULL) < 0) {
>> @@ -460,6 +473,26 @@ virtio_user_dev_init(struct virtio_user_dev *dev, char
>> *path, int queues,
>>  				     strerror(errno));
>>  			return -1;
>>  		}
>> +
>> +
>> +		if (dev->device_features &
>> +				(1ULL <<
>> VHOST_USER_F_PROTOCOL_FEATURES)) {
>> +			if (dev->ops->send_request(dev,
>> +
>> 	VHOST_USER_GET_PROTOCOL_FEATURES,
>> +					&protocol_features))
>> +				return -1;
>> +
>> +			dev->protocol_features &= protocol_features;
>> +
>> +			if (dev->ops->send_request(dev,
>> +
>> 	VHOST_USER_SET_PROTOCOL_FEATURES,
>> +						&dev->protocol_features))
>> +				return -1;
>> +
>> +			if (!(dev->protocol_features &
>> +						(1ULL <<
>> VHOST_USER_PROTOCOL_F_MQ)))
>> +				dev->unsupported_features |= (1ull <<
>> VIRTIO_NET_F_MQ);
>> +		}
>>  	} else {
>>  		/* We just pretend vhost-user can support all these features.
>>  		 * Note that this could be problematic that if some feature is
>> @@ -469,6 +502,8 @@ virtio_user_dev_init(struct virtio_user_dev *dev, char
>> *path, int queues,
>>  		dev->device_features = VIRTIO_USER_SUPPORTED_FEATURES;
>>  	}
>>
>> +
>> +
>>  	if (!mrg_rxbuf)
>>  		dev->unsupported_features |= (1ull <<
>> VIRTIO_NET_F_MRG_RXBUF);
>>
>> diff --git a/drivers/net/virtio/virtio_user/virtio_user_dev.h
>> b/drivers/net/virtio/virtio_user/virtio_user_dev.h
>> index 3b6b6065a..56e638f8a 100644
>> --- a/drivers/net/virtio/virtio_user/virtio_user_dev.h
>> +++ b/drivers/net/virtio/virtio_user/virtio_user_dev.h
>> @@ -40,6 +40,9 @@ struct virtio_user_dev {
>>  	uint64_t	device_features; /* supported features by device */
>>  	uint64_t	frontend_features; /* enabled frontend features */
>>  	uint64_t	unsupported_features; /* unsupported features mask
>> */
>> +	uint64_t	protocol_features; /* negotiated protocol features
>> +					    * (Vhost-user only)
>> +					    */
>>  	uint8_t		status;
>>  	uint16_t	port_id;
>>  	uint8_t		mac_addr[RTE_ETHER_ADDR_LEN];
>> diff --git a/drivers/net/virtio/virtio_user_ethdev.c
>> b/drivers/net/virtio/virtio_user_ethdev.c
>> index 798f191c3..ccb5a18e2 100644
>> --- a/drivers/net/virtio/virtio_user_ethdev.c
>> +++ b/drivers/net/virtio/virtio_user_ethdev.c
>> @@ -68,6 +68,7 @@ virtio_user_server_reconnect(struct virtio_user_dev *dev)
>>  	int connectfd;
>>  	struct rte_eth_dev *eth_dev = &rte_eth_devices[dev->port_id];
>>  	struct virtio_hw *hw = eth_dev->data->dev_private;
>> +	uint64_t protocol_features;
>>
>>  	connectfd = accept(dev->listenfd, NULL, NULL);
>>  	if (connectfd < 0)
>> @@ -81,6 +82,24 @@ virtio_user_server_reconnect(struct virtio_user_dev *dev)
>>  		return -1;
>>  	}
>>
>> +	if (dev->device_features &
>> +			(1ULL << VHOST_USER_F_PROTOCOL_FEATURES)) {
>> +		if (dev->ops->send_request(dev,
>> +
>> 	VHOST_USER_GET_PROTOCOL_FEATURES,
>> +					&protocol_features))
>> +			return -1;
>> +
>> +		dev->protocol_features &= protocol_features;
>> +
>> +		if (dev->ops->send_request(dev,
>> +
>> 	VHOST_USER_SET_PROTOCOL_FEATURES,
>> +					&dev->protocol_features))
>> +			return -1;
>> +	}
>> +
>> +	if (!(dev->protocol_features & (1ULL <<
>> VHOST_USER_PROTOCOL_F_MQ)))
>> +		dev->unsupported_features |= (1ull << VIRTIO_NET_F_MQ);
>> +
> 
> Should this 'if' be put into above '{}' ? This should be under the condition that
> VHOST_USER_F_PROTOCOL_FEATURES is supported, right?  Like the code
> change in 'virtio_user_dev_init'.
> 
You're right. I'll re-send
Thanks


> Thanks,
> Chenbo
> 
>>  	dev->device_features |= dev->frontend_features;
>>
>>  	/* umask vhost-user unsupported features */
>> --
>> 2.26.2
> 

-- 
Adrián Moreno