From: lvroyce <lvroyce(a)linux.vnet.ibm.com&gt; some system call and signal will interrupt poll, making event loop stops and fails to react events and keepalive message from libvirt. adding handling EINTR to poll to make it more robust Signed-off-by: lvroyce <lvroyce(a)linux.vnet.ibm.com&gt; --- examples/domain-events/events-python/event-test.py | 8 +++++++- 1 files changed, 7 insertions(+), 1 deletions(-) diff --git a/examples/domain-events/events-python/event-test.py b/examples/domain-events/events-python/event-test.py index 96dc268..b446c21 100644 --- a/examples/domain-events/events-python/event-test.py +++ b/examples/domain-events/events-python/event-test.py @@ -188,7 +188,13 @@ class virEventLoopPure: sleep = (next - now) / 1000.0 debug("Poll with a sleep of %d" % sleep) - events = self.poll.poll(sleep) + try: + events = self.poll.poll(sleep) + except select.error, e: + self.runningPoll = False + if not e.errno in (errno.EINTR, errno.EAGAIN): + raise + return

On Mon, Jun 18, 2012 at 10:56:26AM +0100, Daniel P. Berrange wrote: > On Mon, Jun 18, 2012 at 05:43:55PM +0800, lvroyce(a)linux.vnet.ibm.com wrote: > > From: lvroyce <lvroyce(a)linux.vnet.ibm.com&gt; > > > > some system call and signal will interrupt poll, > > making event loop stops and fails to react events and keepalive message > > from libvirt. > > adding handling EINTR to poll to make it more robust > > > > Signed-off-by: lvroyce <lvroyce(a)linux.vnet.ibm.com&gt; > > --- > > examples/domain-events/events-python/event-test.py | 8 +++++++- > > 1 files changed, 7 insertions(+), 1 deletions(-) > > > > diff --git a/examples/domain-events/events-python/event-test.py b/examples/domain-events/events-python/event-test.py > > index 96dc268..b446c21 100644 > > --- a/examples/domain-events/events-python/event-test.py > > +++ b/examples/domain-events/events-python/event-test.py > > @@ -188,7 +188,13 @@ class virEventLoopPure: > > sleep = (next - now) / 1000.0 > > > > debug("Poll with a sleep of %d" % sleep) > > - events = self.poll.poll(sleep) > > + try: > > + events = self.poll.poll(sleep) > > + except select.error, e: > > + self.runningPoll = False > > + if not e.errno in (errno.EINTR, errno.EAGAIN): > > + raise > > + return > > It isn't possible for poll() to return EAGAIN according to the > manpage. > > If you remove that errno, then the patch would be ok. Also the > indentation in the except: block is too deep - line it up with > the try: block The same function has another possible exception-raiser: os.read() few lines below, and probably others. How about putting self.runningPoll = False in a "finally" clause opened right after the first self.runningPoll assignment?