RE: [PATCH V4 2/2] gpu/tests/gpu_buddy: Add KUnit test for gpu_buddy_allocated_addr_to_block

> -----Original Message-----
> From: Arunpravin Paneer Selvam <[email protected]>
> Sent: 06 August 2026 16:43
> To: Auld, Matthew <[email protected]>; Upadhyay, Tejas
> <[email protected]>; [email protected]; dri-
> [email protected]
> Subject: Re: [PATCH V4 2/2] gpu/tests/gpu_buddy: Add KUnit test for
> gpu_buddy_allocated_addr_to_block
> 
> 
> 
> On 8/6/2026 3:49 PM, Matthew Auld wrote:
> > On 06/08/2026 10:46, Upadhyay, Tejas wrote:
> >>
> >>
> >>> -----Original Message-----
> >>> From: Auld, Matthew <[email protected]>
> >>> Sent: 06 August 2026 14:31
> >>> To: Upadhyay, Tejas <[email protected]>; intel-
> >>> [email protected]; [email protected]
> >>> Cc: [email protected]
> >>> Subject: Re: [PATCH V4 2/2] gpu/tests/gpu_buddy: Add KUnit test for
> >>> gpu_buddy_allocated_addr_to_block
> >>>
> >>> On 06/08/2026 06:36, Tejas Upadhyay wrote:
> >>>> Add a new KUnit test gpu_test_buddy_addr_to_block() that validates
> >>>> the
> >>>> gpu_buddy_allocated_addr_to_block() helper which traces a address
> >>>> back to its allocated buddy block.
> >>>>
> >>>> The test covers:
> >>>> - Exact address matching returns the correct allocated block
> >>>> - An unallocated address inside the manager should return NULL
> >>>> - An address outside the manager should return -ENXIO
> >>>>
> >>>> v4(MattA):
> >>>> - Add test for unaligned address
> >>>> v3(Sashiko):
> >>>> - remove unused target_addr variable
> >>>> v2(Sashiko):
> >>>> - Drop the mutex and lockdep annotation; standalone KUnit tests do
> >>>>     not register a driver lock.
> >>>>
> >>>> Signed-off-by: Tejas Upadhyay <[email protected]>
> >>>
> >>> Reviewed-by: Matthew Auld <[email protected]>
> >>
> >> Hi Matt,
> >>
> >> Thanks for review. Since I don’t have merge rights on drm-tip, Would
> >> you please help merging this series.
> >
> > I think Arun normally merges these. Arun, any objections? We need this
> > for an upcoming driver feature (patches on the list), so wanted to
> > land this API ahead of time. I don't think this will conflict much
> > with the big rework you were doing.
> No objections. Do you want me to merge the series below into drm-misc-
> next?
> 
> https://patchwork.freedesktop.org/series/171145/

Thanks. Yes, you pointed to the right series.

Tejas
> 
> Regards,
> Arun.
> >
> >>
> >> Tejas
> >>>
> >>>> ---
> >>>>    drivers/gpu/tests/gpu_buddy_test.c | 45
> >>> ++++++++++++++++++++++++++++++
> >>>>    1 file changed, 45 insertions(+)
> >>>>
> >>>> diff --git a/drivers/gpu/tests/gpu_buddy_test.c
> >>>> b/drivers/gpu/tests/gpu_buddy_test.c
> >>>> index 7df5c2ae83bb..04e425eb8bdd 100644
> >>>> --- a/drivers/gpu/tests/gpu_buddy_test.c
> >>>> +++ b/drivers/gpu/tests/gpu_buddy_test.c
> >>>> @@ -1381,6 +1381,50 @@ static void
> >>> gpu_test_buddy_alloc_exceeds_max_order(struct kunit *test)
> >>>>        gpu_buddy_fini(&mm);
> >>>>    }
> >>>>
> >>>> +static void gpu_test_buddy_addr_to_block(struct kunit *test) {
> >>>> +    struct gpu_buddy_block *allocated_block, *found_block;
> >>>> +    LIST_HEAD(allocated_list);
> >>>> +    const u64 test_size = SZ_4M + SZ_2M;
> >>>> +    const u64 alloc_start = SZ_4M;
> >>>> +    const u64 alloc_size = SZ_4K;
> >>>> +    const u64 chunk_size = SZ_4K;
> >>>> +    struct gpu_buddy mm;
> >>>> +
> >>>> +    KUNIT_ASSERT_FALSE_MSG(test, gpu_buddy_init(&mm, test_size,
> >>> chunk_size),
> >>>> +                   "buddy_init failed\n");
> >>>> +
> >>>> +    KUNIT_ASSERT_FALSE_MSG(test, gpu_buddy_alloc_blocks(&mm,
> >>> alloc_start,
> >>>> + alloc_start +
> >>> alloc_size,
> >>>> + alloc_size,
> >>> chunk_size,
> >>>> + &allocated_list, 0),
> >>>> +                   "buddy_alloc failed\n");
> >>>> +
> >>>> +    allocated_block = list_first_entry(&allocated_list, struct
> >>> gpu_buddy_block, link);
> >>>> +    KUNIT_EXPECT_EQ(test, gpu_buddy_block_offset(allocated_block),
> >>> alloc_start);
> >>>> +    KUNIT_EXPECT_EQ(test, gpu_buddy_block_size(&mm,
> >>> allocated_block),
> >>>> +alloc_size);
> >>>> +
> >>>> +    found_block = gpu_buddy_allocated_addr_to_block(&mm,
> >>> alloc_start);
> >>>> +    KUNIT_EXPECT_PTR_EQ(test, found_block, allocated_block);
> >>>> +
> >>>> +    /* Unaligned address inside the allocated block (should
> >>>> resolve to the
> >>> same block) */
> >>>> +    found_block = gpu_buddy_allocated_addr_to_block(&mm,
> >>>> +alloc_start
> >>> + 16);
> >>>> +    KUNIT_EXPECT_PTR_EQ(test, found_block, allocated_block);
> >>>> +
> >>>> +    /* An unallocated address inside the manager should return
> >>>> NULL. */
> >>>> +    found_block = gpu_buddy_allocated_addr_to_block(&mm,
> >>>> +                            alloc_start -
> >>> chunk_size);
> >>>> +    KUNIT_EXPECT_NULL(test, found_block);
> >>>> +
> >>>> +    /* An address outside the manager should return -ENXIO. */
> >>>> +    found_block = gpu_buddy_allocated_addr_to_block(&mm,
> >>>> +test_size);
> >>>> +    KUNIT_EXPECT_EQ(test, PTR_ERR(found_block), -ENXIO);
> >>>> +
> >>>> +    /* 3. Standard inline cleanup flow */
> >>>> +    gpu_buddy_free_list(&mm, &allocated_list, 0);
> >>>> +    gpu_buddy_fini(&mm);
> >>>> +}
> >>>> +
> >>>>    static int gpu_buddy_suite_init(struct kunit_suite *suite)
> >>>>    {
> >>>>        while (!random_seed)
> >>>> @@ -1405,6 +1449,7 @@ static struct kunit_case gpu_buddy_tests[] =
> >>>> {
> >>>>        KUNIT_CASE(gpu_test_buddy_alloc_exceeds_max_order),
> >>>>        KUNIT_CASE(gpu_test_buddy_offset_aligned_allocation),
> >>>> KUNIT_CASE(gpu_test_buddy_subtree_offset_alignment_stress),
> >>>> +    KUNIT_CASE(gpu_test_buddy_addr_to_block),
> >>>>        {}
> >>>>    };
> >>>>
> >>
> >