[PATCH] drm/mm: add ig_frag selftest

[Nirmoy]

On 5/28/20 8:49 PM, Christian König wrote:
> Am 28.05.20 um 15:05 schrieb Nirmoy Das:
>> This patch introduces fragmentation in the address range
>> and measures time taken by 10k insertions for each modes.
>>
>> ig_frag() will fail if one of the mode takes more than 1 sec.
>>
>> Output:
>> <snip>
>> [   37.326723] drm_mm: igt_sanitycheck - ok!
>> [   37.326727] igt_debug 0x0000000000000000-0x0000000000000200: 512: 
>> free
>> [   37.326728] igt_debug 0x0000000000000200-0x0000000000000600: 1024: 
>> used
>> [   37.326728] igt_debug 0x0000000000000600-0x0000000000000a00: 1024: 
>> free
>> [   37.326729] igt_debug 0x0000000000000a00-0x0000000000000e00: 1024: 
>> used
>> [   37.326730] igt_debug 0x0000000000000e00-0x0000000000001000: 512: 
>> free
>> [   37.326730] igt_debug total: 4096, used 2048 free 2048
>> [   56.040064] drm_mm: best fragmented insert took 504 msecs
>> [   56.082184] drm_mm: bottom-up fragmented insert took 40 msecs
>> [   56.102255] drm_mm: top-down fragmented insert took 20 msecs
>> [   56.107177] drm_mm: evict fragmented insert took 4 msecs
>> <snip>
>>
>> Signed-off-by: Nirmoy Das <nirmoy.das at amd.com>
>
> Off hand that looks like it should work, but I'm really not an expert 
> for the drm_mm code.
>
> Feel free to add an Acked-by: Christian König 
> <christian.koenig at amd.com>, but I would consider doing what Chris said 
> as well.


Thanks Christian,. Yes I will send a v2 with Chris's suggestions.


Nirmoy

>
> Christian.
>
>> ---
>>   drivers/gpu/drm/selftests/drm_mm_selftests.h |  1 +
>>   drivers/gpu/drm/selftests/test-drm_mm.c      | 59 ++++++++++++++++++++
>>   2 files changed, 60 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/selftests/drm_mm_selftests.h 
>> b/drivers/gpu/drm/selftests/drm_mm_selftests.h
>> index 6b943ea1c57d..8c87c964176b 100644
>> --- a/drivers/gpu/drm/selftests/drm_mm_selftests.h
>> +++ b/drivers/gpu/drm/selftests/drm_mm_selftests.h
>> @@ -14,6 +14,7 @@ selftest(insert, igt_insert)
>>   selftest(replace, igt_replace)
>>   selftest(insert_range, igt_insert_range)
>>   selftest(align, igt_align)
>> +selftest(frag, igt_frag)
>>   selftest(align32, igt_align32)
>>   selftest(align64, igt_align64)
>>   selftest(evict, igt_evict)
>> diff --git a/drivers/gpu/drm/selftests/test-drm_mm.c 
>> b/drivers/gpu/drm/selftests/test-drm_mm.c
>> index 9aabe82dcd3a..4c08ca86bb86 100644
>> --- a/drivers/gpu/drm/selftests/test-drm_mm.c
>> +++ b/drivers/gpu/drm/selftests/test-drm_mm.c
>> @@ -1033,6 +1033,65 @@ static int igt_insert_range(void *ignored)
>>       return 0;
>>   }
>>   +static int igt_frag(void *ignored)
>> +{
>> +    const struct insert_mode *mode;
>> +    struct drm_mm mm;
>> +    struct drm_mm_node *nodes, *node, *next;
>> +    unsigned int size = 4096, align = 8192;
>> +    unsigned long start, timeout = 1000;
>> +    const unsigned int max_count = 10000;
>> +    unsigned int i;
>> +    int ret = -EINVAL;
>> +
>> +    /* For each of the possible insertion modes, we pass an size, 
>> alignment
>> +     * value that is known to introduce fragmentation and check that it
>> +     * doesn't take more than 1 sec.
>> +     */
>> +
>> +    nodes = vzalloc(array_size(max_count, sizeof(*nodes)));
>> +    if (!nodes)
>> +        goto err;
>> +
>> +    drm_mm_init(&mm, 1, U64_MAX - 2);
>> +
>> +    for (mode = insert_modes; mode->name; mode++) {
>> +        start = jiffies;
>> +
>> +        for (i = 0; i < max_count; i++) {
>> +            if (jiffies_to_msecs(jiffies - start) >= timeout) {
>> +                pr_err("%s fragmented insert took more than %lu 
>> msecs\n",
>> +                       mode->name, timeout);
>> +                goto out;
>> +            }
>> +
>> +            if (!expect_insert(&mm, &nodes[i],
>> +                       size, align, i, mode)) {
>> +                pr_err("%s insert failed with alignment=%d",
>> +                       mode->name, align);
>> +                goto out;
>> +            }
>> +        }
>> +
>> +        pr_info("%s fragmented insert took %d msecs\n",
>> +            mode->name, jiffies_to_msecs(jiffies - start));
>> +        drm_mm_for_each_node_safe(node, next, &mm)
>> +            drm_mm_remove_node(node);
>> +        DRM_MM_BUG_ON(!drm_mm_clean(&mm));
>> +
>> +        cond_resched();
>> +    }
>> +
>> +    ret = 0;
>> +out:
>> +    drm_mm_for_each_node_safe(node, next, &mm)
>> +        drm_mm_remove_node(node);
>> +    drm_mm_takedown(&mm);
>> +    vfree(nodes);
>> +err:
>> +    return ret;
>> +}
>> +
>>   static int igt_align(void *ignored)
>>   {
>>       const struct insert_mode *mode;
>