Cannot add cpu extension: libMKLDNNPlugin.so in Python ?

[song__minghui]

When I ran following python program:

# this folder include all extensions (.so), including: libcpu_extension_avx2.so, libMKLDNNPlugin.so and some others
plugin_dir = '/home/temp/intel/openvino/deployment_tools/inference_engine/lib/intel64'

plugin = IEPlugin(device=‘CPU', plugin_dirs=plugin_dir)

cpu_extension_path = '/home/temp/intel/openvino/deployment_tools/inference_engine/lib/intel64/libMKLDNNPlugin.so'

plugin.add_cpu_extension(cpu_extension_path)

An error happens:

RuntimeError: dlSym cannot locate method 'CreateExtension': /home/temp/intel/openvino/deployment_tools/inference_engine/lib/intel64/libMKLDNNPlugin.so: undefined symbol: CreateExtension

looks like the function CreateExtension is not included in libMKLDNNPlugin.so.  When I use libcpu_extension_avx2.so, no errors happend, and this function (CreateExtension) is exactly contained in libcpu_extension_avx2.so.

Any advise ? thanks in advance

[Shubha_R_Intel]

Dear song, minghui,

Looks like you solved your own problem. 

When I use libcpu_extension_avx2.so, no errors happend, and this function (CreateExtension) is exactly contained in libcpu_extension_avx2.so.

CPU extensions are in fact handled in a separate library as you've discovered. They are not part of MKLDNNPlugin.so.

Thanks,

Shubha

[verma__Ashish]

I am using latest OpenVino release 2020.2 in Linux .

I have separated out the code of face detector from interactive_face_detection_demo but when I am running the code,

I am getting this error-

terminate called after throwing an instance of 'InferenceEngine::details::InferenceEngineException'
  what():  dlSym cannot locate method 'CreateExtension': /opt/intel/openvino/deployment_tools/inference_engine/lib/intel64/libMKLDNNPlugin.so: undefined symbol: CreateExtension

while  adding the CPU extension

if ((deviceName.find("CPU") != std::string::npos))

{ // CPU(MKLDNN) extensions are loaded as a shared library and passed as a pointer to base extension

auto extension_ptr = make_so_pointer<IExtension>("/opt/intel/openvino/deployment_tools/inference_engine/lib/intel64/libMKLDNNPlugin.so");

// auto extension_ptr = make_so_pointer<IExtension>("/opt/intel/openvino/deployment_tools/inference_engine/lib/intel64/libcpu_extension_avx2.so"); ie.AddExtension(extension_ptr, "CPU");

// slog::info << "CPU Extension loaded: " << FLAGS_l << slog::endl;

}

libcpu_extension_avx2.so is not available in the latest release.

Can you tell me what I am doing wrong?

Regards

Ashish

[JAIVIN_J_Intel]

Hi Ashish,

CPU extensions are moved to plugin since OpenVINO release 2020.1. The extensions are loaded automatically while loading the CPU plugin, hence 'AddExtension' need not be used.

Regards,

Jaivin