Re: [PATCH 07/10] drm/tests: Add test for drm_framebuffer_init()

[Carlos <gcarlos@xxxxxxxxxxx>]

Hi Maíra,

On 9/8/23 5:22 PM, Maira Canal wrote:
> Hi Carlos,
>
> On 9/4/23 14:41, Carlos wrote:
> > Hi Maíra,
> >
> > On 8/26/23 11:16, Maíra Canal wrote:
> > > Hi Carlos,
> > >
> > > On 8/25/23 13:11, Carlos Eduardo Gallo Filho wrote:
> > > > Add a single KUnit test case for the drm_framebuffer_init function.
> > > >
> > > > Signed-off-by: Carlos Eduardo Gallo Filho <gcarlos@xxxxxxxxxxx>
> > > > ---
> > > >   drivers/gpu/drm/tests/drm_framebuffer_test.c | 52 
> > > > ++++++++++++++++++++
> > > >   1 file changed, 52 insertions(+)
> > > >
> > > > diff --git a/drivers/gpu/drm/tests/drm_framebuffer_test.c 
> > > > b/drivers/gpu/drm/tests/drm_framebuffer_test.c
> > > > index 3d14d35b4c4d..50d88bf3fa65 100644
> > > > --- a/drivers/gpu/drm/tests/drm_framebuffer_test.c
> > > > +++ b/drivers/gpu/drm/tests/drm_framebuffer_test.c
> > > > @@ -557,8 +557,60 @@ static void drm_test_framebuffer_lookup(struct 
> > > > kunit *test)
> > > >       KUNIT_EXPECT_NULL(test, fb2);
> > > >   }
> > > >   +static void drm_test_framebuffer_init(struct kunit *test)
> > > > +{
> > > > +    struct drm_mock *mock = test->priv;
> > > > +    struct drm_device *dev = &mock->dev;
> > > > +    struct drm_device wrong_drm = { };
> > > > +    struct drm_format_info format = { };
> > > > +    struct drm_framebuffer fb1 = { .dev = dev, .format = &format };
> > > > +    struct drm_framebuffer *fb2;
> > > > +    struct drm_framebuffer_funcs funcs = { };
> > > > +    int ret;
> > > > +
> > > > +    /* Fails if fb->dev doesn't point to the drm_device passed on 
> > > > first arg */
> > > > +    fb1.dev = &wrong_drm;
> > > > +    ret = drm_framebuffer_init(dev, &fb1, &funcs);
> > > > +    KUNIT_EXPECT_EQ(test, ret, -EINVAL);
> > > > +    fb1.dev = dev;
> > > > +
> > > > +    /* Fails if fb.format isn't set */
> > > > +    fb1.format = NULL;
> > > > +    ret = drm_framebuffer_init(dev, &fb1, &funcs);
> > > > +    KUNIT_EXPECT_EQ(test, ret, -EINVAL);
> > > > +    fb1.format = &format;
> > > > +
> > > > +    ret = drm_framebuffer_init(dev, &fb1, &funcs);
> > > > +    KUNIT_EXPECT_EQ(test, ret, 0);
> > > > +
> > > > +    /*
> > > > +     * Check if fb->funcs is actually set to the 
> > > > drm_framebuffer_funcs
> > > > +     * passed to it
> > > > +     */
> > > > +    KUNIT_EXPECT_PTR_EQ(test, fb1.funcs, &funcs);
> > > > +
> > > > +    /* The fb->comm must be set to the current running process */
> > > > +    KUNIT_EXPECT_STREQ(test, fb1.comm, current->comm);
> > > > +
> > > > +    /* The fb->base must be successfully initialized */
> > > > +    KUNIT_EXPECT_EQ(test, fb1.base.id, 1);
> > > > +    KUNIT_EXPECT_EQ(test, fb1.base.type, DRM_MODE_OBJECT_FB);
> > > > +    KUNIT_EXPECT_EQ(test, kref_read(&fb1.base.refcount), 1);
> > > > +    KUNIT_EXPECT_PTR_EQ(test, fb1.base.free_cb, 
> > > > &drm_framebuffer_free);
>
> BTW I believe we should also make sure that dev->mode_config.num_fb was
> incremented by 1.
Isn't that already tested below? Since the start value for
dev->mode_config.num_fb is 0, by expecting it to be 1 seems
to test that it's being incremented by 1. Or what are you suggesting
it to let it more explicit?
> > > > +
> > > > +    /* Checks if the fb is really published and findable */
> > > > +    fb2 = drm_framebuffer_lookup(dev, NULL, fb1.base.id);
> > > > +    KUNIT_EXPECT_PTR_EQ(test, fb2, &fb1);
> > > > +
> > > > +    /* There must be just that one fb initialized */
> > > > +    KUNIT_EXPECT_EQ(test, dev->mode_config.num_fb, 1);
> > > > +    KUNIT_EXPECT_PTR_EQ(test, dev->mode_config.fb_list.prev, 
> > > > &fb1.head);
> > > > +    KUNIT_EXPECT_PTR_EQ(test, dev->mode_config.fb_list.next, 
> > > > &fb1.head);
> > >
> > > Shouldn't we clean the framebuffer object?
> > What did you mean by "clean"? Firstly I supposed that it would be about
> > freeing some dynamically allocated frambuffer, but it's statically
> > allocated, so I believe it isn't what you are meaning. Is there some
> > collateral effect I'm not taking into account?
>
> I was talking about calling the function `drm_framebuffer_cleanup()`.
Would you explain why we should need that here? Since the drm_device
(and that fb, of course) is destroyed after the test, do we need to
worry about this?

Thanks,
Carlos

> Best Regards,
> - Maíra
>
> > Thanks,
> > Carlos
> >
> > > Best Regards,
> > > - Maíra
> > >
> > > > +}
> > > > +
> > > >   static struct kunit_case drm_framebuffer_tests[] = {
> > > >       KUNIT_CASE(drm_test_framebuffer_cleanup),
> > > > +    KUNIT_CASE(drm_test_framebuffer_init),
> > > >       KUNIT_CASE(drm_test_framebuffer_lookup),
> > > > KUNIT_CASE(drm_test_framebuffer_modifiers_not_supported),
> > > > KUNIT_CASE_PARAM(drm_test_framebuffer_check_src_coords, 
> > > > check_src_coords_gen_params),