On 16.09.25 13:58, Pierre-Eric Pelloux-Prayer wrote:
>
>
> Le 16/09/2025 à 12:52, Christian König a écrit :
>> On 16.09.25 11:46, Pierre-Eric Pelloux-Prayer wrote:
>>>
>>>
>>> Le 16/09/2025 à 11:25, Christian König a écrit :
>>>> On 16.09.25 09:08, Pierre-Eric Pelloux-Prayer wrote:
>>>>> amdgpu_ttm_copy_mem_to_mem has a single caller, make sure the out
>>>>> fence is non-NULL to simplify the code.
>>>>> Since none of the pointers should be NULL, we can enable
>>>>> __attribute__((nonnull))__.
>>>>>
>>>>> While at it make the function static since it's only used from
>>>>> amdgpuu_ttm.c.
>>>>>
>>>>> Signed-off-by: Pierre-Eric Pelloux-Prayer
>>>>> <pierre-eric.pelloux-pra...@amd.com>
>>>>> ---
>>>>> drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 17 ++++++++---------
>>>>> drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h | 6 ------
>>>>> 2 files changed, 8 insertions(+), 15 deletions(-)
>>>>>
>>>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>>>>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>>>>> index 27ab4e754b2a..70b817b5578d 100644
>>>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>>>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>>>>> @@ -284,12 +284,13 @@ static int amdgpu_ttm_map_buffer(struct
>>>>> ttm_buffer_object *bo,
>>>>> * move and different for a BO to BO copy.
>>>>> *
>>>>> */
>>>>> -int amdgpu_ttm_copy_mem_to_mem(struct amdgpu_device *adev,
>>>>> - const struct amdgpu_copy_mem *src,
>>>>> - const struct amdgpu_copy_mem *dst,
>>>>> - uint64_t size, bool tmz,
>>>>> - struct dma_resv *resv,
>>>>> - struct dma_fence **f)
>>>>> +__attribute__((nonnull))
>>>>
>>>> That looks fishy.
>>>>
>>>>> +static int amdgpu_ttm_copy_mem_to_mem(struct amdgpu_device *adev,
>>>>> + const struct amdgpu_copy_mem *src,
>>>>> + const struct amdgpu_copy_mem *dst,
>>>>> + uint64_t size, bool tmz,
>>>>> + struct dma_resv *resv,
>>>>> + struct dma_fence **f)
>>>>
>>>> I'm not an expert for those, but looking at other examples that should be
>>>> here and look something like:
>>>>
>>>> __attribute__((nonnull(7)))
>>>
>>> Both syntax are valid. The GCC docs says:
>>>
>>> If no arg-index is given to the nonnull attribute, all pointer
>>> arguments are marked as non-null
>>
>> Never seen that before. Is that gcc specifc or standardized?
>
> clang supports it:
>
> https://clang.llvm.org/docs/AttributeReference.html#id10
>
> And both syntaxes are already used in the drm subtree by i915.
Ok in that case Reviewed-by: Christian König <christian.koe...@amd.com>.
Regards,
Christian.
>
> Pierre-Eric
>
>>
>>>
>>>
>>>>
>>>> But I think for this case here it is also not a must have to have that.
>>>
>>> I can remove it if you prefer, but it doesn't hurt to have the compiler
>>> validate usage of the functions.
>>
>> Yeah it's clearly useful, but I'm worried that clang won't like it.
>>
>> Christian.
>>
>>>
>>> Pierre-Eric
>>>
>>>
>>>>
>>>> Regards,
>>>> Christian.
>>>>
>>>>> {
>>>>> struct amdgpu_ring *ring = adev->mman.buffer_funcs_ring;
>>>>> struct amdgpu_res_cursor src_mm, dst_mm;
>>>>> @@ -363,9 +364,7 @@ int amdgpu_ttm_copy_mem_to_mem(struct amdgpu_device
>>>>> *adev,
>>>>> }
>>>>> error:
>>>>> mutex_unlock(&adev->mman.gtt_window_lock);
>>>>> - if (f)
>>>>> - *f = dma_fence_get(fence);
>>>>> - dma_fence_put(fence);
>>>>> + *f = fence;
>>>>> return r;
>>>>> }
>>>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h
>>>>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h
>>>>> index bb17987f0447..07ae2853c77c 100644
>>>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h
>>>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h
>>>>> @@ -170,12 +170,6 @@ int amdgpu_copy_buffer(struct amdgpu_ring *ring,
>>>>> uint64_t src_offset,
>>>>> struct dma_resv *resv,
>>>>> struct dma_fence **fence, bool direct_submit,
>>>>> bool vm_needs_flush, uint32_t copy_flags);
>>>>> -int amdgpu_ttm_copy_mem_to_mem(struct amdgpu_device *adev,
>>>>> - const struct amdgpu_copy_mem *src,
>>>>> - const struct amdgpu_copy_mem *dst,
>>>>> - uint64_t size, bool tmz,
>>>>> - struct dma_resv *resv,
>>>>> - struct dma_fence **f);
>>>>> int amdgpu_ttm_clear_buffer(struct amdgpu_bo *bo,
>>>>> struct dma_resv *resv,
>>>>> struct dma_fence **fence);
>>
