[AMD Official Use Only - General]
Comment inline.
Regards,
Ramesh
-----Original Message-----
From: amd-gfx <amd-gfx-bounces@xxxxxxxxxxxxxxxxxxxxx> On Behalf Of Chen, Xiaogang
Sent: Saturday, January 14, 2023 4:28 AM
To: Kuehling, Felix <Felix.Kuehling@xxxxxxx>; amd-gfx@xxxxxxxxxxxxxxxxxxxxx; dri-devel@xxxxxxxxxxxxxxxxxxxxx
Cc: Koenig, Christian <Christian.Koenig@xxxxxxx>
Subject: Re: [PATCH 6/6] drm/amdgpu: Do bo_va ref counting for KFD BOs
Caution: This message originated from an External Source. Use proper caution when opening attachments, clicking links, or responding.
Reviewed-by: Xiaogang Chen <Xiaoganng.Chen@xxxxxxx>
Regards
Xiaogang
On 1/11/2023 7:31 PM, Felix Kuehling wrote:
> This is needed to correctly handle BOs imported into the GEM API,
> which would otherwise get added twice to the same VM.
>
> Signed-off-by: Felix Kuehling <Felix.Kuehling@xxxxxxx>
> ---
> .../gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c | 28 +++++++++++++++----
> 1 file changed, 22 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
> index df08e84f01d7..8b5ba2e04a79 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
> @@ -370,9 +370,17 @@ static int amdgpu_amdkfd_bo_validate_and_fence(struct amdgpu_bo *bo,
> return ret;
>
> ret = amdgpu_amdkfd_bo_validate(bo, domain, true);
> - if (!ret)
> - dma_resv_add_fence(bo->tbo.base.resv, fence,
> - DMA_RESV_USAGE_BOOKKEEP);
> + if (ret)
> + goto unreserve_out;
> +
> + ret = dma_resv_reserve_fences(bo->tbo.base.resv, 1);
Ramesh: Could this stmt to reserve space for fence be applied in patch 4.
> + if (ret)
> + goto unreserve_out;
> +
> + dma_resv_add_fence(bo->tbo.base.resv, fence,
> + DMA_RESV_USAGE_BOOKKEEP);
> +
> +unreserve_out:
> amdgpu_bo_unreserve(bo);
>
> return ret;
> @@ -785,6 +793,7 @@ static int kfd_mem_attach(struct amdgpu_device *adev, struct kgd_mem *mem,
> uint64_t va = mem->va;
> struct kfd_mem_attachment *attachment[2] = {NULL, NULL};
> struct amdgpu_bo *bo[2] = {NULL, NULL};
> + struct amdgpu_bo_va *bo_va;
> bool same_hive = false;
> int i, ret;
>
> @@ -871,7 +880,12 @@ static int kfd_mem_attach(struct amdgpu_device *adev, struct kgd_mem *mem,
> pr_debug("Unable to reserve BO during memory attach");
> goto unwind;
> }
> - attachment[i]->bo_va = amdgpu_vm_bo_add(adev, vm, bo[i]);
> + bo_va = amdgpu_vm_bo_find(vm, bo[i]);
> + if (!bo_va)
> + bo_va = amdgpu_vm_bo_add(adev, vm, bo[i]);
> + else
> + ++bo_va->ref_count;
> + attachment[i]->bo_va = bo_va;
> amdgpu_bo_unreserve(bo[i]);
> if (unlikely(!attachment[i]->bo_va)) {
> ret = -ENOMEM;
> @@ -895,7 +909,8 @@ static int kfd_mem_attach(struct amdgpu_device *adev, struct kgd_mem *mem,
> continue;
> if (attachment[i]->bo_va) {
> amdgpu_bo_reserve(bo[i], true);
> - amdgpu_vm_bo_del(adev, attachment[i]->bo_va);
> + if (--attachment[i]->bo_va->ref_count == 0)
> + amdgpu_vm_bo_del(adev,
> + attachment[i]->bo_va);
> amdgpu_bo_unreserve(bo[i]);
> list_del(&attachment[i]->list);
> }
> @@ -912,7 +927,8 @@ static void kfd_mem_detach(struct
> kfd_mem_attachment *attachment)
>
> pr_debug("\t remove VA 0x%llx in entry %p\n",
> attachment->va, attachment);
> - amdgpu_vm_bo_del(attachment->adev, attachment->bo_va);
> + if (--attachment->bo_va->ref_count == 0)
> + amdgpu_vm_bo_del(attachment->adev, attachment->bo_va);
> drm_gem_object_put(&bo->tbo.base);
> list_del(&attachment->list);
> kfree(attachment);
