Common: Implement a basic Fiber class.

This commit is contained in:
Fernando Sahmkow 2020-02-04 15:06:23 -04:00
parent 13ed9438fb
commit bc266a9d98
3 changed files with 204 additions and 0 deletions

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@ -110,6 +110,8 @@ add_library(common STATIC
common_types.h common_types.h
dynamic_library.cpp dynamic_library.cpp
dynamic_library.h dynamic_library.h
fiber.cpp
fiber.h
file_util.cpp file_util.cpp
file_util.h file_util.h
hash.h hash.h

147
src/common/fiber.cpp Normal file
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// Copyright 2020 yuzu Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#include "common/fiber.h"
namespace Common {
#ifdef _MSC_VER
#include <windows.h>
struct Fiber::FiberImpl {
LPVOID handle = nullptr;
};
void Fiber::_start([[maybe_unused]] void* parameter) {
guard.lock();
if (previous_fiber) {
previous_fiber->guard.unlock();
previous_fiber = nullptr;
}
entry_point(start_parameter);
}
static void __stdcall FiberStartFunc(LPVOID lpFiberParameter)
{
auto fiber = static_cast<Fiber *>(lpFiberParameter);
fiber->_start(nullptr);
}
Fiber::Fiber(std::function<void(void*)>&& entry_point_func, void* start_parameter)
: guard{}, entry_point{std::move(entry_point_func)}, start_parameter{start_parameter}, previous_fiber{} {
impl = std::make_unique<FiberImpl>();
impl->handle = CreateFiber(0, &FiberStartFunc, this);
}
Fiber::Fiber() : guard{}, entry_point{}, start_parameter{}, previous_fiber{} {
impl = std::make_unique<FiberImpl>();
}
Fiber::~Fiber() {
// Make sure the Fiber is not being used
guard.lock();
guard.unlock();
DeleteFiber(impl->handle);
}
void Fiber::Exit() {
if (!is_thread_fiber) {
return;
}
ConvertFiberToThread();
guard.unlock();
}
void Fiber::YieldTo(std::shared_ptr<Fiber> from, std::shared_ptr<Fiber> to) {
to->guard.lock();
to->previous_fiber = from;
SwitchToFiber(to->impl->handle);
auto previous_fiber = from->previous_fiber;
if (previous_fiber) {
previous_fiber->guard.unlock();
previous_fiber.reset();
}
}
std::shared_ptr<Fiber> Fiber::ThreadToFiber() {
std::shared_ptr<Fiber> fiber = std::shared_ptr<Fiber>{new Fiber()};
fiber->guard.lock();
fiber->impl->handle = ConvertThreadToFiber(NULL);
fiber->is_thread_fiber = true;
return fiber;
}
#else
#include <boost/context/detail/fcontext.hpp>
constexpr std::size_t default_stack_size = 1024 * 1024 * 4; // 4MB
struct Fiber::FiberImpl {
boost::context::detail::fcontext_t context;
std::array<u8, default_stack_size> stack;
};
void Fiber::_start(void* parameter) {
guard.lock();
boost::context::detail::transfer_t* transfer = static_cast<boost::context::detail::transfer_t*>(parameter);
if (previous_fiber) {
previous_fiber->impl->context = transfer->fctx;
previous_fiber->guard.unlock();
previous_fiber = nullptr;
}
entry_point(start_parameter);
}
static void FiberStartFunc(boost::context::detail::transfer_t transfer)
{
auto fiber = static_cast<Fiber *>(transfer.data);
fiber->_start(&transfer);
}
Fiber::Fiber(std::function<void(void*)>&& entry_point_func, void* start_parameter)
: guard{}, entry_point{std::move(entry_point_func)}, start_parameter{start_parameter}, previous_fiber{} {
impl = std::make_unique<FiberImpl>();
auto start_func = std::bind(&Fiber::start, this);
impl->context =
boost::context::detail::make_fcontext(impl->stack.data(), impl->stack.size(), &start_func);
}
Fiber::Fiber() : guard{}, entry_point{}, start_parameter{}, previous_fiber{} {
impl = std::make_unique<FiberImpl>();
}
Fiber::~Fiber() {
// Make sure the Fiber is not being used
guard.lock();
guard.unlock();
}
void Fiber::Exit() {
if (!is_thread_fiber) {
return;
}
guard.unlock();
}
void Fiber::YieldTo(std::shared_ptr<Fiber> from, std::shared_ptr<Fiber> to) {
to->guard.lock();
to->previous_fiber = from;
auto transfer = boost::context::detail::jump_fcontext(to->impl.context, nullptr);
auto previous_fiber = from->previous_fiber;
if (previous_fiber) {
previous_fiber->impl->context = transfer.fctx;
previous_fiber->guard.unlock();
previous_fiber.reset();
}
}
std::shared_ptr<Fiber> Fiber::ThreadToFiber() {
std::shared_ptr<Fiber> fiber = std::shared_ptr<Fiber>{new Fiber()};
fiber->is_thread_fiber = true;
return fiber;
}
#endif
} // namespace Common

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src/common/fiber.h Normal file
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// Copyright 2020 yuzu Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#pragma once
#include <functional>
#include <memory>
#include "common/common_types.h"
#include "common/spin_lock.h"
namespace Common {
class Fiber {
public:
Fiber(std::function<void(void*)>&& entry_point_func, void* start_parameter);
~Fiber();
Fiber(const Fiber&) = delete;
Fiber& operator=(const Fiber&) = delete;
Fiber(Fiber&&) = default;
Fiber& operator=(Fiber&&) = default;
/// Yields control from Fiber 'from' to Fiber 'to'
/// Fiber 'from' must be the currently running fiber.
static void YieldTo(std::shared_ptr<Fiber> from, std::shared_ptr<Fiber> to);
static std::shared_ptr<Fiber> ThreadToFiber();
/// Only call from main thread's fiber
void Exit();
/// Used internally but required to be public, Shall not be used
void _start(void* parameter);
/// Changes the start parameter of the fiber. Has no effect if the fiber already started
void SetStartParameter(void* new_parameter) {
start_parameter = new_parameter;
}
private:
Fiber();
struct FiberImpl;
SpinLock guard;
std::function<void(void*)> entry_point;
void* start_parameter;
std::shared_ptr<Fiber> previous_fiber;
std::unique_ptr<FiberImpl> impl;
bool is_thread_fiber{};
};
} // namespace Common