NNAPI HAL: Change IEvent to explicit callbacks

IEvent was a synchronization primitive which caused some confusion
in the interface. Originally the event object was paired with an
asynchronous task, and the asynchronous task would signal this event
when the corresponding output was ready to be used.

In the case of IDevice::prepareModel, the function call would return an
IPreparedModel object that was not guaranteed to be prepared until the
runtime had returned from waiting on the corresponding event object.
The event object has been changed to two explicit callbacks--
IPreparedModelCallback and IExecutionCallback. Now,
IDevice::prepareModel no longer returns an unfinished IPreparedModel;
instead, it will pass the IPreparedModel object to the runtime through
IPreparedModelCallback::notify. When the runtime retreives the
IPreparedModel object, the asynchronous task has already finished
preparing the model.

The two callbacks are used for different purposes. Each has its own
version of notify to pass the data back to the runtime:
* IPreparedModelCallback::notify(ErrorStatus, IPreparedModel)
* IExecutionCallback::notify(ErrorStatus)

Bug: 63905942
Test: mm, vts, ml/nn/runtime/tests
Change-Id: I0c88cd262ba762e0af15e9da31ebe813a5d150b2

1 files changed, 14 insertions, 7 deletions

diff --git a/neuralnetworks/1.0/Android.bp b/neuralnetworks/1.0/Android.bp
index d7c3bbbf72..ba32d0c396 100644
--- a/neuralnetworks/1.0/Android.bp
+++ b/neuralnetworks/1.0/Android.bp
@@ -5,8 +5,9 @@ filegroup {
     srcs: [
         "types.hal",
         "IDevice.hal",
-        "IEvent.hal",
+        "IExecutionCallback.hal",
         "IPreparedModel.hal",
+        "IPreparedModelCallback.hal",
     ],
 }
 
@@ -20,8 +21,9 @@ genrule {
     out: [
         "android/hardware/neuralnetworks/1.0/types.cpp",
         "android/hardware/neuralnetworks/1.0/DeviceAll.cpp",
-        "android/hardware/neuralnetworks/1.0/EventAll.cpp",
+        "android/hardware/neuralnetworks/1.0/ExecutionCallbackAll.cpp",
         "android/hardware/neuralnetworks/1.0/PreparedModelAll.cpp",
+        "android/hardware/neuralnetworks/1.0/PreparedModelCallbackAll.cpp",
     ],
 }
 
@@ -40,16 +42,21 @@ genrule {
         "android/hardware/neuralnetworks/1.0/BnHwDevice.h",
         "android/hardware/neuralnetworks/1.0/BpHwDevice.h",
         "android/hardware/neuralnetworks/1.0/BsDevice.h",
-        "android/hardware/neuralnetworks/1.0/IEvent.h",
-        "android/hardware/neuralnetworks/1.0/IHwEvent.h",
-        "android/hardware/neuralnetworks/1.0/BnHwEvent.h",
-        "android/hardware/neuralnetworks/1.0/BpHwEvent.h",
-        "android/hardware/neuralnetworks/1.0/BsEvent.h",
+        "android/hardware/neuralnetworks/1.0/IExecutionCallback.h",
+        "android/hardware/neuralnetworks/1.0/IHwExecutionCallback.h",
+        "android/hardware/neuralnetworks/1.0/BnHwExecutionCallback.h",
+        "android/hardware/neuralnetworks/1.0/BpHwExecutionCallback.h",
+        "android/hardware/neuralnetworks/1.0/BsExecutionCallback.h",
         "android/hardware/neuralnetworks/1.0/IPreparedModel.h",
         "android/hardware/neuralnetworks/1.0/IHwPreparedModel.h",
         "android/hardware/neuralnetworks/1.0/BnHwPreparedModel.h",
         "android/hardware/neuralnetworks/1.0/BpHwPreparedModel.h",
         "android/hardware/neuralnetworks/1.0/BsPreparedModel.h",
+        "android/hardware/neuralnetworks/1.0/IPreparedModelCallback.h",
+        "android/hardware/neuralnetworks/1.0/IHwPreparedModelCallback.h",
+        "android/hardware/neuralnetworks/1.0/BnHwPreparedModelCallback.h",
+        "android/hardware/neuralnetworks/1.0/BpHwPreparedModelCallback.h",
+        "android/hardware/neuralnetworks/1.0/BsPreparedModelCallback.h",
     ],
 }