Does this really guarantee VRAM placement? The code doesn't say anything
about that.

Marek


On Fri, May 6, 2022 at 7:23 AM Christian König <
ckoenig.leichtzumerken@gmail.com> wrote:

> Add a AMDGPU_GEM_CREATE_DISCARDABLE flag to note that the content of a BO
> doesn't needs to be preserved during eviction.
>
> KFD was already using a similar functionality for SVM BOs so replace the
> internal flag with the new UAPI.
>
> Only compile tested!
>
> Signed-off-by: Christian König <christian.koenig@amd.com>
> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c    | 4 ++--
>  drivers/gpu/drm/amd/amdgpu/amdgpu_object.c | 1 +
>  drivers/gpu/drm/amd/amdgpu/amdgpu_object.h | 1 -
>  drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c    | 2 +-
>  drivers/gpu/drm/amd/amdkfd/kfd_svm.c       | 2 +-
>  include/uapi/drm/amdgpu_drm.h              | 4 ++++
>  6 files changed, 9 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
> index 2e16484bf606..bf97d8f07f57 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gem.c
> @@ -302,8 +302,8 @@ int amdgpu_gem_create_ioctl(struct drm_device *dev,
> void *data,
>                       AMDGPU_GEM_CREATE_VRAM_CLEARED |
>                       AMDGPU_GEM_CREATE_VM_ALWAYS_VALID |
>                       AMDGPU_GEM_CREATE_EXPLICIT_SYNC |
> -                     AMDGPU_GEM_CREATE_ENCRYPTED))
> -
> +                     AMDGPU_GEM_CREATE_ENCRYPTED |
> +                     AMDGPU_GEM_CREATE_DISCARDABLE))
>                 return -EINVAL;
>
>         /* reject invalid gem domains */
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
> index 8b7ee1142d9a..1944ef37a61e 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
> @@ -567,6 +567,7 @@ int amdgpu_bo_create(struct amdgpu_device *adev,
>                 bp->domain;
>         bo->allowed_domains = bo->preferred_domains;
>         if (bp->type != ttm_bo_type_kernel &&
> +           !(bp->flags & AMDGPU_GEM_CREATE_DISCARDABLE) &&
>             bo->allowed_domains == AMDGPU_GEM_DOMAIN_VRAM)
>                 bo->allowed_domains |= AMDGPU_GEM_DOMAIN_GTT;
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.h
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.h
> index 4c9cbdc66995..147b79c10cbb 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.h
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.h
> @@ -41,7 +41,6 @@
>
>  /* BO flag to indicate a KFD userptr BO */
>  #define AMDGPU_AMDKFD_CREATE_USERPTR_BO        (1ULL << 63)
> -#define AMDGPU_AMDKFD_CREATE_SVM_BO    (1ULL << 62)
>
>  #define to_amdgpu_bo_user(abo) container_of((abo), struct amdgpu_bo_user,
> bo)
>  #define to_amdgpu_bo_vm(abo) container_of((abo), struct amdgpu_bo_vm, bo)
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> index 41d6f604813d..ba3221a25e75 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> @@ -117,7 +117,7 @@ static void amdgpu_evict_flags(struct
> ttm_buffer_object *bo,
>         }
>
>         abo = ttm_to_amdgpu_bo(bo);
> -       if (abo->flags & AMDGPU_AMDKFD_CREATE_SVM_BO) {
> +       if (abo->flags & AMDGPU_GEM_CREATE_DISCARDABLE) {
>                 placement->num_placement = 0;
>                 placement->num_busy_placement = 0;
>                 return;
> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
> b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
> index 5ed8d9b549a4..835b5187f0b8 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
> @@ -531,7 +531,7 @@ svm_range_vram_node_new(struct amdgpu_device *adev,
> struct svm_range *prange,
>         bp.domain = AMDGPU_GEM_DOMAIN_VRAM;
>         bp.flags = AMDGPU_GEM_CREATE_NO_CPU_ACCESS;
>         bp.flags |= clear ? AMDGPU_GEM_CREATE_VRAM_CLEARED : 0;
> -       bp.flags |= AMDGPU_AMDKFD_CREATE_SVM_BO;
> +       bp.flags |= AMDGPU_GEM_CREATE_DISCARDABLE;
>         bp.type = ttm_bo_type_device;
>         bp.resv = NULL;
>
> diff --git a/include/uapi/drm/amdgpu_drm.h b/include/uapi/drm/amdgpu_drm.h
> index 9a1d210d135d..57b9d8f0133a 100644
> --- a/include/uapi/drm/amdgpu_drm.h
> +++ b/include/uapi/drm/amdgpu_drm.h
> @@ -140,6 +140,10 @@ extern "C" {
>   * not require GTT memory accounting
>   */
>  #define AMDGPU_GEM_CREATE_PREEMPTIBLE          (1 << 11)
> +/* Flag that BO can be discarded under memory pressure without keeping the
> + * content.
> + */
> +#define AMDGPU_GEM_CREATE_DISCARDABLE          (1 << 12)
>
>  struct drm_amdgpu_gem_create_in  {
>         /** the requested memory size */
> --
> 2.25.1
>
>