On Wed, Nov 15, 2017 at 10:21:16AM +0000, Stefan Hajnoczi wrote:
> On Mon, Nov 06, 2017 at 05:46:43PM +0800, Peter Xu wrote:
> > + /*
> > + * Try a time-consuming command, following by a OOB command, make
> > + * sure we get OOB command before the time-consuming one (which is
> > + * run in the parser).
> > + *
> > + * When writting up this test script, the only command that
> > + * support OOB is migrate-incoming. It's not the best command to
> > + * test OOB but we don't really have a choice here. We will check
> > + * arriving order but not command errors, which does not really
> > + * matter to us.
> > + */
> > + qmp_async("{ 'execute': 'dump-guest-memory',"
> > + " 'arguments': { 'paging': true, "
> > + " 'protocol': 'file:/dev/null' }, "
> > + " 'id': 'time-consuming-cmd'}");
> > + qmp_async("{ 'execute': 'migrate-incoming', "
> > + " 'control': { 'run-oob': true }, "
> > + " 'id': 'oob-cmd' }");
> > +
> > + /* Ignore all events. Wait for 2 acks */
> > + while (acks < 2) {
> > + resp = qmp_receive();
> > + if (qdict_haskey(resp, "event")) {
> > + /* Skip possible events */
> > + continue;
> > + }
> > + cmd_id = qdict_get_str(resp, "id");
> > + if (acks == 0) {
> > + /* Need to receive OOB response first */
> > + g_assert_cmpstr(cmd_id, ==, "oob-cmd");
> > + } else if (acks == 1) {
> > + g_assert_cmpstr(cmd_id, ==, "time-consuming-cmd");
> > + }
> > + acks++;
> > + }
>
> This test is non-deterministic. The dump-guest-memory command could
> complete first on a fast machine.
>
> On a slow machine this test might take a long time...
>
> Please introduce a test command that is deterministic. For example,
> when 'x-oob-test' is invoked without 'run-oob': true it waits until
> invoked again, this time with 'run-oob': true.
Yes this sounds good.
>
> We have similar interfaces in the block layer for controlling the order
> in which parallel I/O requests are processed. This allows test cases to
> deterministically take specific code paths.
It's great to know that I can create a command to test it. That
should be much easier. Thanks,
--
Peter Xu
