android: Track and notify post processing of streams

Notify that the post processing for a request has been completed,
via a signal. The signal is emitted with a context pointer along with
status of the buffer. The function CameraDevice::streamProcessingComplete()
will finally set the status on the request descriptor and complete the
descriptor if all the streams requiring post processing are completed.
If buffer status obtained is in error state, notify the status to the
framework and set the overall error status on the descriptor via
setBufferStatus().

We need to track the number of streams requiring post-processing
per Camera3RequestDescriptor (i.e. per capture request). Introduce
a std::map to track the post-processing of streams. The nodes
are dropped from the map when a particular stream post processing
is completed (or on error paths). A std::map is selected for tracking
post-processing requests, since we will move post-processing to be
asynchronous in subsequent commits. A vector or queue will not be
suitable as the sequential order of post-processing completion
of various requests won't be guaranteed then.

A streamsProcessMutex_ has been introduced here as well, which will be
applicable to guard access to descriptor's pendingStreamsToProcess_ when
post-processing is moved to be asynchronous in subsequent commits.

Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Hirokazu Honda <hiroh@chromium.org>

1 files changed, 63 insertions, 24 deletions

diff --git a/src/android/camera_device.cpp b/src/android/camera_device.cpp
index 9155728a..fed539f3 100644
--- a/src/android/camera_device.cpp
+++ b/src/android/camera_device.cpp
@@ -926,6 +926,9 @@ int CameraDevice::processCaptureRequest(camera3_capture_request_t *camera3Reques
 			 * Request.
 			 */
 			LOG(HAL, Debug) << ss.str() << " (mapped)";
+
+			descriptor->pendingStreamsToProcess_.insert(
+				{ cameraStream, &buffer });
 			continue;
 
 		case CameraStream::Type::Direct:
@@ -955,6 +958,9 @@ int CameraDevice::processCaptureRequest(camera3_capture_request_t *camera3Reques
 			frameBuffer = cameraStream->getBuffer();
 			buffer.internalBuffer = frameBuffer;
 			LOG(HAL, Debug) << ss.str() << " (internal)";
+
+			descriptor->pendingStreamsToProcess_.insert(
+				{ cameraStream, &buffer });
 			break;
 		}
 
@@ -1118,42 +1124,42 @@ void CameraDevice::requestComplete(Request *request)
 	}
 
 	/* Handle post-processing. */
-	for (auto &buffer : descriptor->buffers_) {
-		CameraStream *stream = buffer.stream;
-
-		if (stream->type() == CameraStream::Type::Direct)
-			continue;
+	/*
+	 * \todo Protect the loop below with streamsProcessMutex_ when post
+	 * processor runs asynchronously.
+	 */
+	auto iter = descriptor->pendingStreamsToProcess_.begin();
+	while (iter != descriptor->pendingStreamsToProcess_.end()) {
+		CameraStream *stream = iter->first;
+		Camera3RequestDescriptor::StreamBuffer *buffer = iter->second;
 
 		FrameBuffer *src = request->findBuffer(stream->stream());
 		if (!src) {
 			LOG(HAL, Error) << "Failed to find a source stream buffer";
-			buffer.status = Camera3RequestDescriptor::Status::Error;
-			notifyError(descriptor->frameNumber_, stream->camera3Stream(),
-				    CAMERA3_MSG_ERROR_BUFFER);
-			descriptor->status_ = Camera3RequestDescriptor::Status::Error;
+			setBufferStatus(*buffer, Camera3RequestDescriptor::Status::Error);
+			iter = descriptor->pendingStreamsToProcess_.erase(iter);
 			continue;
 		}
 
-		buffer.srcBuffer = src;
-
-		int ret = stream->process(&buffer);
-
-		/*
-		 * If the framebuffer is internal to CameraStream return it back
-		 * now that we're done processing it.
-		 */
-		if (buffer.internalBuffer)
-			stream->putBuffer(buffer.internalBuffer);
+		buffer->srcBuffer = src;
 
+		++iter;
+		int ret = stream->process(buffer);
 		if (ret) {
-			buffer.status = Camera3RequestDescriptor::Status::Error;
-			notifyError(descriptor->frameNumber_, stream->camera3Stream(),
-				    CAMERA3_MSG_ERROR_BUFFER);
-			descriptor->status_ = Camera3RequestDescriptor::Status::Error;
+			setBufferStatus(*buffer, Camera3RequestDescriptor::Status::Error);
+			descriptor->pendingStreamsToProcess_.erase(stream);
+
+			/*
+			 * If the framebuffer is internal to CameraStream return
+			 * it back now that we're done processing it.
+			 */
+			if (buffer->internalBuffer)
+				stream->putBuffer(buffer->internalBuffer);
 		}
 	}
 
-	completeDescriptor(descriptor);
+	if (descriptor->pendingStreamsToProcess_.empty())
+		completeDescriptor(descriptor);
 }
 
 void CameraDevice::completeDescriptor(Camera3RequestDescriptor *descriptor)
@@ -1208,6 +1214,39 @@ void CameraDevice::sendCaptureResults()
 	}
 }
 
+void CameraDevice::setBufferStatus(Camera3RequestDescriptor::StreamBuffer &streamBuffer,
+				   Camera3RequestDescriptor::Status status)
+{
+	streamBuffer.status = status;
+	if (status != Camera3RequestDescriptor::Status::Success) {
+		notifyError(streamBuffer.request->frameNumber_,
+			    streamBuffer.stream->camera3Stream(),
+			    CAMERA3_MSG_ERROR_BUFFER);
+
+		/* Also set error status on entire request descriptor. */
+		streamBuffer.request->status_ =
+			Camera3RequestDescriptor::Status::Error;
+	}
+}
+
+void CameraDevice::streamProcessingComplete(Camera3RequestDescriptor::StreamBuffer *streamBuffer,
+					    Camera3RequestDescriptor::Status status)
+{
+	setBufferStatus(*streamBuffer, status);
+
+	/*
+	 * If the framebuffer is internal to CameraStream return it back now
+	 * that we're done processing it.
+	 */
+	if (streamBuffer->internalBuffer)
+		streamBuffer->stream->putBuffer(streamBuffer->internalBuffer);
+
+	Camera3RequestDescriptor *request = streamBuffer->request;
+	MutexLocker locker(request->streamsProcessMutex_);
+
+	request->pendingStreamsToProcess_.erase(streamBuffer->stream);
+}
+
 std::string CameraDevice::logPrefix() const
 {
 	return "'" + camera_->id() + "'";