From 68d1bebd8e030d7ca84158d36bb352126f0a72ee Mon Sep 17 00:00:00 2001 From: jundery Date: Wed, 27 Feb 2013 17:55:56 -0700 Subject: [PATCH 1/1] Split() clean up locking Only unlock and relock when idle_loop() is actually called No functional change --- src/thread.cpp | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) diff --git a/src/thread.cpp b/src/thread.cpp index 51b25027..f5b8b5e2 100644 --- a/src/thread.cpp +++ b/src/thread.cpp @@ -303,28 +303,28 @@ void Thread::split(Position& pos, Stack* ss, Value alpha, Value beta, Value* bes slave->notify_one(); // Could be sleeping } - sp.mutex.unlock(); - Threads.mutex.unlock(); - // Everything is set up. The master thread enters the idle loop, from which // 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 > 1 || Fake) { + sp.mutex.unlock(); + Threads.mutex.unlock(); + 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(!searching); assert(!activePosition); - } - // We have returned from the idle loop, which means that all threads are - // finished. Note that setting 'searching' and decreasing splitPointsSize is - // done under lock protection to avoid a race with Thread::is_available_to(). - Threads.mutex.lock(); - sp.mutex.lock(); + // We have returned from the idle loop, which means that all threads are + // finished. Note that setting 'searching' and decreasing splitPointsSize is + // done under lock protection to avoid a race with Thread::is_available_to(). + Threads.mutex.lock(); + sp.mutex.lock(); + } searching = true; splitPointsSize--; -- 2.39.2