[PATCH 3/7] vhost: make use of FD manager init function

[David Marchand]

On Thu, Feb 29, 2024 at 1:25 PM Maxime Coquelin
<maxime.coquelin at redhat.com> wrote:
>
> Instead of statically initialize the fdset, this patch
> converts VDUSE and Vhost-user to use fdset_init() function,
> which now also initialize the mutexes.
>
> This is preliminary rework to hide FDs manager pipe from
> its users.
>
> Signed-off-by: Maxime Coquelin <maxime.coquelin at redhat.com>
> ---
>  lib/vhost/fd_man.c |  9 +++++++--
>  lib/vhost/fd_man.h |  2 +-
>  lib/vhost/socket.c | 11 +++++------
>  lib/vhost/vduse.c  | 14 ++++++--------
>  4 files changed, 19 insertions(+), 17 deletions(-)
>
> diff --git a/lib/vhost/fd_man.c b/lib/vhost/fd_man.c
> index 5dde40e51a..d33036a171 100644
> --- a/lib/vhost/fd_man.c
> +++ b/lib/vhost/fd_man.c
> @@ -96,19 +96,24 @@ fdset_add_fd(struct fdset *pfdset, int idx, int fd,
>         pfd->revents = 0;
>  }
>
> -void
> +int
>  fdset_init(struct fdset *pfdset)
>  {
>         int i;
>
>         if (pfdset == NULL)
> -               return;
> +               return -1;
> +
> +       pthread_mutex_init(&pfdset->fd_mutex, NULL);
> +       pthread_mutex_init(&pfdset->fd_polling_mutex, NULL);

Following patch 1, we are missing init of sync_* variables.


>
>         for (i = 0; i < MAX_FDS; i++) {
>                 pfdset->fd[i].fd = -1;
>                 pfdset->fd[i].dat = NULL;
>         }
>         pfdset->num = 0;
> +
> +       return 0;
>  }
>
>  /**
> diff --git a/lib/vhost/fd_man.h b/lib/vhost/fd_man.h
> index 2517ae5a9b..92d24d8591 100644
> --- a/lib/vhost/fd_man.h
> +++ b/lib/vhost/fd_man.h
> @@ -43,7 +43,7 @@ struct fdset {
>  };
>
>
> -void fdset_init(struct fdset *pfdset);
> +int fdset_init(struct fdset *pfdset);
>
>  int fdset_add(struct fdset *pfdset, int fd,
>         fd_cb rcb, fd_cb wcb, void *dat);
> diff --git a/lib/vhost/socket.c b/lib/vhost/socket.c
> index a2fdac30a4..b544e39be7 100644
> --- a/lib/vhost/socket.c
> +++ b/lib/vhost/socket.c
> @@ -89,12 +89,6 @@ static int create_unix_socket(struct vhost_user_socket *vsocket);
>  static int vhost_user_start_client(struct vhost_user_socket *vsocket);
>
>  static struct vhost_user vhost_user = {
> -       .fdset = {
> -               .fd = { [0 ... MAX_FDS - 1] = {-1, NULL, NULL, NULL, 0} },
> -               .fd_mutex = PTHREAD_MUTEX_INITIALIZER,
> -               .fd_pooling_mutex = PTHREAD_MUTEX_INITIALIZER,
> -               .num = 0
> -       },
>         .vsocket_cnt = 0,
>         .mutex = PTHREAD_MUTEX_INITIALIZER,
>  };
> @@ -1187,6 +1181,11 @@ rte_vhost_driver_start(const char *path)
>                 return vduse_device_create(path, vsocket->net_compliant_ol_flags);
>
>         if (fdset_tid.opaque_id == 0) {
> +               if (fdset_init(&vhost_user.fdset) < 0) {
> +                       VHOST_CONFIG_LOG(path, ERR, "Failed to init Vhost-user fdset");

Nit: other log messages in this function are not consistent wrt
starting with a capital letter.


> +                       return -1;
> +               }
> +
>                 /**
>                  * create a pipe which will be waited by poll and notified to
>                  * rebuild the wait list of poll.
> diff --git a/lib/vhost/vduse.c b/lib/vhost/vduse.c
> index d462428d2c..d83d7b0d7c 100644
> --- a/lib/vhost/vduse.c
> +++ b/lib/vhost/vduse.c
> @@ -31,14 +31,7 @@ struct vduse {
>         struct fdset fdset;
>  };
>
> -static struct vduse vduse = {
> -       .fdset = {
> -               .fd = { [0 ... MAX_FDS - 1] = {-1, NULL, NULL, NULL, 0} },
> -               .fd_mutex = PTHREAD_MUTEX_INITIALIZER,
> -               .fd_pooling_mutex = PTHREAD_MUTEX_INITIALIZER,
> -               .num = 0
> -       },
> -};
> +static struct vduse vduse;
>
>  static bool vduse_events_thread;
>
> @@ -434,6 +427,11 @@ vduse_device_create(const char *path, bool compliant_ol_flags)
>
>         /* If first device, create events dispatcher thread */
>         if (vduse_events_thread == false) {
> +               if (fdset_init(&vduse.fdset) < 0) {
> +                       VHOST_CONFIG_LOG(path, ERR, "Failed to init VDUSE fdset");
> +                       return -1;
> +               }
> +

Nit: idem
+ other log messages use "vduse fdset".


-- 
David Marchand