diff mbox series

drm/tests/drm_buddy: add alloc_contiguous test

Message ID 20240208143618.247048-2-matthew.auld@intel.com (mailing list archive)
State New, archived
Headers show
Series drm/tests/drm_buddy: add alloc_contiguous test | expand

Commit Message

Matthew Auld Feb. 8, 2024, 2:36 p.m. UTC
Sanity check DRM_BUDDY_CONTIGUOUS_ALLOCATION.

References: https://gitlab.freedesktop.org/drm/amd/-/issues/3097
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Arunpravin Paneer Selvam <Arunpravin.PaneerSelvam@amd.com>
Cc: Limonciello <mario.limonciello@amd.com>
Cc: Christian König <christian.koenig@amd.com>
---
 drivers/gpu/drm/tests/drm_buddy_test.c | 89 ++++++++++++++++++++++++++
 1 file changed, 89 insertions(+)

Comments

Paneer Selvam, Arunpravin Feb. 8, 2024, 3:37 p.m. UTC | #1
On 2/8/2024 8:06 PM, Matthew Auld wrote:
> Sanity check DRM_BUDDY_CONTIGUOUS_ALLOCATION.
That's really quick :)

Reviewed-by: Arunpravin Paneer Selvam <Arunpravin.PaneerSelvam@amd.com>

>
> References:https://gitlab.freedesktop.org/drm/amd/-/issues/3097
> Signed-off-by: Matthew Auld<matthew.auld@intel.com>
> Cc: Arunpravin Paneer Selvam<Arunpravin.PaneerSelvam@amd.com>
> Cc: Limonciello<mario.limonciello@amd.com>
> Cc: Christian König<christian.koenig@amd.com>
> ---
>   drivers/gpu/drm/tests/drm_buddy_test.c | 89 ++++++++++++++++++++++++++
>   1 file changed, 89 insertions(+)
>
> diff --git a/drivers/gpu/drm/tests/drm_buddy_test.c b/drivers/gpu/drm/tests/drm_buddy_test.c
> index ea2af6bd9abe..4215d8b5fcf0 100644
> --- a/drivers/gpu/drm/tests/drm_buddy_test.c
> +++ b/drivers/gpu/drm/tests/drm_buddy_test.c
> @@ -8,6 +8,7 @@
>   
>   #include <linux/prime_numbers.h>
>   #include <linux/sched/signal.h>
> +#include <linux/sizes.h>
>   
>   #include <drm/drm_buddy.h>
>   
> @@ -18,6 +19,93 @@ static inline u64 get_size(int order, u64 chunk_size)
>   	return (1 << order) * chunk_size;
>   }
>   
> +static void drm_test_buddy_alloc_contiguous(struct kunit *test)
> +{
> +	u64 mm_size, ps = SZ_4K, i, n_pages, total;
> +	struct drm_buddy_block *block;
> +	struct drm_buddy mm;
> +	LIST_HEAD(left);
> +	LIST_HEAD(middle);
> +	LIST_HEAD(right);
> +	LIST_HEAD(allocated);
> +
> +	mm_size = 16 * 3 * SZ_4K;
> +
> +	KUNIT_EXPECT_FALSE(test, drm_buddy_init(&mm, mm_size, ps));
> +
> +	/*
> +	 * Idea is to fragment the address space by alternating block
> +	 * allocations between three different lists; one for left, middle and
> +	 * right. We can then free a list to simulate fragmentation. In
> +	 * particular we want to exercise the DRM_BUDDY_CONTIGUOUS_ALLOCATION,
> +	 * including the try_harder path.
> +	 */
> +
> +	i = 0;
> +	n_pages = mm_size / ps;
> +	do {
> +		struct list_head *list;
> +		int slot = i % 3;
> +
> +		if (slot == 0)
> +			list = &left;
> +		else if (slot == 1)
> +			list = &middle;
> +		else
> +			list = &right;
> +		KUNIT_ASSERT_FALSE_MSG(test,
> +				       drm_buddy_alloc_blocks(&mm, 0, mm_size,
> +							      ps, ps, list, 0),
> +				       "buddy_alloc hit an error size=%d\n",
> +				       ps);
> +	} while (++i < n_pages);
> +
> +	KUNIT_ASSERT_TRUE_MSG(test, drm_buddy_alloc_blocks(&mm, 0, mm_size,
> +							   3 * ps, ps, &allocated,
> +							   DRM_BUDDY_CONTIGUOUS_ALLOCATION),
> +			       "buddy_alloc didn't error size=%d\n", 3 * ps);
> +
> +	drm_buddy_free_list(&mm, &middle);
> +	KUNIT_ASSERT_TRUE_MSG(test, drm_buddy_alloc_blocks(&mm, 0, mm_size,
> +							   3 * ps, ps, &allocated,
> +							   DRM_BUDDY_CONTIGUOUS_ALLOCATION),
> +			       "buddy_alloc didn't error size=%llu\n", 3 * ps);
> +	KUNIT_ASSERT_TRUE_MSG(test, drm_buddy_alloc_blocks(&mm, 0, mm_size,
> +							   2 * ps, ps, &allocated,
> +							   DRM_BUDDY_CONTIGUOUS_ALLOCATION),
> +			       "buddy_alloc didn't error size=%llu\n", 2 * ps);
> +
> +	drm_buddy_free_list(&mm, &right);
> +	KUNIT_ASSERT_TRUE_MSG(test, drm_buddy_alloc_blocks(&mm, 0, mm_size,
> +							   3 * ps, ps, &allocated,
> +							   DRM_BUDDY_CONTIGUOUS_ALLOCATION),
> +			       "buddy_alloc didn't error size=%llu\n", 3 * ps);
> +	/*
> +	 * At this point we should have enough contiguous space for 2 blocks,
> +	 * however they are never buddies (since we freed middle and right) so
> +	 * will require the try_harder logic to find them.
> +	 */
> +	KUNIT_ASSERT_FALSE_MSG(test, drm_buddy_alloc_blocks(&mm, 0, mm_size,
> +							   2 * ps, ps, &allocated,
> +							   DRM_BUDDY_CONTIGUOUS_ALLOCATION),
> +			       "buddy_alloc hit an error size=%d\n", 2 * ps);
> +
> +	drm_buddy_free_list(&mm, &left);
> +	KUNIT_ASSERT_FALSE_MSG(test, drm_buddy_alloc_blocks(&mm, 0, mm_size,
> +							   3 * ps, ps, &allocated,
> +							   DRM_BUDDY_CONTIGUOUS_ALLOCATION),
> +			       "buddy_alloc hit an error size=%d\n", 3 * ps);
> +
> +	total = 0;
> +	list_for_each_entry(block, &allocated, link)
> +		total += drm_buddy_block_size(&mm, block);
> +
> +	KUNIT_ASSERT_EQ(test, total, ps * 2 + ps * 3);
> +
> +	drm_buddy_free_list(&mm, &allocated);
> +	drm_buddy_fini(&mm);
> +}
> +
>   static void drm_test_buddy_alloc_pathological(struct kunit *test)
>   {
>   	u64 mm_size, size, start = 0;
> @@ -280,6 +368,7 @@ static struct kunit_case drm_buddy_tests[] = {
>   	KUNIT_CASE(drm_test_buddy_alloc_optimistic),
>   	KUNIT_CASE(drm_test_buddy_alloc_pessimistic),
>   	KUNIT_CASE(drm_test_buddy_alloc_pathological),
> +	KUNIT_CASE(drm_test_buddy_alloc_contiguous),
>   	{}
>   };
>
Paneer Selvam, Arunpravin Feb. 12, 2024, 8:23 a.m. UTC | #2
Hi Matthew,

Can I push this test case along with the bug fix patch.

Thanks,
Arun.

On 2/8/2024 8:06 PM, Matthew Auld wrote:
> Sanity check DRM_BUDDY_CONTIGUOUS_ALLOCATION.
>
> References: https://gitlab.freedesktop.org/drm/amd/-/issues/3097
> Signed-off-by: Matthew Auld <matthew.auld@intel.com>
> Cc: Arunpravin Paneer Selvam <Arunpravin.PaneerSelvam@amd.com>
> Cc: Limonciello <mario.limonciello@amd.com>
> Cc: Christian König <christian.koenig@amd.com>
> ---
>   drivers/gpu/drm/tests/drm_buddy_test.c | 89 ++++++++++++++++++++++++++
>   1 file changed, 89 insertions(+)
>
> diff --git a/drivers/gpu/drm/tests/drm_buddy_test.c b/drivers/gpu/drm/tests/drm_buddy_test.c
> index ea2af6bd9abe..4215d8b5fcf0 100644
> --- a/drivers/gpu/drm/tests/drm_buddy_test.c
> +++ b/drivers/gpu/drm/tests/drm_buddy_test.c
> @@ -8,6 +8,7 @@
>   
>   #include <linux/prime_numbers.h>
>   #include <linux/sched/signal.h>
> +#include <linux/sizes.h>
>   
>   #include <drm/drm_buddy.h>
>   
> @@ -18,6 +19,93 @@ static inline u64 get_size(int order, u64 chunk_size)
>   	return (1 << order) * chunk_size;
>   }
>   
> +static void drm_test_buddy_alloc_contiguous(struct kunit *test)
> +{
> +	u64 mm_size, ps = SZ_4K, i, n_pages, total;
> +	struct drm_buddy_block *block;
> +	struct drm_buddy mm;
> +	LIST_HEAD(left);
> +	LIST_HEAD(middle);
> +	LIST_HEAD(right);
> +	LIST_HEAD(allocated);
> +
> +	mm_size = 16 * 3 * SZ_4K;
> +
> +	KUNIT_EXPECT_FALSE(test, drm_buddy_init(&mm, mm_size, ps));
> +
> +	/*
> +	 * Idea is to fragment the address space by alternating block
> +	 * allocations between three different lists; one for left, middle and
> +	 * right. We can then free a list to simulate fragmentation. In
> +	 * particular we want to exercise the DRM_BUDDY_CONTIGUOUS_ALLOCATION,
> +	 * including the try_harder path.
> +	 */
> +
> +	i = 0;
> +	n_pages = mm_size / ps;
> +	do {
> +		struct list_head *list;
> +		int slot = i % 3;
> +
> +		if (slot == 0)
> +			list = &left;
> +		else if (slot == 1)
> +			list = &middle;
> +		else
> +			list = &right;
> +		KUNIT_ASSERT_FALSE_MSG(test,
> +				       drm_buddy_alloc_blocks(&mm, 0, mm_size,
> +							      ps, ps, list, 0),
> +				       "buddy_alloc hit an error size=%d\n",
> +				       ps);
> +	} while (++i < n_pages);
> +
> +	KUNIT_ASSERT_TRUE_MSG(test, drm_buddy_alloc_blocks(&mm, 0, mm_size,
> +							   3 * ps, ps, &allocated,
> +							   DRM_BUDDY_CONTIGUOUS_ALLOCATION),
> +			       "buddy_alloc didn't error size=%d\n", 3 * ps);
> +
> +	drm_buddy_free_list(&mm, &middle);
> +	KUNIT_ASSERT_TRUE_MSG(test, drm_buddy_alloc_blocks(&mm, 0, mm_size,
> +							   3 * ps, ps, &allocated,
> +							   DRM_BUDDY_CONTIGUOUS_ALLOCATION),
> +			       "buddy_alloc didn't error size=%llu\n", 3 * ps);
> +	KUNIT_ASSERT_TRUE_MSG(test, drm_buddy_alloc_blocks(&mm, 0, mm_size,
> +							   2 * ps, ps, &allocated,
> +							   DRM_BUDDY_CONTIGUOUS_ALLOCATION),
> +			       "buddy_alloc didn't error size=%llu\n", 2 * ps);
> +
> +	drm_buddy_free_list(&mm, &right);
> +	KUNIT_ASSERT_TRUE_MSG(test, drm_buddy_alloc_blocks(&mm, 0, mm_size,
> +							   3 * ps, ps, &allocated,
> +							   DRM_BUDDY_CONTIGUOUS_ALLOCATION),
> +			       "buddy_alloc didn't error size=%llu\n", 3 * ps);
> +	/*
> +	 * At this point we should have enough contiguous space for 2 blocks,
> +	 * however they are never buddies (since we freed middle and right) so
> +	 * will require the try_harder logic to find them.
> +	 */
> +	KUNIT_ASSERT_FALSE_MSG(test, drm_buddy_alloc_blocks(&mm, 0, mm_size,
> +							   2 * ps, ps, &allocated,
> +							   DRM_BUDDY_CONTIGUOUS_ALLOCATION),
> +			       "buddy_alloc hit an error size=%d\n", 2 * ps);
> +
> +	drm_buddy_free_list(&mm, &left);
> +	KUNIT_ASSERT_FALSE_MSG(test, drm_buddy_alloc_blocks(&mm, 0, mm_size,
> +							   3 * ps, ps, &allocated,
> +							   DRM_BUDDY_CONTIGUOUS_ALLOCATION),
> +			       "buddy_alloc hit an error size=%d\n", 3 * ps);
> +
> +	total = 0;
> +	list_for_each_entry(block, &allocated, link)
> +		total += drm_buddy_block_size(&mm, block);
> +
> +	KUNIT_ASSERT_EQ(test, total, ps * 2 + ps * 3);
> +
> +	drm_buddy_free_list(&mm, &allocated);
> +	drm_buddy_fini(&mm);
> +}
> +
>   static void drm_test_buddy_alloc_pathological(struct kunit *test)
>   {
>   	u64 mm_size, size, start = 0;
> @@ -280,6 +368,7 @@ static struct kunit_case drm_buddy_tests[] = {
>   	KUNIT_CASE(drm_test_buddy_alloc_optimistic),
>   	KUNIT_CASE(drm_test_buddy_alloc_pessimistic),
>   	KUNIT_CASE(drm_test_buddy_alloc_pathological),
> +	KUNIT_CASE(drm_test_buddy_alloc_contiguous),
>   	{}
>   };
>
Matthew Auld Feb. 12, 2024, 9:12 a.m. UTC | #3
On 12/02/2024 08:23, Arunpravin Paneer Selvam wrote:
> Hi Matthew,
> 
> Can I push this test case along with the bug fix patch.

Sure. Please go ahead.

> 
> Thanks,
> Arun.
> 
> On 2/8/2024 8:06 PM, Matthew Auld wrote:
>> Sanity check DRM_BUDDY_CONTIGUOUS_ALLOCATION.
>>
>> References: https://gitlab.freedesktop.org/drm/amd/-/issues/3097
>> Signed-off-by: Matthew Auld <matthew.auld@intel.com>
>> Cc: Arunpravin Paneer Selvam <Arunpravin.PaneerSelvam@amd.com>
>> Cc: Limonciello <mario.limonciello@amd.com>
>> Cc: Christian König <christian.koenig@amd.com>
>> ---
>>   drivers/gpu/drm/tests/drm_buddy_test.c | 89 ++++++++++++++++++++++++++
>>   1 file changed, 89 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/tests/drm_buddy_test.c 
>> b/drivers/gpu/drm/tests/drm_buddy_test.c
>> index ea2af6bd9abe..4215d8b5fcf0 100644
>> --- a/drivers/gpu/drm/tests/drm_buddy_test.c
>> +++ b/drivers/gpu/drm/tests/drm_buddy_test.c
>> @@ -8,6 +8,7 @@
>>   #include <linux/prime_numbers.h>
>>   #include <linux/sched/signal.h>
>> +#include <linux/sizes.h>
>>   #include <drm/drm_buddy.h>
>> @@ -18,6 +19,93 @@ static inline u64 get_size(int order, u64 chunk_size)
>>       return (1 << order) * chunk_size;
>>   }
>> +static void drm_test_buddy_alloc_contiguous(struct kunit *test)
>> +{
>> +    u64 mm_size, ps = SZ_4K, i, n_pages, total;
>> +    struct drm_buddy_block *block;
>> +    struct drm_buddy mm;
>> +    LIST_HEAD(left);
>> +    LIST_HEAD(middle);
>> +    LIST_HEAD(right);
>> +    LIST_HEAD(allocated);
>> +
>> +    mm_size = 16 * 3 * SZ_4K;
>> +
>> +    KUNIT_EXPECT_FALSE(test, drm_buddy_init(&mm, mm_size, ps));
>> +
>> +    /*
>> +     * Idea is to fragment the address space by alternating block
>> +     * allocations between three different lists; one for left, 
>> middle and
>> +     * right. We can then free a list to simulate fragmentation. In
>> +     * particular we want to exercise the 
>> DRM_BUDDY_CONTIGUOUS_ALLOCATION,
>> +     * including the try_harder path.
>> +     */
>> +
>> +    i = 0;
>> +    n_pages = mm_size / ps;
>> +    do {
>> +        struct list_head *list;
>> +        int slot = i % 3;
>> +
>> +        if (slot == 0)
>> +            list = &left;
>> +        else if (slot == 1)
>> +            list = &middle;
>> +        else
>> +            list = &right;
>> +        KUNIT_ASSERT_FALSE_MSG(test,
>> +                       drm_buddy_alloc_blocks(&mm, 0, mm_size,
>> +                                  ps, ps, list, 0),
>> +                       "buddy_alloc hit an error size=%d\n",
>> +                       ps);
>> +    } while (++i < n_pages);
>> +
>> +    KUNIT_ASSERT_TRUE_MSG(test, drm_buddy_alloc_blocks(&mm, 0, mm_size,
>> +                               3 * ps, ps, &allocated,
>> +                               DRM_BUDDY_CONTIGUOUS_ALLOCATION),
>> +                   "buddy_alloc didn't error size=%d\n", 3 * ps);
>> +
>> +    drm_buddy_free_list(&mm, &middle);
>> +    KUNIT_ASSERT_TRUE_MSG(test, drm_buddy_alloc_blocks(&mm, 0, mm_size,
>> +                               3 * ps, ps, &allocated,
>> +                               DRM_BUDDY_CONTIGUOUS_ALLOCATION),
>> +                   "buddy_alloc didn't error size=%llu\n", 3 * ps);
>> +    KUNIT_ASSERT_TRUE_MSG(test, drm_buddy_alloc_blocks(&mm, 0, mm_size,
>> +                               2 * ps, ps, &allocated,
>> +                               DRM_BUDDY_CONTIGUOUS_ALLOCATION),
>> +                   "buddy_alloc didn't error size=%llu\n", 2 * ps);
>> +
>> +    drm_buddy_free_list(&mm, &right);
>> +    KUNIT_ASSERT_TRUE_MSG(test, drm_buddy_alloc_blocks(&mm, 0, mm_size,
>> +                               3 * ps, ps, &allocated,
>> +                               DRM_BUDDY_CONTIGUOUS_ALLOCATION),
>> +                   "buddy_alloc didn't error size=%llu\n", 3 * ps);
>> +    /*
>> +     * At this point we should have enough contiguous space for 2 
>> blocks,
>> +     * however they are never buddies (since we freed middle and 
>> right) so
>> +     * will require the try_harder logic to find them.
>> +     */
>> +    KUNIT_ASSERT_FALSE_MSG(test, drm_buddy_alloc_blocks(&mm, 0, mm_size,
>> +                               2 * ps, ps, &allocated,
>> +                               DRM_BUDDY_CONTIGUOUS_ALLOCATION),
>> +                   "buddy_alloc hit an error size=%d\n", 2 * ps);
>> +
>> +    drm_buddy_free_list(&mm, &left);
>> +    KUNIT_ASSERT_FALSE_MSG(test, drm_buddy_alloc_blocks(&mm, 0, mm_size,
>> +                               3 * ps, ps, &allocated,
>> +                               DRM_BUDDY_CONTIGUOUS_ALLOCATION),
>> +                   "buddy_alloc hit an error size=%d\n", 3 * ps);
>> +
>> +    total = 0;
>> +    list_for_each_entry(block, &allocated, link)
>> +        total += drm_buddy_block_size(&mm, block);
>> +
>> +    KUNIT_ASSERT_EQ(test, total, ps * 2 + ps * 3);
>> +
>> +    drm_buddy_free_list(&mm, &allocated);
>> +    drm_buddy_fini(&mm);
>> +}
>> +
>>   static void drm_test_buddy_alloc_pathological(struct kunit *test)
>>   {
>>       u64 mm_size, size, start = 0;
>> @@ -280,6 +368,7 @@ static struct kunit_case drm_buddy_tests[] = {
>>       KUNIT_CASE(drm_test_buddy_alloc_optimistic),
>>       KUNIT_CASE(drm_test_buddy_alloc_pessimistic),
>>       KUNIT_CASE(drm_test_buddy_alloc_pathological),
>> +    KUNIT_CASE(drm_test_buddy_alloc_contiguous),
>>       {}
>>   };
>
diff mbox series

Patch

diff --git a/drivers/gpu/drm/tests/drm_buddy_test.c b/drivers/gpu/drm/tests/drm_buddy_test.c
index ea2af6bd9abe..4215d8b5fcf0 100644
--- a/drivers/gpu/drm/tests/drm_buddy_test.c
+++ b/drivers/gpu/drm/tests/drm_buddy_test.c
@@ -8,6 +8,7 @@ 
 
 #include <linux/prime_numbers.h>
 #include <linux/sched/signal.h>
+#include <linux/sizes.h>
 
 #include <drm/drm_buddy.h>
 
@@ -18,6 +19,93 @@  static inline u64 get_size(int order, u64 chunk_size)
 	return (1 << order) * chunk_size;
 }
 
+static void drm_test_buddy_alloc_contiguous(struct kunit *test)
+{
+	u64 mm_size, ps = SZ_4K, i, n_pages, total;
+	struct drm_buddy_block *block;
+	struct drm_buddy mm;
+	LIST_HEAD(left);
+	LIST_HEAD(middle);
+	LIST_HEAD(right);
+	LIST_HEAD(allocated);
+
+	mm_size = 16 * 3 * SZ_4K;
+
+	KUNIT_EXPECT_FALSE(test, drm_buddy_init(&mm, mm_size, ps));
+
+	/*
+	 * Idea is to fragment the address space by alternating block
+	 * allocations between three different lists; one for left, middle and
+	 * right. We can then free a list to simulate fragmentation. In
+	 * particular we want to exercise the DRM_BUDDY_CONTIGUOUS_ALLOCATION,
+	 * including the try_harder path.
+	 */
+
+	i = 0;
+	n_pages = mm_size / ps;
+	do {
+		struct list_head *list;
+		int slot = i % 3;
+
+		if (slot == 0)
+			list = &left;
+		else if (slot == 1)
+			list = &middle;
+		else
+			list = &right;
+		KUNIT_ASSERT_FALSE_MSG(test,
+				       drm_buddy_alloc_blocks(&mm, 0, mm_size,
+							      ps, ps, list, 0),
+				       "buddy_alloc hit an error size=%d\n",
+				       ps);
+	} while (++i < n_pages);
+
+	KUNIT_ASSERT_TRUE_MSG(test, drm_buddy_alloc_blocks(&mm, 0, mm_size,
+							   3 * ps, ps, &allocated,
+							   DRM_BUDDY_CONTIGUOUS_ALLOCATION),
+			       "buddy_alloc didn't error size=%d\n", 3 * ps);
+
+	drm_buddy_free_list(&mm, &middle);
+	KUNIT_ASSERT_TRUE_MSG(test, drm_buddy_alloc_blocks(&mm, 0, mm_size,
+							   3 * ps, ps, &allocated,
+							   DRM_BUDDY_CONTIGUOUS_ALLOCATION),
+			       "buddy_alloc didn't error size=%llu\n", 3 * ps);
+	KUNIT_ASSERT_TRUE_MSG(test, drm_buddy_alloc_blocks(&mm, 0, mm_size,
+							   2 * ps, ps, &allocated,
+							   DRM_BUDDY_CONTIGUOUS_ALLOCATION),
+			       "buddy_alloc didn't error size=%llu\n", 2 * ps);
+
+	drm_buddy_free_list(&mm, &right);
+	KUNIT_ASSERT_TRUE_MSG(test, drm_buddy_alloc_blocks(&mm, 0, mm_size,
+							   3 * ps, ps, &allocated,
+							   DRM_BUDDY_CONTIGUOUS_ALLOCATION),
+			       "buddy_alloc didn't error size=%llu\n", 3 * ps);
+	/*
+	 * At this point we should have enough contiguous space for 2 blocks,
+	 * however they are never buddies (since we freed middle and right) so
+	 * will require the try_harder logic to find them.
+	 */
+	KUNIT_ASSERT_FALSE_MSG(test, drm_buddy_alloc_blocks(&mm, 0, mm_size,
+							   2 * ps, ps, &allocated,
+							   DRM_BUDDY_CONTIGUOUS_ALLOCATION),
+			       "buddy_alloc hit an error size=%d\n", 2 * ps);
+
+	drm_buddy_free_list(&mm, &left);
+	KUNIT_ASSERT_FALSE_MSG(test, drm_buddy_alloc_blocks(&mm, 0, mm_size,
+							   3 * ps, ps, &allocated,
+							   DRM_BUDDY_CONTIGUOUS_ALLOCATION),
+			       "buddy_alloc hit an error size=%d\n", 3 * ps);
+
+	total = 0;
+	list_for_each_entry(block, &allocated, link)
+		total += drm_buddy_block_size(&mm, block);
+
+	KUNIT_ASSERT_EQ(test, total, ps * 2 + ps * 3);
+
+	drm_buddy_free_list(&mm, &allocated);
+	drm_buddy_fini(&mm);
+}
+
 static void drm_test_buddy_alloc_pathological(struct kunit *test)
 {
 	u64 mm_size, size, start = 0;
@@ -280,6 +368,7 @@  static struct kunit_case drm_buddy_tests[] = {
 	KUNIT_CASE(drm_test_buddy_alloc_optimistic),
 	KUNIT_CASE(drm_test_buddy_alloc_pessimistic),
 	KUNIT_CASE(drm_test_buddy_alloc_pathological),
+	KUNIT_CASE(drm_test_buddy_alloc_contiguous),
 	{}
 };