[Qemu-devel] [PATCH v2 7/9] chardev: tcp: postpone async connection setup

Peter Xu posted 9 patches 7 years, 9 months ago
[Qemu-devel] [PATCH v2 7/9] chardev: tcp: postpone async connection setup
Posted by Peter Xu 7 years, 9 months ago
This patch allows the socket chardev async connection be setup with
non-default gcontext.  We do it by postponing the setup to machine done,
since until then we can know which context we should run the async
operation on.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
---
 chardev/char-socket.c | 17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/chardev/char-socket.c b/chardev/char-socket.c
index 1ce5adad9a..165612845a 100644
--- a/chardev/char-socket.c
+++ b/chardev/char-socket.c
@@ -1004,9 +1004,8 @@ static void qmp_chardev_open_socket(Chardev *chr,
         s->reconnect_time = reconnect;
     }
 
-    if (s->reconnect_time) {
-        tcp_chr_connect_async(chr);
-    } else {
+    /* If reconnect_time is set, will do that in chr_machine_done. */
+    if (!s->reconnect_time) {
         if (s->is_listen) {
             char *name;
             s->listener = qio_net_listener_new();
@@ -1138,6 +1137,17 @@ char_socket_get_connected(Object *obj, Error **errp)
     return s->connected;
 }
 
+static int tcp_chr_machine_done_hook(Chardev *chr)
+{
+    SocketChardev *s = SOCKET_CHARDEV(chr);
+
+    if (s->reconnect_time) {
+        tcp_chr_connect_async(chr);
+    }
+
+    return 0;
+}
+
 static void char_socket_class_init(ObjectClass *oc, void *data)
 {
     ChardevClass *cc = CHARDEV_CLASS(oc);
@@ -1153,6 +1163,7 @@ static void char_socket_class_init(ObjectClass *oc, void *data)
     cc->chr_add_client = tcp_chr_add_client;
     cc->chr_add_watch = tcp_chr_add_watch;
     cc->chr_update_read_handler = tcp_chr_update_read_handler;
+    cc->chr_machine_done = tcp_chr_machine_done_hook;
 
     object_class_property_add(oc, "addr", "SocketAddress",
                               char_socket_get_addr, NULL,
-- 
2.14.3


Re: [Qemu-devel] [PATCH v2 7/9] chardev: tcp: postpone async connection setup
Posted by Daniel P. Berrangé 7 years, 9 months ago
On Tue, Mar 06, 2018 at 01:33:18PM +0800, Peter Xu wrote:
> This patch allows the socket chardev async connection be setup with
> non-default gcontext.  We do it by postponing the setup to machine done,
> since until then we can know which context we should run the async
> operation on.
> 
> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
> Signed-off-by: Peter Xu <peterx@redhat.com>
> ---
>  chardev/char-socket.c | 17 ++++++++++++++---
>  1 file changed, 14 insertions(+), 3 deletions(-)

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>


Regards,
Daniel
-- 
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Re: [Qemu-devel] [PATCH v2 7/9] chardev: tcp: postpone async connection setup
Posted by Marc-André Lureau 7 years, 4 months ago
Hi
On Tue, Mar 6, 2018 at 6:41 AM Peter Xu <peterx@redhat.com> wrote:
>
> This patch allows the socket chardev async connection be setup with
> non-default gcontext.  We do it by postponing the setup to machine done,
> since until then we can know which context we should run the async
> operation on.
>
> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
> Signed-off-by: Peter Xu <peterx@redhat.com>
> ---
>  chardev/char-socket.c | 17 ++++++++++++++---
>  1 file changed, 14 insertions(+), 3 deletions(-)
>
> diff --git a/chardev/char-socket.c b/chardev/char-socket.c
> index 1ce5adad9a..165612845a 100644
> --- a/chardev/char-socket.c
> +++ b/chardev/char-socket.c
> @@ -1004,9 +1004,8 @@ static void qmp_chardev_open_socket(Chardev *chr,
>          s->reconnect_time = reconnect;
>      }
>
> -    if (s->reconnect_time) {
> -        tcp_chr_connect_async(chr);
> -    } else {
> +    /* If reconnect_time is set, will do that in chr_machine_done. */
> +    if (!s->reconnect_time) {
>          if (s->is_listen) {
>              char *name;
>              s->listener = qio_net_listener_new();
> @@ -1138,6 +1137,17 @@ char_socket_get_connected(Object *obj, Error **errp)
>      return s->connected;
>  }
>
> +static int tcp_chr_machine_done_hook(Chardev *chr)
> +{
> +    SocketChardev *s = SOCKET_CHARDEV(chr);
> +
> +    if (s->reconnect_time) {
> +        tcp_chr_connect_async(chr);
> +    }
> +
> +    return 0;
> +}

This patch broke /vhost-user/reconnect test, since it is using
reconnect chardev sockets under a test program, where no machine done
hook exist.

> +
>  static void char_socket_class_init(ObjectClass *oc, void *data)
>  {
>      ChardevClass *cc = CHARDEV_CLASS(oc);
> @@ -1153,6 +1163,7 @@ static void char_socket_class_init(ObjectClass *oc, void *data)
>      cc->chr_add_client = tcp_chr_add_client;
>      cc->chr_add_watch = tcp_chr_add_watch;
>      cc->chr_update_read_handler = tcp_chr_update_read_handler;
> +    cc->chr_machine_done = tcp_chr_machine_done_hook;
>
>      object_class_property_add(oc, "addr", "SocketAddress",
>                                char_socket_get_addr, NULL,
> --
> 2.14.3
>
>


-- 
Marc-André Lureau

Re: [Qemu-devel] [PATCH v2 7/9] chardev: tcp: postpone async connection setup
Posted by Marc-André Lureau 7 years, 4 months ago
Hi
On Thu, Aug 16, 2018 at 7:49 PM Marc-André Lureau
<marcandre.lureau@gmail.com> wrote:
>
> Hi
> On Tue, Mar 6, 2018 at 6:41 AM Peter Xu <peterx@redhat.com> wrote:
> >
> > This patch allows the socket chardev async connection be setup with
> > non-default gcontext.  We do it by postponing the setup to machine done,
> > since until then we can know which context we should run the async
> > operation on.
> >
> > Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
> > Signed-off-by: Peter Xu <peterx@redhat.com>
> > ---
> >  chardev/char-socket.c | 17 ++++++++++++++---
> >  1 file changed, 14 insertions(+), 3 deletions(-)
> >
> > diff --git a/chardev/char-socket.c b/chardev/char-socket.c
> > index 1ce5adad9a..165612845a 100644
> > --- a/chardev/char-socket.c
> > +++ b/chardev/char-socket.c
> > @@ -1004,9 +1004,8 @@ static void qmp_chardev_open_socket(Chardev *chr,
> >          s->reconnect_time = reconnect;
> >      }
> >
> > -    if (s->reconnect_time) {
> > -        tcp_chr_connect_async(chr);
> > -    } else {
> > +    /* If reconnect_time is set, will do that in chr_machine_done. */
> > +    if (!s->reconnect_time) {
> >          if (s->is_listen) {
> >              char *name;
> >              s->listener = qio_net_listener_new();
> > @@ -1138,6 +1137,17 @@ char_socket_get_connected(Object *obj, Error **errp)
> >      return s->connected;
> >  }
> >
> > +static int tcp_chr_machine_done_hook(Chardev *chr)
> > +{
> > +    SocketChardev *s = SOCKET_CHARDEV(chr);
> > +
> > +    if (s->reconnect_time) {
> > +        tcp_chr_connect_async(chr);
> > +    }
> > +
> > +    return 0;
> > +}
>
> This patch broke /vhost-user/reconnect test, since it is using
> reconnect chardev sockets under a test program, where no machine done
> hook exist.
>

What about chardev created after machine done?

> > +
> >  static void char_socket_class_init(ObjectClass *oc, void *data)
> >  {
> >      ChardevClass *cc = CHARDEV_CLASS(oc);
> > @@ -1153,6 +1163,7 @@ static void char_socket_class_init(ObjectClass *oc, void *data)
> >      cc->chr_add_client = tcp_chr_add_client;
> >      cc->chr_add_watch = tcp_chr_add_watch;
> >      cc->chr_update_read_handler = tcp_chr_update_read_handler;
> > +    cc->chr_machine_done = tcp_chr_machine_done_hook;
> >
> >      object_class_property_add(oc, "addr", "SocketAddress",
> >                                char_socket_get_addr, NULL,
> > --
> > 2.14.3
> >
> >
>
>
> --
> Marc-André Lureau



-- 
Marc-André Lureau

Re: [Qemu-devel] [PATCH v2 7/9] chardev: tcp: postpone async connection setup
Posted by Peter Xu 7 years, 4 months ago
On Thu, Aug 16, 2018 at 08:27:40PM +0200, Marc-André Lureau wrote:
> Hi
> On Thu, Aug 16, 2018 at 7:49 PM Marc-André Lureau
> <marcandre.lureau@gmail.com> wrote:
> >
> > Hi
> > On Tue, Mar 6, 2018 at 6:41 AM Peter Xu <peterx@redhat.com> wrote:
> > >
> > > This patch allows the socket chardev async connection be setup with
> > > non-default gcontext.  We do it by postponing the setup to machine done,
> > > since until then we can know which context we should run the async
> > > operation on.
> > >
> > > Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
> > > Signed-off-by: Peter Xu <peterx@redhat.com>
> > > ---
> > >  chardev/char-socket.c | 17 ++++++++++++++---
> > >  1 file changed, 14 insertions(+), 3 deletions(-)
> > >
> > > diff --git a/chardev/char-socket.c b/chardev/char-socket.c
> > > index 1ce5adad9a..165612845a 100644
> > > --- a/chardev/char-socket.c
> > > +++ b/chardev/char-socket.c
> > > @@ -1004,9 +1004,8 @@ static void qmp_chardev_open_socket(Chardev *chr,
> > >          s->reconnect_time = reconnect;
> > >      }
> > >
> > > -    if (s->reconnect_time) {
> > > -        tcp_chr_connect_async(chr);
> > > -    } else {
> > > +    /* If reconnect_time is set, will do that in chr_machine_done. */
> > > +    if (!s->reconnect_time) {
> > >          if (s->is_listen) {
> > >              char *name;
> > >              s->listener = qio_net_listener_new();
> > > @@ -1138,6 +1137,17 @@ char_socket_get_connected(Object *obj, Error **errp)
> > >      return s->connected;
> > >  }
> > >
> > > +static int tcp_chr_machine_done_hook(Chardev *chr)
> > > +{
> > > +    SocketChardev *s = SOCKET_CHARDEV(chr);
> > > +
> > > +    if (s->reconnect_time) {
> > > +        tcp_chr_connect_async(chr);
> > > +    }
> > > +
> > > +    return 0;
> > > +}
> >
> > This patch broke /vhost-user/reconnect test, since it is using
> > reconnect chardev sockets under a test program, where no machine done
> > hook exist.
> >
> 
> What about chardev created after machine done?

Hmm, so binding that with machine done might be problematic...

I'm thinking whether we can do that in ->chr_update_read_handler()
instead.

Btw, is there a short answer on why we disabled the reconnection test
in vhost-user-test?  Could I just verify the problem using:

QTEST_VHOST_USER_FIXME=1 QTEST_QEMU_BINARY=x86_64-softmmu/qemu-system-x86_64 ./tests/vhost-user-test

?  Or any easy way to reproduce/verify the problem?

Regards,

-- 
Peter Xu