// and last thread are special. First one is the main search thread while the
// last one mimics a timer, they run in main_loop() and timer_loop().
-#if defined(_MSC_VER)
+#if defined(_WIN32) || defined(_WIN64)
DWORD WINAPI start_routine(LPVOID thread) {
#else
void* start_routine(void* thread) {
// Make a local copy to be sure doesn't become zero under our feet while
// testing next condition and so leading to an out of bound access.
- int localActiveSplitPoints = activeSplitPoints;
+ int sp_count = activeSplitPoints;
// 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.
- if ( !localActiveSplitPoints
- || splitPoints[localActiveSplitPoints - 1].is_slave[master])
+ if (!sp_count || (splitPoints[sp_count - 1].slavesMask & (1ULL << master)))
return true;
return false;
threads[i].do_sleep = (i != 0); // Avoid a race with start_thinking()
threads[i].threadID = i;
- bool ok = thread_create(threads[i].handle, start_routine, threads[i]);
-
- if (!ok)
+ if (!thread_create(threads[i].handle, start_routine, threads[i]))
{
std::cerr << "Failed to create thread number " << i << std::endl;
::exit(EXIT_FAILURE);
void ThreadsManager::exit() {
+ assert(threads[0].is_searching == false);
+
for (int i = 0; i <= MAX_THREADS; i++)
{
- threads[i].do_terminate = true; // Search must be already finished
+ threads[i].do_exit = true; // Search must be already finished
threads[i].wake_up();
thread_join(threads[i].handle); // Wait for thread termination
}
-// split_point_finished() checks if all the slave threads of a given split
-// point have finished searching.
-
-bool ThreadsManager::split_point_finished(SplitPoint* sp) const {
-
- for (int i = 0; i < activeThreads; i++)
- if (sp->is_slave[i])
- return false;
-
- return true;
-}
-
-
// 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
sp->parent = masterThread.splitPoint;
sp->master = master;
sp->is_betaCutoff = false;
+ sp->slavesMask = (1ULL << master);
sp->depth = depth;
sp->threatMove = threatMove;
sp->alpha = alpha;
sp->nodes = 0;
sp->ss = ss;
- for (i = 0; i < activeThreads; i++)
- sp->is_slave[i] = false;
-
// If we are here it means we are not available
assert(masterThread.is_searching);
// is_searching flag. This must be done under lock protection to avoid concurrent
// allocation of the same slave by another master.
lock_grab(threadsLock);
+ lock_grab(sp->lock); // To protect sp->slaves_mask
- for (i = 0; !Fake && i < activeThreads && workersCnt < maxThreadsPerSplitPoint; i++)
+ for (i = 0; !Fake && i < activeThreads; i++)
if (threads[i].is_available_to(master))
{
- workersCnt++;
- sp->is_slave[i] = true;
+ sp->slavesMask |= (1ULL << i);
threads[i].splitPoint = sp;
- // This makes the slave to exit from idle_loop()
+ // Allocate the slave and make it exit from idle_loop()
threads[i].is_searching = true;
if (useSleepingThreads)
threads[i].wake_up();
+
+ if (++workersCnt >= maxThreadsPerSplitPoint)
+ break;
}
+ lock_release(sp->lock);
lock_release(threadsLock);
// We failed to allocate even one slave, return
// finished. Note that changing state and decreasing activeSplitPoints is done
// under lock protection to avoid a race with Thread::is_available_to().
lock_grab(threadsLock);
+ lock_grab(sp->lock); // To protect sp->nodes
+
masterThread.is_searching = true;
masterThread.activeSplitPoints--;
-
- lock_release(threadsLock);
-
masterThread.splitPoint = sp->parent;
pos.set_nodes_searched(pos.nodes_searched() + sp->nodes);
+ lock_release(sp->lock);
+ lock_release(threadsLock);
+
return sp->bestValue;
}
void Thread::timer_loop() {
- while (!do_terminate)
+ while (!do_exit)
{
lock_grab(sleepLock);
timed_wait(sleepCond, sleepLock, maxPly ? maxPly : INT_MAX);
do_sleep = true; // Always return to sleep after a search
is_searching = false;
- while (do_sleep && !do_terminate)
+ while (do_sleep && !do_exit)
{
cond_signal(Threads.sleepCond); // Wake up UI thread if needed
cond_wait(sleepCond, sleepLock);
lock_release(sleepLock);
- if (do_terminate)
+ if (do_exit)
return;
Search::think();