yuzu/src/core/hle/kernel/mutex.cpp
2015-02-02 15:37:06 -02:00

86 lines
2.1 KiB
C++

// Copyright 2014 Citra Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#include <map>
#include <vector>
#include <boost/range/algorithm_ext/erase.hpp>
#include "common/common.h"
#include "core/hle/kernel/kernel.h"
#include "core/hle/kernel/mutex.h"
#include "core/hle/kernel/thread.h"
namespace Kernel {
/**
* Resumes a thread waiting for the specified mutex
* @param mutex The mutex that some thread is waiting on
*/
static void ResumeWaitingThread(Mutex* mutex) {
// Reset mutex lock thread handle, nothing is waiting
mutex->locked = false;
mutex->holding_thread = nullptr;
// Find the next waiting thread for the mutex...
auto next_thread = mutex->WakeupNextThread();
if (next_thread != nullptr) {
mutex->Acquire(next_thread);
}
}
void ReleaseThreadMutexes(Thread* thread) {
for (auto& mtx : thread->held_mutexes) {
ResumeWaitingThread(mtx.get());
}
thread->held_mutexes.clear();
}
ResultVal<SharedPtr<Mutex>> Mutex::Create(bool initial_locked, std::string name) {
SharedPtr<Mutex> mutex(new Mutex);
// TOOD(yuriks): Don't create Handle (see Thread::Create())
CASCADE_RESULT(auto unused, Kernel::g_handle_table.Create(mutex));
mutex->initial_locked = initial_locked;
mutex->locked = false;
mutex->name = std::move(name);
mutex->holding_thread = nullptr;
// Acquire mutex with current thread if initialized as locked...
if (initial_locked)
mutex->Acquire();
return MakeResult<SharedPtr<Mutex>>(mutex);
}
bool Mutex::ShouldWait() {
return locked && holding_thread != GetCurrentThread();
}
void Mutex::Acquire() {
Acquire(GetCurrentThread());
}
void Mutex::Acquire(Thread* thread) {
_assert_msg_(Kernel, !ShouldWait(), "object unavailable!");
if (locked)
return;
locked = true;
thread->held_mutexes.insert(this);
holding_thread = thread;
}
void Mutex::Release() {
if (!locked)
return;
holding_thread->held_mutexes.erase(this);
ResumeWaitingThread(this);
}
} // namespace