From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:49113) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eqxzB-0006R5-FD for qemu-devel@nongnu.org; Wed, 28 Feb 2018 04:25:20 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eqxzA-00046N-Be for qemu-devel@nongnu.org; Wed, 28 Feb 2018 04:25:17 -0500 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:54504 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1eqxzA-000467-4E for qemu-devel@nongnu.org; Wed, 28 Feb 2018 04:25:16 -0500 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id B8167EB704 for ; Wed, 28 Feb 2018 09:25:15 +0000 (UTC) Date: Wed, 28 Feb 2018 09:25:11 +0000 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Message-ID: <20180228092511.GG31550@redhat.com> Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= References: <20180228050633.7410-1-peterx@redhat.com> <20180228050633.7410-8-peterx@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20180228050633.7410-8-peterx@redhat.com> Subject: Re: [Qemu-devel] [PATCH 07/14] qio/chardev: update net listener gcontext List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Peter Xu Cc: qemu-devel@nongnu.org, Paolo Bonzini , Juan Quintela , Markus Armbruster , =?utf-8?Q?Marc-Andr=C3=A9?= Lureau , Stefan Hajnoczi , "Dr . David Alan Gilbert" On Wed, Feb 28, 2018 at 01:06:26PM +0800, Peter Xu wrote: > TCP chardevs can be using QIO network listeners working in the > background when in listening mode. However the network listeners are > always running in main context. This can race with chardevs that are > running in non-main contexts. > > To solve this: firstly introduce qio_net_listener_set_context() to allow > caller to set gcontext for network listeners. Then call it in > tcp_chr_update_read_handler(), with the newly cached gcontext. > > It's fairly straightforward after we have introduced some net listener > helper functions - basically we unregister the GSources and add them > back with the correct context. > > Signed-off-by: Peter Xu > --- > chardev/char-socket.c | 9 +++++++++ > include/io/net-listener.h | 12 ++++++++++++ > io/net-listener.c | 7 +++++++ > 3 files changed, 28 insertions(+) > > diff --git a/chardev/char-socket.c b/chardev/char-socket.c > index 43a2cc2c1c..8f0935cd15 100644 > --- a/chardev/char-socket.c > +++ b/chardev/char-socket.c > @@ -559,6 +559,15 @@ static void tcp_chr_update_read_handler(Chardev *chr) > { > SocketChardev *s = SOCKET_CHARDEV(chr); > > + if (s->listener) { > + /* > + * It's possible that chardev context is changed in > + * qemu_chr_be_update_read_handlers(). Reset it for QIO net > + * listener if there is. > + */ > + qio_net_listener_set_context(s->listener, chr->gcontext); > + } > + > if (!s->connected) { > return; > } > diff --git a/include/io/net-listener.h b/include/io/net-listener.h > index 566be283b3..39dede9d6f 100644 > --- a/include/io/net-listener.h > +++ b/include/io/net-listener.h > @@ -106,6 +106,18 @@ int qio_net_listener_open_sync(QIONetListener *listener, > SocketAddress *addr, > Error **errp); > > +/** > + * qio_net_listener_set_context: > + * @listener: the net listener object > + * @context: the context that we'd like to bind the sources to > + * > + * This helper does not do anything but moves existing net listener > + * sources from the old one to the new one. It can be seen as a > + * no-operation if there is no listening source at all. > + */ > +void qio_net_listener_set_context(QIONetListener *listener, > + GMainContext *context); I don't think this is a good design. The GMainContext should be provided to the qio_net_listener_set_client_func method immediately, not updated after the fact 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 :|