[PATCH v3] drm/amdgpu: Fix VRAM BO swap issue

[Christian König]

Am 26.09.22 um 17:04 schrieb Arunpravin Paneer Selvam:
>
>
> On 9/26/2022 12:01 PM, Christian König wrote:
>> Am 26.09.22 um 07:25 schrieb Arunpravin Paneer Selvam:
>>> DRM buddy manager allocates the contiguous memory requests in
>>> a single block or multiple blocks. So for the ttm move operation
>>> (incase of low vram memory) we should consider all the blocks to
>>> compute the total memory size which compared with the struct
>>> ttm_resource num_pages in order to verify that the blocks are
>>> contiguous for the eviction process.
>>>
>>> v2: Added a Fixes tag
>>> v3: Rewrite the code to save a bit of calculations and
>>>      variables (Christian)
>>>
>>> Fixes: c9cad937c0c5 ("drm/amdgpu: add drm buddy support to amdgpu")
>>> Signed-off-by: Arunpravin Paneer Selvam 
>>> <Arunpravin.PaneerSelvam at amd.com>
>>
>> Reviewed-by: Christian König <christian.koenig at amd.com>
>
> Shall I push this patch into amd-staging-drm-next?

If it applies cleanly then I think so, yes.

Another possibility would be through drm-misc-fixes, but since it is a 
pure amdgpu fix we should try to avoid that.

Christian.

>
> Thanks,
> Arun.
>>
>>> ---
>>>   drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 17 ++++++++++++-----
>>>   1 file changed, 12 insertions(+), 5 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c 
>>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>>> index b1c455329023..dc262d2c2925 100644
>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>>> @@ -424,8 +424,9 @@ static int amdgpu_move_blit(struct 
>>> ttm_buffer_object *bo,
>>>   static bool amdgpu_mem_visible(struct amdgpu_device *adev,
>>>                      struct ttm_resource *mem)
>>>   {
>>> -    uint64_t mem_size = (u64)mem->num_pages << PAGE_SHIFT;
>>> +    u64 mem_size = (u64)mem->num_pages << PAGE_SHIFT;
>>>       struct amdgpu_res_cursor cursor;
>>> +    u64 end;
>>>         if (mem->mem_type == TTM_PL_SYSTEM ||
>>>           mem->mem_type == TTM_PL_TT)
>>> @@ -434,12 +435,18 @@ static bool amdgpu_mem_visible(struct 
>>> amdgpu_device *adev,
>>>           return false;
>>>         amdgpu_res_first(mem, 0, mem_size, &cursor);
>>> +    end = cursor.start + cursor.size;
>>> +    while (cursor.remaining) {
>>> +        amdgpu_res_next(&cursor, cursor.size);
>>>   -    /* ttm_resource_ioremap only supports contiguous memory */
>>> -    if (cursor.size != mem_size)
>>> -        return false;
>>> +        /* ttm_resource_ioremap only supports contiguous memory */
>>> +        if (end != cursor.start)
>>> +            return false;
>>> +
>>> +        end = cursor.start + cursor.size;
>>> +    }
>>>   -    return cursor.start + cursor.size <= 
>>> adev->gmc.visible_vram_size;
>>> +    return end <= adev->gmc.visible_vram_size;
>>>   }
>>>     /*
>>
>