test/v4l2_videodevice/buffer_cache.cpp


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
 * Copyright (C) 2020, Google Inc.
 *
 * Test the buffer cache different operation modes
 */

#include <iostream>
#include <random>
#include <vector>

#include <libcamera/formats.h>
#include <libcamera/stream.h>

#include "buffer_source.h"

#include "test.h"

using namespace libcamera;

namespace {

class BufferCacheTest : public Test
{
public:
	/*
	 * Test that a cache with the same size as there are buffers results in
	 * a sequential run over; 0, 1, 2, 3, 4, 0, 1, 2, 3, 4, ...
	 *
	 * The test is only valid when the cache size is as least as big as the
	 * number of buffers.
	 */
	int testSequential(V4L2BufferCache *cache,
			   const std::vector<std::unique_ptr<FrameBuffer>> &buffers)
	{
		for (unsigned int i = 0; i < buffers.size() * 100; i++) {
			int nBuffer = i % buffers.size();
			int index = cache->get(*buffers[nBuffer].get());

			if (index != nBuffer) {
				std::cout << "Expected index " << nBuffer
					  << " got " << index << std::endl;
				return TestFail;
			}

			cache->put(index);
		}

		return TestPass;
	}

	/*
	 * Test that randomly putting buffers to the cache always results in a
	 * valid index.
	 */
	int testRandom(V4L2BufferCache *cache,
		       const std::vector<std::unique_ptr<FrameBuffer>> &buffers)
	{
		std::uniform_int_distribution<> dist(0, buffers.size() - 1);

		for (unsigned int i = 0; i < buffers.size() * 100; i++) {
			int nBuffer = dist(generator_);
			int index = cache->get(*buffers[nBuffer].get());

			if (index < 0) {
				std::cout << "Failed lookup from cache"
					  << std::endl;
				return TestFail;
			}

			cache->put(index);
		}

		return TestPass;
	}

	/*
	 * Test that using a buffer more frequently keeps it hot in the cache at
	 * all times.
	 */
	int testHot(V4L2BufferCache *cache,
		    const std::vector<std::unique_ptr<FrameBuffer>> &buffers,
		    unsigned int hotFrequency)
	{
		/* Run the random test on the cache to make it messy. */
		if (testRandom(cache, buffers) != TestPass)
			return TestFail;

		std::uniform_int_distribution<> dist(0, buffers.size() - 1);

		/* Pick a hot buffer at random and store its index. */
		int hotBuffer = dist(generator_);
		int hotIndex = cache->get(*buffers[hotBuffer].get());
		cache->put(hotIndex);

		/*
		 * Queue hot buffer at the requested frequency and make sure
		 * it stays hot.
		 */
		for (unsigned int i = 0; i < buffers.size() * 100; i++) {
			int nBuffer, index;
			bool hotQueue = i % hotFrequency == 0;

			if (hotQueue)
				nBuffer = hotBuffer;
			else
				nBuffer = dist(generator_);

			index = cache->get(*buffers[nBuffer].get());

			if (index < 0) {
				std::cout << "Failed lookup from cache"
					  << std::endl;
				return TestFail;
			}

			if (hotQueue && index != hotIndex) {
				std::cout << "Hot buffer got cold"
					  << std::endl;
				return TestFail;
			}

			cache->put(index);
		}

		return TestPass;
	}

	int testIsEmpty(const std::vector<std::unique_ptr<FrameBuffer>> &buffers)
	{
		V4L2BufferCache cache(buffers.size());

		if (!cache.isEmpty())
			return TestFail;

		for (auto const &buffer : buffers) {
			FrameBuffer &b = *buffer.get();
			cache.get(b);
		}

		if (cache.isEmpty())
			return TestFail;

		unsigned int i;
		for (i = 0; i < buffers.size() - 1; i++)
			cache.put(i);

		if (cache.isEmpty())
			return TestFail;

		cache.put(i);
		if (!cache.isEmpty())
			return TestFail;

		return TestPass;
	}

	int init() override
	{
		std::random_device rd;
		unsigned int seed = rd();

		std::cout << "Random seed is " << seed << std::endl;

		generator_.seed(seed);

		return TestPass;
	}

	int run() override
	{
		const unsigned int numBuffers = 8;

		StreamConfiguration cfg;
		cfg.pixelFormat = formats::YUYV;
		cfg.size = Size(600, 800);
		cfg.bufferCount = numBuffers;

		BufferSource source;
		int ret = source.allocate(cfg);
		if (ret != TestPass)
			return ret;

		const std::vector<std::unique_ptr<FrameBuffer>> &buffers =
			source.buffers();

		if (buffers.size() != numBuffers) {
			std::cout << "Got " << buffers.size()
				  << " buffers, expected " << numBuffers
				  << std::endl;
			return TestFail;
		}

		/*
		 * Test cache of same size as there are buffers, the cache is
		 * created from a list of buffers and will be pre-populated.
		 */
		V4L2BufferCache cacheFromBuffers(buffers);

		if (testSequential(&cacheFromBuffers, buffers) != TestPass)
			return TestFail;

		if (testRandom(&cacheFromBuffers, buffers) != TestPass)
			return TestFail;

		if (testHot(&cacheFromBuffers, buffers, numBuffers) != TestPass)
			return TestFail;

		/*
		 * Test cache of same size as there are buffers, the cache is
		 * not pre-populated.
		 */
		V4L2BufferCache cacheFromNumbers(numBuffers);

		if (testSequential(&cacheFromNumbers, buffers) != TestPass)
			return TestFail;

		if (testRandom(&cacheFromNumbers, buffers) != TestPass)
			return TestFail;

		if (testHot(&cacheFromNumbers, buffers, numBuffers) != TestPass)
			return TestFail;

		/*
		 * Test cache half the size of number of buffers used, the cache
		 * is not pre-populated.
		 */
		V4L2BufferCache cacheHalf(numBuffers / 2);

		if (testRandom(&cacheHalf, buffers) != TestPass)
			return TestFail;

		if (testHot(&cacheHalf, buffers, numBuffers / 2) != TestPass)
			return TestFail;

		/*
		 * Test that the isEmpty function reports the correct result at
		 * various levels of cache fullness.
		 */
		if (testIsEmpty(buffers) != TestPass)
			return TestFail;

		return TestPass;
	}

private:
	std::mt19937 generator_;
};

} /* namespace */

TEST_REGISTER(BufferCacheTest)
/* SPDX-License-Identifier: LGPL-2.1-or-later */
/*
 * Copyright (C) 2019, Google Inc.
 *
 * controls.cpp - Control handling
 */

#include <libcamera/controls.h>

#include <iomanip>
#include <sstream>
#include <string>
#include <string.h>

#include <libcamera/base/log.h>
#include <libcamera/base/utils.h>

#include "libcamera/internal/control_validator.h"

/**
 * \file controls.h
 * \brief Framework to manage controls related to an object
 *
 * A control is a mean to govern or influence the operation of an object, and in
 * particular of a camera. Every control is defined by a unique numerical ID, a
 * name string and the data type of the value it stores. The libcamera API
 * defines a set of standard controls in the libcamera::controls namespace, as
 * a set of instances of the Control class.
 *
 * The main way for applications to interact with controls is through the
 * ControlList stored in the Request class:
 *
 * \code{.cpp}
 * Request *req = ...;
 * ControlList &controls = req->controls();
 * controls->set(controls::AwbEnable, false);
 * controls->set(controls::ManualExposure, 1000);
 *
 * ...
 *
 * int32_t exposure = controls->get(controls::ManualExposure);
 * \endcode
 *
 * The ControlList::get() and ControlList::set() functions automatically deduce
 * the data type based on the control.
 */

namespace libcamera {

LOG_DEFINE_CATEGORY(Controls)

namespace {

static constexpr size_t ControlValueSize[] = {
	[ControlTypeNone]		= 0,
	[ControlTypeBool]		= sizeof(bool),
	[ControlTypeByte]		= sizeof(uint8_t),
	[ControlTypeInteger32]		= sizeof(int32_t),
	[ControlTypeInteger64]		= sizeof(int64_t),
	[ControlTypeFloat]		= sizeof(float),
	[ControlTypeString]		= sizeof(char),
	[ControlTypeRectangle]		= sizeof(Rectangle),
	[ControlTypeSize]		= sizeof(Size),
};

} /* namespace */

/**
 * \enum ControlType
 * \brief Define the data type of a Control
 * \var ControlTypeNone
 * Invalid type, for empty values
 * \var ControlTypeBool
 * The control stores a boolean value
 * \var ControlTypeByte
 * The control stores a byte value as an unsigned 8-bit integer
 * \var ControlTypeInteger32
 * The control stores a 32-bit integer value
 * \var ControlTypeInteger64
 * The control stores a 64-bit integer value
 * \var ControlTypeFloat
 * The control stores a 32-bit floating point value
 * \var ControlTypeString
 * The control stores a string value as an array of char
 */

/**
 * \class ControlValue
 * \brief Abstract type representing the value of a control
 */

/** \todo Revisit the ControlValue layout when stabilizing the ABI */
static_assert(sizeof(ControlValue) == 16, "Invalid size of ControlValue class");

/**
 * \brief Construct an empty ControlValue.
 */
ControlValue::ControlValue()
	: type_(ControlTypeNone), isArray_(false), numElements_(0)
{
}

/**
 * \fn template<typename T> T ControlValue::ControlValue(const T &value)
 * \brief Construct a ControlValue of type T
 * \param[in] value Initial value
 *
 * This function constructs a new instance of ControlValue and stores the \a
 * value inside it. If the type \a T is equivalent to Span<R>, the instance
 * stores an array of values of type \a R. Otherwise the instance stores a
 * single value of type \a T. The numElements() and type() are updated to
 * reflect the stored value.
 */

void ControlValue::release()
{
	std::size_t size = numElements_ * ControlValueSize[type_];

	if (size > sizeof(value_)) {
		delete[] reinterpret_cast<uint8_t *>(storage_);
		storage_ = nullptr;
	}
}

ControlValue::~ControlValue()
{
	release();
}

/**
 * \brief Construct a ControlValue with the content of \a other
 * \param[in] other The ControlValue to copy content from
 */
ControlValue::ControlValue(const ControlValue &other)
	: type_(ControlTypeNone), numElements_(0)
{
	*this = other;
}

/**
 * \brief Replace the content of the ControlValue with a copy of the content
 * of \a other
 * \param[in] other The ControlValue to copy content from
 * \return The ControlValue with its content replaced with the one of \a other
 */
ControlValue &ControlValue::operator=(const ControlValue &other)
{
	set(other.type_, other.isArray_, other.data().data(),
	    other.numElements_, ControlValueSize[other.type_]);
	return *this;
}

/**
 * \fn ControlValue::type()
 * \brief Retrieve the data type of the value
 * \return The value data type
 */

/**
 * \fn ControlValue::isNone()
 * \brief Determine if the value is not initialised
 * \return True if the value type is ControlTypeNone, false otherwise
 */

/**
 * \fn ControlValue::isArray()
 * \brief Determine if the value stores an array
 * \return True if the value stores an array, false otherwise
 */

/**
 * \fn ControlValue::numElements()
 * \brief Retrieve the number of elements stored in the ControlValue
 *
 * For instances storing an array, this function returns the number of elements
 * in the array. For instances storing a string, it returns the length of the
 * string, not counting the terminating '\0'. Otherwise, it returns 1.
 *
 * \return The number of elements stored in the ControlValue
 */

/**
 * \brief Retrieve the raw data of a control value
 * \return The raw data of the control value as a span of uint8_t
 */
Span<const uint8_t> ControlValue::data() const
{
	std::size_t size = numElements_ * ControlValueSize[type_];
	const uint8_t *data = size > sizeof(value_)
			    ? reinterpret_cast<const uint8_t *>(storage_)
			    : reinterpret_cast<const uint8_t *>(&value_);
	return { data, size };
}

/**
 * \copydoc ControlValue::data() const
 */
Span<uint8_t> ControlValue::data()
{
	Span<const uint8_t> data = const_cast<const ControlValue *>(this)->data();
	return { const_cast<uint8_t *>(data.data()), data.size() };
}

/**
 * \brief Assemble and return a string describing the value
 * \return A string describing the ControlValue
 */
std::string ControlValue::toString() const
{
	if (type_ == ControlTypeNone)
		return "<ValueType Error>";

	const uint8_t *data = ControlValue::data().data();

	if (type_ == ControlTypeString)
		return std::string(reinterpret_cast<const char *>(data),
				   numElements_);

	std::string str(isArray_ ? "[ " : "");

	for (unsigned int i = 0; i < numElements_; ++i) {
		switch (type_) {
		case ControlTypeBool: {
			const bool *value = reinterpret_cast<const bool *>(data);
			str += *value ? "true" : "false";
			break;
		}
		case ControlTypeByte: {
			const uint8_t *value = reinterpret_cast<const uint8_t *>(data);
			str += std::to_string(*value);
			break;
		}
		case ControlTypeInteger32: {
			const int32_t *value = reinterpret_cast<const int32_t *>(data);
			str += std::to_string(*value);
			break;
		}
		case ControlTypeInteger64: {
			const int64_t *value = reinterpret_cast<const int64_t *>(data);
			str += std::to_string(*value);
			break;
		}
		case ControlTypeFloat: {
			const float *value = reinterpret_cast<const float *>(data);
			str += std::to_string(*value);
			break;
		}
		case ControlTypeRectangle: {
			const Rectangle *value = reinterpret_cast<const Rectangle *>(data);
			str += value->toString();
			break;
		}
		case ControlTypeSize: {
			const Size *value = reinterpret_cast<const Size *>(data);
			str += value->toString();
			break;
		}
		case ControlTypeNone:
		case ControlTypeString:
			break;
		}

		if (i + 1 != numElements_)
			str += ", ";

		data += ControlValueSize[type_];
	}

	if (isArray_)
		str += " ]";

	return str;
}

/**
 * \brief Compare ControlValue instances for equality
 * \return True if the values have identical types and values, false otherwise
 */
bool ControlValue::operator==(const ControlValue &other) const
{
	if (type_ != other.type_)
		return false;

	if (numElements_ != other.numElements())
		return false;

	if (isArray_ != other.isArray_)
		return false;

	return memcmp(data().data(), other.data().data(), data().size()) == 0;
}

/**
 * \fn bool ControlValue::operator!=()
 * \brief Compare ControlValue instances for non equality
 * \return False if the values have identical types and values, true otherwise
 */

/**
 * \fn template<typename T> T ControlValue::get() const
 * \brief Get the control value
 *
 * This function returns the contained value as an instance of \a T. If the
 * ControlValue instance stores a single value, the type \a T shall match the
 * stored value type(). If the instance stores an array of values, the type
 * \a T should be equal to Span<const R>, and the type \a R shall match the
 * stored value type(). The behaviour is undefined otherwise.
 *
 * Note that a ControlValue instance that stores a non-array value is not
 * equivalent to an instance that stores an array value containing a single
 * element. The latter shall be accessed through a Span<const R> type, while
 * the former shall be accessed through a type \a T corresponding to type().
 *
 * \return The control value
 */

/**
 * \fn template<typename T> void ControlValue::set(const T &value)
 * \brief Set the control value to \a value
 * \param[in] value The control value
 *
 * This function stores the \a value in the instance. If the type \a T is
 * equivalent to Span<R>, the instance stores an array of values of type \a R.
 * Otherwise the instance stores a single value of type \a T. The numElements()
 * and type() are updated to reflect the stored value.
 *
 * The entire content of \a value is copied to the instance, no reference to \a
 * value or to the data it references is retained. This may be an expensive
 * operation for Span<> values that refer to large arrays.
 */

void ControlValue::set(ControlType type, bool isArray, const void *data,
		       std::size_t numElements, std::size_t elementSize)
{
	ASSERT(elementSize == ControlValueSize[type]);

	reserve(type, isArray, numElements);

	Span<uint8_t> storage = ControlValue::data();
	memcpy(storage.data(), data, storage.size());
}

/**
 * \brief Set the control type and reserve memory
 * \param[in] type The control type
 * \param[in] isArray True to make the value an array
 * \param[in] numElements The number of elements
 *
 * This function sets the type of the control value to \a type, and reserves
 * memory to store the control value. If \a isArray is true, the instance
 * becomes an array control and storage for \a numElements is reserved.
 * Otherwise the instance becomes a simple control, numElements is ignored, and
 * storage for the single element is reserved.
 */
void ControlValue::reserve(ControlType type, bool isArray, std::size_t numElements)
{
	if (!isArray)
		numElements = 1;

	std::size_t oldSize = numElements_ * ControlValueSize[type_];
	std::size_t newSize = numElements * ControlValueSize[type];

	if (oldSize != newSize)
		release();

	type_ = type;
	isArray_ = isArray;
	numElements_ = numElements;

	if (oldSize == newSize)
		return;

	if (newSize > sizeof(value_))
		storage_ = reinterpret_cast<void *>(new uint8_t[newSize]);
}

/**
 * \class ControlId
 * \brief Control static metadata
 *
 * The ControlId class stores a control ID, name and data type. It provides
 * unique identification of a control, but without support for compile-time
 * type deduction that the derived template Control class supports. See the
 * Control class for more information.
 */

/**
 * \fn ControlId::ControlId(unsigned int id, const std::string &name, ControlType type)
 * \brief Construct a ControlId instance
 * \param[in] id The control numerical ID
 * \param[in] name The control name
 * \param[in] type The control data type
 */

/**
 * \fn unsigned int ControlId::id() const
 * \brief Retrieve the control numerical ID
 * \return The control numerical ID
 */

/**
 * \fn const char *ControlId::name() const
 * \brief Retrieve the control name
 * \return The control name
 */

/**
 * \fn ControlType ControlId::type() const
 * \brief Retrieve the control data type
 * \return The control data type
 */

/**
 * \fn bool operator==(unsigned int lhs, const ControlId &rhs)
 * \brief Compare a ControlId with a control numerical ID
 * \param[in] lhs Left-hand side numerical ID
 * \param[in] rhs Right-hand side ControlId
 *
 * \return True if \a lhs is equal to \a rhs.id(), false otherwise
 */

/**
 * \fn bool operator==(const ControlId &lhs, unsigned int rhs)
 * \brief Compare a ControlId with a control numerical ID
 * \param[in] lhs Left-hand side ControlId
 * \param[in] rhs Right-hand side numerical ID
 *
 * \return True if \a lhs.id() is equal to \a rhs, false otherwise
 */

/**
 * \class Control
 * \brief Describe a control and its intrinsic properties
 *
 * The Control class models a control exposed by an object. Its template type
 * name T refers to the control data type, and allows functions that operate on
 * control values to be defined as template functions using the same type T for
 * the control value. See for instance how the ControlList::get() function
 * returns a value corresponding to the type of the requested control.
 *
 * While this class is the main means to refer to a control, the control
 * identifying information is stored in the non-template base ControlId class.
 * This allows code that operates on a set of controls of different types to
 * reference those controls through a ControlId instead of a Control. For
 * instance, the list of controls supported by a camera is exposed as ControlId
 * instead of Control.
 *
 * Controls of any type can be defined through template specialisation, but
 * libcamera only supports the bool, uint8_t, int32_t, int64_t and float types
 * natively (this includes types that are equivalent to the supported types,
 * such as int and long int).
 *
 * Controls IDs shall be unique. While nothing prevents multiple instances of
 * the Control class to be created with the same ID for the same object, doing
 * so may cause undefined behaviour.
 */

/**
 * \fn Control::Control(unsigned int id, const char *name)
 * \brief Construct a Control instance
 * \param[in] id The control numerical ID
 * \param[in] name The control name
 *
 * The control data type is automatically deduced from the template type T.
 */

/**
 * \typedef Control::type
 * \brief The Control template type T
 */

/**
 * \class ControlInfo
 * \brief Describe the limits of valid values for a Control
 *
 * The ControlInfo expresses the constraints on valid values for a control.
 * The constraints depend on the object the control applies to, and are
 * constant for the lifetime of that object. They are typically constructed by
 * pipeline handlers to describe the controls they support.
 */

/**
 * \brief Construct a ControlInfo with minimum and maximum range parameters
 * \param[in] min The control minimum value
 * \param[in] max The control maximum value
 * \param[in] def The control default value
 */
ControlInfo::ControlInfo(const ControlValue &min,
			 const ControlValue &max,
			 const ControlValue &def)
	: min_(min), max_(max), def_(def)
{
}

/**
 * \brief Construct a ControlInfo from the list of valid values
 * \param[in] values The control valid values
 * \param[in] def The control default value
 *
 * Construct a ControlInfo from a list of valid values. The ControlInfo
 * minimum and maximum values are set to the first and last members of the
 * values list respectively. The default value is set to \a def if provided, or
 * to the minimum value otherwise.
 */
ControlInfo::ControlInfo(Span<const ControlValue> values,
			 const ControlValue &def)
{
	min_ = values.front();
	max_ = values.back();
	def_ = !def.isNone() ? def : values.front();

	values_.reserve(values.size());
	for (const ControlValue &value : values)
		values_.push_back(value);
}

/**
 * \brief Construct a boolean ControlInfo with both boolean values
 * \param[in] values The control valid boolean values (both true and false)
 * \param[in] def The control default boolean value
 *
 * Construct a ControlInfo for a boolean control, where both true and false are
 * valid values. \a values must be { false, true } (the order is irrelevant).
 * The minimum value will always be false, and the maximum always true. The
 * default value is \a def.
 */
ControlInfo::ControlInfo(std::set<bool> values, bool def)
	: min_(false), max_(true), def_(def), values_({ false, true })
{
	ASSERT(values.count(def) && values.size() == 2);
}

/**
 * \brief Construct a boolean ControlInfo with only one valid value
 * \param[in] value The control valid boolean value
 *
 * Construct a ControlInfo for a boolean control, where there is only valid
 * value. The minimum, maximum, and default values will all be \a value.
 */
ControlInfo::ControlInfo(bool value)
	: min_(value), max_(value), def_(value)
{
	values_ = { value };
}

/**
 * \fn ControlInfo::min()
 * \brief Retrieve the minimum value of the control
 *
 * For string controls, this is the minimum length of the string, not counting
 * the terminating '\0'. For all other control types, this is the minimum value
 * of each element.
 *
 * \return A ControlValue with the minimum value for the control
 */

/**
 * \fn ControlInfo::max()
 * \brief Retrieve the maximum value of the control
 *
 * For string controls, this is the maximum length of the string, not counting
 * the terminating '\0'. For all other control types, this is the maximum value
 * of each element.
 *