Re: [PATCH v3 13/33] block/nbd: introduce nbd_client_connection_release()

[Roman Kagan]

On Fri, Apr 16, 2021 at 11:08:51AM +0300, Vladimir Sementsov-Ogievskiy wrote:
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> ---
>  block/nbd.c | 43 ++++++++++++++++++++++++++-----------------
>  1 file changed, 26 insertions(+), 17 deletions(-)
> 
> diff --git a/block/nbd.c b/block/nbd.c
> index 21a4039359..8531d019b2 100644
> --- a/block/nbd.c
> +++ b/block/nbd.c
> @@ -118,7 +118,7 @@ typedef struct BDRVNBDState {
>      NBDClientConnection *conn;
>  } BDRVNBDState;
>  
> -static void nbd_free_connect_thread(NBDClientConnection *conn);
> +static void nbd_client_connection_release(NBDClientConnection *conn);
>  static int nbd_establish_connection(BlockDriverState *bs, SocketAddress 
> *saddr,
>                                      Error **errp);
>  static coroutine_fn QIOChannelSocket *
> @@ -130,20 +130,9 @@ static void nbd_yank(void *opaque);
>  static void nbd_clear_bdrvstate(BlockDriverState *bs)
>  {
>      BDRVNBDState *s = (BDRVNBDState *)bs->opaque;
> -    NBDClientConnection *conn = s->conn;
> -    bool do_free;
> -
> -    qemu_mutex_lock(&conn->mutex);
> -    if (conn->running) {
> -        conn->detached = true;
> -    }
> -    do_free = !conn->running && !conn->detached;
> -    qemu_mutex_unlock(&conn->mutex);
>  
> -    /* the runaway thread will clean it up itself */
> -    if (do_free) {
> -        nbd_free_connect_thread(conn);
> -    }
> +    nbd_client_connection_release(s->conn);
> +    s->conn = NULL;
>  
>      yank_unregister_instance(BLOCKDEV_YANK_INSTANCE(bs->node_name));
>  
> @@ -365,7 +354,7 @@ nbd_client_connection_new(const SocketAddress *saddr)
>      return conn;
>  }
>  
> -static void nbd_free_connect_thread(NBDClientConnection *conn)
> +static void nbd_client_connection_do_free(NBDClientConnection *conn)
>  {
>      if (conn->sioc) {
>          qio_channel_close(QIO_CHANNEL(conn->sioc), NULL);
> @@ -379,8 +368,8 @@ static void nbd_free_connect_thread(NBDClientConnection 
> *conn)
>  static void *connect_thread_func(void *opaque)
>  {
>      NBDClientConnection *conn = opaque;
> +    bool do_free;
>      int ret;
> -    bool do_free = false;
>  

This hunk belongs in patch 8.

Roman.

>      conn->sioc = qio_channel_socket_new();
>  
> @@ -405,12 +394,32 @@ static void *connect_thread_func(void *opaque)
>      qemu_mutex_unlock(&conn->mutex);
>  
>      if (do_free) {
> -        nbd_free_connect_thread(conn);
> +        nbd_client_connection_do_free(conn);
>      }
>  
>      return NULL;
>  }
>  
> +static void nbd_client_connection_release(NBDClientConnection *conn)
> +{
> +    bool do_free;
> +
> +    if (!conn) {
> +        return;
> +    }
> +
> +    qemu_mutex_lock(&conn->mutex);
> +    if (conn->running) {
> +        conn->detached = true;
> +    }
> +    do_free = !conn->running && !conn->detached;
> +    qemu_mutex_unlock(&conn->mutex);
> +
> +    if (do_free) {
> +        nbd_client_connection_do_free(conn);
> +    }
> +}
> +
>  /*
>   * Get a new connection in context of @conn:
>   *   if thread is running, wait for completion
> -- 
> 2.29.2
>