using namespace Search;
-ThreadsManager Threads; // Global object
+ThreadPool Threads; // Global object
namespace { extern "C" {
maxPly = splitPointsCnt = 0;
curSplitPoint = NULL;
start_fn = fn;
- threadID = Threads.size();
+ idx = Threads.size();
- do_sleep = (fn != &Thread::main_loop); // Avoid a race with start_thinking()
+ 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++)
+ for (size_t 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 " << threadID << std::endl;
+ std::cerr << "Failed to create thread number " << idx << std::endl;
::exit(EXIT_FAILURE);
}
}
Signals.stopOnPonderhit = true;
lock_grab(sleepLock);
-
- while (!Signals.stop)
- cond_wait(sleepCond, sleepLock);
-
+ while (!Signals.stop) cond_wait(sleepCond, sleepLock);
lock_release(sleepLock);
}
// Thread::is_available_to() checks whether the thread is available to help the
-// thread with threadID "master" at a split point. An obvious requirement is that
-// thread must be idle. With more than two threads, this is not sufficient: If
-// the thread is the master of some active split point, it is only available as a
-// slave to the threads which are busy searching the split point at the top of
-// "slave"'s split point stack (the "helpful master concept" in YBWC terminology).
+// thread 'master' at a split point. An obvious requirement is that thread must
+// be idle. With more than two threads, this is not sufficient: If the thread is
+// the master of some active split point, it is only available as a slave to the
+// slaves which are busy searching the split point at the top of slaves split
+// point stack (the "helpful master concept" in YBWC terminology).
-bool Thread::is_available_to(int master) const {
+bool Thread::is_available_to(Thread* master) const {
if (is_searching)
return false;
// No active split points means that the thread is available as a slave for any
// other thread otherwise apply the "helpful master" concept if possible.
- return !spCnt || (splitPoints[spCnt - 1].slavesMask & (1ULL << master));
+ return !spCnt || (splitPoints[spCnt - 1].slavesMask & (1ULL << master->idx));
}
// a c'tor becuase Threads is a static object and we need a fully initialized
// engine at this point due to allocation of endgames in Thread c'tor.
-void ThreadsManager::init() {
+void ThreadPool::init() {
cond_init(sleepCond);
lock_init(splitLock);
// d'tor cleanly terminates the threads when the program exits.
-ThreadsManager::~ThreadsManager() {
+ThreadPool::~ThreadPool() {
- for (int i = 0; i < size(); i++)
+ for (size_t i = 0; i < size(); i++)
delete threads[i];
delete timer;
// objects are dynamically allocated to avoid creating in advance all possible
// threads, with included pawns and material tables, if only few are used.
-void ThreadsManager::read_uci_options() {
+void ThreadPool::read_uci_options() {
maxThreadsPerSplitPoint = Options["Max Threads per Split Point"];
minimumSplitDepth = Options["Min Split Depth"] * ONE_PLY;
useSleepingThreads = Options["Use Sleeping Threads"];
- int requested = Options["Threads"];
+ size_t requested = Options["Threads"];
assert(requested > 0);
// on the sleep condition and to reset maxPly. When useSleepingThreads is set
// threads will be woken up at split time.
-void ThreadsManager::wake_up() const {
+void ThreadPool::wake_up() const {
- for (int i = 0; i < size(); i++)
+ for (size_t i = 0; i < size(); i++)
{
- threads[i]->do_sleep = false;
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 ThreadsManager::sleep() const {
+void ThreadPool::sleep() const {
- for (int i = 1; i < size(); i++) // Main thread will go to sleep by itself
- threads[i]->do_sleep = true; // to avoid a race with start_thinking()
+ for (size_t i = 1; i < size(); i++) // Main thread will go to sleep by itself
+ threads[i]->do_sleep = true; // to avoid a race with start_searching()
}
// available_slave_exists() tries to find an idle thread which is available as
-// a slave for the thread with threadID 'master'.
-
-bool ThreadsManager::available_slave_exists(int master) const {
+// a slave for the thread 'master'.
- assert(master >= 0 && master < size());
+bool ThreadPool::available_slave_exists(Thread* master) const {
- for (int i = 0; i < size(); i++)
+ for (size_t i = 0; i < size(); i++)
if (threads[i]->is_available_to(master))
return true;
// search(). When all threads have returned from search() then split() returns.
template <bool Fake>
-Value ThreadsManager::split(Position& pos, Stack* ss, Value alpha, Value beta,
- Value bestValue, Move* bestMove, Depth depth,
- Move threatMove, int moveCount, MovePicker* mp, int nodeType) {
+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) {
+
assert(pos.pos_is_ok());
assert(bestValue > -VALUE_INFINITE);
assert(bestValue <= alpha);
assert(beta <= VALUE_INFINITE);
assert(depth > DEPTH_ZERO);
- int master = pos.thread();
- Thread& masterThread = *threads[master];
+ Thread* master = pos.this_thread();
- if (masterThread.splitPointsCnt >= MAX_SPLITPOINTS_PER_THREAD)
+ if (master->splitPointsCnt >= MAX_SPLITPOINTS_PER_THREAD)
return bestValue;
// Pick the next available split point from the split point stack
- SplitPoint* sp = &masterThread.splitPoints[masterThread.splitPointsCnt++];
+ SplitPoint* sp = &master->splitPoints[master->splitPointsCnt];
- sp->parent = masterThread.curSplitPoint;
+ sp->parent = master->curSplitPoint;
sp->master = master;
sp->cutoff = false;
- sp->slavesMask = 1ULL << master;
+ sp->slavesMask = 1ULL << master->idx;
sp->depth = depth;
sp->bestMove = *bestMove;
sp->threatMove = threatMove;
sp->nodes = 0;
sp->ss = ss;
- assert(masterThread.is_searching);
+ assert(master->is_searching);
- masterThread.curSplitPoint = sp;
+ master->curSplitPoint = sp;
int slavesCnt = 0;
// Try to allocate available threads and ask them to start searching setting
lock_grab(sp->lock);
lock_grab(splitLock);
- for (int i = 0; i < size() && !Fake; ++i)
+ for (size_t i = 0; i < size() && !Fake; ++i)
if (threads[i]->is_available_to(master))
{
sp->slavesMask |= 1ULL << i;
break;
}
+ master->splitPointsCnt++;
+
lock_release(splitLock);
lock_release(sp->lock);
// 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 pass the split point as a parameter to the idle loop, which means that
- // the thread will return from the idle loop when all slaves have finished
+ // The thread will return from the idle loop when all slaves have finished
// their work at this split point.
if (slavesCnt || Fake)
{
- masterThread.idle_loop(sp);
+ master->idle_loop();
// In helpful master concept a master can help only a sub-tree of its split
// point, and because here is all finished is not possible master is booked.
- assert(!masterThread.is_searching);
+ assert(!master->is_searching);
}
// We have returned from the idle loop, which means that all threads are
lock_grab(sp->lock); // To protect sp->nodes
lock_grab(splitLock);
- masterThread.is_searching = true;
- masterThread.splitPointsCnt--;
- masterThread.curSplitPoint = sp->parent;
+ master->is_searching = true;
+ master->splitPointsCnt--;
+ master->curSplitPoint = sp->parent;
pos.set_nodes_searched(pos.nodes_searched() + sp->nodes);
*bestMove = sp->bestMove;
}
// Explicit template instantiations
-template Value ThreadsManager::split<false>(Position&, Stack*, Value, Value, Value, Move*, Depth, Move, int, MovePicker*, int);
-template Value ThreadsManager::split<true>(Position&, Stack*, Value, Value, Value, Move*, Depth, Move, int, MovePicker*, int);
+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);
-// ThreadsManager::set_timer() is used to set the timer to trigger after msec
-// milliseconds. If msec is 0 then timer is stopped.
+// set_timer() is used to set the timer to trigger after msec milliseconds.
+// If msec is 0 then timer is stopped.
-void ThreadsManager::set_timer(int msec) {
+void ThreadPool::set_timer(int msec) {
lock_grab(timer->sleepLock);
timer->maxPly = msec;
}
-// ThreadsManager::start_thinking() is used by UI thread to wake up the main
-// thread parked in main_loop() and starting a new search. If async is true
-// then function returns immediately, otherwise caller is blocked waiting for
-// the search to finish.
+// wait_for_search_finished() waits for main thread to go to sleep, this means
+// search is finished. Then returns.
+
+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);
+}
+
-void ThreadsManager::start_thinking(const Position& pos, const LimitsType& limits,
- const std::set<Move>& searchMoves, bool async) {
- Thread& main = *threads.front();
+// start_searching() wakes up the main thread sleeping in main_loop() so to start
+// a new search, then returns immediately.
- lock_grab(main.sleepLock);
+void ThreadPool::start_searching(const Position& pos, const LimitsType& limits,
+ const std::vector<Move>& searchMoves) {
+ wait_for_search_finished();
- while (!main.do_sleep)
- cond_wait(sleepCond, main.sleepLock); // Wait main thread has finished
+ SearchTime.restart(); // As early as possible
Signals.stopOnPonderhit = Signals.firstRootMove = false;
Signals.stop = Signals.failedLowAtRoot = false;
- RootPosition.copy(pos, 0);
+ RootPosition = pos;
Limits = limits;
RootMoves.clear();
- for (MoveList<MV_LEGAL> ml(pos); !ml.end(); ++ml)
- if (searchMoves.empty() || searchMoves.count(ml.move()))
+ for (MoveList<LEGAL> ml(pos); !ml.end(); ++ml)
+ if (searchMoves.empty() || count(searchMoves.begin(), searchMoves.end(), ml.move()))
RootMoves.push_back(RootMove(ml.move()));
- main.do_sleep = false;
- cond_signal(main.sleepCond); // Wake up main thread and start searching
-
- if (!async)
- while (!main.do_sleep)
- cond_wait(sleepCond, main.sleepLock);
-
- lock_release(main.sleepLock);
-}
-
-
-// ThreadsManager::stop_thinking() is used by UI thread to raise a stop request
-// and to wait for the main thread finishing the search. We cannot return before
-// main has finished to avoid a crash in case of a 'quit' command.
-
-void ThreadsManager::stop_thinking() {
-
- Thread& main = *threads.front();
-
- Search::Signals.stop = true;
-
- lock_grab(main.sleepLock);
-
- cond_signal(main.sleepCond); // In case is waiting for stop or ponderhit
-
- while (!main.do_sleep)
- cond_wait(sleepCond, main.sleepLock);
-
- lock_release(main.sleepLock);
+ main_thread()->do_sleep = false;
+ main_thread()->wake_up();
}