Re: [libvirt] [PATCH v2 4/4] qemu: remove pointless connect retry logic in agent

When the agent code was first introduced back in commit c160ce3316852a797d7b06b4ee101233866e69a9 Author: Daniel P. Berrange <berrange(a)redhat.com&gt; Date: Wed Oct 5 18:31:54 2011 +0100 QEMU guest agent support there was code that would loop and retry the connection when opening the agent socket. At this time, the only thing done in between the opening of the monitor socket & opening of the agent socket was a call to set the monitor capabilities. This was a no-op on non-QMP versions, so in theory there could be a race which let us connect to the monitor while the agent socket was still not created by QEMU. In the modern world, however, we long ago mandated the use of QMP for managing QEMU, so we're guaranteed to have a set capabilities QMP call. Once we've seen a reply to this, we're guaranteed that QEMU has fully initialized all backends and is in its event loop. We can thus be sure the QEMU agent socket is present and don't need to retry connections to it, even without having the chardev FD passing feature. Signed-off-by: Daniel P. Berrangé <berrange(a)redhat.com&gt; --- src/qemu/qemu_agent.c | 84 +++++---------------------------------------------- 1 file changed, 7 insertions(+), 77 deletions(-)