100 lines
2.5 KiB
C++
100 lines
2.5 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->lock_count = 0;
|
|
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();
|
|
}
|
|
|
|
Mutex::Mutex() {}
|
|
Mutex::~Mutex() {}
|
|
|
|
SharedPtr<Mutex> Mutex::Create(bool initial_locked, std::string name) {
|
|
SharedPtr<Mutex> mutex(new Mutex);
|
|
|
|
mutex->lock_count = 0;
|
|
mutex->name = std::move(name);
|
|
mutex->holding_thread = nullptr;
|
|
|
|
// Acquire mutex with current thread if initialized as locked...
|
|
if (initial_locked)
|
|
mutex->Acquire();
|
|
|
|
return mutex;
|
|
}
|
|
|
|
bool Mutex::ShouldWait() {
|
|
auto thread = GetCurrentThread();
|
|
bool wait = lock_count > 0 && holding_thread != thread;
|
|
|
|
// If the holding thread of the mutex is lower priority than this thread, that thread should
|
|
// temporarily inherit this thread's priority
|
|
if (wait && thread->current_priority < holding_thread->current_priority)
|
|
holding_thread->BoostPriority(thread->current_priority);
|
|
|
|
return wait;
|
|
}
|
|
|
|
void Mutex::Acquire() {
|
|
Acquire(GetCurrentThread());
|
|
}
|
|
|
|
void Mutex::Acquire(SharedPtr<Thread> thread) {
|
|
ASSERT_MSG(!ShouldWait(), "object unavailable!");
|
|
|
|
// Actually "acquire" the mutex only if we don't already have it...
|
|
if (lock_count == 0) {
|
|
thread->held_mutexes.insert(this);
|
|
holding_thread = std::move(thread);
|
|
}
|
|
|
|
lock_count++;
|
|
}
|
|
|
|
void Mutex::Release() {
|
|
// Only release if the mutex is held...
|
|
if (lock_count > 0) {
|
|
lock_count--;
|
|
|
|
// Yield to the next thread only if we've fully released the mutex...
|
|
if (lock_count == 0) {
|
|
holding_thread->held_mutexes.erase(this);
|
|
ResumeWaitingThread(this);
|
|
}
|
|
}
|
|
}
|
|
|
|
} // namespace
|