VM introspection

[RFC PATCH v1 04/26] char-socket: add 'reconnecting' property

Posted by Adalbert Lazăr 5 years, 10 months ago

This is used by the VM introspection object to check if the connection
will be reestablished in case it disconnects from some reason.

The closing of the socket is used by any of the three parties involved,
KVM, the introspection tool and QEMU (eg. on force-reset), to signal
the other parties that the session is over. As such, it is very important
that the socket will reconnect.

CC: "Marc-André Lureau" <marcandre.lureau@redhat.com>
CC: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Adalbert Lazăr <alazar@bitdefender.com>
---
 chardev/char-socket.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/chardev/char-socket.c b/chardev/char-socket.c
index fd0106ab85..22ab242748 100644
--- a/chardev/char-socket.c
+++ b/chardev/char-socket.c
@@ -1492,6 +1492,13 @@ char_socket_get_connected(Object *obj, Error **errp)
     return s->state == TCP_CHARDEV_STATE_CONNECTED;
 }
 
+static bool char_socket_get_reconnecting(Object *obj, Error **errp)
+{
+    SocketChardev *s = SOCKET_CHARDEV(obj);
+
+    return s->reconnect_time > 0;
+}
+
 static int tcp_chr_reconnect_time(Chardev *chr, int secs)
 {
     SocketChardev *s = SOCKET_CHARDEV(chr);
@@ -1528,6 +1535,10 @@ static void char_socket_class_init(ObjectClass *oc, void *data)
 
     object_class_property_add_bool(oc, "connected", char_socket_get_connected,
                                    NULL, &error_abort);
+
+    object_class_property_add_bool(oc, "reconnecting",
+                                   char_socket_get_reconnecting,
+                                   NULL, &error_abort);
 }
 
 static const TypeInfo char_socket_type_info = {

Re: [RFC PATCH v1 04/26] char-socket: add 'reconnecting' property

Posted by Marc-André Lureau 5 years, 10 months ago

Hi

On Wed, Apr 15, 2020 at 3:03 AM Adalbert Lazăr <alazar@bitdefender.com> wrote:
>
> This is used by the VM introspection object to check if the connection
> will be reestablished in case it disconnects from some reason.
>
> The closing of the socket is used by any of the three parties involved,
> KVM, the introspection tool and QEMU (eg. on force-reset), to signal
> the other parties that the session is over. As such, it is very important
> that the socket will reconnect.
>
> CC: "Marc-André Lureau" <marcandre.lureau@redhat.com>
> CC: Paolo Bonzini <pbonzini@redhat.com>
> Signed-off-by: Adalbert Lazăr <alazar@bitdefender.com>
> ---
>  chardev/char-socket.c | 11 +++++++++++
>  1 file changed, 11 insertions(+)
>
> diff --git a/chardev/char-socket.c b/chardev/char-socket.c
> index fd0106ab85..22ab242748 100644
> --- a/chardev/char-socket.c
> +++ b/chardev/char-socket.c
> @@ -1492,6 +1492,13 @@ char_socket_get_connected(Object *obj, Error **errp)
>      return s->state == TCP_CHARDEV_STATE_CONNECTED;
>  }
>
> +static bool char_socket_get_reconnecting(Object *obj, Error **errp)
> +{
> +    SocketChardev *s = SOCKET_CHARDEV(obj);
> +
> +    return s->reconnect_time > 0;
> +}
> +
>  static int tcp_chr_reconnect_time(Chardev *chr, int secs)
>  {
>      SocketChardev *s = SOCKET_CHARDEV(chr);
> @@ -1528,6 +1535,10 @@ static void char_socket_class_init(ObjectClass *oc, void *data)
>
>      object_class_property_add_bool(oc, "connected", char_socket_get_connected,
>                                     NULL, &error_abort);
> +
> +    object_class_property_add_bool(oc, "reconnecting",
> +                                   char_socket_get_reconnecting,
> +                                   NULL, &error_abort);

That may be misleading, as the socket connection may be established
and this will return true if reconnect_time > 0. Why not have a
"reconnect-time" property instead?

>  }
>
>  static const TypeInfo char_socket_type_info = {
>


-- 
Marc-André Lureau

Re: [RFC PATCH v1 04/26] char-socket: add 'reconnecting' property

Posted by Adalbert Lazăr 5 years, 10 months ago

On Wed, 15 Apr 2020 12:46:57 +0200, Marc-André Lureau <marcandre.lureau@gmail.com> wrote:
> Hi
> 
> On Wed, Apr 15, 2020 at 3:03 AM Adalbert Lazăr <alazar@bitdefender.com> wrote:
> >
> > This is used by the VM introspection object to check if the connection
> > will be reestablished in case it disconnects from some reason.
> >
> > The closing of the socket is used by any of the three parties involved,
> > KVM, the introspection tool and QEMU (eg. on force-reset), to signal
> > the other parties that the session is over. As such, it is very important
> > that the socket will reconnect.
> >
> > CC: "Marc-André Lureau" <marcandre.lureau@redhat.com>
> > CC: Paolo Bonzini <pbonzini@redhat.com>
> > Signed-off-by: Adalbert Lazăr <alazar@bitdefender.com>
> > ---
> >  chardev/char-socket.c | 11 +++++++++++
> >  1 file changed, 11 insertions(+)
> >
> > diff --git a/chardev/char-socket.c b/chardev/char-socket.c
> > index fd0106ab85..22ab242748 100644
> > --- a/chardev/char-socket.c
> > +++ b/chardev/char-socket.c
> > @@ -1492,6 +1492,13 @@ char_socket_get_connected(Object *obj, Error **errp)
> >      return s->state == TCP_CHARDEV_STATE_CONNECTED;
> >  }
> >
> > +static bool char_socket_get_reconnecting(Object *obj, Error **errp)
> > +{
> > +    SocketChardev *s = SOCKET_CHARDEV(obj);
> > +
> > +    return s->reconnect_time > 0;
> > +}
> > +
> >  static int tcp_chr_reconnect_time(Chardev *chr, int secs)
> >  {
> >      SocketChardev *s = SOCKET_CHARDEV(chr);
> > @@ -1528,6 +1535,10 @@ static void char_socket_class_init(ObjectClass *oc, void *data)
> >
> >      object_class_property_add_bool(oc, "connected", char_socket_get_connected,
> >                                     NULL, &error_abort);
> > +
> > +    object_class_property_add_bool(oc, "reconnecting",
> > +                                   char_socket_get_reconnecting,
> > +                                   NULL, &error_abort);
> 
> That may be misleading, as the socket connection may be established
> and this will return true if reconnect_time > 0. Why not have a
> "reconnect-time" property instead?
> 

Sure.
Thanks.