if (SpNode)
{
moveCount = ++sp->moveCount;
- lock_release(sp->lock);
+ sp->mutex.unlock();
}
else
moveCount++;
&& (!threatMove || !connected_threat(pos, move, threatMove)))
{
if (SpNode)
- lock_grab(sp->lock);
+ sp->mutex.lock();
continue;
}
if (futilityValue < beta)
{
if (SpNode)
- lock_grab(sp->lock);
+ sp->mutex.lock();
continue;
}
&& pos.see_sign(move) < 0)
{
if (SpNode)
- lock_grab(sp->lock);
+ sp->mutex.lock();
continue;
}
// Step 18. Check for new best move
if (SpNode)
{
- lock_grab(sp->lock);
+ sp->mutex.lock();
bestValue = sp->bestValue;
alpha = sp->alpha;
}
}
// Grab the lock to avoid races with Thread::wake_up()
- lock_grab(sleepLock);
+ mutex.lock();
// If we are master and all slaves have finished don't go to sleep
if (sp_master && !sp_master->slavesMask)
{
- lock_release(sleepLock);
+ mutex.unlock();
break;
}
// in the meanwhile, allocated us and sent the wake_up() call before we
// had the chance to grab the lock.
if (do_sleep || !is_searching)
- cond_wait(sleepCond, sleepLock);
+ sleepCondition.wait(mutex);
- lock_release(sleepLock);
+ mutex.unlock();
}
// If this thread has been assigned work, launch a search
{
assert(!do_sleep && !do_exit);
- lock_grab(Threads.splitLock);
+ Threads.mutex.lock();
assert(is_searching);
SplitPoint* sp = curSplitPoint;
- lock_release(Threads.splitLock);
+ Threads.mutex.unlock();
Stack ss[MAX_PLY_PLUS_2];
Position pos(*sp->pos, this);
memcpy(ss, sp->ss - 1, 4 * sizeof(Stack));
(ss+1)->sp = sp;
- lock_grab(sp->lock);
+ sp->mutex.lock();
if (sp->nodeType == Root)
search<SplitPointRoot>(pos, ss+1, sp->alpha, sp->beta, sp->depth);
// related data in a safe way becuase it could have been released under
// our feet by the sp master. Also accessing other Thread objects is
// unsafe because if we are exiting there is a chance are already freed.
- lock_release(sp->lock);
+ sp->mutex.unlock();
}
}
}
do_sleep = (fn != &Thread::main_loop); // Avoid a race with start_searching()
- lock_init(sleepLock);
- cond_init(sleepCond);
-
- for (int j = 0; j < MAX_SPLITPOINTS_PER_THREAD; j++)
- lock_init(splitPoints[j].lock);
-
if (!thread_create(handle, start_routine, this))
{
std::cerr << "Failed to create thread number " << idx << std::endl;
do_exit = true; // Search must be already finished
wake_up();
-
thread_join(handle); // Wait for thread termination
-
- lock_destroy(sleepLock);
- cond_destroy(sleepCond);
-
- for (int j = 0; j < MAX_SPLITPOINTS_PER_THREAD; j++)
- lock_destroy(splitPoints[j].lock);
}
while (!do_exit)
{
- lock_grab(sleepLock);
- timed_wait(sleepCond, sleepLock, maxPly ? maxPly : INT_MAX);
- lock_release(sleepLock);
+ mutex.lock();
+ sleepCondition.wait_for(mutex, maxPly ? maxPly : INT_MAX);
+ mutex.unlock();
check_time();
}
}
while (true)
{
- lock_grab(sleepLock);
+ mutex.lock();
do_sleep = true; // Always return to sleep after a search
is_searching = false;
while (do_sleep && !do_exit)
{
- cond_signal(Threads.sleepCond); // Wake up UI thread if needed
- cond_wait(sleepCond, sleepLock);
+ Threads.sleepCondition.notify_one(); // Wake up UI thread if needed
+ sleepCondition.wait(mutex);
}
- lock_release(sleepLock);
+ mutex.unlock();
if (do_exit)
return;
void Thread::wake_up() {
- lock_grab(sleepLock);
- cond_signal(sleepCond);
- lock_release(sleepLock);
+ mutex.lock();
+ sleepCondition.notify_one();
+ mutex.unlock();
}
Signals.stopOnPonderhit = true;
- lock_grab(sleepLock);
- while (!Signals.stop) cond_wait(sleepCond, sleepLock);
- lock_release(sleepLock);
+ mutex.lock();
+ while (!Signals.stop) sleepCondition.wait(mutex);;
+ mutex.unlock();
}
void ThreadPool::init() {
- cond_init(sleepCond);
- lock_init(splitLock);
timer = new Thread(&Thread::timer_loop);
threads.push_back(new Thread(&Thread::main_loop));
read_uci_options();
delete threads[i];
delete timer;
- lock_destroy(splitLock);
- cond_destroy(sleepCond);
}
// Try to allocate available threads and ask them to start searching setting
// is_searching flag. This must be done under lock protection to avoid concurrent
// allocation of the same slave by another master.
- lock_grab(sp.lock);
- lock_grab(splitLock);
+ sp.mutex.lock();
+ mutex.lock();
for (size_t i = 0; i < size() && !Fake; ++i)
if (threads[i]->is_available_to(master))
master->splitPointsCnt++;
- lock_release(splitLock);
- lock_release(sp.lock);
+ mutex.unlock();
+ sp.mutex.unlock();
// Everything is set up. The master thread enters the idle loop, from which
// it will instantly launch a search, because its is_searching flag is set.
// We have returned from the idle loop, which means that all threads are
// finished. Note that setting is_searching and decreasing splitPointsCnt is
// done under lock protection to avoid a race with Thread::is_available_to().
- lock_grab(sp.lock); // To protect sp.nodes
- lock_grab(splitLock);
+ sp.mutex.lock(); // To protect sp.nodes
+ mutex.lock();
master->is_searching = true;
master->splitPointsCnt--;
pos.set_nodes_searched(pos.nodes_searched() + sp.nodes);
*bestMove = sp.bestMove;
- lock_release(splitLock);
- lock_release(sp.lock);
+ mutex.unlock();
+ sp.mutex.unlock();
return sp.bestValue;
}
void ThreadPool::set_timer(int msec) {
- lock_grab(timer->sleepLock);
+ timer->mutex.lock();
timer->maxPly = msec;
- cond_signal(timer->sleepCond); // Wake up and restart the timer
- lock_release(timer->sleepLock);
+ timer->sleepCondition.notify_one(); // Wake up and restart the timer
+ timer->mutex.unlock();
}
void ThreadPool::wait_for_search_finished() {
Thread* t = main_thread();
- lock_grab(t->sleepLock);
- cond_signal(t->sleepCond); // In case is waiting for stop or ponderhit
- while (!t->do_sleep) cond_wait(sleepCond, t->sleepLock);
- lock_release(t->sleepLock);
+ t->mutex.lock();
+ t->sleepCondition.notify_one(); // In case is waiting for stop or ponderhit
+ while (!t->do_sleep) sleepCondition.wait(t->mutex);
+ t->mutex.unlock();
}
const int MAX_THREADS = 32;
const int MAX_SPLITPOINTS_PER_THREAD = 8;
+struct Mutex {
+ Mutex() { lock_init(l); }
+ ~Mutex() { lock_destroy(l); }
+
+ void lock() { lock_grab(l); }
+ void unlock() { lock_release(l); }
+
+private:
+ friend struct ConditionVariable;
+
+ Lock l;
+};
+
+struct ConditionVariable {
+ ConditionVariable() { cond_init(c); }
+ ~ConditionVariable() { cond_destroy(c); }
+
+ void wait(Mutex& m) { cond_wait(c, m.l); }
+ void wait_for(Mutex& m, int ms) { timed_wait(c, m.l, ms); }
+ void notify_one() { cond_signal(c); }
+
+private:
+ WaitCondition c;
+};
+
class Thread;
struct SplitPoint {
SplitPoint* parent;
// Shared data
- Lock lock;
+ Mutex mutex;
volatile uint64_t slavesMask;
volatile int64_t nodes;
volatile Value alpha;
PawnTable pawnTable;
size_t idx;
int maxPly;
- Lock sleepLock;
- WaitCondition sleepCond;
+ Mutex mutex;
+ ConditionVariable sleepCondition;
NativeHandle handle;
Fn start_fn;
SplitPoint* volatile curSplitPoint;
public:
void init(); // No c'tor, Threads object is global and engine shall be fully initialized
- ~ThreadPool();
+ ~ThreadPool();
Thread& operator[](size_t id) { return *threads[id]; }
bool use_sleeping_threads() const { return useSleepingThreads; }
std::vector<Thread*> threads;
Thread* timer;
- Lock splitLock;
- WaitCondition sleepCond;
+ Mutex mutex;
+ ConditionVariable sleepCondition;
Depth minimumSplitDepth;
int maxThreadsPerSplitPoint;
bool useSleepingThreads;