readerwriterqueue.h
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// ©2013-2015 Cameron Desrochers.
// Distributed under the simplified BSD license (see the license file that
// should have come with this header).
#pragma once
#include "atomicops.h"
#include <type_traits>
#include <utility>
#include <cassert>
#include <stdexcept>
#include <cstdint>
#include <cstdlib> // For malloc/free & size_t
// A lock-free queue for a single-consumer, single-producer architecture.
// The queue is also wait-free in the common path (except if more memory
// needs to be allocated, in which case malloc is called).
// Allocates memory sparingly (O(lg(n) times, amortized), and only once if
// the original maximum size estimate is never exceeded.
// Tested on x86/x64 processors, but semantics should be correct for all
// architectures (given the right implementations in atomicops.h), provided
// that aligned integer and pointer accesses are naturally atomic.
// Note that there should only be one consumer thread and producer thread;
// Switching roles of the threads, or using multiple consecutive threads for
// one role, is not safe unless properly synchronized.
// Using the queue exclusively from one thread is fine, though a bit silly.
#define CACHE_LINE_SIZE 64
#ifdef AE_VCPP
#pragma warning(push)
#pragma warning(disable: 4324) // structure was padded due to __declspec(align())
#pragma warning(disable: 4820) // padding was added
#pragma warning(disable: 4127) // conditional expression is constant
#endif
namespace moodycamel {
template<typename T, size_t MAX_BLOCK_SIZE = 512>
class ReaderWriterQueue
{
// Design: Based on a queue-of-queues. The low-level queues are just
// circular buffers with front and tail indices indicating where the
// next element to dequeue is and where the next element can be enqueued,
// respectively. Each low-level queue is called a "block". Each block
// wastes exactly one element's worth of space to keep the design simple
// (if front == tail then the queue is empty, and can't be full).
// The high-level queue is a circular linked list of blocks; again there
// is a front and tail, but this time they are pointers to the blocks.
// The front block is where the next element to be dequeued is, provided
// the block is not empty. The back block is where elements are to be
// enqueued, provided the block is not full.
// The producer thread owns all the tail indices/pointers. The consumer
// thread owns all the front indices/pointers. Both threads read each
// other's variables, but only the owning thread updates them. E.g. After
// the consumer reads the producer's tail, the tail may change before the
// consumer is done dequeuing an object, but the consumer knows the tail
// will never go backwards, only forwards.
// If there is no room to enqueue an object, an additional block (of
// equal size to the last block) is added. Blocks are never removed.
public:
// Constructs a queue that can hold maxSize elements without further
// allocations. If more than MAX_BLOCK_SIZE elements are requested,
// then several blocks of MAX_BLOCK_SIZE each are reserved (including
// at least one extra buffer block).
explicit ReaderWriterQueue(size_t maxSize = 15)
#ifndef NDEBUG
: enqueuing(false)
,dequeuing(false)
#endif
{
assert(maxSize > 0);
assert(MAX_BLOCK_SIZE == ceilToPow2(MAX_BLOCK_SIZE) && "MAX_BLOCK_SIZE must be a power of 2");
assert(MAX_BLOCK_SIZE >= 2 && "MAX_BLOCK_SIZE must be at least 2");
Block* firstBlock = nullptr;
largestBlockSize = ceilToPow2(maxSize + 1); // We need a spare slot to fit maxSize elements in the block
if (largestBlockSize > MAX_BLOCK_SIZE * 2) {
// We need a spare block in case the producer is writing to a different block the consumer is reading from, and
// wants to enqueue the maximum number of elements. We also need a spare element in each block to avoid the ambiguity
// between front == tail meaning "empty" and "full".
// So the effective number of slots that are guaranteed to be usable at any time is the block size - 1 times the
// number of blocks - 1. Solving for maxSize and applying a ceiling to the division gives us (after simplifying):
size_t initialBlockCount = (maxSize + MAX_BLOCK_SIZE * 2 - 3) / (MAX_BLOCK_SIZE - 1);
largestBlockSize = MAX_BLOCK_SIZE;
Block* lastBlock = nullptr;
for (size_t i = 0; i != initialBlockCount; ++i) {
auto block = make_block(largestBlockSize);
if (block == nullptr) {
throw std::bad_alloc();
}
if (firstBlock == nullptr) {
firstBlock = block;
}
else {
lastBlock->next = block;
}
lastBlock = block;
block->next = firstBlock;
}
}
else {
firstBlock = make_block(largestBlockSize);
if (firstBlock == nullptr) {
throw std::bad_alloc();
}
firstBlock->next = firstBlock;
}
frontBlock = firstBlock;
tailBlock = firstBlock;
// Make sure the reader/writer threads will have the initialized memory setup above:
fence(memory_order_sync);
}
// Note: The queue should not be accessed concurrently while it's
// being deleted. It's up to the user to synchronize this.
~ReaderWriterQueue()
{
// Make sure we get the latest version of all variables from other CPUs:
fence(memory_order_sync);
// Destroy any remaining objects in queue and free memory
Block* frontBlock_ = frontBlock;
Block* block = frontBlock_;
do {
Block* nextBlock = block->next;
size_t blockFront = block->front;
size_t blockTail = block->tail;
for (size_t i = blockFront; i != blockTail; i = (i + 1) & block->sizeMask) {
auto element = reinterpret_cast<T*>(block->data + i * sizeof(T));
element->~T();
(void)element;
}
auto rawBlock = block->rawThis;
block->~Block();
std::free(rawBlock);
block = nextBlock;
} while (block != frontBlock_);
}
// Enqueues a copy of element if there is room in the queue.
// Returns true if the element was enqueued, false otherwise.
// Does not allocate memory.
AE_FORCEINLINE bool try_enqueue(T const& element)
{
return inner_enqueue<CannotAlloc>(element);
}
// Enqueues a moved copy of element if there is room in the queue.
// Returns true if the element was enqueued, false otherwise.
// Does not allocate memory.
AE_FORCEINLINE bool try_enqueue(T&& element)
{
return inner_enqueue<CannotAlloc>(std::forward<T>(element));
}
// Enqueues a copy of element on the queue.
// Allocates an additional block of memory if needed.
// Only fails (returns false) if memory allocation fails.
AE_FORCEINLINE bool enqueue(T const& element)
{
return inner_enqueue<CanAlloc>(element);
}
// Enqueues a moved copy of element on the queue.
// Allocates an additional block of memory if needed.
// Only fails (returns false) if memory allocation fails.
AE_FORCEINLINE bool enqueue(T&& element)
{
return inner_enqueue<CanAlloc>(std::forward<T>(element));
}
// Attempts to dequeue an element; if the queue is empty,
// returns false instead. If the queue has at least one element,
// moves front to result using operator=, then returns true.
template<typename U>
bool try_dequeue(U& result)
{
#ifndef NDEBUG
ReentrantGuard guard(this->dequeuing);
#endif
// High-level pseudocode:
// Remember where the tail block is
// If the front block has an element in it, dequeue it
// Else
// If front block was the tail block when we entered the function, return false
// Else advance to next block and dequeue the item there
// Note that we have to use the value of the tail block from before we check if the front
// block is full or not, in case the front block is empty and then, before we check if the
// tail block is at the front block or not, the producer fills up the front block *and
// moves on*, which would make us skip a filled block. Seems unlikely, but was consistently
// reproducible in practice.
// In order to avoid overhead in the common case, though, we do a double-checked pattern
// where we have the fast path if the front block is not empty, then read the tail block,
// then re-read the front block and check if it's not empty again, then check if the tail
// block has advanced.
Block* frontBlock_ = frontBlock.load();
size_t blockTail = frontBlock_->localTail;
size_t blockFront = frontBlock_->front.load();
if (blockFront != blockTail || blockFront != (frontBlock_->localTail = frontBlock_->tail.load())) {
fence(memory_order_acquire);
non_empty_front_block:
// Front block not empty, dequeue from here
auto element = reinterpret_cast<T*>(frontBlock_->data + blockFront * sizeof(T));
result = std::move(*element);
element->~T();
blockFront = (blockFront + 1) & frontBlock_->sizeMask;
fence(memory_order_release);
frontBlock_->front = blockFront;
}
else if (frontBlock_ != tailBlock.load()) {
fence(memory_order_acquire);
frontBlock_ = frontBlock.load();
blockTail = frontBlock_->localTail = frontBlock_->tail.load();
blockFront = frontBlock_->front.load();
fence(memory_order_acquire);
if (blockFront != blockTail) {
// Oh look, the front block isn't empty after all
goto non_empty_front_block;
}
// Front block is empty but there's another block ahead, advance to it
Block* nextBlock = frontBlock_->next;
// Don't need an acquire fence here since next can only ever be set on the tailBlock,
// and we're not the tailBlock, and we did an acquire earlier after reading tailBlock which
// ensures next is up-to-date on this CPU in case we recently were at tailBlock.
size_t nextBlockFront = nextBlock->front.load();
size_t nextBlockTail = nextBlock->localTail = nextBlock->tail.load();
fence(memory_order_acquire);
// Since the tailBlock is only ever advanced after being written to,
// we know there's for sure an element to dequeue on it
assert(nextBlockFront != nextBlockTail);
AE_UNUSED(nextBlockTail);
// We're done with this block, let the producer use it if it needs
fence(memory_order_release); // Expose possibly pending changes to frontBlock->front from last dequeue
frontBlock = frontBlock_ = nextBlock;
compiler_fence(memory_order_release); // Not strictly needed
auto element = reinterpret_cast<T*>(frontBlock_->data + nextBlockFront * sizeof(T));
result = std::move(*element);
element->~T();
nextBlockFront = (nextBlockFront + 1) & frontBlock_->sizeMask;
fence(memory_order_release);
frontBlock_->front = nextBlockFront;
}
else {
// No elements in current block and no other block to advance to
return false;
}
return true;
}
// Returns a pointer to the front element in the queue (the one that
// would be removed next by a call to `try_dequeue` or `pop`). If the
// queue appears empty at the time the method is called, nullptr is
// returned instead.
// Must be called only from the consumer thread.
T* peek()
{
#ifndef NDEBUG
ReentrantGuard guard(this->dequeuing);
#endif
// See try_dequeue() for reasoning
Block* frontBlock_ = frontBlock.load();
size_t blockTail = frontBlock_->localTail;
size_t blockFront = frontBlock_->front.load();
if (blockFront != blockTail || blockFront != (frontBlock_->localTail = frontBlock_->tail.load())) {
fence(memory_order_acquire);
non_empty_front_block:
return reinterpret_cast<T*>(frontBlock_->data + blockFront * sizeof(T));
}
else if (frontBlock_ != tailBlock.load()) {
fence(memory_order_acquire);
frontBlock_ = frontBlock.load();
blockTail = frontBlock_->localTail = frontBlock_->tail.load();
blockFront = frontBlock_->front.load();
fence(memory_order_acquire);
if (blockFront != blockTail) {
goto non_empty_front_block;
}
Block* nextBlock = frontBlock_->next;
size_t nextBlockFront = nextBlock->front.load();
fence(memory_order_acquire);
assert(nextBlockFront != nextBlock->tail.load());
return reinterpret_cast<T*>(nextBlock->data + nextBlockFront * sizeof(T));
}
return nullptr;
}
// Removes the front element from the queue, if any, without returning it.
// Returns true on success, or false if the queue appeared empty at the time
// `pop` was called.
bool pop()
{
#ifndef NDEBUG
ReentrantGuard guard(this->dequeuing);
#endif
// See try_dequeue() for reasoning
Block* frontBlock_ = frontBlock.load();
size_t blockTail = frontBlock_->localTail;
size_t blockFront = frontBlock_->front.load();
if (blockFront != blockTail || blockFront != (frontBlock_->localTail = frontBlock_->tail.load())) {
fence(memory_order_acquire);
non_empty_front_block:
auto element = reinterpret_cast<T*>(frontBlock_->data + blockFront * sizeof(T));
element->~T();
blockFront = (blockFront + 1) & frontBlock_->sizeMask;
fence(memory_order_release);
frontBlock_->front = blockFront;
}
else if (frontBlock_ != tailBlock.load()) {
fence(memory_order_acquire);
frontBlock_ = frontBlock.load();
blockTail = frontBlock_->localTail = frontBlock_->tail.load();
blockFront = frontBlock_->front.load();
fence(memory_order_acquire);
if (blockFront != blockTail) {
goto non_empty_front_block;
}
// Front block is empty but there's another block ahead, advance to it
Block* nextBlock = frontBlock_->next;
size_t nextBlockFront = nextBlock->front.load();
size_t nextBlockTail = nextBlock->localTail = nextBlock->tail.load();
fence(memory_order_acquire);
assert(nextBlockFront != nextBlockTail);
AE_UNUSED(nextBlockTail);
fence(memory_order_release);
frontBlock = frontBlock_ = nextBlock;
compiler_fence(memory_order_release);
auto element = reinterpret_cast<T*>(frontBlock_->data + nextBlockFront * sizeof(T));
element->~T();
nextBlockFront = (nextBlockFront + 1) & frontBlock_->sizeMask;
fence(memory_order_release);
frontBlock_->front = nextBlockFront;
}
else {
// No elements in current block and no other block to advance to
return false;
}
return true;
}
// Returns the approximate number of items currently in the queue.
// Safe to call from both the producer and consumer threads.
inline size_t size_approx() const
{
size_t result = 0;
Block* frontBlock_ = frontBlock.load();
Block* block = frontBlock_;
do {
fence(memory_order_acquire);
size_t blockFront = block->front.load();
size_t blockTail = block->tail.load();
result += (blockTail - blockFront) & block->sizeMask;
block = block->next.load();
} while (block != frontBlock_);
return result;
}
private:
enum AllocationMode { CanAlloc, CannotAlloc };
template<AllocationMode canAlloc, typename U>
bool inner_enqueue(U&& element)
{
#ifndef NDEBUG
ReentrantGuard guard(this->enqueuing);
#endif
// High-level pseudocode (assuming we're allowed to alloc a new block):
// If room in tail block, add to tail
// Else check next block
// If next block is not the head block, enqueue on next block
// Else create a new block and enqueue there
// Advance tail to the block we just enqueued to
Block* tailBlock_ = tailBlock.load();
size_t blockFront = tailBlock_->localFront;
size_t blockTail = tailBlock_->tail.load();
size_t nextBlockTail = (blockTail + 1) & tailBlock_->sizeMask;
if (nextBlockTail != blockFront || nextBlockTail != (tailBlock_->localFront = tailBlock_->front.load())) {
fence(memory_order_acquire);
// This block has room for at least one more element
char* location = tailBlock_->data + blockTail * sizeof(T);
new (location) T(std::forward<U>(element));
fence(memory_order_release);
tailBlock_->tail = nextBlockTail;
}
else {
fence(memory_order_acquire);
if (tailBlock_->next.load() != frontBlock) {
// Note that the reason we can't advance to the frontBlock and start adding new entries there
// is because if we did, then dequeue would stay in that block, eventually reading the new values,
// instead of advancing to the next full block (whose values were enqueued first and so should be
// consumed first).
fence(memory_order_acquire); // Ensure we get latest writes if we got the latest frontBlock
// tailBlock is full, but there's a free block ahead, use it
Block* tailBlockNext = tailBlock_->next.load();
size_t nextBlockFront = tailBlockNext->localFront = tailBlockNext->front.load();
nextBlockTail = tailBlockNext->tail.load();
fence(memory_order_acquire);
// This block must be empty since it's not the head block and we
// go through the blocks in a circle
assert(nextBlockFront == nextBlockTail);
tailBlockNext->localFront = nextBlockFront;
char* location = tailBlockNext->data + nextBlockTail * sizeof(T);
new (location) T(std::forward<U>(element));
tailBlockNext->tail = (nextBlockTail + 1) & tailBlockNext->sizeMask;
fence(memory_order_release);
tailBlock = tailBlockNext;
}
else if (canAlloc == CanAlloc) {
// tailBlock is full and there's no free block ahead; create a new block
auto newBlockSize = largestBlockSize >= MAX_BLOCK_SIZE ? largestBlockSize : largestBlockSize * 2;
auto newBlock = make_block(newBlockSize);
if (newBlock == nullptr) {
// Could not allocate a block!
return false;
}
largestBlockSize = newBlockSize;
new (newBlock->data) T(std::forward<U>(element));
assert(newBlock->front == 0);
newBlock->tail = newBlock->localTail = 1;
newBlock->next = tailBlock_->next.load();
tailBlock_->next = newBlock;
// Might be possible for the dequeue thread to see the new tailBlock->next
// *without* seeing the new tailBlock value, but this is OK since it can't
// advance to the next block until tailBlock is set anyway (because the only
// case where it could try to read the next is if it's already at the tailBlock,
// and it won't advance past tailBlock in any circumstance).
fence(memory_order_release);
tailBlock = newBlock;
}
else if (canAlloc == CannotAlloc) {
// Would have had to allocate a new block to enqueue, but not allowed
return false;
}
else {
assert(false && "Should be unreachable code");
return false;
}
}
return true;
}
// Disable copying
ReaderWriterQueue(ReaderWriterQueue const&) { }
// Disable assignment
ReaderWriterQueue& operator=(ReaderWriterQueue const&) { }
AE_FORCEINLINE static size_t ceilToPow2(size_t x)
{
// From http://graphics.stanford.edu/~seander/bithacks.html#RoundUpPowerOf2
--x;
x |= x >> 1;
x |= x >> 2;
x |= x >> 4;
for (size_t i = 1; i < sizeof(size_t); i <<= 1) {
x |= x >> (i << 3);
}
++x;
return x;
}
template<typename U>
static AE_FORCEINLINE char* align_for(char* ptr)
{
const std::size_t alignment = std::alignment_of<U>::value;
return ptr + (alignment - (reinterpret_cast<std::uintptr_t>(ptr) % alignment)) % alignment;
}
private:
#ifndef NDEBUG
struct ReentrantGuard
{
ReentrantGuard(bool& _inSection)
: inSection(_inSection)
{
assert(!inSection);
if (inSection) {
throw std::runtime_error("ReaderWriterQueue does not support enqueuing or dequeuing elements from other elements' ctors and dtors");
}
inSection = true;
}
~ReentrantGuard() { inSection = false; }
private:
ReentrantGuard& operator=(ReentrantGuard const&);
private:
bool& inSection;
};
#endif
struct Block
{
// Avoid false-sharing by putting highly contended variables on their own cache lines
weak_atomic<size_t> front; // (Atomic) Elements are read from here
size_t localTail; // An uncontended shadow copy of tail, owned by the consumer
char cachelineFiller0[CACHE_LINE_SIZE - sizeof(weak_atomic<size_t>) - sizeof(size_t)];
weak_atomic<size_t> tail; // (Atomic) Elements are enqueued here
size_t localFront;
char cachelineFiller1[CACHE_LINE_SIZE - sizeof(weak_atomic<size_t>) - sizeof(size_t)]; // next isn't very contended, but we don't want it on the same cache line as tail (which is)
weak_atomic<Block*> next; // (Atomic)
char* data; // Contents (on heap) are aligned to T's alignment
const size_t sizeMask;
// size must be a power of two (and greater than 0)
Block(size_t const& _size, char* _rawThis, char* _data)
: front(0), localTail(0), tail(0), localFront(0), next(nullptr), data(_data), sizeMask(_size - 1), rawThis(_rawThis)
{
}
private:
// C4512 - Assignment operator could not be generated
Block& operator=(Block const&);
public:
char* rawThis;
};
static Block* make_block(size_t capacity)
{
// Allocate enough memory for the block itself, as well as all the elements it will contain
auto size = sizeof(Block) + std::alignment_of<Block>::value - 1;
size += sizeof(T) * capacity + std::alignment_of<T>::value - 1;
auto newBlockRaw = static_cast<char*>(std::malloc(size));
if (newBlockRaw == nullptr) {
return nullptr;
}
auto newBlockAligned = align_for<Block>(newBlockRaw);
auto newBlockData = align_for<T>(newBlockAligned + sizeof(Block));
return new (newBlockAligned) Block(capacity, newBlockRaw, newBlockData);
}
private:
weak_atomic<Block*> frontBlock; // (Atomic) Elements are enqueued to this block
char cachelineFiller[CACHE_LINE_SIZE - sizeof(weak_atomic<Block*>)];
weak_atomic<Block*> tailBlock; // (Atomic) Elements are dequeued from this block
size_t largestBlockSize;
#ifndef NDEBUG
bool enqueuing;
bool dequeuing;
#endif
};
// Like ReaderWriterQueue, but also providees blocking operations
template<typename T, size_t MAX_BLOCK_SIZE = 512>
class BlockingReaderWriterQueue
{
private:
typedef ::moodycamel::ReaderWriterQueue<T, MAX_BLOCK_SIZE> ReaderWriterQueue;
public:
explicit BlockingReaderWriterQueue(size_t maxSize = 15)
: inner(maxSize)
{ }
// Enqueues a copy of element if there is room in the queue.
// Returns true if the element was enqueued, false otherwise.
// Does not allocate memory.
AE_FORCEINLINE bool try_enqueue(T const& element)
{
if (inner.try_enqueue(element)) {
sema.signal();
return true;
}
return false;
}
// Enqueues a moved copy of element if there is room in the queue.
// Returns true if the element was enqueued, false otherwise.
// Does not allocate memory.
AE_FORCEINLINE bool try_enqueue(T&& element)
{
if (inner.try_enqueue(std::forward<T>(element))) {
sema.signal();
return true;
}
return false;
}
// Enqueues a copy of element on the queue.
// Allocates an additional block of memory if needed.
// Only fails (returns false) if memory allocation fails.
AE_FORCEINLINE bool enqueue(T const& element)
{
if (inner.enqueue(element)) {
sema.signal();
return true;
}
return false;
}
// Enqueues a moved copy of element on the queue.
// Allocates an additional block of memory if needed.
// Only fails (returns false) if memory allocation fails.
AE_FORCEINLINE bool enqueue(T&& element)
{
if (inner.enqueue(std::forward<T>(element))) {
sema.signal();
return true;
}
return false;
}
// Attempts to dequeue an element; if the queue is empty,
// returns false instead. If the queue has at least one element,
// moves front to result using operator=, then returns true.
template<typename U>
bool try_dequeue(U& result)
{
if (sema.tryWait()) {
bool success = inner.try_dequeue(result);
assert(success);
AE_UNUSED(success);
return true;
}
return false;
}
// Attempts to dequeue an element; if the queue is empty,
// waits until an element is available, then dequeues it.
template<typename U>
void wait_dequeue(U& result)
{
sema.wait();
bool success = inner.try_dequeue(result);
AE_UNUSED(result);
assert(success);
AE_UNUSED(success);
}
// Returns a pointer to the front element in the queue (the one that
// would be removed next by a call to `try_dequeue` or `pop`). If the
// queue appears empty at the time the method is called, nullptr is
// returned instead.
// Must be called only from the consumer thread.
AE_FORCEINLINE T* peek()
{
return inner.peek();
}
// Removes the front element from the queue, if any, without returning it.
// Returns true on success, or false if the queue appeared empty at the time
// `pop` was called.
AE_FORCEINLINE bool pop()
{
if (sema.tryWait()) {
bool result = inner.pop();
assert(result);
AE_UNUSED(result);
return true;
}
return false;
}
// Returns the approximate number of items currently in the queue.
// Safe to call from both the producer and consumer threads.
AE_FORCEINLINE size_t size_approx() const
{
return sema.availableApprox();
}
private:
// Disable copying & assignment
BlockingReaderWriterQueue(ReaderWriterQueue const&) { }
BlockingReaderWriterQueue& operator=(ReaderWriterQueue const&) { }
private:
ReaderWriterQueue inner;
spsc_sema::LightweightSemaphore sema;
};
} // end namespace moodycamel
#ifdef AE_VCPP
#pragma warning(pop)
#endif
atomicops.h
AE_UNUSED
#define AE_UNUSED(x)
Definition atomicops.h:41
AE_FORCEINLINE
#define AE_FORCEINLINE
Definition atomicops.h:51
moodycamel::BlockingReaderWriterQueue
Definition readerwriterqueue.h:629
moodycamel::BlockingReaderWriterQueue::peek
AE_FORCEINLINE T * peek()
Definition readerwriterqueue.h:723
moodycamel::BlockingReaderWriterQueue::enqueue
AE_FORCEINLINE bool enqueue(T const &element)
Definition readerwriterqueue.h:667
moodycamel::BlockingReaderWriterQueue::try_enqueue
AE_FORCEINLINE bool try_enqueue(T &&element)
Definition readerwriterqueue.h:654
moodycamel::BlockingReaderWriterQueue::size_approx
AE_FORCEINLINE size_t size_approx() const
Definition readerwriterqueue.h:744
moodycamel::BlockingReaderWriterQueue::pop
AE_FORCEINLINE bool pop()
Definition readerwriterqueue.h:731
moodycamel::BlockingReaderWriterQueue::wait_dequeue
void wait_dequeue(U &result)
Definition readerwriterqueue.h:708
moodycamel::BlockingReaderWriterQueue::try_enqueue
AE_FORCEINLINE bool try_enqueue(T const &element)
Definition readerwriterqueue.h:642
moodycamel::BlockingReaderWriterQueue::BlockingReaderWriterQueue
BlockingReaderWriterQueue(size_t maxSize=15)
Definition readerwriterqueue.h:634
moodycamel::BlockingReaderWriterQueue::try_dequeue
bool try_dequeue(U &result)
Definition readerwriterqueue.h:693
moodycamel::BlockingReaderWriterQueue::enqueue
AE_FORCEINLINE bool enqueue(T &&element)
Definition readerwriterqueue.h:679
moodycamel::ReaderWriterQueue
Definition readerwriterqueue.h:42
moodycamel::ReaderWriterQueue::size_approx
size_t size_approx() const
Definition readerwriterqueue.h:394
moodycamel::ReaderWriterQueue::pop
bool pop()
Definition readerwriterqueue.h:327
moodycamel::ReaderWriterQueue::ReaderWriterQueue
ReaderWriterQueue(size_t maxSize=15)
Definition readerwriterqueue.h:68
moodycamel::ReaderWriterQueue::peek
T * peek()
Definition readerwriterqueue.h:285
moodycamel::ReaderWriterQueue::try_enqueue
AE_FORCEINLINE bool try_enqueue(T const &element)
Definition readerwriterqueue.h:151
moodycamel::ReaderWriterQueue::enqueue
AE_FORCEINLINE bool enqueue(T const &element)
Definition readerwriterqueue.h:168
moodycamel::ReaderWriterQueue::enqueue
AE_FORCEINLINE bool enqueue(T &&element)
Definition readerwriterqueue.h:176
moodycamel::ReaderWriterQueue::try_enqueue
AE_FORCEINLINE bool try_enqueue(T &&element)
Definition readerwriterqueue.h:159
moodycamel::ReaderWriterQueue::try_dequeue
bool try_dequeue(U &result)
Definition readerwriterqueue.h:186
moodycamel::ReaderWriterQueue::~ReaderWriterQueue
~ReaderWriterQueue()
Definition readerwriterqueue.h:121
moodycamel::weak_atomic::load
AE_FORCEINLINE T load() const
Definition atomicops.h:293
moodycamel
Definition atomicops.h:68
moodycamel::memory_order_acquire
@ memory_order_acquire
Definition atomicops.h:72
moodycamel::memory_order_sync
@ memory_order_sync
Definition atomicops.h:79
moodycamel::memory_order_release
@ memory_order_release
Definition atomicops.h:73
moodycamel::fence
AE_FORCEINLINE void fence(memory_order order)
Definition atomicops.h:193
moodycamel::compiler_fence
AE_FORCEINLINE void compiler_fence(memory_order order)
Definition atomicops.h:181
CACHE_LINE_SIZE
#define CACHE_LINE_SIZE
Definition readerwriterqueue.h:29