Enhance PartitionGraph (apache#14277)

* Enhance PartitionGraph

* Fix lint

* Fix test

* Run CI

* Change subgraph property register

* Change doc

* Fix name

* Run CI

* Add env var in doc

* Address comments.

* run CI

docs/tutorials/c++/subgraphAPI.md

@@ -97,23 +97,57 @@ class SgProperty : public SubgraphProperty {
     return n;
   }
   SubgraphSelectorPtr CreateSubgraphSelector() const override {
-    return std::make_shared<SgSelector>();
+    auto property = std::make_shared<CreateSubgraphSelector>();
+    property->SetAttr<std::string>("property_name", "subgraph example pass"); // Optional, better to have it.
+    property->SetAttr<bool>("inference_only", true); // Optional, only for inference_only pass.
+    return property;
   }
 };
 ```
+`SetAttr` is optional and developer can define their own attributes to control property behavior.
+There're 2 built-in attributes that used by MXNet executor.
 
-After defining the subgraph property, we need to register it.
+`property_name`  : std::string, name of this property.
+
+`inference_only` : bool, apply this property only for inference. Property will be skiped when need_grad=True. Default `false` if this attribute isn't defined.
+
+After defining the subgraph property, we need to register it in .cc file.
 
 ```C++
 MXNET_REGISTER_SUBGRAPH_PROPERTY(SgTest, SgProperty);
 ```
 
-After compiling this subgraph mechanism into MXNet, we can use the environment variable `MXNET_SUBGRAPH_BACKEND` to activate it.
+It's possible to register multiple properties for same backend. In practice, we recommend to put each property definition into .h file, and register backend in single .cc file. Property will be executed according to the register order.
+
+```C++
+#include "SgProperty.h" // Define SgProperty class
+#include "SgProperty2.h" // Define SgProperty2 class
+#include "SgProperty3.h" // Define SgProperty3 class
+
+MXNET_REGISTER_SUBGRAPH_PROPERTY(SgTest, SgProperty);  // Execution order 1.
+MXNET_REGISTER_SUBGRAPH_PROPERTY(SgTest, SgProperty2); // Execution order 2.
+MXNET_REGISTER_SUBGRAPH_PROPERTY(SgTest, SgProperty3); // Execution order 3.
+```
+
+After compiling this subgraph mechanism into MXNet, we can use the environment variable `MXNET_SUBGRAPH_BACKEND` to activate it during symbol bind.
 
 ```bash
 export MXNET_SUBGRAPH_BACKEND=SgTest
 ```
 
+Or you can use python symbol API `get_backend_symbol` to run all properties registered for this backend and get returned symbol.
+
+```Python
+sym, arg_params, aux_params = mx.model.load_checkpoint(prefix, epoch)
+sym = sym.get_backend_symbol('SgTest')
+```
+
+When `SgProperty` is activated, a message will be shown in terminal as
+
+```bash
+start to execute subgraph example pass.
+```
+
 This tutorial shows a simple example of how to use the subgraph API to search for patterns in an NNVM graph.
 Intested users can try different pattern matching rules (i.e., define their own `SubgraphSelector`) and
 attach different operators to execute the subgraphs.

docs/tutorials/mkldnn/MKLDNN_README.md

@@ -306,6 +306,14 @@ Graph optimization by subgraph feature are available in master branch. You can b
 ```
 export MXNET_SUBGRAPH_BACKEND=MKLDNN
 ```
+
+When `MKLDNN` backend is enabled, advanced control options are avaliable:
+
+```
+export MXNET_DISABLE_MKLDNN_CONV_OPT=1 # disable MKLDNN convolution optimization pass
+export MXNET_DISABLE_MKLDNN_FC_OPT=1 # disable MKLDNN FullyConnected optimization pass
+```
+
 
 This limitations of this experimental feature are:
 

example/quantization/imagenet_gen_qsym_mkldnn.py

@@ -180,7 +180,6 @@ def save_params(fname, arg_params, aux_params, logger=None):
         sym, arg_params, aux_params = mx.model.load_checkpoint(prefix, epoch)
 
     sym = sym.get_backend_symbol('MKLDNN')
-    sym = sym.get_backend_symbol('MKLDNN_FC')
 
     # get batch size
     batch_size = args.batch_size
@@ -303,7 +302,6 @@ def save_params(fname, arg_params, aux_params, logger=None):
                              % calib_mode)
         sym_name = '%s-symbol.json' % (prefix + suffix)
     qsym = qsym.get_backend_symbol('MKLDNN_POST_QUANTIZE')
-    qsym = qsym.get_backend_symbol('MKLDNN_POST_FC_QUANTIZE')
     save_symbol(sym_name, qsym, logger)
     param_name = '%s-%04d.params' % (prefix + '-quantized', epoch)
     save_params(param_name, qarg_params, aux_params, logger)

src/c_api/c_api_symbolic.cc

@@ -722,14 +722,15 @@ int MXGenBackendSubgraph(SymbolHandle sym_handle, const char *backend,
   API_BEGIN();
   nnvm::Symbol *sym = static_cast<nnvm::Symbol *>(sym_handle);
   *s = sym->Copy();
-  nnvm::Graph g = Symbol2Graph(*s);
-  mxnet::op::SubgraphPropertyPtr property =
-      mxnet::op::SubgraphPropertyRegistry::Get()->CreateSubgraphProperty(
-          backend);
-  g.attrs["subgraph_property"] =
-      std::make_shared<nnvm::any>(std::move(property));
-  g = ApplyPass(std::move(g), "PartitionGraph");
-  s->outputs = g.outputs;
+  std::vector<mxnet::op::SubgraphPropertyPtr> properties =
+      mxnet::op::SubgraphPropertyRegistry::Get()->CreateSubgraphProperty(backend);
+  for (auto property : properties) {
+    nnvm::Graph g = Symbol2Graph(*s);
+    property->SetAttr("graph", g);
+    g.attrs["subgraph_property"] = std::make_shared<nnvm::any>(std::move(property));
+    g = nnvm::ApplyPass(std::move(g), "PartitionGraph");
+    s->outputs = g.outputs;
+  }
   *ret_sym_handle = s;
   API_END_HANDLE_ERROR(delete s);
 }

src/c_api/c_api_test.cc

@@ -40,16 +40,19 @@ int MXPartitionGraphByOpNames(SymbolHandle sym_handle,
   }
   nnvm::Symbol* sym = static_cast<nnvm::Symbol*>(sym_handle);
   *s = sym->Copy();
-  nnvm::Graph g;
-  g.outputs = s->outputs;
   if (!op_name_set.empty()) {
-    mxnet::op::SubgraphPropertyPtr property
-        = mxnet::op::SubgraphPropertyRegistry::Get()->CreateSubgraphProperty(prop_name);
-    property->SetAttr("op_names", op_name_set);
-    g.attrs["subgraph_property"] = std::make_shared<nnvm::any>(std::move(property));
+    std::vector<mxnet::op::SubgraphPropertyPtr> properties =
+        mxnet::op::SubgraphPropertyRegistry::Get()->CreateSubgraphProperty(prop_name);
+    for (auto property : properties) {
+      nnvm::Graph g;
+      g.outputs = s->outputs;
+      property->SetAttr("graph", g);
+      property->SetAttr("op_names", op_name_set);
+      g.attrs["subgraph_property"] = std::make_shared<nnvm::any>(std::move(property));
+      g = nnvm::ApplyPass(std::move(g), "PartitionGraph");
+      s->outputs = g.outputs;
+    }
   }
-  g = nnvm::ApplyPass(std::move(g), "PartitionGraph");
-  s->outputs = g.outputs;
   *ret_sym_handle = s;
   API_END_HANDLE_ERROR(delete s);
 }