On Thu, May 31, 2018 at 09:23:24AM +0100, Stefan Hajnoczi wrote: > On Thu, May 31, 2018 at 12:11:47PM +0800, Peter Xu wrote: > > On Wed, May 30, 2018 at 05:35:52PM +0100, Stefan Hajnoczi wrote: > > > On Tue, May 29, 2018 at 01:57:53PM +0800, Peter Xu wrote: > > > > Instead, use a dynamic function to detect which clock we'll use. The > > > > problem is that the old code will let monitor initialization depends on > > > > qtest_enabled(). After this change, we don't have such a dependency any > > > > more. > > > > > > There is a hidden dependency: > > > > > > monitor_get_clock() returns the wrong value before main() has > > > processed command-line arguments. > > > > To be more explicit: > > > > monitor_get_clock() returns the wrong value before accelerator is > > correctly setup (in configure_accelerator()). > > > > Since the only thing that matters here is whether we're using the > > qtest accelerator. > > > > > > > > Where is the guarantee that monitor_get_clock() is never called too > > > early? > > > > You are right, there is no guarantee except from programming POV. > > It's only used in: > > > > monitor_qapi_event_queue > > monitor_qapi_event_handler > > > > These two functions will never be called until accelerator is setup. > > > > > > > > At the least, monitor_get_clock() should call abort(3) if invoked too > > > early. Even better would be an interface that cannot be used > > > incorrectly. > > > > Maybe then I should export the accel_initialised variable in > > configure_accelerator() and then I assert with that. But that'll > > further expand the series a bit. > > > > Or, I can also mention above in the commit message to explain that a > > bit. > > Documentation is okay, but please do it in the code, not the commit > message. That way anyone looking at monitor_get_clock() will be aware > of the constraint.
Sure. -- Peter Xu
