Retire Thread::TERMINATED

Use proper way to detect for thread terimnation instead of
our homegrown flag.

It adds more code than it removes and adds also platform specific
code, neverthless I think is the way to go becuase Thread::TERMINATED
flag is intrinsecly racy given that when we raise it thread is still
_not_ terminated nor it can be, and also we don't want to reinvent
the (broken) wheel of thread termination detection when there is
already available the proper one.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>

diff --git a/src/search.cpp b/src/search.cpp
index eda9d2929847377916e20fc7608e3c7659531c2f..9992049efdacc4792138348d63febaed162bfc84 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -2168,7 +2168,6 @@ void Thread::idle_loop(SplitPoint* sp) {
           if (do_terminate)
           {
               assert(!sp);
-              state = Thread::TERMINATED;
               lock_release(&sleepLock);
               return;
           }

diff --git a/src/thread.cpp b/src/thread.cpp
index e631645b3a836350b32f6ed703509e662f6fa4af..a8e26b9f85c43a69a3f0260db1313285ca3ccee2 100644 (file)
--- a/src/thread.cpp
+++ b/src/thread.cpp
@@ -163,12 +163,12 @@ void ThreadsManager::init() {
       threads[i].threadID = i;
 
 #if defined(_MSC_VER)
-      bool ok = (CreateThread(NULL, 0, start_routine, (LPVOID)&threads[i].threadID , 0, NULL) != NULL);
+      threads[i].handle = CreateThread(NULL, 0, start_routine, (LPVOID)&threads[i].threadID, 0, NULL);
+      bool ok = (threads[i].handle != NULL);
 #else
-      pthread_t pthreadID;
-      bool ok = (pthread_create(&pthreadID, NULL, start_routine, (void*)&threads[i].threadID) == 0);
-      pthread_detach(pthreadID);
+      bool ok = (pthread_create(&threads[i].handle, NULL, start_routine, (void*)&threads[i].threadID) == 0);
 #endif
+
       if (!ok)
       {
           std::cout << "Failed to create thread number " << i << std::endl;
@@ -189,7 +189,14 @@ void ThreadsManager::exit() {
       {
           threads[i].do_terminate = true;
           threads[i].wake_up();
-          while (threads[i].state != Thread::TERMINATED) {}
+
+#if defined(_MSC_VER)
+          WaitForSingleObject(threads[i].handle, 0);
+          CloseHandle(threads[i].handle);
+#else
+          pthread_join(threads[i].handle, NULL);
+          pthread_detach(threads[i].handle);
+#endif
       }
 
       // Now we can safely destroy locks and wait conditions

diff --git a/src/thread.h b/src/thread.h
index aba43c902d6f0a455ef229fba02880b74832f92c..5325debe4c4c40e142e9a10318442e501a31a081 100644 (file)
--- a/src/thread.h
+++ b/src/thread.h
@@ -67,10 +67,9 @@ struct Thread {
 
   enum ThreadState
   {
-    SEARCHING,     // Thread is performing work
     AVAILABLE,     // Thread is waiting for work
     WORKISWAITING, // Master has ordered us to start searching
-    TERMINATED     // We are quitting and thread is terminated
+    SEARCHING      // Thread is performing work
   };
 
   void wake_up();
@@ -90,6 +89,12 @@ struct Thread {
   volatile int activeSplitPoints;
   volatile bool do_sleep;
   volatile bool do_terminate;
+
+#if defined(_MSC_VER)
+  HANDLE handle;
+#else
+  pthread_t handle;
+#endif
 };