// Thread c'tor starts a newly-created thread of execution that will call
// the idle loop function pointed by start_fn going immediately to sleep.
-Thread::Thread(Fn fn) {
+Thread::Thread(Fn fn) : splitPoints() {
is_searching = do_exit = false;
maxPly = splitPointsCnt = 0;
curSplitPoint = NULL;
start_fn = fn;
idx = Threads.size();
-
- do_sleep = (fn != &Thread::main_loop); // Avoid a race with start_searching()
+ do_sleep = true;
if (!thread_create(handle, start_routine, this))
{
assert(do_sleep);
do_exit = true; // Search must be already finished
- wake_up();
+ notify_one();
thread_join(handle); // Wait for thread termination
}
}
-// Thread::wake_up() wakes up the thread, normally at the beginning of the search
-// or, if "sleeping threads" is used at split time.
+// Thread::notify_one() wakes up the thread, normally at the beginning of the
+// search or, if "sleeping threads" is used at split time.
-void Thread::wake_up() {
+void Thread::notify_one() {
mutex.lock();
sleepCondition.notify_one();
}
-// Thread::wait_for_stop_or_ponderhit() is called when the maximum depth is
-// reached while the program is pondering. The point is to work around a wrinkle
-// in the UCI protocol: When pondering, the engine is not allowed to give a
-// "bestmove" before the GUI sends it a "stop" or "ponderhit" command. We simply
-// wait here until one of these commands (that raise StopRequest) is sent and
-// then return, after which the bestmove and pondermove will be printed.
-
-void Thread::wait_for_stop_or_ponderhit() {
+// Thread::wait_for() set the thread to sleep until condition 'b' turns true
- Signals.stopOnPonderhit = true;
+void Thread::wait_for(volatile const bool& b) {
mutex.lock();
- while (!Signals.stop) sleepCondition.wait(mutex);;
+ while (!b) sleepCondition.wait(mutex);
mutex.unlock();
}
void ThreadPool::exit() {
+ delete timer; // As first becuase check_time() accesses threads data
+
for (size_t i = 0; i < threads.size(); i++)
delete threads[i];
-
- delete timer;
}
}
-// wake_up() is called before a new search to start the threads that are waiting
-// on the sleep condition and to reset maxPly. When useSleepingThreads is set
-// threads will be woken up at split time.
-
-void ThreadPool::wake_up() const {
-
- for (size_t i = 0; i < threads.size(); i++)
- {
- threads[i]->maxPly = 0;
- threads[i]->do_sleep = false;
-
- if (!useSleepingThreads)
- threads[i]->wake_up();
- }
-}
-
-
-// sleep() is called after the search finishes to ask all the threads but the
-// main one to go waiting on a sleep condition.
-
-void ThreadPool::sleep() const {
-
- // Main thread will go to sleep by itself to avoid a race with start_searching()
- for (size_t i = 1; i < threads.size(); i++)
- threads[i]->do_sleep = true;
-}
-
-
// available_slave_exists() tries to find an idle thread which is available as
// a slave for the thread 'master'.
}
+// set_timer() is used to set the timer to trigger after msec milliseconds.
+// If msec is 0 then timer is stopped.
+
+void ThreadPool::set_timer(int msec) {
+
+ timer->maxPly = msec;
+ timer->notify_one(); // Wake up and restart the timer
+}
+
+
// split() does the actual work of distributing the work at a node between
// several available threads. If it does not succeed in splitting the node
// (because no idle threads are available, or because we have no unused split
template <bool Fake>
Value ThreadPool::split(Position& pos, Stack* ss, Value alpha, Value beta,
- Value bestValue, Move* bestMove, Depth depth,
- Move threatMove, int moveCount, MovePicker* mp, int nodeType) {
+ Value bestValue, Move* bestMove, Depth depth, Move threatMove,
+ int moveCount, MovePicker& mp, int nodeType) {
assert(pos.pos_is_ok());
assert(bestValue > -VALUE_INFINITE);
sp.beta = beta;
sp.nodeType = nodeType;
sp.bestValue = bestValue;
- sp.mp = mp;
+ sp.mp = ∓
sp.moveCount = moveCount;
sp.pos = &pos;
sp.nodes = 0;
// 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.
- sp.mutex.lock();
mutex.lock();
+ sp.mutex.lock();
for (size_t i = 0; i < threads.size() && !Fake; ++i)
if (threads[i]->is_available_to(master))
threads[i]->is_searching = true; // Slave leaves idle_loop()
if (useSleepingThreads)
- threads[i]->wake_up();
+ threads[i]->notify_one();
if (++slavesCnt + 1 >= maxThreadsPerSplitPoint) // Master is always included
break;
master->splitPointsCnt++;
- mutex.unlock();
sp.mutex.unlock();
+ 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().
- sp.mutex.lock(); // To protect sp.nodes
mutex.lock();
+ sp.mutex.lock();
master->is_searching = true;
master->splitPointsCnt--;
pos.set_nodes_searched(pos.nodes_searched() + sp.nodes);
*bestMove = sp.bestMove;
- mutex.unlock();
sp.mutex.unlock();
+ mutex.unlock();
return sp.bestValue;
}
// Explicit template instantiations
-template Value ThreadPool::split<false>(Position&, Stack*, Value, Value, Value, Move*, Depth, Move, int, MovePicker*, int);
-template Value ThreadPool::split<true>(Position&, Stack*, Value, Value, Value, Move*, Depth, Move, int, MovePicker*, int);
-
-
-// set_timer() is used to set the timer to trigger after msec milliseconds.
-// If msec is 0 then timer is stopped.
-
-void ThreadPool::set_timer(int msec) {
-
- timer->mutex.lock();
- timer->maxPly = msec;
- timer->sleepCondition.notify_one(); // Wake up and restart the timer
- timer->mutex.unlock();
-}
+template Value ThreadPool::split<false>(Position&, Stack*, Value, Value, Value, Move*, Depth, Move, int, MovePicker&, int);
+template Value ThreadPool::split<true>(Position&, Stack*, Value, Value, Value, Move*, Depth, Move, int, MovePicker&, int);
// wait_for_search_finished() waits for main thread to go to sleep, this means
Thread* t = main_thread();
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 std::vector<Move>& searchMoves, StateStackPtr& states) {
wait_for_search_finished();
- SearchTime = Time::current_time(); // As early as possible
+ SearchTime = Time::now(); // As early as possible
Signals.stopOnPonderhit = Signals.firstRootMove = false;
Signals.stop = Signals.failedLowAtRoot = false;
- RootPosition = pos;
+ RootPos = pos;
Limits = limits;
SetupStates = states; // Ownership transfer here
RootMoves.clear();
RootMoves.push_back(RootMove(ml.move()));
main_thread()->do_sleep = false;
- main_thread()->wake_up();
+ main_thread()->notify_one();
}