Onnxruntime: Expose DirectML to C#

[jbrownkramer]

Is your feature request related to a problem? Please describe.
I need to be able to run inference on an integrated Intel GPU from C#

System information
Microsoft.ML.OnnxRuntime.DirectML v1.4.0 nuget package.

Describe the solution you'd like
There seems to be no ability to select the DirectML provider from the C# api, even when using the DirectML build. I would like that to be exposed.

Describe alternatives you've considered
I have considered using the OpenVINO provider, which apparently recently added C# support. However, there is no nuget package, and I have not yet been able to make it through the installation and build process to see if that works.

[dashesy]

issue #4876 related

[hariharans29]

issue #4876 related

@dashesy - Not sure if these are completely related. The issue here is that there is a Nuget supported for DML (Microsoft.ML.OnnxRuntime.DirectML) and the C# API lacks support for creating sessions that can leverage the binary shipped in the Nuget. #4876 seems to be a request for a Nuget for each EP supported in ORT.

[Alvaromah]

Trying to use the DML provider in C# with options.AppendExecutionProvider_Dml() gives the following error:
System.EntryPointNotFoundException: Unable to find an entry point named 'OrtSessionOptionsAppendExecutionProvider_Dml' in DLL 'onnxruntime'.
What am I missing?

[hariharans29]

You need to build onnxruntime with dml enabled (—use_dml). Please refer to the steps in Build.md.

[Alvaromah]

@hariharans29 - Thanks for your quick response but I did build onnxruntime with --use_dml option but still having the same error.
Steps taken:

1. build.bat --use_dml
2. Open and build /onnxruntime/csharp/OnnxRuntime.CSharp.sln
3. Open and execute sample Microsoft.ML.OnnxRuntime.InferenceSample with AppendExecutionProvider_Dml() option
4. System.EntryPointNotFoundException

[Alvaromah]

After some research, it seems to be a problem with the name of the exported function.
The name of the function exported by the onnxruntime.dll is OrtSessionOptionsAppendExecutionProvider_DML() but the CSharp code uses:
OrtSessionOptionsAppendExecutionProvider_dml (dml in lower case).

After fixing the typo, I get the following error:
Exception(1) tid(4990) 80004005 Unspecified error
[onnxruntime::CreateExecutionProviderFactory_DML(D3D12CreateDevice(adapter.Get(), D3D_FEATURE_LEVEL_11_0, IID_PPV_ARGS(&d3d12_device)))]

[hariharans29]

Oops you're right, thank you. I ll fix the typo.

@fdwr - Any idea why the DML EP doesn't get initialized properly ?

[Alvaromah]

Its working now. It was probably a problem with my device adapter. Thanks!

[hariharans29]

Great thanks. Did you pass in a device id of 0 ?

[hariharans29]

Actually - I get the same exception when I try on my machine. Did you try anything to solve the problem with the device adapter ?

[Alvaromah]

I'm currently using the onnxruntime.dll from package Microsoft.ML.OnnxRuntime.DirectML and it works for me.
I'm passing device id 0.

[HydeNaut]

I've tried using the Microsoft.ML.OnnxRuntime.DirectML 1.4.0 Nuget and I don't see the DML option available. Should it be be there at the moment or would it be in the next update?

[hariharans29]

It was added after 1.4.0 released. So it should be in the upcoming release or you can build from source following the step listed in the discussion above.