在 2019/1/14 下午8:36, Markus Armbruster 写道:
Fei Li <lifei1...@126.com> writes:
Just to make sure about how to do the cleanup. I notice that in
device_set_realized(),
the current code does not call "dc->unrealize(dev, NULL);" when dc->realize()
fails.
Sorry that I am still uncertain.. I guess the code below I pasted was
misleading,
actually I want to stress the *dc->unrealize() is not called when
dc->realize() fails*
and the incomplete below "goto fail" does not include the dc->unrealize(),
but instead the dc->unrealize() is included in later child_realize_fail:
& post_realize_fail:.
Emm, IMHO, I think when dc->realize() fails, the dc->unrealize() is
either should be
called in the common function: device_set_realized() in a unified way,
that is
if (local_err != NULL) {
+ if (dc->unrealize) {
+ dc->unrealize(dev, local_err);
+ }
goto fail;
}
or do the unrealize() locally for each device earlier when dc->realize()
fails.
But I checked several dc->realize() function, they did not call unrealize()
when fails. Besides, it may mean verbose code if unrealize() locally.
Thus I think the above way is the right way to do the cleanup when
realize() fails.
if (dc->realize) {
dc->realize(dev, &local_err);
}
if (local_err != NULL) {
goto fail;
}
Is this on purpose? (Maybe due to some devices' realize() do their own cleanup
when fails? Sorry for the unsure, it is such a common function that I did not
check all. :( ) Or else, I prefer to do the cleanup in a unified manner, e.g. call
"dc->unrealize(dev, NULL);" which is the pci_qdev_unrealize() for pci devices.
Yes, this is on purpose.
When a realize() method fails, it must revert everything it has done so
far. Results in sane "either succeed completely, or fail and do
nothing" semantics.
Have a nice day, thanks
Fei
