On 3/25/23 06:35, David Gow wrote:
On Fri, 24 Mar 2023 at 18:17, Matti Vaittinen <mazziesaccount@xxxxxxxxx> wrote:
On 3/24/23 12:05, Matti Vaittinen wrote:
On 3/24/23 11:52, David Gow wrote:
On Fri, 24 Mar 2023 at 14:51, Matti Vaittinen
<mazziesaccount@xxxxxxxxx> wrote:
On 3/24/23 08:34, David Gow wrote:
On Fri, 24 Mar 2023 at 14:11, Matti Vaittinen
<mazziesaccount@xxxxxxxxx> wrote:
I think that sounds like a good strategy for now, and we can work on a
set of 'generic helpers' which have an associated bus and struct
kunit_device in the meantime. If we can continue to use
root_device_register until those are ready, that'd be very convenient.
Would it be a tiny bit more acceptable if we did add a very simple:
#define kunit_root_device_register(name) root_device_register(name)
#define kunit_root_device_unregister(dev) root_device_unregister(dev)
to include/kunit/device.h (or somesuch)
This should help us later to at least spot the places where
root_device_[un]register() is abused and (potentially mass-)covert them
to use the proper helpers when they're available.
Great idea.
The code I've been playing with has the following in
include/kunit/device.h:
/* Register a new device against a KUnit test. */
struct device *kunit_device_register(struct kunit *test, const char
*name);
/* Unregister a device created by kunit_device_register() early (i.e.,
before test cleanup). */
void kunit_device_unregister(struct kunit *test, struct device *dev);
If we used the same names, and just forwarded them to
root_device_register() and root_device_unregister() for now
(discarding the struct kunit pointer), then I expect we could just
swap out the implementation to gain the extra functionality.
There's one thing though. If the goal is to do a direct replacement and
if automatic device deletion upon test completion / test abort is
planned - then it should be there also for these initial wrappers.
Yeah, that's an excellent point. It's a pretty subtle change in
behaviour to suddenly introduce that, so changing it behind the scenes
is probably unwise.
If these wrappers don't yet include the automatic device clean-up - then
it probably makes more sense to just do the kunit_root_device_* defines
because the tests are likely to need removing the explicit device
clean-ups when proper APIs are finished.
I sent out my prototype implementation of this here, which does do the
automatic cleanup:
https://lore.kernel.org/linux-kselftest/20230325043104.3761770-1-davidgow@xxxxxxxxxx/T/#mf797239a8bce11630875fdf60aab9ed627add1f0
It's probably overkill to squeeze into your patch series, though,
given it also adds and uses a whole new kunit_defer() API.
Thanks for letting me know. I did also prepare this commit yesterday:
https://github.com/M-Vaittinen/linux/commit/b784a90f8cc64ff83e802ec818e662fae1d0c264
It does use the existing kunit resources for clean-up. I am not sure if
it is worth a shot or should I just drop it and use the root-device API
for now. Any educated opinions on that? :)
Yours,
-- Matti
--
Matti Vaittinen
Linux kernel developer at ROHM Semiconductors
Oulu Finland
~~ When things go utterly wrong vim users can always type :help! ~~
