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

> -----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.

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),
> >   	{}
> >   };
> >