open_toontown_panda3d/panda/src/pipeline/mutexSimpleImpl.cxx

74 lines
2.4 KiB
C++

// Filename: mutexSimpleImpl.cxx
// Created by: drose (19Jun07)
//
////////////////////////////////////////////////////////////////////
//
// PANDA 3D SOFTWARE
// Copyright (c) Carnegie Mellon University. All rights reserved.
//
// All use of this software is subject to the terms of the revised BSD
// license. You should have received a copy of this license along
// with this source code in a file named "LICENSE."
//
////////////////////////////////////////////////////////////////////
#include "selectThreadImpl.h"
#ifdef THREAD_SIMPLE_IMPL
#include "mutexSimpleImpl.h"
#include "threadSimpleImpl.h"
#include "threadSimpleManager.h"
////////////////////////////////////////////////////////////////////
// Function: MutexSimpleImpl::do_acquire
// Access: Private
// Description:
////////////////////////////////////////////////////////////////////
void MutexSimpleImpl::
do_acquire() {
// By the time we get here, we already know that someone else is
// holding the lock: (_flags & F_lock_count) != 0.
ThreadSimpleManager *manager = ThreadSimpleManager::get_global_ptr();
ThreadSimpleImpl *thread = manager->get_current_thread();
while ((_flags & F_lock_count) != 0) {
manager->enqueue_block(thread, this);
manager->next_context();
}
_flags |= F_lock_count;
}
////////////////////////////////////////////////////////////////////
// Function: MutexSimpleImpl::do_release
// Access: Private
// Description:
////////////////////////////////////////////////////////////////////
void MutexSimpleImpl::
do_release() {
// By the time we get here, we already know that someone else is
// blocked on this mutex: (_flags & F_waiters) != 0.
ThreadSimpleManager *manager = ThreadSimpleManager::get_global_ptr();
if (manager->unblock_one(this)) {
// There had been a thread waiting on this mutex. Switch contexts
// immediately, to make fairness more likely.
ThreadSimpleImpl *thread = manager->get_current_thread();
manager->enqueue_ready(thread, false);
manager->next_context();
}
}
////////////////////////////////////////////////////////////////////
// Function: MutexSimpleImpl::do_release_quietly
// Access: Private
// Description:
////////////////////////////////////////////////////////////////////
void MutexSimpleImpl::
do_release_quietly() {
ThreadSimpleManager *manager = ThreadSimpleManager::get_global_ptr();
manager->unblock_one(this);
}
#endif // THREAD_SIMPLE_IMPL