Re: [PATCH v2] Input: tests: add test to cover all input_grab_device() function

From: Javier Martinez Canillas
Date: Wed May 17 2023 - 13:25:59 EST


Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx> writes:

Hello Dmitry,

> Hi Dana,
>
> On Wed, May 17, 2023 at 06:31:45PM +0300, Dana Elfassy wrote:
>> Currently input_grab_device() isn't covered by any tests
>> Thus, adding a test to cover the cases:
>> 1. The device is grabbed successfully
>> 2. Trying to grab a device that is already grabbed by another input
>> handle
>>
>> Signed-off-by: Dana Elfassy <dangel101@xxxxxxxxx>
>> Tested-by: Javier Martinez Canillas <javierm@xxxxxxxxxx>
>> Reviewed-by: Javier Martinez Canillas <javierm@xxxxxxxxxx>
>> ---
>>
>> Changes in v2:
>> - Use input_put_device() to decrement the refcount increased by get().
>> - Remove unnecessary struct input_handle test_handle variable.
>
> So this tests something different than what patch description states.
> You are testing that there is no "recursive" grabbing happening (an API
> could be designed to allow the same handle grab device several times).
> This is a good and useful test, but you do want to also use 2nd separate
> handle to see that it gets -EBUSY as well. And ideally we should have

That was my fault since v1 had two different handles but since it wasn't
releasing it, didn't add any value really so I asked Dana to just drop it.

> another test verifying that the 2nd handle can successfully grab the
> device once the first handle releases it.
>

That's the correct approach indeed and would make the test more useful.

--
Best regards,

Javier Martinez Canillas
Core Platforms
Red Hat