[libcamera-devel] [PATCH v2 2/2] test: camera: Camera reconfiguration and fd-leak test

[paul.elder at ideasonboard.com]

Hi Umang,

On Wed, Aug 18, 2021 at 02:32:47PM +0530, Umang Jain wrote:
> This tests basically checks for two things:
> - Camera reconfigurations without stopping CameraManager
> - Fd leaks across IPA IPC boundary [1]
> 
> Currently, it uses vimc, but can be easily changed to using another
> platform (for e.g. IPU3) by changing kCamId_ and kIpaProxyName_.
> 
> The test performs kNumOfReconfigures_ (currently set to 10)
> reconfigurations of the camera. Each reconfiguration runs
> start(), capture(100ms), stop() of the camera. Hence, the test
> runs approximately for 1 second.
> 
> For checking the fd leaks, the test monitors the /proc/$PROXY_PID/fd
> directory for open fds. It compares the number of open fds after each
> run to the number of open fds before the first run. If those two are
> found to be mis-matched, the test shall report failure.
> 
> Since, the test needs to test the IPA IPC code paths, it is meant to
> always run with LIBCAMERA_IPA_FORCE_ISOLATION=1 environment variable.
> 
> [1] https://bugs.libcamera.org/show_bug.cgi?id=63
> 
> Signed-off-by: Umang Jain <umang.jain at ideasonboard.com>

Reviewed-by: Paul Elder <paul.elder at ideasonboard.com>

> ---
>  test/camera/camera_reconfigure.cpp | 255 +++++++++++++++++++++++++++++
>  test/camera/meson.build            |   1 +
>  2 files changed, 256 insertions(+)
>  create mode 100644 test/camera/camera_reconfigure.cpp
> 
> diff --git a/test/camera/camera_reconfigure.cpp b/test/camera/camera_reconfigure.cpp
> new file mode 100644
> index 00000000..90f798fe
> --- /dev/null
> +++ b/test/camera/camera_reconfigure.cpp
> @@ -0,0 +1,255 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later */
> +/*
> + * Copyright (C) 2021, Google Inc.
> + *
> + * Test:
> + * - Camera's multiple reconfigurations without stopping CameraManager
> + * - leaking fds across IPA IPC boundary
> + */
> +
> +#include <dirent.h>
> +#include <fstream>
> +#include <iostream>
> +
> +#include <libcamera/base/event_dispatcher.h>
> +#include <libcamera/base/file.h>
> +#include <libcamera/base/thread.h>
> +#include <libcamera/base/timer.h>
> +
> +#include <libcamera/framebuffer_allocator.h>
> +
> +#include "camera_test.h"
> +#include "test.h"
> +
> +using namespace std;
> +
> +namespace {
> +
> +class CameraReconfigure : public CameraTest, public Test
> +{
> +public:
> +	CameraReconfigure()
> +		: CameraTest(kCamId_, true)
> +	{
> +	}
> +
> +private:
> +	static constexpr const char *kCamId_ = "platform/vimc.0 Sensor B";
> +	static constexpr const char *kIpaProxyName_ = "vimc_ipa_proxy";
> +	static constexpr unsigned int kNumOfReconfigures_ = 10;
> +
> +	void requestComplete(Request *request)
> +	{
> +		if (request->status() != Request::RequestComplete)
> +			return;
> +
> +		const Request::BufferMap &buffers = request->buffers();
> +
> +		/* Create a new request. */
> +		const Stream *stream = buffers.begin()->first;
> +		FrameBuffer *buffer = buffers.begin()->second;
> +
> +		request->reuse();
> +		request->addBuffer(stream, buffer);
> +		camera_->queueRequest(request);
> +	}
> +
> +	int startAndStop()
> +	{
> +		StreamConfiguration &cfg = config_->at(0);
> +
> +		if (camera_->acquire()) {
> +			cerr << "Failed to acquire the camera" << endl;
> +			return TestFail;
> +		}
> +
> +		if (camera_->configure(config_.get())) {
> +			cerr << "Failed to set default configuration" << endl;
> +			return TestFail;
> +		}
> +
> +		Stream *stream = cfg.stream();
> +
> +		if (!allocated_) {
> +			int ret = allocator_->allocate(stream);
> +			if (ret < 0)
> +				return TestFail;
> +			allocated_ = true;
> +		}
> +
> +		for (const unique_ptr<FrameBuffer> &buffer : allocator_->buffers(stream)) {
> +			unique_ptr<Request> request = camera_->createRequest();
> +			if (!request) {
> +				cerr << "Failed to create request" << endl;
> +				return TestFail;
> +			}
> +
> +			if (request->addBuffer(stream, buffer.get())) {
> +				cerr << "Failed to associating buffer with request" << endl;
> +				return TestFail;
> +			}
> +
> +			requests_.push_back(move(request));
> +		}
> +
> +		camera_->requestCompleted.connect(this, &CameraReconfigure::requestComplete);
> +
> +		if (camera_->start()) {
> +			cerr << "Failed to start camera" << endl;
> +			return TestFail;
> +		}
> +
> +		for (unique_ptr<Request> &request : requests_) {
> +			if (camera_->queueRequest(request.get())) {
> +				cerr << "Failed to queue request" << endl;
> +				return TestFail;
> +			}
> +		}
> +
> +		EventDispatcher *dispatcher = Thread::current()->eventDispatcher();
> +
> +		Timer timer;
> +		timer.start(100);
> +		while (timer.isRunning())
> +			dispatcher->processEvents();
> +
> +		if (camera_->stop()) {
> +			cerr << "Failed to stop camera" << endl;
> +			return TestFail;
> +		}
> +
> +		if (camera_->release()) {
> +			cerr << "Failed to release camera" << endl;
> +			return TestFail;
> +		}
> +
> +		camera_->requestCompleted.disconnect(this, &CameraReconfigure::requestComplete);
> +
> +		requests_.clear();
> +
> +		return 0;
> +	}
> +
> +	int fdsOpen(pid_t pid)
> +	{
> +		string proxyFdPath = "/proc/" + to_string(pid) + "/fd";
> +		DIR *dir;
> +		struct dirent *ptr;
> +		unsigned int openFds = 0;
> +
> +		dir = opendir(proxyFdPath.c_str());
> +		if (dir == nullptr) {
> +			int err = errno;
> +			cerr << "Error opening " << proxyFdPath << ": "
> +			     << strerror(-err) << endl;
> +			return 0;
> +		}
> +
> +		while ((ptr = readdir(dir)) != nullptr) {
> +			if ((strcmp(ptr->d_name, ".") == 0) ||
> +			    (strcmp(ptr->d_name, "..") == 0))
> +				continue;
> +
> +			openFds++;
> +		}
> +		closedir(dir);
> +
> +		return openFds;
> +	}
> +
> +	pid_t findProxyPid()
> +	{
> +		string proxyPid;
> +		string proxyName(kIpaProxyName_);
> +		DIR *dir;
> +		struct dirent *ptr;
> +
> +		dir = opendir("/proc");
> +		while ((ptr = readdir(dir)) != nullptr) {
> +			if (ptr->d_type != DT_DIR)
> +				continue;
> +
> +			string pname("/proc/" + string(ptr->d_name) + "/comm");
> +			if (File::exists(pname.c_str())) {
> +				ifstream pfile(pname.c_str());
> +				string comm;
> +				getline(pfile, comm);
> +				pfile.close();
> +
> +				proxyPid = comm == proxyName ? string(ptr->d_name) : "";
> +			}
> +
> +			if (!proxyPid.empty())
> +				break;
> +		}
> +		closedir(dir);
> +
> +		if (!proxyPid.empty())
> +			return atoi(proxyPid.c_str());
> +
> +		return -1;
> +	}
> +
> +	int init() override
> +	{
> +		if (status_ != TestPass)
> +			return status_;
> +
> +		config_ = camera_->generateConfiguration({ StreamRole::StillCapture });
> +		if (!config_ || config_->size() != 1) {
> +			cerr << "Failed to generate default configuration" << endl;
> +			return TestFail;
> +		}
> +
> +		allocator_ = make_unique<FrameBufferAllocator>(camera_);
> +		allocated_ = false;
> +
> +		return TestPass;
> +	}
> +
> +	int run() override
> +	{
> +		unsigned int openFdsAtStart = 0;
> +		unsigned int openFds = 0;
> +
> +		pid_t proxyPid = findProxyPid();
> +		if (proxyPid < 0) {
> +			cerr << "Cannot find " << kIpaProxyName_
> +			     << " pid, exiting" << endl;
> +			return TestFail;
> +		}
> +
> +		openFdsAtStart = fdsOpen(proxyPid);
> +		for (unsigned int i = 0; i < kNumOfReconfigures_; i++) {
> +			startAndStop();
> +			openFds = fdsOpen(proxyPid);
> +			if (openFds == 0) {
> +				cerr << "No open fds found whereas "
> +				     << "open fds at start: " << openFdsAtStart
> +				     << endl;
> +				return TestFail;
> +			}
> +
> +			if (openFds != openFdsAtStart) {
> +				cerr << "Leaking fds for " << kIpaProxyName_
> +				     << " - Open fds: " << openFds << " vs "
> +				     << "Open fds at start: " << openFdsAtStart
> +				     << endl;
> +				return TestFail;
> +			}
> +		}
> +
> +		return TestPass;
> +	}
> +
> +	bool allocated_;
> +
> +	vector<unique_ptr<Request>> requests_;
> +
> +	unique_ptr<CameraConfiguration> config_;
> +	unique_ptr<FrameBufferAllocator> allocator_;
> +};
> +
> +} /* namespace */
> +
> +TEST_REGISTER(CameraReconfigure)
> diff --git a/test/camera/meson.build b/test/camera/meson.build
> index 002a87b5..668d5c03 100644
> --- a/test/camera/meson.build
> +++ b/test/camera/meson.build
> @@ -8,6 +8,7 @@ camera_tests = [
>      ['buffer_import',           'buffer_import.cpp'],
>      ['statemachine',            'statemachine.cpp'],
>      ['capture',                 'capture.cpp'],
> +    ['camera_reconfigure',      'camera_reconfigure.cpp'],
>  ]
>  
>  foreach t : camera_tests
> -- 
> 2.31.1
>