namespace { extern "C" {
// start_routine() is the C function which is called when a new thread
- // is launched. It is a wrapper to member function pointed by start_fn.
+ // is launched. It is a wrapper to the virtual function idle_loop().
- long start_routine(Thread* th) { (th->*(th->start_fn))(); return 0; }
+ long start_routine(Thread* th) { th->idle_loop(); return 0; }
} }
// 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.
+// the the virtual function idle_loop(), going immediately to sleep.
-Thread::Thread(Fn fn) : splitPoints() {
+Thread::Thread() : 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()
-
if (!thread_create(handle, start_routine, this))
{
std::cerr << "Failed to create thread number " << idx << std::endl;
}
-// Thread d'tor waits for thread termination before to return.
+// Thread d'tor waits for thread termination before to return
Thread::~Thread() {
- assert(do_sleep);
-
do_exit = true; // Search must be already finished
- wake_up();
+ notify_one();
thread_join(handle); // Wait for thread termination
}
-// Thread::timer_loop() is where the timer thread waits maxPly milliseconds and
-// then calls check_time(). If maxPly is 0 thread sleeps until is woken up.
+// TimerThread::idle_loop() is where the timer thread waits msec milliseconds
+// and then calls check_time(). If msec is 0 thread sleeps until is woken up.
extern void check_time();
-void Thread::timer_loop() {
+void TimerThread::idle_loop() {
while (!do_exit)
{
mutex.lock();
- sleepCondition.wait_for(mutex, maxPly ? maxPly : INT_MAX);
+
+ if (!do_exit)
+ sleepCondition.wait_for(mutex, msec ? msec : INT_MAX);
+
mutex.unlock();
- check_time();
+
+ if (msec)
+ check_time();
}
}
-// Thread::main_loop() is where the main thread is parked waiting to be started
+// MainThread::idle_loop() is where the main thread is parked waiting to be started
// when there is a new search. Main thread will launch all the slave threads.
-void Thread::main_loop() {
+void MainThread::idle_loop() {
while (true)
{
mutex.lock();
- do_sleep = true; // Always return to sleep after a search
+ is_finished = true; // Always return to sleep after a search
is_searching = false;
- while (do_sleep && !do_exit)
+ while (is_finished && !do_exit)
{
Threads.sleepCondition.notify_one(); // Wake up UI thread if needed
sleepCondition.wait(mutex);
}
-// 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 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::init() {
- timer = new Thread(&Thread::timer_loop);
- threads.push_back(new Thread(&Thread::main_loop));
+ sleepWhileIdle = true;
+ timer = new TimerThread();
+ threads.push_back(new MainThread());
read_uci_options();
}
maxThreadsPerSplitPoint = Options["Max Threads per Split Point"];
minimumSplitDepth = Options["Min Split Depth"] * ONE_PLY;
- useSleepingThreads = Options["Use Sleeping Threads"];
size_t requested = Options["Threads"];
assert(requested > 0);
while (threads.size() < requested)
- threads.push_back(new Thread(&Thread::idle_loop));
+ threads.push_back(new Thread());
while (threads.size() > requested)
{
}
-// 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'.
sp.slavesMask |= 1ULL << i;
threads[i]->curSplitPoint = &sp;
threads[i]->is_searching = true; // Slave leaves idle_loop()
-
- if (useSleepingThreads)
- threads[i]->wake_up();
+ threads[i]->notify_one(); // Could be sleeping
if (++slavesCnt + 1 >= maxThreadsPerSplitPoint) // Master is always included
break;
// their work at this split point.
if (slavesCnt || Fake)
{
- master->idle_loop();
+ master->Thread::idle_loop(); // Force a call to base class 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.
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();
-}
-
-
// 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();
+ MainThread* 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);
+ while (!t->is_finished) sleepCondition.wait(t->mutex);
t->mutex.unlock();
}
Signals.stopOnPonderhit = Signals.firstRootMove = false;
Signals.stop = Signals.failedLowAtRoot = false;
- RootPosition = pos;
+ RootPos = pos;
Limits = limits;
SetupStates = states; // Ownership transfer here
RootMoves.clear();
if (searchMoves.empty() || count(searchMoves.begin(), searchMoves.end(), ml.move()))
RootMoves.push_back(RootMove(ml.move()));
- main_thread()->do_sleep = false;
- main_thread()->wake_up();
+ main_thread()->is_finished = false;
+ main_thread()->notify_one(); // Starts main thread
}
projects / stockfish / blobdiff