8080879: Remove FlexibleWorkGang::set_for_termination

Reviewed-by: brutisso, kbarrett, pliden

hotspot/src/share/vm/gc/cms/concurrentMarkSweepGeneration.cpp

@@ -5258,18 +5258,14 @@ public:
                       CMSBitMap*       mark_bit_map,
                       AbstractWorkGang* workers,
                       OopTaskQueueSet* task_queues):
-    // XXX Should superclass AGTWOQ also know about AWG since it knows
-    // about the task_queues used by the AWG? Then it could initialize
-    // the terminator() object. See 6984287. The set_for_termination()
-    // below is a temporary band-aid for the regression in 6984287.
     AbstractGangTaskWOopQueues("Process referents by policy in parallel",
-      task_queues),
+      task_queues,
+      workers->active_workers()),
     _task(task),
     _collector(collector), _span(span), _mark_bit_map(mark_bit_map)
   {
     assert(_collector->_span.equals(_span) && !_span.is_empty(),
            "Inconsistency in _span");
-    set_for_termination(workers->active_workers());
   }
 
   OopTaskQueueSet* task_queues() { return queues(); }

hotspot/src/share/vm/gc/cms/parNewGeneration.cpp

@@ -576,12 +576,6 @@ ParNewGenTask::ParNewGenTask(ParNewGeneration* gen, Generation* old_gen,
     _strong_roots_scope(strong_roots_scope)
   {}
 
-// Reset the terminator for the given number of
-// active threads.
-void ParNewGenTask::set_for_termination(uint active_workers) {
-  _state_set->reset(active_workers, _gen->promotion_failed());
-}
-
 void ParNewGenTask::work(uint worker_id) {
   GenCollectedHeap* gch = GenCollectedHeap::heap();
   // Since this is being done in a separate thread, need new resource
@@ -757,9 +751,6 @@ public:
 
 private:
   virtual void work(uint worker_id);
-  virtual void set_for_termination(uint active_workers) {
-    _state_set.terminator()->reset_for_reuse(active_workers);
-  }
 private:
   ParNewGeneration&      _gen;
   ProcessTask&           _task;
@@ -949,6 +940,8 @@ void ParNewGeneration::collect(bool   full,
                                          *to(), *this, *_old_gen, *task_queues(),
                                          _overflow_stacks, desired_plab_sz(), _term);
 
+  thread_state_set.reset(n_workers, promotion_failed());
+
   {
     StrongRootsScope srs(n_workers);
 

hotspot/src/share/vm/gc/cms/parNewGeneration.hpp

@@ -250,10 +250,6 @@ public:
   HeapWord* young_old_boundary() { return _young_old_boundary; }
 
   void work(uint worker_id);
-
-  // Reset the terminator in ParScanThreadStateSet for
-  // "active_workers" threads.
-  virtual void set_for_termination(uint active_workers);
 };
 
 class KeepAliveClosure: public DefNewGeneration::KeepAliveClosure {

hotspot/src/share/vm/gc/cms/yieldingWorkgroup.hpp

@@ -147,6 +147,13 @@ public:
   bool completed() const { return _status == COMPLETED; }
   bool aborted()   const { return _status == ABORTED; }
   bool active()    const { return _status == ACTIVE; }
+
+  // This method configures the task for proper termination.
+  // Some tasks do not have any requirements on termination
+  // and may inherit this method that does nothing.  Some
+  // tasks do some coordination on termination and override
+  // this method to implement that coordination.
+  virtual void set_for_termination(uint active_workers) {}
 };
 // Class YieldingWorkGang: A subclass of WorkGang.
 // In particular, a YieldingWorkGang is made up of

hotspot/src/share/vm/gc/g1/g1CollectedHeap.cpp

@@ -4279,12 +4279,13 @@ protected:
   Mutex* stats_lock() { return &_stats_lock; }
 
 public:
-  G1ParTask(G1CollectedHeap* g1h, RefToScanQueueSet *task_queues, G1RootProcessor* root_processor)
+  G1ParTask(G1CollectedHeap* g1h, RefToScanQueueSet *task_queues, G1RootProcessor* root_processor, uint n_workers)
     : AbstractGangTask("G1 collection"),
       _g1h(g1h),
       _queues(task_queues),
       _root_processor(root_processor),
-      _terminator(0, _queues),
+      _terminator(n_workers, _queues),
+      _n_workers(n_workers),
       _stats_lock(Mutex::leaf, "parallel G1 stats lock", true)
   {}
 
@@ -4296,11 +4297,6 @@ public:
 
   ParallelTaskTerminator* terminator() { return &_terminator; }
 
-  virtual void set_for_termination(uint active_workers) {
-    terminator()->reset_for_reuse(active_workers);
-    _n_workers = active_workers;
-  }
-
   // Helps out with CLD processing.
   //
   // During InitialMark we need to:
@@ -5343,7 +5339,7 @@ void G1CollectedHeap::evacuate_collection_set(EvacuationInfo& evacuation_info) {
 
   {
     G1RootProcessor root_processor(this, n_workers);
-    G1ParTask g1_par_task(this, _task_queues, &root_processor);
+    G1ParTask g1_par_task(this, _task_queues, &root_processor, n_workers);
     // InitialMark needs claim bits to keep track of the marked-through CLDs.
     if (g1_policy()->during_initial_mark_pause()) {
       ClassLoaderDataGraph::clear_claimed_marks();

hotspot/src/share/vm/gc/shared/workgroup.cpp

@@ -133,8 +133,6 @@ void WorkGang::run_task(AbstractGangTask* task) {
 }
 
 void WorkGang::run_task(AbstractGangTask* task, uint no_of_parallel_workers) {
-  task->set_for_termination(no_of_parallel_workers);
-
   // This thread is executed by the VM thread which does not block
   // on ordinary MutexLocker's.
   MutexLockerEx ml(monitor(), Mutex::_no_safepoint_check_flag);

hotspot/src/share/vm/gc/shared/workgroup.hpp

@@ -59,13 +59,6 @@ public:
   // The argument tells you which member of the gang you are.
   virtual void work(uint worker_id) = 0;
 
-  // This method configures the task for proper termination.
-  // Some tasks do not have any requirements on termination
-  // and may inherit this method that does nothing.  Some
-  // tasks do some coordination on termination and override
-  // this method to implement that coordination.
-  virtual void set_for_termination(uint active_workers) {};
-
   // Debugging accessor for the name.
   const char* name() const PRODUCT_RETURN_(return NULL;);
   int counter() { return _counter; }
@@ -99,12 +92,9 @@ class AbstractGangTaskWOopQueues : public AbstractGangTask {
   OopTaskQueueSet*       _queues;
   ParallelTaskTerminator _terminator;
  public:
-  AbstractGangTaskWOopQueues(const char* name, OopTaskQueueSet* queues) :
-    AbstractGangTask(name), _queues(queues), _terminator(0, _queues) {}
+  AbstractGangTaskWOopQueues(const char* name, OopTaskQueueSet* queues, uint n_threads) :
+    AbstractGangTask(name), _queues(queues), _terminator(n_threads, _queues) {}
   ParallelTaskTerminator* terminator() { return &_terminator; }
-  virtual void set_for_termination(uint active_workers) {
-    terminator()->reset_for_reuse(active_workers);
-  }
   OopTaskQueueSet* queues() { return _queues; }
 };