Re: [PATCH v3 21/33] qemu-socket: pass monitor link to socket_get_fd directly

[Daniel P . Berrangé]

On Fri, Apr 16, 2021 at 11:08:59AM +0300, Vladimir Sementsov-Ogievskiy wrote:
> Detecting monitor by current coroutine works bad when we are not in
> coroutine context. And that's exactly so in nbd reconnect code, where
> qio_channel_socket_connect_sync() is called from thread.
> 
> Add a possibility to pass monitor by hand, to be used in the following
> commit.
> 
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> ---
>  include/io/channel-socket.h    | 20 ++++++++++++++++++++
>  include/qemu/sockets.h         |  2 +-
>  io/channel-socket.c            | 17 +++++++++++++----
>  tests/unit/test-util-sockets.c | 16 ++++++++--------
>  util/qemu-sockets.c            | 10 +++++-----
>  5 files changed, 47 insertions(+), 18 deletions(-)
> 
> diff --git a/include/io/channel-socket.h b/include/io/channel-socket.h
> index e747e63514..6d0915420d 100644
> --- a/include/io/channel-socket.h
> +++ b/include/io/channel-socket.h
> @@ -78,6 +78,23 @@ qio_channel_socket_new_fd(int fd,
>                            Error **errp);
>  
>  
> +/**
> + * qio_channel_socket_connect_sync_mon:
> + * @ioc: the socket channel object
> + * @addr: the address to connect to
> + * @mon: current monitor. If NULL, it will be detected by
> + *       current coroutine.
> + * @errp: pointer to a NULL-initialized error object
> + *
> + * Attempt to connect to the address @addr. This method
> + * will run in the foreground so the caller will not regain
> + * execution control until the connection is established or
> + * an error occurs.
> + */
> +int qio_channel_socket_connect_sync_mon(QIOChannelSocket *ioc,
> +                                        SocketAddress *addr,
> +                                        Monitor *mon,
> +                                        Error **errp);

I don't really like exposing the concept of the QEMU monitor in
the IO layer APIs. IMHO these ought to remain completely separate
subsystems from the API pov, and we ought to fix this problem by
making monitor_cur() work better in the scenario required.

Regards,
Daniel
-- 
|: https://berrange.com      -o-    https://www.flickr.com/photos/dberrange :|
|: https://libvirt.org         -o-            https://fstop138.berrange.com :|
|: https://entangle-photo.org    -o-    https://www.instagram.com/dberrange :|