[PATCH v2] drm/amdgpu: refine amdgpu_bo_create_kernel_at()

Christian König christian.koenig at amd.com
Fri Jul 28 08:00:50 UTC 2023


Am 28.07.23 um 09:00 schrieb Lazar, Lijo:
>
>
> On 7/28/2023 11:34 AM, Lang Yu wrote:
>> Use amdgpu_bo_create_reserved() to create a BO in VRAM
>> domain would fail if requested VRAM size is large(>128MB)
>> on APU which usually has a default 512MB VRAM.
>>
>> That's because VRAM is framgented after several allocations.
>>
>> The approach is using amdgpu_bo_create_reserved() to
>> create a BO in CPU domain first, it will always succeed.
>>
>> v2: Don't overwrite the contents at specific offset.
>>
>> Signed-off-by: Lang Yu <Lang.Yu at amd.com>
>> ---
>>   drivers/gpu/drm/amd/amdgpu/amdgpu_object.c | 24 ++++++++++++++++------
>>   drivers/gpu/drm/amd/amdgpu/amdgpu_object.h |  3 ++-
>>   drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c    | 15 +++++++-------
>>   drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c   |  2 +-
>>   4 files changed, 28 insertions(+), 16 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c 
>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
>> index ff73cc11d47e..fa30e96f27d0 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
>> @@ -358,6 +358,7 @@ int amdgpu_bo_create_kernel(struct amdgpu_device 
>> *adev,
>>    * @offset: offset of the BO
>>    * @size: size of the BO
>>    * @bo_ptr:  used to initialize BOs in structures
>> + * @gpu_addr: GPU addr of the pinned BO
>>    * @cpu_addr: optional CPU address mapping
>>    *
>>    * Creates a kernel BO at a specific offset in VRAM.
>> @@ -367,7 +368,8 @@ int amdgpu_bo_create_kernel(struct amdgpu_device 
>> *adev,
>>    */
>>   int amdgpu_bo_create_kernel_at(struct amdgpu_device *adev,
>>                      uint64_t offset, uint64_t size,
>> -                   struct amdgpu_bo **bo_ptr, void **cpu_addr)
>> +                   struct amdgpu_bo **bo_ptr,
>> +                   u64 *gpu_addr, void **cpu_addr)
>
> A generic question (not considering other details in this patch) - 
> this API is literally asking to create BO at a particular GPU VRAM 
> offset. The offset goes in as the input, so why does it need to return 
> a GPU offset?

Yeah, that's exactly why I said that the intention of the function was 
misunderstood.

This change here doesn't seem to make much sense.

Regards,
Christian.

>
> Thanks,
> Lijo
>
>>   {
>>       struct ttm_operation_ctx ctx = { false, false };
>>       unsigned int i;
>> @@ -377,32 +379,42 @@ int amdgpu_bo_create_kernel_at(struct 
>> amdgpu_device *adev,
>>       size = ALIGN(size, PAGE_SIZE);
>>         r = amdgpu_bo_create_reserved(adev, size, PAGE_SIZE,
>> -                      AMDGPU_GEM_DOMAIN_VRAM, bo_ptr, NULL,
>> -                      cpu_addr);
>> +                      AMDGPU_GEM_DOMAIN_CPU,
>> +                      bo_ptr, NULL, NULL);
>>       if (r)
>>           return r;
>>         if ((*bo_ptr) == NULL)
>>           return 0;
>>   +    (*bo_ptr)->flags = AMDGPU_GEM_CREATE_VRAM_CONTIGUOUS;
>> +    (*bo_ptr)->flags |= cpu_addr ? 
>> AMDGPU_GEM_CREATE_CPU_ACCESS_REQUIRED
>> +        : AMDGPU_GEM_CREATE_NO_CPU_ACCESS;
>> +
>>       /*
>>        * Remove the original mem node and create a new one at the 
>> request
>>        * position.
>>        */
>> -    if (cpu_addr)
>> -        amdgpu_bo_kunmap(*bo_ptr);
>> -
>>       ttm_resource_free(&(*bo_ptr)->tbo, &(*bo_ptr)->tbo.resource);
>>         for (i = 0; i < (*bo_ptr)->placement.num_placement; ++i) {
>>           (*bo_ptr)->placements[i].fpfn = offset >> PAGE_SHIFT;
>>           (*bo_ptr)->placements[i].lpfn = (offset + size) >> PAGE_SHIFT;
>> +        (*bo_ptr)->placements[i].mem_type = TTM_PL_VRAM;
>> +        (*bo_ptr)->placements[i].flags = TTM_PL_FLAG_CONTIGUOUS;
>> +
>> +        if (!((*bo_ptr)->flags & 
>> AMDGPU_GEM_CREATE_CPU_ACCESS_REQUIRED))
>> +            (*bo_ptr)->placements[i].flags |= TTM_PL_FLAG_TOPDOWN;
>>       }
>> +
>>       r = ttm_bo_mem_space(&(*bo_ptr)->tbo, &(*bo_ptr)->placement,
>>                    &(*bo_ptr)->tbo.resource, &ctx);
>>       if (r)
>>           goto error;
>>   +    if (gpu_addr)
>> +        *gpu_addr = amdgpu_bo_gpu_offset(*bo_ptr);
>> +
>>       if (cpu_addr) {
>>           r = amdgpu_bo_kmap(*bo_ptr, cpu_addr);
>>           if (r)
>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.h 
>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.h
>> index 5d3440d719e4..8f5b5664a1b6 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.h
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.h
>> @@ -315,7 +315,8 @@ int amdgpu_bo_create_kernel(struct amdgpu_device 
>> *adev,
>>                   u64 *gpu_addr, void **cpu_addr);
>>   int amdgpu_bo_create_kernel_at(struct amdgpu_device *adev,
>>                      uint64_t offset, uint64_t size,
>> -                   struct amdgpu_bo **bo_ptr, void **cpu_addr);
>> +                   struct amdgpu_bo **bo_ptr,
>> +                   u64 *gpu_addr, void **cpu_addr);
>>   int amdgpu_bo_create_user(struct amdgpu_device *adev,
>>                 struct amdgpu_bo_param *bp,
>>                 struct amdgpu_bo_user **ubo_ptr);
>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c 
>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>> index 7c6dd3de1867..a210c243dac0 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>> @@ -1619,7 +1619,7 @@ static int 
>> amdgpu_ttm_fw_reserve_vram_init(struct amdgpu_device *adev)
>> adev->mman.fw_vram_usage_start_offset,
>>                         adev->mman.fw_vram_usage_size,
>> &adev->mman.fw_vram_usage_reserved_bo,
>> -                      &adev->mman.fw_vram_usage_va);
>> +                      NULL, &adev->mman.fw_vram_usage_va);
>>   }
>>     /**
>> @@ -1644,7 +1644,7 @@ static int 
>> amdgpu_ttm_drv_reserve_vram_init(struct amdgpu_device *adev)
>> adev->mman.drv_vram_usage_start_offset,
>>                         adev->mman.drv_vram_usage_size,
>> &adev->mman.drv_vram_usage_reserved_bo,
>> -                      &adev->mman.drv_vram_usage_va);
>> +                      NULL, &adev->mman.drv_vram_usage_va);
>>   }
>>     /*
>> @@ -1729,8 +1729,7 @@ static int amdgpu_ttm_reserve_tmr(struct 
>> amdgpu_device *adev)
>>           ret = amdgpu_bo_create_kernel_at(adev,
>>                            ctx->c2p_train_data_offset,
>>                            ctx->train_data_size,
>> -                         &ctx->c2p_bo,
>> -                         NULL);
>> +                         &ctx->c2p_bo, NULL, NULL);
>>           if (ret) {
>>               DRM_ERROR("alloc c2p_bo failed(%d)!\n", ret);
>>               amdgpu_ttm_training_reserve_vram_fini(adev);
>> @@ -1742,7 +1741,7 @@ static int amdgpu_ttm_reserve_tmr(struct 
>> amdgpu_device *adev)
>>       if (!adev->gmc.is_app_apu) {
>>           ret = amdgpu_bo_create_kernel_at(
>>               adev, adev->gmc.real_vram_size - reserve_size,
>> -            reserve_size, &adev->mman.fw_reserved_memory, NULL);
>> +            reserve_size, &adev->mman.fw_reserved_memory, NULL, NULL);
>>           if (ret) {
>>               DRM_ERROR("alloc tmr failed(%d)!\n", ret);
>> amdgpu_bo_free_kernel(&adev->mman.fw_reserved_memory,
>> @@ -1885,14 +1884,14 @@ int amdgpu_ttm_init(struct amdgpu_device *adev)
>>           r = amdgpu_bo_create_kernel_at(adev, 0,
>>                              adev->mman.stolen_vga_size,
>> &adev->mman.stolen_vga_memory,
>> -                           NULL);
>> +                           NULL, NULL);
>>           if (r)
>>               return r;
>>             r = amdgpu_bo_create_kernel_at(adev, 
>> adev->mman.stolen_vga_size,
>>                              adev->mman.stolen_extended_size,
>> &adev->mman.stolen_extended_memory,
>> -                           NULL);
>> +                           NULL, NULL);
>>             if (r)
>>               return r;
>> @@ -1901,7 +1900,7 @@ int amdgpu_ttm_init(struct amdgpu_device *adev)
>> adev->mman.stolen_reserved_offset,
>>                              adev->mman.stolen_reserved_size,
>> &adev->mman.stolen_reserved_memory,
>> -                           NULL);
>> +                           NULL, NULL);
>>           if (r)
>>               return r;
>>       } else {
>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c 
>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
>> index 41aa853a07d2..b93b42b916ce 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_virt.c
>> @@ -397,7 +397,7 @@ static void amdgpu_virt_ras_reserve_bps(struct 
>> amdgpu_device *adev)
>>            */
>>           if (amdgpu_bo_create_kernel_at(adev, bp << 
>> AMDGPU_GPU_PAGE_SHIFT,
>>                              AMDGPU_GPU_PAGE_SIZE,
>> -                           &bo, NULL))
>> +                           &bo, NULL, NULL))
>>               DRM_DEBUG("RAS WARN: reserve vram for retired page %llx 
>> fail\n", bp);
>>             data->bps_bo[i] = bo;



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