Re: [libvirt] [PATCH 09/11] Run an RPC protocol over the LXC controller monitor

On Tue, Jul 24, 2012 at 14:22:51 +0100, Daniel P. Berrange wrote: > From: "Daniel P. Berrange" <berrange(a)redhat.com&gt; > > This defines a new RPC protocol to be used between the LXC > controller and the libvirtd LXC driver. There is only a > single RPC message defined thus far, an asynchronous "EXIT" > event that is emitted just before the LXC controller process > exits. This provides the LXC driver with details about how > the container shutdown - normally, or abnormally (crashed), > thus allowing the driver to emit better libvirt events. > > Emitting the event in the LXC controller requires a few > little tricks with the RPC service. Simply calling the > virNetServiceClientSendMessage does not work, since this > merely queues the message for asynchronous processing. > In addition the main event loop is no longer running at > the point the event is emitted, so no I/O is processed. > > Thus after invoking virNetServiceClientSendMessage it is > necessary to mark the client as being in "delayed close" > mode. Then the event loop is run again, until the client > completes its close - this happens only after the queued > message has been fully transmitted. The final complexity > is that it is not safe to run virNetServerQuit() from the > client close callback, since that is invoked from a > context where the server is locked. Thus a zero-second > timer is used to trigger shutdown of the event loop, > causing the controller to finally exit. > > * src/Makefile.am: Add rules for generating RPC protocol > files and dispatch methods > * src/lxc/lxc_controller.c: Emit an RPC event immediately > before exiting > * src/lxc/lxc_domain.h: Record the shutdown reason > given by the controller > * src/lxc/lxc_monitor.c, src/lxc/lxc_monitor.h: Register > RPC program and event handler. Add callback to let > driver receive EXIT event. > * src/lxc/lxc_process.c: Use monitor exit event to decide > what kind of domain event to emit > * src/lxc/lxc_protocol.x: Define wire protocol for LXC > controller monitor. > > Signed-off-by: Daniel P. Berrange <berrange(a)redhat.com&gt; > --- > .gitignore | 4 ++ > src/Makefile.am | 50 +++++++++++++++++++ > src/lxc/lxc_controller.c | 125 +++++++++++++++++++++++++++++++++++++++++++++- > src/lxc/lxc_domain.h | 1 + > src/lxc/lxc_monitor.c | 41 +++++++++++++++ > src/lxc/lxc_monitor.h | 6 +++ > src/lxc/lxc_process.c | 27 ++++++++++ > src/lxc/lxc_protocol.x | 21 ++++++++ > 8 files changed, 274 insertions(+), 1 deletion(-) > create mode 100644 src/lxc/lxc_protocol.x > > diff --git a/.gitignore b/.gitignore > index b4cbb5f..e4b3932 100644 > --- a/.gitignore > +++ b/.gitignore > @@ -105,6 +105,10 @@ > /src/locking/qemu-sanlock.conf > /src/locking/test_libvirt_sanlock.aug > /src/lxc/test_libvirtd_lxc.aug > +/src/lxc/lxc_controller_dispatch.h > +/src/lxc/lxc_monitor_dispatch.h > +/src/lxc/lxc_protocol.c > +/src/lxc/lxc_protocol.h > /src/qemu/test_libvirtd_qemu.aug > /src/remote/*_client_bodies.h > /src/remote/*_protocol.[ch] > diff --git a/src/Makefile.am b/src/Makefile.am > index 492ce73..44da1fa 100644 > --- a/src/Makefile.am > +++ b/src/Makefile.am > @@ -347,7 +347,55 @@ if WITH_XEN_INOTIFY > XEN_DRIVER_SOURCES += xen/xen_inotify.c xen/xen_inotify.h > endif > > +EXTRA_DIST += \ > + dtrace2systemtap.pl \ > + rpc/gendispatch.pl \ > + rpc/genprotocol.pl \ > + rpc/gensystemtap.pl \ > + rpc/virnetprotocol.x \ > + rpc/virkeepaliveprotocol.x Did you want to move this EXTRA_DIST part and copied it instead? I don't see the corresponding - lines.

> + > +LXC_PROTOCOL_GENERATED = \ > + $(srcdir)/lxc/lxc_protocol.h \ > + $(srcdir)/lxc/lxc_protocol.c \ > + $(NULL) Did you add $(NULL) because you want to be able to add new entries here without the need append '\' to the last line or is there another reason for it?