X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fthread.h;h=b6809f4e37221dcca2329b62980f07a7e42c5238;hp=f8e65941f0d6beefa96a95aecc6195117978cca5;hb=a590d1d52deb22dfe42d5e59740ef07853320bb7;hpb=38112060dc2da351c6dde8f12d0ee5cfaeac5084 diff --git a/src/thread.h b/src/thread.h index f8e65941..b6809f4e 100644 --- a/src/thread.h +++ b/src/thread.h @@ -39,16 +39,20 @@ const size_t MAX_THREADS = 128; const size_t MAX_SPLITPOINTS_PER_THREAD = 8; const size_t MAX_SLAVES_PER_SPLITPOINT = 4; -/// Spinlock class wraps low level atomic operations to provide spin lock functionality + +/// Spinlock class wraps low level atomic operations to provide a spin lock class Spinlock { - std::atomic_flag lock; + std::atomic_int lock; public: - Spinlock() { std::atomic_flag_clear(&lock); } - void acquire() { while (lock.test_and_set(std::memory_order_acquire)) {} } - void release() { lock.clear(std::memory_order_release); } + Spinlock() { lock = 1; } // Init here to workaround a bug with MSVC 2013 + void acquire() { + while (lock.fetch_sub(1, std::memory_order_acquire) != 1) + while (lock.load(std::memory_order_relaxed) <= 0) {} + } + void release() { lock.store(1, std::memory_order_release); } }; @@ -110,7 +114,7 @@ struct Thread : public ThreadBase { Thread(); virtual void idle_loop(); bool cutoff_occurred() const; - bool available_to(const Thread* master) const; + bool can_join(const SplitPoint* sp) const; void split(Position& pos, Search::Stack* ss, Value alpha, Value beta, Value* bestValue, Move* bestMove, Depth depth, int moveCount, MovePicker* movePicker, int nodeType, bool cutNode); @@ -157,7 +161,7 @@ struct ThreadPool : public std::vector { MainThread* main() { return static_cast(at(0)); } void read_uci_options(); - Thread* available_slave(const Thread* master) const; + Thread* available_slave(const SplitPoint* sp) const; void wait_for_think_finished(); void start_thinking(const Position&, const Search::LimitsType&, Search::StateStackPtr&);