Re: [PATCH v2] lib/vhost: add flag for async connection in client mode

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

On 4/17/24 11:15, Ушков Даниил wrote:
> This patch introduces a new flag RTE_VHOST_USER_ASYNC_CONNECT,
> which in combination with the flag RTE_VHOST_USER_CLIENT makes
> rte_vhost_driver_start connect asynchronously to the vhost server.
> 
> Signed-off-by: Ушков Даниил <udav@mts.ru>
> ---
> Fixes:
> 1. Fix warning about the name in signature.
> 2. Fix warning about coding style.
> 
> P.S.
> Is it ok that name is not in ascii?

I think it has to be, Thomas do you confirm?

> Sorry, it could be hard to change it now.
> 
>   lib/vhost/rte_vhost.h |  1 +
>   lib/vhost/socket.c    | 28 ++++++++++++++++------------
>   2 files changed, 17 insertions(+), 12 deletions(-)
> 
> diff --git a/lib/vhost/rte_vhost.h b/lib/vhost/rte_vhost.h
> index db92f05344..b0434c4b8d 100644
> --- a/lib/vhost/rte_vhost.h
> +++ b/lib/vhost/rte_vhost.h
> @@ -41,6 +41,7 @@ extern "C" {
>   #define RTE_VHOST_USER_ASYNC_COPY	(1ULL << 7)
>   #define RTE_VHOST_USER_NET_COMPLIANT_OL_FLAGS	(1ULL << 8)
>   #define RTE_VHOST_USER_NET_STATS_ENABLE	(1ULL << 9)
> +#define RTE_VHOST_USER_ASYNC_CONNECT	(1ULL << 10)
>   
>   /* Features. */
>   #ifndef VIRTIO_NET_F_GUEST_ANNOUNCE
> diff --git a/lib/vhost/socket.c b/lib/vhost/socket.c
> index 96b3ab5595..c681d53abb 100644
> --- a/lib/vhost/socket.c
> +++ b/lib/vhost/socket.c
> @@ -45,6 +45,7 @@ struct vhost_user_socket {
>   	bool async_copy;
>   	bool net_compliant_ol_flags;
>   	bool stats_enabled;
> +	bool async_connect;
>   
>   	/*
>   	 * The "supported_features" indicates the feature bits the
> @@ -533,21 +534,23 @@ vhost_user_start_client(struct vhost_user_socket *vsocket)
>   	const char *path = vsocket->path;
>   	struct vhost_user_reconnect *reconn;
>   
> -	ret = vhost_user_connect_nonblock(vsocket->path, fd, (struct sockaddr *)&vsocket->un,
> -					  sizeof(vsocket->un));
> -	if (ret == 0) {
> -		vhost_user_add_connection(fd, vsocket);
> -		return 0;
> -	}
> +	if (!vsocket->async_connect || !vsocket->reconnect) {
> +		ret = vhost_user_connect_nonblock(vsocket->path, fd,
> +			(struct sockaddr *)&vsocket->un, sizeof(vsocket->un));
> +		if (ret == 0) {
> +			vhost_user_add_connection(fd, vsocket);
> +			return 0;
> +		}
>   
> -	VHOST_CONFIG_LOG(path, WARNING, "failed to connect: %s", strerror(errno));
> +		VHOST_CONFIG_LOG(path, WARNING, "failed to connect: %s", strerror(errno));
>   
> -	if (ret == -2 || !vsocket->reconnect) {
> -		close(fd);
> -		return -1;
> -	}
> +		if (ret == -2 || !vsocket->reconnect) {
> +			close(fd);
> +			return -1;
> +		}
>   
> -	VHOST_CONFIG_LOG(path, INFO, "reconnecting...");
> +		VHOST_CONFIG_LOG(path, INFO, "reconnecting...");
> +	}
>   	reconn = malloc(sizeof(*reconn));
>   	if (reconn == NULL) {
>   		VHOST_CONFIG_LOG(path, ERR, "failed to allocate memory for reconnect");
> @@ -930,6 +933,7 @@ rte_vhost_driver_register(const char *path, uint64_t flags)
>   	vsocket->async_copy = flags & RTE_VHOST_USER_ASYNC_COPY;
>   	vsocket->net_compliant_ol_flags = flags & RTE_VHOST_USER_NET_COMPLIANT_OL_FLAGS;
>   	vsocket->stats_enabled = flags & RTE_VHOST_USER_NET_STATS_ENABLE;
> +	vsocket->async_connect = flags & RTE_VHOST_USER_ASYNC_CONNECT;
>   	if (vsocket->is_vduse)
>   		vsocket->iommu_support = true;
>   	else