Re: [PATCH v2 3/4] drm/amdkfd: Move gfx9 MQD to VRAM domain

["Kuehling, Felix" <felix.kuehling@amd.com>]

On 2025-12-01 09:28, Philip Yang wrote:
> To reduce queue switch latency further, move MQD to VRAM domain, add
> AMDGPU_GEM_CREATE_VRAM_CONTIGUOUS flag to allocate contiguous pages
> using one buddy block.

Why does it need to be contiguous? In the next patch you're mapping it 
in the GART anyway.

Regards,
   Felix


>
> Signed-off-by: Philip Yang <Philip.Yang@amd.com>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.c      | 3 ++-
>   drivers/gpu/drm/amd/amdkfd/kfd_mqd_manager_v9.c | 2 +-
>   2 files changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.c
> index 9cd1660b8f60..c11e37915365 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.c
> @@ -329,7 +329,8 @@ int amdgpu_amdkfd_alloc_gtt_mem(struct amdgpu_device *adev, size_t size,
>   	bp.size = size;
>   	bp.byte_align = PAGE_SIZE;
>   	bp.domain = domain;
> -	bp.flags = AMDGPU_GEM_CREATE_CPU_GTT_USWC;
> +	bp.flags = AMDGPU_GEM_CREATE_VRAM_CONTIGUOUS |
> +		   AMDGPU_GEM_CREATE_CPU_GTT_USWC;
>   	bp.type = ttm_bo_type_kernel;
>   	bp.resv = NULL;
>   	bp.bo_ptr_size = sizeof(struct amdgpu_bo);
> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_mqd_manager_v9.c b/drivers/gpu/drm/amd/amdkfd/kfd_mqd_manager_v9.c
> index a489d43d5f64..c6945c842267 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_mqd_manager_v9.c
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_mqd_manager_v9.c
> @@ -139,7 +139,7 @@ static struct kfd_mem_obj *allocate_mqd(struct kfd_node *node,
>   			(ALIGN(q->ctl_stack_size, PAGE_SIZE) +
>   			ALIGN(sizeof(struct v9_mqd), PAGE_SIZE)) *
>   			NUM_XCC(node->xcc_mask),
> -			AMDGPU_GEM_DOMAIN_GTT,
> +			AMDGPU_GEM_DOMAIN_VRAM,
>   			&(mqd_mem_obj->gtt_mem),
>   			&(mqd_mem_obj->gpu_addr),
>   			(void *)&(mqd_mem_obj->cpu_ptr), true);