On 2023-10-20 08:33, Christian König wrote:
Looks like the KFD still needs this.
Signed-off-by: Christian König <christian.koenig@xxxxxxx>
Fixes: 8abc1eb2987a ("drm/amdkfd: switch over to using drm_exec v3")
To fix the immediate problem, this patch is Acked-by: Felix Kuehling <Felix.Kuehling@xxxxxxx>As I understand it, this reserves a fence slot for adding an eviction fence. I'm not convinced that this is the right place to do this. Not all callers of reserve_bo_and_vm add eviction fences. In another patch series I added the fence slot reservation in a new helper function amdgpu_amdkfd_bo_validate_and_fence.
Taking another step back, as I understand it, the pre-reservation of fence slots is there to avoid late failures after submitting commands to the HW. This isn't really a problem for KFD because eviction fences aren't directly linked to commands submitted to the HW. It's more like a place holder for future user mode submissions. So I think it's OK to reserve the fence slot just before attaching the fence to a BO resv. We don't have to do the pre-reservation here.
Regards, Felix
--- drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c index 7d6daf8d2bfa..e036011137aa 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c @@ -1103,7 +1103,7 @@ static int reserve_bo_and_vm(struct kgd_mem *mem, if (unlikely(ret)) goto error;- ret = drm_exec_lock_obj(&ctx->exec, &bo->tbo.base);+ ret = drm_exec_prepare_obj(&ctx->exec, &bo->tbo.base, 1); drm_exec_retry_on_contention(&ctx->exec); if (unlikely(ret)) goto error;
