[libcamera-devel] [PATCH v2 8/8] test: v4l2_device: Provide buffer sharing test

[Laurent Pinchart]

Hi Kieran,

Thank you for the patch.

On Wed, Feb 13, 2019 at 03:10:27PM +0000, Kieran Bingham wrote:
> Obtain two V4L2Devices and use one to obtain a BufferPool.
> 
> Propagate the formats from the first to the second device and then commence
> sending buffers between the two devices in a ping-pong fashion.
> 
> Signed-off-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
> ---
>  test/v4l2_device/buffer_sharing.cpp | 179 ++++++++++++++++++++++++++++
>  test/v4l2_device/meson.build        |   1 +
>  2 files changed, 180 insertions(+)
>  create mode 100644 test/v4l2_device/buffer_sharing.cpp
> 
> diff --git a/test/v4l2_device/buffer_sharing.cpp b/test/v4l2_device/buffer_sharing.cpp
> new file mode 100644
> index 000000000000..f03201e82084
> --- /dev/null
> +++ b/test/v4l2_device/buffer_sharing.cpp
> @@ -0,0 +1,179 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later */
> +/*
> + * Copyright (C) 2019, Google Inc.
> + *
> + * libcamera V4L2 API tests
> + *
> + * Validate the function of exporting buffers from a V4L2Device and
> + * the ability to import them to another V4L2Device instance.
> + * Ensure that the Buffers can successfully be queued and dequeued
> + * between both devices.
> + */
> +
> +#include <iostream>
> +
> +#include <libcamera/buffer.h>
> +#include <libcamera/camera_manager.h>
> +#include <libcamera/event_dispatcher.h>
> +#include <libcamera/timer.h>
> +
> +#include "v4l2_device_test.h"
> +
> +#include "log.h"
> +
> +LOG_DEFINE_CATEGORY(Test)

Can you use std::cout until we implement a test logger ?

> +class BufferSharingTest : public V4L2DeviceTest
> +{
> +public:
> +	BufferSharingTest()
> +		: output_(nullptr), framesCapture(0), framesOutput(0){};

	BufferSharingTest()
		: V4L2DeviceTest(), output_(nullptr), framesCapture(0),
		  framesOutput(0)
	{
	}

> +
> +private:
> +	const unsigned int bufferCount = 4;
> +
> +	V4L2Device *output_;
> +	std::shared_ptr<MediaDevice> secondMedia_;

This can be removed.

> +
> +	unsigned int framesCapture;

framesCaptured_ ?

> +	unsigned int framesOutput;

framesOutput_ ?

> +
> +protected:
> +	int init()
> +	{
> +		int ret = V4L2DeviceTest::init();
> +		if (ret)
> +			return ret;
> +
> +		/* media_ already represents VIVID */
> +		MediaEntity *entity = media_->getEntityByName("vivid-000-vid-out");
> +		if (!entity)
> +			return TestSkip;
> +
> +		output_ = new V4L2Device(entity);
> +		if (!output_)
> +			return TestFail;
> +
> +		ret = output_->open();
> +		if (ret)
> +			return TestFail;
> +
> +		V4L2DeviceFormat format;

You should either initialise format to all 0 here (format = {}) or do so
in V4L2Device::getFormat().

> +
> +		ret = dev_->getFormat(&format);
> +		if (ret) {
> +			return TestFail;
> +		}

No need for braces. Or rather please keep them and log a message
explaining the cause of the error. Same for the other TestFail above and
below.

> +
> +		LOG(Test, Info) << "Successfully obtained format from source";

If we log failures I think you can remove this and the other LOG()
instance below.

> +		ret = output_->setFormat(&format);
> +		if (ret)
> +			return TestFail;
> +
> +		LOG(Test, Info) << "Successfully set format to output";
> +
> +		pool_.createBuffers(bufferCount);
> +
> +		ret = dev_->exportBuffers(&pool_);

Should we rename dev_ to capture_ in the base class ?

> +		if (ret)
> +			return TestFail;
> +
> +		ret = output_->importBuffers(&pool_);
> +		if (ret) {
> +			std::cerr << "Failed to import buffers" << std::endl;
> +			return TestFail;
> +		}
> +
> +		return 0;
> +	}
> +
> +	void receiveSourceBuffer(Buffer *buffer)

How about captureBufferReady() ?

> +	{
> +		std::cout << "Received source buffer: " << buffer->index()
> +			  << " sequence " << buffer->sequence() << std::endl;
> +
> +		output_->queueBuffer(buffer);
> +		framesCapture++;
> +	}
> +
> +	void receiveDestinationBuffer(Buffer *buffer)

And outputBufferReady() ?

Source and destination could be a bit confusing. I'd rework the messages
accordingly.

> +	{
> +		std::cout << "Received destination buffer: " << buffer->index()
> +			  << " sequence " << buffer->sequence() << std::endl;
> +
> +		dev_->queueBuffer(buffer);
> +		framesOutput++;
> +	}
> +
> +	int run()
> +	{
> +		EventDispatcher *dispatcher = CameraManager::instance()->eventDispatcher();
> +		Timer timeout;
> +		int ret;
> +
> +		dev_->bufferReady.connect(this, &BufferSharingTest::receiveSourceBuffer);
> +		output_->bufferReady.connect(this, &BufferSharingTest::receiveDestinationBuffer);
> +
> +		/* Queue all the buffers to the device. */

... to the capture device.

> +		for (Buffer &b : pool_.buffers()) {

I'd spell buffer in full.

> +			if (dev_->queueBuffer(&b))
> +				return TestFail;
> +		}
> +
> +		ret = dev_->streamOn();
> +		if (ret)
> +			return TestFail;
> +
> +		ret = output_->streamOn();
> +		if (ret)
> +			return TestFail;
> +
> +		timeout.start(10000);
> +		while (timeout.isRunning()) {
> +			dispatcher->processEvents();
> +			if (framesCapture > 30 && framesOutput > 30)
> +				break;
> +		}
> +
> +		if ((framesCapture < 1) || (framesOutput < 1)) {
> +			std::cout << "Failed to process any frames within timeout." << std::endl;
> +			return TestFail;
> +		}
> +
> +		if ((framesCapture < 30) || (framesOutput < 30)) {
> +			std::cout << "Failed to process 30 frames within timeout." << std::endl;
> +			return TestFail;
> +		}
> +
> +		ret = dev_->streamOff();
> +		if (ret)
> +			return TestFail;
> +
> +		ret = output_->streamOff();
> +		if (ret)
> +			return TestFail;
> +
> +		return TestPass;
> +	}
> +
> +	void cleanup()
> +	{
> +		std::cout
> +			<< "Processed " << framesCapture << " capture frames"
> +			<< " and " << framesOutput << " output frames"
> +			<< std::endl;

Maybe "Captured ... frames and output ... frames" ?

> +
> +		dev_->streamOff();
> +		output_->streamOff();
> +
> +		if (secondMedia_)
> +			secondMedia_->release();

You should free buffers on both devices (for the capture device likely
in the base class).

> +		delete output_;
> +
> +		V4L2DeviceTest::cleanup();
> +	}
> +};
> +
> +TEST_REGISTER(BufferSharingTest);
> diff --git a/test/v4l2_device/meson.build b/test/v4l2_device/meson.build
> index ec2c7f9f11ff..9f7a7545ac9b 100644
> --- a/test/v4l2_device/meson.build
> +++ b/test/v4l2_device/meson.build
> @@ -5,6 +5,7 @@ v4l2_device_tests = [
>    [ 'request_buffers',    'request_buffers.cpp' ],
>    [ 'stream_on_off',      'stream_on_off.cpp' ],
>    [ 'capture_async',      'capture_async.cpp' ],
> +  [ 'buffer_sharing',     'buffer_sharing.cpp' ],
>  ]
>  
>  foreach t : v4l2_device_tests

-- 
Regards,

Laurent Pinchart