X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fthread.cpp;h=7be8da88ab8b35efe7e7478a9892f6013268a396;hb=b8c5ea869ca80338f8b2fa6815fc92349b889750;hp=229c6beb365154b9c0ec8bc8eb5ebcc1f64c8ebe;hpb=62b32a47378fa84108bb8aee2192ba66c87c3280;p=stockfish
diff --git a/src/thread.cpp b/src/thread.cpp
index 229c6beb..7be8da88 100644
--- a/src/thread.cpp
+++ b/src/thread.cpp
@@ -17,6 +17,7 @@
along with this program. If not, see .
*/
+#include // For std::count
#include
#include
@@ -146,7 +147,7 @@ void Thread::wait_for(volatile const bool& b) {
bool Thread::cutoff_occurred() const {
- for (SplitPoint* sp = activeSplitPoint; sp; sp = sp->parent)
+ for (SplitPoint* sp = activeSplitPoint; sp; sp = sp->parentSplitPoint)
if (sp->cutoff)
return true;
@@ -176,10 +177,10 @@ bool Thread::is_available_to(Thread* master) const {
}
-// init() is called at startup. Initializes lock and condition variable and
-// launches requested threads sending them immediately to sleep. We cannot use
+// init() is called at startup to create and launch requested threads, that will
+// go immediately to sleep due to 'sleepWhileIdle' set to true. We cannot use
// 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.
+// engine at this point due to allocation of Endgames in Thread c'tor.
void ThreadPool::init() {
@@ -190,11 +191,11 @@ void ThreadPool::init() {
}
-// exit() cleanly terminates the threads before the program exits.
+// exit() cleanly terminates the threads before the program exits
void ThreadPool::exit() {
- delete timer; // As first becuase check_time() accesses threads data
+ delete timer; // As first because check_time() accesses threads data
for (size_t i = 0; i < threads.size(); i++)
delete threads[i];
@@ -240,12 +241,12 @@ bool ThreadPool::slave_available(Thread* master) const {
// 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
-// point objects), the function immediately returns. If splitting is possible, a
-// SplitPoint object is initialized with all the data that must be copied to the
-// helper threads and then helper threads are told that they have been assigned
-// work. This will cause them to instantly leave their idle loops and call
-// search(). When all threads have returned from search() then split() returns.
+// (because no idle threads are available), the function immediately returns.
+// If splitting is possible, a SplitPoint object is initialized with all the
+// data that must be copied to the helper threads and then helper threads are
+// told that they have been assigned work. This will cause them to instantly
+// leave their idle loops and call search(). When all threads have returned from
+// search() then split() returns.
template
Value ThreadPool::split(Position& pos, Stack* ss, Value alpha, Value beta,
@@ -253,23 +254,21 @@ Value ThreadPool::split(Position& pos, Stack* ss, Value alpha, Value beta,
int moveCount, MovePicker& mp, int nodeType) {
assert(pos.pos_is_ok());
+ assert(bestValue <= alpha && alpha < beta && beta <= VALUE_INFINITE);
assert(bestValue > -VALUE_INFINITE);
- assert(bestValue <= alpha);
- assert(alpha < beta);
- assert(beta <= VALUE_INFINITE);
- assert(depth > DEPTH_ZERO);
+ assert(depth >= Threads.minimumSplitDepth);
- Thread* master = pos.this_thread();
+ Thread* thisThread = pos.this_thread();
- if (master->splitPointsSize >= MAX_SPLITPOINTS_PER_THREAD)
- return bestValue;
+ assert(thisThread->searching);
+ assert(thisThread->splitPointsSize < MAX_SPLITPOINTS_PER_THREAD);
// Pick the next available split point from the split point stack
- SplitPoint& sp = master->splitPoints[master->splitPointsSize];
+ SplitPoint& sp = thisThread->splitPoints[thisThread->splitPointsSize];
- sp.master = master;
- sp.parent = master->activeSplitPoint;
- sp.slavesMask = 1ULL << master->idx;
+ sp.masterThread = thisThread;
+ sp.parentSplitPoint = thisThread->activeSplitPoint;
+ sp.slavesMask = 1ULL << thisThread->idx;
sp.depth = depth;
sp.bestMove = *bestMove;
sp.threatMove = threatMove;
@@ -277,38 +276,33 @@ Value ThreadPool::split(Position& pos, Stack* ss, Value alpha, Value beta,
sp.beta = beta;
sp.nodeType = nodeType;
sp.bestValue = bestValue;
- sp.mp = ∓
+ sp.movePicker = ∓
sp.moveCount = moveCount;
sp.pos = &pos;
sp.nodes = 0;
sp.cutoff = false;
sp.ss = ss;
- master->activeSplitPoint = &sp;
- int slavesCnt = 0;
-
- assert(master->searching);
-
// Try to allocate available threads and ask them to start searching setting
// 'searching' flag. This must be done under lock protection to avoid concurrent
// allocation of the same slave by another master.
mutex.lock();
sp.mutex.lock();
+ thisThread->splitPointsSize++;
+ thisThread->activeSplitPoint = &sp;
+
+ size_t slavesCnt = 1; // Master is always included
+
for (size_t i = 0; i < threads.size() && !Fake; ++i)
- if (threads[i]->is_available_to(master))
+ if (threads[i]->is_available_to(thisThread) && ++slavesCnt <= maxThreadsPerSplitPoint)
{
- sp.slavesMask |= 1ULL << i;
+ sp.slavesMask |= 1ULL << threads[i]->idx;
threads[i]->activeSplitPoint = &sp;
threads[i]->searching = true; // Slave leaves idle_loop()
threads[i]->notify_one(); // Could be sleeping
-
- if (++slavesCnt + 1 >= maxThreadsPerSplitPoint) // Include master
- break;
}
- master->splitPointsSize++;
-
sp.mutex.unlock();
mutex.unlock();
@@ -316,13 +310,13 @@ Value ThreadPool::split(Position& pos, Stack* ss, Value alpha, Value beta,
// it will instantly launch a search, because its 'searching' flag is set.
// The thread will return from the idle loop when all slaves have finished
// their work at this split point.
- if (slavesCnt || Fake)
+ if (slavesCnt > 1 || Fake)
{
- master->Thread::idle_loop(); // Force a call to base class idle_loop()
+ thisThread->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.
- assert(!master->searching);
+ assert(!thisThread->searching);
}
// We have returned from the idle loop, which means that all threads are
@@ -331,9 +325,9 @@ Value ThreadPool::split(Position& pos, Stack* ss, Value alpha, Value beta,
mutex.lock();
sp.mutex.lock();
- master->searching = true;
- master->splitPointsSize--;
- master->activeSplitPoint = sp.parent;
+ thisThread->searching = true;
+ thisThread->splitPointsSize--;
+ thisThread->activeSplitPoint = sp.parentSplitPoint;
pos.set_nodes_searched(pos.nodes_searched() + sp.nodes);
*bestMove = sp.bestMove;
@@ -359,8 +353,8 @@ void ThreadPool::wait_for_think_finished() {
}
-// start_thinking() wakes up the main thread sleeping in main_loop() so to start
-// a new search, then returns immediately.
+// start_thinking() wakes up the main thread sleeping in MainThread::idle_loop()
+// so to start a new search, then returns immediately.
void ThreadPool::start_thinking(const Position& pos, const LimitsType& limits,
const std::vector& searchMoves, StateStackPtr& states) {
@@ -377,7 +371,8 @@ void ThreadPool::start_thinking(const Position& pos, const LimitsType& limits,
RootMoves.clear();
for (MoveList ml(pos); !ml.end(); ++ml)
- if (searchMoves.empty() || count(searchMoves.begin(), searchMoves.end(), ml.move()))
+ if ( searchMoves.empty()
+ || std::count(searchMoves.begin(), searchMoves.end(), ml.move()))
RootMoves.push_back(RootMove(ml.move()));
main_thread()->thinking = true;