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

[Laurent Pinchart]

Hi Kieran,

On Wed, Feb 13, 2019 at 04:19:08PM +0000, Kieran Bingham wrote:
> On 13/02/2019 16:01, Laurent Pinchart wrote:
> > 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 ?
> 
> #include "log.h" removed :) (thus all LOGs)
> 
> >> +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_ ?
> 
> Sure.
> 
> >> +	unsigned int framesOutput;
> > 
> > framesOutput_ ?
> 
> Done.
> 
> >> +
> >> +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().
> 
> Really? format is a class? Shouldn't it's constructor do that?
> Hrm ... it has no constructor :(

Maybe we should turn it into a struct.

> >> +
> >> +		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 ?
> 
> That seems reasonable now.
> 
> Lets handle that separately though.
> 
> >> +		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.
> 
> Done
> 
> >> +	{
> >> +		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.
> 
> done
> 
> >> +		for (Buffer &b : pool_.buffers()) {
> > 
> > I'd spell buffer in full.
> 
> done
> 
> >> +			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" ?
> 
> Sure.
> 
> >> +
> >> +		dev_->streamOff();
> >> +		output_->streamOff();
> >> +
> >> +		if (secondMedia_)
> >> +			secondMedia_->release();
> > 
> > You should free buffers on both devices (for the capture device likely
> > in the base class).
> 
> Would you object to the destructor doing these things ? (as well?) as a
> catch all?

No objection, as long as we clean up properly and log errors
appropriately. It's important to test the cleanup paths too.

> >> +		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